An Experimental Investigation on Performance, Combustion and Emission Characteristics of a Low Heat Rejection Engine Using Diesel and Diethyl Ether Blends

This research work investigates the performance, combustion and emission characteristics of a low heat rejection engine operated on diesel and diethyl ether blends. The combustion chamber walls of the diesel engine insulated by ceramic material were referred to as low heat rejection (LHR) engine. In the LHR engine, an improvement in fuel economy would be obtained by recovering the waste heat rejected to the cooling system as useful work. Initially, the diesel fuel was tested in the conventional engine as a baseline reading for comparison. Then the engine was insulated by coating the engine components of the piston crown and the cylinder liner with aluminum titanate using plasma spray method. In this work, the experiments are conducted using diesel and diethyl ether blends in a conventional and low heat rejection engine at constant speed condition. The experimental results indicate that the brake thermal efficiency increases with increased percentage of diethyl ether in the blends. The maximum brake thermal efficiency was found to be 33.24% for LHR engine using diesel-diethyl ether blend (Diesel 85% & Diethyl ether 15% by volume) at full load condition. The emissions of carbon monoxide and hydrocarbon are decreased due to better combustion characteristics and higher NO_x emissions are observed with low heat rejection engine (LHR) compared to the conventional engine using diesel and blended fuels.