2024/06/15 更新

写真a

クサカ ジン
草鹿 仁
所属
理工学術院 大学院環境・エネルギー研究科
職名
教授
学位
工学博士 ( 早稲田大学 )

所属学協会

  •  
     
     

    日本機械学会

  •  
     
     

    日本燃焼学会

  •  
     
     

    米国自動車技術会

  •  
     
     

    自動車技術会

研究分野

  • 熱工学

研究キーワード

  • エンジン、燃料電池、バッテリー、触媒

受賞

  • 自動車技術会 優秀講演賞

    2005年10月  

  • 米国自動車学会 SETC 2003 優秀論文賞

    2003年10月  

  • 自動車技術会 浅原賞学術奨励賞

    2001年05月  

 

論文

  • Novel virtual sensors development based on machine learning combined with convolutional neural-network image processing-translation for feedback control systems of internal combustion engines

    Ratnak Sok, Arravind Jeyamoorthy, Jin Kusaka

    Applied Energy   365   123224 - 123224  2024年07月

    DOI

    Scopus

  • Measured Thermal Performances at Brick and Module Levels in a Battery Pack of a Mid-Size Electric Vehicle under WLTC and FTP Cycles

    Kamaleshwar Nandagopal, Ratnak Sok, Kentaro Kishida, Tomohiro Otake, Jin Kusaka

    SAE Technical Paper Series    2024年04月

     概要を見る

    <div class="section abstract"><div class="htmlview paragraph">Performances of battery electric vehicles (BEV) are affected by the thermal imbalance in the battery packs under driving cycles. BEV thermal management system (VTMS) should be managed efficiently for optimal energy consumption and cabin comfort. Temperature changes in the brick, module, and pack under the repeated transient cycles must be understood for model-based development. The authors conducted chassis dynamometer experiments on a fully electric small crossover sports utility vehicle (SUV) to address this challenge. A BEV is tested using a hub-type, 4-wheel motor chassis dynamometer with an air blower under the Worldwide Harmonized Light Vehicles Test Cycle (WLTC) and Federal Test Procedures (FTP) with various ambient temperatures. The mid-size BEV with dual-motor featured 80 thermocouples mounted on the 74-kWh battery pack, including the cells, upper tray, side cover, and pack cover. The authors analyzed battery pack temperature distribution behavior by changing the battery’s initial state of charge (SOC) and cell temperatures.</div><div class="htmlview paragraph">Performance metric data such as battery voltage, current, SOC, pack temperature, coolant properties, pressure drop, and flow rate are recorded and analyzed. The results show the temperature variations under diverse driving conditions, with an average difference of 1°C between modules and 2.3°C between bricks in module 1, and a maximum temperature difference of 3.9°C is recorded in the battery pack. The results provide valuable insights into the optimal operational range for maintaining battery pack temperature stability. The measured results can provide a fundamental understanding of the peak temperature location on the brick-to-brick and pack-to-pack variation under transient cycles. These results provide a fundamental understanding of the thermal performance of battery brick, module, and pack, which can be used to develop a VTMS model.</div></div>

    DOI

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  • Development and Validation of a Battery Thermal Management Model for Electric Vehicles under Cold Driving

    Yunkui Ma, Ratnak Sok, Enbo Cui, Kentaro Kishida, Kamaleshwar Nandagopal, Yuto Ozawa, Jin Kusaka

    SAE Technical Paper Series    2023年10月

     概要を見る

    <div class="section abstract"><div class="htmlview paragraph">Battery thermal management system (BTMS) significantly improves battery electric vehicle (BEV) performance, especially under cold weather. A tradeoff between battery power consumption and cabin heating performance must be considered in cold driving conditions. This preliminary study aims to develop an integrated battery pack and coolant channel model to predict the thermal behavior of a BEV thermal management system. In this study, we develop and calibrate the physical baseline model with testbench data using finite element and CFD software. First, an electrochemical battery cell 1D model (Pseudo-2D or P2D) is built and calibrated against the cell reference data. An integrated pack model consisting of four modules (each has 23 and 25 bricks and a total of 4416 cells) with coolant flow channels is developed using reference and benchmarked data. Then, the model is calibrated against experimental results from a mass-production, mid-size battery-electric SUV operated under cold driving conditions at a constant vehicle speed of 60 km/h for 5800 sec. The integrated model considers the heat transfer characteristics from cell-to-brick and brick-to-coolant channels. As a result, a thermodynamic model that can predict the average battery temperature rise, temperature changes, and pressure drops of the coolant of the battery pack is constructed. The result shows that the battery pack model can predict the coolant pressure drop of the pack with a mean absolute percentage error (MAPE) of 0.49 % and the coolant temperature rise with a 5.23% MAPE. The calibrated battery pack model can reasonably reproduce the terminal voltage with a MAPE of 0.30%. A 3D-CFD simulation result of the battery brick model is also reported on the cell-to-cell temperature distribution of 46 cells.</div></div>

    DOI

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    1
    被引用数
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  • Experimental and 3D-CFD Analysis of Synthetic Fuel Properties on Combustion and Exhaust Gas Emission Characteristics in Heavy-Duty Diesel Engines

    Kunihiro Shimizu, Tomoki Narushima, Ratnak Sok, Jin Kusaka

    SAE Technical Paper Series    2023年08月

     概要を見る

    <div class="section abstract"><div class="htmlview paragraph">Synthetic fuels can significantly improve the combustion and emission characteristics of heavy-duty diesel engines toward decarbonizing heavy-duty propulsion systems. This work analyzes the effects of engine operating conditions and synthetic fuel properties on spray, combustion, and emissions (soot, NOx) using a supercharging single-cylinder engine experiment and KIVA-4 code combined with CHEMKIN-II and in-house phenomenological soot model. The blended fuel ratio is fixed at 80% diesel and 20% n-paraffin by volume (hereafter DP). Diesel, DP1 (diesel with n-pentane C5H12), DP2 (diesel with n-hexane C6H14), and DP3 (diesel with n-heptane C7H16) are used in engine-like-condition constant volume chamber (CVC) and engine experiments.</div><div class="htmlview paragraph">Boosted engine experiments (1080 rpm, common-rail injection pressure 160 MPa, multi-pulse injection) are performed using the same DP fuel groups under various main injection timings, pulse-injection intervals, and EGR = 0-40%. Once the 3D-CFD model is validated with the CVC and experimental engine data, in-cylinder combustion and emissions are analyzed. The CVC experiments show that DP2 and DP3 liquid penetrations are shorter than diesel oil. In engine tests, NOx did not change much for all DP fuels for the same engine operating condition. However, shorter-penetrated DP2 and DP3 reduce soot emissions by more than 60% and CO without worsening brake-specific fuel consumption compared to diesel oil. The 3D-CFD results show that n-hexane shifts the penetration of the high-carbon number to the low-carbon fuel. Vapor penetrations are found to be shortened by blending low-volatility fuels with diesel oil. Visualizations of the in-cylinder confirmed a decrease in the amount of soot formation near the wall for DP2 and DP3 fuels. In addition, equivalence ratio – temperature (phi-T) maps of these fuels indicate that at 40% EGR, soot emissions are reduced at lower equivalence ratios than diesel oil.</div></div>

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  • Effects of Pre-Chamber Internal Shape on CH <sub>4</sub> -H <sub>2</sub> Combustion Characteristics Using Rapid-Compression Expansion Machine Experiments and 3D-CFD Analysis

    Yixin Feng, Ryo Yamazaki, Ratnak Sok, Jin Kusaka

    SAE Technical Paper Series    2023年08月

     概要を見る

    <div class="section abstract"><div class="htmlview paragraph">Pre-chamber (PC) natural gas and hydrogen (CH<sub>4</sub>-H<sub>2</sub>) combustion can improve thermal efficiency and greenhouse gas emissions from decarbonized stationary engines. However, the engine efficiency is worsened by prolonged combustion duration due to PC jet velocity extinction. This work investigates the impact of cylindrical PC internal shapes to increase its jet velocity and shorten combustion duration. A rapid compression and expansion machine (RCEM) is used to investigate the combustion characteristics of premixed CH<sub>4</sub> gas. The combustion images are recorded using a high-speed camera of 10,000 fps. The experiments are conducted using two types of long PC shapes with diameters <i>φ=</i>4 mm (hereafter, long<i>φ</i>4) and 5 mm (hereafter, long <i>φ</i>5), and their combustions are compared against a short PC shape (<i>φ</i>=12 mm). For all designs of the PC shapes, the PC holes are 6 with 2 mm in diameter. Initial recorded results using only CH<sub>4</sub> show that jet extinction does not occur using the short and long 5mm types. The combustion duration of <i>φ</i>=4 mm PC is the shortest compared to the short-type and 5 mm PC. With CH<sub>4</sub>-H<sub>2</sub> blending (0%H<sub>2</sub>, 10%H<sub>2</sub>, 20%H<sub>2</sub>) and 4 mm shape, the combustion durations of 10%H<sub>2</sub> and 20%H<sub>2</sub> can be shortened compared to the CH<sub>4</sub>-only case (0%H<sub>2</sub>). However, the jet extinction probability is not zero.</div><div class="htmlview paragraph">3D-CFD combustion simulations are performed using CONVERGE software, and a 1/6 sector-mesh, GRI-Mech 3.0, G-equation combustion, and law-of-wall models are utilized in conjunction with RNG k-epsilon turbulence model. Simulated in-cylinder pressure and burning rate are validated against the recorded data. PC jet velocity, turbulent kinetic energy (TKE) of the main chamber, PC jet temperature, total heat loss in PC, and PC heat loss rate of 12 mm, 4 mm, and 5 mm are compared. Experimental combustion images and 3D-CFD temperature distribution with and without H<sub>2</sub> blending are also reported. The results show that long PC types can accelerate the jet velocity and shorten combustion duration. The jet extinction can be prevented by designing a small PC diameter area larger than the nozzle’s cross-sectional area. With H<sub>2</sub> blending, laminar burning velocity increases, and the jet ejection timing can be advanced. The result shows that the combustion duration can be shortened by 15 degrees using CH<sub>4</sub>-20%H<sub>2</sub> against CH<sub>4</sub> only.</div></div>

    DOI

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  • Effects of Pre-spark Heat Release of Ethanol-Blended Gasoline Surrogate Fuels on Engine Combustion Behavior

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

    SAE International Journal of Fuels and Lubricants   null ( null )  2023年05月

     概要を見る

    <div>Regulations limiting greenhouse gas (GHG) emissions in the transport sector have become more restrictive in recent years, drawing interest to synthetic fuels such as e-fuels and biofuels that could “decarbonize” existing vehicles. This study focuses on the potential to increase the thermal efficiency of spark-ignition (SI) engines using ethanol as a renewable fuel, which requires a deep understanding of the effects of ethanol on combustion behavior with high compression ratios (CRs). An important phenomenon in this condition is pre-spark heat release (PSHR), which occurs in engines with high CRs in boosted conditions and changes the fuel reactivity, leading to changes in the burning velocity. Fuel blends containing ethanol display high octane sensitivity (OS) and limited low-temperature heat release (LTHR). Consequently, their burning velocities with PSHR may differ from that of gasoline. This study therefore aimed to clarify the effects of ethanol on SI combustion behavior under PSHR conditions. Combustion behavior was studied by performing single-cylinder engine experiments and chemical kinetics simulations. The experimental measurements were performed to characterize the relationship between the occurrence of PSHR and the main combustion duration. Analysis of this relationship showed that the ethanol-blended fuel has a lesser PSHR and a longer combustion duration than the non-ethanol fuel by approximately 5% in high engine load conditions. Simulations using input data from the experiments revealed that the ethanol-blended fuel has a lower laminar burning velocity due to the lower temperature in the unburned mixture caused by its PSHR. Additional simulations examining the chemical effect of partially oxidized reactants caused by PSHR on the laminar burning velocity showed that partially oxidized reactants increase the laminar burning velocity of the ethanol-blended fuel but decrease that of a reference fuel without ethanol. A large number of fuel radicals and oxides of the ethanol-blended fuel enhances chain-branching reactions in the pre-flame zone and possibly increases its laminar burning velocity. However, the thermodynamic effect of PSHR on laminar burning velocity exceeds the chemical effect, and thus the ethanol-blended fuel has a lower turbulent burning velocity in the PSHR conditions.</div>

