长距离输水系统水锤影响因素及防护措施探究  

Exploration on influencing factors of water hammer and protective measures in long distance water supply system

作　　者：李江云[1] 周飞 LI Jiangyun;ZHOU Fei(School of Civil Engineering,Wuhan University,Wuhan 430072,China)

机构地区：[1]武汉大学土木建筑工程学院,武汉430072

出　　处：《给水排水》2023年第8期106-112,共7页Water & Wastewater Engineering

摘　　要：长距离输水系统因其空间跨度大,地形复杂等原因,遇到事故停泵或阀门切换时,水锤发生特点有其特殊规律。为此,梳理了长输系统规模、长度及地形条件等因素对水锤传播特性的影响及相应防护要点;比较了空气阀、空气罐及调压塔与泵后两阶段关闭蝶阀的联合防护效果。首先,大规模系统可通过设计较大的管径控制流速,达到水锤防护的目的;其次,当系统总扬程中静扬程占比较大时,停泵关阀后,较短系统的泵后压力峰值更大,较长系统驼峰处的水柱分离更严重。然后,起伏较大的地形将引发管线中更大的超压和负压,尤其在驼峰等位置易发生较大的水柱分离(或拉断)和水柱弥合(或撞击),从而导致泵后蝶阀难以抑制过大的压力波动,此时,需根据系统流量和地形特点选用空气阀、空气罐或调压塔进行联合防护。Due to large span and complex landforms,characteristics of water hammer in long distance water supply system have special regularities when encounters accidentally pump trip or valve switching.The effects of the key factors such as scale,length and topographic conditions of long distance water supply system on the surge characteristics of water hammer and the corresponding protections were summarized.The rulers of how to select protection measures of air valve,air vessel or surge tower with the two-stage closing butterfly valve behind pump were promoted.It is shown that the large-scale system can control flowrate by choosing proper pipe diameters to achieve water hammer protection.Secondly,when static head is relatively higher,the peak surge behind pump is more dramatic in the shorter system than in the longer one.The separation of water column at hump of longer system is more severe.Thirdly,undulating landform will trigger greater overpressure and negative pressure in pipeline,especially in humps,large water column separation(or collapse) and rejoining(or impacting) are prone to occur,it may cause butterfly valve behind pump to be unable to completely suppress pressure fluctuation.At this time,it is necessary to choose air valve,air vessel or surge tower for joint protection according to different system flow and landforms.

关 键 词：长距离输水系统 停泵水锤 驼峰 水柱分离与弥合 水锤防护 

分 类 号：TU990[建筑科学—市政工程]