Abstract: In order to study the effects of the pintle injector structure on combustion performance of the thrust chamber of LOX/CH₄ engine， a non-adiabatic stable diffusion flamelet model considering real-fluid properties was adopted in the numerical simulation of the transcritical combustion and flow in the thrust chamber of LOX/CH₄ engine with pintle injector. The results reveal that two recirculation zones can be formed near the thrust chamber head of engine with pintle injector. When the width of the radial injection channel and the diameter of the needle decrease within a certain range， the chamber pressure and the gas temperature can be increased， and the combustion performance of the thrust chamber can be improved. In addition， for the value of the ‘skip distance’， in order to improve the combustion performance of the thrust chamber and consider the cooling of the thrust chamber head， the value of the non-dimensional ‘skip distance’ should be around 1.

Key words: Pintle injector;LOX/CH₄ engine;Thrust chamber;Combustion characteristics;Numerical simulation

摘要： 为研究针栓式喷注器结构对液氧/甲烷发动机推力室燃烧性能的影响，采用非绝热稳态扩散火焰面模型，并考虑真实流体的物性，对针栓式喷注器液氧/甲烷发动机推力室的跨临界燃烧和流动进行数值模拟。结果表明，针栓式喷注器发动机在推力室头部区域形成两个回流区；在一定范围内，减小针栓式喷注器径向喷注通道尺寸和针阀直径，可以提高燃烧室压力和燃气温度，从而提高推力室的燃烧性能；对于针阀伸进燃烧室长度，为提高推力室的燃烧性能，同时考虑推力室头部的冷却问题，应取越程比在1附近。

关键词: 针栓式喷注器;液氧/甲烷发动机;推力室;燃烧特性;数值仿真