An Effect of Cooled-EGR on Diesel Engine Performance Fueled with Coconut-oil Methyl Ester
The purpose of this study is to explore an effect of cooled-EGR on the diesel engine performance fueled with coconut-oil methyl ester (CME). The exhaust gas was cooled by the water at room temperature and was fed to the intake manifold, and the EGR rate was changed from 0 % to 30 % at every 10 %. The engine performances were measured at several EGR rates, fuel injection pressures and timings. Test fuels were CME and commercial diesel fuel. In the case of high EGR rate at which the compression ignition was deteriorated, the ignition timing of CME was always earlier than that of diesel fuel, therefore CME had good ignitability as compared with diesel fuel under EGR application. When the fuel injection pressure was increased at high EGR rate, the ignition delay was improved by the fuel atomization and air-fuel mixing effect.