    DOI

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    2
    被引用数
    (Scopus)
  • 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

    DOI

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    11
    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]

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    5
    被引用数
    (Scopus)
  • Experimental and Numerical Analysis of the Effects of Thermal Degradation on Carbon Monoxide Oxidation Characteristics of a Three-Way Catalyst

    Sota Aoyama, Yunosuke Kubo, Ratnak Sok, Jin Kusaka

       2023年

    DOI

  • Impacts of Pre-Spark Heat Release on Unstretched Laminar Burning Velocity in Advanced Flex-Fuel Gasoline-Ethanol Engines

    Kohei Isobe, Kei Yoshimura, Takuma Kobayashi, Ratnak Sok, Jin Kusaka

       2023年

    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

    DOI

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    13
    被引用数
    (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]

    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]

    DOI

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  • 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

     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

  • 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08月

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    3
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  • 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

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    11
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  • 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

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    1
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  • 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

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    2
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  • 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

  • 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

    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   143 ( 12 )  2021年12月

     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

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    10
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  • Experimental Investigation on the Effects of Direct Fuel Injection Into Low-O2 Recompression Interval of an HCCI Engine

    Ratnak Sok, Jin Kusaka

    Volume 8A: Energy    2021年11月

     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

  • 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]

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    2
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  • 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]

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    3
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  • 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]

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    3
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  • Modeling on a Three-Way Catalyst Used in Series Hybrid Electric Vehicles Focusing on Its Catalytic Behavior at Cold Start

    Toshinori Okajima, Suchitra Sivakumar, Hajime Shingyouchi, Kyohei Yamaguchi, Jin Kusaka, Makoto Nagata

    Industrial & Engineering Chemistry Research    2021年09月

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    4
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  • 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     1 - 25  2021年09月

     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.

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    5
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  • 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

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  • 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

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    4
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  • 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    2021年07月

     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

  • 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   143 ( 3 )  2021年03月

     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.

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    18
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  • Modeling on a Three-Way Catalyst Used in Series Hybrid Electric Vehicles Considering Its Specific Engine Operation Attribute

    Toshinori Okajima, Suchitra Sivakumar, Hajime Shingyouchi, Kyohei Yamaguchi, Jin Kusaka, Makoto Nagata

    Industrial & Engineering Chemistry Research   60 ( 4 ) 1583 - 1601  2021年02月

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    4
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  • 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

    Proceeding of 5-6th Thermal and Fluids Engineering Conference (TFEC)    2021年

    DOI

  • Gas-wall heat flux analysis on PCI combustion by using the one-dimensional model (Effect of change in heat loss under transient operation)

    Kyohei YAMAGUCHI, Yuta KOMAN, Iku TANABE, Keiki TANABE, Jin KUSAKA

    Transactions of the JSME (in Japanese)    2021年

    DOI

  • 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    2020年11月

     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 Papers   ( 2020 )  2020年09月

     概要を見る

    © 2020 SAE International. All rights reserved. Natural gas has been used in spark-ignition (SI) engines of natural gas vehicles (NGVs) due to its resource availability and stable price compared to gasoline. It has the potential to reduce carbon monoxide emissions from the SI engines due to its high hydrogen-To-carbon ratio. However, short running distance is an issue of the NGVs. In this work, methodologies to improve the fuel economy of a heavy-duty commercial truck under the Japanese Heavy-Duty Driving Cycle (JE05) is proposed by numerical 1D-CFD modeling. The main objective is a comparative analysis to find an optimal fuel economy under three variable mechanisms, variable valve timing (VVT), variable valve actuation (VVA), and variable compression ratio (VCR). Experimental data are taken from a six-cylinder turbocharged SI engine fueled by city gas 13A. The 9.83 L production engine is a CR11 type with a multi-point injection system operated under a stoichiometric mixture. For minimizing optimal valve strategy selections and engine testing procedures, a one-dimensional engine model is developed in GT-Power software using experimental data and engine specifications provided by a project partner. The model is built using the same theory as of spark-ignition engines. Knock prediction is based on the Shell model, and a spark timing optimization logic is coupled to the model. In-cylinder pressure, rate of heat release, brake mean effective pressure, and maximum brake torque spark ignition timings are well reproduced, as compared with that of 12 experimental operating points under engine speed and load variations. In order to build a baseline brake specific fuel consumption (BSFC) map in the driving cycle, the simulation model is used to generate 51 BSFC points, as proposed in the JE05 cycle under speed-Torque changes. From the baseline engine model, the average fuel economy of the heavy-duty natural gas truck is 4.14 km/L. 0.5 % and 2.43% of simulated fuel economy improvements are found when the engine is operated under VVT and VVA mechanisms (fixed lifts), respectively. Significant fuel economy improvement is achieved at about 6.31% under VCR engine operation compared with the baseline engine model.

    DOI

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    8
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  • Prediction of ultra-lean SI engine performance by QD-combustion model with an improved laminar flame speed

    Ratnak Sok, Jin Kusaka, Kyohei Yamaguchi

    American Society of Mechanical Engineers, Power Division (Publication) POWER   2020-August  2020年

     概要を見る

    Copyright © 2020 ASME. 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 hightumble 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 userdefined 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

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  • 気体燃料と軽油の二元燃料を適用した圧縮着火機関の燃焼室形状最適化による気体燃料の未燃排出低減

    山口 恭平, 草鹿 仁

    自動車技術会論文集   51 ( 1 ) 32 - 38  2020年01月  [査読有り]

  • 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]

    DOI

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    13
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  • 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 Papers   2019-September ( September )  2019年09月

     概要を見る

    © 2019 SAE International and © 2019 SAE Naples Section. All rights reserved. In order to improve thermal efficiency of spark ignition (SI) engines, an improved technology to avoid irregular combustion under high load conditions of high compression ratio SI engines is required. In this study, the authors focused on high pressure gasoline direct injection in a high compression ratio SI engine, which its rapid air-fuel mixture formation, turbulence, and flame speed, are enhanced by high-speed fuel spray jet. Effects of fuel injection pressure, injection and spark ignition timing on combustion characteristics were experimentally and numerically investigated. It was found that the heat release rate was drastically increased by raising the fuel injection pressure. The numerical simulation results show that the high pressure gasoline direct injection enhanced small-scale turbulent intensity and fuel evaporation, simultaneously. These two effects were considered as the main factors to increase the flame propagation speed, suggesting a new combustion concept different from conventional SI combustion controlled by in-cylinder bulk flow. This combustion method enables the delay of fuel injection and spark ignition timing up to near top dead center (TDC) which leads to avoid pre-ignition and knocking by shortening the end-gas reaction time. Therefore, it was shown that the irregular combustion in a high compression ratio SI engine could be avoided by utilizing high pressure gasoline injection, which leads to improve partial load thermal efficiency without affecting the high load performance.

    DOI

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    26
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  • 0D/1D turbulent combustion model assessment from an ultra-lean spark ignition engine

    Ratnak Sok, Kyohei Yamaguchi, Jin Kusaka

    SAE Technical Papers   2019-March ( March )  2019年03月

     概要を見る

    © 2019 SAE International. All Rights Reserved. This paper focuses on an assessment of predictive combustion model using a 0D/1D simulation tool under high load, different excess air ratio ?, and different combustion stabilities (based on coefficient of variation of indicated mean effective pressure COVimep). To consider that, crank angle resolved data of experimental pressure of 500 cycles are recorded under engine speed 1000 RPM and 2000 RPM, wide-open throttle, and ?=1.0, 1.42, 1.7, and 2.0. Firstly, model calibration is conducted using 18 cases at 2000 RPM using 500 cycle-averaged in-cylinder pressure to find optimized model constants. Then, the model constants are unchanged for other cases. Next, different cycle-averaged pressure data are used as inputs in the simulation based on the COVimep for studying sensitivity of the turbulent model constants. The simulation is conducted using 1D simulation software GT-Power. Firstly, a three-pressure analysis (TPA) model (intake, in-cylinder, exhaust) for experimental prediction and optimization of burn rate shape are studied. Boundary conditions such as the three pressure histories, intake/exhaust valves timings, boundary temperatures, and exhaust gas emissions are used as model inputs. Errors of indicated thermal efficiency, indicated mean effective pressure, and CA50 are within 3%. Predicted parameters from the TPA model such as air volumetric efficiency, trapped air/fuel vapor mass, trapped residual gas fraction, tumble, and surface temperature of the piston, head, and valves are used as initializations in the predictive combustion model. A built-in flame propagation model, termed as SITurb, is investigated whether it can replicate the in-cylinder pressure and burn rate shapes. A revised laminar flame speed correlation of five-component gasoline surrogate is incorporated in the combustion model via an encrypted dynamic link library file. The results show that thermodynamic histories of the combustion are reproducible under high load and stoichiometric-to-ultra-lean conditions. Under all cases, only turbulent flame speed multiplier needs to be calibrated.

    DOI

    Scopus

    14
    被引用数
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  • 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

    PROCEEDINGS OF THE ASME INTERNAL COMBUSTION ENGINE FALL TECHNICAL CONFERENCE, 2018, VOL 1    2019年

     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 H-2 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.

  • 予混合CO成分がディーゼル予混合圧縮着火燃焼に及ぼす影響

    山口恭平, 永塚勇斗, 草鹿仁, 大聖泰弘, 鈴木央一

    日本機械学会論文集   84 ( 867 )  2018年11月  [査読有り]

  • 燃料改質を適用した圧縮着火エンジンに関する数値解析

    山口恭平, 喜久里陽, 草鹿仁, 大聖泰弘

    自動車技術会論文集   49 ( 2 ) 150 - 155  2018年03月  [査読有り]

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

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

    SAE INTERNATIONAL JOURNAL OF ENGINES   9 ( 1 ) 379 - 396  2016年04月

     概要を見る

    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 lambda = 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.

  • 小型ディーゼルエンジンにおける多段噴射による熱損失低減と熱効率向上に関する研究

    佐田翼, 伊藤聡一郎, 喜久里陽, 草鹿仁, 大聖泰弘, 山口恭平, 鈴木央一, 石井素

    自動車技術会論文集   46 ( 4 ) 755 - 761  2015年07月  [査読有り]

  • Computational Study to Improve Thermal Efficiency of Spark Ignition Engine

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

    SAE Technical Papers   2015-March ( March )  2015年03月

     概要を見る

    Copyright © 2015 SAE International. The objective of this paper is to investigate the potential of lean burn combustion to improve the thermal efficiency of spark ignition engine. Experiments used a single cylinder gasoline spark ignition engine fueled with primary reference fuel of octane number 90, running at 4000 revolution per minute and at wide open throttle. Experiments were conducted at constant fueling rate and in order to lean the mixture, more air is introduced by boosted pressure from stoichiometric mixture to lean limit while maintaining the high output engine torque as possible. Experimental results show that the highest thermal efficiency is obtained at excess air ratio of 1.3 combined with absolute boosted pressure of 117 kPa. Three dimensional computational fluid dynamic simulation with detailed chemical reactions was conducted and compared with results obtained from experiments as based points. The potential to improve further the efficiency, exhaust gas recirculation (EGR), high engine swirl ratio and high research octane number are good candidates for this improvement. In further calculations, we use simulated EGR ratio, high engine swirl ratio, RON95 fuels. To prevent the combustion from knock in the simulations when ignition timing is at maximum brake torque, simulated pressure probes are mounted on each side of intake and exhaust valves to detect knock pressure. By using these methods, spark timing of the engine can be advanced thus improve the thermal efficiency. It is found that, by combining lean-boosted/EGR and high octane-number fuel, higher thermal efficiency of spark ignition engine can be achieved.

