Directory of Researchers

DAN Tomohisa
Graduate School of Maritime Sciences / Department of Maritime Sciences
Professor
Mechanical Engineering
Last Updated :2024/03/16

Researcher Profile and Settings

Affiliation

  • <Faculty / Graduate School / Others>

    Graduate School of Maritime Sciences / Department of Maritime Sciences
  • <Related Faculty / Graduate School / Others>

    Faculty of Oceanology / Department of Oceanology, Faculty of Maritime Sciences / Department of Marine Engineering

Teaching

Research Activities

Research Interests

  • KH-RT(waves) Breakup Model
  • Organized Structure in Spray
  • Taylor Analogy Breakup Model
  • Discrete Droplet Model
  • Plasma
  • mutagenicity
  • Environment Protection
  • Diesel Engine
  • Fuel
  • Alternative Fuel
  • Fuel of Next Generation
  • Environmental Measures
  • Atomization
  • Exhaust Emission
  • Marine Engineering
  • Ship Engine
  • Maritime Education and Trainning
  • Marine Engine Plant Simulator
  • Engine Room Simulator
  • Internal Comubustion Engine

Research Areas

  • Aerospace, marine, and maritime Engineering / Marine and maritime engineering
  • Manufacturing technology (mechanical, electrical/electronic, chemical engineering) / Thermal engineering

Committee Memberships

  • May 2022 - Present, The Japan Institute of Marine Engineering, Boarding Member (International Affairs)
  • May 2019 - Present, 公益社団法人日本マリンエンジニアリング学会, JIME10年ビジョン実行委員会;委員
  • Oct. 2018 - Present, PAAMES (Pan Asian Association of Maritime Engineering Societies) 9th PAAMES/AMEC2020 (St.Petersburg), International Standing Committee & International Program Committee ; Member
  • May 2018 - Present, 公益社団法人日本マリンエンジニアリング学会, 国際交流委員会 ; 委員長
  • Apr. 2018 - Present, Japan Society of Mechanical Engineers (JSME), Engine System Division, Committee for Internal Combustion Engines Symposium ; Secretary
  • May 2017 - Present, The Japan Institute of Marine Engineering, Director (Exectutive Director)
  • May 2017 - Present, 公益社団法人日本マリンエンジニアリング学会, 理事(業務執行理事)
  • May 2014 - Present, The Japan Institute of Marine Engineering, Research Committee for Diesel Engines (First Category) ; Chairperson
  • May 2014 - Present, 公益社団法人日本マリンエンジニアリング学会, ディーゼル機関研究委員会(第1種研究委員会) ; 委員長
  • May 2018 - Apr. 2020, The Japan Institute of Marine Engineering (JIME), International Exchange Committee ; Chair
  • May 2018 - Apr. 2019, The Japan Institute of Marine Engineering (JIME), Comittee for Formulatoin of JIME 10 Years' Plan ; Member
  • May 2018 - Apr. 2019, 公益社団法人日本マリンエンジニアリング学会, JIME 10年ビジョン策定委員会 ; 委員
  • Apr. 2018 - Nov. 2018, 一般社団法人日本機械学会, エンジンシステム部門 内燃機関シンポジウム委員会 ; 幹事
  • Nov. 2016 - Oct. 2018, PAAMES (Pan Asian Association of Maritime Engineering Societies), 8th PAAMES/AMEC208 (Busan), International Standing Committee & International Program Comittee ; Member
  • Nov. 2016 - Oct. 2018, PAAMES (Pan Asian Association of Maritime Engineering Societies), 8th PAAMES/AMEC2018 (Busan), International Standing Committee & International Program Committee ; Member
  • May 2016 - Apr. 2018, The Japan Institute of Marine Engineering, Committee for Engineers' Education ; Chairperson
  • May 2016 - Apr. 2018, 公益社団法人日本マリンエンジニアリング学会, 技術者教育委員会 ; 委員長
  • May 2003 - Apr. 2018, Japan Institute of Marine Engineering, Committee for International Affairs ; Member
  • May 2003 - Apr. 2018, 日本マリンエンジニアリング学会, 国際交流委員会 ; 委員
  • Apr. 2013 - Mar. 2018, Japan Society of Mechanical Engineers, Kansai Branch, Executive Committee of MECHAVOCATION ; Member
  • Apr. 2013 - Mar. 2018, 一般社団法人日本機械学会 関西支部, メカボケーション実行委員会 ; 委員
  • Aug. 2017 - Dec. 2017, The Korean Society of Marine Engineering, Organizing Committee of ISMT2017 ; International Adivisory Committee
  • Aug. 2017 - Dec. 2017, The Korean Society of Marine Engineering, Organizing Committee of ISMT2017 ; International Adivisory Committee
  • Aug. 2017 - Dec. 2017, The Japan Institute of Marine Engineering, Member Enhancement Committee ; Member
  • Aug. 2017 - Dec. 2017, 公益社団法人日本マリンエンジニアリング学会, 会員増強対策委員会 ; 委員
  • Apr. 2015 - Dec. 2017, The Japan Institute of Marine Engineering, ISME2017 (11th International Symposium on Marine Engineering) TOKYO, Local Executive Committee ; Chairperson of Technical Committee
  • Apr. 2015 - Dec. 2017, The Japan Institute of Marine Engineering, ISME (International Symposium on Marine Engineering) 2017(Tokyo), Local Executive Committee ; Chair of Technical Committee
  • May 2015 - Apr. 2017, The Japan Institute of Marine Engineering, Delegate & Director
  • May 2015 - Apr. 2017, 公益社団法人日本マリンエンジニアリング学会, 代議員・理事
  • Dec. 2014 - Nov. 2016, PAAMES (Pan Asian Association of Maritime Engineering Societies), 7th PAAMES/AMEC2016 (Hong Kong), International Standing Comittee & International Program Committee ; Member
  • Oct. 2014 - Oct. 2016, PAAMES (Pan Asian Association of Maritime Engineering Societies), 7th PAAMES/AMEC2016 (Hong Kong), International Standing Committee & International Program Committee ; Member
  • May 2015 - Apr. 2016, 公益社団法人 日本マリンエンジニアリング学会, 技術者教育委員会 ; 副委員長
  • Apr. 2015 - Mar. 2016, Japan Institute of Marine Engineering, Committee for Engineers' Education ; Vice-chair
  • Jan. 2007 - Dec. 2014, Japan Institute of Marine Engineering, ISME (International Symposium on Marine Engineering) 2009(Busan), 2011(Kobe), 2014(Harbin), International Standing Committee ; Member
  • Dec. 2012 - Oct. 2014, PAAMES (Pan Asian Association of Maritime Engineering Societies), 6th PAAMES/AMEC2014 (Hangzhou), International Standing Comittee & International Program Comittee ; Member
  • Dec. 2012 - Oct. 2014, PAAMES (Pan Asian Association of Maritime Engineering Societies), 6th PAAMES/AMEC2014 (Hangzhou), International Standing Committee & International Program Committee ; Member
  • Jan. 2007 - Sep. 2014, Japan Institute of Marine Engineering, ISME (International Symposium on Marine Engineering) 2009(Busan), 2011(Kobe), 2014(Harbin), International Standing Committee ; Member
  • Apr. 2005 - Mar. 2014, Japan Institute of Marine Engineering, Research Committee for Diesel Engines (First Category) ; Secretary
  • Apr. 2005 - Mar. 2014, 日本マリンエンジニアリング学会, ディーゼル機関研究委員会(第1種研究委員会) ; 幹事
  • Dec. 2010 - Dec. 2012, PAAMES (Pan Asian Association of Maritime Engineerign Societies), 5th PAAMES/AMEC2012 (Taipei), International Standing Comittee & International Program Comittee ; Member
  • Dec. 2010 - Dec. 2012, PAAMES (Pan Asian Association of Maritime Engineerign Societies), 5th PAAMES/AMEC2012 (Taipei), International Standing Committee & International Program Committee ; Member
  • Apr. 2009 - Mar. 2011, Japan Society of Mechanical Engineers, Editorial Committee ; Member
  • Apr. 2009 - Mar. 2011, Japan Society of Mechanical Engineers, Engine System Division ; Delegate
  • Apr. 2009 - Mar. 2011, 日本機械学会, 編集委員会 ; 委員
  • Apr. 2009 - Mar. 2011, 日本機械学会, エンジンシステム部門 ; 代議員
  • Apr. 2005 - Mar. 2010, Japan Institute of Marine Engineering, Research Committee for Numerical Simulation (Second Category) ; Secretary
  • Apr. 2005 - Mar. 2010, 日本マリンエンジニアリング学会, 数値シミュレーション研究委員会(第2種研究委員会) ; 幹事
  • Oct. 2006 - Oct. 2008, PAAMES (Pan Asian Association of Maritime Engineering Societies), 3rd PAAMES/AMEC2008 (Chiba), Loacal Executive Committtee & International Standing Committee ; Member
  • Oct. 2006 - Oct. 2008, PAAMES (Pan Asian Association of Maritime Engineering Societies), 3rd PAAMES/AMEC2008 (Chiba), Loacal Executive Committtee & International Standing Committee ; Member
  • Apr. 2005 - Oct. 2006, PAAMES (Pan Asian Association of Maritime Engineering Societies), 2nd PAAMES/AMEC2006 (Cheju), Technical Program Committee ; Member
  • Apr. 2005 - Oct. 2006, PAAMES (Pan Asian Association of Maritime Engineering Societies), 2nd PAAMES/AMEC2006 (Cheju), Technical Program Committee ; Member
  • Apr. 2001 - Mar. 2002, Japan Institute of Marine Engineering, Delegation of YME (Young Marine Enginners) ; Leader of Group YME2001
  • Apr. 2001 - Mar. 2002, 日本マリンエンジニアリング学会, YME (Young Marine Enginners)使節員 ; 使節員リーダー

Awards

  • Sep. 2021 Japan Institute of Marine Engineering, Best Presentation Awards, Clarification of phenomena around electrodes for plasma-assisted combustion

    Kaoru Yamana

  • May 2020 The Japane Institute of Marine Engineering, Senior Marine Engineer (CPD)

  • Nov. 2018 Asia Maritime & Fisheries Universities Forum, AMFUF 2018 Paper Awards (KINPR Chairman Prize), Crude Plant Oil as Fuel of Internal Combustion Engines for Green Shipping

    DAN Tomohisa

  • May 2018 The Japane Institue of Marine Engineering, Award for Distinguished Service, Contribution to International Symposium ISME2017

    Tomohisa Dan

  • May 2017 The Japan Institute of Marine Engineering, Distinguished Service Award, CPD Contributions

    Tomohisa Dan

    Others

  • Nov. 2015 Kobe Machinery and Metal Firms Association Inc., Kobe Machinery and Metal Firms Association Inc. Award, Combustion Analysis of Straight Jatropha Oil for Application to Diesel Engine

    Takahiro Nakamoto, Supervised, by Tomohisa Da

    Japan society

  • May 2013 The Japan Institute of Marine Engineering, Lloyd's Register Manson Prize, Measurement of Bunker Oil / DME Blended Fuel Viscosity for Diesel Engine Application

    DAN Tomohisa, RYU Younghyun, ASANO Ichiro

  • May 2010 The Japan Society of Naval Architects and Ocean Engineers, Kansai Branch, Excellence Award (Joint Student's Presentation Meeting), Combustion Anaysis of DME Blended Fuel in Diesel Engine

    Ryota Ouchi, Supervisor Tomohisa Da

    Japan society

Published Papers

  • Improvement of Fuel Combustion by Discharge Plasma Assist. -Adaptation to Diesel and DF Engines

    Kakeru Okita, Tomohisa Dan, Ichiro Asano, Kaoru Yamana, Kenzaburo Tsuzuki, Shun Anno, Aisa Nakahara, Hiroshi Akamatsu, Takamitsu Yoshimoto, Morohiro Ohshima

    Corresponding, Oct. 2023, 10th PAAMES & AMEC2023, English

    International conference proceedings

  • Study of mixing fuels by continuous stirring device

    Daiki Itho, Tomohisa Dan, Ichiro Asano, Yu Mihara, Hiroshi Takahashi, Keisuke Ono, Kazushi Suzuki

    Corresponding, Sep. 2023, 93rd (Reiwa 5) Marine Engineering Conference, Japanese

    Research society

  • Study on estimation of changes in exhaust gas due to corona discharge

    Shun Anno, Ayaka Hirai, Tomohisa Dan, Ichiro Asano

    Corresponding, Aug. 2023, Review of Graduate School of Maritime Sciences, Kobe University, 20, 1 - 6, Japanese

    Research institution

  • Simultaneous reduction of CO2, NOx, and BC by using water-mixed bio-fuels from vegetable and animal

    Yamanishi Dai, Tsuda Minoru, Maeda Kazuyuki, Dan Tomohisa

    Oct. 2022, Proceedings of 92nd Marine Engineering Conference, OS2-4, 145 - 146, Japanese

    Symposium

  • Fundamental characteristic of new two fluid mixing system available to continuous operation under pressurized condition

    Mihara Yu, Suzuki Kazushi, Ono Keisuke, Daiki Ono, Asano Ichiro, Dan Tomohisa

    Oct. 2022, Proceedings of 92nd Marine Engineering Conference, OS2-3, 143 - 144, Japanese

    Symposium

  • Study on Application of Plasma-Assisted Combustion in Diesel Engines

    Anno Shun, Dan Tomohisa, Asano Ichiro, Yamana Kaoru, Tuszuki Kenzaburo, Okita Kakeru, Takehara Hiryu

    Corresponding, Oct. 2022, Proceedings of 92nd Marine Engineering Conference, OS2-2, 141 - 142, Japanese

    Symposium

  • Study of water plant oil emulsion fuel by using SPG membrane

    Kosei NAGAI, Aketora YASUNAMI, Ichiro ASANO, Tomohisa DAN

    日本液体微粒化学会, 17 Dec. 2021, Proceedings of Thirtieth ILASS-Japan Symposium, (A212), 1 - 5, Japanese

  • Measures for Environmental Regulations of Marine 4-stroke Engines

    Tomohisa Dan

    28 Sep. 2021, Proceedings of 91st (Reiwa 3) Marine Engineering Conference, (S2-4), 59 - 64, Japanese

    [Invited]

    Research society

  • Trial study to form plasma-assisted combustion inside engine cylinder

    Kezaburo Tuszuki, Kaoru Yamana, Shun Anno, ichiro Asano, Tomohisa Dan, Hiroshi Akamatsu, Motohiro Ohsima, Takamitsu Yoshimoto

    27 Sep. 2021, Proceedings of 91st (Reiwa 3) Marine Engineering Conference, 91st (309), 245 - 246, Japanese

    Research society

  • Clarification of phenomena around electrodes for plasma-assisted combustion

    Kaoru Yamana, Kezaburo Tuszuki, Shun Anno, ichiro Asano, Tomohisa Dan, Hiroshi Akamatsu, Motohiro Ohsima, Takamitsu Yoshimoto

    27 Sep. 2021, Proceedings of 91st (Reiwa 3) Marine Engineering Conference, 91st (308), 243 - 244, Japanese

    Research society

  • Fuel combustion improvement by emitted plasma assistance -Trial with electrode configuration and their effects

    Kenzaburo Tsuzuki, Kaoru Yamana, Shun Anno, Ichiro Asano, Hiroshi Akamatsu, Takamitsu Yoshimoto, Tomohisa Dan

    21 Sep. 2021, International Conference on PAAMES/AMEC 2021, 1 - 7, English

    International conference proceedings

  • Application of plasma assistance for internal combustion Engine -Discharge phenomenon under high pressure ambient conditions

    Kaoru Yamana, Kenzaburo Tsuzuki, Shun Anno, Ichiro Asano, Hiroshi Akamatsu, Takamitsu Yoshimoto, Tomohisa Dan

    21 Sep. 2021, International Conference on PAAMES/AMEC2021, 1 - 7, English

    International conference proceedings

  • Study on the application of alcohol-based fuels in spark-ignited outboard engines

    Tokushi Ito, Kodai Nakano, Wataru Miyazaki, Tomohisa Dan, Ichiro Asano, Hideo Okamura

    Aug. 2021, Review of Graduate School of Maritime Sciences, Kobe University, 18, 41 - 49, Japanese

    Research institution

  • Yu Mihara, Ichiro Asano, Tomohisa Dan, Hideo Okamura, Chisato Matsumura, Yuki Haga, Ryouhei Nakatsubo

    The Japan Institute of Marine Engineering, 01 May 2021, Marine Engineering, 56 (3), 473 - 483, Japanese

    [Refereed]

    Scientific journal

  • Yu MIHARA, Daiki KURO-OKA, Tomoki SHIRAHAMA, Kenta KUWAOKA, Takashi SUZUKI, Ichiro ASANO, Tomohisa DAN

    SAE International, 19 Dec. 2019, SAE Technical Paper Series, English

    [Refereed]

    Scientific journal

  • Relations between mutagenicity and polycyclic aromatic hydrocarbons of the soot from diesel engine

    Kento Hayami, Akira Yoshida, Masashi Kusu, Go-ichi Kon, Hideo Okamura, Tomohisa Dan, Yoshinori Haga, Ryohei Nakatsubo, Senri Matsumura

    The Japan Institute of Marine Engineering, Oct. 2019, Proceedings of 89th Marine Engineering Conference, Japanese

    Symposium

  • Satoshi Asaoka, Tomohisa Dan, Ichiro Asano, Shinjiro Hayakawa, Kazuhiko Takeda

    © 2019 Elsevier Ltd Ship fuels are highly associated with the emission of particulate matter and sulfur. Sulfur adsorbed on particulate matter in exhaust gases from fuels is generally considered to be sulfate. However, other chemical species of sulfur adsorbed on particulate matter in ship exhaust gases are not well known. The purpose of this study is to identify sulfur species adsorbed on particulate matter in ship exhaust gases using X-ray absorption fine structure. Particulate matter and soot samples were collected from a container carrier, a tugboat, an electric propulsion vessel, training vessels, and a marine engine, and sulfur species of particulate matter and soot were identified by X-ray absorption fine structure analysis. Sulfur emission adsorbed on particulate matter and sulfur species did not change between high and middle loads. In this study, sulfonate derived from fuel or oxidation of sulfide in fuel was identified in addition to sulfate. Total sulfur and sulfate concentrations in soot increased with increasing fuel sulfur content. The concentration of organosulfurorganosulfurs in soot such as thiophen and sulfonate, which originated mainly from fuel and engine oil, tended to increase with increasing fuel sulfur content.

