Numerical Simulation And Protection On Water Hammer Of Transmission Pipeline Of High-lift Pumping Station

China is one of the world’s most water-scare countries,and the spatial and temporal distribution of water resources is uneven.At the same time,the demand of water resources is increasing,and the problem of water pollution is becoming more and more serious,which makes the contradiction between water supply and demand.In order to solve the contradiction between water supply and demand,under the guidance of the government in China in recent years,a large number of water delivery projects have been built,and a lot of security problems have been exposed during the water supply process,of which water hammer problem is particularly prominent.Based on this,how to avoid or reduce the water hammer to ensure the safety of pipeline during the water transport is with great significance.Therefore,this paper has studied the problem of water hammer protection for high-lift pump station.The researches made by this thesis include several aspects below.Firstly,the paper presents the basic theory and calculation method of water hammer,deduces the water hammer wave velocity calculation formula and water hammer basic differential equation,gives the characteristic line method to solve the water hammer method and water hammer to calculate the basic boundary conditions.Secondly,the basic principle of Hammer Software of water hammer analysis is introduced,and the common measures of water hammer protection in high-lift pump station are analyzed,and the technical route of water hammer protection based on Hammer Software is given.Thirdly,taking a high-head and large-flow water supply project as research object,this paper analyzes the effect of single water hammer protection on the four kinds of equipment of hydraulic control butterfly valve,air valve,single phase pressure regulating tower and overpressure relief valve,and obtains protection scheme of accident pump-stop,and taking a large-scale long-distance water diversion project from a petrochemical plant as the research object,this paper studies the comprehensive protection effect of water hammer in the above four kinds of equipment,and obtains the required protection measures for water hammer.This paper mainly draws the following conclusions:1.High-lift water supply project to stop pumping water hammer protection using a single protective measures is difficult to obtain better results,the use of a variety of protective equipment comprehensive can ensure water delivery safety.2.High-lift large-capacity double-pipe water supply project,air valve combines with pump side hydraulic butterfly valve joint protection program is recommended in double-pipe water supply project,single pipe water under overhaul situation,it is recommended to use single-phase pressure regulating tower combines with pump-side hydraulic butterfly valve protection program to avoid damage from accident pump-stop.if considering the cost of the project,it is recommended to reduce flow when it comes to the single-pipe water supply situation,which could use the air valve combines with pump side hydraulic butterfly valve joint protection program to prevent pump station from water hammer damage.3.The best program to prevent the high-lift long-distance water supply project from accident pump-stop water hammer damage,it is recommended to use of single-phase pressure regulator with air valve and pump-side hydraulic butterfly valve.As to the lowest cost program,air valve combines with pump end control butterfly valve schedule is recommended to ensure the pump station safety.