阀门特性对泵站水力过渡过程的影响

在泵站有压管道输水过程中，控制阀用于防止事故停泵时的水泵飞逸反转，但不可避免地引发关阀水锤，对输水管道不利。因此，何种阀门特性不但能够有效防止水泵飞逸反转，而且对于控制关阀水锤最为有利成为了研究重点。通过理论推导，建立了水泵出口控制阀门的相对流量系数与阀门相对开度的理想关系模型。继而，以实际工程为例，通过水力过渡过程数值模拟，对比分析了几种典型的阀门特性，评估了提出的理想阀门特性的水锤控制效果。结果表明，控制阀特性是泵站水力过渡过程的重要影响因素，理想的控制阀特性应为下凹形特性。当水泵出口控制阀门采用上凸特性时，阀门出口的最大水压很大，应避免选用；当水泵出口控制阀门具有下凹的理想特性时，同样的关阀条件下阀门出口的最大水压显著降低。此外，理想阀门特性对于提高管路沿线最小水压也是有利的，有效避免了负压的产生。提出的控制阀理想特性模型可为调水工程中水泵出口控制阀的选型提供重要的理论支撑。 The control valve is used to protect water pump from falling back when pump is stopped accidentally.But it is inventible to cause water hammer which is unfavorable to the water pipe line.Therefore,valve characteristic which can not only effectively prevent the pump from runaway but is also valid for controlling the valve closure water hammer should become the research priorities .Firstly,an ideal relationship model between the nondimensional flow coefficient of pump outlet valve and relative valve opening was theoretically derived.Then,through the hydraulic transient simulations of practical engineering,several typical valve characteristics were compared,and the proposed water hammer control effect of ideal valve characteristic was evaluated.The results showed that the control valve characteristic was an important factor affecting the hydraulic transient of pump station,and the ideal characteristic should be concave.The pump outlet valve with convex characteristic should not be selected because the maximum outlet pressure was large.When the pump outlet valve had ideal concave characteristic,the maximum pressure at the valve outlet decreased significantly under the same valve closing condition.In addition,the ideal valve was also beneficial for improving the minimum pressure along the pipeline and prevents the form of negative pressure.The ideal characteristic model of control valve can provide important theoretical support for the selection of pump outlet control valve in water diversion project. “十三五”国家重点研发计划（2016YFC0401808）；国家自然科学基金（51909115）；江西省自然科学基金（20192BAB216038）；中国水利水电科学研究院流域水循环模拟与调控国家重点实验室开放研究基金（IWHRSKLKF201904）