液体火箭发动机混合比影响因素研究

Study on Influencing Factors of Liquid Rocket Engine Mixture Ratio

混合比是液体火箭发动机的重要性能参数。某型发动机在飞行、试车过程中出现了混合比偏低问题,根据发动机系统特点,建立了发动机系统的静态特性模型,采用非线性分析方法对发动机混合比影响因素进行了研究。结果表明:泵扬程偏差和泵后主系统流阻偏差是发动机混合比偏差的重要影响因素,泵效率偏差和涡轮效率偏差对发动机混合比偏差影响很小;在影响因素偏差较小的情况下,性能变化量与影响因素近似呈线性关系;造成混合比偏差的各种影响因素对发动机推力等参数影响不同,确定混合比偏差影响因素应与推力等参数协同分析。

Mixture ratio is an important performance parameter of the liquid rocket engine.A certain type of liquid rocket engine appears a low mixture ratio problem in flight and hot-test.The influencing factors of mixture ratio are studied by the non-linear analysis method with building a static characteristic model based on the engine system.The study results show that the deviations of pump head and main system flow resistance after pump are important influencing factors of the mixture ration deviation while the deviations of pump efficiency and turbine efficiency have little effect on the mixture ratio deviation.There is an approximate linear relationship between the performance change and influencing factor when the factor is comparatively small.Every influencing factor of mixture ratio has different influences on engine performance parameters such as thrust and cooperative analysis for the influencing factor of mixture ratio deviation and the engine performance parameters such as thrust should be carried out to determine the influencing factor.