Study of the Parameters for Controlling HCCI Engine Ignition Time

The effects of fuel composition,compression ratio,air-fuel equivalence ratio,inlet air temperature and pressure on the homogeneous charge compression ignition(HCCI) engine were studied by taking the mixture of the DME,methane/propane,and mixture of n-heptane and iso-octane as the fuel.The calculation results indicate that the ignition delay is reduced with the increase of octane number while it is raised with the increase of octane number.The compression ratio,air-fuel equivalence ratio and inlet air temperature have great effects on the ignition time of above three kinds of fuel.The inlet air pressure has the relatively less influence on the ignition delay of the high octane number fuel,but has an obvious effect on the ignition delay of the high octane number fuel.