2023/05/28 更新

写真a

ソク ラトナック
ソク ラトナック
Scopus 論文情報  
論文数: 34  Citation: 151  h-index: 8

Click to view the Scopus page. The data was downloaded from Scopus API in May 27, 2023, via http://api.elsevier.com and http://www.scopus.com .

所属
研究院(研究機関) 次世代自動車研究機構
職名
主任研究員(研究院准教授)
学位
2015年 Waseda University Dr. Eng.
2011年 Institut Teknologi Bandung MSME (cum laude)
2009年 Institute de Technologie du Cambodge Diplôme d'Ingénieur, 1st class honor
2006年 Institut de Technologie du Cambodge Diplôme Universitaire de Technologie, 1st class honor
メールアドレス
メールアドレス
プロフィール

1. Editorial board members (AE): 

      - SAE Int. J. of Electrified Vehicles

      - SAE Int. J. of Commercial Vehicles

      - SAE Int. J. of Sustainable Transportation, Energy, Environment, & Policy

2. Associate Chair: 15th Int ACM Automotive User Interfaces & Veh. Applications, Sep 18-21, 2023, Ingolstadt , Germany

3. Program Committee, 2022 IEEE Int. Conference on AI in Engineering and Technology, Sep 13-15, 2022, Malaysia

4. Guest Associate Editor / Review Editor: Frontiers in Future Transportation 

5. Advisory Panel Member of multiple MDPI Journals: Vehicles, Future Transportation, Electrochemistry, Clean Technologies, Applied Sciences, Fire, Pollutants, Sustainability, Atmosphere ... 

6. Event Committee, The 2nd International Electronic Conference on Processes: Process Engineering—Current State and Future Trends, May 17-31, 2023

7. Reviewers: 20+ Journals & Conferences: Elsevier, SAE, IEEE, ASME, SAGE, MDPI, Springer, Taylor&Francis

経歴

  • 2020年
    -
    継続中

    早稲田大学   研究院准教授 (w/ 草鹿 仁 教授)

  • 2018年
    -
    2020年

    早稲田大学   研究院講師 (w/ 草鹿 仁 教授)

  • 2016年
    -
    2017年

    スズキ自動車会社   エンジニア

  • 2015年
    -
    2016年

    早稲田大学   RA

  • 2012年
    -
    2015年

    早稲田大学   TA

  • 2012年08月
     
     

    京都大学   客員研究員 (w/ 塩路 昌弘 教授)

  • 2012年07月
     
     

    北海道大学   客員研究員 (w/ 近久 武美 教授)

  • 2011年
    -
    2012年

    National Polytechnic Institute of Cambodia   Part-time lecturer

  • 2011年
    -
    2012年

    Institut de Technologie du Cambodge   Mechanical Engineering   Full-time Lecturer/Assistant Researcher

▼全件表示

学歴

  • 2012年
    -
    2015年

    早稲田大学   工学博士(指導教員:草鹿 仁 , 大聖 泰弘)  

  • 2009年
    -
    2011年

    Institut Teknologi Bandung   MSME (with Distinction)  

    Supervisors: Iman K Reksowardojo, Wiranto Arimunandar, Tirto Prakoso, Toshio Shudo

  • 2006年
    -
    2009年

    Institut de Technologie du Cambodge   Génie Mécanique   Diplôme d'Ingénieur (1st class honor degree)  

  • 2003年
    -
    2006年

    Institut de Technologie du Cambodge   Génie Mécanique   Diplôme Universitaire de Technologie (1st class honor degree)  

委員歴

  • 2023年04月
    -
    継続中

    SAE International Journal of Sustainable Transportation, Energy, Environment, & Policy

  • 2022年
    -
    継続中

    SAE International  SAE International Journal of Electrified Vehicles

  • 2022年
    -
    継続中

    SAE International  SAE International Journal of Commercial Vehicles

所属学協会

  • 2021年
    -
    継続中

    IEEE Intelligent Transportation Systems Society

  • 2021年
    -
    継続中

    IEEE Vehicular Technology Society

  • 2021年
    -
    継続中

    Institute of Electrical and Electronics Engineers (IEEE)

  • 2018年
    -
    継続中

    自動車技術会

  • 2014年
    -
    継続中

    The American Society of Mechanical Engineers

  • 2014年
    -
    継続中

    SAE International

▼全件表示

研究分野

  • 熱工学   Electrified Vehicles ; CFD; Internal Combustion Engines

研究キーワード

  • Vehicle thermal management

  • Electrified transportation

  • Thermoelectric waste heat recovery

  • Computational Fluid Dynamics

  • Internal combustion engine

受賞

  • Waseda Asia Special Fellowship for PhD Student (Full for 2012-2015)

    2012年09月   Waseda University;  

  • JICA Fellowship for Guest Research Associate at Kyoto University

    2012年08月  

  • JICA Fellowship for Visiting Researcher at Hokkaido University

    2012年07月  

  • JICA Fellowship for Grad. Student (Full for 2009-2011)

    2009年09月  

  • 1st class honor degree for Diplôme d'Ingénieur

    2009年07月   Institut de Technologie du Cambodge;  

  • Youth Energy Representative to Asian Youth Energy Summit @NUS, Singapore

    2008年08月   Ministry of Education, Youth and Sports  

  • 1st class honor degree for Diplôme Universitaire de Technologie

    2006年07月   Institut de Technologie du Cambodge;  

  • University-Merit-Based Scholarship

    2004年   Institut de Technologie du Cambodge;  

  • SUMITOMO and ACATEL Fellowship for 1st Class Degree Student 2004-2009 (for 5 consecutive years)

    2004年  

▼全件表示

 

論文

  • Development and validation of thermal performances in a novel thermoelectric generator model for automotive waste heat recovery systems

    Ratnak Sok, Jin Kusaka

    International Journal of Heat and Mass Transfer   202   123718 - 123718  2023年03月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • A novel laminar flame speed equation for quasi-dimensional combustion model refinement in advanced, ultra-lean gasoline spark-ignited engines

    Ratnak Sok, Hidefumi Kataoka, Jin Kusaka, Akira Miyoshi, Rolf D. Reitz

    Fuel   333   126508 - 126508  2023年02月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

    Scopus

  • Thermoelectric Generation from Exhaust Heat in Electrified Natural Gas Trucks: Modeling and Analysis of an Integrated Engine System Performance Improvement

    Ratnak Sok, Jin Kusaka, Hisaharu Nakashima, Hidetaka Minagata, Pavlos Dimitriou, Jinlong Liu

    Journal of Energy Resources Technology     1 - 19  2023年01月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    Abstract

    Using thermoelectric generators (TEG) to reduce exhaust heat loss from internal combustion engines can improve emissions and the fuel economy of conventional and electrified vehicles. However, TEG potentials have not been investigated in hybridized, compressed natural gas (CNG), twin-turbocharged, spark-ignited (SI) engines. This work demonstrates TEG's effectiveness in boosting a hybridized 3.0 L CNG engine using model-based development. TEG experiments are performed to measure thermal performances under different inlet gas conditions for model validations. Simplified user-defined functions of flow friction and heat transfer coefficients are used to calibrate the model. A fast-calibration model can reproduce measured heat transfer, pressure drop, and thermal performances. The engine performances are validated against measured 35 steady-state conditions from the production engine used in light-duty CNG trucks under the JE05 drive cycle. Next, the model is connected to the turbocharging system downstream of the well-calibrated 4-cylinder SI engine model. Under the peak performance condition (peak brake thermal efficiency BTE at 2400 RPM and 102 kW load), the results show that the engine BTE is improved by 0.56% using a 7×9 TEG module arrangement (3-sheet TEG with 1.5× A4 size). A 9×10 arrangement can enhance the BTE to 0.8%. Effective electrical power is generated up to 1.168 kW from the TEG, depending on the JE05 operating regions, without significant brake power loss.