    DOI

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    12
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  • 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 Papers   2015-March ( March )  2015年03月

     概要を見る

    Copyright © 2015 SAE International. This paper aims to validate chemical kinetic mechanisms of surrogate gasoline three components fuel by calculating one-dimensional laminar burning velocity of iso-octane/air mixture. Next, the application of level-set method on premixed combustion without consideration the effect of turbulence eddies on flame front is also studied in three-dimensional computational fluid dynamic (3D-CFD) simulation. In the 3D CFD simulation, there is an option to calculate laminar burning velocity by using empirical correlations, however it is applicable only for particular initial pressure and temperature in spark ignition engine cases. One-dimensional burning velocities from lean to rich of iso-octane/air mixture are calculated by using CHEMKIN-PRO with detailed chemistry and transport phenomena as a function of different equivalence ratios, different unburnt temperature and pressure ranges. A set of laminar flame table is then combined with 3D-CFD calculations with chemical kinetic mechanisms to track flame front displacements. A high-speed video camera at a frame speed of 2000 frames/sec is used to record the experimental flame positions of iso-octane/air combustion in a cylindrical shape constant volume combustion chamber (CVC). Different fuel-air equivalence ratios φ from lean to rich mixtures, ranging from 0.8 to1.4, are investigated at initial temperature of 420 K and 0.3 MPa of ambient pressure. The coupled simulations of one-dimensional adiabatic laminar burning velocity and 3D-CFD well predicts thermodynamics analysis of pressure-time and rate of heat release-time history and visualizations of flame front positions. Temperature and chemical species distributions of flame reaction zone are reported in comparison to that of experiments.

    DOI

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    8
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  • Thermal efficiency improvement of a lean-boosted spark ignition engine by multidimensional simulation with detailed chemical kinetics

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

    International Journal of Automotive Engineering   6 ( 4 ) 97 - 104  2015年

     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

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    22
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  • 並列化明示ODEソルバーに結合された計算流体力学(CFD)コードを使用したディーゼル燃焼におけるすす発生の数値シミュレーション

    KIKUSATO Akira, KOGO Kazuya, ZHOU Beini, KUSAKA Jin, DAISHO Yasuhiro, SATO Kiyotaka, FUJIMOTO Hidefumi, TERASHIMA Hiroshi, MORII Youhi

    SAE Technical Paper Series (Society of Automotive Engineers)   2014-October  2014年10月  [査読有り]

    DOI J-GLOBAL

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    1
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  • Diesel engine optimization control methods for reduction of exhaust emission and fuel consumption

    Bambang Wahono, Harutoshi Ogai, Masatoshi Ogawa, Jin Kusaka, Yasumasa Suzuki

    2012 IEEE/SICE International Symposium on System Integration, SII 2012     722 - 727  2012年

     概要を見る

    The fuel efficiency and emission reductions are the two consistent drivers for diesel engine development. Although many control devices mounted in diesel engine and in addition to the development of individual emission control methods, optimization techniques are required to utilize these methods in finding optimal engine operating conditions efficiently. This research was focused on the minimization of nitrogen oxides (NOx) emission and soot emission, as well as improving brake specific fuel consumption (BSFC) and power in a single cylinder diesel engine, which can be modeled as a multi-objective optimization problem. Many approaches have been applied to multi-objective optimization problems. In recent years, particle swarm optimization (PSO) method has been successfully applied to different areas since its advent. It has been demonstrated that PSO is an effective method for optimization problem. © 2012 IEEE.

    DOI

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    9
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  • エンジンの応答曲面モデルと制御パラメータ最適化手法の開発

    小川 雅俊, 鈴木 泰政, 大貝 晴俊, 草鹿 仁

    計測自動制御学会論文集   47 ( 10 ) 501 - 510  2011年

     概要を見る

    With the problem of environmental pollution and energy depletion in recent years, a control technology which improves the performance of automobile engine has been demanded. This paper presents a method for construction of response surface model and a control parameter optimization method for automobile diesel engine in order to develop a model-based control system and the early development technique based on the model. The proposed method for construction of response surface model is able to efficiently-develop the response surface model that describes the multiple control parameters in relation to the characteristic value such as fuel consumption and emission. The proposed control parameter optimization method is able to quickly and efficiently calculate optimal control parameters to optimize evaluation item such as fuel consumption and emission based on the model.

    DOI CiNii

  • Modeling of diesel engine components for model-based control (second report): Prediction of combustion with high speed calculation diesel combustion model

    Yasumasa Suzuki, Jin Kusaka, Masatoshi Ogawa, Harutoshi Ogai, Shigeki Nakayama, Takao Fukuma

    SAE Technical Papers    2011年

     概要を見る

    This paper describes the development of a High Speed Calculation Diesel Combustion Model that predicts combustion-related behaviors of diesel engines from passenger cars. Its output is dependent on the engine's operating parameters and on input from on-board pressure and temperature sensors. The model was found to be capable of predicting the engine's in-cylinder pressure, rate of heat release, and NOx emissions with a high degree of accuracy under a wide range of operating conditions at a reasonable computational cost. The construction of this model represents an important preliminary step towards the development of an integrated Model Based Control system for controlling combustion in diesel engines used in passenger cars. © Copyright 2011 Society of Automotive Engineers of Japan, Inc. and SAE International.

    DOI

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    2
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  • Modeling of diesel engine components for model-based control (First Report): The construction and validation of a model of the Air intake system

    Toshitaka Nakamura, Yasumasa Suzuki, Jin Kusaka, Masatoshi Ogawa, Harutoshi Ogai, Shigeki Nakayama, Takao Fukuma

    SAE Technical Papers    2011年

     概要を見る

    Model based control design is an important method for optimizing engine operating conditions so as to simultaneously improve engines' thermal efficiency and emission profiles. Modeling of intake system that includes an intake throttle valve, an EGR valve and a variable geometry turbocharger was constructed based on conservation laws combined with maps. Calculated results were examined the predictive accuracy of fresh charge mass flow, EGR rate and boost pressure. © Copyright 2011 Society of Automotive Engineers of Japan, Inc. and SAE International.

    DOI

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    1
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  • Development of teaching materials for SI engine control exercise

    M. Ogawa, D. Wu, Y. Yeh, H. Ogai, J. Kusaka

    IFAC Proceedings Volumes (IFAC-PapersOnline)   8 ( PART 1 ) 59 - 64  2009年

     概要を見る

    With the problem of environmental pollution and energy depletion in recent years, a control technology which improves the performance of automobile engine is demanded. Therefore, there is a real need for cultivating human resources capable of understanding both the automobile engine and the control technology. This paper presents the development of teaching materials for Spark Ignition (SI) engine control exercise. The purpose of this work is for students to understand the engine characteristics and the actual engine control system using an engine simulator and hardware in the loop simulator (HILS). These teaching materials consist of a personal computer for designing control logic, a real-time arithmetic board, an experimental ECU, and an engine test bench. This work developed a simulation system in order to understand the engine characteristic of relation between the engine revolution, the ignition timing, and the throttle angel. Moreover, an engine starting control system of design base with ignition timing controller that changes the integral action parameter of PID controller is designed, and a real-time environment for engine is developed. The engine real-time simulation environment can load the designed control logic and the engine model into the real-time arithmetic board to run the real-time simulation and to confirm the characteristics of control parameters. In the future, when the engine simulator is connected with engine test bench and ECU, engine real-time simulation can be realized.

  • Engine Control Education System

    Dongmei Wu, Harutoshi Ogai, Masatoshi Ogawa, Mushikkachai Maruto, Jin Kusaka, Pengfei Rao

    2008 PROCEEDINGS OF SICE ANNUAL CONFERENCE, VOLS 1-7     2785 - 2788  2008年  [査読有り]

     概要を見る

    This paper presents an introduction of engine control education system. The education system is composed of PC hardware, high-speed arithmetic processing board, ECU, and engine test bench. This system can realize following functions: familiarize people with gasoline engine properties, do engine control simulation, design engine control system, and realize engine real-time simulation. In this paper, we designed basic engine control system and got simulation results, developed real-time simulation system, and realized real-time simulation by adjusting PID parameters. Further more, we can design new control system by improving the basic ones. When we connect engine control model to engine test bench and ECU, this system can realize virtual engine real-time simulation.

  • Knock Prediction Using Multi Dimensional Simulating on Gasoline Engine -(PartⅠ)A Studu on Gasoline Surrogate Mechanism-

    塚越崇博, 中間健二郎, 村瀬栄二, 草鹿仁, 大聖泰弘

    JSAE/JSME International Combustion Engine Symposium Proceedings    2005年12月

    CiNii

  • Knock Prediction Using Multi Dimensional Simulating on Gasoline Engine -(PartⅡ)Knock Prediction on Gasoline Engines by Coupling with Turbulence Combustion Model and Simple Chemical Kinetics-

    中間健二郎, 村瀬栄二, 草鹿仁, 大聖泰弘

    International Combustion Engine Symposium Proceedings    2005年12月

    CiNii

  • 自動車用内燃機関の省エネルギー・低公害化技術

    草鹿 仁

    日本エネルギー学会誌 2005   84 ( 11 ) 903 - 907  2005年11月

     概要を見る

    This paper describes with internal combustion engines and fuel technologies trends toward reduction of both exhaust gas emissions and fuel consumption. The improvements of fuel consumption in gasoline engines will be achieved by the use of VVT (Variable Valve Train) system and homogeneous charge compression ignition combustion regime. The flexible common-rail injection system combined with advanced supercharging system can favorably reduced exhaust gas emissions of diesel engines without fuel penalty. Moreover, the new flexible combustion system must be developed for future automobiles. These engine technologies will be combined with future renewable fuels including GTL and biomass fuels, which lead to the reduction of CO_2 emission drastically.

    CiNii

  • ディーゼルエンジンの低公害化技術

    草鹿 仁

    NOK TECHNICAL REPORT   14   13 - 18  2005年10月

  • 圧縮自着火ガソリンエンジンの運転領域拡大の可能性 −数値シミュレーションを用いた極低負荷領域の自着火燃焼特性解析−

    村瀬栄二, 中間健二郎, 草鹿仁, 大聖泰弘

    自動車技術会論文集Vol.36 No.5 September 2005   36 ( 5 ) 53 - 58  2005年09月

    CiNii

  • 固体高分子燃料電池における輸送現象に関する基礎研究(第2報) −ガス流れ方向およびGDLの拡散性がセル性能におよぼす影響に関する検討−

    久保則夫, 福山陽介, 林浩己, 草鹿仁, 勝田正文, 大聖素弘

    自動車技術会論文集 Vol.36 No.5 September 2005   36 ( 5 ) 113 - 118  2005年09月

    CiNii

  • 固体高分子燃料電池における輸送現象に関する基礎研究(第3報) −低加湿運転時の分極特性に関する諸検討−

    久保則夫, 福山陽介, 上田直樹, 渡邊将司, 草鹿仁, 大聖素弘

    自動車技術会論文集 Vol.36 No.5 September 2005   36 ( 5 ) 119 - 124  2005年09月

    CiNii

  • ディーゼル燃焼の微粒子生成過程の解析

    森島彰紀, 草鹿仁, 大聖泰弘

    自動車技術会 学術講演会前刷集   66-05   1 - 6  2005年05月

  • 詳細な素反応過程を考慮した数値流体コードによるディーゼル燃焼の数値解析

    草鹿仁, 森島彰紀, 堀江信彦, 大聖泰弘

    自動車技術会 学術講演会前刷集   66-05   7 - 10  2005年05月

  • 詳細な素反応過程を考慮したGTTコードによるディーゼル燃焼の数値解析

    桑原史雄, 金山訓己, 荒居大樹, 草鹿仁, 脇坂知行, 大聖泰弘

    自動車技術会 学術講演会前刷集   66-05   15 - 18  2005年05月

  • 小型ディーゼルエンジンにおける着火・燃焼過程の数値解析

    堀江信彦, 草鹿仁, 西浦久泰, 大聖泰弘

    自動車技術会 学術講演前刷集   66-05   19 - 25  2005年05月

  • 詳細な素反応過程を考慮したディーゼル燃焼の数値シミュレーション

    草鹿仁

    自動車技術/自動車技術会   ( 59 ) 31 - 35  2005年01月

  • Numerical Simulation Accounting for the Finite-Rate Elementary Chemical Reactions for Computing Diesel Combustion Process

    Jin Kusaka, Nobuhiko Horie, Yasuhiro Daisho, V. I. Golovichev, Shigeki Nakayama

    SAE Technical Papers   2005-  2005年

     概要を見る

    To facilitate research and development of diesel engines, the universal numerical code for predicting diesel combustion has been favored for the past decade. In this paper, the finite-rate elementary chemical reactions, sometimes called the detailed chemical reactions, are introduced into the KIVA-3V code through the use of the Partially Stirred Reactor (PaSR) model with the KH-RT break-up, modified collision and velocity interpolation models. Outcomes were such that the predicted pressure histories have favorable agreements with the measurements of single and double injection cases in the diesel engine for use in passenger cars. Thus, it is demonstrated that the present model will be a useful tool for predicting ignition and combustion characteristics encountered in the cylinder.