    May 2019, Chemosphere, 223, 399 - 405, English

    [Refereed]

    Scientific journal

  • Dan Tomohisa

    The Japan Institute of Marine Engineering, 2019, Marine Engineering, 54 (3), 350 - 357, Japanese

    Scientific journal

  • Crude Plant Oil as Fuel of Internal Combustion Engines for Green Shipping (tentative)

    Tomohisa Dan

    Nov. 2018, The 17th Annual Conference, The Asia Maritime & Fisheries Universities Forum (AMFUF 2018), (Guangdong Ocean Univ., China), 159 - 172, English

    International conference proceedings

  • Research of In-Line Mixing of Dimethyl ether / Bunker oil Blend for Diesel Engine

    Yu Mihara, Takashi Suzuki, Ichiro Asano, Tomohisa Dan

    Abstract reviewed with full-length paper

    Oct. 2018, 8th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2018 (Busan), 319 - 326, English

    [Refereed]

    International conference proceedings

  • Engine Characteristic due to Cold Start of Diesel Engine

    Takuya Nakaguchi, Takashi Miwa, Ichiro Asano, Tomohisa Dan

    Abstract reviewed with full-length paper

    Oct. 2018, 8th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2018 (Busan), 312 - 318, English

    [Refereed]

    International conference proceedings

  • Evaluation of Bio-Gasoline Combustion in Outboard Spark Ignition Engine

    Wataru Miyazaki, Toru Hayakawa, Kodai Nakano, Ichiro Asano, Hideo Okamura, Tomohisa Dan

    Abstract reviewed with full-length paper

    Oct. 2018, 8th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2018 (Busan), 597 - 601, English

    [Refereed]

    International conference proceedings

  • Analysis of Organic Contamination in Ship Engine Soot

    Senri Matsumura, Yoshinori Haga, Ryosuke Yoshiori, Ryohei Nakatsubo, Go-ichi Kon, Hideo Okamura, Tomohisa Dan, Toshiki Tojo, Hitomi Hasegawa, Takashi Miyawaki, Takahiro Nishino, Takeshi Nakano

    Japan Society on Water Environment, Sep. 2018, Proceedings of 21st Symposium of JSWE (Shimane), 21st, pp.157, Japanese

    Symposium

  • Dai Yamanishi, Kazuyuki Maeda, Tomohisa Dan

    Re-print of ISME2017 Tokyo

    May 2018, Journal of the Japan Institute of Marine Engineering, 53 (3), 380 - 385, English

    [Refereed]

    Scientific journal

  • Crude Plant Oil Combustion in Diesel Engine with Blending Gas Oil and Liquefied Dimethyl Ether

    Tomohisa Dan, Kiminobu Yoshimura, Shingo Nishiyama, Ichiro Asano

    Oct. 2017, International Symposium on Marine Engineering and Technology 2017 (ISMT2017), 17 - 19, English

    [Refereed]

    International conference proceedings

  • Conceptual Proposal of Advanced Sensory Marine Engine Room Simulator

    Hiromasa Ikawa, Takashi Miwa, Tomohisa Dan, Yoshiharu Itami

    Oct. 2017, International Symposium on Marine Engineering and Technology 2017 (ISMT2017), 47 - 49, English

    [Refereed]

    International conference proceedings

  • Combustion Analysis of Dimethyl ether / Bunker oil Blend Supplied on In-Line Mixing in IDI Diesel Engine (2nd Report: Evaluation of Optimum Fuel Circulation for Experimental In-Line Mixing System)

    Yu Mihara, Takashi Suzuki, Ichiro Asano, Tomohisa Dan

    Oct. 2017, International Symposium on Marine Engineering and Technology 2017 (ISMT2017), 41 - 42, English

    [Refereed]

    International conference proceedings

  • Applying Plasma Assisted Combustion for Internal Combustion Engine

    Kenya Hirosawa, Takamitsu Yoshimoto, Hiroshi Akamatsu, Ichiro Asano, Tomohisa Dan

    Oct. 2017, International Symposium on Marine Engineering and Technology 2017 (ISMT2017), 38 - 40, English

    [Refereed]

    International conference proceedings

  • Application of a newly developed Water Mixture Fuel generator to IMO regulations

    Dai Yamanishi, Kazuyuki Maeda, Tomohisa Dan

    Oct. 2017, The 11th International Symposium on Marine Engineering (ISME2017 TOKYO), (B10-304), 359 - 364, English

    [Refereed]

    International conference proceedings

  • Evaluation of Bio-gasoline Combustion in Outboard Spark Ignition Engine

    Toru Hayakawa, Wataru Miyazaki, Hideo Okamura, Ichiro Asano, Tomohisa Dan

    Oct. 2017, The 11th International Symposium on Marine Engineering (ISME2017 TOKYO), (A03-208), 213 - 217, English

    [Refereed]

    International conference proceedings

  • Change in Combustion State of Plant Oil by Mixing Liquefied Dimethyl Ether and Gas Oil with Direct Injection Diesel Engine

    Tomohisa Dan, Kiminobu Yoshimura, Shingo Nishiyama, Ichiro Asano

    Oct. 2017, The 11th International Symposium on Marine Engineering (ISME2017 TOKYO), (AS1-103), 48 - 51, English

    [Invited]

    International conference proceedings

  • A Basic Research on Engine Room Simulator Training Corresponding to Recent Trend in Marine Engines

    Keiji Sato, Tomohisa Dan

    It is required for shipping company to operate vessels as safe as possible with saving energy for operations. Such operations will bring less emission of harmful matters from vessels which results in both ecological and economical friendly. Marine engine manufacturers have been actively engaged in developing engines with less emission of air pollutants such as NOx and SOx. For further reduction in PM and CO2, an engine which uses natural gas as main fuel has been developed. Moreover, an electronically controlled system has been applied to engines, such as in fuel injection or in valve operations, in order to control fuel combustion precisely in wide range of engine load condition. Despite of such progress in ship engine technology and operations, it should be said that those aspects do not sufficiently reflect to courses in maritime education and training field. Therefore, this study is motivated to correlate the marine engine trends to maritime education and training, especially in training with marine engineering simulators. And it is aimed to establish basic content and procedure in the simulator-education that make marine engineers to aware of reduction in harmful exhaust gases and fuel consumption. This article consists of following three parts in order to figure out the study objectives. First of all, we investigated recent tasks that marine engineers were required in ship operations, as well as current trends of simulator-education. As the next, we carried out experimental measurement of NOx emission from main engine of the training ship “Kaigi Maru”. It is supposed that such emission trends will be useful if they are correlated to training with simulators. And as final, the measured results of NOx emission were compared and discussed with proposed NOx formula.

    海技教育機構, Mar. 2017, Review of the Japan agency of Maritime Education and Training for Seafarers, (60), 33 - 38, Japanese

  • Investigation of Combustion Engines Fuelled with Alternative Plant Oil Blended with Dimethyl Ether and Gas Oil

    Tomohisa Dan

    Carbon dioxide (CO2) emission which is principal greenhouse effect gas can be reduced by using biomass as substitute fuels for combustion engines, due to its carbon neutral aspect. Among biomass, plant of Jatropha curcas whose extracted oil (Jatropha oil) is non-edible can be adoptable as an engine fuel without interfering to food oils’ market. In this study, experimental analyses were carried out in order to diminish of negative aspects of Jatropha oil (JO). Those are blending with Gas Oil (GO) and/or Dimethyl Ether (DME) to improve combustion efficiency. Test engine was a single cylinder of small bored DI diesel engine. It was modified to measure pressure histories of combustion chamber and fuel injection pressure. Also, fuel supplying line was replaced in order to use liquefied state of DME. Moreover, a long time duration test was carried out with a multiple cylinders engine. Exhaust emissions trend, as well as carbon deposit trend on valves, were observed experimentally during 200 hours run of engine. From experimental results, it is obtained that combustion pressures of blend fuels give almost equivalent trends compared to standard fuel of the engine. Emission trends, NOx and CO, also Particulate Matters (PM) are also discussed in respect to combustion efficiency.

    Mar. 2017, The 11th South East Asean Technical University Consortium (SEATUC 2017) Symposium (Ho Chi Minh), OS08-03, 1 - 5, English

    [Refereed]

    International conference proceedings

  • Combustion Analysis of Dimethyl ether / Bunker oil Blend Supplied on Line Mixing in IDI Diesel Engine

    Yu Mihara, Takashi Suzuki, Katsuya Yoshida, Ichiro Asano, Tomohisa Dan

    The exhaust gases of marine diesel engine affect marine environment. Sulfur regulation that intends to reduce both sulfur oxide (SOx) and Particulate Matter (PM) by International Maritime Organization (IMO) has been enforced since 2015 which limits sulfur content of marine fuel less than 0.1 wt.% in Emission Control Area (ECA), and the global regulation is also to be enforced in 2020 which limits the sulfur less than 0.5 wt.%. Although demands for non-sulfur alternative fuel and developments of corresponding technology are increasing, it is also expected that marine residual fuel is continuously required and used with adoption of scrubber system admitted in the regulation as optional method. This estimation depends on availability of global supply of alternative fuels. The authors have been investigating the effect of environmental burden reduction and thermal efficiency improvement by using blend fuel consists of dimethyl ether (DME) and bunker oil. In our past research, experiments have been conducted with the blend fuel made inside a high-pressure fuel tank with stirring by a rotational blade. Combustion analysis in IDI, namely pre-combustion chamber type, diesel engine was carried out, and it is shown that CO2 and NOx emissions could be reduced simultaneously by use of the blend fuel. Besides the investigation, a new continuous mixing & supplying process is being examined which aims to compound bunker oil and DME in one line instead of intermittent mixing and storing inside the high-pressure fuel tank. It is oriented to minimize an enlargement of equipment, and use the blend fuel practically on ocean going ships in near future.

    Nov. 2016, International Symposium on Marine Engineering and Technology 2016 (ISMT2016) (Busan), GS5-02, 1 - 6, English

    [Refereed]

    International conference proceedings

  • Effect of Injection Timing on Combustion and Emissions in DI Diesel Engine Fuelled with Jatopha oil / Gas oil Blends

    Wataru Hiraoka, Hideki Tanaka, Hiroki Katsura, Ichiro Asano, Tomohisa Dan

    Carbon dioxide CO2 emission which is principal greenhouse effect gas can be reduced by using biomass as substitute fuels for combustion engines. The carbon neutral explains that CO2 will be balanced between emitting by burning and absorbing by photosynthesis process. Among biomass, plant oil is one of suitable alternative fuels for diesel engines. Jatropha oil, one of plant oils, is non-edible fuel and promising alternate fuel of diesel engines. Authors are studying about blended fuel consists of Jatropha oil and gas oil. Experimental studies were carried out in order to obtain better fuel burning efficiency and cleaner emissions in four stroke direct injection diesel engine with an electric controlled fuel injection system. Jatropha oil blending ratio to gas oil (from gas oil 100% to Jatropha oil 100% changed by 10% counting range) was varied, and tendency of emission gasses also combustion pressure history were examined. From experimental results, it is obtained that combustion pressures of blend fuels give almost equivalent trends compared to gas oil, except 50% blend ratio. Emission trend, CO2 and CO, suggest that blending of Jatropha oil gives worse combustion states, and the JO blend ratio upto 50% is allowable in the range of this experimental study.

    Nov. 2016, International Symposium on Marine Engineering and Technology 2016 (ISMT2016) (Busan), GS5-01, 1 - 4, English

    [Refereed]

    International conference proceedings

  • Combustion of Ethanol Mixed Gasoline in Outboard Spark Ignition Engine

    Toru Hayakawa, Sho Nakai, Tomohisa Dan, Ichiro Asano

    Outboard engine is a compact propulsion device usually used in small size boats or fishery ships. It consists of a small-sized internal combustion engine, a driving shaft, gears and a screw propeller. Some types of outboard engines emit the exhaust emissions directly into water. If the emissions contain so much harmful substances, contamination of water environment is not avoidable. This study aims to study about alternative fuels for outboard engines. It needs to examine emissions of alternative fuels in order to avoid further pollutions. In this study, it was used an outboard engine of 2 cylinders 4 stroke spark ignition type equipped with a single propeller. It was modified to measure the exhaust emissions inducted to the atmosphere. Three type of fuels, namely Gasoline, E3 (blended 3 wt.% Ethanol), and E6 (blended 6wt.%), were examined with the engine combustion. From the experiments, it is obtained that Ethanol blending to Gasoline gives almost equivalent brake thermal efficiency compared to standard fuel of engine. Also, CO2 emission increases and CO emission decreases by blending Ethanol to Gasoline those changing ratios are proportional to the blending amounts. It is suggested that Ethanol blending gasoline will give improved combustion in the outboard engine.

    Oct. 2016, 7th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2016 (Hong Kong), 2B2-052, 1 - 6, English

    [Refereed]

    International conference proceedings

  • Combustion Analysis of Blend Fuel Consist of Jatropha Oil and Gas Oil in Diesel Engine

    Hideki Tanaka, Wataru Hiraoka, Tomohisa Dan, Ichiro Asano

    Plant oils can be recognized as the zero CO2 emission fuel based on the agreement in Kyoto protocol of UNFCCC. Authors have been studying about application methods of raw plant oil in diesel engines. In this article, Jatropha oil, one of non-edible oils, was examined for combustion and performance in a direct injection diesel engine equipped with an electric controlled fuel injection system. It was blended into gas oil in order to improve and confirm combustion states. Mixing ratios were varied, and seven different types of fuels were tested with measuring combustion pressure history and exhaust emissions. Also, fuel injection start timing was set to a retard side compared to the standard of used engine. From experimental studies, it is obtained that combustion characteristics do not change for the ignition delay trend, but change in NOx emission trend with variation in the mixing ratio. NOx emission shows lower concentration in the range of mixing ratio between 30 -70%, while it gives increased concentration both in smaller and larger mixing ratios from the range of 30 -70%. Moreover, it is suggested that those mixing ratios will give a compensation is the trade-off between NOx and PM.

    Oct. 2016, 7th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2016 (Hong Kong), 2B2-051, 1 - 6, English

    [Refereed]

    International conference proceedings

  • DME Blended Fuel Combustion in Diesel Engine with variation of Sulfur Fraction in Fuel

    Kiminobu Yoshimura, Takaaki Tanaka, Tomohisa Dan, Ichiro Asano

    Arising demands to conserve global environments, ocean going ships have been required to reduce harmful emissions, such as nitrogen oxide, sulfur oxide and so on. IMO has been issuing rules concluded by discussions at sub-committees, such as MEPC. Authors have been conducting research studies about effective methods to improve fuel combustion in diesel engines. One of effective methodology deduced from our studies is blending of liquefied Dimethyl ether (DME) to conventional fuel oils. In the present article, combustion characteristics of Marine Diesel Oil (MDO, equivalent to distillate marine fuel) were investigated in a laboratory test engine, by blending liquefied DME with variation of sulfur fraction in fuels. The sulfur fraction in fuel was varied in a wide range from 0.1 to 5.0% by weight ratios with addition of sulfur compound, Di-tert-Butyl Disulfide (DBDS). Used engine was a single cylinder four stroke direct injection diesel engine, and engine performances were measured with variation of the fuels. From the experiments, it is obtained that DME blending to MDO causes longer ignition delay compared to neat MDO case. But, ignition delay becomes shorter with increase in sulfur fraction in fuel. DME blending reduces the amount of PM as well as reduction of sulfate.

    Oct. 2016, 7th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2016 (Hong Kong), 2B2-050, 1 - 6, English

    [Refereed]

    International conference proceedings

  • Shuyi Luan, Tomohisa Dan, Ichiro Asano

    Due to requirement for keeping clean environments, strict legislations concerning emission reduction from ships are coming into force both internationally and domestically. Thus, demanding to understand combustion and emission characteristics of ship engines are still in high interests from maritime industries and institutions. This study aims to clarify a transient performance characteristic of diesel engine, especially in an engine stating period. In this article, experiments were conducted with two different types of engine, namely four stroke and two stroke diesel engines. Engine starting condition was changed with two different cases, with/without warming up. Exhaust emissions and fuel consumption were measured in variation of engine load, 50% and 75% of rated power of each engine, respectively. The findings from experiments are: 1) specific fuel consumption and CO2 emission gradually decrease, while NOx emission tends to increase and residual O2 slightly increases with time elapsing after engine start for every test case; 2) CO emission tends to decrease with elapsing time except some test cases. Those increases are supposed to be caused by CO2 thermal dissociation at activated and higher temperature condition; 3) Therefore, brake thermal efficiency is slightly increasing with elapsed time that leads to diminish portion of incomplete fuel combustion.

    Jul. 2016, Review of Graduate School of Maritime Sciences, Kobe University, (13), 9 - 17, Japanese

    Research institution

  • 栾 書奕, 段 智久, 浅野 一朗

    神戸大学大学院海事科学研究科, 2016, 神戸大学大学院海事科学研究科紀要 = Review of Graduate School of Maritime Sciences, Kobe University, (13), 9 - 17, Japanese

  • Dan Tomohisa

    Explanation article; Emulsion consist of water and fuel oil is called as Water Emulsified Fuel (WEF). Its investigation has started around 200 years ago, and it is still being examined in order to improve combustion states of fuel oils. It is known that a simultaneous reduction of NOx and Soot can be achieved by using WEF in the heat equipment those use fuel spray flame, such as diesel engines or boilers. In this article, basic characteristics of emulsion related to WEF, as well as effects of improvement in fuel combustion states by emulsification, are summarized and explained.

    The Japan Institute of Marine Engineering, 2016, Marine Engineering, 51 (3), 307 - 314, Japanese

  • Current Status and Future Vision of Education and Training with Main Engine Remote Control Simulator

    Keiji Sato, Tomohisa Dan

    Marine Technical College has been providing an education and training with a pneumatic remote control simulator since 2003. It is known that troubles with remote control systems of diesel engines will cause serious damages on ship handling. In recent years, builders of 2-stroke diesel engines have started to provide a newly developed electronically controlled engine. Ship engineers have to acquire various kinds of knowledge and skills in operations about the new type of diesel engine. It is desirable and important to use a simulator system to compensate for lack of knowledge and skill of newly developed machineries. However, an education and training program which deals with the compensations has not been established yet. This report reviews the contents and results of trainings with our remote control simulator, and proposes possible requirements and training programs for the electronically controlled engine simulator.

    Nov. 2015, The 12th International Conference on Engine Room Simulators (ICERS12) (Istanbul), 1 - 6, English

    [Refereed]

    International conference proceedings

  • RBS Analysis for ISF Components contained in PM in Exhaust Gas of Diesel Engine

    Sho Nagai, Takaaki Tanaka, Tomohisa Dan, Akira Taniike, Yuichi Furuyama

    The Japan Institute of Marine Engineering, Oct. 2015, Proceedings of the 85th Conference on Marine Engineering (Toyama), (No.103), pp.9 - 10, Japanese

    Symposium

  • Kim-Bao Nguyen, Tomohisa Dan, Ichiro Asano

    Experimental research has done to study the effects of multiple injections with variation injection timings, and amount of after injection on the combustion, performance, and emission characteristics of a modified common rail system, direct injection diesel engine fueled with neat Jatropha oil. The optimum timings for the main and after injections were between main -11,after +1.5 deg.ATDC and main -13,after -0.5 deg.ATDC. Regarding to variation of after injection amount, we found that there was significant reduction in combustion pressures and rates of heat release at lower and medium loads when large amount of after injections were employed.

    The Japan Institute of Marine Engineering, May 2015, Journal of the Japan Institute of Marine Engineering, Marine Engineering, 50 (3), 368 - 375, English

    [Refereed]

    Scientific journal

  • Kim Bao Nguyen, Tomohisa Dan, Ichiro Asano

    © 2014 Elsevier Ltd. The experimental study was carried out using a four-stroke, high speed, DI (direct-injection) diesel engine with double fuel injections. In this study, Jatropha water emulsion was made by mixing a mass ratio of 10% of water. While fixing the first injection timing, we tested the engine on JWE (Jatropha water emulsion) with various injection timings and quantities of second injections. The acquired data was analyzed for various combustion parameters such as heat release rate, combustion center (timing of 50% of total heat release), ignition delay, and combustion duration; for performance parameters such as in-cylinder temperature, exhaust gas temperature, brake thermal efficiency; and emissions of CO (carbon monoxide), CO2 (carbon dioxide), HC (hydrocarbons), NOx (nitrogen oxides), as well as dust and smoke opacity. When using a large second injection amount, we found a significant reduction in the peaks of the in-cylinder pressure, HRR (heat release rate), and average in-cylinder temperatures. We also found a drastic increase in the ignition delay, combustion duration, and a shift in the combustion center toward the later combustion stage, as well as increased exhaust gas temperatures, and reduced brake thermal efficiency compared with those of the Light oil. A large second injection amount reduced NOx emissions up to 48%, and drastically reduced HC emissions at higher loads of the engine.

    PERGAMON-ELSEVIER SCIENCE LTD, 01 Feb. 2015, Energy, 80, 746 - 755, English

    [Refereed]

    Scientific journal

  • Spray characteristics of marine diesel oil blended with liquefied dimethyl ether

    K. Matsumoto, T. Dan, I. Asano

    © 2015 International Conference on Liquid Atomization and Spray Systems. All rights reserved. Fuels used in marine diesel engines have usually higher viscosity and lower volatility, thus it is difficult to get a moderate atomization. In this study, it aims to improve an atomization of ship fuel by blending liquefied dimethyl ether (DME). A rapid evaporation of DME inside the blend fuel, so called a flashing phenomenon, is expected to enhance the atomization process. In-cylinder pressure is usually very high, so a rapid DME evaporation by pressure droppings could not be expected in real engines. However, in-cylinder temperature is also very high, especially for CI engine case, so the rapid evaporation by temperature risings could be realized. In present experiment, marine diesel oil (JIS A heavy oil) was used as a base fuel, and liquefied DME was blended inside a pressurized fuel tank. Kinematic viscosity measurement system was established to apply for the blend fuels. A transparent cylinder made of polycarbonate and two set of stainless steel flat plates were used to construct a pressure resistant cell where a capillary viscometer was inserted. The viscosity of blend fuel was measured under a pressurized ambient inside the cell while keeping DME at the liquid state. A fuel injection system which can realize a single fuel injection through a single hole nozzle (0.26mm, L/D=3) was made with combination of a fuel pump driven by a motor and a solenoid valve. The injected fuel sprays were observed and their characteristics, such as the Sauter’s mean diameter, spray angle, spray penetration, and spray volume, were measured at an atmospheric ambient condition. The droplet size was measured by an immersion liquid method. And spray was observed by a high-speed digital camera (10000 frames/sec.) with a direct photography. From experiments, it is obtained that the droplets of the DME blend fuels become smaller compared to the base fuel, and the spray angle of the DME blend fuels become larger while the penetration become shorter. And the spray volume of the DME blend fuels become larger during the fuel injection period. It is concluded that the blending of liquefied DME enhances the atomization of ship fuel.