    DOI

  • Experimental and modeling analysis on thermoelectric heat recovery to maximize the performance of next-generation diesel engines dedicated for future electrified powertrains

    Ratnak Sok, Jin Kusaka

    Applied Thermal Engineering   219   119530 - 119530  2023年01月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

    Scopus

    2
    被引用数
    (Scopus)
  • Development and Comparison of Virtual Sensors Constructed using AI Techniques to Estimate the Performances of IC Engines

    Arravind Jeyamoorthy, Takuma Degawa, Ratnak Sok, Toshikado Akimichi, Shigeaki Kurita, Masatoshi Ogawa, Takayuki Takei, Ikuta Hayashi, Jin Kusaka, Beini Zhou, Kyohei Yamaguchi, Iku Tanabe

    SAE Technical Paper Series    2022年12月  [査読有り]

    担当区分:責任著者

    DOI

    Scopus

  • Modeling analysis on combined effects of VVT/VCR engine technology to reduce fuel consumption of light-duty parallel hybrid CNG trucks

    Ratnak Sok, Jin Kusaka, Hisaharu Nakashima, Hidetaka Minagata

    ASME Technical Paper    2022年11月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

    Scopus

  • Thermoelectric generation from exhaust heat in electrified natural gas trucks - part 1: modeling and baseline analysis on engine system efficiency improvement

    Ratnak Sok, Jin Kusaka, Hisaharu Nakashima, Hidetaka Minagata

    ASME Technical Paper    2022年11月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

    Scopus

  • Thermoelectric Exhaust Heat Recovery to Maximize Brake Thermal Efficiency of Advanced Diesel Engines: Modeling and Baseline Analysis

    Ratnak Sok, Jin Kusaka

    ASME 2022 ICE Forward Conference    2022年10月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    Abstract

    This work demonstrates the enhancement of brake thermal efficiency (BTE) of an advanced, turbocharged, production-intent 2.2 L diesel engine with a thermoelectric waste heat recovery system (TEG-WHR). The integrated engine model with the TEG is developed using 0D/1D software. Experimental data from the corrugated fin TEG under fin pitch = 1.0–2.0 mm, inlet gas temperatures (200–300 °C), and mass flow rates (5.0–15.0 g/s) are used for validating the model. The TEG model can reproduce measured pressure drop, heat transfer, and thermal performance characteristics. A 1-cylinder engine model parented from the advanced turbocharged diesel engine is developed. Under motoring and firing conditions, measured exhaust pressure, temperature, velocity, mass flow rate, and enthalpy are validated under various valve timings. Finally, the 3-layer TEG model is connected to the 4-cylinder engine to maximize its performance under a highly efficient (peak BTE) operating condition at 2250 RPM. Optimal size and thermoelectric module arrangement of the TEG system in the engine system considering a tradeoff between the TEG generated electrical power and engine pumping losses are suggested. The effective power of 1.1 kW and 1.1 % BTE improvement are obtained from the 3-sheet TEG system. As a result, a 49.9 % engine BTE is demonstrated without brake power loss.

    DOI

  • Waste Heat Recovery via Thermoelectric Generation in a Natural Gas Engine: Numerical Modeling and Baseline Analysis

    Ratnak Sok, Jin Kusaka, Hisaharu Nakashima, Hidetaka Minagata

    Proceeding of 7th Thermal and Fluids Engineering Conference (TFEC)    2022年05月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

  • Fuel-reforming effects on a gasoline direct injection engine under a low-temperature combustion mode: Experimental and kinetics analyses

    Ratnak Sok, Jin Kusaka

    Energy Conversion and Management   255   115304 - 115304  2022年03月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

    Scopus

    5
    被引用数
    (Scopus)
  • Machine Learning Application to Predict Combustion Phase of a Direct Injection Spark Ignition Engine

    Rio Asakawa, Keisuke Yokota, Iku Tanabe, Kyohei Yamaguchi, Ratnak Sok, Hiroyuki Ishii, Jin Kusaka

    International Journal of Automotive Technology   23 ( 1 ) 265 - 272  2022年02月  [査読有り]

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • Predicting Unburned Hydrocarbons in the Thermal Boundary Layer Close to the Combustion-chamber Wall in a Gasoline Engine Using a 1-D Model

    Kei Yoshimura, Hajime Yahata, Shoya Tanamachi, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka, Satoshi Tokuhara

    International Journal of Automotive Technology   23 ( 1 ) 233 - 242  2022年02月  [査読有り]

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • Effects of Partial Oxidation and Octane Sensitivity on Flame Stretch Rate at Extinction under EGR Conditions

    Kei Yoshimura, Kohei Isobe, Satoshi Tokuhara, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka

    The Proceedings of the International symposium on diagnostics and modeling of combustion in internal combustion engines   2022.10   A5 - 3  2022年

    DOI

  • Experimental Investigation on the Effects of Direct Fuel Injection Into Low-O2 Recompression Interval of an HCCI Engine

    Ratnak Sok, Jin Kusaka

    ASME Technical Paper    2021年11月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    <title>Abstract</title>
    Gasoline direct injection (GDI) and negative valve overlap (NVO) are standard strategies to control combustion characteristics and exhaust gas emissions in homogenous charge compression ignition (HCCI) engines. In this work, experimental data from a single-cylinder engine operated under the GDI-HCCI mode were analyzed. The experiments were performed at an equivalence ratio of 0.95 under a mid-load condition. A side-mounted injector delivered primary reference fuel with octane number 90 directly into the combustion chamber during the NVO. The measured results showed advanced combustion phase CA50 under the early start of injection (SOI) timings. Peak recompression pressures were lower than the motoring, emphasizing that the NVO reactions were net endothermic. Zero-dimensional kinetics calculations showed that classical reformate species increase almost linearly as a function of SOI timings.


