考虑摩阻的停泵水锤传播公式

在长距离供水泵站出现事故停泵时,泵后压力将迅速下降,管道沿线随着水锤波的传播将出现较大降压,水锤传播过程中管道沿线压力分布是泵站及管道设置水锤防护方案的重要依据。本文采用特征线法与理论分析相结合的方法,分析了泵站抽水断电情况下的管道沿线水锤压力传播过程,推导了水锤降压波沿管线分布及衰减公式。理论公式与数值计算表明:在考虑管道摩阻情况下,水锤降压波在传播过程中沿管道逐渐减小,二者吻合良好,可为管道沿线设置水锤防护方案提供参考。

Pump failure water hammer propagation formula considering friction in long-distance water supply system

Transient pressure distribution along a pipeline is important to water hammer protection for a long-distance water supply system. Once pump failure occurs the pressure behind the pump drops quickly after pump failure, and a long pipeline will be involved. Using the method of characteristics (MOC) and theoretical analysis, this paper analyzes the propagation of water hammer along the pipeline, and derives a formula for transient pressure decrease along the pipeline. The results show a good agreement of this formula with MOC calculation, and indicate that the pressure drop is diminishing along the pipeline if its wall friction is considered. The formula that takes an explicit form, is more convenient in the design of water hammer protection schemes.