Abstract: The ideal thermodynamic cycle of 2-stage PDE based on Brayton cycle and ideal detonation cycle was established and analyzed in order to evaluate its performance. The rich combustion products and their fractions changing with equivalence ratio were calculated using CEA. The results indicate that the ideal thermodynamic efficiency and specific thrust of the ideal 2-stage PDE cycle, which are between Brayton cycle and ideal PDE cycle, decrease with increasing first-stage heat release ratio. According to the calculation results, the range of equivalence ratio of rich combustion should be 2.6~2.8 when for maximum concentration of hydrogen and Carbon monoxide. If taking the incompleteness and dissociation of reaction into account, the heat release would reduce and then the thermodynamic efficiency would increase. 

Key words: 2-stage pulse detonation engine; Thermodynamic efficiency; Rich combustion

摘要： 为研究两级脉冲爆震发动机的性能,以Brayton循环和理想爆震循环为基础,建立和分析了两级脉冲爆震发动机的理想热力循环,利用CEA软件计算了富油燃烧产物及其组分随当量比的变化。计算分析表明,两级脉冲爆震发动机理想循环的热效率和单位推力介于Brayton循环和理想爆震循环之间,且随第一级放热比增大而减小；为得到最多的氢气和一氧化碳,第一级富油燃烧当量比应在2.6~2.8；由于燃烧反应不能完全进行和离解反应的存在,使得第一级富油燃烧的放热量减少,循环热效率增加。 

关键词: 两级脉冲爆震发动机;热力循环效率;富油燃烧 