    2015, ICLASS 2015 - 13th International Conference on Liquid Atomization and Spray Systems, (C4-1-082), 1 - 8, English

    [Refereed]

    International conference proceedings

  • Recent Study in Mixed Fuel and Biofuel for Ship Engine Application

    Tomohisa Dan

    ディーゼルエンジンの代替燃料として,混合燃料(ジメチルエーテルDME+化石燃料)およびバイオ燃料(植物油脂+化石燃料)の研究事例を紹介した。

    石油学会 ; 1978-, Jan. 2015, PETROTECH, 38 (1), 8 - 13, Japanese

  • Improvement of Diesel Spray Characteristics by Liquefied Dimethyl Ether

    松本 和人, 段 智久, 浅野 一朗

    日本液体微粒化学会, 18 Dec. 2014, 微粒化シンポジウム講演論文集, 23, 94 - 98, Japanese

  • Combustion Characteristics of Jatropha / Hydrogen Peroxide Emulsion Fuel in Diesel Engine

    Takayuki Yamamoto, Tomohisa Dan, Ichiro Asano

    In this study, an emulsification with hydrogen peroxide (H2O2) was applied to improve combustibility of Jatropha oil. Some researchers have reported that the injection of H2O2 in to combustion chambers changes the combustion states. It is expected that H2O2 generates an intermediate product, such as hydroxyl radical (OH), and combustion states will be improved. In this experiments, an emulsification of Jatropha oil with H2O2 is carried out in order to introduce the effect of combustion improvement. A horizontal water-cooled 4 stroke single cylinder diesel engine was used as a testing engine. And combustion pressure and injection pressure histories were measured, as well as exhaust emissions concentrations. As experimental results, although there are no difference in thermal efficiency in Jatropha oil and emulsion fuels, NOx and CO2 emissions are reduced with the emulsified fuel case compared to the neat Jatropha oil case. Also, it is obtained that the ignition delay of the emulsified fuel becomes shorter compared to the neat Jatropha oil. From those combustion characteristics changes, it is concluded that H2O2 enhances the combustion of plant oil.

    Oct. 2014, 6th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2014 (Hangzhou), (NTMI-02), 1 - 6, English

    International conference proceedings

  • Combustion Analysis of Jatropha Oil / Marine Diesel Oil Mixed Fuel in Direct Injection Diesel Engine

    Naoto Katayama, Tomohisa Dan, Ichiro Asano, Yasuyuki Kori, Koji Kanno

    In this study, engine operation experiments have been carried out by using Jatropha oil. The used engine was a single cylinder four-cycle direct-injection diesel engine. The short-term performance test was done in variation of mixing ratio of Jatropha oil to fossil oil (A-heavy oil which is equivalent to Marine diesel oil). And the long-term performance test was done with continuously running the engine (40 hours) to confirm a durability. As result of various performance tests, it was clarified that the refined Jatropha oil (washed with flesh water) which mixed 10 weight percent to A-heavy oil can operate the engine without any major troubles.

    Oct. 2014, 6th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2014 (Hangzhou), (NTMI-01), 1 - 6, English

    International conference proceedings

  • Combustion Analysis of Bunker Oil DME Mixed Fuel in Pre-combustion Chamber Type Diesel Engine

    Katsuya Yoshida, Yasuhiro Nishimura, Tomohisa Dan, Ichiro Asano

    In this research, the reduction effect of environmental pollutant contained in exhaust gas was investigated with the fuel which mixed di-methyl ether (DME) to bunker oil. In the past research, the experiments using the same fuel in a small direct-injection diesel engine were conducted. This time, the larger size and pre-combustion type diesel engine was used for the experiments. As results, the thermal efficiency is improved and CO, HC and PM were sharply decreased by mixing DME. On the other hand, reduction effect of NOx was not found clearly.

    Sep. 2014, 10th International Symposium on Marine Engineering (ISME 2014 Harbin), (PID105), 1 - 6, English

    [Refereed]

    International conference proceedings

  • Combustion Analysis of Diesel Engine Fueled with DME/MDO Added Sulfur Component

    Takahiro Hisashiba, Tomohisa Dan, Ichiro Asano

    In this study, a four-stroke high-speed direct injection diesel engine fueled with MDO for baseline data and mixture of 30% of DME to MDO with an addition of Di-tert-Butyl Disulfide (DBDS) of 3.5% and 5.0% were investigated to clarify the effect of sulfur content. The results of experiments confirm that ignition delay decreased with an increase of the sulfur ratio in fuel, consequently, reduced NOx emissions. Insoluble fraction (ISF) was increased by an increase of sulfate, while total PM emission was reduced.

    Sep. 2014, 10th International Symposium on Marine Engineering (ISME 2014 Harbin), (PID106), 1 - 5, English

    [Refereed]

    International conference proceedings

  • Identification of sulfur species adsorbed on particulate matters from ship exhaust gas using XAFS analyses

    Satoshi Asaoka, Hideo Okamura, Tomohisa Dan, Hisayo Okamoto, Shinjiro Hayakawa

    ディーゼルエンジンから排出される粒子状物質(Particulate Matters, PM)にはさまざまな有害物質が含有される。その中で,燃料中の硫黄分は水と反応して硫酸塩(サルフェート)としてPMに吸着されると言われている。本研究では,A重油100%と,A重油にDMEを混合した次世代燃料について,模擬硫黄化合物(DBDS)を添加した場合のPMを解析した。解析は重量法による定量解析と,XAFS(X線)解析を行った。その結果,DME混合によってPM重量が減少すること,PMに含まれる硫黄化合物の分子構造形態を明らかにした。

    Sep. 2014, Proceedings of the 18th Hiroshima International Symposium on Synchrotron Radiation, 18, 151 - 152, English

    [Refereed]

    International conference proceedings

  • Kim Bao Nguyen, Tomohisa Dan, Ichiro Asano

    © 2014 Elsevier Ltd. Recently, Jatropha, a fast growing tropical plant, has caught the attention of researchers because the oil produced from Jatropha is a non-edible. However, worse emissions, when using raw Jatropha oil in diesel engines, have been reported in the literature due to its higher viscosity and lower volatility. Therefore, it is necessary to find some way to reduce the emissions of diesel engines. In the present research, experiments have been designed and performed to study the effects of Jatropha hydrogen peroxide emulsion on combustion, performance, and the emission characteristics of a diesel engine. Hydrogen peroxide in a solution of water at a concentration of 30% was used for making the emulsions with mixing mass ratios of 5%, 10%, and 15%. A single cylinder, four-stroke, high speed, direct injection diesel engine was used for the experiments. The acquired data were analyzed for various combustion parameters such as in-cylinder pressure, ignition delay, ignition duration, heat release, for performance parameters and emissions of CO, CO2 (carbon dioxide), HC, NOx, and PM as well. While running the engine on the Jatropha hydrogen peroxide emulsion fuel, improvements in performance and emissions were found and the optimum mixing ratio of the solution with hydrogen peroxide was 15%.

    PERGAMON-ELSEVIER SCIENCE LTD, 2014, Energy, 74 (C), 301 - 308, English

    [Refereed]

    Scientific journal

  • Evaluation Method of Energy Saving Operation in Marine Engine Plant System by Using Engine Room Simulator

    Keiji Sato, Tomohisa Dan

    It has been becoming very important to consider an environmental conservation in the ship operation to overcome the high oil prices and the severe legislations in exhaust emission levels. The engine plant simulator (ERS) has been used to train the seafarers, but the point of energy conservation is lacking. In this study, the relation formula between the ship operation conditions and the exhaust emissions are introduced to the ERS, and a concept of energy saving operation of the ERS is proposed.

    Oct. 2013, The 11th International Conference on Engine Room Simulators (ICERS11 Busan), 31 - 39, English

    [Refereed]

    International conference proceedings

  • Diesel spray and combustion characteristics of liquefied dimethyl ether mixing fuel

    Dan Tomohisa, Ouchi Ryota, Nishimura Yasuhiro, Asano Ichiro

    In this study, the effects of DME mixing were examined with engine combustion and spray atomization analyses in variation of the nozzle opening pressure. From the engine experiments, it is obtained that the ignition timing becomes later in case of DME mixing for the lower nozzle opening pressure. The amount of smoke decreases by DME mixing among wide range of engine speed (1200 to 2200 rpm). NOx emission can be reduced by DME mixing, and shows the smallest exhaust amount in case of the lower nozzle opening pressure case. From the spraying experiments, it is obtained that the Sauter mean diameter becomes smaller with increasing in DME mixing ratio and nozzle opening pressure. Also, the spray angle and the spray volume increase in proportional to DME mixing ratio.

    Kobe University, Jul. 2013, Review of Graduate School of Maritime Sciences, Kobe University, 10 (10), 54 - 61, Japanese

  • Younghyun Ryu, Tomohisa Dan

    Fossil fuels are the dominant source of energy today with the problem of their supply depletion becoming a global issue. Since stable energy supplies are necessary in order to sustain the activities of mankind, conservation of petroleum fuel and finding an appropriate substitute are critical. Additionally, solutions to global environmental pollution problems are simultaneously needed, such as the Kyoto protocol for global warming. The aim of this study is to investigate whether the combustion state of bunker oil can be improved by the mixing of DME (dimethyl ether), which is considered as a possible alternative fuel. The kinematic viscosity of DME blended fuel, as well as the engine performance characteristics of single cylinder direct injection diesel engine, was measured experimentally. In the kinematic viscosity measurement, a pressure cell type viscosity measurement system was established in order to apply the volatile DME blended fuel. The nozzle opening pressure was changed in order to obtain different injection characteristics in the diesel engine. For diesel engine applications, DME has a problem of poor lubricity due to its lower viscosity and Bunker oil has the problems of exhaust emissions and high viscosity. of special note, Bunker oil needs to be heated up over 100 degrees centigrade to reduce its viscosity applicable for marine diesel engine use. In the present study, Bunker oil can be used without heating in diesel engines by mixing with DME. Copyright © 2013 SAE International and Copyright © 2013 KSAE.

    2013, SAE Technical Papers, 11, 1 - 10, English

    [Refereed]

    International conference proceedings

  • Dan Tomohisa, Oue Masaki, Nishimura Yasuhiro, Asano Ichiro

    The authors have investigated the effects of liquefied Dimethyl Ether (DME) mixed with conventional fuels of diesel engines. From those studies, it was clarified that DME mixing can drastically reduce unburned exhaust emissions, such as CO, HC and Particulate Matter (PM). However, the effect of sulfur content in fuels was not clearly examined. In this study, combustion analysis was carried out by varying sulfur ratio in fuels using a small size direct injection four stroke diesel engine. The test fuels were low sulfur Marine Diesel Oil (MDO, JIS A heavy oil) and MDO/DME mixed fuel. Di-t-butyl Disulfide (DBDS) was added to change the sulfur component ratio of those fuels. Experimental results obtained show that the injection duration and the specific fuel consumption increase with increasing the sulfur ratio in fuels, while the ignition delay decreases with an increase in sulfur ratio. Results also show that even though the sulfur content was increased, NOx emission and PM emission were reduced with DME mixing. It is assumed that the transfer rate of sulfur in fuel to sulfate in PM is in the range of 1.0 to 2.4% for MDO base fuel, and 0.4 to 0.9% for DME mixed fuel.

    The Japan Institute of Marine Engineering, 2013, Marine Engineering, 48 (5), 676 - 683, Japanese

  • 段 智久, 尾内 亮太, 西村 裕大, 浅野 一朗

    神戸大学大学院海事科学研究科, 2013, 神戸大学大学院海事科学研究科紀要 = Review of Graduate School of Maritime Sciences, Kobe University, (10), 54 - 61, Japanese

  • DAN Tomohisa, RYU Younghyun, ASANO Ichiro

    Diesel engines have been used as power sources of the propulsion as well as the electric generator for oceangoing vessels.Although they have advantages in the thermal efficiency and the durability compared to other types of internal combustion engines,their exhaust gases contain harmful substances, such as the nitrogen oxide, the sulfur oxide or the particulate matter, which cause the environmental pollutions. Dimethyl Ether (DME) has been paid attention as one of alternative fuels of the diesel engine, since it emits less soot emission compared to the fossil fuels. Thus, various studies have been done that use neat DME as the fuel oil of diesel engines. The aim of this study is to clarify whether liquefied DME mixed with Bunker C (JIS C heavy oil) could improve the engine performance of diesel engine. In the present study, a pressure resistant fuel tank was made to mix liquefied DME and Bunker C, and a direct injection type of diesel engine was used to analyze the combustion characteristics. From the experiments, it is obtained that the ignition delay can be shorten with mixing DME to Bunker C. Also, DME mixed fuel can reduce the incomplete combustion substances, such as the carbon monoxide, the unburnt hydrocarbons and the soot. Moreover, it can diminish the amount of the carbon dioxide emission with DME mixed fuel while keeping almost the same thermal efficiency with neat Bunker C.

    The Japan Society of Naval Architects and Ocean Engineers, 01 Dec. 2012, Journal of the Japan Society of Naval Architects and Ocean Engineers, 16 (16), 197 - 205, Japanese

  • Impact of Dimethyl Ether to Ship Engine Fuel for Marine Environment Protection

    Tomohisa Dan, Younghyun Ryu, Ichiro Asano

    In this report, the measurement system of volatile DME is described in detail. Also, an engine combustion test is also carried out in variation of injection rates. The fuel injection rates were controlled by the changing of the nozzle opening pressure. From the experiments, it is obtained that the lower nozzle opening cases showed enhanced combustion states by mixing DME. Also, mixing DME to Bunker oil showed the reduced kinematic viscosity compared to the neat Bunker oil.

    Dec. 2012, 5th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2012 (Taipei), SEPAS-03, 1 - 6, English

    [Refereed]

    International conference proceedings

  • Investigation of Jatropha Oil Fueled Diesel Engine with Split Injection

    Kim-Bao Nguyen, Shota Tanaka, Tomohisa Dan, Ichiro Asano, Masataka Hashimoto

    Multiple injections were tested in order to optimize a combustion state of Jatropha oil in a diesel engine. It is aimed that raw Jatropha oil can be utilized in a DI diesel engine. In this study, a two-stage injection was tested in variation of injection fuel quantity and timing. As the results, it is obtained that the smaller amount of after injection and the advanced fuel injection timing give the better exhaust emissions in case of a small size DI diesel engine used in this study.

    Dec. 2012, 5th Pan Asian Association of Maritime Engineering Societies, Advanced Maritime Engineering Conference 2012 (Taipei), GT-05, 1 - 5, English

    [Refereed]

    International conference proceedings

  • Combustion and Emission Characteristics of Diesel Engine by Mixing DME and Bunker Oil

    Younghyun Ryu, Tomohisa Dan

    Succeeding paper about the research in liquefied DME mixing to Bunker oil. In this article, a detail analysis of mixed fuel combustion in a diesel engine is reported. The mixing ratio of DME to Bunker oil was varied in the range of 0, 20 and 40%, and effects of mixing ratio to combustion states were measured. As the result, it is obtained that the imperfect combustion fractions, such as CO, HC and Smoke can be reduced by mixing DME. Also, CO2 can be diminished in a certain condition.

    Nov. 2012, Journal of the Korea Society of Marine Engineering, 36 (7), 885 - 893, English

    [Refereed]

    Scientific journal

  • Younghyun Ryu, Tomohisa Dan, Ichiro Asano

    In previous papers of authors, it is shown that the mobility of fuel can be enhanced by mixing liquefied Dimethyl Ether (DME) to Bunker oil. And a pre-heating of fuel is not necessary which is required for conventional ship fuels. In this article, the viscosity measurement system is established to get kinematic viscosity values of volatile fuels. And the kinematic viscosity of the mixed fuel comprised of liquefied DME and Bunker oil is measured in variation of mixing ratio and fuel temperature. It is obtained that the viscosity is drastically reduced within an exponential formula by the DME mixing.

    The Japan Institute of Marine Engineering, Sep. 2012, Journal of the Japan Institute of Marine Engineering, Marine Engineering, 47 (5), 729 - 734, English

    [Refereed]

    Scientific journal

  • Analysis of Two-stage Injection Diesel Engine by Using Engine Numerical Simulation Code

    Dan Tomohisa, Asa Shingo, Asano Ichiro

    Subsequent report about the analytical study by the numerical simulation code (HIDECS). In this report, the details of injection pressure history are discussed for the case of split injection. The accuracy of calculation results is improved by the revised input fuel injection conditions. Especially, the coefficient of nozzle discharge is estimated by measurements of injected fuel mass and pressure histories. As the result, the combustion histories with different fuel types, such as gas oil or Jatrpha oil, are successfully evaluated with the optimized simulation conditions.

    Kobe University, Jul. 2012, Review of Graduate School of Maritime Sciences, Kobe University, 9 (9), 26 - 32, Japanese

  • Reforming of Bunker Oil by Using Dimethyl Ether : Viscosity Measurement of Blending Fuel Containing Volatile Component

    段 智久, 柳 榮鉉, 水庫 誠

    日本船舶海洋工学会, May 2012, 日本船舶海洋工学会講演会論文集, (14), 121 - 124, Japanese

  • Diesel Engine Combustion with Fuels Next Generation

    DAN Tomohisa

    Explanation article. The next generation fuels for ship engines, such as Biofuel or Dimethyl Ether (DME), are studied experimentally. For Biofuel, the utilization of raw plant oil by mixing with lighter fossil fuels are explained, as well as the mixing liquefied DME to fossil fuels, those are effective to reduce harmful emissions including the CO2 emission.

    日本液体微粒化学会, 31 Mar. 2012, ATOMIZATION : Journal of the ILASS-Japan, 21 (72), 12 - 19, Japanese

  • DAN Tomohisa

    Explanation article. The research papers are reviewed that treat the usage of non-esterified plan oils in diesel engines including the results of author. Problems will not be occurred so much in the plant oil usage with ship engines where the coarse fuel, such as Bunker oil, is usually used. Pre-heating of plant oils or mixing with fossil fuels is effective to reduce the high viscosity of plant oils. Also, the water emulsification will realized better combustion, especially reduction of carbon deposits.

    The Japan Institute of Marine Engineering, 01 Jan. 2012, Marine Engineering, 47 (1), 51 - 58, Japanese

  • 段 智久, 阿佐 信吾, 浅野 一朗

    神戸大学大学院海事科学研究科, 2012, 神戸大学大学院海事科学研究科紀要 = Review of Graduate School of Maritime Sciences, Kobe University, (9), 26 - 32, Japanese

  • DAN Tomohisa

    Presentation of the experimental study about utilization of non-esterified plant oil (Jatropha curcas oil) in a diesel engine. In this report, experimental results of water emulsified Jatropha oil are described for the case of direct injection type diesel engine equipped with an electrical controlled injection system. The fuel injection start timing must be advanced due to the longer ignition delay when the water mixing ratio is increased. As the result, an increment in the NOx emission is not avoidable with the advanced timings, but the soot emission can be diminished while keeping the thermal efficiency at same value.

    Japan Institute of Navigation, 2012, NAVIGATION, 180 (0), 68 - 73, Japanese

  • Diesel Combustion of Water Emulsified Jatropha Curcas Oil

    色見 晃輔, 段 智久, 浅野 一朗

    日本船舶海洋工学会, Nov. 2011, 日本船舶海洋工学会講演会論文集, (13), 321 - 324, Japanese

  • Combustion and Emission Characteristics of Diesel Engine by Mixing DME and Marine C Heavy Fuel Oil

    Younghyun Ryu, Tomohisa Dan, Makoto Mizukura, Ichiro Asano

    DME (Dimethyl Ether) is regarded as one of the candidates of alternative fuels for diesel engine, because of its higher cetane number suitable for a compression ignition engine. Also, DME is clean, colorless gas that is easy to be liquefied and transported. On the other hand, HFO (C heavy Fuel Oil) has been used as the basic fuel in marine diesel engines which is the lowest grade oil in the fuel oils. In this study, the combustion and emission characteristics were measured experimentally in direct injection type diesel engine operated with DME and HFO mixed fuel. From experimental results, it is induced that DME and HFO blended fuel would be a future marine fuel which can reduce the concentration of harmful matters in exhaust gases.

