The effect of exhaust gas recirculation on performance and emission characteristics of HCCI engine

Abstract

In this work, performance and emission characteristics tests are conducted on homogeneous charge compression ignition (HCCI)-mode engine using mango seed methyl ester. And also the effect of exhaust gas recirculation (EGR) on performance and emission of HCCI engine is analysed. The three different percentages of EGR were added with intake fresh air at 15%, 30% and 45%. The objective of this work is to obtain the optimum EGR percentage based on engine performance and emissions. The brake thermal efficiency (BTE) slightly increased than conventional unmodified direct injection (DI) diesel engine. 15% of EGR shows higher BTE than other percentages of EGR added with HCCI engine. Specific fuel consumption of HCCI-mode engine is lower than the normal diesel engine. The exhaustion of harmful emission of oxides of nitrogen has been reduced when biodiesel is used in HCCI-mode engine. However, smoke and CO emissions were reduced in HCCI-mode engine compared with DI diesel engine and further decreased by using EGR in HCCI-mode engine. HC emissions are slightly increased for HCCI-mode engine.