针对气体燃料发动机燃气成分多变等特点，从双燃料分开式燃烧室这一情况出发，以各室工质的瞬时成分、温度来计算其比热、内能、焓等热力参数，建立了以实测燃烧室压力为输入参数的放热率分析模型，适用于纯液体燃料、气体燃料以及双燃料工况下直喷式、分开式燃烧室发动机放热率的分析计算。文中给出了计算及应用实例 Aiming at the characteristics of variable gas composition of gas fuel engine and so on, the thermal parameters such as specific heat, internal energy and enthalpy were calculated from the instantaneous composition and temperature of working fluid in each chamber based on the situation of dual fuel split combustion chamber. The measured pressure of the combustion chamber is the heat release rate analysis model of the input parameter, which is applicable to the analysis and calculation of the heat release rate of the direct injection and split combustion chamber engines under pure liquid fuel, gaseous fuel and dual fuel conditions. The article gives the calculation and application examples