电厂泵房前池壅水高度计算研究

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

针对某电厂循环水供水系统的特点,对系统事故停泵导致泵房前池壅水的水力过渡过程进行了计算机仿真,对泵出口阀不同关阀规律对应的壅水过渡过程进行了比较分析,得出了较理想的关阀规律及相应的壅水高度。仿真结果表明,最大壅水高度发生在不关阀工况,且关阀规律选择不当、泵发生或不发生倒转对泵房前池壅水高度影响较大。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参考意义。

In accordance with the characteristics of circular water supply system in the 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 closing valve 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 important practice significance to improve reliability and stability of circular water supply system in power plant.