    Oct. 2011, 9th International Symposium on Marine Engineering (ISME Kobe 2011), D2-1, 1 - 6, English

    [Refereed]

    International conference proceedings

  • Engine Performance Analysis of Two Stage Injection Diesel Engine by Numerical Simulation Code HIDECS

    Shingo Asa, Tomohisa Dan, Ichiro Asano

    Although diesel engines have excellent features, such as higher thermal efficiency and durability, their exhaust gases contain harmful matters, namely NOx, SOx and PM. One of the counter measures to reduce those harmful matters is a multiple fuel injection system which becomes possible with an electric control unit, so called a common rail injection system. In the present study, the engine performances of two stage fuel injection, such as combustion pressure histories and exhaust gas emissions, have been investigated by experiments with a real engine and by a numerical simulation. The numerical simulation code utilized in this study is HIDECS which can calculate the engine performances with a superposition of empirical equations. The engine performances of two stage injection were examined in variation of fuel type, such as gas oil, marine diesel oil and bio-fuels.

    Oct. 2011, 9th International Symposium on Marine Engineering (ISME KOBE 2011), A1-3, 1 - 5, English

    International conference proceedings

  • Can Dimethyl Ether Diminish Environmental Impacts of Diesel Exhaust Particulates from Marine Diesel Oil?

    Hideo Okamura, Takuya Sawamoto, Tomohisa Dan, Hirotsugu Fujita

    Dimethyl ether (DME) can be added to marine diesel oil (MDO) or heavy fuel oil (HFO) to reduce green house gas emissions and diesel exhaust particulates (DEP=PM). The aim of this study was to clarify whether addition of DME to MDO or HFO could reduce environmental impacts of DEP in terms of toxic chemicals and toxicity. The soluble organic fraction (SOF) of DEP, obtained from MDO or HFO with 30% blending of DME at four engine loads (25, 50, 75, 100 %), was subjected to chemical analysis of polycyclic aromatic hydrocarbons and nitrated PAHs and to mutagenicity and ecotoxicity assays. Addition of DME to MDO or HFO resulted in reduction of PM, total PAHs, and 1-nitropyrene in weight per kWh, with some exceptions at different engine load and fuel used. DME addition to MDO also reduced mutagenicity and ecotoxicity, however, HFO with DME significantly enhanced mutagenicity and ecotoxicity at some conditions.

    Oct. 2011, 9th International Symposium on Marine Engineering (ISME Kobe 2011), C5-3, 1 - 4, English

    International conference proceedings

  • Combustion Characteristics of Water Emulsified Jatropha Curcas Oil in Variation of Water Droplet Distribution

    Kousuke Shikimi, Tomohisa Dan, Ichiro Asano, Masataka Hashimoto

    Jatropha curcas has been paid attention in recent years, because it is an ideal seed for bio fuel which is not edible and contains higher amount of fats. The aim of this study is whether water emulsification of Jatropha curcas oil could improve combustion characteristics in a diesel engine. In experiments, tap water is mixed to Jatropha curcas oil by using several surfactants and two types of W/O emulsion fuels are made in variation of water drop diameter distribution profile. From the combustion analysis with a pre-combustion chamber type diesel engine, it is obtained that both types of water emulsified fuels can reduce NOx emission and improve the thermal efficiency. Reduction rate of NOx emission is changed with engine load condition. In case of uniform droplet diameter emulsion fuel, the reduction rate was smaller in higher engine load, where it became larger in lower engine load.

    Oct. 2011, 9th International Symposium on Marine Engineering (ISME Kobe 2011), D2-1, 1 - 6, English

    [Refereed]

    International conference proceedings

  • Incorporation of Malfunctions in Equipment in Marine Engine Plant Simulator

    Tomohisa Dan, Makoto Uchida, Hiromasa Ikawa, Yasunaga Maeda, Akira Sou

    In the present study, it is aimed to incorporate malfunctions of marine plant system with the Marine Engine Plant Simulator (MEPS). The data of practical malfunctions of ship equipment, 3,399 incidents with 1,395 ships, were gathered in corporation with an organization of marine engine operations. Those data were analyzed in aspect of the founding method of errors. From the data analysis, it is induced that sever damages on ship equipment tend to be found by mechanical methods while damages found by human inspections tends to be slight ones. Namely, the watch by marine engineers can avoid a severe damage of equipment for the safe ship operation. This results are now been tried to incorporate with our MEPS.

    Sep. 2011, The 10th International Conference on Engine Room Simulators (ICERS10 St.Petersburg), (11), 1 - 8, English

    [Refereed]

    International conference proceedings

  • MIYAWAKI Naoya, DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro

    From the viewpoints of limited fuel oil resources and the problem of global warming, possible alternatives to fossil oil have been widely studied in recent years. Jatropha curcas oil is one of the vegetable oils considered as possible alternatives to fossil fuel. It is effective in reducing CO2 emissions with its carbon-neutral characteristic, and it does not contribute to the problem of increasing food prices because its seeds are poisonous and are thus inedible. This study aims to clarify whether water emulsification can improve the combustion characteristics of Jatropha curcas oil. The experiments were conducted with water-to-Jatropha curcas oil ratios of 5%, 10%, 15%, and 20% by weight, and combustion analysis was carried out. The test engine used was a 4-stroke pre-combustion chamber type diesel engine which can generally run on poor quality fuels. Combustion pressure and fuel injection pressure as well as exhaust gas emissions were measured. It was shown that water emulsification resulted in the improvement of thermal efficiency and the reduction of NOx emissions and carbon deposits.

    The Japan Institute of Marine Engineering, 01 Sep. 2011, Marine Engineering, 46 (5), 752 - 757, Japanese

  • Diesel Engine Performance of DME-C Heavy Oil Mixed Fuel

    段 智久, 水庫 誠, 柳 榮鉉

    日本船舶海洋工学会, May 2011, 日本船舶海洋工学会講演会論文集, (12), 21 - 24, Japanese

  • DAN Tomohisa

    エステル化処理をしてない生のバイオ燃料(ジャトロファ油脂)をディーゼルエンジンで有効に利用する方法を解説。高粘度のジャトロファ油にA重油を混合することで動粘度を下げることができ,また予燃焼室式ディーゼルエンジンを用いて混合燃料の燃焼解析を行った結果,熱効率をA重油100%の場合とほぼ同程度に維持しながら運転可能であることを明らかにしたことについて解説。

    Japan Institute of Navigation, 2011, NAVIGATION, 177 (0), 52 - 57, Japanese

  • Effects of Combustion and Emission Characteristics in Diesel Engine Operated with DME-Bunker C Blend Fuel

    Younghyun Ryu, Tomohisa Dan, Kazuya Ishida, Ichiro Asano

    Recently, controlling of air pollutant emissions from diesel engine has become more important issue. Diesel engines have been used as power sources in many ships, because of their high thermal efficiency and durability. However, the diesel engine produces harmful exhaust gas emissions, such as NOx or PM(Particulate Matter), those are considered as the matter which brought the air pollution. Thus, it is needed to reduce such harmful matters to agree with the level set by the legislation(IMO environmental pollution regulation).
    In this study, the engine performance, emission characteristics of the mixed fuel comprised of DME(Dimethyl Ether) and Bunker C was experimentally examined. DME is simple chemical structure and high oxygen content(34.8%wt.) which result in no PM(or soot) combustion in the engine. Bunker C has been used as the basic fuel in marine diesel engines. It is the lowest grade oil in the fuel oils. For this experiment, a small high-speed direct injection single cylinder diesel engine was used as the test engine. It has been compared exhaust gas emissions(NOx, PM, Smoke, HC, O₂, CO, CO₂) through experimental examined by change of the engine revolution number and the load.
    This study confirmed the possibility of using DME-Bunker C Blend Fuel in marine diesel engine.

    Dec. 2010, 4th Pan Asian Association of Maritime Engineering Society (PAAMES), Advanced Maritime Engineering Conference 2010, P003 (No.6.2.1), 345 - 350, English

    International conference proceedings

  • Hiroshi Oshio, Tomohisa Dan, Masataka Hashimoto, Ichiro Asano

    Recently, alternative fuels are actively studied all over the world. The main reasons are the depletion of crude oil, soaring oil prices and the global warming problem. Biomass fuel is one of the most up and coming alternative fuels from the viewpoint of carbon neutrality. The problem with biomass fuel is that it creates competition between food and fuel. Thus, the authors considered Jatropha which is a non-food plant. Its seed contains phorbol ester which is toxic and thus is inedible. The combustion analysis of Jatropha oil mixed with Marine diesel oil was studied. A 4-stroke pre-combustion chamber type compression ignition engine was used because of its ability to handle inferior fuels. Increasing the mixture ratio of Jatropha oil resulted in reduced NOx emissions and a decreasing tendency of smoke opacity. Each fuel showed an approximately equal value of thermal efficiency. The results show that in a pre-combustion chamber type compression ignition engine, the Jatropha oil and blended fuel can be used as an alternative fuel to MDO.

    The Japan Institute of Marine Engineering, Oct. 2010, Journal of the Institute of Marine Engineering, 45 (Special Isuue), 50 - 55, English

    [Refereed]

    Scientific journal

  • DAN Tomohisa

    液化ジメチルエーテルを多種の燃料に混合して燃焼改善を行う技術に関する研究について,これまでの結果をまとめて解説したもの。廃食用油,A重油などに液化ジメチルエーテルを混合した場合の燃噴射圧力・燃焼圧力履歴,排ガス成分,燃料噴霧可視化画像などの研究結果を紹介し,ジメチルエーテルによって燃料の広域拡散,燃焼の活性化が行われ,結果としてディーゼルエンジンの機関性能が改善できることを解説した。

    Japan Institute of Navigation, 2010, NAVIGATION, 175 (0), 78 - 83, Japanese

  • HASHIMOTO Masataka, DAN Tomohisa, ASANO Ichiro, OTANI Tomohito

    Palm oil is being seriously looked at as one of the alternative fuels to fossil fuels, this being due to the aspect of vegetable oils and the so called carbon neutral state. However, at room temperature, the viscosity of palm oil is too high to apply as a fuel for the internal combustion engine. In this study, pure palm oil is mixed with fossil fuels, this in order to reduce the viscosity. In the experiment palm oil was blended with gas oil and then marine diesel oil, by weight ratio, and the kinematic viscosity of the mixed fuels were measured. In the cases of 20% palm oil used, and 50%, was found to be useable without any heating of the fuels. Engine performances, such as cylinder pressure histories and exhaust emissions, were examined with a pre-combustion chamber type diesel engine. We discovered that a palm oil blended fuel shows earlier ignition and shorter combustion period than gas oil or marine diesel oil. NOx emissions show a lower concentration for all palm blended cases, and the reduction ratio is proportional to the palm mixing amount. From these results, we can suggest that palm oil could be used for the diesel engine by mixing with the fossil fuels without heating the fuels.

    The Japan Institute of Marine Engineering, 01 May 2009, Marine Engineering, 44 (3), 456 - 462, Japanese

  • DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro, OKUMURA Teppei, SUZUKI Naoki

    DME is the simplest ether and consists of oxygen and methyl. Because of its chemical and physical properties it is thought that DME could be one of the candidates as an alternative fuel in the internal combustion engine. The authors have been investigating the combustion characteristics of the mixed fuel comprising of Dimethyl ether and Marine Diesel Oil (JIS A-heavy oil). In the experiments, DME is mixed at the liquefied state with MDO inside a high pressure fuel tank pressured with nitrogen gas. Fuel supply lines are replaced with pressure resistant tubes, and the mixed fuel is supplied to the small direct injection diesel engine. We obtained the effect on the fuel injection characteristics to the mixed fuel combustion, in the diesel engine. The two different fuel injection rates are obtained by changing the injection nozzle opening pressure, that for the relatively lower case (9.0MPa) and higher (24.0MPa). The fuel injection pressure histories and the combustion characteristics, such as the combustion pressure and the exhaust emission, are examined for both the injection conditions. The average injection pressure increased with increased engine load in the lower nozzle opening pressure case. Whilst it is almost constant with the higher nozzle opening pressure case. It was concluded that ignition delay could be shortened by DME mixing. And NOx emissions were reduced in the higher engine load case, and with mixing DME for both nozzle opening pressure cases.

    The Japan Institute of Marine Engineering, 01 Mar. 2009, Marine Engineering, 44 (2), 322 - 327, Japanese

  • Tomohisa Dan, Masataka Hashimoto, Ichiro Asano, Akira Kunikawa

    Diesel engine has been used as a power source in many fields, because of its high thermal efficiency and durability. But its exhaust gas emissions, such as NOx or Particulate Matter, are considered as the matter which brought the air pollution. Thus, it is needed to reduce such harmful matters to agree with the level set by the legislation. In this study, the engine performance of the mixed fuel comprised of DME (Dimethyl Ether) and marine diesel oil was experimentally examined. Because of the molecule properties of DME, it emits no soot in combustion. At the atmospheric condition, DME can be liquefied with rising in its pressure. When liquefied DME is injected in combustion chambers, the flashing energy is supposed to be useful as the atomization of other liquid fuels. A small high-speed direct injection diesel engine was used as the test engine. Its bore and stroke were 92mm and 96mm, and the compression ratio was 17.7. The fuel pump was jerk type and was utilized without major modifications. The engine was operated at 4 different speeds with variation in the engine load. From experiments, the ignition delay becomes shorter with increase with the mixing ratio of DME. The smoke emissions were reduced for every engine load condition with mixing DME. From experimental results, it is concluded that DME is useful for reducing in the smoke emission in the diesel engine combustion. Copyright © 2007 Society of Automotive Engineers of Japan, Inc.

    2007, SAE Technical Papers, SAE 2007-01-2014, English

    [Refereed]

    International conference proceedings

  • DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro, NAKAMURA Takurou

    Dimethyl Ether (DME) was mixed with waste vegetable oil to improve combustion and exhaust emissions in a high speed diesel engine. Past research has shown that the properties of DME, such as lower boiling point and higher cetane number, would affect atomization process and combustion progress of DME/Marine diesel oil blending fuel. In this study, the effect of mixing DME with waste vegetable oil was investigated by using the 4-stroke single cylinder direct injection diesel engine. The combustion pressure history, injection pressure, exhaust gas emissions were measured in variation with mixing ratio of DME and engine load. The emissions of smoke and nitrogen oxide were found to reduce with increase in mixing ratio of DME.

    The Japan Institute of Marine Engineering, 01 May 2006, Marine Engineering, 41 (3), 438 - 443, Japanese

  • DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro, NAKAMURA Takurou

    In previous paper, we improved the diesel engine system to use DME (Di-Methyl Ether) as fuel oil. The engine performance using the mixed fuel comprised of DME and Marine diesel oil was reported. In this report, further investigation was carried out in varying mixing ratio of DME and Marine diesel oil. In the experiments, combustion pressure, rate of heat release, pollutant emissions and injection condition were measured using a small high-speed single-acting 4 stroke diesel engine. A high-speed video camera was used to investigate the fuel spray pattern. As a result, it is shown that the ignition delay becomes shorter by increasing the mixing ratio of DME to Marine diesel oil. Fuel spray spreads wider in radial direction in case of higher mixing ratio of DME. Due to the changes in combustion history and spray pattern, concentration of soot and CO emission become smaller by increasing the mixing ratio of DME to Marine diesel oil.

    The Japan Institute of Marine Engineering, 01 Nov. 2005, Marine Engineering, 40 (6), 820 - 826, Japanese

  • HASHIMOTO Masataka, DAN Tomohisa, ASANO Ichiro, KUBO Takashi

    The edible oil (food-grade vegetable oil) that has been wasted about 400,000 ton per year from home and factories use will be able to use for a fuel oil of diesel engines. It will be useful as a recycling, so we tried to use for the diesel engine (YANMAR-3ESDL). The experiment was conducted by three patterns. The first was of using some blended fuels which were mixed with waste edible oil and diesel fuel by several ratios. The second was changing the injection timing from -10 deg. to -14 deg. C.A (B.T.C), and then, delayed to -8 deg. The third was heating of the waste edible oil for reducing the viscosity index to the level of diesel fuel. And the tests were tried in the condition of 20kPa charged air, constantly from idling to full load. The data of exhaust gas analysis and the engine performance were recorded, and then compared with normal performances by using of diesel fuel. As for the blended fuel of the waste edible oil and diesel fuel, a carbon deposit was seen until the low mixing rate of waste edible oil. Therefore, it is necessary to clean up fuel injection nozzles and cylinders periodically. So the desirable percentage of the waste edible oil in the blended fuel will be 30vol% or less for use. The carbon deposit was accumulated around the hole of injection nozzles or the cylinder. Moving forward the injection timing, the injection period became longer. So the deposit was increased. But, by heating waste edible oil at 100℃, an injection pattern of atomization became better, so the combustion got better, too, and the carbon deposit almost couldn't be seen, and then low NOx and smoke condition were performed.

    Kobe University, Jul. 2004, Review of the Faculty of Maritime Sciences, Kobe University, 1 (1), 99 - 106, Japanese

  • DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro, YAMAGATA Masafumi

    We improved the system of a high-speed single-acting 4-stroke diesel engine to allow it run on a mixed fuel comprised of A-heavy oil and DME (Di-Methl Ether), fuel components that discharge no soot, no SOx, and little NOx in combustion. The combustion pressure, rate of heat release, exhaust gas components, and other conditions were measured in experiments using diesel oil, A-heavy oil, and the mixed fuel comprised of DME and A-heavy oil.
    As a result, the ignition timing was earliest with diesel oil, median with the mixed fuel, and latest with A-heavy oil. Mixed fuel discharged a slightly reduced level of NOx. Overall, results indicated that the engine would require further improvements before long-term operation became possible.

    The Japan Institute of Marine Engineering, 01 Jun. 2004, Marine Engineering, 39 (6), 409 - 414, Japanese

  • HASHIMOTO Masataka, DAN Tomohisa, ASANO Ichiro, KOU Ri

    Gas turbines are well known as clean thermal engine systems, and they offer the advantages of availability for multiple fuel types and of a continuous combustion system. These engine systems have not been as popular as they might be because of their low thermal efficiency. Recently, however, thanks to development of co-generation and combined cycles, the gas turbine system has been reconsidered.
    This report concerns an experiment on a simple open chamber gas turbine using a heavy oil mixed fuel blended with waste cooking oil, and using a mixed fuel in which water and a surface-active agent were blended in order to purify the exhaust emissions and to save energy, respectively. Exhaust emission ingredients were measured and analyzed. The additional effect of mixed fuel, such as rapeseed oil, was compared and examined.

    The Japan Institute of Marine Engineering, 01 Feb. 2004, Marine Engineering, 39 (2), 148 - 152, Japanese

  • Monitoring Technique in Combustion Pressure (Combustion History via Oscillating Equation)

    Hashimoto Masataka, Dan Tomohisa, Asano Ichiro[et al.]

    シリンダヘッドに加工を施さず,比較的簡単な手段によって燃焼圧力の変化を推定する方法について報告したもの。シリンダのスタッドボルトにひずみゲージを貼り付け,そのひずみ量の時間変化を計測して燃焼圧力を振動モデルによって推定するものである。その結果,モデルのバネ定数を適宜補正することで,実際の指圧線図に近い推定値を得ることが可能であることを示した。

    Kobe University, Jul. 2003, Review of Kobe University of Mercantile Marine. Part II, Maritime studies, and science and engineering, 51 (51), 91 - 95, Japanese

  • HASHIMOTO Masataka, DAN Tomohisa, ASANO Ichiro, CHO Sin-yo

    Vegetable oils such as alcohol, rape-seed oil, etc., are well-known as alternative fuels in the near future. But they have low performance, especially long ignition delay and low calorific value, for use as a fuel of diesel engines. So we tried to improve better performance by mixing with petroleum.
    This report shows the application availability of the Laser speckle interferometry to the fixed combustion chamber in the former, and the ignition difference about each fuel's droplet by use of this interferometry in the latter.
    The performance analysis was something made clear, but the specification of temperature field in each combustion process was not clear by the disturbance of ignition ray, smoke and soot.

    The Japan Institute of Marine Engineering, 01 Mar. 2003, Marine Engineering, 38 (3), 169 - 175, Japanese

  • HASHIMOTO Masataka, DAN Tomohisa, ASANO Ichiro, OH Teppu

    A gas turbine is well known as a clean thermal engine system, and it has an advantage of availability for multi-kinds fuels as a continuous combustion system. But it has not been popularized so much by its own low thermal efficiency. Recently, arranging the co-generation and the combined cycle, the gas turbine system has been reconsidered.
    In this report, we have investigated the availability of vegetable oils as a blender to a fuel for making good use of a gas turbine.
    After all, a waste oil (vegetable oil) was a good blender to a A -heavy fuel. The performance has good con-ditions.

