INFLUENCE OF INJECTION TIMING AND COMPRESSION RATIO ON PERFORMANCE, EMISSION AND COMBUSTION CHARACTERISTICS OF JATROPHA METHYL ESTER OPERATED DI DIESEL ENGINE

Diesel fuel has a limited resource and concerns over environmental pollution are leading to the use of 'bio-origin fuels' as they are renewable and environmentally benign. Jatropha methyl ester, an esterified biofuel, has an excellent cetane number and a reasonable calorific value. It closely resembles the behaviour of diesel. However, being a fuel of different origin, the standard design limits of a diesel engine is not suitable for Jatropha methyl ester. Therefore, in this work, operational parameters are studied to find out the optimum performance of Jatropha methyl ester run diesel engine. The parameters varied are the compression ratio (CR) and injection timing (IT) along with load in a diesel engine. This work targets finding the effects of the engine operating parameters on the performance of the engine with regard to specific fuel consumption (SFC) and brake thermal efficiency (BTHE) with Jatropha methyl ester(J20) as fuel. Further exhaust emissions of the engine for the above conditions are also studied.Thus J20 can be effectively used in a diesel engine without any modification. At compression ratio of 19.5 along with injection timing of 30 degrees bTDC (before top dead centre) will give better performance and lower emission which is very close to diesel. Comparison of performance and emission was done for different values of compression ratio along with injection timing to find the best possible combination for operating engine with J20. It is found that the combined increase of compression ratio and injection timing increases the BTE and reduces SFC while having lower emissions. Diesel (20%) saved, will greatly meet the demand of fuel in railways.