火电厂循环水系统高位集水池水面波动数值模拟研究

针对火电厂循环水系统高位集水池在水泵启动及事故停泵过程中的水面波动现象,利用CFD软件采用VOF方法,通过UDF给定瞬态边界条件,对某电厂流道承压式与流道开敞式两种设计方案的高位集水池,在3台泵同时启动及同时事故停泵过程中的水面波动现象进行了数值模拟。计算结果表明,启动工况及事故工况下,流道开敞式的钟形进水流道由于增加了钟形吸水室的自由水面面积,较流道承压式的肘形进水流道更能减弱对高位集水池段的水面扰动。在重点考虑高位集水池段在水泵启动及事故停泵过程中水面波动的情况下,建议采用流道开敞式的循环水泵房布置形式。

Numerical simulation study on water surface fluctuation of high cistern in circulating water system of thermal power plant

Aiming at the phenomenon of water fluctuation in the process of water pump start and accident pump stop in the high cistern of the circulating water system of thermal power plant. By using CFD software and VOF method, the transient boundary conditions were given by UDF. The water surface fluctuations of high cistern of pressure and open flow design a power plant were simulated during the simultaneous start of the three pumps and the simultaneous shutdown. The calculation results show that under the starting condition and accident condition, the bell shaped inlet channel with an open channel, which increases the free surface area of the bell shaped suction chamber, weakens the water disturbance at the high cistern than the channel pressure bearing elbow inlet channel. In the case of water fluctuation during the start of the pump and the shutdown of the accident, it is recommended to adopt the open circulation pump layout.