    DOI

    Scopus

    11
    被引用数
    (Scopus)
  • ガソリンエンジンにおけるノッキング予測解析 −3次元CFDによる火炎伝播過程を考慮したノック発生位置予測の可能性−

    中間健二郎, 村瀬栄二, 草鹿仁, 大聖泰弘

    第42回燃焼シンポジウム講演論文集/日本燃焼学会     227 - 278  2004年12月

  • 固体高分子燃料電池における輸送現象に関する基礎研究(第1報)−分割電極セルを用いた実験とモデル計算による検討−

    久保則夫, 福山陽介, 真塩徹也, 坂元芳匡, 草鹿仁, 大聖素弘

    自動車技術会論文集   35 ( 4 ) 65 - 70  2004年10月

    CiNii

  • 直噴ディーゼル機関の機関性能を向上させる燃焼因子と燃料因子との組み合わせに関する研究

    菅野秀昭, 三藤祐子, 三ツ井裕太, 草鹿仁, 大聖泰弘

    学術講演前刷集/自動車技術会   79-04   15 - 20  2004年10月

    CiNii

  • 詳細な素反応過程を考慮した固体高分子型燃料電池用改質器の二次元輸送解析

    長崎央雅, 草鹿仁, 大聖泰弘

    学術講演前刷集/自動車技術会   88-04   5 - 8  2004年10月

  • 固体高分子型燃料電池における輸送現象に関する基礎研究

    久保則夫, 福山陽介, 真塩徹也, 草鹿仁, 大聖素弘

    学術講演前刷集/自動車技術会   88-04   9 - 12  2004年10月

  • 一人乗り燃料電池自動車の開発・設計

    玉川昌子, 加藤誠, 日暮克典, 大聖素弘, 久保則夫, 草鹿仁

    学術講演前刷集/自動車技術会   89-04   21 - 24  2004年10月

  • 多成分系燃料のディーゼル噴霧特性に関する数値シミュレーション

    吉見泰広, 村田豊, 長島巨樹, 桑原史雄, 菅野秀昭, 草鹿仁, 大聖泰弘

    学術講演前刷集/自動車技術会   98-04   11 - 14  2004年10月

  • 乗用車用ディーゼルエンジンの燃焼に関する研究 −燃料性状がPCI(Premixed Compression Ignition)燃焼に与える影響−

    草鹿仁, 鈴木和彦, 三好明, 大聖泰弘

    学術講演前刷集/自動車技術会   98-04   15 - 18  2004年10月

    CiNii

  • 圧縮自着火エンジンにおける運転パラメータの影響

    村瀬栄二, 中間健二郎, 西之宮賢, 草鹿仁, 大聖泰弘

    学術講演前刷集/自動車技術会   106-04   5 - 8  2004年10月

    CiNii

  • 天然ガスHCCI燃焼における排出ガス生成過程の解析

    桑山祥一, 草鹿仁, 大聖泰弘

    学術講演前刷集/自動車技術会   118-04   17 - 20  2004年10月

  • ガソリンエンジンにおけるノッキング予測解析

    中間健二郎, 村瀬栄二, 草鹿仁, 大聖泰弘

    学術講演会前刷集/自動車技術会   104-04   7 - 12  2004年10月

  • 中型ディーゼルエンジンにおけるUrea-SCRシステムに関する基礎研究

    末岡賢也, 高田圭, 大賀康史, 長崎央雅, 草鹿仁, 大聖泰弘

    学術講演前刷集/自動車技術会   29-04   17 - 20  2004年05月

  • 詳細な素反応過程を考慮したHCCI燃焼の数値流体シミュレーション

    草鹿 仁

    日本燃焼学会誌/日本燃焼学会   45 ( 136 ) 1 - 6  2004年05月

  • SAE(米国自動車学会) SETC 2003 優秀論文賞

    SAE(米国自動車学会)    2003年12月

  • 直噴ガソリンエンジン用スワールインジェクタ噴霧の燃料温度に対する影響の可視化

    村瀬 栄二, 草鹿 仁, 中間 健二郎, 豊田 俊司, 大聖 泰弘

    日本機械学会論文集(B編)   03;0121,69;688,pp.146-152 ( 688 ) 2706 - 2712  2003年12月

     概要を見る

    Fuel temperature in the injector of direct injection gasoline engine is high. On some conditions it exceeds over 410 K. In order to understand spray behavior and mixture processes on these conditions, the effects of fuel temperature on spray characteristics injected by a swirl type injector for direct injection gasoline engines were investigated; In experiments, a constant volume chamber is used to visualize spray and mixture formation processes by LASER sheet, shadow graph and schlieren techniques. In addition Sauter mean radius (SMR) were measured. As these results, increasing fuel temperature over saturated temperature roll up didn't exist, the spray width was narrow and the penetration length was extremely long. Moreover although evaporation occurred quickly, the fuel vapor mixed with the surrounding air incompletely. This is because spray gathered near the nozzle axis and roll up didn't exist.

    CiNii

  • 詳細な素反応過程を考慮した数値流体コードによるデュアルフュエルガスディーゼルエンジンの燃焼と排出ガス生成過程の解析

    伊藤 晋吾, 水嶋 教文, 草鹿 仁, 大聖 泰弘, 斎藤 孟

    自動車技術会論文集   34;4,pp.89-94 ( 4 ) 89 - 94  2003年10月

    CiNii

  • 減筒運転による4気筒デュアルフュエルガスディーゼルエンジンの燃焼及びトルク変動の改善

    水嶋 教文, 伊藤 晋吾, 草鹿 仁, 大聖 泰弘, 木原 良治, 斎藤 孟

    自動車技術会論文集   34;4,pp.81-87 ( 4 ) 81 - 87  2003年10月

    CiNii

  • Effects of High Temperature Fuel on In-Cylinder Fuel Mixture Formation Process for Direct Injection Engine

    SAE 2003   32;0003  2003年10月

  • 固体高分子形燃料電池における輸送現象に関する基礎研究

    学術講演前刷集/自動車技術会,2003年秋季大会   81;03,pp.1-6  2003年09月

  • 時間因子、乱流混合、及び燃焼室形状がHCCI燃焼の多次元シミュレーションに及ぼす影響

    飯田晋也

    学術講演前刷集/自動車技術会,2003年秋季大会   64;03,pp.13-16  2003年09月

    CiNii

  • Simulating Combustion and Exhaust Gas Emissions in a DI Diesel Engine by Using a CFD code Combined with Detailed Chemistry

    Journal of KONES Internal Combustion Engine 2003   10;1-2,pp.141-148  2003年09月

  • 詳細な素反応過程を考慮した燃焼、有害排出物質生成過程のモデリング

    草鹿 仁

    2003年度年次大会講演論文集/日本機会学会   7,pp.340-341   340 - 341  2003年08月

    DOI CiNii

  • Homogeneous charge compression ignition and combustion characteristics of natural gas mixtures: the visualization and analysis of combustion

    JSAE Review 24 (2003)   24,pp.33-40  2003年08月

  • Numercial Study on Combustion and Exhaust Gas Emissions Formation Processes of a Dual Fuel Natural Gas Engine By Using a Multi-Dimensional Model Combined with Detailed Chemical Kinetics

    2003 JSAE/SAE International Spring Fuels &amp; Lubricants Meeting    2003年05月

  • 粒子画像流速測定法(PIV法)を用いたエンジンシリンダ内流れ場の解析

    SUZUKI TECHNICAL REVIEW   pp.87-93  2003年03月

  • 詳細な素反応過程を考慮したエンジン燃焼のシミュレーション

    株式会社シーディー・アダプコジャパン第2回エンジンセミナー発表資料   pp.5-1,5-38  2003年02月

  • 各種燃料の燃焼特性

    JSAE/Symposium,Next Generation Fuel and Combustion,After Treatment and Lubricant   05;04,pp.14-21  2003年02月

  • A numerical study on combustion and exhaust gas emissions characteristics of a dual fuel natural gas engine using a multi-dimensional model combined with detailed kinetics

    Jin Kusaka, Shingo Ito, Norifumi Mizushima, Yasuhiro Daisho, Takeshi Saito

    SAE Technical Papers    2003年

     概要を見る

    Natural gas pre-mixture is ignited by a small amount of pilot fuel in the dual fuel engine. In this paper, numerical studies were carried out to investigate the combustion and exhaust gas emissions formation process of this engine type by using a multi dimensional model combined with the detailed chemical kinetics including 57 chemical species and 290 elementary reactions. In calculation, the effect of the pre-mixture concentration on combustion was examined. The result indicated that the increased concentration of natural gas could improve the burning fraction and THC, CO emissions due to the increased pre-mixture consumption rate and the cylinders gas temperature. Copyright © 2003 Society of Automotive Engineers of Japan, Inc.

    DOI

    Scopus

    8
    被引用数
    (Scopus)
  • 希薄天然ガス予混合気の圧縮着火と燃焼特性

    磯部 勇介, 安藤 太一, 春原 大輔, 大聖 泰弘, 草鹿 仁

    自動車技術会論文集   34;1,pp.59-64 ( 1 ) 59 - 64  2003年01月

    CiNii

  • Improvement of combustion in a dual fuel natural gas engine with half the number of cylinders

    Norifumi Mizushima, Shingo Ito, Jin Kusaka, Yasuhiro Daisho

    SAE Technical Papers    2003年

     概要を見る

    A dual fuel natural gas diesel engine suffers from remarkably lower thermal efficiency and higher THC, CO emissions at lower load because of its lower burned mass fraction caused by the lean pre-mixture. To overcome this inevitable disadvantage at lower load, two methods of reducing the number of operating cylinders were examined. One method was to use the two cylinders operation while the second one was to use the quasi-two cylinders operation. As a result, it was found that the unburned hydrocarbons and CO emissions could be favorably reduced with the improvement of thermal efficiency by reducing the number of cylinders to half for a dual fuel natural gas diesel engine. Moreover, it was also found that the quasi-two cylinders operation could improve the torque fluctuation more compared to the two cylinders operation. Copyright © 2003 Society of Automotive Engineers of Japan, Inc.

    DOI

    Scopus

    9
    被引用数
    (Scopus)
  • The effects of fuel temperature on a direct injection gasoline spray in a constant volume chamber

    Eiji Murase, Kenjiro Nakama, Shunji Toyoda, Jin Kusaka, Yasuhiro Daisho

    SAE Technical Papers    2003年

     概要を見る

    Fuel temperature in the injector of small direct injection gasoline engine is high. On some conditions it is higher than saturated temperature. Over saturated temperature spray characteristics greatly change. In order to predict in-cylinder phenomena accurately, it is important to understand spray behavior and mixture process above saturated temperature. Therefore spray shape, mixture formation process and Sauter mean radius were (SMR) measured in a constant volume chamber. And based on the measurement result initial spray boundary conditions were arranged so that spray characteristics over saturated temperature could be represented by using CFD code KIVA-3[1]. Moreover KIVA-3 code was combined with detailed chemical kinetics code Chemkin II to predict combustion products. [2] Calculated combustion process was validated with visualization of chemiluminescence. As a result, spray shape and penetration length have good agreement with measured ones for each fuel temperature. And also, tendencies of calculated flame propagation have roughly agreement with measured results and some species were predicted. Copyright © 2003 Society of Automotive Engineers of Japan, Inc.