    The Japan Institute of Marine Engineering, 01 Mar. 2003, Marine Engineering, 38 (3), 164 - 168, Japanese

  • Basic Studies of Diesel Spray

    DAN TOMOHISA

    解説記事。ディーゼル噴霧の微粒化過程に関する機構や実験結果,数値予測などについて解説した特集記事。液体の微粒化に関する研究の歴史を総説し,微粒化に用いられる無次元パラメータについて解説した。また,エンジンにおける燃料噴霧のうち,ディーゼル燃料噴霧について,その内部構造を解析した結果を紹介した。また,噴霧の数値計算によるモデリングについても解説を行った。

    Sep. 2002, Engine Technology : SANKAIDO, 4 (5), 40 - 45, Japanese

    [Invited]

    Scientific journal

  • Masataka Hashimoto, Tomohisa Dan, Ichiro Asano, Takeshi Arakawa

    Some volumes of gas oil and ethanol were mixed to the rape-seed oil to examine the engine performance characteristics. A 4-cycle indirect injection diesel engine was used as the test engine, and exhaust emissions were measured together with cylinder pressure history in variation of the engine loads. The single droplet combustion test was also carried out. Combustion processes in the heated constant volume vessel were observed by using of a high-speed video camera. From the experiments, it is obtained that rape-seed oils take longer combustion duration compared with gas oils. And addition of ethanol promotes the micro explosion of fuel droplets. These features affect to the properties of exhaust emissions from the engine. Copyright © 2002 Society of Automotive Engineers, Inc.

    2002, SAE Technical Papers, No.2002-01-0867, 1 - 12, English

    [Refereed]

    International conference proceedings

  • Jung Kuk Yeom, Koichi Ashida, Jiro Senda, Hajime Fujimoto, Tomohisa Dan

    This study proposes a hybrid model which consists of modified TAB(Taylor Analogy Breakup) model and DVM(Discrete Vortex Method). In this study, the simulation process is divided into three steps. The first step is to analyze the breakup of droplet of injected fuel by using modified TAB model. The second step based on the theory of Siebers' liquid length is analysis of spray evaporation. The liquid length analysis of injected fuel is used for connecting both modified TAB model and DVM. The final step is to reproduce the ambient gas flow and inner vortex flow injected fuel by using DVM. In order to examine the hybrid model, an experiment of a free evaporating fuel spray at early injection stage of in-cylinder like conditions had been executed. The numerical results calculated by using the present hybrid model are compared with the experimental ones. The calculated results on gas jet flow by DVM quantitatively well correspond to the experimental results for the downstream of evaporative spray. It is also confirmed that an ambient gas flow occupies the downstream region flow in diesel spray. Copyright © 2001 Society of Automotive Engineers, Inc.

    2001, SAE Technical Papers, No.2001-01-1240, 1 - 13, English

    [Refereed]

    International conference proceedings

  • Qin Jian-Rong, Dan Tomohisa, Lai Ming-Chia, Savonen Craig, Schwartz Ernest, Brkyzik Walter

    This paper studies the effect of nozzle geometry on the flow characteristics inside a diesel fuel injection nozzle and correlates to the subsequent atomization process under different operating conditions, using simple turbulent breakup model. Two kinds of nozzles, valve covered orifice (VCO) and mini-SAC nozzle, with various nozzle design parameters were studied. The internal flow inside the nozzle was simulated using 3-D computational fluid dynamics software with k-ε turbulence model. The flow field at the nozzle exit was characterized by two parameters: the fuel discharge coefficient Cd and the initial amplitude parameter amp0. The latter parameter represents the turbulence characteristics of the exit flow. The effects of nozzle geometry on the mean velocity and turbulent energy distribution of the exit flow were also studied. The characteristics of the exit flow were then incorporated into the spray model in KIVA-II to study the effect of nozzle design on diesel spray behavior. The results show that the nozzle geometry has a strong influence on the flow field inside the nozzle and the subsequent process of atomization. Copyright © 1999 Society of Automotive Engineers, Inc.

    Kobe University, Mar. 2000, Bulletin of Kobe University of Mercantile Marine, 1, 167 - 181, English

    [Refereed]

  • E307 EFFECT OF SULFUR COMPOUND IN FUEL OIL TO ENGINE PERFORMANCE AND EXHAUST EMISSION(Engine performance) :

    DAN Tomohisa, FUJITA Hirotsugu, HASHIMOTO Masataka, NISHIDA Osami, AN Sukheon

    Recently, the effect of fuel composition is investigated for reducing participate matters [1][2] and sulfuric oxides [3][4]. But several problems are remaining unable to be solved as matters stand. This paper studies the effect of sulfur compound on the combustion characteristics of diesel engine. In the experiments, DBDS(Di-tert, Butyl, Di-Sulfide) were mixed to the base fuel to vary the amount of sulfur compound in fuel oils. The direct injection diesel engine was operated with several test fuels taking the change in exhaust gases as well as cylinder pressure histories. The calorific value of each test fuels was also examined. It is obtained that the more DBDS mixed to the base fuel, the calorific value becomes lower thus the fuel consumption tends to be larger. The results suggest that the molecular structure of SOx has a strong influence on the PM emission, where the soluble organic fraction in PM reduces along with increasing of the sulfur mixed ratio.

    日本機械学会, 2000, Proceedings of the ... JSME-KSME Thermal Engineering Conference, 3 (0), "3 - 409"-"3-414", English

  • KUSANO Shigeyuki, DAN Tomohisa, SENDA Jiro, FUJIMOTO Hajime

    In this study, new models on the new droplet evaporation taking account of the droplet surface temperature related to the modified Spalding model, on the ambient temperature and the mass fraction at the infinite-point was proposed and incorporated into KIVA-II code. These models were compared and reviewed with the droplet evaporation model of KIVA-II original code in relation to the standard Spalding model. As a results, it is found that the calculated results of droplet evaporation by new model agree well with actual phenomena.

    The Japan Society of Mechanical Engineers, 1999, TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B, 65 (630), 804 - 811, Japanese

    [Refereed]

  • TAKAGISHI Sayo, TAKAHASHI Tomohiro, DAN Tomohisa, SENDA Jiro, FUJIMOTO Hajime

    The characteristics of combustion process in internal combustion engines are affected by mixing process between the injected fuel and the ambient gas. Therefore, it is necessary to understand the flow field in diesel fuel sprays. In this study, a single spray was injected into a quiescent atmosphere with room temperature at high pressure through a single hole nozzle for simplification. To discuss the flow field in diesel sprays, structure of the spray was visualized by laser light sheet method. And, it was revealed that the vortex structure inside the spray affects the classification of droplet particles by taking microscopic photographs of the droplets with high resolution film. And applying PIV method into the spray photography, both the formation of meandering structure of the spray mainstream and the ambient gas entrainment process are clarified.

    The Japan Society of Mechanical Engineers, 1999, TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B, 65 (631), 1128 - 1133, Japanese

    [Refereed]

  • Flow Characteristics in a Transient Spray by Means of PIV

    Hajime Fujimoto, Sayo Takagishi, Tomohiro Takahashi, Tomohisa Dan, Jiro Senda

    本論文は,噴霧の微粒化機構を明らかにすることを目的に,噴霧の内部構造をレーザシート散乱光によって連続撮影をし,画像相互を粒子追跡法によって解析した結果を報告した。燃料噴射期間中の液滴密度の高い領域は解析できなかったが,噴霧の先端部および燃料噴射期間終了後の液滴密度が低い領域に渦度を有する旋回流動が存在することを明らかにした。その結果,仮想していた噴霧モデルを裏付ける実験結果を得ることができた。

    Dec. 1998, International Conference on Optical Technology and Image Processing in Fluid, Thermal, and Combustion Flow (VSJ-SPIE '98), AB003, English

    [Refereed]

    International conference proceedings

  • Transient Characteristics of High-Pressure Diesel Sprays

    Tomohisa Dan, Ming-Chia.Lai, T.C. Wang, Xing-bin Xie

    噴霧の乱れによる分裂過程を実験および数値計算によって解析したもの。ノズル近傍の噴霧を長焦点距離のレンズを使って拡大顕微鏡撮影し,ドラムカメラを用いた撮影でその時間変化について実験的にとらえた。また,数値計算を各種の噴霧分裂モデル別に行って結果を比較し,噴射期間中に休息期間があるような噴射率波形に関しては,モデルの最適化が必要であることを提起した。

    Jul. 1998, 4th Int’l Symposium on Diagnostics and Modeling of Combustion in Internal Combustion Engines COMODIA 98 (Kyoto), 471 - 476, English

    [Refereed]

    International conference proceedings

  • Measurement in Spray Density and Fuel Vapor in Diesel Spray via Laser Light Sheet

    DAN Tomohisa

    噴霧内部の燃料蒸発過程を計測できるエキサイプレックス蛍光法について報告。その原理や特許について詳説し,同手法を適用した蒸発噴霧の計測結果を示した。この手法は,2種類の化学物質を燃料に混合し,一方の化学物質は燃料の蒸発特性に近いものを選択して用いる。噴霧にレーザー光を照射すると,それぞれの蛍光波長が異なることから,液体・気体の同時分離撮影が可能となる。

    高温学会, 20 May 1998, Journal of High Temperature Society., 24 (3), 96 - 101, Japanese

  • Modeling of Turbulent Primary Breakup in Diesel Spray

    Tomohisa Dan, Ming-Chia Lai

    ディーゼル噴霧などの高速液体噴流をモデル化する場合,ノズル内部での燃料流乱れなどが分裂に寄与する。これを初期分裂(Primary Breakup)と称するが,従来の噴霧モデリングでは理論的にこの影響を考慮していない。そこで,本論文の研究では,KIVA-IIコード(Los Alamos製)で噴霧の初期乱れを設定するパラメータについて,ノズル内部の数値計算コード(STAR-CD)の解析とリンクさせて,モデル定数を理論的に与える手法について提唱した。

    Feb. 1998, 8th International Engine Combustion Multidimensional Modeling Conference at the SAE Congress, 1 - 8, English

    [Refereed]

    International conference proceedings

  • SENDA Jiro, SHIBATA Ichiro, DAN Tomohisa, FUJIMOTO Hajime

    This study investigates the atomization mechanism of fuel spray dissolved in noncondensable gas, such as N_2,CO_2. The fuel spray was injected at room temperature and in an atmospheric pressure field through a diesel-hole-type nozzle. In this paper, N_2 gas was dissolved into diesel fuel, n-tridecane, under several pressurized conditions using a gas bubbling method in a constant volume vessel. This fuel, with high gas solubility, was injected under several injection pressures using an accumulated injection system designed by the authors. It was found that the dissolved gas separated into gas bubbles like gas cavitation phenomena under the atmospheric field. The change in spray patterns caused by the gas solubility is discussed using photographs of the patterns.

    The Japan Society of Mechanical Engineers, 25 Sep. 1997, Transactions of the Japan Society of Mechanical Engineers. Series B., 63 (613), 3173 - 3178, Japanese

  • Spray Characteristics of Non-Reacting Diesel Fuel Spray by Experiment and Simulations with KIVA II Code

    Jiro Senda, Tomohisa Dan, Sayo Takagishi, Tomoyuki Kanda, Hajime Fujimoto

    静止雰囲気場における微粒化した燃料液滴群を実験的および数値計算によって解析したもの。噴霧の微粒子の分散について,噴霧全体の平均粒子直径ならびに局所断面の粒子直径を透過光減衰法によって実験的に測定した。燃料の噴射圧力を変化させて実験を行い,噴射圧力の上昇にともなって粒子直径が小さくなること,局所の粒子直径分布の変動が小さくなることなどを得ている。

    Aug. 1997, 7th International Conference on Liquid Atomization and Spray Systems, I of II, 149 - 156, English

    [Refereed]

    International conference proceedings

  • Fuel Flow Characteristics and Cavitation Phenomena in Nozzle of Diesel Spray by Planer Acrylic Model

    Jiro Senda, Tomohisa Dan, Takehiro Yamamoto, Hajime Fujimoto

    噴霧の微粒化に与える燃料流のノズル内部での挙動を明らかにするために,基礎実験として二次元のアクリル製のモデルノズルを作成して燃料流の計測を行った。その結果,ノズル先端部の燃料溜まり容積部(サック部)で燃料流動が循環流を形成することをとらえ,この循環流とノズルホールへ流れ込んでいく燃料流が干渉して乱れを生じさせていることを明らかにした。

    Aug. 1997, 7th International Conference on Liquid Atomization and Spray Systems, I of II, 215 - 222, English

    [Refereed]

    International conference proceedings

  • Tomohisa Dan, Sayo Takagishi, Jiro Senda, Hajime Fujimoto

    This paper deals with the particle distribution in Diesel spray under the non-evaporating condition from the analytical aspect based on our experimental results. In the analysis, TAB method of KIVA II code and the k-ε turbulent model were used, and the mono-disperse distribution of the initial parcel's diameter, whose size equals to the nozzle hole diameter, was utilized in conjunction with the breakup model. The size distribution of atomized droplets (i.e. the χ-squared distribution function) is justified with the degree of freedom. It is shown that the ambient gas, which is initially quiescent, is induced and led to a turbulent gas jet. The turbulent gas jet which has a equivalent momentum with the Diesel spray was also examined by Discrete Vortex method. The quantitative jet growth was shown to be possible for the estimation and determination in its initial boundary values at the nozzle. Copyright © 1997 Society of Automotive Engineers, Inc.

    1997, SAE Technical Papers, No.970641, 265 - 278, English

    [Refereed]

    International conference proceedings

  • Tomohisa Dan, Takehiro Yamamoto, Jiro Senda, Hajime Fujimoto

    The spray structure under the pressurized atmosphere at a room temperature was examined by the various photographic methods. The fuel flow inside the nozzle was investigated by the transparent model nozzles. The experimental analysis of sprays yielded the spray dispersing angle, the distribution of fuel droplets inside the spray and the jet intact core length. The obtained results of those spray characteristics showed that the spray structure is divided into two spatial regimes due to their formation mechanisms. Within 10 mm from the nozzle, the spray dispersion is dominated by the turbulent states of fuel which are initiated inside the nozzle. At distance from the nozzle z > 20 - 40 mm, the spray consists of an induced gas vortex street whose length is about half of the spray width. It is proposed that the kinematic viscosity of ambient gas is a important factor which rules the process of momentum exchange form the fuel jet to the ambient gas. Copyright © 1997 Society of Automotive Engineers, Inc.

    1997, SAE Technical Papers, No.970355, 259 - 274, English

    [Refereed]

    International conference proceedings

  • Tomohisa Dan, Sayo Takagishi, Jiro Senda, Hajime Fujimoto

    In this paper, spray characteristics were examined to deduce the effect of ambient gas properties. Considered ambient properties were the viscosity μa and density ρa, and thus the kinematic viscosity νa. The objective of this paper is to reveal the effect of compressibility of the ambient gas to spray formation. In the experiments, the changed ranges were And a standard-sac volume nozzle of hole diameter d n =0.25 mm (ln/dn=3.0) was used at constant injection pressure difference (Δp=16.2 MPa). Also the injection pressure was varied in the range of 55 to 120 MPa with a mini-sac volume nozzle of hole diameter dn =0.20 mm (ln/dn =5.5). Several different gases were used to change the ambient viscosity at a room temperature. From the experiments, it is obtained that larger the viscosity, the more the spray spreads in the radial direction, thus the spray angle gets larger and the tip penetration became shorter. And atomized droplets become smaller with larger ambient viscosity at the same density. It is concluded that the kinematic viscosity should relate to the phenomenon of diesel fuel spray under different ambient conditions. Copyright © 1997 Society of Automotive Engineers, Inc.

    1997, SAE Technical Papers, No.970352, 219 - 234, English

    [Refereed]

    International conference proceedings

  • SENDA Jiro, SHIBATA Ichiro, DAN Tomohisa, FUJIMOTO Hajime

    This study investigates the atomization mechanism of fuel spray dissolved in noncondensable gas, such as N2, CO2. The fuel spray was injected at room temperature and in an atmospheric pressure field through a diesel-hole-type nozzle. In this paper, N2 gas was dissolved into diesel fuel, n-tridecane, under several pressurized conditions using a gas bubbling method in a constant volume vessel. This fuel, with high gas solubility, was injected under several injection pressures using an accumulated injection system designed by the authors. It was found that the dissolved gas separated into gas bubbles like gas cavitation phenomena under the atmospheric field. The change in spray patterns caused by the gas solubility is discussed using photographs of the patterns.

    The Japan Society of Mechanical Engineers, 1997, TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B, 63 (613), 3173 - 3178, Japanese

    [Refereed]

  • J. Senda, T. Dan, T. Yamamoto, H. Fujimoto

    This paper presents the experimental analysis on the fuel flow states inside the transparent model nozzle. The cross sectional configuration of an actual hole-type Diesel nozzle (dn = 0.20 mm, ln/dn = 3.75) was similarly magnified in length scale of the factor 2 (dm = 0.40 mm) and 10 (dm = 2.0 mm). The both model nozzles are 5 mm in thickness and put between flat plates. The fuel flow states were observed by a high-speed framing video camera. Also cavitation phenomenon were obtained by an instantaneous video photography with the back diffusion light illumination method. The discharge coefficient and the spray cone angle were measured in variation of injection pressures up to 2 MPa. The correlation of the results was discussed with the cavitation number K', which is defined as K'=pa/Δp.

    1997, International Journal of Fluid Mechanics Research, 24 (1-3), 380 - 388

    [Refereed]

    Scientific journal

  • DAN Tomohisa, TAKAGISHI Sayo, OHISHI Naoki, SENDA Jiro, FUJIMOTO Hajime

    This study deals with the effect of the viscosity of the ambient gas on the atomization process of a diesel spray. The liquid fuel is injected through a single-hole nozzle (ln/dn=0.75 mm/0.25 mm)with the injection differential pressure of 16.2 MPa inside a constant-volume vessel under a high-pressure field at room temperature. In practical combustion chambers of diesel engines, the viscosity of the ambient gas varies mainly with its temperature. In this experiment, various gases (CO_2, N_2, Ar, Ne, and Ar+Ne) were utilized for the ambient atmosphere in order to change the ambient gas viscosity. The vaporization of fuel drops was negligible. This study, revealed that the higher the viscosity, the more the spray spreads in the radial direction, thus the spray angle increased and tip penetration decreased. The droplets became smaller and were distributed in the inner region of the cold-state diesel spray under high ambient viscosity conditions. Further more, it was found that processes of ligament formation in the liquid jet and initial atomization were affected by kinematic viscosity ratio between the liquid fuel and ambient gas, and the spray dispersion and mixing process in the downstream region was affected only by the ambient gas kinematic viscosity.

    The Japan Society of Mechanical Engineers, 25 Jul. 1996, Transactions of the Japan Society of Mechanical Engineers. Series B., 62 (599), 2867 - 2873, Japanese

  • DAN Tomohisa, TAKAGISHI Sayo, OHISHI Naoki, SENDA Jiro, FUJIMOTO Hajime

    In the experiments presented here, a single diesel spray of n-tridecane was injected for a certain duration through a hole-type nozzle (l_n/d_n=1.1mm / 0.2mm) into a quiescent high pressure atmosphere at room temperature. We used the same amounts of fuel injection for each injection pressure and the same ambient gas density field for all injection experiments including tests of the effect of changing the ambient gas. The macroscopic spray structures were observed by instantaneous photography and using a high-speed video camera system. Furthermore, the microscopic structure was observed by means of laser light-scattering photography, fuel droplet distribution was measured using the laser light-sheet of a pulsed Nd-YAG laser, and the mean diameter of the drop was obtained through image processing by the laser extinction method. This study revealed that the diesel spray consisted of a number of large vortices, which was considered to be the coherent structure. With high ambient gas viscosity, the fuel droplet became smaller. It was also found that a large vortex existed at the tip of the spray.

