球型调节阀关阀水锤效应的试验研究与数值计算

针对工业生产中球型调节阀快速关闭时产生水锤的现象,采用试验方法和数值计算分析关阀速度对水锤冲击波形的影响.研究结果表明,随着阀门关闭,阀前压力先增加后降低,阀后压力先降低后增加,二者几乎同时达到峰值和谷值,并都伴有一定强度的随时间推移快速衰减的压力波动.关阀水锤效应对阀前管路的冲击更强,并且阀前正压力与阀后负压力会产生合力,对阀体结构造成更大的水锤冲击力.关阀时间从3 s增加到5 s,可降低水锤冲击力,同时会改变水锤冲击波形.基于经典水锤方程和特征线法,建立一套快速分析关阀瞬态性能和水锤冲击效应的数值计算方法.自主开发计算软件,数值结果与试验数据基本吻合,能够较好地预测关阀动态过程和管道水锤现象,为相关工程应用提供技术支撑.

Experimental study and numerical calculation of water hammer effect of closing valve of ball type regulating valve

With respect to the water hammer phenomenon caused by the rapid closing of the ball type regulating valve in the pressurized water reactor nuclear power plant, both experimental method and numerical calculation were used to study the water hammer effect of the closed valve, and the influence of the closing speed on the water hammer impact waveform was analyzed. The results indicate that with the closing of valve, the pre-valve pressure increases first and then decreases, and the post-valve pressure first decreases and then increases. The pre-valve pressure peak and the post-valve pressure valley are reached almost simultaneously, which are accompanied by pressure fluctuations that decay rapidly over time. The water hammer effect of the closing valve has a stronger impact on the pipeline before the valve. In addition, the positive pressure before the valve and the negative pressure after the valve will produce a resultant force, which causes a greater water hammer impact on the valve body structure. When the valve closing time increases from 3 s to 5 s, the water hammer impact force can be reduced and the water hammer impact waveform can be changed as well. Based on the classical water hammer equation and characteristic line method, the calculation software was independently developed, and a set of numerical calculation methods for quickly analyzing the transient performance of valve closing and water hammer impact effects was established. By comparing the experimental data, the reliability of the software was verified. The calculation software can predict the valve closing dynamic process and pipeline water hammer phenomenon, which can support related practical engineering applications.