The Study On Numerical Simulation Of Flow Balance And Security In Yumenkou Projent Of Shanxi Province

The large-scale water transfer projects of our country have the features of big water-transfer, long line, complex engineering, huge investment and so on. The condition of water resources distribution is complex along the region, and there is a close relationship between flow and head. However, in the pumping station, there're huge installed power and large generating unit. When the scheduling decisions are improper in practice, it will cause the operations of opening or shutdown are too frequent, and it also will cause overtopping of the channel or excessive fluctuation in water level. Then this will lead to energy waste, equipment life reducing and even occur a safety problem.All above will affect the normal and efficient operation of the project. So it is necessary to adopt a scientific and reasonable schedule to achieve the security and stability of water transfer pumping station project and efficient economic operation.Meanwhile, the phenomenon of rising sharply or reduced of water flow velocity which is caused by the sudden changes of water flow speed in a high-head, long-distance water supply project is called pumping water hammer or hydraulic transition process. Water hammer could cause a great destroy on the water supplying project, the water hammer pressure of pumping stopping due to accident is 1.5-4 times of normal pressure. When water flow is cut off and then connected, the water hammer pressure is greater. There are many water supplying projects suffered from serious damage because of the water hammer which due to the accident, and this should cause great loss. So the calculation of hydraulic transition process in high-head, long-distance water supply project has becoming a important research topic of water supply project safety operation.The main content of this paper is:(1) Establish the balanced analysis numerical model of cascade pumping station.(2) build the models of analyzing pump station flow when changing speed and not changing speed, providing support for analyzing flow-balance between pump station.(3) build the models of analyzing water hammer on different kinds of pumps paralleling, Meanwhile, build the models of analyzing boundary of pump and air valve.(4) build the models of analyzing pump station flow when changing speed and not changing speed about yumenkou project, programming these models into VB module, format the results into forms, providing the support for optimizing the project.(5) numerical simulation the water hammer of pump station under kinds of safeguard procedures in huihe project of yumenkou project. Optimizing regular pattern of valve occluding, confirm the location for valve and the scale, raise the reasonable working system for the water supply project.(6) Chose Visual Basic 6.0 as the development language is, database is SQL Server 2000, using them developed a friendly interface, complete functions, easy operation, reliable stair pump stations's flow equilibrium system and pumping station water hammer numerical simulation system.