某核电站疏水管线异常振动特性分析

Analysis of the Flow-induced Vibration Characteristics of Exhausting Pipelines in a Nuclear Power Plant

针对某核电站疏水管线发生的异常振动失效情况,开展管道热工水力特性及基于流固耦合数值方法的振动力学特性研究。计算结果及分析表明:瞬态工况下阀门迅速关闭形成的流体冲击导致管线的异常振动,引起的流体压力波动作用于关闭的阀瓣上,导致阀门本体与头部之间的连接支撑架局部应力过大,从而引起弯曲变形。计算阀门头部最大变形量与实际变形量接近,表明本文分析方法正确可靠,可为管线及阀门瞬态流致振动分析提供借鉴及参考。

A fluid-structure interaction method was applied to study the thermal-hydraulic and vibration dynamic characteristics in exhausting pipelines with abnormal vibrations. It was proved by the results of analysis that the abnormal pipe vibration was caused by the quick valve closing. This valve actuation in turn generated a fluid pressure fluctuation on the disc of the closed valve. As a result, the local stress on the support between the valve body and the head component was so large that the bending deformation of the support occurred. It is found that the calculated deformation of the valve head is closed to the real deformation. So, the analysis method is proved to be correct. This dissertation can be referred to for transient fluid-induced vibration analysis on pipelines and valves.