Experimental investigation to study the effects of using hot and partially cold EGR in direct injection diesel engine

Abstract

Major exhaust emissions from diesel engines are CO, CO2, PM, UHC and NOx, of which NOx is one of the most harmful. A number of techniques have been utilized to control NOx emissions and exhaust gas recirculation (EGR) is one of the widely used techniques that show outstanding results in NOx reduction in both light and heavy duty diesel engines. In the present study, the experiment has been conducted on a four-stroke, single-cylinder water cooled diesel engine. Here, a long-route EGR system was used in both hot (insulated) and partially cooled (without insulation) conditions. EGR rate was varied from 0 to 24% in steps of 6% and the engine ran at various load conditions. The research objective was to investigate the effects of varying EGR ratios and temperatures on engine performance parameters and determine the effective EGR rate where the engine gives high performance, low fuel consumption and produces low emissions.