    The Japan Society of Mechanical Engineers, 25 May 1996, Transactions of the Japan Society of Mechanical Engineers. Series B., 62 (597), 2079 - 2085, Japanese

  • Spatial Structure in Free Spray Frow from Momentum Conservation Aspect

    Dan Tomohisa, Takagishi Sayo, Senda Jiro, Fujimoto Hajime

    ディーゼル燃料噴霧は,液体燃料がノズル出口部で持つ運動量が,周囲気体に交換されることで保存される(運動量理論)ことは既に知られているが,本論文は運動量の保存が角運動量による(渦核による)ことを提唱した。雰囲気の気体にさまざまな種類の媒体を用いた場合の実験解析結果,また数値計算コードによる解析結果から,運動量が回転する渦度によって保存される可能性があることを示した。また,流体が球体剛体粒子の抵抗におよぼす速度指数の影響についても論じている。

    Doshisha University, Mar. 1996, The Science and engineering review of Doshisha University, 36 (4), 225 - 251, Japanese

  • DAN Tomohisa, TAKAGISHI Sayo, OHISHI Naoki, SENDA Jiro, FUJIMOTO Hajime

    In the experiments presented here, a single diesel spray of n-tridecane was injected for a certain duration through a hole-type nozzle (ln/dn=1.1mm / 0.2mm) into a quiescent high pressure atmosphere at room temperature. We used the same amounts of fuel injection for each injection pressure and the same ambient gas density field for all injection experiments including tests of the effect of changing the ambient gas. The macroscopic spray structures were observed by instantaneous photography and using a high-speed video camera system. Furthermore, the microscopic structure was observed by means of laser light-scattering photography, fuel droplet distribution was measured using the laser light-sheet of a pulsed Nd-YAG laser, and the mean diameter of the drop was obtained through image processing by the laser extinction method. This study revealed that the diesel spray consisted of a number of large vortices, which was considered to be the coherent structure. With high ambient gas viscosity, the fuel droplet became smaller. It was also found that a large vortex existed at the tip of the spray.

    The Japan Society of Mechanical Engineers, 1996, TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B, 62 (597), 2079 - 2085, Japanese

    [Refereed]

  • DAN Tomohisa, TAKAGISHI Sayo, OHISHI Naoki, SENDA Jiro, FUJIMOTO Hajime

    This study deals with the effect of the viscosity of the ambient gas on the atomization process of a diesel spray. The liquid fuel is injected through a single-hole nozzle (ln/dn=0.75 mm/0.25 mm)with the injection differential pressure of 16.2 MPa inside a constant-volume vessel under a high-pressure field at room temperature. In practical combustion chambers of diesel engines, the viscosity of the ambient gas varies mainly with its temperature. In this experiment, various gases (CO2, N2, Ar, Ne, and Ar+Ne) were utilized for the ambient atmosphere in order to change the ambient gas viscosity. The vaporization of fuel drops was negligible. This study, revealed that the higher the viscosity, the more the spray spreads in the radial direction, thus the spray angle increased and tip penetration decreased. The droplets became smaller and were distributed in the inner region of the cold-state diesel spray under high ambient viscosity conditions. Further more, it was found that processes of ligament formation in the liquid jet and initial atomization were affected by kinematic viscosity ratio between the liquid fuel and ambient gas, and the spray dispersion and mixing process in the downstream region was affected only by the ambient gas kinematic viscosity.

    The Japan Society of Mechanical Engineers, 1996, TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B, 62 (599), 2867 - 2873, Japanese

    [Refereed]

  • Dan Tomohisa, Ohishi Naoki, Senda Jiro, Fujimoto Hajime

    In the experiments presented, a single diesel spray of n-tridecane was injected for a certain duration through a hole-type nozzle into a quiescent atmosphere at room temperature at high pressure. The experimental variables were nozzle hole dimensions such as the hole diameter dn, the hole length ln and the hole offset between the nozzle axis and the hole axis, and the nozzle needle lift, in order to assess the turbulent flow field inside the nozzle, and the other was the back pressure, in order to examine the effect of the ambient gas properties, especially its kinematic viscosity. The macroscopic spray structures were observed by using instantaneous photography and a high-speed video camera system. Furthermore, the microscopic structure was observed by meant of scattering photography of fuel droplets taken by the laser light sheet of a pulsed ruby laser, and the quantitative 2-D image of fuel concentration in the cross section of the spray containing its central axis was obtained by the image processing. From the experiments, the variation in the spray cone angle with the needle lift is promoted by the turbulence in the sac volume, and spray angle is closely related to the ambient kinematic vincosity.

    The Japan Society of Mechanical Engineers, 1994, TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B, 60 (577), 3192 - 3197, Japanese

    [Refereed]

MISC

  • 藤野 俊和, 野村 昌孝, 井上 順広, 前田 和幸, 川原 秀夫, 小島 隆志, 大出 剛, 三輪 誠, 角 和芳, 吉田 肇, 北原 辰巳, 段 智久, 氏平 信輔, 林 祐亮, 西尾 澄人, 鈴木 信宏

    The Japan Institute of Marine Engineering, 2020, Marine Engineering, 55 (4), 457 - 471, Japanese

  • Dan Tomohisa, Yoo Dong-Hoon

    The Japan Institute of Marine Engineering, 2020, Marine Engineering, 55 (1), 136 - 139, Japanese

  • Report on 8th PAAMES / AMEC2018

    段 智久, 船津 賢人

    日本マリンエンジニアリング学会, May 2019, Marine engineering : journal of the Japan Institute of Marine Engineering = マリンエンジニアリング :日本マリンエンジニアリング学会誌, 54 (3), 143 - 146, Japanese

  • 藤野 俊和, 野村 昌孝, 井上 順広, 前田 和幸, 川原 秀夫, 小島 隆志, 大出 剛, 三輪 誠, 角 和芳, 吉田 肇, 北原 辰巳, 段 智久, 柿木 隆宏, 林 祐亮, 西尾 澄人, 鈴木 信宏

    The Japan Institute of Marine Engineering, 2019, Marine Engineering, 54 (4), 552 - 567, Japanese

  • Dan Tomohisa

    The Japan Institute of Marine Engineering, 2019, Marine Engineering, 54 (2), 281 - 282, Japanese

  • Dan Tomohisa, Funatsu Masato

    The Japan Institute of Marine Engineering, 2019, Marine Engineering, 54 (3), 459 - 462, Japanese

  • Iwamoto Katsumi, Inoue Norihiro, Dan Tomohisa, Toda Shinichi, Shibata Shigeyuki

    The Japan Institute of Marine Engineering, 2018, Marine Engineering, 53 (3), 299 - 313, Japanese

  • Dan Tomohisa

    The Japan Institute of Marine Engineering, 2018, Marine Engineering, 53 (3), 329 - 329, Japanese

  • 地引 達弘, 鵜飼 英実, 井上 順広, 前田 和幸, 三原 伊文, 小島 隆志, 大出 剛, 角 和芳, 吉田 肇, 北原 辰巳, 段 智久, 山口 拓哉, 瀧本 崇弘, 西尾 澄人, 梶田 哲郎

    The Japan Institute of Marine Engineering, 2018, Marine Engineering, 53 (4), 528 - 543, Japanese

  • Dan Tomohisa

    The Japan Institute of Marine Engineering, 2017, Marine Engineering, 52 (6), 766 - 770, Japanese

  • 地引 達弘, 中村 英孝, 高橋 千織, 前田 和幸, 井上 順広, 三原 伊文, 小島 隆志, 角 和芳, 吉田 肇, 福田 勝哉, 段 智久, 花本 健一, 萩原 和也, 山田 淳司, 塚本 達郎

    The Japan Institute of Marine Engineering, 2016, Marine Engineering, 51 (4), 462 - 475, Japanese

  • Dan Tomohisa

    The Japan Institute of Marine Engineering, 2016, Marine Engineering, 51 (3), 259 - 259, Japanese

  • Dan Tomohisa

    The Japan Institute of Marine Engineering, 2016, Marine Engineering, 51 (3), 260 - 262, Japanese

  • Dan Tomohisa

    The Japan Institute of Marine Engineering, 2016, Marine Engineering, 51 (5), 593 - 594, Japanese

  • 段 智久

    神戸大学大学院海事科学研究科, 2012, 海事博物館研究年報 = Annual bulletin of Maritime Museum, 40 (40), 14 - 17, Japanese

  • 数値シミュレーション

    高崎 講二, 田島 博士, 馬場 真二, 段 智久

    01 Jul. 2010, Marine engineering : journal of the Japan Institution of Marine Engineering = マリンエンジニアリング : 日本マリンエンジニアリング学会誌, 45 (4), 486 - 487, Japanese

  • Harada Tomohiro, Kajita Tetsuroh, Sudoh Seiji, Amamiya Norikazu, Hayashi Toshiaki, Yoshida Satoru, Sumi Kazuyoshi, Yoshida Hajime, Shimizu Etsuroh, Hiroya Harino, Takasaki Kohji, Sasaki Sennichi, Tajime Hiroshi, Dan Tomohisa, Baba Sinji, Harumi Kazuyoshi, Senda Tetsuya, Kondo Morio, Utoh Seiji, Itami Yoshiharu, Nishiue Hitoshi, Iizuka Satoshi

    The Japan Institute of Marine Engineering, 2010, Marine Engineering, 45 (4), 438 - 487, Japanese

  • Dan Tomohisa

    The Japan Institute of Marine Engineering, 2010, Marine Engineering, 45 (1), 130 - 133, Japanese

  • その他

    千田 哲也, 高崎 講二, 段 智久, 馬場 真二, 田島 博士

    01 Jul. 2009, Marine engineering : journal of the Japan Institution of Marine Engineering = マリンエンジニアリング : 日本マリンエンジニアリング学会誌, 44 (4), 543 - 544, Japanese

  • Hukuda katsuya, Dan Tomohisa

    The Japan Institute of Marine Engineering, 01 May 2009, Marine Engineering, 44 (3), 485 - 485, Japanese

  • Harada Tomohiro, Sudoh Seiji, Amamiya Norikazu, Terada Minoru, Komatsu Yasuyuki, Nomura Takeshi, Yoshida Hajime, Oshio keisuke, Shutoh Hideki, Takasaki Kohji, Tajime Hiroshi, Sasaki Sennichi, Dan Tomohisa, Baba Sinji, Harumi Kazuyoshi, Senda Tetsuya, Akimoto Seita, Utoh Seiji, Itami Yoshiharu, Nishiue Hitoshi, Nomura Shuji

    The Japan Institute of Marine Engineering, 2009, Marine Engineering, 44 (4), 498 - 544, Japanese

  • 数値シミュレーション

    高崎 講二, 馬場 真二, 段 智久, 田島 博士

    01 Jul. 2007, Marine engineering : journal of the Japan Institution of Marine Engineering = マリンエンジニアリング : 日本マリンエンジニアリング学会誌, 42 (4), 547 - 547, Japanese

  • 原田 朋宏, 椎原 裕美, 千田 哲也, 春海 一佳, 宮崎 修二, 田嶋 保則, 伊丹 良治, 西上 均, 立石 智裕, 萩原 正久, 那口 行輝, 梶田 哲郎, 小松 泰幸, 長沼 伯之, 吉田 肇, 久保 晴義, 梶原 修平, 清水 悦郎, 千田 哲也, 高橋 一暢, 張野 宏也, 岡村 秀雄, 前田 和幸, 高崎 講二, 馬場 真二, 段 智久

    The Japan Institute of Marine Engineering, 01 Jul. 2006, Marine Engineering, 41 (4), 520 - 564, Japanese

  • 高井 元弘, 倉本 智, 原田 朋宏, 畔津 昭彦, 川上 雅由, 橋本 正孝, 田島 博士, 田辺 秀明, 西田 恵哉, 高崎 講二, 小川 英之, 植木 弘信, 段 智久, 戸田 伸一, 岩本 勝美, 浜武 俊朗, 北原 辰巳, 若月 祐之, 千田 哲也, 角 和芳, 梶田 哲郎, 塚本 達郎, 小俣 重雄, 高橋 千織, 久保 晴義, 冨田 展久, 佐々木 千一, 伊藤 邦憲, 波津久 達也, 城田 英之, 近藤 宏一, 五島 正雄, 平岡 克英, 平田 宏一, 村田 航, 宮崎 恵子, 沼野 正義, 間島 隆博, 上田 浩一, 吉田 靖

    The Japan Institute of Marine Engineering, 01 Mar. 2006, Marine Engineering, 41 (2), 176 - 187, Japanese

  • Participating Essays on ISME TOKYO 2005

    KIFUNE Hiroyasu, MIYAZAKI Keiko, FUJITA Hirotsugu, DAN Tomohisa, MISHIMA Takashi, HASHIMOTO Takeshi

    日本マリンエンジニアリング学会, 01 Mar. 2006, Marine engineering, 41 (2), 205 - 208, Japanese

  • YME Delegation and Subsequent Activity(1) : Spread in Research Activity

    DAN Tomohisa

    01 Jul. 2005, Marine engineering : journal of the Japan Institution of Marine Engineering = マリンエンジニアリング : 日本マリンエンジニアリング学会誌, 40 (4), 503 - 504, Japanese

  • Discussion with YME Members-Activities and Future Prospects

    DAN Tomohisa

    01 Mar. 2003, Marine engineering : journal of the Japan Institution of Marine Engineering = マリンエンジニアリング : 日本マリンエンジニアリング学会誌, 38 (3), 156 - 157, Japanese

  • YME2001;低環境負荷ディーゼルエンジン技術の調査研究

    段 智久

    日本マリンエンジニアリング学会, 01 Jun. 2002, Marine engineering : journal of the Japan Institution of Marine Engineering = マリンエンジニアリング : 日本マリンエンジニアリング学会誌, 37 (6), 3 - 6, Japanese

  • 平成13年度YME使節員帰朝報告・討論会

    段 智久

    日本マリンエンジニアリング学会, 01 Jun. 2002, Marine engineering : journal of the Japan Institution of Marine Engineering = マリンエンジニアリング : 日本マリンエンジニアリング学会誌, 37 (6), 34 - 37, Japanese

Books etc

  • Principles of Sea Transportation

    Edit by Kobe, University Principle of Sea Transportation Committee, 神戸大学海上輸送の三原則編集委員会

    Contributor, Chapter 2, Part 2, KAIBUNDO, Jul. 2013, Japanese, 「海上輸送の安心・安全な運航」と「海洋・大気環境負荷の低減」ならびに「海上輸送の経済性」の3つの要素を「海上輸送の三原則」と捉え、これらを統合した新分野の開拓を神戸大学海事科学研究科と経済・経営学研究科の教員らが協力して進めている。本書では、上述した海上輸送に係る3つの要素についての最新の取り組みを、研究グループの担当者が平易に解説している。, ISBN: 4303164100

    Scholarly book

  • DAN Tomohisa

    Single work, Disertation Thesis of Doshisha University, Self Piblished, Mar. 1997, Japanese, 請求記号 UT51-97-D210 国立国会図書館書誌ID 000000306477 永続的識別子 info:ndljp/pid/3121290

    [Refereed]

    Others

Presentations

  • Alternative fuel combustion

    Tomohisa Dan

    The 6th International Conference on Marine Technology (SENTA 2021), 27 Nov. 2021, English

    [Invited]

    Keynote oral presentation

  • Research on the application of alcohol fuel in outboard engine spark ignition engine

    Tokushi Ito, Kodai Nakano, Wataru Miyazaki, Eisuke Nishikawa, Hideo Okamura, Tomohisa Dan, Ichiro Asano

    90th (Reiwa 2) Marine Engineering Academic Conference, 28 Oct. 2020, Japanese, The Japan Institute of Marine Engineering, Fukuoka, Japan, Domestic conference

    Oral presentation

  • Study on the imitation listening rod system development for Sensory ERS

    Hiromasa Ikawa, Takashi Miwa, Tomohisa Dan

    90th (Reiwa 2) Marine Engineering Academic Conference, 26 Oct. 2020, Japanese, The Japan Institute of Marine Engineering, Fukuoka, Japan, Domestic conference

    Oral presentation

  • Bio Fuel Combustion toward GHG Reduction

    DAN Tomohisa

    International Symposium on Marine Engineering and Technology (ISMT2019 Busan), Special Session 3, 24 Oct. 2019, English, International conference

    [Invited]

    Invited oral presentation

  • Effect of Droplet Diameter Distribution in Water Emulsified Jatropha Oil to Diesel Engine Performances

    Kento Yokoi, Taiga Nakamura, Ryoichi Ota, Ichiro Asano, Tomohisa Dan

    International Symposium on Marine Engineering and Technology (ISMT2019 Busan), G04-03, 24 Oct. 2019, English, International conference

    Oral presentation

  • Fuel and Combustion Characteristics of DME/WPO Blend Fuels

    Kenta Kuwaoka, Yu Mihara, Kosuke Sugiura, Ichiro Asano, Tomohisa Dan

    International Symposium on Marine Engineering and Technology (ISMT2019 Busan), G04-02, 24 Oct. 2019, English, International conference

    Oral presentation

  • Combustion Characteristics and Toxicity Evaluation of Bio-gasoline in Outboard Spark Ignition Engine

    Kodai Nakano, Wataru Miyazaki, Ichiro Asano, Tomohisa Dan

    International Symposium on Marine Engineering and Technology (ISMT2019 Busan), G04-01, 24 Oct. 2019, English, International conference

    Oral presentation

  • ディーゼル機関からのススの変異原性と多環芳香族炭化水素の関係

    Kento Hayami, Akira Yoshida, Masashi Kusu, Go-ichi Kon, Hideo Okamura, Tomohisa Dan, Yoshinori Haga, Ryohei Nakatsubo, Senri Matsumura

    Proceedings of 89th Marine Engineering Conference, Oct. 2019, Japanese, Domestic conference

    Oral presentation

  • Proposal and development of ERS

    Hiromasa Ikawa, Takashi Miwa, Tomohisa Dan

    Proceedings of 89th Marine Engineering Conference, Oct. 2019, Japanese, Domestic conference

    Oral presentation

  • Effect of Droplet Diameter Distribution in Water Emulsified Jatropha Oil to Diesel Engine Peformances

    Taiga Nakamura, Kento Yokoi, Ryoichi Ota, Ichiro Asano, Tomohisa Dan

    Proceedings of 27th ILASS-Japan Symposium (Okayama) CD-ROM , A-113 , pp.1-5, Dec. 2018, Japanese, Domestic conference

    Oral presentation

  • Diesel Engine Performance with Mixed Fuel Consist of Wood Tar and Dimethyl Ether

    Takashi Suzuki, Yu Mihara, Kenta Kuwaoka, Tomoki Shirahama, Ichiro Asano, Tomohisa Dan

    Proceedings of 27th ILASS-Japan Symposium (Okayama) CD-ROM , B-221 , pp.1-5, Dec. 2018, Japanese, Domestic conference

    Oral presentation

  • Study on the abnormality diagnosis with listening rod (1st Report)

    Hiromasa Ikawa, Takashi Miwa, Tomohisa Dan

    Proceedings of the 88th Conference on Marine Engineering (Okayama) , pp.41-42, Oct. 2018, Japanese, Domestic conference

    Oral presentation

  • Utlilization of Crude Plant Oil

    Tomohisa DAN

    Proceedings of the 88th Conference on Marine Engineering (Okayama) , pp.263-266, Oct. 2018, Japanese, Domestic conference

    Nominated symposium

  • 舶用ディーゼル機関からのススの変異原性と多環芳香族炭化水素

    楠 将史, 吉田 明輝, 速水 健斗, 今 吾一, 岡村 秀雄, 段 智久, 羽賀 雄紀, 松村 千里

    第88回マリンエンジニアリング学術講演会講演論文集(岡山) , pp.51-52, Oct. 2018, Japanese, Domestic conference

    Oral presentation

  • Analysis of Organic Contamination in Ship Engine Soot

    Senri Matsumura, Yoshinori Haga, Ryosuke Yoshiori, Ryohei Nakatsubo, Go-ichi Kon, Hideo Okamura, Tomohisa Dan, Toshiki Tojo, Hitomi Hasegawa, Takashi Miyawaki, Takahiro Nishino, Takeshi Nakano

    Proceedings of 21st Symposium of JSWE (Shimane) , pp.157, Sep. 2018, Japanese, Domestic conference

  • Crude Plant Oil Usage as Engine Fuel

    Tomohisa Dan

    Proceedings of 62nd Special Fund Lectures, pp.1-7, 09 Mar. 2018, Japanese, The Japan Institute of Marine Engineering, Kobe, Hyogo, Domestic conference

    [Invited]

    Nominated symposium

  • A Basic Research on Engine Room Simulator Training Corresponding to Recent Trend in Marine Engines

    Keiji Sato, Tomohisa Dan

    2nd JMETS Research Presentation, 31 Jul. 2017, Japanese, JMETS MTC, 神戸第2地方合同庁舎 第1会議室, Domestic conference

