Heat release analysis of hydraulic free piston diesel engine

A simplified method is used to calculate the Rate of Heat Release (RoHR), some notice details are considered. The data is smoothed to get the final curves, we analyze the parameters of original formula of Wiebe and they are fitted the well except several cycles. Not all the cycles are conformed to the complete premixed combustion characteristics. We get several cycles to distinguish the factors of premixed combustion and diffusion combustion in HFPDE, a parameter J is quoted to describe the possibility of diffusion combustion. And then we analyze the working process of HFPDE based on the characteristics of the curves. Fortunately, we find that the stability of ignition can be improved by changing the fuel injection time appropriately. Finally, we find the most suitable fuel injection quality of HFPDE, and the optimum proposals are presented. However, the specific method to reach the goal and internal cause of RoHR characteristics are not given.