Study On The Way To Waterhammer Protection In Long Distance And Heavy Calibre Of Flow Flat Water Supply Pipe

With the development of the economy, long distance and large-scale water delivery cascade pumping stations are begin to be built. In the long distance water supply pipe construction project, the most outstanding problem is how to protect the pipe. Therefore, in order to guarantee security of the running of the water supply system, It is necessary to make water hammer analysis. According to actual characteristic of water hammer occur,the safe, reliable, effectively and economic measure of preventing water hammer is designed.Long carry water pipes, once accer water hammer,the damage is severity. Especially in water hammer of cavities collapsing, which pressure increase in value will be of ordinary water hammer of dozens of times. However, water hammer is hard to foretell by sense. At present, the most advanced method is the computer programming models, the location and size of water hammer in open aqueduct system. To be specific, is judged by the pressure line and set up the water hammer protective installations by particular case. Among the lots of hydraulic models, the major difference is whether reflecting the water hammer of cavities collapsing phenomenon and calculate The practice shows that water hammer of cavities collapsing is the objective exists and not be neglect. This paper with high lift,large diameter pipes,fluctuation and long-distance carry water pipes to study.According to both the interim computation models, to compare the result of two hydraulic calculate methods. At last, come to a conclusion that the hydraulics transition model of cavities collapsing conform the actual situation.In the paper, method of characteristics which is widely used in numerical calculation of water hammer is shown. The capacity of equipment to alleviate waterhammer is considered in using "Method of characteristics", boundary conditions of water pump under different work conditions and common water hammer protective measures are given. It's important to distinguish the capacity difference of the equipment for the project designer. For example, there is different gas vent valve, and there are different boundary conditions. According to characteristic method, built up the water hammer calculation mathematics model combined with all kinds of boundary conditions, wrote the visual program of water hammer calculation with the computer language, made use of the computer to carry on simulation calculation.Finally, take Wanggedu reservoir water supply engineering as the example, simulation calculation of water hammer protection. Based on the result of calculation, various protective measures of water hammer of cavities collapsing is compared with. Different water hammer protective measures have different effects is verified. It was a greatly help to made alleviate water hammer scheme in this power plant, and it can be chosen to similar project.