Abstract
Keywords
Combined Plasma EGR System, Non-thermal Plasma Reactor, Diesel Engine, NOx and Soot Emissions, Intake and Exhaust Oxygen Concentrations
Abstract
The effects of non-thermal plasma reactor and recirculated exhaust gas on performance and exhaust emissions under four kinds of engine loads were experimentally investigated by using a four-cycle, four-cylinder, swirl chamber type, water-cooled diesel engine with a combined plasma EGR system operating at three engine speeds. The purpose of this study is to develop the combined exhaust gas recirculation (EGR) control system with a non-thermal plasma reactor for reducing Nox and soot emissions simultaneously in diesel engines. The EGR system is used to reduce soot emissions. The plasma system in this study is a flat-to-flat type reactor operated by a plasma power supply. The experiments are performed at the fixed fuel injection timing of ATDC 4° regardless of experimental conditions. It is found that the brake specific fuel consumption rate slightly increases with the rise of EGR rate, but the range of fluctuation is very small, and the ignition delay increases with the rise of EGR rate. The results also indicate that NOx and soot emissions decrease and particularly soot emissions are reduced markedly at the middle loads as the applied electrical voltage of plasma reactor is elevated.