    DOI

    Scopus

    4
    被引用数
    (Scopus)
  • Experimental and numerical studies on soot formation in fuel rich mixture

    Tomoyuki Narushima, Akinori Morishima, Haruki Moriwaki, Jin Kusaka, Yasuhiro Daisho

    SAE Technical Papers    2003年

     概要を見る

    Experimental and numerical studies are conducted on the formation of soot and Polycyclic Aromatic Hydrocarbons (PAHs), regarded as precursors of soot, during the combustion of fuel-rich homogeneous n-heptane mixtures. In-cylinder gases are sampled directly through a high-speed solenoid valve in engine tests, to be analyzed by GC/MS for qualifying PAHs. Smoke concentration is also measured. A numerical study is carried out by using a zero-dimensional model combined with detailed chemical kinetics. The experiments and computations show that PAHs can be predicted qualitatively by means of the present kinetic model. Copyright © 2003 Society of Automotive Engineers of Japan, Inc.

    DOI

    Scopus

    5
    被引用数
    (Scopus)
  • The effect of intake, injection parameters and fuel properties on diesel combustion and emissions

    Yuko Mito, Daisuke Tanaka, Seang Wock Lee, Yasuhiro Daisho, Jin Kusaka

    SAE Technical Papers    2003年

     概要を見る

    To improve urban air pollution, stringent emissions regulations for heavy-duty diesel engines have been proposed and will become effective in Japan, the EU, and the United States in a few years. To comply with such future regulations, it is critical to investigate the effects of intake and injection parameters and fuel properties on engine performance, efficiency and emissions characteristics, associated with the use of aftertreatment systems. An experimental study was carried out to identify such effects. In addition, the KIVA-3 code was used to gain insight into cylinder events. The results showed improvements in NOx-Smoke and BSFC trade-offs at high-pressure injection in conjunction with EGR and supercharging. Copyright © 2003 Society of Automotive Engineers of Japan, Inc.

    DOI

    Scopus

    6
    被引用数
    (Scopus)
  • Development and improvement of an ultra lightweight hybrid electric vehicle

    Makoto Kato, Hiroaki Yasuzawa, Jun Hasegawa, Yasuhiro Daisho, Ryoji Kihara, Jin Kusaka

    SAE Technical Papers    2003年

     概要を見る

    An experimental ultra lightweight compact vehicle named "the Waseda Future Vehicle" has been designed and developed, aiming at a simultaneous achievement of low exhaust gas emissions, high fuel economy and driving performance. The vehicle is powered by a dual-type hybrid system having a SI engine, electric motor and generator. A high performance lithium-ion battery unit is used for electricity storage. A variety of driving cycles were reproduced using the hybrid vehicle on a chassis dynamometer. By changing the logics and parameters in the electronic control unit (ECU) of the engine, a significant improvement in emissions was possible, achieving a very high fuel economy of 34 km/h at the Japanese 10-15 drive mode. At the same time, a numerical simulation model has been developed to predict fuel economy. This would be very useful in determining design factors and optimizing operating conditions in the hybrid power system. Copyright © 2003 Society of Automotive Engineers of Japan, Inc.

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • Mixture formation and combustion characteristics of directly injected LPG spray

    Seang-Wock Lee, Jin Kusaka, Yasuhiro Daisho

    SAE Technical Papers    2003年

     概要を見る

    It has been recognized that alternative fuels such as liquid petroleum gas (LPG) has less polluting combustion characteristics than diesel fuel. Direct-injection stratified-charge combustion LPG engines with spark-ignition can potentially replace conventional diesel engines by achieving a more efficient combustion with less pollution. However, there are many unknowns regarding LPG spray mixture formation and combustion in the engine cylinder thus making the development of high-efficiency LPG engines difficult. In this study, LPG was injected into a high pressure and temperature atmosphere inside a constant volume chamber to reproduce the stratification processes in the engine cylinder. The spray was made to hit an impingement wall with a similar profile as a piston bowl. Spray images were taken using the Schlieren and laser induced fluorescence (LIF) method to analyze spray penetration and evaporation characteristics. Combustion characteristics were examined visually by taking simultaneous images of the flame and OH radical formed during combustion. Numerical calculations using the KIVA-3 code was performed to predict mixture formation and combustion of LPG. The results showed that the LPG mixture moved along the impingement wall eventually reaching the spark plug location. The OH radical rose sharply and decreased gradually when combustion occurred vigorously. The predicted results from numerical calculations showed favorable agreement with measurements. Copyright © 2003 Society of Automotive Engineers of Japan, Inc.

    DOI

    Scopus

    13
    被引用数
    (Scopus)
  • Numerical study on iso-octane homogeneous charge compression ignition

    Shinya Iida, Jin Kusaka, Yasuhiro Daisho

    SAE Technical Papers    2003年

     概要を見る

    A numerical study was carried out to investigate auto-ignition characteristics during HCCI predicted by using zero and multi-dimensional models combined with detailed kinetics including 116 chemical species and 689 elementary reactions involving iso-octane. In the simulation, homogeneous charge compression ignition of the fuel was analyzed under the same conditions as encountered in internal combustion engines. The results elucidated the combustible region and oxidation process of iso-octane with the formation and destruction of various chemical species in the cylinder. Copyright © 2003 Society of Automotive Engineers of Japan, Inc.

    DOI

    Scopus

    1
    被引用数
    (Scopus)
  • A numerical study on ignition and combustion of a di diesel engine by using CFD code combined with detailed chemical kinetics

    Ken-Ichi Kohashi, Yoshinori Fujii, Jin Kusaka, Yasuhiro Daisho

    SAE Technical Papers    2003年

     概要を見る

    A CFD code combined with detailed chemical kinetics has been developed, linking with KIVA-3 and subroutines in CHEMKIN-II directly with some modifications. By using this CFD code, formation processes of combustion and exhaust gas emission for a turbo-charged DI diesel engine with common rail fuel injection system were simulated. As a result, formation processes of pollutant including NOx and soot were also considered according to the calculation results. The results show that NO caused by the extended Zeldvich mechanism accounted for about 88% of all NO, and it was found that there is a possibility to predict where and when soot will be formed by considering a simplified soot formation model. Copyright © 2003 Society of Automotive Engineers of Japan, Inc.

    DOI

    Scopus

    9
    被引用数
    (Scopus)
  • Experimental study on unregulated emission characteristics of turbocharged di diesel engine with common rail fuel injection system

    Keishi Takada, Futoshi Yoshimura, Yasushi Ohga, Jin Kusaka, Yasuhiro Daisho

    SAE Technical Papers    2003年

     概要を見る

    In this study, we selected four unregulated emissions species, formaldehyde, benzene, 1,3-butadiene and benzo[a]pyrene to research the emission characteristics of these unregulated components experimentally. The engine used was a water-cooled, 8-liter, 6-cylinder, 4-stroke-cycle, turbocharged DI diesel engine with a common rail fuel injection system manufactured for the use of medium-duty trucks, and the fuel used was JIS second-class light gas oil, which is commercially available as diesel fuel. The results of experiments indicate as follows: formaldehyde tends to be emitted under the low load condition, while 1,3-butadiene is emitted at the low engine speed. This is believed to be because 1,3-butadiene decomposes in a short time, and the exhaust gas stays much longer in a cylinder under the low speed condition than under the high engine speed one. Benzene is emitted under the low load condition, as it is easily oxidized in high temperature. Benzo[a]pyrene exists in the gas phase, because its boiling point is about 750K (at 128kPa). Once gaseous benzo[a]pyrene condenses, it is trapped by a filter with soot or sulfate. If it stays in the high temperature area, large part of it is oxidized. Consequently, benzo[a]pyrene is not emitted in great quantity under the high load condition. Copyright © 2003 SAE International.

    DOI

    Scopus

    36
    被引用数
    (Scopus)
  • Experimental and numerical studies on Particulate Matter formed in fuel rich mixture

    Akinori Morishima, Tomoyuki Narushima, Haruki Moriwaki, Jin Kusaka, Yasuhiro Daisho

    SAE Technical Papers    2003年

     概要を見る

    Experimental and numerical studies on PAHs (Polycyclic Aromatic Hydrocarbons) and PM (Particulate Matters) formed in the fuel rich mixture have been conducted. In the experiment, neat n-heptane and n-heptane with benzene 25 % by weight were chosen as test fuels. In-cylinder gases produced by the fuel-rich HCCI (Homogeneous Charge Compression Ignition) combustion were directly sampled and analyzed by the use of GC/MS (Gas Chromatograph/Mass Spectro- metry), and PM emission was also measured by PM sampling system to reveal characteristics of PM formation. Numerical study has been also carried out using a zero dimensional combustion model combined with detailed chemistry. Furthermore, simple surface growth of soot particles was integrated into a detailed chemical kinetic model, and validated with the experimental data. Copyright © 2003 SAE International.

    DOI

    Scopus

    2
    被引用数
    (Scopus)
  • A numerical study on combustion and exhaust gas emissions characteristics of a dual fuel natural gas engine using a multi-dimensional model combined with detailed kinetics

    Jin Kusaka, Shingo Ito, Norifumi Mizushima, Yasuhiro Daisho, Takeshi Saito

    SAE Technical Papers   111,pp.799-806  2003年

     概要を見る

    Natural gas pre-mixture is ignited by a small amount of pilot fuel in the dual fuel engine. In this paper, numerical studies were carried out to investigate the combustion and exhaust gas emissions formation process of this engine type by using a multi dimensional model combined with the detailed chemical kinetics including 57 chemical species and 290 elementary reactions. In calculation, the effect of the pre-mixture concentration on combustion was examined. The result indicated that the increased concentration of natural gas could improve the burning fraction and THC, CO emissions due to the increased pre-mixture consumption rate and the cylinders gas temperature. Copyright © 2003 Society of Automotive Engineers of Japan, Inc.

    DOI

    Scopus

    8
    被引用数
    (Scopus)
  • ウォ−ルガイド式直噴ガソリンエンジンの形状特性が燃焼に及ぼす影響

    村瀬 栄二, 中間 健二郎, 今田 正人, 草鹿 仁, 大聖 泰弘

    熱工学講演会講演論文集/日本機械学会   pp.445-446   445 - 446  2002年11月

     概要を見る

    It is necessary to modify port shapes for wall guided gasoline direct injection engine to make stratify mixture distribution. Modification of port shapes affects in-cylinder flow and combustion characteristics. In this study, using PIV method, flow characteristics of a port injection engine, which has two straight ports, shape and direct injection engine, which has a helical and a straight port, compared. Moreover, according to experimental results flow and combustion were calculated for another engine rotation speed. As a result, at medium speed range for DI engine, volumetric efficiency was deteriorated and combustion rate was improved due to increase turbulence intensity.

    DOI CiNii

  • 高温燃料噴霧が直噴エンジン筒内混合気分布形成過程に及ぼす影響

    中間 健二郎, 村瀬 栄二, 今田 正人, 草鹿 仁, 大聖 泰弘

    熱工学講演会講演論文集/日本機械学会   pp.443-444   443 - 444  2002年11月

     概要を見る

    Swirl injector spray at high fuel temperature has unipue characteristics compare with fuel temperature spray such as the strong penetration and narrow spray width. These characteristics have a possibility for improvement of fuel consumption and exhaust emission at cold start condition. Thus, Swirl injector spray at high fuel temperature condition by using multi components fuel evaporation was modeled in a CFD code to predict mixture formation process at cold engine start condition. As the results, high temperature fuel decreases wall film amount and increases vapor amount. It is concluded that high temperature fuel has a possibility for improvement of fuel consumption and exhaust emission at cold start condition.

