Unsteady numerical analyses with high resolution for premixed charge compression ignition (PCCI) combustion were carried to make clear the effects of spatial fuel concentration distribution on ignition and combustion characteristics. Detailed chemical kinetics with elementary reactions and multi-component diffusion for n-heptane fuel system were considered to realize accurately the auto-ignition and combustion process. HCCI combustion analysis with CHEMKIN-Pro were also carried out by changing widely the condition of the premixed charge and the data for auto-ignition condition were accumulated. By comparing these results, we discuss the applicability of the multi-zone modeling for PCCI combustion.