    This work also presents the effects of intake boosting pressure and single versus double pulses injections on CA50, burn duration CA10-90, peak cylinder pressure, combustion noise metrics, thermal efficiency, and emissions. The combustion noise metrics were over the engine constraint limit under advanced SOI timings, but a double-pulse injection could reduce the combustion noise metrics and NOx emission. Late fuel injection in the intake stroke could reduce NOx to a single digit.

    DOI

  • Experimental Investigation of Direct Fuel Injection into Low-Oxygen Recompression Interval in a Homogenous Charge Compression Ignition Engine

    Ratnak Sok, Jin Kusaka

    Journal of Energy Resources Technology   144 ( 1 ) 1 - 8  2021年10月  [査読有り]  [国際誌]

    担当区分:筆頭著者, 責任著者

     概要を見る

    <title>Abstract</title>
    This work analyzed measured data from a single-cylinder engine operated under gasoline direction injection homogenous charge compression ignition (GDI-HCCI) mode. The experiments were conducted at a 0.95 equivalence ratio (φ) under 0.5 MPa indicated mean effective pressure and 1500RPM. A side-mounted injector delivered primary reference fuel (octane number 90) into the combustion chamber during negative valve overlap (NVO). Advanced combustion phase CA50 were observed as a function of the start of injection (SOI) timings. Under φ=0.95, peak NVO in-cylinder pressures were lower than motoring for single and split injections, emphasizing that NVO reactions were endothermic. Zero-dimensional kinetics calculations showed classical reformate species (C3H6, C2H4, CH4) from the NVO rich mixture increased almost linearly due to SOI timings, while H2 and CO were typically low. These kinetically reformed species shortened predicted ignition delays. This work also analyzed the effects of intake pressure and single versus double pulses injections on CA50, burn duration, peak cylinder pressure, combustion noise, thermal efficiency, and emissions. Advanced SOI (single-injection) generated excessive combustion noise metrics over constraint limits, but the double-pulse injection could significantly reduce the metrics (Ringing Intensity ≤ 5 MW/m2, Maximum Pressure Rise Rate = 0.6 MPa/CA) and NOx emission. The engine's net indicated thermal efficiency reached 41% under GDI-HCCI mode against 36% under SI mode for the same operating conditions. Under GDI-HCCI mode and without spark-ignition, late fuel injection in the intake stroke could reduce NOx to a single digit.

    DOI

    Scopus

    5
    被引用数
    (Scopus)
  • Effects of Partial Oxidation in an Unburned Mixture on a Flame Stretch under EGR Conditions

    Kei Yoshimura, Kohei Ozawa, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka, Masaaki Togawa, Satoshi Tokuhara

    SAE Technical Paper Series    2021年09月  [査読有り]

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • A Model for Predicting Turbulent Burning Velocity by using Karlovitz Number and Markstein Number under EGR Conditions

    Kei Yoshimura, Kohei Ozawa, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka, Masaaki Togawa, Satoshi Tokuhara

    SAE Technical Paper Series   ( 2021 )  2021年09月  [査読有り]

    DOI

    Scopus

    2
    被引用数
    (Scopus)
  • A Novel Integrated Series Hybrid Electric Vehicle Model Reveals Possibilities for Reducing Fuel Consumption and Improving Exhaust Gas Purification Performance

    Takehiro Yamagishi, Hajime Shingyouchi, Kyohei Yamaguchi, Norifumi Mizushima, Takahiro Noyori, Jin Kusaka, Toshinori Okajima, Ratnak Sok, Makoto Nagata

    SAE Technical Paper Series    2021年09月  [査読有り]

    担当区分:責任著者

    DOI

    Scopus

    3
    被引用数
    (Scopus)
  • Avoidance Algorithm Development to Control Unrealistic Operating Conditions of Diesel Engine Systems under Transient Conditions

    Rio Asakawa, Iku Tanabe, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka, Masatoshi Ogawa, Takuma Degawa, Shigeaki Kurita, Arravind Jeyamoorthy, Zhou Beini

    SAE Technical Paper Series    2021年09月  [査読有り]

    担当区分:責任著者

    DOI

    Scopus

    3
    被引用数
    (Scopus)
  • Reaction Analysis and Modeling of Fast SCR in a Cu-Chabazite SCR Catalyst Considering Generation and Decomposition of Ammonium Nitrate

    Keiichiro Seki, Rikuto Ueyama, Yoshihisa Tsukamoto, Kenya Ogawa, Kohei Oka, Ratnak Sok, Jin Kusaka

    SAE Technical Paper Series    2021年09月  [査読有り]

    担当区分:責任著者

    DOI

    Scopus

  • Numerical Study on the Adaptation of Diesel Wave Breakup Model for Large-Eddy Simulation of Non-Reactive Gasoline Spray

    Ratnak Sok, Beini Zhou, Jin Kusaka

    ASME Technical Paper    2021年07月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    <title>Abstract</title>
    Gasoline direct injection (GDI) is a promising solution to increase engine thermal efficiency and reduce exhaust gas emissions. The GDI operation requires an understanding of fuel penetration and droplet size, which can be investigated numerically. In the numerical simulation, primary and secondary breakup phenomena are studied by the Kelvin-Helmholtz/Rayleigh-Taylor (KH-RT) wave breakup models. The models were initially developed for diesel fuel injection, and in the present work, the models are extended to the GDI application combined using large-eddy simulation (LES). The simulation is conducted using the KIVA4 code.


    Measured data of experimental spray penetration and Mie-scattering image comparisons are carried out under non-reactive conditions at an ambient temperature of 613K and a density of 4.84 kg/m3. The spray penetration and structures using LES are compared with traditional Reynolds-Averaged Navier-Stokes (RANS). Grid size effects in the simulation using LES and RANS models are also investigated to find a reasonable cell size for future reactive gasoline spray/combustion studies. The fuel spray penetration and droplet size are dependent on specific parameters. Parametric studies on the effects of adjustable constants of the KH-RT models, such as time constants, size constants, and breakup length constant, are discussed. Liquid penetrations from the RANS turbulence model are similar to that of the LES turbulence model’s prediction. However, the RANS model is not able to capture the spray structure well.