    Oral presentation

  • Effect of Underwater Exhaust of Outboard Engine Fueled with Bio-gasoline

    Wataru Miyazaki, Toru Hayakawa, Hideo Okamura, Tomohisa Dan, Ichiro Asano

    Proceedings of the 87th Conference on Marine Engineering (Tokyo) , pp.89-90, No.209, 16 May 2017, Japanese, The Japan Institute of Marine Engineering, Tokyo University of Marine Science and Technology, Tokyo, Japan, Domestic conference

    Oral presentation

  • Effect of Mixing Ratio of Jatropha oil/Gas oil Blend to Combustion Characteristics

    Wataru Hiraoka, Hideki Tanaka, Tomohisa Dan, Ichiro Asano

    Proceedings of the 87th Conference on Marine Engineering (Tokyo) , pp.91-92, No.210, 16 May 2017, Japanese, The Japan Institute of Marine Engineering, Tokyo University of Marine Science and Technology, Tokyo, Japan, Domestic conference

    Oral presentation

  • Optimized Utilization of Plant Oil for Diesel Fuel

    Tomohisa Dan

    The 259th Meeting of Research Committee of Diesel Engine, 16 Feb. 2017, Japanese, The Japan Institute of Marine Engineering, Osaka citry, Japan, Domestic conference

    [Invited]

    Public discourse

  • Longtime Operation of Diesel Engine Fuelled by Plant oil and Gas oil Blend

    Tomohisa Dan, Ichiro Asano, Naoki Nishiguchi, Makoto Aranami, Koji Kanno

    Proceedings of the 86th Conference on Marine Engineering (Himeji), No.228, pp.149-150, 26 Oct. 2016, Japanese, The Japan Institute of Marine Engineering, Himeji city (The Himeji Chamber of Commerce and Industry), Hyogo pref., Japan, Domestic conference

    Oral presentation

  • Combustion Characteristics of Jatropha Blended Fuel with Multiple Injection

    Hideki Tanaka, Tomohisa Dan, Ichiro Asano

    Proceedungs of Joint Forum among Industry, Bank, School and Government 2015 P-1-05 p.65, 11 Nov. 2015, Japanese, Kobe City College of Technology, Kobe City, Domestic conference

    Poster presentation

  • Diesel Engine Combustion of Dimethyl Ether Blended Fuel added with Sulfur Component

    Tomohiko Nakamura, Takaaki Tanaka, Tomohisa Dan, Ichiro Asano

    Proceedings of Joint Forum among Industry, Bank, School and Goverment 2015 P-1-06 p.66, 11 Nov. 2015, Japanese, Kobe City College of Technology, Kobe City, Domestic conference

    Poster presentation

  • Combustion Analysis of Straight Jatropha Oil for Application to Diesel Engine

    Takahiro Nakamoto, Tomohisa Dan, Ichiro Asano

    Proceedings of Joint Forum among Industry, Bank, School and Goverment 2015 P-1-07 p.67, 11 Nov. 2015, Japanese, Kobe City College of Technology, Kobe City, Domestic conference

    Poster presentation

  • Combustion of Dimethyl Ether Blendeed Fuel with Sulfur Components in Diesel Engine

    Takaaki Tanaka, Tahahiro Hisashiba, Tomohisa Dan, Ichiro Asano

    Proceedings of Conference on Marine Engineering, pp.117-118, 27 Oct. 2015, Japanese, The Japan Institute on Marine Engieering, Toyama International Conference Center, Toyama city, Toyama pref., Domestic conference

    Oral presentation

  • Combustion Analysis of Raw Jatropha Oil for Diesel Engine Application

    Tomohisa Dan, Takahiro Nakamoto, Naoto Katayama, Ichiro Asano, Yasuyuki Kori, Kouji Kanno

    Proceedings of Conference on Mrine Engineering, 27 Oct. 2015, Japanese, The Japan Institute of Marine Engineering, Toyama International Conference Center, Domestic conference

    Oral presentation

  • Plame Structure of Low Temperature Plasma assited Combustion at Atmospheric Pressure

    Kenya Hirosawa, Hiroshi Akamatsu, Tomohisa Dan, Takamitsu Yoshimoto

    Proceedings of Conference on Marine Engineering, 27 Oct. 2015, Japanese, The Japan Institute on Marine Engineering, Toyama International Conference Center, Toyama city, Toyama pref., Domestic conference

  • Effects by Low Temperature Plasma Assited Combustion at Atmospheric Pressure

    Takamitsu Yoshimoto, Kenya Hirosawa, Hiroshi Akamatsu, Tomohisa Dan

    Proceedings of Conference on Marine Engineering, 27 Oct. 2015, Japanese, The Japan Institute of Marine Engineering, Toyama International Conference Center, Toyama city, Toyama pref., Domestic conference

    Oral presentation

  • RBS Analysis for ISF Components Contained in PM in Exhaust Gas of Diesel Engine

    Sho Nagai, Takaaki Tanaka, Akira Taniike, Tomohisa Dan, Yuichi Furuyama

    Proceeedings of 85th Conference on Marine Engineering, pp.9-10, 26 Oct. 2015, Japanese, The Japan Institute of Marine Engineering, Toyama International Conference Center, Toyama city, Toyama pref., Domestic conference

    Oral presentation

  • Improvement of Diesel Spray Characteristics by Liquefied Dimethyl Ether

    Kazuto Matsumoto, Tomohisa Dan, Ichiro Asano

    23rd Symposium (ILASS-Japan) on Atomization, Proceedings pp.94-98, 18 Dec. 2014, Japanese, ILASS-Japan, The Japan Institute of Energy, Hirosaki University (Hirosaki city), Domestic conference

    Oral presentation

  • Effect of Exhaust Gas from Diesel Engine Using Heavy Fuel Oils with Dimethyl Ether on Aquatic Species

    Yu Shinohara, Takashi Otani, Hisayo Okamoto, Tomohisa Dan, Satoshi Asaoka, Hideo Okamura

    84th Marine Engineering Conference, Proceedings, pp.155-156, 21 Nov. 2014, Japanese, The Japan Institute of Marine Engineering, Shimonoseki city, Kaikyo Messe Shimonoseki, Domestic conference

    Oral presentation

  • Application of Bunker oil / DME mixed Fuel to Pre-combustion Chamber Type Diesel Engine

    Tomohisa Dan, Katsuya Yoshida, Ichiro Asano

    84th Marine Engineering Conference, Proceedings, pp.83-84, 20 Nov. 2014, Japanese, The Japan Institute of Marine Engineering, Shimonoseki city, Kaikyo Messe Shimonoseki, Domestic conference

    Oral presentation

  • Combustion Analysis of Jatropha / Hydrogen Peroxide Emulsion Fuel in Diesel Engine

    Tomohisa Dan, Takayuki Yamamoto, Ichiro Asano

    84th Marine Engineering Conference, Proceedings, pp.81-82, 20 Nov. 2014, Japanese, The Japan Institute of Marine Engineering, Shimonoseki city, Kaikyo Messe Shimonoseki, Domestic conference

    Oral presentation

  • Ion Beam Analyses for Particulate Matter Exhausted from Diesel Engine by Using Marine Diesel Oil Adding Sulfur Component

    Sho Nagai, Takahiro Hisashiba, Akira Taniike, Tomohisa Dan, Yuichi Furuyama

    84th Marine Engineering Conference, Proceedings, pp.13-14, 19 Nov. 2014, Japanese, The Japan Institute of Marine Engineering, Shimonoski city, Kaikyo Messe Shimonoseki, Domestic conference

    Oral presentation

  • Characteristics Improvement of Ship Fuel by Dimethyl Ether

    DAN Tomohisa

    The 250th Dieesel Engine Research Committee, 07 Nov. 2014, Japanese, The Japan Institute of Marine Engineering, Yanmar Museum, Nagahama city, Shiga Pref., Domestic conference

    [Invited]

    Public discourse

  • Effect of Sulfur Component in Fuel for Diesel Combustion Characteristics Operated by DME Mixed Fuel

    Yasuhiro NISHIMURA, Tomohisa DAN, Ichiro ASANO

    83rd Marine Engineering Conference, Proceedings pp.175-176, Sep. 2013, Japanese, The Japane Institute of Marine Engineering, Shizuoka, Japan, Domestic conference

    Oral presentation

  • Mutagenicity of Diesel Exhaust Particulates from DME Blend Oil

    Hisayo OKAMOTO, Tomohisa DAN, Hideo OKAMURA

    83rd Marine Engineering Conference, Proceedings pp.107-108, Sep. 2013, Japanese, The Japan Institute of Marine Engineering, Shizuoka, Japan, Domestic conference

    Oral presentation

  • Diesel Combustion by Using of Liquefied Dimethyl Ether - Kinematic Vicosity Measurement and Engine Performance

    DAN Tomohisa

    247th Diesel Engine Research Committee, 11 Jul. 2013, Japanese, Japan Institute of Marine Engineering, Osaka, Domestic conference

    [Invited]

    Nominated symposium

  • Utilization of Liquefied Dimethyl Ether for Promoting Better Combustion in Ship Diesel Engine

    Tomohisa Dan

    2nd EAISS (EAISS2012), Proceedings pp.107-108, 21 Dec. 2012, English, Kobe Univ.&NKKK&Maritime Science Promotion Foundation, Kobe, Japan, International conference

    [Invited]

    Invited oral presentation

  • Investigation in Characteristics Change of Bunker C Oil by Blending Dimethyl Ether

    DAN Tomohisa, MIZUKURA Makoto, RYU Younghyun, ASANO Ichiro

    82th Conference on Marine Engineering, Proceedings pp.133-134, Sep. 2012, Japanese, The Japan Institute of Marine Engineering, Takamatsu, Japan, Domestic conference

    Oral presentation

  • Combustion Analysis of Jatropha Emulsified Fuel in Diesel Engine -Case of Single and Direct Injection

    OUE Masaki, NGUYEN Kim-Bao, DAN Tomohisa, ASANO Ichiro, HASHIMOTO Masataka

    82th Conference on Marine Engineering, Proceedings pp.57-58, Sep. 2012, Japanese, The Japane Institute of Marine Engineering, Takamastsu, Japan, Domestic conference

    Oral presentation

  • Toxic Substances Absorbed on Diesel Exhaust Particles from Jatropha Oil

    NAKAMURA Sayoka, ODA Erina, MATSUMOTO Saori, OKAMOTO Hisayo, DAN Tomohisa, OKAMURA Hideo

    82th Conference on Marine Engineering, Proceedings pp.59-60, Sep. 2012, Japanese, The Japane Institute of Marine Engineering, Takamatsu, Japan, Domestic conference

    Oral presentation

  • Nitrated polycyclic aromatic hydrocarbons absorbed on diesel exhaust particulates from jatropha oil

    OKAMOTO Hisayo, NAKAMURA Sayoka, MATSUMOTO Saori, DAN Tomohisa, OKAMURA Hideo

    82th Conference on Marine Engineering, Proceedings pp.61-62, Sep. 2012, Japanese, The Japane Institute of Marine Engineering, Takamatsu, Japan, Domestic conference

    Oral presentation

  • Probability of Characteristics Improvement by Dimethyl Ether in Crude Fuel Derived from Rubbles

    DAN Tomohisa

    Hyogo Alliance of Universities and Colleges for Innovation, 5th Technical Presentation of Designated Fields, Proceedings pp.35-46, Sep. 2012, Japanese, Hyogo Alliance of Universities and Colleges for Innovation, Kobe, Domestic conference

    [Invited]

    Nominated symposium

  • Reforming of Bunker C Oil by Using Dimethyl Ether (Viscosity Measurement of Blending Fuel Containing Volatile Component)

    Tomohisa DAN, Younghyun RYU, Makoto MIZUKURA, Ichiro ASANO

    JASNAOE Proceedings of 2012 Spring Conference, No.14, 2012S-OS5-9, pp.121-124, May 2012, Japanese, Japan Society of Naval Architects and Ocean Engineers, Kobe, Japan, Domestic conference

    Oral presentation

  • Kinematic Viscosity Measurement of DME and Bunker Oil Blended Fuel for Diesel Engine Application

    Tomohisa Dan, Younghyun Ryu, Makoto Mizukura, Ichiro Asano

    8th KSME-JSME Thermal and Fluid Engineering Conference (Incheon) Forum02, FR02-004, pp.1-3, Mar. 2012, English, Korea Society of Mechanical Engineers-Japan Society of Mechanical Engineers, Incheon, Korea, International conference

    Oral presentation

  • Next Generation Fuel for Diesel Engine Application

    Tomohisa Dan

    Bilateral Seminar between Kobe University and Shanghai Jiao Tong University on Engine R&D, Feb. 2012, English, Kobe University, Faculty of Maritime Sciences, Kobe, Domestic conference

    Nominated symposium

  • Environmental Safeguards with Using Alternative Fuel in Diesel Engine

    Tomohisa Dan

    5th PAAMES ISC Meeting and Forum "Green Maritime Engineering Innovations", Dec. 2011, English, Taiwan Society of Naval Architects and Marine Engineers, Taipei, Taiwan, International conference

    [Invited]

    Keynote oral presentation

  • Diesel Combustion of Water Emulsified Jatropha Curcas Oil

    Kosuke SHIKIMI, Tomohisa DAN, Ichiro ASANO

    JASNAOE, Conference Proceedings, No.12 2011S-OS1-8, pp.21-24, Nov. 2011, Japanese, Japan Society of Naval Architects and Ocean Engineers, Kobe, Japan, Domestic conference

    Oral presentation

  • Exhaust Emission Improvement in Diesel Engine by Using Alternative Fuels

    Tomohisa Dan

    Exchange Seminar on Research Topics - Additional Meeting of the World NAOE Forum -, Nov. 2011, English, Japan Society of Naval Architects and Ocean Engineers, Osaka, Japan, International conference

    [Invited]

    Nominated symposium

  • Diesel Engine Performance of DME-C Heavy Oil Mixed Fuel

    Tomohisa DAN, Makoto MIZUKURA, YoungHyun RYU, Ichiro ASANO

    JASNAOE, Conference Proceedings, No.12 2011S-OS1-8, pp.21-24, May 2011, Japanese, Japan Society of Naval Architects and Ocean Engineers, Fukuoka, Japan, Domestic conference

    Oral presentation

  • The Addition Effect of DME on Environmental Toxixity of Diesel Exhaust Particulates

    Takuya SAWAMOTO, Hideo OKAMURA, Hirotsugu FUJITA, Tomohisa DAN

    81st Conference on Marine Engineering Proceedings pp.49-50, May 2011, Japanese, The Japan Institute of Marine Engineering, Tokyo, Japan, Domestic conference

    Oral presentation

  • Combustion Analisys of Diesel Engine with DME Mixed Fuel

    DAN Tomohisa, ASANO Ichiro, OUCHI Ryota

    JASNAOE, Conference Proceedings, No.11 2010K-OS-8, pp.383-384, Nov. 2010, Japanese, Japan Society of Naval Architects and Ocean Engineers, Kobe, Japan, Domestic conference

    Oral presentation

  • Reforming of Bunker C Oil by DME in Diesel Engine

    DAN Tomohisa, Makoto MIZUKURA, Kazuya ISHIDA, YoungHyun RYU, Masataka HASHIMOTO, Ichiro ASANO

    80th Conference on Marine Engineering, Aug. 2010, Japanese, The Japan Institute of Marine Engineering, Niigata, Japan, Domestic conference

    Oral presentation

  • Combustion Analysis of Jatropha Oil in Direct Injectin Diesel Engine

    DAN Tomohisa, Shota TANAKA, Masataka HASHIMOTO, Ichiro ASANO

    80th Conference on Marine Engineering, Conference Proceedings, pp.127-128, Aug. 2010, Japanese, The Japan Institute of Marine Engineering, Niigata, Japan, Domestic conference

    Oral presentation

  • Research of Alternative Fuels in Diesel Engine - Dimethyl Ether, Biofuel -

    Tomohisa Dan

    237th Research Committee of Diesel Engine, Jul. 2010, Japanese, The Japan Institute of Marine Engineering, Osaka, Japan, Domestic conference

    Nominated symposium

  • Mutagenic evaluation of the ship diesel exhaust gas from marine diesel engine

    Takuya SAWAMOTO, Hideo OKAMURA, Hirotsugu FUJITA, Tomohisa DAN

    80th Conference on Marine Engineering Proceedings pp.55-56, May 2010, Japanese, The Japan Institute of Marine Engineering, Niigata, Japan, Domestic conference

    Oral presentation

  • Combustion Characteristics of Emulsified Jatropha Oil in Pre-combustion Chamber Type Diesel Engine

    MIYAWAKI Naoya, DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro

    79th Conference on Marine Engineering, Conference Proceedings, pp.7-8, Sep. 2009, Japanese, The Japan Institute of Marine Engineering, Hiroshima, Japan, Domestic conference

    Oral presentation

  • Combustion Analysis of DME Blended Fuel in Diesel Engine

    OHUE Takahiro, DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro

    79th Conference on Marine Engineering, Conference Proceedings, pp.45-46, Sep. 2009, Japanese, The Japan Institute of Marine Engineering, Hiroshima, Japan, Domestic conference

    Oral presentation

  • Combustion Analysis of Jatropha Oil in Diesel Engine

    DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro, OTANI Tomohito

    78th Conference on Marine Engineering, Conference Proceedings, pp.27-28, Sep. 2008, Japanese, The Japan Institute of Marine Engineering, Nagasaki, Japan, Domestic conference

    Oral presentation

  • Combustion Improvement of Diesel Fuel by DME - Spray Observation at Atmosphere

    DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro, SUZUKI Naoki

    78th Conference on Marine Engineering, Conference Proceedings, pp.25-26, Sep. 2008, Japanese, The Japan Institute of Marine Engineering, Nagasaki, Japan, Domestic conference

    Oral presentation

  • Application to Diesel Engine of Mixed Fuel Comprising DME and Marine Diesel Oil (3rd Report : Influence of Engine Speed)

    DAN Tomohisa, HASHIMOTO Masataka, SUZUKI Naoki, OKUMURA Teppei

    77th Technical Conference of Marine Engineering, Conference Proceedings, pp.25-26, Oct. 2007, Japanese, The Japan Institute of Marine Engineering, Kobe, Japan, Domestic conference

    Oral presentation

  • Application to Diesel Engine of Blended Fuel Comprising Palm Oil and Gas Oil

    DAN Tomohisa, HASHIMOTO Masataka, OTANI Tomohito

    77th Conference of Marine Engineering, Conference Proceedings, pp.91-92, Oct. 2007, Japanese, The Japan Institute of Marine Engineering, Kobe, Japan, Domestic conference

    Oral presentation

  • Combustion Analysis of Bunker Oil with Addition of Water in Diesel Engine

    DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro, MASUDA Shohei

    75th Conference on Marine Engineering, Conference Proceedings, pp.17-18, Oct. 2006, Japanese, The Japan Institute of Marine Engineering, Kobe, Japan, Domestic conference

    Oral presentation

  • Diesel Engine Performance by Using of Emulsified Waste Vegetable Oil

    DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro, KUNIKAWA Akira

    74th Conference on Marine Engineering, Conference Proccedings, pp.13-14, Oct. 2006, Japanese, The Japan Institute of Marine Engineering, Tokyo, Japan, Domestic conference

    Oral presentation

  • Combustion Improvement of Waste-Vegetable Oil by Mixture of DME in a Diesel Engine

    DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro, NAKAMURA Takuro

    73rd Conference on Marine Engineering, Conference Proceedings, pp.69-70, May 2005, Japanese, The Japan Institute of Marine Engineering, Tokyo, Japan, Domestic conference

    Oral presentation

  • Application to Diesel Engine of Mixed Fuel Comprising DME and A-Heavy Oil (2nd Report : Engine Performance with Mix Ratio)

    DAN Tomohisa, HASHIMOTO Masataka, ASANO Ichiro, NAKAMURA Takuro

    72nd Conference on Marine Engineering, Conference Proceedings, pp.91-92, Oct. 2004, Japanese, The Japan Institute of Marine Engineering, Kobe, Japan, Domestic conference

    Oral presentation

  • The Application of the Waste-Vegetable Oil as a Bio-Fuel in a High-Speed Diesel Engine

    MATSUZAKI Shiro, HASHIMOTO Masataka, DAN Tomohisa, ASANO Ichiro

    71st Conference on Marine Engineering, Conference Proccedings, pp.33-34, May 2004, Japanese, The Japan Institute of Marine Engineering, Tokyo, Japan, Domestic conference

    Oral presentation

  • Exhaust Emission of Gas Turbine of Waste-Vegetable Oil Mixed Fuel (2)

