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Improvement of Fuel Consumption of Neat Biofuel Diesel Engine with Reduced Injection Driving Torque

SAE International Journal of Engines

Kogakuin Univ.-Junya Tanaka, Koji Korematsu
Meiji Univ.-Taizo Shimada, Mitsuo Notomi
  • Journal Article
  • 2013-01-2475
Published 2013-09-24 by SAE International in United States
In recent years, trans-esterified vegetable oils have been widely applied to diesel engine in order to suppress greenhouse gas emissions. However, “neat” vegetable oils are expected to be directly used to resolve some difficulties faced in their use, such high viscosity and slightly high fuel consumption. In this study neat linseed oil has been investigated as a neat vegetable oil. It was found to show higher fuel consumption than diesel fuel, however at the same time it showed lower indicated fuel consumption than diesel fuel. These results suggest some increase in engine friction loss in a neat biofuel diesel engine. Studies have been extensively investigated the difference in friction loss and a newly developed “improved deceleration method” has been applied. Doing so confirmed the higher fuel injection driving torque caused by the higher viscosity of neat linseed oil relative to diesel fuel and the effect of the enlarged inner diameter of the fuel injection pipe on reducing the engine friction of high-viscosity fuel. Finally, a neat linseed oil engine with an optimized fuel injection pipe…
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On Knocking Generated in Crevice Channel of SI Engine

Kogakuin Univ.-Taiki Tokudome, Koji Korematsu
  • Technical Paper
  • 2012-08-0139
Published 2012-05-23 by Society of Automotive Engineers of Japan in Japan
Knock in crevice is found by the experiments using the constant volume vessels have an additional small chamber which is simulated top land crevice of spark ignition engines. We found two types of knocking. The first type of knocking generated in crevice is induced by the knocking in main chamber. The second type is the starting point of knocking is inside of crevice. The pressure wave in the crevice is strong whose has larger amplitude and higher frequency than the pressure wave in the main chamber. This means the potential of crevice knock has infliction of stronger damage on a crevice. It should be noted the pressure wave of both in the main chamber and in the crevice is not differs and no one found before.

Measurement of Instantaneous Pressure in Model Channel of Injection Systems of DME-Fueled Engines

Kogakuin Univ.-Hiroyuki Umeyama, Koji Korematsu, Junya Tanaka, Yukihiro Ohkubo
  • Technical Paper
  • 2008-08-0502
Published 2008-10-22 by Society of Automotive Engineers of Japan in Japan
The unstable operation of the engine is found, when the pressure in the injection pipe of the DME (CH3OCH3) engine is lower than the saturation pressure of DME. This fact means that the flow of DME is choked by the bubbles which are generated by the cavitations and the injection rate of DME to the combustion chamber is too small to run the engine smoothly. In order to prevent the unstable operation of the engine, the pressure of DME in the injection pipe is always over its saturation pressure. The flow generated by the rapid movement of the solenoid valve simulates the injection system of DME-fueled diesel engine. Experimental results conducted that the instantaneous pressure in the pipe depends on the wave propagation and the vibration of solenoid valve. The measured pressure in the pipe agrees with the calculated value by the one-dimensional unsteady DME flow model.

Study on Unstable Operation of the Diesel Engine Fueled by DME Due to the Cavitations in the Injection System

Kogakuin Univ.-Tsuyoshi Onodera, Koji Korematsu, Junya Tanaka
Suzuki-Kensuke Hamada
  • Technical Paper
  • 2006-08-0506
Published 2006-09-27 by Society of Automotive Engineers of Japan in Japan
The measured pressure in the injection pipe of the DME engine is lower than the saturation pressure of DME, when the unstable operation of the engine appears. This fact means that the flow of DME is obstructed by the bubbles which arose by the cavitations and the injection rate of DME to the combustion chamber is insufficient. The generation points of the cavitations can be estimated by the mathematical model of the flow in the injection system. In order to avoid the instability of the engine due to the cavitations, the DME pressure of the injection system is always kept over the saturation pressure.

Electric Energy Consumption During Cranking Process of Internal Combustion Engines

Kogakuin Univ.-Takahiro Miyashita, Koji Korematsu, Junya Tanaka
TGK-Moritaka Matsuura
  • Technical Paper
  • 2006-08-0619
Published 2006-09-27 by Society of Automotive Engineers of Japan in Japan
The idling stop campaign is widely accepted and begins to expand to short-time idling stop, i.e., to the vehicles stopped by the traffic signal. An arguing point of the short-time idling stop is "Is which high value the re-starting energy of the engine or the fuel saving due to stop of the engine?" The re-starting energy of the engine is classified into the electric energy of the starting motor and the fuel energy for the acceleration of the engine. In this paper the electric energy of the starting motor supplied by the battery is measured for three test engines. It should be noted that the electric energy used for the motion of the crankshaft and compression of the gas in the cylinder is not wasted.

