液体火箭发动机缓冲式高压阀门关闭特性的流固耦合仿真研究

Fluid-Solid Coupling Simulation Study on Closing Characteristics of a Buffer High-Pressure Valve Applied in Liquid Rocket Engine

关键词:  液体火箭发动机  流固耦合  阀门  缓冲效果  关闭特性

Key words:  Liquid rocket engine  Fluid-solid coupling  Valve  Buffer performance  Closing characteristics

摘要:

针对大推力液体火箭发动机阀门密封副结构易受冲击、寿命较短的问题，本文设计了一款缓冲式高压阀门，并对其关闭特性开展了流固耦合仿真研究。本文的仿真工作采用了基于任意拉格朗日欧拉法（Arbitrary Lagrangian-Eulerian，ALE）的动网格技术，研究了阀门结构对缓冲效果的影响，获得了阀门关闭过程的动态流场特性与阀瓣运动特性。结果表明，相对无缓冲阀门，缓冲结构可使阀门动量增量绝对值减小25.14%，从而有效解决高压阀门关闭过程中产生的水击压力峰过大及对主阀座产生过强冲击问题，缓冲效果受最小环缝间隙与壳体间隙影响较大；最小环缝间隙与壳体间隙越小，缓冲效果越好；壳体间隙较小时，阀瓣主要表面压力更小，更有利于保护阀门部件与管路系统。

Abstract:

The sealing pair structure of valve applied in the high-thrust liquid rocket engine is vulnerable and has a short life. In order to solve these problems， a buffer high-pressure valve was designed in the paper. Closing characteristics of the valve were studied by a fluid-solid coupling simulation.The dynamic mesh based on Arbitrary Lagrangian-Eulerian （ALE） method， was adopted in the simulation to study the influence of the valve structure on the buffer performance. The dynamic characteristics of flow field and valve disc movement during the closing process were obtained.The results show that compared with the non-buffer valve， the buffer structure reduced the absolute value of valve momentum increment by 25.14%， so as to effectively solve the problems that pressure peak of water hammer is too excessive and impact on the main valve seat is too strong during the closing process. In addition， the buffer performance was greatly affected by the minimum annular gap and the shell gap. The smaller the minimum annular gap and the shell gap， the better the buffer performance. In particular， when the shell gap is small， the pressure on the main surface of the valve disc is relatively smaller， which is more beneficial for the valve components and the pipeline system.