    HASHIMOTO Masataka, DAN Tomohisa, ASANO Ichiro, KO Ri

    68th Conference on Marine Engineering, Conference Proceedings, pp.125-128, Nov. 2002, Japanese, The Japan Institute of Marine Engineering, Kobe, Japan, Domestic conference

    Oral presentation

  • Utilization of Waste-Vegetable Oil in High-Speed Diesel Engine

    HASHIMOTO Masataka, DAN Tomohisa, ASANO Ichiro, KUBO Takashi

    68th Conference on Marine Engineering, Conference Proceedings, pp.117-120, Nov. 2002, Japanese, The Japan Institute of Marine Engineering, Kobe, Japan, Domestic conference

    Oral presentation

  • Combustion Improvement of Waste-Vegetable Oil Added Fuel in Gas Turbine

    HASHIMOTO Masataka, DAN Tomohisa, ASANO Ichiro, OH Teppu

    66th Conference on Marine Engineering, Conference Proceedings, pp.29-32, Oct. 2001, Japanese, The Japan Institute of Marine Engineering, Kobe, Japan, Domestic conference

    Oral presentation

  • Combustion Analysis of Mixed Fuel Droplet by Laser Speckle Method

    HASHIMOTO Masataka, DAN Tomohisa, ASANO Ichiro, CHO Shinyo

    66th Conference on Marine Engineering, Conference Proceedings, pp.13-16, Oct. 2001, Japanese, The Japan Institute of Marine Engineering, Kobe, Japan, Domestic conference

    Oral presentation

  • Modeling of Turbulent Primary Breakup in Diesel Spray

    Tomohisa Dan, Ming-Chia Lai

    11th Annual Conference on Liquid Atomization and Spray Systems, ILASS-Americas ’98, pp.48-52, May 1998, English, ILASS-Americas, Sacramento USA, International conference

    Oral presentation

  • Analysis of Flow Field in Diesel Fuel Sprays by Particle-image Velocimetry

    Tomohiro Takahashi, Tomohisa Dan, Sayo Takagishi, Jiro Senda, Hajime Fujimoto

    14th Symposium on Internal Combustion Engines, Sep. 1997, Japanese, JSME&JSAE, Nagoya, Japan, Domestic conference

    Oral presentation

  • Numerical Analysis of Free Diesel Spray

    Tomohisa Dan, Sayo Takagishi, Tomoyuki Kanda, Jiro Senda, Hajime Fujimoto

    74th Annual Conference of Japan Socisty of Mechanical Engineers Proceedings pp.561-562, Oct. 1996, Japanese, JSME, Kyoto, Japan, Domestic conference

    Oral presentation

  • Structure and Formation of Diesel Fuel Spray

    Hajime Fujimoto, Tomohisa Dan

    ILASS-Korea Annual Meeting ’96, pp.3-15, Oct. 1996, English, Institute of Liquid Atomization and Spray Systems-Korea, Korea, International conference

    [Invited]

    Keynote oral presentation

  • Modeling of Non-evaporating Free Diesel Spray

    Tomohisa Dan, Sayo Takagishi, Jiro Senda, Hajime Fujimoto

    71st General Assembly Meeting of JSME Kansai Branch, Proceedings No.964-1, pp.120-121, Mar. 1996, Japanese, JSME, Osaka, Japan, Domestic conference

    Oral presentation

  • Spray Characteristics of High-Pressure Diesel Spray

    Hajime Fujimoto, Tomohisa Dan, Sayo Takagishi, Jiro Senda

    Institute of Liquid Atomization and Spray Systems-Korea, Proceedings of ILASS-Korea, Annual Meeting ’95, pp.126-131, Oct. 1995, English, ILASS-Korea, Korea, International conference

    Oral presentation

  • Spray Characteristics of High-injection Pressure Diesel Fuel Spray

    Sayo Takagishi, Tomohisa Dan, Jiro Senda, Hajime Fujimoto

    12th Symposium on Internal Combustion Engines, Jul. 1995, English, JSME&JSAE, Omiya, Japan, International conference

    Oral presentation

  • Effect of Ambient Conditions on Diesel Spray Structure

    Ohishi Naoki, Tomohisa Dan, Jiro Senda

    72nd Annual Meeting of JSME, Procceidngs of 3, pp.174-176, Aug. 1994, Japanese, JSME, Sapporo, Japan, Domestic conference

    Oral presentation

  • Atomization Mechanism in Diesel Spray

    Ohishi Naoki, Tomohisa Dan, Jiro Senda

    11th Internal Combustion Engine Conference, Jul. 1993, Japanese, JSME&JSAE, Tokyo, Japan, Domestic conference

    Oral presentation

  • Spray Characteristics of Gas Dissolved in Diesel Injection

    Jiro Senda, Ichiro Shibata, Tomohisa Dan, Hajime Fujimoto

    1st Conference of Liquid Atomozation and Spray Systems, Dec. 1992, Japanese, ILASS-Japan, Yokohama, Japan, Domestic conference

    Oral presentation

  • A Study on the Structure of Diesel Spray (Effect of Needle Lift Control)

    Tomohisa Dan, Shinsuke Kimura, Tsutomu Nomura, Jiro Senda, Hajime Fujimoto

    251st Conference of JSME Kansai Branch, Proceedings No.924-5, pp.130-132, Nov. 1992, Japanese, JSME, Osaka, Japan, Domestic conference

    Oral presentation

  • A Study on the Structure of Diesel Spray (Behavior of Steady Sprays in the Vicinty of the Nozzle Hole)

    Tomohisa Dan, Jiro Senda, Hajime Fujimoto

    19th Conference of Liquid Atomization and Spray Systems in Japan, Conference Proceedings (1992), pp.41-46, Aug. 1992, Japanese, The Japan Institute of Energy, Tokyo, Japan, Domestic conference

    Oral presentation

Association Memberships

  • THE JAPAN INSTITUTE OF ENERGY

  • The Japan Society of Naval Architects and Ocean Engineers

  • Institute for Liquid Atomization and Spray Systems-Japan

  • SAE International

  • Society of Automotive Engineers of Japan

  • The Japan Society of Mechanical Engineers

  • The Japan Institue of Marine Engineering

Research Projects

  • Advanced application of low-temperature plasma for reduction of environmental impact in heat engines

    Tomohisa Dan, Hiroshi Akamatsu

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), Kobe University, 01 Apr. 2020 - 31 Mar. 2023

    研究開始時の研究の概要 地球温暖化の要因となるGHG(CO2、CH4など)を排出する熱機関において、それらの排出量を低減させることが環境保全の観点からも必要である。その手法として、燃料燃焼を促進させる効果のあるプラズマを熱機関の燃焼室内部で生成させて作用させることを試みる。レトロフィットで試作するガス燃料を利用する二元燃料エンジンシステムを用いて、プラズマのガス燃焼促進効果を検証して、本手法の有効性を明らかにする。

  • DAN Tomohisa

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kobe University, 01 Apr. 2017 - 31 Mar. 2020, Principal investigator

    This study aims to clarify the effect of blending of liquefied DME to enhance the combustion state of high viscosity materials, such as Wood Tar or Marine Fuel Oils. In case of Wood Tar, it was obtained that a short period operation with a diesel engine was able, but the engine has stopped due to small contamination in Wood Tar. Also, a system which mixes two liquid materials and supplies continuously to engine was established in this study. Liquid-Liquid mixing test was carried out, and performance was confirmed. However, mixing with volatile materials is remained. It would be further objectives from this study.

    Competitive research funding

  • IKEA HIROMASA

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), Kobe University, 01 Apr. 2016 - 31 Mar. 2019

    This study relates to utilization of the advanced sensory marine engine room simulator for the purpose of realizing the improvement in ability for engineers to discovery early trouble. First, we measured vibration and sound of normal or abnormal bearing through the listening-rod to develop the imitation listening rod and analyzed them. And we found out the damage frequency at the abnormal bearing which isn't seen could be confirmed. Next, we manufactured the imitation listening rod using the oscillator for the bone conduction earphone of the marketing. A similar analysis using this indicate that amplitude of vibration and sound is smaller and some signal don’t have the damage frequency. In parallel, we added functions to existing engine room simulator, for above obtained vibrations driving an imitation listening rod.

    Competitive research funding

  • IKAWA Hiromasa, UCHIDA Makoto, DAN Tomohisa, MIWA Takashi, MAWAI Kazuya

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), Kobe University, 01 Apr. 2013 - 31 Mar. 2016

    This study relates to the utilization of the sensory engine room simulator for the purpose of realizing the improvement in ability for engineers to discovery early troubles. At first, we investigated the method and system for education using engine room simulator by the five senses in particular in the inside and outside the country. Then we made the experimental device which can control the surface temperature of the imitation pipe, and confirmed, in study on the measurement of pipe temperature by hand touching with this device, that the thermometry accuracy was affected by the experience as the marine engineer, and that training improved this accuracy. Moreover we have developed the sensory engine room simulator incorporating the imitation pipe equipment with Marine Engineer Plant Simulator (MEPS) in Kobe University.

    Competitive research funding

  • OKAMURA Hideo, HARINO Hiroya, DAN Tomohisa, ASAOKA Satoshi

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research, Grant-in-Aid for Challenging Exploratory Research, Kobe University, 01 Apr. 2013 - 31 Mar. 2015

    The seawater bubbled with exhaust gas emitted from marine diesel engine using a future-generation fuel (new fuel), a 70 % heavy fuel oil with 30% dimethylether, or a traditional heavy fuel oil (C fuel oil) was subjected for ecotoxicity assay and chemical analyses. The seawater bubbled with the gas using C fuel oil indicated higher toxicity on algal growth than that using new fuel. Toxic substances to inhibit algal growth were adsorbed on the particles whose diameter ranging from 0.1 to 1 μm in the seawater. The total amount of polycyclic aromatic hydrocarbons (PAHs) adsorbed on the particles in the seawater bubbled with the gas using new fuel was higher than that using C fuel oil. Carcinogenic PAHs were adsorbed on the particles whose diameter ranging from 0.1 to 1 μm in the seawater bubbled with the gas using C fuel oil, but they were not detected in the seawater with the gas using future-generation fuel.

    Competitive research funding

  • Establishment in Disposal of Rubbles Consists of Woods, and Extracting Recycle Energy with Combustion Process

    Tomohisa Dan

    Hyogo Alliance of Universities and Colleges for Innovation, Grat-in-Aid for Research Innovation, Apr. 2011 - Feb. 2013, Principal investigator

    自然災害で発生する倒壊家屋等の瓦礫材の処理は地域復興における重要な課題である。沿岸部に埋立地がない場合には瓦礫材は主に焼却処理されるが、それらを有効に利用することが考えられる。本研究会は道路舗装等のアスファルトプラントの燃焼炉(キルン)を活用した瓦礫材の処理および再生エネルギーの抽出(バイオマスガス・木タール等)と有効利用の技術を検討する。これにより災害復興や廃棄木材の処理等のための将来技術システムの創出を目指す。

    Competitive research funding

  • DAN Tomohisa

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), Kobe University, 2011 - 2013

    This project aims to improve the characteristics of residual fuel, which is mainly used for ship engines, as well as the exhaust emissions by mixing a liquefied Dimethyl Ether (DME). During the first research year, a measurement system of kinematic viscosity was established to measure the volatile mixed fuels which contained the liquefied DME. From the experiments, it was obtained that the kinematic viscosity of mixing fuels drastically decreased with mixing DME in an exponential function. In the last research years, the mixing system of DME to residual fuel was made to adopt engine running tests. From the tests, it was concluded that the imperfect burning fractions, such as CO, HC, and PM, could be reduced by mixing DME. And within a certain condition, the thermal efficiency of the engines could be improved by the DME mixing.

  • 輸送の三原則を統合した国際海上輸送システム創出の研究

    塩谷 茂明

    文部科学省, 特別研究推進, Apr. 2008 - Mar. 2012

    Competitive research funding

  • OKAMURA Hideo, DAN Tomohisa, FUJITA Hirotugu, OKAMOTO Hisayo, SAWAMOTO Takuya, MIZUNO Rui, MATSUMOTO Saori

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research, Grant-in-Aid for Challenging Exploratory Research, Kobe University, 2010 - 2012

    Environmental hazard of the particulate matters (PM) in ship exhaust gas emitted with next generation fuels was evaluated using chemical analyses and ecotoxicity testing. The PM emission, the ecotoxicity, and the mutagenicity of the PM generated from Jatropha oil were lower than the ones from marine diesel oil (MDO: heavy oil A) and heavy fuel oil (HFO: heavy oil C). The PM emission and the ecotoxicity/mutagenicity of the PM generated from the 70 % heavy oils mixed with 30 % dimethyl ether (DME) did not quantitatively decreased in comparison with the ones from MDO or HFO. New compounds produced from heavy oils and DME might explain non-reduction in the toxicity.

  • OKAMURA Hideo, DAN Tomohisa, FUJITA Hirotsugu

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kobe University, 2008 - 2011

    Biomonitoring procedure using some environmental organisms was applied to assess pollution of port sediments collected at high maritime activity. Some sediments were very toxic to marine photobacteria, which could respond according to the quality of the port sediments. It was, however, difficult to ascertain the observed toxicity with residues of some antifouling compounds and polycyclic aromatic hydrocarbons in the toxic sediments. It was suggested that a wide variety of toxic compounds existed in port sediments.

  • 船舶排ガス由来粒子状物質が海洋環境に及ぼす影響と制御に関する研究

    岡村 秀雄, 藤田 浩嗣, 段 智久

    日本学術振興会, 科学研究費助成事業 挑戦的萌芽研究, 挑戦的萌芽研究, 神戸大学, 2008 - 2009

    1.船舶排ガス由来粒子状物質(SDEP)中の多環芳香族炭化水素(PAH)およびニトロ化PAH(NPAH)の定量 フォークリフトディーゼルエンジン由来の粒子状物質(標準試料:SRM2975)を供試し、ジクロロメタンを抽出溶媒として高速溶媒抽出装置を用いて有機溶媒可溶画分(SOF)を調製し、アミノプロピルカラムおよびアミノプロピルHPLCカラムを用いた2段階処理の後、15種類のPAHおよび11種類のNPAHをそれぞれ定量する分析方法を確立した。標準試料の他に、(1)A重油を燃料とした本学部練習船の煙突付着スス、(2)C重油を燃料とした実験エンジンIの冷却器内部付着スス、(3)A重油を燃料とした実験用エンジンIIからのSDEP、(4)植物油を燃料とした実験用エンジンIIからのSDEPを供試した。総PAH量が多かったのは、(3)>(4)=(2)>(1)の順であった。分析対象としたNPAHの中で検出されたのは1-nitropyreneのみであり、量が多かった順に(2)>(1)>(4)>(3)であった。 2.SDEPが海洋生態系に及ぼす影響および化学的・毒性学的特性の評価 海産発光細菌に対して、4種類のSOFの中で(1)のみが有意な阻害を示した。一方、Salmonella typhimurium NM2009株を用いた変異原性試験では、試料(1)と(2)が直接変異原性を示し、(2)は間接変異原性も示した。変異原性を示した試料(2)、および(2)から調製したSOFにそれぞれ紫外線UV-Cを8時間照射した。SOFに紫外線を照射して8時間後には全PAHの99.9%が分解したが、変異原性に顕著な減少は認められず、また発光細菌への阻害は逆に強まった。スス粒子そのものに同じ強度の紫外線を8時間照射しても、PHA量、変異原性に顕著な減少は認められなかった。以上のことから、紫外線照射によってSDEPに付着する有機有害成分の生物活性を消去することは困難であると推測された。

  • Improvement of Exhaust Gas Emission in Marine Diesel Engine by Blending DME

    DAN Tomohisa

    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), Kobe University, 2006 - 2007, Principal investigator

    In this study, the reduction of harmful exhaust emissions was investigated by use of blending Dimethyl Ether to conventional fuels in a diesel engine. DME is one of chemical compounds those are ignitable as easily as conventional gas oil. Moreover, it contains Oxygen and has no direct carbon bond. Thus, it emits no soot in the combustion flame. So, it is useful as the alternative fuel of diesel engines. On the other hand, its lubricity is very low and it corrodes the rubber materials. In the experiment of this study, DME has been blended with the marine diesel oil in order to improve the lubricity. The high-pressure vessel was used as the fuel tank, and fuel lines were replaced with Teflon tubes. With those modifications in the fuel supplying line, DME was able to be used as the liquefied sate. The direct injection type of diesel engine was modified to access the measurement of cylinder pressure history. The spacing ring was inserted between the cylinder block and the cylinder head. The pressure sensor was mounted to the ring and the pressure was measured. In the experiment, the time history of cylinder pressure was used to calculate the heat release rate. From the calculated rate, the combustion regions were defined in order to evaluate the change in combustion phenomena. From the experiment study, the following results are drawn. 1) NOx emissions could be reduced by blending DME. 2) Soot emissions could be reduced by blending DME. Those trends were seen in all engine speeds and engine load conditions. In the experimental condition range, the mixing rate of 40% DME was the best condition to reduce the exhaust emission in the diesel engine. It is concluded that DME is useful to reduce the harmful exhaust emission in the diesel engine.

    Competitive research funding

  • Application of Used Edible Oil/Dimethyl Ether Blended Fuel for Diesel Engine

    Tomohisa Dan

    NIKKO Memorial Foundation, Grant in aid for Research, Apr. 2004 - Mar. 2005, Principal investigator

    Competitive research funding

  • Application of Dimethyl Ether Fuel for Diesel Engine

    Tomohisa Dan

    Japan Society for the Promotion of Science, Grant-in-Aid for Young Scientists (B), 若手研究(B), 神戸商船大学->神戸大学(海事科学部), 2002 - 2003, Principal investigator

    本研究では,幅広い分野で使用されているディーゼル機関め代替燃料として,ジメチルエーテル(DME)を用いることを検討した.DMEの燃料としての利点という観点では,LPG同様,数気圧の加圧で液化するため運搬方法が簡素化できること,自己着火性の指標であるセタン価が55〜60と高いためにディーゼル機関に適していること,また分子構造として炭素同士の結合がないことから燃焼時にすすがほとんど発生しないこと等の利点がある.その一方で,潤滑性がほとんどないため,燃料噴射ノズルの内部や燃料噴射ポンプのプランジャなどにスカッフィングを引き起こすなどの欠点がある. 本実験では潤滑性を補うために,DMEにA重油を混合して,この混合燃料をディーゼル機関で燃焼させることを試みた.供試機関には横型水冷4サイクル単気筒直接噴射式ディーゼル機関(ボア92mm×ストローク96mm)を使用した.実験条件として,機関回転数は2000rpm一定とし,負荷は5段階(0,16,33,49,65%)に設定して燃焼圧力,排気ガス成分などの機関性能の測定を行った,また燃料噴霧の発達状況を可視化するために,大気圧下に燃料を噴射して高速度ビデオカメラにより撮影をした.DMEとA重油の混合率は,重量割合でDME25%A重油75%,DME50%A重油50%の2種類を試験し,比較のためにA重油100%,軽油100%の運転も行った. 実験より次の知見を得た.(1)加圧下ではDMEとA重油との混合性は良好で,長期間保存しても分離しない.(2)DME・A重油混合燃料の噴霧特性としては,A重油を混合したことにより大幅な噴霧到達距離の減少が起きることなく適度な噴霧角を得られる.(3)DMEを混合すると着火遅れ期間を小さくさせる効果がある.(4)DME・A重油混合燃料を用いた場合,わずかではあるがCO2の削減効果があり,スモークに関しては大幅な削減ができる.(5)DMEとA重油の混合割合は排ガス特性,機関運転性能などを考慮した結果,50%:50%が適している.また,数値計算では,DMEの諸物性をKIVA2コードに適用し,噴霧の分散に関して計算を行った.その結果,実験で得られたような噴霧角の増大の傾向が計算でも再現された. 以上の研究結果より,DMEをディーゼル機関に適用する場合,潤滑性を補うためにA重油と混合するのは有効であると結論した.

    Competitive research funding

  • ディーゼル噴霧構造の形成過程・微粒化機構の実験的および解析的研究

    段 智久

    日本学術振興会, 科学研究費助成事業 特別研究員奨励費, 特別研究員奨励費, 同志社大学, 1998 - 1999

Academic Contribution

  • Peer reviewer of Academic Journals

    Peer reviewer of Academic Journals

    Elsevier (Energy, Fuel and so on)

    2014 - Present

    Peer review etc

  • Contribution to International Meeting (PAAMES)

    Contribution to International Meeting (PAAMES)

    PAAMES

    01 Apr. 2006 - Present

    Academic society etc