    DOI CiNii

  • 固体高分子型燃料電池の運転条件が発電特性に及ぼす影響

    真塩 徹也, 宮田 幸一郎, 渡辺 正樹, 久保 則夫, 草鹿 仁, 大聖 泰弘

    熱工学講演会講演論文集/日本機械学会   pp.61-62   59 - 60  2002年11月

     概要を見る

    High power density is necessary for applying PEMFC to automotives. This paper describes with the effects of separator geometries on electric generation performance of PEMFC by the use of serpentine and column separators. The result indicates that PEMFC with serpentine separator achieves higher performance than with column separator. This can be explained by the fact that drainage capability of a serpentine type separator is superior to that of column with less contact resistance between a separator and a gas diffusion layer due to the increased contact area.

    DOI CiNii

  • 固体高分子型燃料電池のセパレータ形状が発電特性に及ぼす影響

    真塩 徹也, 宮田 幸一郎, 渡辺 正樹, 久保 則夫, 草鹿 仁, 大聖 泰弘

    熱工学講演会講演論文集/日本機械学会   pp.59-60   59 - 60  2002年11月

     概要を見る

    High power density is necessary for applying PEMFC to automotives. This paper describes with the effects of separator geometries on electric generation performance of PEMFC by the use of serpentine and column separators. The result indicates that PEMFC with serpentine separator achieves higher performance than with column separator. This can be explained by the fact that drainage capability of a serpentine type separator is superior to that of column with less contact resistance between a separator and a gas diffusion layer due to the increased contact area.

    DOI CiNii

  • 化学反応シミュレーションを用いたイソオクタン予混合圧縮着火に関する基礎的研究

    学術講演前刷集/自動車技術会,2002年秋季大会   pp.13-16  2002年11月

  • ディ−ゼル燃焼に及ぼす各種燃料噴射系と給気系因子の効果

    第17回内燃機関シンポジウム講演論文集/自動車技術会,日本機械学会共催   pp.211-216  2002年10月

  • 非定常噴霧の数値解析

    田中 大輔, 石井 素, 後藤 雄一, 草鹿 仁, 大聖 泰弘

    2002年度年次大会講演論文集/日本機会学会   4,pp.147-148   147 - 148  2002年09月

     概要を見る

    To improve the accuracy of the numerical fuel spray dynamics, Reitz's wave break-up model has been modified by Wakisaka et al. (MWB2), and incorporated into their GTT code. Both GTT and KIVA codes utilize the Discrete Droplet Model (DDM) for the fuel droplet dynamics, So we employed MWB2 in KIVA-3. This model was verified by comparing the calculated and experimental results at various pressures and temperatures in a constant volume vessel. The predicted tip penetration and SMD show good agreement with the measurements.

    DOI CiNii

  • 数値流体シミュレーションを用いたディーゼル燃焼の着火遅れに関する研究

    大賀 康史, 石井 素, 草鹿 仁, 後藤 雄一, 大聖 泰弘

    2002年度年次大会講演論文集/日本機会学会   4,pp.93-94   93 - 94  2002年09月

     概要を見る

    A numerical study was carried out to predict ignition delay times by using KIVA-3 combined with the ignition model, which is based on Livengood-Wu theory. N-heptane was selected on the basis of similarity of cetane number to diesel oil. The experimental data for n-heptane^<(1)> was referred to certify the adjustment of this model. The computational results show relatively good agreement between computational predictions and experiments.

    DOI CiNii

  • ディ−ゼル燃料の性状が噴霧及び燃焼に及ぼす影響

    自動車技術会論文集   33;3,pp.49-54  2002年07月

  • 高効率LPGエンジン開発のためのシミュレーションモデルの構築

    学術講演前刷集/自動車技術会,2002年夏季大会   pp.1-6  2002年07月

  • Two-dimensional laser induced fluorescence measurement of spray and OH radicals of LPG in constant volume chamber

    SW Lee, D Tananka, J Kusaka, Y Daisho

    JSAE REVIEW   23 ( 2 ) 195 - 203  2002年04月  [査読有り]

     概要を見る

    It is recognized that alternative fuels such as liquid petroleum gas (LPG) have less polluting combustion characteristics than diesel fuel. In this study, LPG was injected into a high pressure and temperature chamber to reproduce the stratification processes in an engine. The spray images were taken by the use of a PLIF method with Nd:YAG laser to analyze their penetration and evaporation characteristics. Also the characteristics of combustion were investigated by simultaneous visualization of OH radical and flames.
    The results show that the mixture moves along the impingement wall that reproduced the piston bowl and reaches the ignition spark plug. Also, OH fluorescence rises sharply and then decreases gradually when the combustion is carried out actively. (C) 2002 Society of Automotive Engineers of Japan, Inc. and Elsevier Science B.V. All rights reserved.

  • 燃料電池システムの発電特性に関する基礎研究

    講演前刷集/日本機会学会,関東学生会第41回学生員卒業研究発表講演会   pp.261-262  2002年03月

  • ディーゼルエンジンにおけるメタノールの利用技術

    草鹿 仁, 大聖 泰弘

    日本マリンエンジニアリング学会   37;2,pp.93-99 ( 2 ) 177 - 183  2002年

    DOI CiNii

  • 詳細な素反応過程を考慮した多次元モデルによるデュアルフューエルガスエンジンの燃焼と排出ガス特性に関する研究

    自動車技術会論文集   33;1,pp.23-30  2002年01月

  • Effects of diesel fuel characteristics on spray and combustion in a diesel engine

    S. W. Lee, Daisuke Tanaka, Jin Kusaka, Yasuhiro Daisho

    JSAE Review   23 ( 4 ) 407 - 414  2002年

     概要を見る

    Fuel properties play a dominant role in the spray, mixture formation and combustion process, and are a key to emission control and efficiency optimization. This paper deals with the influence of the fuel properties on the spray and combustion characteristics in a high-pressure and temperature chamber. Light diesel fuel spray and combustion images were taken by using a high-speed video camera and analyzed by their penetration and evaporation characteristics in comparison with current diesel fuel. Then, a single-cylinder DI engine was used to investigate combustion and exhaust characteristics. The mixture formation of the light diesel fuel is faster than that of the current fuel depending on physical properties like boiling point, density, viscosity and surface tension. Engine test results show that smoke is reduced without an increase in other emissions. © 2002 Society of Automotive Engineers of Japan, Inc. and Elsevier Science B.V. All rights reserved.

    DOI

    Scopus

    82
    被引用数
    (Scopus)
  • ディーゼルエンジンにおけるメタノール利用技術

    第66回(平成13年秋季)日本マリンエンジニアリング学会学術講演会講演論文集(別冊)   pp.160-165  2001年10月

  • 高温・高圧場における直噴ガソリン噴霧燃焼の可視化・解析

    村瀬 栄二, 中間 健二郎, 豊田 俊司, 草鹿 仁, 大聖 泰弘

    2001年度年次大会講演論文集/日本機会学会   01;09,pp.117-118   117 - 118  2001年08月

     概要を見る

    A mixture formation from a direct injection gasoline spray plays an important role of combustion and emission formation processes. A spray shape, which is related to the mixture formation, is influenced by ambient pressure, ambient temperature, fuel temperature and so on. In this study, the ambient temperature in the constant volume bomb was changed to investigate the effect of surrounding on spray shapes. Also the fuel temperature was changed. Moreover, OH radical from spray combustion was visualized by chemiluminescence. As a result, the injected spray behavior with high fuel temperature and these combustion characteristics were made clear.

    DOI CiNii

  • TABモデルを用いたスワールインジェクタ噴霧のモデル化

    中間 健二郎, 村瀬 栄二, 豊田 俊司, 草鹿 仁, 大聖 泰弘

    2001年度年次大会講演論文集/日本機会学会   2,pp.477-478   477 - 478  2001年08月

     概要を見る

    Various spray models were investigated to explain fuel spray formation and fuel mixing processes in DI engines. Based on TAB model, spray formation of the swirl injector that is currently used in conventional gasoline DI engines was modeled to an agreement with experimental results. As the results, the structure and the behavior of calculated swirl spray well agree with experimental results at different ambient conditions.

    DOI CiNii

  • 高温・高圧定容容器を用いたガソリン噴霧の可視化・解析

    村瀬栄二

    2001年度年次大会講演論文集/日本機会学会   2,pp.475-476   475 - 476  2001年08月

    CiNii

  • 燃料電池システムにおける各種燃料の改質特性

    岩下拓朗

    2001年度年次大会講演論文集/日本機会学会   2,pp.437-438 ( 1902 ) 437 - 438  2001年08月

    CiNii

  • Multi-Dimensional Modeling Combined with a Detailed Kinetics

    JSME-JSAE/The Fifth International Symposium on Diagnostics and Modeling of Combustion in Internal Combustion Engines COMODIA 2001   pp.346-352  2001年07月

  • Multi-Dimensional Modeling Combined with a Detailed Kinetics - Application for HCCI -

    Proceedings of The 2001 JAPAN-CHINA Workshop on Combustion and Its Latest Measuring Technology   pp.185-190  2001年07月

  • 予混合圧縮着火燃焼と化学反応速度論

    JSAE/Symposium,燃料性状とディーゼル微粒子   04;01,pp.7-15  2001年06月

  • エンジン燃焼と化学反応速度論

    草鹿 仁, 大聖 泰弘

    自動車技術/自動車技術会   55,pp.41-45 ( 6 ) 41 - 45  2001年06月

    CiNii

  • Combustion and Exhaust Gas Emissions Characteristics of a Glow-Assisted Methanol Engine - The Improvement of Combustion under Turbocharging Condition Combined with EGR by the Use of a Slit Injection Nozzle -

    学術講演会前刷集/自動車技術会,2001年春季大会   37;01,pp.9-12  2001年05月

  • 詳細な素反応過程を考慮したエンジン燃焼の多次元モデリング

    草鹿仁

    学術講演会前刷集/自動車技術会,2001年春季大会   31;01,pp.11-14 ( 2 ) 43 - 48  2001年05月

    CiNii

  • 自動車技術会 浅原賞学術奨励賞

    自動車技術会    2001年05月

  • 詳細な素反応過程を考慮した多次元モデルによる天然ガス予混合圧縮着火に関する基礎的研究

    草鹿 仁, 大聖 泰弘

    自動車技術会論文集   32;2,pp.43-48 ( 2 ) 43 - 48  2001年04月

    CiNii

  • 詳細な素反応過程を考慮した多次元モデルによるヂュアルフュエルガスエンジンの燃焼に関する基礎研究

    学術講演前刷集/自動車技術会,2001年秋季大会   114;01,pp.23-26  2001年

  • 減筒運転による天然ガスデュアルフュエルエンジンの性能・排出ガス特性

    学術講演前刷集/自動車技術会,2001年秋季大会   114;01,pp.11-14  2001年

  • 多環芳香族,微粒子の生成過程に関する基礎研究

    学術講演前刷集/自動車技術会,2001年秋季大会   110;01,pp.11-16  2001年

  • 化学反応シミュレーションを用いた天然ガス予混合圧縮着火に関する基礎的研究

    草鹿 仁, 岡本 多加志, 池田 哲也, 大聖 泰弘

    自動車技術会論文集   32;1,pp.29-34 ( 1 ) 29 - 34  2001年01月

    CiNii

  • Combustion and exhaust gas emission characteristics of a diesel engine dual-fueled with natural gas

    J Kusaka, T Okamoto, Y Daisho, R Kihara, T Saito

    JSAE REVIEW   21 ( 4 ) 489 - 496  2000年10月  [査読有り]

     概要を見る

    This paper deals with a diesel engine dual-fueled with natural gas. This system can achieve a high thermal efficiency at higher loads by utilizing the premixed lean natural gas mixture ignited by pilot-injected diesel fuel. At low loads, however, high THC emission and low thermal efficiency were observed. To resolve these problems, effects of EGR and intake heating with an exhaust to intake heat exchanger on engine performance and exhaust gas emissions were investigated, especially at low loads. In addition, 3-CFD simulations were conducted to analyze the combustion process in the combustion chamber, using the KIVA-3 code. The result indicates that thermal efficiency and THC emission at lower loads can be improved by intake air heating combined with EGR. (C) 2000 Society of Automotive Engineers of Japan, Inc. and Elsevier Science B.V. All rights reserved.

