Research progress on system oscillation and stability of liquid rocket engine
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摘要:
针对液体火箭发动机中与阀门相关和与燃烧组件相关的两类重要振荡，阐述了发动机系统振荡现象、振荡模式以及稳定性的研究进展。结果表明，与阀门相关的振荡主要表现为阀门自身和与管路系统耦合的两种不稳定振荡模式；重点是振荡敏感参数分析，难点在于自激振荡临界稳定参数的获取和振荡频率的辨识。与燃烧组件相关的振荡表现为与供应系统耦合的燃烧不稳定、与喷注过程耦合的燃烧不稳定以及燃烧过程自身不稳定三种模式；流量型稳定性机理研究较成熟，内在稳定性机理准确建模相对匮乏；对时滞模型的进一步探究和对燃烧过程数学模型的深入完善是今后系统级燃烧不稳定振荡研究的重难点。
Abstract:In view of two kinds of important oscillations related to the valve and the combustion component in liquid rocket engine, the research progress of the oscillation phenomenon, oscillation mode and stability of the engine system was expounded. The results showed that the oscillations related to the valve were mainly manifested as the instability of the valve itself and the coupling instability of the pipeline system. With focus put on sensitive parameter analysis, there existed difficulty in obtaining critical stability parameters and identifying oscillation frequency of self-excited oscillation. The oscillations related to the combustion component included three modes: combustion instability coupled with the feed system, combustion instability coupled with the injection, and instability in the combustion process itself. The research on the flow-type stability mechanism was relatively mature, but there was a relative lack of accurate modeling of the intrinsic stability mechanism. The further exploration of the time-delay model and the improvement of the combustion process will be the focus and difficulty of future system instability oscillation research.
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图 5 供应系统耦合燃烧振荡结构框图
Figure 5. Block diagram of feed system coupled combustion oscillation
图 6 喷注耦合燃烧振荡结构框图
Figure 6. Block diagram of injection system coupled combustion oscillation
图 9 真实阀门-发动机系统耦合振荡结构框图
Figure 9. Block diagram of real valve-engine system coupled oscillation
图 10 真实燃烧组件-发动机系统耦合振荡结构框图
Figure 10. Block diagram of real combustion component-engine system coupled oscillation
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