Fuel Consumption Improvement of Vehicles by Idling Stop

Kogakuin University, Japan-Moritaka Matsuura, Koji Korematsu, Junya Tanaka
Published 2004-06-08 by SAE International in United States
Investigation has been carried out for the effect of the idling stop for a short time when stopping by the traffic signal. The amount of the fuel consumption by the idling stop is formulated by the following equations. Where Fs Saved fuel consumption (cc), I Fuel consumption during idling (cc/s), Tis Period during the idling stop (s), S2 Additional fuel consumption by restarting the engine (cc), S3 Energy consumption at the battery for starting, in fuel consumption equivalence (cc), Nis Frequency of idling stop.
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Potential of Rapeseed Oil as Diesel Engine Fuel

Dept. of Mechanical Engineering Kogakuin Univ. Tokyo-Koji Korematsu, Junya Tanaka
Graduate School of Kogakuin Univ. Tokyo-Kensuke Nishi
Published 2004-06-08 by SAE International in United States
In order to achieve a sustainable society, vegetable oil derived from solar energy is a major topic of interest. Vegetable oils are can potentially be utilized as fuel in applications such as engines, gas turbines, furnaces, boilers and steam power plants. In this paper, rapeseed oil as a fuel for diesel engine was studied. There are seven refinement processes that improve the quality of the oil because the rapeseed oil is mainly produced for food. Rapeseed oil is produced from the raw material through compression, solvent extraction, degumming, deoxidation, bleaching, deodorization and a final-refinement process. However, all of these refinement processes are not necessary if the oil is to be used for diesel fuel. The performance of the engines operated by the tested fuels, which were extracted at the end of each of the seven refinement stages, was investigated.The major findings of this study are as follows. The brake thermal efficiency is unrelated to the refinement process and is almost equal to the performance with diesel fuel. Therefore, it is obvious that the tendency of…
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Study on wear of piston rings in diesel engines with exhaust gas recirculation

Kogakuin Univ.-Tokuro Sato, Hideki Saito, Koji Korematsu, Junya Tanaka
  • Technical Paper
  • 2000-08-0012
Published 2000-10-17 by Society of Automotive Engineers of Japan in Japan
The wear of piston rings in the diesel engines with EGR system is studied experimentally. In order to clarify the effect of particulate matter (PM) on the wear, the wear of the piston rings in the test engine is measured (1) when the insoluble in the lubricating oil is removed by the oil filters, (2) when PM in the recirculated gas is removed by the ceramic gas filter, (3) when the carbon particles is added in the lubricating oil.The experimental results are discussed with the measured time history of kinematic viscosity, total base number, total acid number, ZDTP survival rate, and carbon residual content and its particle size in the motor oil.

Study on Intelligent Idling Stop System

1),2) Department of Mechanical Engineering of Kogakuin University. 2665-1, Nakanomachi.Hachioji-shi, Tokyo, 192-0015, Japan 3) Nissan Motor CO., LTD-Kazuhiro Tanaka, Koji Korematsu, Yoshitsugu Yamazaki
  • Technical Paper
  • 2000-05-0365
Published 2000-06-12 by Society of Automotive Engineers of Korea in South Korea
The “idling stop” of the vehicle, which is defined as no rotation of the engine when it stops, theoretically brings to reduce the fuel consumption (i.e. carbon dioxide) and the exhaust emissions. However, the idling stop practically has weak points as follows: 1. When the engine is restarted, much fuel is consumed. 2. When the engine is restarted, much the exhaust emissions are discharged. 3. While various electric devices work, the load of the battery is high. 4. The deterioration of the lubricating oil proceeds due to repeating start and stop.In order to overcome the above weak points the authors propose the new system called IISS.

Electric Vehicle for Newspaper Delivery-Second Report

Kogakuin Univ.-Shozo Harada, Koji Korematsu
Meitec Corp.-Kazuya Numaguchi
  • Technical Paper
  • 968035
Published 1996-05-15 by Society of Automotive Engineers of Japan in Japan
Noise pollution in the early morning by newspaper delivery motorcycles is sometimes pointed out. In order to preserve the clean and quietness of environment in the early morning, the electric vehicles for newspaper delivery must be introduced. Firstly, in this paper we demonstrate that the electric vehicle with full charge has enough range to deliver the newspaper under real conditions. Secondly, it is concluded that the maximum sound level of the electric vehicle is lower than the motorcycle operated by internal combustion engine.