    DOI

  • Experimental and Numerical Analysis on the Influences of Direct Fuel Injection Into Oxygen-Depleted Environment of a Homogeneous Charge Compression Ignition Engine

    Ratnak Sok, Kei Yoshimura, Kenjiro Nakama, Jin Kusaka

    Journal of Energy Resources Technology-ASME Transaction   143 ( 12 )  2021年03月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    <title>Abstract</title>
    The oxygen-depleted environment in the recompression stroke can convert gasoline fuel into light hydrocarbons due to thermal cracking, partial oxidation, and water-gas shift reactions. These reformate species can influence the combustion characteristics of gasoline direct injection homogeneous charge compression ignition (GDI-HCCI) engines. In this work, the combustion phenomena are investigated using a single-cylinder research engine under a medium load. The main combustion phases are experimentally advanced by direct fuel injection into the negative valve overlap (NVO) compared with that of intake stroke under single/double-pulse injections. NVO peak in-cylinder pressures are lower than that of motoring due to the limited O2 concentration, emphasizing that endothermic reactions occur during the overlap. This phenomenon limits the oxidation reactions, and the thermal effect is not pronounced. The zero-dimensional chemical kinetics results present the same increasing tendencies of classical reformed species of rich mixture such as C3H6, C2H4, CH4, CO, and H2 as functions of injection timings. Predicted ignition delays are shortened due to the additions of these reformed species. The influences of the reformates on the main combustion are confirmed by three-dimensional computational fluid dynamics (CFD) calculations, and the results show that OH radicals are advanced under NVO injections relative to intake stroke injections. Consequently, earlier heat release and cylinder pressure are noticeable. Parametric studies on the effects of injection pressure, double-pulse injection, and equivalence ratio on the combustion and emissions are also discussed experimentally.

    DOI

    Scopus

    10
    被引用数
    (Scopus)
  • A MODELING STUDY ON FUEL CONSUMPTION IMPROVEMENT OF A LIGHT-DUTY CNG TRUCK EQUIPPED WITH A HYBRID POWERTRAIN

    Ratnak Sok, Jin Kusaka, Hisaharu Nakashima, Makoto Akaike

    ASTFE Technical Paper    2021年  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

  • Prediction of Ultra-Lean Spark Ignition Engine Performances by Quasi-Dimensional Combustion Model With a Refined Laminar Flame Speed Correlation

    Ratnak Sok, Kyohei Yamaguchi, Jin Kusaka

    Journal of Energy Resources Technology-ASME Transaction   143 ( 3 )  2020年12月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    <title>Abstract</title>
    The turbulent combustion in gasoline engines is highly dependent on laminar flame speed SL. A major issue of the quasi-dimensional (QD) combustion model is an accurate prediction of the SL, which is unstable under low engine speeds and ultra-lean mixture. This work investigates the applicability of the combustion model with a refined SL correlation for evaluating the combustion characteristics of a high-tumble port gasoline engine operated under ultra-lean mixtures. The SL correlation is modified and validated for a five-component gasoline surrogate. Predicted SL values from the conventional and refined functions are compared with measurements taken from a constant-volume chamber under micro-gravity conditions. The SL data are measured at reference and elevated conditions. The results show that the conventional SL overpredicts the flame speeds under all conditions. Moreover, the conventional model predicts negative SL at equivalence ratio ϕ ≤ 0.3 and ϕ ≥ 1.9, while the revised SL is well validated against the measurements. The improved SL correlation is incorporated into the QD combustion model by a user-defined function. The engine data are measured at 1000–2000 rpm under engine load net indicated mean effective pressure (IMEPn) = 0.4–0.8 MPa and ϕ = 0.5. The predicted engine performances and combustions are well validated with the measured data, and the model sensitivity analysis also shows a good agreement with the engine experiments under cycle-by-cycle variations.

    DOI

    Scopus

    15
    被引用数
    (Scopus)
  • Experimental and Numerical Analysis on the Influence of Direct Fuel Injection Into O2-Depleted Environment of a GDI-HCCI Engine

    Ratnak Sok, Jin Kusaka

    ASME Technical Paper    2020年11月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    <title>Abstract</title>
    Injected gasoline into the O2-depleted environment in the recompression stroke can be converted into light hydrocarbons due to thermal cracking, partial oxidation, and water-gas shift reaction. These reformate species influence the combustion phenomena of gasoline direct injection homogeneous charge compression ignition (GDI-HCCI) engines. In this work, a production-based single-cylinder research engine was boosted to reach IMEPn = 0.55 MPa in which its indicated efficiency peaks at 40–41%. Experimentally, the main combustion phases are advanced under single-pulse direct fuel injection into the negative valve overlap (NVO) compared with that of the intake stroke. NVO peak in-cylinder pressures are lower than that of motoring, which emphasizes that endothermic reaction occurs during the interval. Low O2 concentration could play a role in this evaporative charge cooling effect. This phenomenon limits the oxidation reaction, and the thermal effect is not pronounced. For understanding the recompression reaction phenomena, 0D simulation with three different chemical reaction mechanisms is studied to clarify that influences of direct injection timing in NVO on combustion advancements are kinetically limited by reforming. The 0D results show the same increasing tendencies of classical reformed species of rich-mixture such as C3H6, C2H4, CH4, CO, and H2 as functions of injection timings. By combining these reformed species into the main fuel-air mixture, predicted ignition delays are shortened.


    The effects of the reformed species on the main combustion are confirmed by 3D-CFD calculation, and the results show that OH radical generation is advanced under NVO fuel injection compared with that of intake stroke conditions thus earlier heat release and cylinder pressure are noticeable. Also, parametric studies on injection pressure and double-pulse injections on engine combustion are performed experimentally.

    DOI

  • Numerical Methods on VVA and VCR Concepts for Fuel Economy Improvement of a Commercial CNG Truck

    Ratnak Sok, Kazuki Takeuchi, Kyohei Yamaguchi, Jin Kusaka

    SAE Technical Paper Series   ( 2020 )  2020年09月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

    Scopus

    6
    被引用数
    (Scopus)
  • Prediction of Ultra-Lean SI Engine Performance by QD-Combustion Model With an Improved Laminar Flame Speed

    Ratnak Sok, Jin Kusaka, Kyohei Yamaguchi

    ASME Technical Paper    2020年08月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    <title>Abstract</title>
    A quasi-dimensional (QD) simulation model is a preferred method to predict combustion in the gasoline engines with reliable results and shorter calculation time compared with multi-dimensional simulation. The combustion phenomena in spark ignition (SI) engines are highly turbulent, and at initial stage of the combustion process, turbulent flame speed highly depends on laminar burning velocity SL. A major parameter of the QD combustion model is an accurate prediction of the SL, which is unstable under low engine speed and ultra-lean mixture.


    This work investigates the applicability of the combustion model for evaluating the combustion characteristics of a high-tumble port gasoline engine operated under ultra-lean mixture (equivalence ratio up to ϕ = 0.5) which is out of the range of currently available SL functions initially developed for a single component fuel. In this study, the SL correlation is improved for a gasoline surrogate fuel (5 components). Predicted SL data from the conventional and improved functions are compared with experimental SL data taken from a constant-volume chamber under micro-gravity condition. The SL measurements are done at reference conditions at temperature of 300K, pressure of 0.1MPaa, and at elevated conditions whose temperature = 360K, pressure = 0.1, 0.3, and 0.5 MPaa. Results show that the conventional SL model over-predicts flame speeds under all conditions. Moreover, the model predicts negative SL at very lean (ϕ ≤ 0.3) and rich (ϕ ≥ 1.9) mixture while the revised SL is well validated with the measured data. The improved SL formula is then incorporated into the QD combustion model by a user-defined function in GT-Power simulation. The engine experimental data are taken at 1000 RPM and 2000 RPM under engine load IMEPn = 0.4–0.8 MPa (with 0.1 increment) and ϕ ranges are up to 0.5. The results shows that the simulated engine performances and combustion characteristics are well validated with the experiments within 6% accuracy by using the QD combustion model coupled with the improved SL. A sensitivity analysis of the model is also in good agreement with the experiments under cyclic variation (averaged cycle, high IMEP or stable cycle, and low IMEP or unstable cycle).

