Experimental investigations of a low heat rejection (LHR) engine powered with Mahua oil methyl ester (MOME) with exhaust gas recirculation (EGR)

Abstract

ABSTRACTContinued effort has been made by several researchers to reduce the dependency on fossil fuels by using suitable alternative and renewable fuels such as biodiesels for energy harvesting and vehicular applications. Alternative fuels can partially or totally replace fossil fuels in diesel engine applications and address tailpipe emissions as well, which lead to global warming. Performance of compression ignition (CI) engines fueled with biodiesel can be further improved with low heat rejection engine facility by suitably utilizing the heat rejected from the engine and thereby improving the thermal efficiency. Present work combustion surfaces of piston, valves and cylinder head were coated with ceramic material, making the engine fully adiabatic, also known as a low heat rejection (LHR) engine. Experiments were conducted on an LHR engine using diesel and Mahua oil methyl ester (MOME) to determine its performance with and without exhaust gas recirculation (EGR). An attempt has been made to compare the performance and emissions characteristics of a CI engine operated on MOME with and without ceramic coating, and the effect of an EGR system developed in-house. EGR was varied from 0 to 20% in steps of 5%. The LHR engine yielded increased brake thermal efficiency (BTE), reduced emissions of smoke, HC[Hydro Carbon] and CO, and increased NOx with MOME when compared to an uncoated engine. As EGR rate increased the BTE and NOx were slightly reduced whereas the HC, CO and smoke were increased. At 10% EGR, 25.96% BTE, 59 HSU smoke, 46 ppm HC, 0.163% volume CO and 1048 ppm NOx were reported.