  • 直接噴射式天然ガスデュアルフュエル機関の燃焼・排出ガス特性

    第16回内燃機関シンポジウム講演論文集/自動車技術会,日本機会学会共催   pp.283-288  2000年09月

  • 過濃混合気における多環芳香族及び微粒子の生成過程

    草鹿 仁, 山本 高之, 大聖 泰弘, 斎藤 孟

    自動車技術会論文集   31;3,pp.63-70 ( 3 ) 63 - 69  2000年07月

    CiNii

  • 予混合圧縮着火燃焼と化学反応速度論

    草鹿仁

    JSAE Symposium   No.02-00  2000年01月

    CiNii

  • Combustion and exhaust gas emission characteristics of a diesel engine dual-fueled with natural gas

    Jin Kusaka, Takashi Okamoto, Yasuhiro Daisho, Ryouji Kihara, Takeshi Saito

    JSAE review   21 ( 4 ) 489 - 496  2000年

     概要を見る

    This paper deals with a diesel engine dual-fueled with natural gas. This system can achieve a high thermal efficiency at higher loads by utilizing the premixed lean natural gas mixture ignited by pilot-injected diesel fuel. At low loads, however, high THC emission and low thermal efficiency were observed. To resolve these problems, effects of EGR and intake heating with an exhaust to intake heat exchanger on engine performance and exhaust gas emissions were investigated, especially at low loads. In addition, 3-CFD simulations were conducted to analyze the combustion process in the combustion chamber, using the KIVA-3 code. The result indicates that thermal efficiency and THC emission at lower loads can be improved by intake air heating combined with EGR.

    DOI

    Scopus

    125
    被引用数
    (Scopus)
  • Simulating the homogeneous charge compression ignition process using a detailed kinetic model for n-heptane mixtures

    J. Kusaka, T. Yamamoto, Y. Daisho

    International Journal of Engine Research   1 ( 3 ) 281 - 289  2000年

     概要を見る

    The homogeneous charge compression ignition (HCCI) combustion has been attracting growing attention in recent years due to its potential for simultaneous improvement of exhaust gas emissions and fuel consumption in diesel engines. For practical application of HCCI to internal combustion (IC) engines, precise control of auto-ignition of pre-mixtures during the compression stroke is inevitable. This paper discusses the auto-ignition processes in an HCCI engine operated with n-heptane/air mixtures using a zero-dimensional combustion model including a detailed kinetics. The model proposed is validated first by a comparison between calculated and experimental pressure diagrams, and then the effects of initial charge conditions, compression ratio and excess air ratio on ignition and combustion are investigated. It was found from the parametric study that HCCI combustion of n-heptane/air mixtures is classified into three types of combustion: complete combustion, only low-temperature reaction and misfire, depending on the compression ratio and excess air ratio at which the engine is operated. Finally, the major paths of the HCCI reaction occurring in the engine cylinder were clarified by a sensitivity analysis of chemical reactions involved in the HCCI reaction scheme. © 2000, Institution of Mechanical Engineers. All rights reserved.

    DOI

    Scopus

    29
    被引用数
    (Scopus)
  • 新しいディーゼル燃焼コンセプトと代替燃料の燃焼への応用

    山海堂 エンジンテクノロジー   Vol.05  1999年11月

  • 化学反応速度論を考慮した天然ガス希薄予混合気の自己着火特性(第2報:EGRと過給が着火・燃焼に及ぼす影響)

    自動車技術会1999年秋季大会   No.73-99  1999年09月

  • 天然ガスデュアルフュエル機関の燃焼・排出ガス特性の改善に関する研究

    自動車技術会1999年秋季大会   No.72-99  1999年09月

  • The Effect of Poly-Cyclic Aromatic Hydrocarbons on Particulate Matters in Fuel-Rich Mixture

    The 15th Internal Combustion Engine Symposium(International) in Seoul / JSAE JSME    1999年07月

  • Predicting Homogeneous Charge Compression Ignition Characteristics of Various Hydrocarbons

    KUSAKA J.

    The 15th Internal Combustion Engine Symposium(International) in Seoul / JSAE JSME    1999年07月

    CiNii

  • 直接噴射メタノールディーゼル機関の性能・排出ガス特性の改善(部分予混合気燃焼方式の効果について)

    吉栖博史

    自動車技術会1999年春季大会   No.24-99 ( 99 )  1999年05月

    CiNii

  • 天然ガスの筒内直接噴射によるデュアル・フュエルエンジンの燃焼・排出ガス特性

    草鹿 仁, 池田 明弘, 大聖 泰弘, 木原 良治, 斎藤 孟

    日本機械学会論文集   631;65,p.1083-1088, ( 631 ) 1083 - 1088  1999年03月

     概要を見る

    Combustion and exhaust gas emissions characteristics of natural gas injected into the cylinder of a four-stroke-cycle diesel engine and ignited by pilot injection of liquid diesel fuel have been investigated numerically and experimentally. A 3D-CFD simulation has been conducted to examine the effect of natural gas injection timing on the behavior of natural gas mixture. As a result, the optimum injection timing of natural gas was examined for an engine operating condition, which led to improved THC emissions and thermal efficiency. This can be explained by the fact that the distribution of natural gas at ignition plays an important role in combustion and exhaust gas emissions.

    CiNii

  • 過濃混合気におけるPAH生成に関する化学反応シミュレーション

    学術講演会前刷集/自動車技術会,1998年秋季大会   84-98,pp.5-8,  1998年10月

  • 天然ガス直接噴射デュアルフューエルディーゼルエンジンの燃焼と排出ガス特性

    大聖

    学術講演会前刷集/自動車技術会,1998年秋季大会   86-98,pp.1-5, ( 86 )  1998年10月

    CiNii

  • 化学反応速度論を考慮した天然ガス希薄予混合気の自己着火特性

    大聖

    学術講演会前刷集/自動車技術会,1998年秋季大会   86-98,pp.5-8, ( 86 )  1998年10月

    CiNii

  • Combustion and Exhaust Gas Emissions Characteristics of a Diesel Engine Dual-Fueled with Natural Gas

    KUSAKA J.

    日本機械学会 COMODIA98(The Fourth Internatinal Symposium on Diagnostics and Modeling of Combustion in Internal Combustion Engines)   pp.555-560,  1998年07月

    CiNii

  • CNG自動車用エンジンの新しい燃焼の試みについて

    日本ガス協会,第22回天然ガス自動フォーラム    1998年06月

  • メタノールDIエンジンの着火・燃焼に関する化学反応速度論的検討(第3報 シリンダ内におけるホルムアルデヒド生成過程の解明

    草鹿 仁, 大聖 泰弘, 斉藤 孟

    日本機械学会論文集   622;64,p.1911-1918, ( 622 ) 1911 - 1918  1998年06月

     概要を見る

    An experimental and numerical study of HCHO (Formaldehyde) and other pollutant species formation in the cylinder of a direct-injection diesel engine fueled with methanol has been conducted. Engine tests were carried out under variety of intake conditions including throttling, heating and EGR for the purpose of changing gas composition, temperature in the post-combustion zone. Moreover, the relative importance and influence of individual reactions on HCHO formation and mechanism were assessed with aid of sensitivity analysis.

    CiNii

  • メタノールDIエンジンの着火・燃焼に関する化学反応速度論的検討(第2報 排出ガス生成過程の解析)

    草鹿 仁, 大聖 泰弘, 斉藤 孟

    日本機械学会論文集   622;64,p.1903-1910, ( 622 ) 1903 - 1910  1998年06月

     概要を見る

    A numerical model has been developed for predicting exhaust gas emissions including NO_x HCHO, CH_3OH and other chemical species in a direct injection diesel engine fueled with methanol. In this model, 39 species with related 157 elementary reactions are taken into account. The effects of air excess ratios and load conditions on the exhaust gas emission characteristics were investigated based on this kinetic model. The model can predicts the formation and destruction of chemical species in the combustion process and the formation of formaldehyde and NO_2 during the expansion stroke.

    CiNii

  • Predicting Engine Performance, NOx Emission and Knock Phenomena in a Spark Ignited Natural Gas Engine

    CIMAC, Proeed. of the 22nd CIMAC International Congress on Combustion Engines   5, p.1283-1297,  1998年05月

  • The application of combustion models combined with detailed kinetics for predicting exhaust emissions formation in the cylinder of direct-injection methanol engines

    J Kusaka, Y Daisho, R Kihara, T Saito

    ADVANCES OF ALCOHOL FUELS IN THE WORLD   pp.287-301,   287 - 301  1998年  [査読有り]

     概要を見る

    An experimental and numerical study has been conducted on the emission and reduction of HCHO (formaldehyde) and other pollutants formed in the cylinder of a direct-injection diesel engine fueled by methanol. Engine tests were performed under a variety of intake conditions including throttling, heating, and EGR (exhaust gas recirculation) for the purpose of improving these emissions by changing gas compositions and combustion temperatures in the cylinder. Moreover, a detailed kinetics model was developed and applied to methanol combustion to investigate HCHO formation and the reduction mechanism influenced by associated elementary reactions and in-cylinder mixing.

  • 天然ガスデュアルフュエルディーゼル機関の性能・排出ガス特性の改善

    中山

    1997年秋季大学学術講演会前刷集/自動車技術会   pp.141-144   141 - 144  1997年10月

    CiNii

  • メタノール噴霧のグロー着火と燃焼の可視化

    1997年秋季大会学術講演会前刷集/自動車技術会   pp.137-140  1997年10月

  • メタノールDIエンジンのシリンダ内におけるホルムアルデヒド生成過程の解析(各種吸気条件の影響)

    第14回内燃機関シンポジウム講演論文集/自動車技術会,日本機械学会 共催   pp.229-234  1997年09月

  • Chemical kinetic investigations of ignition and combustion phenomena in a DI diesel engine fueled with methanol (ignition characteristics of methanol mixture)

    J Kusaka, Y Daisho, T Saito

    JSME INTERNATIONAL JOURNAL SERIES B-FLUIDS AND THERMAL ENGINEERING   40 ( 3 ) 432 - 438  1997年08月  [査読有り]

     概要を見る

    A methanol-fueled direct-injection diesel engine with a glow-assisted ignition system tends to suffer from poor ignitability under low load conditions. Chemical delay phenomena associated with methanol mixture ignition were investigated to improve ignitability. The effects of the vaporization heat of liquid methanol, the surface temperature of the glow-plug, the heat created by the glow-plug and the Oz excess ratio of methanol-air mixtures on the ignition characteristics were examined. Our numerical model considers these parameters, and a detailed chemical kinetic scheme, including 39 chemical species and 157 elementary reactions, was used to predict the delay in methanol mixture ignition.

  • メタノールDIエンジンにおける有害排出ガス生成過程の解析(吸気条件の影響)

    第74期通常総会講演会講演論文集/日本機械学会   pp.150-151  1997年03月

  • Simulating exhaust emissions characteristics and their improvements in a glow-assisted di methanol engine using combustion models combined with detailed kinetics

    Jin Kusaka, Yasuhiro Daisho, Ryoji Kihara, Takeshi Saito

    SAE Technical Papers   SAE971598  1997年

     概要を見る

    An experimental and numerical study has been conducted on the emission and reduction of HCHO (formaldehyde) and other pollutants formed in the cylinder of a direct-injection diesel engine fueled by methanol. Engine tests were performed under a variety of intake conditions including throttling, heating, and EGR (exhaust gas recirculation) for the purpose of improving these emissions by changing gas compositions and combustion temperatures in the cylinder. Moreover, a detailed kinetics model was developed and applied to methanol combustion to investigate HCHO formation and the reduction mechanism influenced by associated elementary reactions and in-cylinder mixing. © 1997 Society of Automotive Engineers, Inc.