    DOI

  • A Fundamental Study on Combustion Characteristics in a Pre-Chamber Type Lean Burn Natural Gas Engine

    Masashi Tanamura, Shintaro Nakai, Mahoko Nakatsuka, Shota Taki, Kohei Ozawa, Beini Zhou, Ratnak Sok, Yasuhiro Daisho, Jin Kusaka

    SAE Technical Paper Series   2019-September ( September )  2019年09月  [査読有り]

    担当区分:責任著者

    DOI

    Scopus

    8
    被引用数
    (Scopus)
  • A Study on Combustion Characteristics of a High Compression Ratio SI Engine with High Pressure Gasoline Injection

    Takashi Kaminaga, Kyohei Yamaguchi, Sok Ratnak, Jin Kusaka, Takashi Youso, Tatsuya Fujikawa, Masahisa Yamakawa

    SAE Technical Paper Series   2019-September ( September )  2019年09月  [査読有り]

    DOI

    Scopus

    20
    被引用数
    (Scopus)
  • 0D/1D Turbulent Combustion Model Assessment from an Ultra-Lean Spark Ignition Engine

    Ratnak Sok, Kyohei Yamaguchi, Jin Kusaka

    SAE Technical Paper Series   2019-March ( March )  2019年03月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

    Scopus

    13
    被引用数
    (Scopus)
  • Effect of Fuel Injection Timing During Negative Valve Overlap Period on a GDI-HCCI Engine

    Sok Ratnak, Jin Kusaka, Yasuhiro Daisho, Kei Yoshimura, Kenjiro Nakama

    Volume 1: Large Bore Engines; Fuels; Advanced Combustion   1  2018年11月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    Gasoline Direct Injection Homogeneous Charge Compression (GDI-HCCI) combustion is achieved by closing early the exhaust valves for trapping hot residual gases combined with direct fuel injection. The combustion is chemically controlled by multi-point auto-ignition which its main combustion phase can be controlled by direct injection timing of fuel. This work investigates the effect of single pulse injection timing on a supercharged GDI-HCCI combustion engine by using a four-stroke single cylinder engine with a side-mounted direct fuel injector.


    Injection of primary reference fuel PRF90 under the near-stoichiometric-boosted condition is studied. The fuel is injected during negative valve overlap (NVO) or recompression period for fuel reformation under low oxygen concentration and the injection is retarded to intake stroke for the homogeneous mixture. It is found that the early fuel injection in NVO period advances the combustion phasing compared with the retarded injection in the intake stroke. Noticeable slower combustion rate from intake stroke fuel injection is obtained compared with the NVO injection due to charge cooling effect. Zero-dimensional combustion simulations with multiple chemical reaction mechanisms are simulated to provide chemical understanding from the effect of fuel injection timing on intermediate species generations. The species such as C2H4, C3H6, CH4, and H2 are found to be formed during the NVO injection period from the calculations. The effects of single pulse injection timings on combustion characteristics such pressure rise rate, combustion stability, and emissions are also discussed in this study.

    DOI

  • Experiments and Simulations of a Lean-Boost Spark Ignition Engine for Thermal Efficiency Improvement

    Ratnak Sok, Jin Kusaka, Yasuhiro Daisho, Kei Yoshimura, Kenjiro Nakama

    SAE International Journal of Engines   9 ( 1 ) 379 - 396  2015年11月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    &lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;Primary work is to investigate premixed laminar flame propagation in a constant volume chamber of iso-octane/air combustion. Experimental and numerical results are investigated by comparing flame front displacements under lean to rich conditions. As the laminar flame depends on equivalence ratio, temperature, and pressure conditions, it is a main property for chemical reaction mechanism validation. Firstly, one-dimensional laminar flame burning velocities are predicted in order to validate a reduced chemical reaction mechanism. A set of laminar burning velocities with pressure, temperature, and mixture equivalence ratio dependences are combined into a 3D-CFD calculation to compare the predicted flame front displacements with that of experiments. It is found that the reaction mechanism is well validated under the coupled 1D-3D combustion calculations. Next, lean experiments are operated in a SI engine by boosting intake pressure to maintain high efficiency without output power penalty. The peak indicated thermal efficiency are finally achieved under λ=1.3 with intake manifold absolute pressure 150 kPa in experiment. Data of in-cylinder pressure and rate of heat release from the 3D-CFD simulations combined with the validated chemical reaction mechanism are reproduced. NOx emissions from experiment and simulation are also in good agreements under the lean-boost combustion. Further thermal efficiency improvements of the lean-boost SI engine are investigated numerically by using dilution rate, high induced in-cylinder flow, and high knock resistant fuel. The peak indicated thermal efficiency and load of the SI engine is achieved. In addition, methods to prevent knock for high efficiency spark ignition engine are also discussed.&lt;/div&gt;&lt;/div&gt;

    DOI

  • Thermal Efficiency Improvement of a Lean-Boosted Spark Ignition Engine by Multidimensional Simulation with Detailed Chemical Kinetics

    Sok Ratnak, Kusaka Jin, Daisho Yasuhiro, Yoshimura Kei, Nakama Kenjiro

    International Journal of Automotive Engineering   6 ( 4 ) 97 - 104  2015年06月  [査読有り]

    担当区分:筆頭著者, 責任著者

     概要を見る

    This paper aims to improve thermal efficiency of spark ignition engine by numerical calculation with detailed chemistry. Experimental results from a four-stroke-single-cylinder engine are compared with that of simulations. It is experimentally found that peak efficiency is achieved at lean-limit combustion under excess air ratio λ=1.6. Due to engine output power loss, further investigations are conducted under lean-boost operations. The best condition of the lean-boost mode is at λ=1.3 and 150 kPa boosted pressure (abs). To further improve the efficiency without power loss, simulations are conducted under lean-boost combustion with dilution rate, high engine swirl, and high knock resistant fuel.

