多级降压调节阀流激振动特性分析

分析某管路系统多级降压调节阀的流激振动问题,仿真得到调节阀小开度、中等开度、全开3种工况下压力、速度、漩涡速度云图、压力脉动时域与频域特性曲线及流激振动频率范围。利用热流固耦合模态分析得到调节阀固有频率。将流激振动主频与固有频率相对比,验证调节阀工作可靠性。分析得出:随着开度增大,各级降压效果明显,大涡逐渐形成小涡,且形成脱落状态;压力脉动主要由开度引起,出口压力脉动剧烈程度大于中部及入口,调节阀出口下端的近壁面压力脉动最为剧烈;调节阀模态频率没有落在流激振动频率范围内,调节阀不会发生流激共振。为设计安全可靠的管路系统提供保障。

Analysis of Flow Induced Vibration Characteristics of Multi-stage Pressure Regulating Valve

The flow induced vibration of the multi-stage pressure regulating valve in pipeline system is analyzed.The pressure,velocity and vortex velocity nephogram of the valve under small opening,medium opening and full opening are obtained by simulation.The time-domain and frequency-domain characteristic curves of pressure pulsation are obtained,and the frequency range of flow induced vibration is obtained.The natural frequency of the valve is obtained by thermal fluid structure coupling modal analysis.The main frequency of flow induced vibration is compared with the natural frequency to verify the working reliability of the valve.The analysis shows that with the increase of opening,the depressurization effect of each stage is obvious,the large vortices form small vortex and fall off.The pressure pulsation is caused by the opening.The intensity of the pressure pulsation at outlet is greater than middle,greater than inlet.The near wall pressure pulsation at the lower end of the outlet of the valve is the most intense.The modal frequency of the valve does not fall within the flow induced vibration frequency range,and the valve will not have flow induced resonance,which provides guarantee for the design of safe and reliable pipeline system.