Abstract
Th effects of exhaust gas recirculation(EGR) on the characteristics of combustion exhaust emissions and specific fuel consumption(SFC) are experimentally investigated by four-cylin-der four-cycle and direct injection marine diesel engine. In order to reduce soot contents in the recirculated exhaust gas to intake system of the engines a novel diesel soot removal system with a cylinder-type scrubber which has water injector(4 nozzles in 1.0mm diameter)is specially designed and manufactured for the experi-mental system. The obtained results are as follows; The combustion pressure in cylinder is decreased and ignition is delayed with increasing EGR rate. The accumulated quantity of heat release is slightly decreased and the tendency of heat release rate is not constant. NOx and Soot emissions are decreased by maximum 7% and 540% with scrubber tan without scrubber in the range of experimental conditions. Those are increased at the lean burn area with increasing equivalence ration in the constant value of engine speed and EGR rate. Also those are decreased with increasing EGR rate in the constant value of engine speed and equivalence ratio.