    DOI

    Scopus

  • Simulating exhaust emissions characteristics and their improvements in a glow-assisted di methanol engine using combustion models combined with detailed kinetics

    Jin Kusaka, Yasuhiro Daisho, Ryoji Kihara, Takeshi Saito

    SAE Technical Papers   SP-1276 pp.127-139  1997年

     概要を見る

    An experimental and numerical study has been conducted on the emission and reduction of HCHO (formaldehyde) and other pollutants formed in the cylinder of a direct-injection diesel engine fueled by methanol. Engine tests were performed under a variety of intake conditions including throttling, heating, and EGR (exhaust gas recirculation) for the purpose of improving these emissions by changing gas compositions and combustion temperatures in the cylinder. Moreover, a detailed kinetics model was developed and applied to methanol combustion to investigate HCHO formation and the reduction mechanism influenced by associated elementary reactions and in-cylinder mixing. © 1997 Society of Automotive Engineers, Inc.

    DOI

    Scopus

  • グローアシストメタノールDI機関の性能・排気特性−スリット噴射ノズルによる燃焼改善

    草鹿 仁, 大聖 泰弘, 斎藤 孟, 木原 良治

    自動車技術会論文集/自動車技術会   26-4 ( 4 ) 75 - 80  1995年10月

    CiNii

  • グローアシストメタノールDI機関の燃焼・排気特性

    草鹿仁

    秋季大会学術講演前刷集/自動車技術会   954  1995年09月

    CiNii

  • メタノール混合気の着火に関する化学反応速度論的検討

    第73期全国大会講演論文集/日本機械学会   3  1995年09月

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共同研究・競争的資金等の研究課題

  • インテリジェントエコービーグルに関する研究

    文部科学省 

    研究期間:

    1997年
    -
    2001年
     

Misc

  • F131 Numerical and Experimental Studies on Flame Propagation of Iso-octane in a Constant Volume Chamber

    Sok Ratnak, Kusaka Jin

    動力・エネルギー技術の最前線講演論文集 : シンポジウム   2014 ( 19 ) 173 - 174  2014年06月

     概要を見る

    This paper describes experimental and numerical studies of premixed flame propagation in a constant volume chamber (CVC). A mixture of iso-octane and air is tested at initial pressure and temperature of 3 bar and 420K, respectively. Flame speed visualizations are recorded using high speed video camera at frame speed of 2000 frames/sec. The numerical simulation consist of one dimensional premixed laminar flame code coupled with computational fluid dynamic (CFD) study. The G-equation (level-set method) flame propagation model is used in the CFD calculation with detailed chemistry of iso-octane which consists of 56 chemical species and 437 reactions. Comparison of flame front displacement is reported in this study. Calculation results of pressure-time history show good agreements with that of experiment.

    CiNii

  • エンジンの応答曲面モデルと制御パラメータ最適化手法の開発

    小川 雅俊, 鈴木 泰政, 大貝 晴俊, 草鹿 仁

    計測自動制御学会論文集 = Transactions of the Society of Instrument and Control Engineers   47 ( 10 ) 501 - 510  2011年10月

    CiNii

  • エンジン制御教育システムの開発

    大貝晴俊, 小川雅俊, Musighcahi Marth, 呉冬梅, 焦鵬飛, 草鹿仁

    第52回システム制御情報学会研究発表会講演論文集     451 - 452  2008年

    DOI

産業財産権

  • エンジンの燃焼室構造

    5613730

    中山 竜太, 草鹿 仁

    特許権

  • エンジンの燃焼室構造

    5564538

    中山 竜太, 草鹿 仁

    特許権

  • エンジン制御パラメータ適合化装置及びプログラム

    大貝 晴俊, 小川 雅俊, 草鹿 仁

    特許権

  • 応答曲面モデル構築装置及びプログラム

    大貝 晴俊, 小川 雅俊, 草鹿 仁

    特許権

  • エンジンの排気浄化装置

    5680060

    草鹿 仁, 加藤 秀朗, 野竹 康正

    特許権

  • エンジンの燃焼室構造

    草鹿 仁, 中山 竜太

    特許権

  • エンジンの燃焼室構造

    5178491

    草鹿 仁, 中山 竜太

    特許権

  • 排気浄化装置及び排気浄化方法

    草鹿 仁, 免出 武之, 高田 圭

    特許権

  • ディーゼル排ガス処理装置およびディーゼル排ガスの処理方法

    草鹿 仁, 神長 隆史

    特許権

  • 多段噴射式機構を有するディーゼルエンジン用燃料油組成物

    4930820

    草鹿 仁

    特許権

  • 多段噴射機構を有するディーゼルエンジン用燃料油及び多段噴射機構を有するディーゼルエンジン

    草鹿 仁

    特許権

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その他

  • 業績については、草鹿研究室ホームページをご参照ください。

 

現在担当している科目

▼全件表示

 

特別研究期間制度(学内資金)

  • ディーゼル燃焼に関する研究

    2005年08月
    -
    2006年07月

    スウェーデン   Chalmers University of Technology

他学部・他研究科等兼任情報

  • 理工学術院   大学院情報生産システム研究科

  • 理工学術院   創造理工学部

  • 理工学術院   大学院創造理工学研究科

  • 附属機関・学校   グローバルエデュケーションセンター

学内研究所・附属機関兼任歴

  • 2022年
    -
    2024年

    理工学術院総合研究所   兼任研究員

  • 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

  • 2020年
    -
    2024年

    自動車用モデルベース制御研究所   プロジェクト研究所所長

特定課題制度(学内資金)

  • 固体高分子型燃料電池の内部挙動解明に関する基礎研究

    2004年  

     概要を見る

    固体高分子形燃料電池の内部物質輸送現象を解明するため,反応面を絶縁体により分割した分割電極セルを用いた電流密度および抵抗分布計測を行い,反応ガスの相対湿度,ガス流れ方向(コフロー,カウンターフロー),ガス拡散層仕様(カーボンクロス,カーボンペーパー)がセル性能へ与える影響を調査した.また,物質輸送と電気化学反応を連成させた単相2次元数値モデルを構築し,実験結果との比較検討を行った.低加湿運転時には,カウンターフローによるセル内の水分循環効果を利用することで,同加湿条件のコフローに比べ,反応面全域の抵抗を低く抑えることでき,セル電圧を確保できることが示された.また,拡散性が低いガス拡散層を用いた場合には,フラッディング特性が変化することが明らかになった.これらの検討より,電解質膜内の水分分布を予測することが可能になり,各種運転条件における輸送現象を解析し,設計指針を得ることができた.また,従来の研究において,数値モデルに用いる供試電解質膜の物質輸送特性(含水率特性,水の拡散係数)は,いくつかの文献値を参照するに留まっていたが,これらの値はセル内の水分移動特性に対し,大きな寄与度をもつことが知られている.そこで,鏡面冷却式露点計を用いて供試膜の物質輸送物性を計測し,その計測結果を数値モデルに組み込み,不確定なパラメータを減らすことでモデルの精度を向上させた.さらに,露点計を用いた発電中の極間の水分移動量計測を行い,実験と計算の結果において良好な一致が得られ,数値モデルの妥当性を確認するとともに,セル設計ツールとしての有用性を検証することができた.

  • 固体高分子形燃料電池における輸送現象解明に関する実験及び数値モデルの構築

    2004年  

     概要を見る

    固体高分子形燃料電池の内部物質輸送現象を詳細に調査するため,小型単セル(均一場セル)に対して大流量のガスを供給することで,反応ガスの消費および水分の生成の影響を無視することができる均一な反応場を形成し,物質輸送現象に起因する低加湿運転時の分極現象について解析を行った.また,実験結果を理解するために触媒層内の物質輸送現象をアグロマレイトモデルにより記述した数値モデルを構築し,比較検討を行った.これらの検討から低加湿運転時のセル性能低下要因は,電解質膜のプロトン伝導性低下のみならず,触媒層内電解質のプロトン伝導性低下および反応ガスの溶解,拡散性低下の複合現象であることが明らかになり,それらの中でもとりわけ,電解質膜および触媒層内電解質のプロトン伝導性低下の影響度が大きいことが示された. さらにカソードの流路形状がセル性能に与える影響を調査するために,ピッチを固定し,ウェブ(ガス流路部)とリブ(集電部)の比率や流路形状(ストレート,インターデジテイティッド)を変化させ,性能試験を行った.高加湿運転時には,リブ下の反応面に高い酸素濃度を形成できるウェブ幅の広いセルや対流効果により液水の滞留を抑止しつつ高い酸素濃度を保つことができるIDセルにおいて高いセル性能が得られることが明らかになり,低加湿運転時にはリブ下の乾燥を抑止することができるウェブ幅の広いセルにおいて高いセル性能が得られることが示された.このように,フラッディングと乾燥の抑止性はトレードオフの関係にあり,運転条件および流路における位置(上下流)に適応した流路設計がセル性能を確保するためには不可欠であることが示された

  • 化学反応速度論を考慮した燃焼モデルの構築と各種燃料の燃焼過程の素反応機構の調査

    1999年  

     概要を見る

    (1) 燃焼素反応文献調査:燃焼反応機構が多数掲載されている学術論文誌 'Combustion and flame'、'Symposium(International) on combustion'、 ' Combustion science and technology'を中心に、1970年から各種燃料の燃焼素反応及び燃焼過程における有害排出物質の生成機構を調査し、データーベースを作成した。(2) エンジンを用いた燃焼実験:申請者らが現有するエンジン実験装置を用いて、天然ガス及び軽油と類似した燃焼特性を有するノルマルヘプタンを対象に予混合圧縮着火特性を調査した。 (3) 応速度論を考慮した燃焼モデルの構築:天然ガスの代表組成はメタン88%、エタン5%、プロパン5%及びブタン2%であることから、燃焼スキームにはC4のケミストリーが必要となる。(1)で調査した素反応機構により得られる各化学種の速度方程式をエネルギー方程式と組み合わせ数値的に解くことで、ショックチューブ、急速圧縮膨張装置などの実験結果と着火遅れ時間を比較した。その結果、「S. Kojima," Detailed Modeling of n-Butane Auto-ignition chemistry", Combustion and Flame Vol.99, 1994 」が各種実験の結果を合理的に説明できることが分かった。そこで、これらにサーマルNOとプロンプトNOの生成反応を加えた反応スキーム(素反応数508、化学種151種)を用いてエンジンにおける燃焼をシミュレートした。この結果、計算により得られたシリンダ内圧力線図は、実験から採取された圧力線図をよく再現し、実際のエンジンの燃焼を記述することが可能であることが明らかになった。また、計算によって得られたNOの生成量は実験結果と合致することから、本燃焼モデルを用いて低NOかつ高効率となる運転条件を予測した。 同様の計算手法を用い、軽油に近い圧縮着火特性を有するノルマルヘプタン(C7H16)について計算を行った。反応スキームには、「H. J. Curran, P.Gaffuri, W. J. Pitz, and C.K. Westbrook, "A Comprehensive Modeling study of n-Heptane Oxidation", Combustion and Flame,: Vol.114, pp.49-177, 1998」をベースに、前述したN系の反応及び、ディーゼルエンジンから排出される微粒子の前駆物質と考えられるPAH( Poly-cyclic Aromatic Hydrocarbon) の生成を記述した素反応を組み入れ、燃焼及び有害排出物質の生成過程をシミュレートした。その結果、実験で確認されたノルマルヘプタンの2段燃焼(低温酸化、高温酸化)特性をよく再現できることに加え、PAHの生成特性も実験結果とよい相関が得られた。 以上、基礎燃焼化学分野の論文を調査し、それを用いて各化学種に関する速度方程式とエネルギー方程式を組み合わせ、系の温度、圧力及び各化学種の濃度履歴を算出した。さらに、NO、PAHの生成量、さらに圧力履歴を実験結果と比較した結果良い一致が得られたことから、このような計算手法は妥当であり、今後もエンジンの燃焼特性、有害排出物質の生成特性を調査する上で有用であると判断される。