An Analysis Of Influencial Factors Of The Water Hammer's Wave Velocity In Pressure Pipeline And A Study On Its Influences Upon The Calculation Of Water Hammer In The Long-distance Water Delivery Pipelines

Long-distance water delivery project are being seriously in order to solve the problem that water resources are not well-distributed in time and space in our country. In the long-distance water delivery project, the research work of water hammer is very important for the safe operation of long-distance water project, As an important influencing factor of water hammer, the wave velocity of water hammer is not to be neglected. The text has made a comprehensive theory analysis on the influencing factors of water hammer on the basis of research achievement of the predecessors and has also made a further study on the influence of wave velocity on the water hammer boosting pressure combining with project cases.This text began with the status quo of water resources distribution, and state progressively the background and significance of water hammer research work. The text has also introduced comprehensively the research status quo at home and abroad and some of the basic concepts in the water hammer research work. We deduced the formulary of wave velocity on water hammer and emphasized the influences of it. In addition, we introduced briefly the calculation method of water hammer and boundary conditions. Combining two projects cases, we emphasized the influences of wave velocity on the water hammer boosting pressure. Finally, we gave the conclusions and recommendations.One key of this text is influencing factors of water hammer. Wave velocity of water hammer is a complex physical quantities, it have a lot of influence factors. Some factors are easy to quantitative analysis, for example, the pipe diameter, the thickness of pipe, the temperature of fluid temperature, the pressure and so on. Some factors are not easy to quantitative analysis, such as restraint of pipe, the material of pipe, cross-section ratio of the pipe, the quantity of mixed atmosphere, the shield of pipe, etc. These all have influences on the wave velocity of water hammer water, and we theoretically analysed these factors one by one.The other key of this text is researching the influence of wave velocity on the water hammer boosting pressure combining with project cases. The calculation method of water hammer in this text is method of characteristics that is always used. We chose two project cases, one is Fugu pump station and the other is Yanchuan pump station. The former is high-lift, small diameter and flat, the latter is high-lift, big diameter and rolling. They are both typical. For each case, we took different protection scheme. The strength of these schemes is enhancing step by step, so the boosting pressure of water hammer is different. The ultimate aim of this text is offering theory support and reference for selecting protection scheme of water hammer. In this text, we analysed the influencing factors of water hammer and studied the influences of wave velocity on the water hammer boosting pressure. I hope this text will be helpful for the safe operation work of long-distance water delivery project.