Simulation Study of Combustion Characteristics of Diesel-Ethanol-Palm Oil Methyl Ester Blends in Diesel Engine

Norhidayah Mat Taib; Mohd Radzi Abu Mansor; Wan Mohd Faizal Wan Mahmood; Nik Rosli  Abdullah

Authors

Norhidayah Mat Taib Department of Mechanical and Materials Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor
Mohd Radzi Abu Mansor Department of Mechanical and Materials Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor
Wan Mohd Faizal Wan Mahmood Department of Mechanical and Materials Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor
Nik Rosli Abdullah Faculty of Mechanical Engineering, UniversitiTeknologi Mara (UiTM), Shah Alam, Selangor

Keywords:

Palm oil Methyl Ester , Combustion Characteristics , Heat Release Rate, Ignition

Abstract

Diesel-ethanol-palm methyl ester (PME) blends are believed to be able to improve the combustion characteristics since diesel, ethanol, and PME have different fuel characteristics. This paper is aimed to study the combustion characteristics of pure diesel and diesel-ethanol-PME blends with different compositions through simulation works and to estimate the best fuel composition that can be used in real engine applications. A simulation work was conducted using seven different diesel-ethanol-PME blends for a combustion based on a compression ignition Yanmar TF90 engine parameter by using a CONVERGE CFD software. Seven diesel-ethanol-PME blends (10 vol% to 40 vol%) PME were mixed in ethanol together with 50 vol% diesel fuel operated at 1600 RPM. High PME percentage increased the heat release rate (HRR). However, due to non-uniform chemical energy release from the reaction, the blends of 25 vol% PME with 25 vol% ethanol blends released the highest HRR. A high percentage of ethanol reduced the temperature and increased the heat release. From the cumulative heat release, ignition delay occurred for blends that had more than 15 vol% ethanol. In conclusion, blending ethanol and PME in diesel increased the combustion heat release rate to have better engine efficiency. However, the blend that contained more than 35 vol% ethanol was not suitable to be used in direct injection compressed ignition engine without any modification since the temperature and HRR of the blends is very low.