The Influence Of Parameters On The GDI Engine Combustion Process Research

In cylinder direct injection gasoline engine in high speed and large load uses the intakestroke injection and homogeneous propellant combustion，fuel and air mixing proportion is1.It can take Three Way Catalytic Converter to handle exhaust and meet the requirements ofemission regulations. It is one of a Important development direction on direct injectiongasoline engine. Mixture quality directly affect the combustion process. So in this paper， westudy the parameters of the mixture formation and combustion process. Such as the flow fieldin the cylinder， injection timing and ignition timing. It can provide methods and techniquesof theoretical reference to optimize the Direct injection homogeneous combustion andreducing emissions.In this paper， using the CAD modeling Pro-E， the model importAVL-FIRE software，and then to carry on the grid，set the initial and boundary conditions and calculation thenanalysis to discuss the results are as follows:In this paper，the research object exists obvious rolling flow in high speed heavy load incylinder from the intake stroke to the ignition time continuous. This is good for the formationof the mixture.In a given under the condition of injection pressure and injection quantity，when80°CA ATDC injection， The spark plug gap have slightly rich mixture.It is suitablefor the ignition，and the overall equivalent ratio in cylinder close to the chemical mixtureequivalent ratio1on ignition timing.It is suitable for homogeneous combustion; when100°CA ATDC.injection， injection later， fuel and air mixing time is short， there is a smallamount of fuel is not evaporated The quality of mixture formation is poor.It is more than60°CA ATDC and100°CA ATDC injection combustion performance..Keeping constantinjection pressure and injection mass and choosing80°CAATDC injection scheme，Ignition timing20°CA BTDC can ensure that the average temperature in cylinder， also can ensurethe maximum pressure and heat release rate.