水电站坝下尾水渠集鱼流场模拟研究

为减缓大坝阻隔对鱼类洄游的不利影响，水电工程需要建设有效的过鱼设施疏通其洄游通道。高寒区高坝大库工程过鱼设施建设是一个极其复杂的技术问题，目前国内类似工程尚无成功运用经验。实际过鱼设施内流场条件十分复杂，会产生不利于鱼类上溯的水流形态。基于此原因，对某水电站工程坝下尾水流场进行了数值模拟。研究表明，在机组运行时，电站尾水渠左右两侧发电尾水主流的边缘是明显具有流速梯度分布的区域，符合鱼类聚集的水流特征，具备布置鱼道进口条件。这样可根据尾水位的变化开启两侧不同进口诱鱼，且在机组停运时，可开启左侧进口诱鱼。

Simulative study on fish-collecting flow field of tailrace channel under dam for hydropower station

In order to alleviate the adverse impact from the blockage of dam on fish migration，effective fish-passing facility is necessary to be built up for hydropower project to unlock fish migration passage． It is a very complicated technical matter to construct the fish-passing facility for the project of high dam and huge reservoir in high-cold area，while no successful application experiences are there for the similar projects at present in China． The flow field condition inside the actual fish-passing facility is quite complicated，under which the flow pattern that is unfavorable for the upstream migration of fish is to be formed． For this reason，a numerical simulation is carried out on the flow field of the tailrace channel under the dam of a hydropower station． The study result shows that both the right and left sides of the tailrace channel for the hydropower plant are the edges of the main stream of the tail water from power generation and the obvious areas of velocity gradient distribution during the operation of the hydropower plant，which are consistent with the characteristics of the flow conditions for fish aggregation，thus have the conditions for arranging fish-way． In this way，different inlets on the both sides can be opened to lure fish in accordance with the change of the tailrace water level，while the inlets on the left side can be opened for fish luring when the power generating units are shut down．