EGR Oxidation and Catalytic Fuel Reforming for Diesel Engines

Abstract

Exhaust gas recirculation (EGR) treatment techniques that include combustible substance oxidation, catalytic fuel reforming, and partial bypass-flow control have been experimentally investigated on a single cylinder diesel engine. Application tests are conducted to investigate the effects of the reformed gases on the diesel combustion characteristics and exhaust emissions. This research is aimed at stabilizing and expanding the limits of heavy EGR during steady and transient operations by enhancing the premixed combustion that may significantly alleviate problems with soot formation and cyclic variations. Additionally, the heavy treated EGR is applied to enable in-cylinder low temperature combustion. A preliminary investigation on the effects of water addition to the high temperature catalyst bed is also conducted. The potential of EGR reforming is also examined for possible generation of synthetic EGR (CO2) at low engine loads. The effectiveness of the treated EGR on engine emission and operating characteristics are therefore reported.