Performance and emission analysis of DI diesel engine fuelled with methyl esters of beef tallow and diesel blends

This paper evaluates the possibility of using methyl esters from animal fats as an alternative fuel for diesel. Biodiesel is an alternative fuel produced from different kinds of vegetable oils and animal fats. It is an oxygenated, non-toxic, sulfur free, biodegradable and renewable fuel that can be used in diesel engines without any significant modifications. Performance and exhaust emissions of direct injection diesel engine have been experimentally investigated with methyl esters of beef tallow as neat biodiesel (B100) and its blend (B5, B25, B50 and B75) with diesel fuel. Engine performance parameters namely brake power, brake specific fuel consumption, brake thermal efficiency and exhaust emissions of CO, HC, NOx, and smoke density were determined for different loading conditions and at constant engine speed of 1500 rpm. The test result indicates that there is a slight decrease in brake thermal efficiency and increase in specific fuel consumption for all the blended fuels when compared to that of diesel fuel. The drastic reduction in carbon monoxide, unburned hydrocarbon and smoke density were recorded for all the blended fuels as well as with neat biodiescl. However, in the case of oxides of nitrogen, there is a slight increase for all the blended fuels and with neat biodiesel when compared to diesel fuel. On the whole, methyl esters of beef tallow and its blends with diesel fuel can be used as an alternative fuel for diesel in direct injection diesel engines without any significant engine modification. (C) 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Noonil Islam Centre for Higher Education