    DOI CiNii

    Scopus

    20
    被引用数
    (Scopus)
  • 3D Simulations on Premixed Laminar Flame Propagation of iso-Octane/Air Mixture at Elevated Pressure and Temperature

    Sok Ratnak, Jin Kusaka, Yasuhiro Daisho

    SAE Technical Paper Series   2015-March ( March )  2015年03月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

    Scopus

    8
    被引用数
    (Scopus)
  • Computational Study to Improve Thermal Efficiency of Spark Ignition Engine

    Sok Ratnak, Kohei Katori, Jin Kusaka, Yasuhiro Daisho, Kei Yoshimura, Nakama Kenjiro

    SAE Technical Paper Series   2015-March ( March )  2015年03月  [査読有り]

    担当区分:筆頭著者, 責任著者

    DOI

    Scopus

    12
    被引用数
    (Scopus)
  • THE EFFECT OF BIODIESEL FUEL FROM RUBBER (HEVEA BRASILIENSIS) SEED OIL ON A DIRECT INJECTION (DI) DIESEL ENGINE

    Iman Reksowardojo, Hung Ngoc Bui, Ratnak Sok, Athol Kilgour, Tirto Brodjonegoro, Tatang Soerawidjaja, Mai Xuan Pham, Toshio Shudo, Wiranto Arismunandar

    ASEAN Engineering Journal   1 ( 1 ) 65 - 81  2011年03月  [査読有り]  [国際誌]

    担当区分:責任著者

▼全件表示

講演・口頭発表等

  • Modeling analysis on combined effects of VVT/VCR engine technology to reduce fuel consumption of light-duty parallel hybrid CNG trucks

    Ratnak Sok, Jin Kusaka, Hisaharu Nakashima, Hidetaka Minagata

    ASME International Mechanical Engineering Congress and Exposition @ Columbus, OH  

    発表年月: 2022年11月

    開催年月:
    2022年10月
    -
    2022年11月
  • Thermoelectric generation from exhaust heat in electrified natural gas trucks - part 1: modeling and baseline analysis on engine system efficiency improvement

    Ratnak Sok, Jin Kusaka, Hisaharu Nakashima, Hidetaka Minagata

    ASME International Mechanical Engineering Congress and Exposition @ Columbus, OH  

    発表年月: 2022年11月

    開催年月:
    2022年10月
    -
    2022年11月
  • Thermoelectric exhaust heat recovery to maximize brake thermal efficiency of advanced diesel engines: modeling and baseline analysis

    Ratnak Sok, Jin Kusaka

    ASME Internal Combustion Engine Division Fall Technical Conference @ Indianapolis  

    発表年月: 2022年10月

    開催年月:
    2022年10月
     
     
  • Development and Comparison of Virtual Sensors Constructed using AI Techniques to Estimate the Performances of IC engines

    Arravind Jeyamoorthy, Takuma Degawa, Ratnak Sok, Toshikado Akimichi, Shigeaki Kurita, Masatoshi Ogawa, Takayuki Takei, Ikuta Hayashi, Jin Kusaka, Beini Zhou, Kyohei Yamaguchi, Iku Tanabe

    SAE Powertrains, Fuels & Lubricants Conference & Exhibition @ Krakow, Poland  

    発表年月: 2022年09月

    開催年月:
    2022年09月
     
     
  • Effects of Partial Oxidation in an Unburned Mixture on Turbulent Combustion with Ethanol-Blended Gasoline Surrogate Fuels toward Higher Thermal Efficiency of Spark-Ignition Engines with Renewable Fuels

    Kei Yoshimura, Kohei Isobe, Mitsutaka Kawashima, Satoshi Tokuhara, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka

    SAE Powertrains, Fuels & Lubricants Conference & Exhibition @ Krakow, Poland  

    発表年月: 2022年09月

    開催年月:
    2022年09月
     
     
  • A Model for Predicting Turbulent Burning Velocity with Low-Temperature Oxidation Reactions in Unburned Mixtures

    Kohei Isobe, Kei Yoshimura, Satoshi Tokuhara, Mitsutaka Kawashima, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka

    SAE Powertrains, Fuels & Lubricants Conference & Exhibition @ Krakow, Poland  

    発表年月: 2022年09月

    開催年月:
    2022年09月
     
     
  • Effects of Partial Oxidation and Octane Sensitivity on Flame Stretch Rate at Extinction under EGR Conditions Potential of Renewable Fuels toward Higher Thermal Efficiency of Spark-ignition Engines

    Kei Yoshimura, Kohei Isobe, Satoshi Tokuhara, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka

    COMODIA 2022 -The 10th International Conference on Modeling and Diagnostics for Advanced Engine Systems  

    発表年月: 2022年07月

    開催年月:
    2022年07月
     
     
  • Waste Heat Recovery via Thermoelectric Generation in Light-Duty Natural Gas Electrified Trucks: -Part1: Integrated Engine System Modeling and Baseline Analysis-

    Ratnak Sok, Jin Kusaka, Hisaharu Nakashima, Hidetaka Minagata

    ASTFE Thermal and Fluids Engineering Conference (TFEC) @ University of Nevada, LV  

    発表年月: 2022年05月

    開催年月:
    2022年05月
     
     
  • On the Laminar Flame Speed Correlations to Improve Prediction Accuracy of a Phenomenological Combustion Submodel in an Ultra-Lean SI Engine

    Ratnak Sok, Kyohei Yamaguchi, Jin Kusaka, Hidefumi Kataoka

    2021 JSAE 32nd Internal Combustion Engine Symposium  

    開催年月:
    2021年12月
     
     
  • Prediction of Potential Fuel Economy Improvements of an Electrified Natural Gas Truck Equipped With a VVT/VCR Engine

    Ratnak Sok, Jin Kusaka, Hisaharu Nakashima, Makoto Akaike, Hidetaka Minagata

    ASME 2021 International Mechanical Engineering Congress and Exposition  

    発表年月: 2021年11月

    開催年月:
    2021年11月
     
     
  • Experimental Investigation on the Effects of Direct Fuel Injection Into Low-O2 Recompression Interval of an HCCI Engine

    Ratnak Sok, Jin Kusaka

    ASME 2021 International Mechanical Engineering Congress and Exposition  

    発表年月: 2021年11月

    開催年月:
    2021年11月
     
     
  • A Model for Predicting Turbulent Burning Velocity by using Karlovitz Number and Markstein Number under EGR Conditions

    Kei Yoshimura, Kohei Ozawa, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka, Masaaki Togawa, Satoshi Tokuhara

    SAE Powertrains, Fuels & Lubricants Digital Summit  

    発表年月: 2021年09月

    開催年月:
    2021年09月
     
     
  • Effects of Partial Oxidation in an Unburned Mixture on a Flame Stretch under EGR Conditions

    Kei Yoshimura, Kohei Ozawa, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka, Masaaki Togawa, Satoshi Tokuhara

    SAE Powertrains, Fuels & Lubricants Digital Summit  

    発表年月: 2021年09月

    開催年月:
    2021年09月
     
     
  • Fast Nonlinear Model Predictive Control Using Machine Learning for Air Path Control of a Diesel Engine

