Environmentally Efficient Biodiesel Blend of Jatropha Oil and Rubber Seed Oil as an Alternative Fuel for a Direct Injection Diesel Engine for Reducing Engine Emission

The vegetable oils named as biodiesel are being directly used as alternative fuel to run the compression ignition (CI) engines. Due to high viscosity of bio fuel, it does not completely burn inside the combustion chamber and it produces high smoke and increased Nitric oxide emission. In this experimental study, a dual bio fuel (jatropha oil and rubber seed oil) blends mixed with the pure diesel has been charged in to a single cylinder four stroke diesel engine to analyse the performance and emission characteristics of the engine. The engine was running at 1500 rpm and the fuel injection pressure of 240 bar was maintained to a constant value instead of the normal pressure of 220 bar. The biodiesel fuels at different propositions were prepared by volume basis and named such as B20, B40, B60, B80 and B100. The test engine was operated at different load conditions of 0%, 25%, 50%, 75% and100% at the rated power of 4.4kW. The results obtained shows that the specific fuel consumption was lowered and the brake thermal efficiency was increased for B20 blend at all load conditions. From the emission analysis, the characteristics such as carbon monoxide (CO), hydro carbons (HC) and nitric oxide (NOx) were decreased for the blend B20, and the carbon dioxide (CO2) emission was increased. Using B100 at full load condition emission was increased considerably. In this study, for the increased injection pressure, the B20 blend gave the best result compared to other biodiesel proportions at all engine loads.