The Reaserch On The Protection Of Water Hammer In Large-scale Regional, Pressure Flow And Long Distance Water Supply System

Because of China's population growth and rapid economic development, water consumption increased, and with the relative shortage of water resources and pollution are serious problems, Therefore, China has invested a lot of human and material resources to build long-distance water conveyance project. In the long-distance water conveyance project, the most common and most prominent problem is the water pipeline security issues. How to conduct effective protection of water hammer is the designer at home and abroad need to be addressed urgently, we need more in-depth research..In order to research how to alleviate water-hammer of the long distance water supply pipe more deeply, this thesis described the evolution of the hydraulic flow pattern in the long-distance water pipelines on the basis of the conclusion of the theory and experience of our predecessors. Use "The Reaserch on the Protection of Water Hammer in Large-scale regional, pressure flow and Long Distance water supply system" as the research direction.And discussioned step-up pressure problems and harm of air chamber movement in the pipeline and the best way of exhaust. Then give a deeper analysis about the structure and capability of the equipments which is common use used on water supply pipe, and discuss that what equipments is demanded in order to alleviate water-hammer in long distance water supply program. According to the character of water hammer in long distance flat water supply pipe, the hazard of air chamber motive was analyses.This thesis summarizes the calculation of water hammer in the basic principle and boundary conditions for solving computer formula of the tank, centrifugal pump, slow close check valve, exhaust valve, surge tank, pressure relief valves, etc, which in the water hammer calculation process. Water hammer protection measures of large region of the long-distance pipe flow pressure of the pumping station and pipeline system were analyzed, and the water hammer protection measures are summarized, and the structure and working principle of box-type two-way surge tank which is a new water hammer protective equipment was described. Based on the different of cavities water hammer cavity medium, water hammer Cavities were classified.Method of characteristics which is widely used in hydraulic transient's analysis is described in this thesis, establish the basic mathematical model of calculation of water hammer which combine method of characteristics and various types of boundary conditions. wrote the visual program of water hammer calculation with the computer language, made use of the computer to carry on Water Hammer calculation Analysis. There are the reference value of long-distance water pipelines hydraulic transient analysis.The end of this thesis, water project in Algeria and Liaoning Dahuofang Reservoir as an example to conduct a simulation of water hammer protection. According to the results of calculation of water hammer, water hammer of various protective measures were compared. Protective measures in different water hammer have the different effect in the course of water hammer protection is verified. Advance the best comprehensive protective measures of water hammer Cavities in the long-distance large-scale regional water pressure flow of water hammer protection system, to provide reference for the selection of water hammer protective equipment in the long-distance water conveyance project.