Investigations on diesel engine performance based on jatropha, karanja and neem biodiesels

Owing to the steep rise in demand for petroleum fuel and the depletion of the petroleum reserves, there is an intensive search for alternative fuels in the world. Non-edible oils with low viscosity can be a good alternative sustainable fuel for compression ignition engines. Transesterification of oils is a process which brings viscosity into a range equivalent to that of diesel fuel. In this study, three non-edible oils, namely, jatropha, karanja and neem oils are transesterified and these transesterified oils (biodiesels)have been tested in a four-stroke compression engine. Test results obtained have been analysed and compared for engine performance evaluation with respect to diesel fuel. This study indicates that methyl esters of jatropha, karanja and neem oils can be a good substitute for diesel fuel in compression ignition engine without any engine modification. Brake specific fuel consumption and brake specific energy consumption are slightly higher compared to diesel fuel for all operating ranges of the engine. Small variation in the exhaust gas temperature and thermal efficiency are observed while the engine is run on four different fuels.