Research On Controlling Mode Of Sluice Gate In The South-North Water Transfer To The Middle Route Project

South-to-North Water Transfer Project is a complex long-distance water conveyance system. In some sections the length of pipeline are relatively long, they can't be ignored to be a node in numerical simulation. So both the pipe section and the open channel section must be divided into grid for numerical simulation. The water level should be fluctuate if the upstream gate and the downstream gate all closed in short time. It will be overflowed in the case of higher water lever, otherwise the stability of channel slope is threatened especially in the case of higher water level outside the channel slope. So it's very important that calculate the maximum water lever and channel base seepage to analyze the methods of gate control. It may provide guidance for practical engineering.The main contents include the following:Firstly, established a model for unsteady flow in Canal-pipes conjunctive which the pipe is relatively long, deduced the feasible formula for the canal-pipe section, introduced the processing method of inner boundary in numerical simulation and calculated it use of characteristics. Verified its rationality by contrast with the result of both numerical simulation and theoretical analysis.Secondly, reduced the channel base to two-dimensional seepage model, meshed for solving domain by technology of Delaunay barycentric stationing, and calculate it with the finite element method. Analysed that the water head difference's variation trend of inside and outside the channel lining. It provided the necessary reference for stability of channel slope.Thirdly, calculated a series of maximum water level, occurrence time and the. corresponding head difference between inside and outside of canal lining in the case of different gate closing time from Sha river to Ying river. Analysed the alternative way of gate controlling. Further calculated for the sections from Sha river to Ying river by this way, compared the results to the original. The gate control method is proved fesible. Guidance and advice were provided to actual project.