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Comparative Performance of Diesel Engine Operating on Ethanol, Petrol &Karanja Oil Blends

Rakesh Vishwakarma, A.C. Tiwari, Nitin Shrivastava

The continuous increasing demand for energy and the decreasing petroleum resources has led to the search for alternativefuel which is renewable and sustainable. Vegetables oils are simplest route of biofuel utilization in direct injection compression ignition (DICI) engines however several operational and durability problems are encountered while using straight vegetable oils in CI engines due to their high viscosity and low volatility. Reduction of viscosity by blending or exhaust gas heating leads to savings in chemical processing cost incurred on trans-esterification. This article presents the comparative bench testing results of a four stroke, four cylinder, direct injection, unmodified, naturally aspirated diesel engine operating on karanja oil (KO) and its 2.5 vol%, 5 vol%, 7.5 vol% and 10 vol% blends with ethanol (EKO), petrol (PKO) and both improving agents applied in equal proportions as 50:50 vol% (EPKO).The purpose of this research is to examine the effects of KO inclusion in Diesel fuel on the brake specific fuel consumption(bsfc) of a Diesel engine, its brake thermal efficiency, brakemean effective pressure, mechanical efficiency and volumetric efficiency. The brake specific fuel consumption at maximum torque (517 g/kW h) for EPKOis higher by 13.8% relative to Diesel fuel. It is difficult to determine the KO concentration in Diesel fuel that could be recognized as equally good for all loads and speeds. The maximum brake thermal efficiency varies from 0.157to 0.181 for EPKO and from 0.182 to 0.198 for Diesel fuel. Addition into KO of ethanol and petrol its viscosity at ambient temperature of diminishes to a great extent and for blend EPKO10 is almost equal to diesel.