Simulation And Protection Research On Water Hammer Of Water Transmission Pipeline

Water-transmission line as an important part of the urban water supply system, its security, reliability have a close relationship with urban life and industrial production. With the continuous development of urbanization, urban water supply enterprises are increasingly developing, a lot of pump stations, water plants, water distribution network infrastructure. How to ensure the safe operation of infrastructure and production water safeguard people’s life become more important topic.The safety of the water pipeline from water source to urban water treatment plant in the urban water supply system is particularly important. In the event of failure, it will lead to paralysis of urban water supply system. In water-transmission line, the effect on the safety of the water pipeline is quite big because of stopping of pumps and misoperation of valve. Therefore, choosing the appropriate water hammer protection measures for prevention and control of water hammer in pipeline, ensure water pipeline safety operation, has the vital significance.Thesis on the basis of predecessors’ research study of water pipeline water hammer protection, mainly high lift many ups and downs water-transmission line of water hammer protection were studied. First introduces the genesis, classification and research status, and then introduces the basic theory and calculation method of water hammer and the commonly used water hammer protection measures. Aimed mainly at a two-phase closed controlled butterfly valve procedures as well as the secondary check what is commonly used in high lift many ups and downs water pipeline. From water hammer volatility into consideration for high lift many ups and downs pipe water conditions applied optimization research. And get the following main conclusions:① It can prevent water hammer produced by cut-out bridge that compound inlet exhaust valve set in the pipe height. In the fluctuation of water pipe, should be set according to the line profile elevation situation sui Tab. le inlet exhaust valve.② Composite pipe of equivalent wave velocity reduced if the single pipe of water hammer wave speed, can rise to weaken the effect of water hammer. Many ups and downs water-transmission line can choose composite pipe when the pressure.③ High lift many ups and downs in water-transmission line, the use of two stage closing butterfly valve and compound inlet exhaust valve used in combination, has a good effect of water hammer protection. Two-stage closing butterfly valve application according to the following method carries on the preliminary choice: quick close valve diachronic t1= C ∑Liai, slowly shut for t2 can according to the t2=(5~7)t1.④ The major influencing factor of effect to the two-level check is distance from pumping station. The pressure will increased in front of the two-level check. It should choose the appropriate check valve. It should be calculated according to the condition of pipeline and the setting position,if the slow close check valve was used.