Performance and emission studies on biodiesel-liquefied petroleum gas dual fuel engine with exhaust gas recirculation

Biodiesel is an alternative fuel to diesel derived from vegetable oils by transesterification process. It can be used in diesel engines with/without any modification in the engine system. Biodiesel engines emit slightly higher NO(x) emissions, as compared to that of diesel engines, as higher cylinder temperatures achieved during combustion. To reduce the NO(x) emissions a small percentage of exhaust gases recirculated into the cylinder in dual mode operation. For the improvement of power, liquefied petroleum gas (LPG) was supplied along with fresh air in dual mode operation. This article describes experimental investigation on performance and emission characteristics of single cylinder, indirect diesel engine fueled with biodiesel-diesel blend and LPG in dual fuel mode operation with exhaust gas recirculation (EGR). Recirculation of exhaust gases into the engine decreases the combustion chamber temperatures and marginal improvement in thermal efficiency was observed with EGR. However, reduction in air flow into the engine slightly increases carbon monoxide and hydrocarbon emissions. The exhaust gas temperature of dual fuel engine with EGR is lower than that of engine without EGR. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3302019]