Influence of various oxygenated fuel additives on performance and emissions of a biodiesel fuelled engine: An experimental study

In the present study, an effort has been made to use higher biodiesel blends effectively in compression ignition engine by using low viscosity oxygenated fuel additives. Experimental investigation is carried out to select the best possible additive to the neat biodiesel in order to run the engine using higher blends. It is seen that performance of the engine has been improved by the addition of additives when compared to neat biodiesel operation. The B30 (30% biodiesel and 68% diesel by volume) biodiesel fuel with 2% diethyl ether additive shows higher brake thermal efficiency compared to B30 biodiesel with acetone and butanol additives. The value of brake thermal efficiency is at par with neat B20 operation. The peak cylinder pressure is higher for B30 with oxygenated additives compared to neat B30 fuel operation. For B30 biodiesel with 2% diethyl ether additive, highest peak cylinder pressure is noticed and this value is nearly close to neat biodiesel (B20) operation. It is also observed that the addition of oxygenated fuel additives to neat biodiesel fuel reduce the tail pipe emissions. Carbon monoxide and hydrocarbon emissions are reduced for oxygenated additive blended fuels. The maximum reduction was observed for the B30 biodiesel - diethyl ether combination.