    Kyohei Yamaguchi, Keisuke Yokota, Rio Asakawa, Iku Tanabe, Ratnak Sok, Beini Zhou, Jin Kusaka, Masatoshi Ogawa, Takuma Degawa, Shigeaki Kurita

    SAE Powertrains, Fuels & Lubricants Digital Summit  

    開催年月:
    2021年09月
     
     
  • A Novel Integrated Series Hybrid Electric Vehicle Model Reveals Possibilities for Reducing Fuel Consumption and Improving Exhaust Gas Purification Performance

    Takehiro Yamagishi, Hajime Shingyouchi, Kyohei Yamaguchi, Norifumi Mizushima, Takahiro Noyori, Jin Kusaka, Toshinori Okajima, Ratnak Sok, Makoto Nagata

    SAE Powertrains, Fuels & Lubricants Digital Summit  

    発表年月: 2021年09月

  • Avoidance Algorithm Development to Control Unrealistic Operating Conditions of Diesel Engine Systems under Transient Conditions

    Rio Asakawa, Iku Tanabe, Kyohei Yamaguchi, Ratnak Sok, Jin Kusaka, Masatoshi Ogawa, Takuma Degawa, Shigeaki Kurita, Arravind Jeyamoorthy, Zhou Beini

    SAE 15th International Conference on Engines & Vehicles @ Capri, Italy  

    発表年月: 2021年09月

    開催年月:
    2021年09月
     
     
  • Reaction Analysis and Modeling of Fast SCR in a Cu-Chabazite SCR Catalyst Considering Generation and Decomposition of Ammonium Nitrate

    Keiichiro Seki, Rikuto Ueyama, Yoshihisa Tsukamoto, Kenya Ogawa, Kohei Oka, Ratnak Sok, Jin Kusaka

    SAE 15th International Conference on Engines & Vehicles @ Capri, Italy  

    発表年月: 2021年09月

    開催年月:
    2021年09月
     
     
  • Numerical Study on the Adaptation of Diesel Wave Breakup Model for Large-Eddy Simulation of Non-Reactive Gasoline Spray

    Ratnak Sok, Beini Zhou, Jin Kusaka

    ASME 2021 Power Conference  

    発表年月: 2021年07月

  • A MODELING STUDY ON FUEL CONSUMPTION IMPROVEMENT OF A LIGHT-DUTY CNG TRUCK EQUIPPED WITH A HYBRID POWERTRAIN

    Ratnak Sok, Jin Kusaka, Hisaharu Nakashima, Makoto Akaike

    ASTFE 5-6th Thermal and Fluids Engineering Conference (TFEC)  

    発表年月: 2021年05月

  • Experimental and Numerical Analysis on the Influence of Direct Fuel Injection into O2-Depleted Environment of a GDI-HCCI Engine

    Ratnak Sok, Jin Kusaka

    ASME 2020 Internal Combustion Engine Division Fall Technical Conference, USA  

    発表年月: 2020年

  • Prediction of Ultra-Lean SI Engine Performance by QD-Combustion Model With an Improved Laminar Flame Speed

    Ratnak Sok, Kyohei Yamaguchi, Jin Kusaka

    ASME 2020 Power Conference collocated with the 2020 International Conference on Nuclear Engineering, USA  

    発表年月: 2020年

  • Numerical Methods on VVA and VCR Concepts for Fuel Economy Improvement of a Commercial CNG Truck

    Ratnak Sok, Kazuki Takeuchi, Kyohei Yamaguchi, Jin Kusaka

    SAE Powertrains, Fuels & Lubricants Meeting, Poland  

    発表年月: 2020年

  • Roles of Computer-Aided-Engineering on Vehicle Powertrain Research & Development

    Ratnak Sok  [招待有り]

    National Polytechnic Institute of Cambodia (Ministry of Labor and Vocational Training)  

    発表年月: 2019年08月

  • Roles of Computer-Aided Engineering on Vehicle Powertrain Research & Development

    Ratnak Sok  [招待有り]

    Institut de Technologie du Cambodge  

    発表年月: 2019年08月

  • A Fundamental Study on Combustion Characteristics in a Pre-Chamber Type Lean Burn Natural Gas Engine

    Masashi Tanamura, Shintaro Nakai, Mahoko Nakatsuka, Shota Taki, Kohei Ozawa, Beini Zhou, Ratnak Sok, Yasuhiro Daisho, Jin Kusaka

    14th International Conference on Engines & Vehicles, Italy  

    発表年月: 2019年

  • 0D/1D Turbulent Combustion Model Assessment from an Ultra-Lean Spark Ignition Engine

    Ratnak Sok, Kyohei Yamaguchi, Jin Kusaka

    Asia-Pacific Automotive Engineering Conference, Thailand  

    発表年月: 2019年

  • A Study on Combustion Characteristics of a High Compression Ratio SI Engine with High Pressure Gasoline Injection

    Takashi Kaminaga, Kyohei Yamaguchi, Sok Ratnak, Jin Kusaka, Takashi Youso, Tatsuya Fujikawa, Masahisa Yamakawa

    14th International Conference on Engines & Vehicles, Italy  

    発表年月: 2019年

  • Effect of Fuel Injection Timing During Negative Valve Overlap Period on a GDI-HCCI Engine

    Ratnak Sok, Jin Kusaka, Yasuhiro Daisho, Kei Yoshimura, Kenjiro Nakama

    ASME 2018 Internal Combustion Engine Division Fall Technical Conference, USA  

    発表年月: 2018年

  • 3D Simulations on Premixed Laminar Flame Propagation of iso-Octane/Air Mixture at Elevated Pressure and Temperature

    Ratnak Sok, Jin Kusaka, Yasuhiro Daisho

    18th Asia Pacific Automotive Engineering Conference, Australia  

    発表年月: 2015年

  • Computational Study to Improve Thermal Efficiency of Spark Ignition Engine

    Ratnak Sok, Kohei Katori, Jin Kusaka, Yasuhiro Daisho, Kei Yoshimura, Nakama Kenjiro

    18th Asia Pacific Automotive Engineering Conference, Australia  

    発表年月: 2015年

  • Experiments and Simulations of a Lean-Boost Spark Ignition Engine for Thermal Efficiency Improvement

    Ratnak Sok, Jin Kusaka, Yasuhiro Daisho, Kei Yoshimura, Kenjiro Nakama

    SAE/JSAE Small Engines Technology Conference, Japan  

    発表年月: 2015年

  • Numerical and Experimental Studies on Flame Propagation of Iso-octane in a Constant Volume Chamber

    Ratnak Sok, Jin Kusaka

    The Proceedings of the National Symposium on Power and Energy Systems, Japan  

    発表年月: 2014年

  • Studies of Hydroxy (HHO) gas Addition on Performance and Exhaust gas Emissions of a Compression Ignition Engine fuelled with Rubber Seed Methyl Ester

