长距离供水工程是解决水资源时空分布不均的有效方式,工程运行中发生的水锤将严重威胁输水系统的安全。本文对长距离供水工程中关阀水锤特性进行研究,分析了长距离供水工程中的线路充填现象,推导了考虑摩阻的输水系统直接水锤公式,并对间接水锤公式进行了修正,同时探讨了其适用范围。结果表明:对于长距离供水工程,由于关阀过程中管道出现了线路充填,发生的直接水锤大小与关阀时间密切相关,关阀时间越短,直接水锤压力越大;当关阀时间大于一个相长时,长距离供水系统所产生的间接水锤压力数值上也可能超过直接水锤,修正后的间接水锤公式不仅可用于供水系统水锤分析,同时为折线关阀规律的设计提供了理论依据,计算结论为长距离供水工程的管道设计及运行调度提供了参考。
Long-distance water-supply project is an effective way to solve the uneven spatial and temporal distribution of water resource,the safety of water conveyance system is seriously threatened by water-hammer. Based on the long-distance water-supply project,the characteristic of water-hammer and line packing is analyzed,the formula of direct water-hammer deduced,indirect water-hammer also modified,and the application scope of formula discussed with friction considered. The results show that direct water-hammer is closely related to closure time of valve,the shorter the time,the greater the pressure; the closure time of valve is longer than phase length,the indirect water-hammer may exceed the direct water hammer because of the line packing happens in the long-distance water-supply project,the modified formula of indirect water-hammer can not only be used for analysis on water-hammer,but also provide a theoretical basis for the design of broken-line shut mode,the conclusion of calculation provides reference for pipeline design,operation and dispatching for long-distance water-supply project.