Comparative Studies on Exhaust Emissions and Combustion Characteristics of Tobacco Seed Oil in Crude form and Biodiesel form in Direct Injection Diesel Engine

Experiments were conducted to determine exhaust emissions and combustion characteristics of a conventional diesel engine with different operating conditions [normal temperature and pre-heated temperature] of tobacco seed oil in crude form and in biodiesel form with varied injection timing and injector opening pressure. Exhaust emissions [smoke and oxides of nitrogen] and combustion characteristics [peak pressure, time of occurrence of peak pressure and maximum rate of pressure] were determined at peak load operation of the engine fuelled with diesel, crude tobacco seed oil and tobacco seed oil based biodiesel. Comparative studies on exhaust emissions and combustion characteristics were made between diesel, crude vegetable oil and biodiesel operation on diesel engine with varied engine parameters. Smoke levels decreased and NOx levels increased with biodiesel operation. Exhaust emissions and combustion characteristics improved with increase of injector opening pressure, advanced injection timing and preheating of vegetable oil(s).