流量调节器管路系统自激振荡特性研究（液体火箭推进专刊）

流量调节器管路系统在小流量大压降工况下会出现低频自激振荡现象,为了深入认识自激振荡产生机理,结合某型自稳流型流量调节器及管路系统,基于流量调节器弹簧振子动力学模型开展数值仿真研究。数值仿真得出自激振荡频率为94 Hz,与发动机试验结果一致。自激振荡产生机理是流量调节器的液动力受滑阀窗口型面变化率影响对系统形成正反馈作用,流量调节器综合刚度小于零时系统失稳。分析了流量调节器结构参数对系统稳定性的影响作用,三角形滑阀节流口流通面积能够抑制管路系统自激振荡。结合某型流量调节器负载特性试验系统进行验证,得出随着流量调节器压降升高,管路系统稳定性变差,获得的幅频特性,稳定边界与试验结果一致。

Study on Auto Oscillation of Flow Regulator Pipe system

the low frequency auto oscillation will occur in the flow regulator pipe system in liquid rocket engine under the condition of small flow and large pressure drop. In order to understand the mechanism of auto oscillation, the dynamic model of the flow regulator was improved based on the centralized parameter method. Firstly, the results of numerical simulation show that the frequency of auto oscillation is 94 Hz, which is consistent with the engine test results. The results show that the hydrodynamic force of the flow regulator forms a positive feedback effect on the system under the influence of sliding valve window surface change rate, which makes the integrated stiffness of flow regulator less than zero. Secondly,the effect of the characteristic parameters of the flow regulator on the stability of the system is analyzed. The influence of different throttle orifice configurations of slide valves on the stability of flow regulator pipe system is studied. It is concluded that the flow regulator with the triangular slide valve orifice configuration can suppress the auto oscillation. Finally, based on the load characteristic test, it is concluded that the stability of the pipeline system becomes worse as the pressure drop of the regulator increases. The simulation results of the dynamic characteristics and the stable boundary are consistent with the experimental results.