【摘要】 液氢/液氧富燃补燃循环发动机预燃室（即燃气发生器）产生的高温富氢燃气会与低温液氧一起进入主燃烧室进行燃烧，由于高温富氢燃气的高反应活性以及主燃烧室高压力环境，主燃烧室极易出现自点火现象，自点火与火焰的相互作用可能会导致出现类似“敲缸”的现象，因此亟需研究自点火发生的参数边界。针对此问题，本研究开发了跨/超临界非稳态小火焰面模型，开展了非稳态跨/超临界小火焰面计算研究，探究了高温富氢燃气/液氧的自点火特性。结果表明，燃气发生器全局当量比和标量耗散率会显著影响主燃烧室中混合物的自点火延迟时间。通过对多种工况的大量计算，确定了主燃烧室的自点火延迟时间范围为0.143 4～5.892 5 ms，并在燃气发生器全局当量比与标量耗散率空间确定了自点火发生的边界。更多还原

【Abstract】 For oxygen-rich staged combustion cycle, the high-temperature hydrogen-rich products from the gas generator is injected into the main combustion chamber together with cryogenic liquid oxygen. Due to the high reactivity of the high-temperature products and the high-pressure environment of the main combustion chamber, auto-ignition is highly likely to occur in the main combustion chamber. The interaction between autoignition and flame can lead to a phenomenon similar to the ‘knocking’, and it is urgent to study the parameter boundaries of auto-ignition. In response to this, this study developed a trans/supercritical unsteady flamelet model, conducted trans/supercritical unsteady flamelet calculations, and explored the auto-ignition characteristics of high-temperature hydrogen-rich products and liquid oxygen. The results indicate that the global equivalence ratio and scalar dissipation rate of the gas generator significantly affect the auto-ignition delay time of the mixture in the main combustion chamber. Through extensive calculations of operating conditions, the auto-ignition delay in the main combustion chamber was determined to be in the range of 0.143 4 ms to 5.892 5 ms, and the boundary of auto-ignition occurrence was determined in the space of the gas generator global equivalence ratio and the scalar dissipation rate.更多还原