某电厂循环水供水系统正常停泵过程的仿真研究

Simulation on the transition process of usual pump off for circulating water supply system in power plant

针对某电厂循环水供水系统的特点,应用AFT ImpulseTM 4.0动态流体(水锤、汽锤)分析软件,对系统正常关机停泵水力过渡过程进行了计算机仿真,对泵出口阀不同两阶段关阀规律对应的过渡过程进行了比较分析,得出了较理想的关阀规律。根据仿真结果,正常关机同时停泵工况下,不当的关阀规律会导致水锤压力较大;而正常关机停1台泵或几台泵工况下,管道压力变化较小,泵反转比例是暂态过程中的控制点,较大的泵倒转比例容易损坏泵体。经计算机仿真计算得出的结论对提高电厂循环水系统的可靠性和运行稳定性具有一定意义。

In accordance with the characteristics of circulating water supply system in a power plant,a dynamic fluent（water hammer or air hammer） analysis software of AFT impulseTM 4.0 was applied for computer simulation of usual pump off in transition process.Comparing the transition process corresponded to different two-stage valve closing regulations,the optimized operations for closing valve were obtained.According to the simulation results,a wrong closing valve regulation could result in rising of water hammer pressure when all the pumps off usually.Under the conditions of one or more pumps stopping,the variation of pressure was small,and the pump reverse scale was the control point in transient process,higher pump reverse scale could destroy the pump easily.The conclusion had certain significance to improve reliability and stability of circulating water supply system in power plant.