COMBUSTION AND EMISSION CHARACTERISTICS OF PARTIAL HOMOGENEOUS CHARGE COMPRESSION IGNITION ENGINE

摘要

To investigate the effect of premixed fuel on the combustion and exhaust emission characteristics in a partial homogeneous charge compression ignition (HCCI) engine, an experimental study was performed. The premixed fuels are supplied by the additional fuel injection system in the intake manifold of a direct-injection diesel engine and the injection nozzle for directly injected fuel is equipped in the center of the combustion chamber. The results show that, in the case of gasoline as a premixed fuel, single-stage ignition is found, but premixing the diesel fuel is accompanied by a cool flame prior to the combustion of the directly injected diesel fuel. NO_x emissions in the partial HCCI engine with premixed gasoline fuel decrease linearly with increase in premixed ratio. But, for diesel premixed fuel, NO_x emission increases at high intake temperature and high premixed ratio conditions.