Abstract: A isobaric pre-combustion rotating detonation engine(RDE)cycle was proposed to solve the ignition conundrum of kerosene and air. Thermal efficiency model of the isobaric pre-combustion detonation cycle was built by zero dimensional method. The results show that the thermal efficiency of isobaric pre-combustion detonation cycle is higher than that of ideal Brayton cycle and lower than that of ideal detonation cycle. The air ratio of isobaric pre-combustion effects on thermal efficiency greatly. When the cycle temperature ratio is 2 and the pre-combustion air ratio is 0， the thermal efficiency of pre-combustion detonation cycle is 26.4% higher than that of the ideal Brayton cycle. The thermal efficiency rising percentage of pre-combustion detonation cycle declines with air ratio increasing. Pre-combustion is conducive to liquid kerosene detonation ignition. Also pre-combustion have obvious advantages in low temperature ratio and low pre-combustion air ratio condition. As little as possible air should be used under the successful ignition premise in the experiment.

Key words: Two stage combustion；Rotating detonation engine；Thermal efficiency；Pre-combustion；Performance analysis

摘要： 针对煤油-空气旋转爆震发动机(RDE)点火困难问题，提出一种采用等压预燃的爆震循环模式。通过零维的热效率理论分析方法，建立了一种针对于带预燃的爆震热循环效率模型。结果表明，预燃爆震循环的热效率高于理想Brayton循环，低于理想爆震循环。预燃空气比例是热效率的重要影响因素，循环温比为2，预燃空气比例为0时，预燃爆震循环比理想Brayton循环热效率高26.4%，而当预燃空气量逐渐增加，预燃循环效率提升的比例逐渐变小。采用预燃方式有利于液态煤油的点火起爆，在低温比，低预燃空气比例条件下优势明显。试验中应当在保证煤油能够起爆的前提下采用尽可能少的预燃空气。

关键词: 两级燃烧；旋转爆震发动机；热效率；预燃；性能分析