The Water Dispatch Simulation And Control Of South To North Water Diversion Jiao-dong Route

Jiao-dong Route as a pioneering work of South-to-North Water Transfer East Line Project, which has solved the problem of the shortage of water resources in north China. Jiao-dong trunk as a complex long-distance water channel, has numerous of canal system building, and its water delivery scheduling is complex. Under normal water condition and the abnormal water conditions, a slight decision-making errors are likely to cause the bank instability, channel lining board, and other complex hydraulics problems(channel water level fluctuation, water levels fall too fast), During freezing period, which easy to cause the problem of ice jam, ice dam, and the efficiency is low. So it is necessary to have an in-depth study on the water supply and control of the Jiao-dong trunk project.On the basis of Jiao-dong water mains mathematic control model, by setting boundary conditions, and using numerical simulation method, studying on the several kinds of channel condition, The specific research contents and conclusions are as follows.(1) Using downstream constant level control method and midpoint of depth control method, of the wave process of the water level in the channel and the stable time under the two kinds of operation conditions are analyzed and comparised. These two conditions are channel flow increase and decrease. The advantages and disadvantages of two methods of control are concluded.(2) Using different ways of brake control to simulate the variation of the level and flow downstream, under the normal and abnonormal conditions. Result show that, with the brakes no control, the level of down-stream are falling faster than the maximum water levels fall speed, that may cause bank instability and lining plate collapse. In a sequential close the brakes or close the brakes at the same time, it can effectively reduce fall speed of the water level, and control quantity of flow in time. However, comparison the closing brakes orderly and closing the brakes at the same time, we can see that, the fall speed of water level of the method that closing the brakes at the same time, are less than that close brakes orderly.(3) Under coditions of different brakes closing time in accident prone location, water level waving progress and that of upper level in channel are studyed caused by sudden accident. Research showed that channel water level fluctuation is more larger with the brakes closing time being more shorter, and more shorter of flood time in upper stream. Therefore, if run of down-stream operation is safe, brakes closing time can be shorten appropriately.for fear that other accidents occur under influence of large water level fluctuation caused by gates closing too fast.(4) Analysis the characteristics of water transfer during freezing, calculated and compared the flow capacity during freezing and that during normal. Result show that the flow capacity is decreased about 17% than that of no glacial. Therefore, in order to improve the efficiency of ice water, the water level should be raised during freezing.