Research Of The Hydraulic Transient Process In Long Distance Pressure Water Pipe

With the rapid development of the human society,people's demand of the water is on the increase,which makes us feel nervous.But there are unbalance between the natural distribution of freshwater resources and geographic distribution of human existence and time distribution of the water yield is far from the demand of human life.Along with the increase of water pollution in recent years and freshwater area shrinking significantly,the water shortage problem is more serious.In order to solve the problem of the relative shortage of water resources and uneven distribution of time and space,China constructed many long distance projects of transferring water by investing lots of human resources?material resources and financial resources,which realized the water resources allocation from the rich areas to the shortage areas.In order to ensure the water quality is not affected by the outside environment,the most common in these projects is pressure water pipeline engineering,and the safety of pressure water pipeline is the most prominent problems.It is easy to cause the hydraulic transition process due to its longer routes and complex flow condition.One of the most common is water hammer and it will make the pipe produce vibration,even burst and cause a huge damage once appearing the phenomenon of water hammer.Therefore,in order to meet the needs of water and guarantee the safe operation of the water piping,the hydraulic transient for the long distance pressure pipeline should often be research.In this paper,on the basis of summary of long distance water transfer project development process,the article discusses the theoretical research results and calculation method on the hydraulic transition process,which analysis the method of the characteristic line and some solving equations of the boundary conditions on the hydraulic transition process.It establishes the basic model of long-distance water-transmission line water hammer's calculation by using water hammer numerical analysis software and combined with the characteristic line method and all kinds of boundary conditions' equations.Finally determining the optimal rules of valve's closing and opening,which combined with the instance of pressure water pipeline engineering of the south-to-north water transfer project water-transmission line's 17 entrance and the optimized analysis of the water pipe system's rules of valve's opening and closing by using the characteristic line method and technology of computer numerical simulation.The results also provide the reference and suggestion for engineering's design and operation.