    Ratnak Sok, IK REKSOWARDOJO, T PRAKOSO, Toshio Shudo, Wiranto Arismunandar

    JICA AUN/SEED-Net 5th Regional Conference on New and Renewable Energy, Vietnam  

    発表年月: 2011年

  • The Effect of Biodiesel Fuel from Rubber (Hevea brasiliensis) Seed Oil on a Direct Injection Diesel Engine

    Iman Reksowardojo, Hung Ngoc Bui, Ratnak Sok, Athol Kilgour, Tirto Brodjonegoro, Tatang Soerawidjaja, Mai Xuan Pham, Toshio Shudo, Wiranto Arismunandar

    3rd AUN/SEED-Net Regionale Conférence, New and Renewable Energy @ Penang, Malaysia  

    発表年月: 2010年10月

  • The Study of Biodiesel from Rubber (Hevea Brasiliensis) Seed Oil with HHO Gas Additive on a DI Engine

    Ratnak Sok, Iman REKSOWARDOJO, Tirto PRAKOSO, Toshio Shudo, Wiranto Arismunandar

    The 2nd Conference on Engineering and Technology, Cambodia  

    発表年月: 2010年

  • Experimental Study on the Performances of Yanmar NS70 Diesel Engine using Jatropha Curcas Oil

    Ratnak Sok, Sovanna Pan, Sopheak Rey  [招待有り]

    Asian Youth Energy Summit, Singapore  

    発表年月: 2008年

▼全件表示

共同研究・競争的資金等の研究課題

  • MBD on battery thermal management of BEVs

    Automotive supplier 

    研究期間:

    2022年
    -
    2024年
     

    Jin Kusaka, Ratnak Sok

  • Thermal management MBD of PHEV

    Automotive OEM 

    研究期間:

    2022年
    -
    2024年
     

    Jin Kusaka, Ratnak Sok

  • Compact passenger car engine designs via MBD

    Automotive Industry 

    研究期間:

    2018年
    -
    2024年
     

    Jin Kusaka, Ratnak Sok, Kyohei Yamaguchi

  • Development of high-efficiency gas engine for power generation by controlling flow of decarbonized fuels

    NEDO 

    研究期間:

    2021年
    -
    2022年
     

    Beini Zou, Kyohei Yamaguchi, Ratnak Sok

  • Reducing CO2 emissions by optimizing the combustion method and diesel surrogate blending of future engines

    Petroleum and Automotive Associations 

    研究期間:

    2021年
    -
    2022年
     

    Jin Kusaka, Beini Zhou, Ratnak Sok

  • MBD Approach to improve fuel economy of natural gas hybrid trucks

    Energy supplier 

    研究期間:

    2018年
    -
    2021年
     

    Jin Kusaka, Ratnak Sok

  • ML-based MPC controller development for engine control

    Automotive Supplier 

    研究期間:

    2018年
    -
    2021年
     

    Jin Kusaka, Kyohei Yamaguchi, Ratnak Sok, Beini Zhou

  • Gasoline Engine Control

    European automotive supplier 

    研究期間:

    2019年
    -
    2020年
     

    Hiroyuki Ishii, Jin Kusaka, Ratnak Sok, Kyohei Yamaguchi

  • SIP Innovative Combustion Technology

    JST 

    研究期間:

    2014年
    -
    2019年
     

  • LBE Program: Education Capacity Building by Lab-Based Education Improvement

    Japan International Cooperation Agency 

    研究期間:

    2017年
    -
    2018年
     

    Ratnak Sok, Sovanna Pan (within a whole research unit)

  • High-efficiency engine development for subcompact cars

    Automotive Industry 

    研究期間:

    2012年
    -
    2015年
     

  • Utilisation of Biogas from Animal Waste and Biomass from Agricultural Waste in Internal Combustion Engine

    Japan International Cooperation Agency 

    研究期間:

    2011年
    -
    2012年
     

    (ITC: Sopheak Rey, Ratnak Sok), (Kyoto Univ: Masahiro Shioji)

  • Design of threshing machine for agricultural use

    Japan International Cooperation Agency 

    研究期間:

    2011年
    -
    2012年
     

    Dara To, Ratnak Sok

  • Development of a Small Scale Biomass Gas Generator

    Japan International Cooperation Agency 

    研究期間:

    2011年
    -
    2012年
     

    Ratnak Sok, Dara To

  • Performance and Durability Test of Mixed Combustion of Jatropha Curcas L. Oil and Biogas for Power Generation

    NEDO 

    研究期間:

    2011年
    -
    2012年
     

    (ITC: Rey Sopheak, Sovanna Pan, Ratnak Sok, Thavarith Chunhieng, Romny Om) (Chugoku EPCO: Yukimasa Yamamura, Ichiro Uchiyama, Toshiki Yamasaki, Akifumi Nakamura, Yoshihisa Shimizu)

  • LBE Program: Education Capacity Building by Lab-Based Education Improvement

    Japan International Cooperation Agency 

    研究期間:

    2011年
    -
    2012年
     

    Ratnak Sok, Sopheak Rey, Sovanna Pan (within a whole research unit)

▼全件表示

 

担当経験のある科目(授業)

  • TA on Thermal energy reaction engineering

    早稲田大学  

    2018年
    -
    継続中
     

  • TA on Thermal energy reaction engineering

    早稲田大学  

    2012年
    -
    2015年
     

  • ICEs, GD&T Fundamentals, Material Sciences

    National Polytechnics Institute of Cambodia  

    2011年
    -
    2012年
     

  • ICEs, Machine elements, mechanical constructions

    2011年
    -
    2012年
     

 

学術貢献活動

  • Editorial board members in SAE International

    学術調査

    2022年
    -
    継続中
  • https://www.frontiersin.org/journals/future-transportation/sections/transportation-emissions#editorial-board

    審査・学術的助言

    https://www.frontiersin.org/journals/future-transportation/sections/transportation-emissions#editorial-board  

    2022年
    -
    継続中
  • Topic Advisory Panel Member (10+ MDPI Journals)

    査読等

    2022年
    -
    継続中
  • Reviewer for 20+ Journals and Conferences (ASME, Elsevier, IEEE, SAE, SAGE, MDPI, Springer, Taylor&Francis)

    査読等

    2020年
    -
    継続中
  • Associate Chair (15th International ACM Conference on Automotive User Interfaces and Interactive Vehicular Applications)

    大会・シンポジウム等

    2023年09月
     
     
  • Event Committee (The 2nd International Electronic Conference on Processes: Process Engineering—Current State and Future Trends)

    大会・シンポジウム等

    2023年05月
     
     
  • Program Committee (2022 IEEE International Conference on Artificial Intelligence in Engineering and Technology)

    大会・シンポジウム等

    2022年09月
     
     

▼全件表示

学内研究所・附属機関兼任歴

  • 2022年
    -
    2024年

    カーボンニュートラル社会研究教育センター   兼任センター員