大型电站叠梁门分层取水进水口水力特性研究

电站进口前加设叠梁门后引起局部水流条件复杂,本文以模型试验和数值模拟为研究手段,系统阐述了叠梁门分层取水进口水流流态、门顶最小运行水深、水头损失和叠梁门反向附加水击压力等。研究表明,加设叠梁门后机组各栅孔进流较为均化,门井水面波动加大,主要引流区间在门顶以下10 m—门顶以上25 m水域,叠梁门门顶最小运行水深一般为15~30 m,进口段水头损失1.20~1.95 m(水头损失系数为0.45~1.15),较无叠梁门时增大1.11~1.63 m,对机组发电经济效益将产生一定影响,机组甩负荷对叠梁门下游面板产生的附加水击压力(2.9~3.0)×9.81 k Pa。

Hydraulic characteristics study on stoplog gates multi-level water intake of large hydropower station

Setting stop log gates in front of power plant inlets leads to complicated local flow conditions. The flow pattern at inlets,the minimum depth at gates,the water head loss,and the additional water ham-mer back pressure on the stop log gates are systematically studied based on physical model testing and nu-merical simulation. The results indicate that,the inlet flow at each gate hole of power units was more uni-form, and the fluctuation of water level in the valve pit increased if the stop log gate was set. The main water-intake area ranged from 10m under the gateway top to 25m above the gateway top, and the mini-mum depth at gates was 15~30m in general.The water head loss at inlet was 1.20~1.95m(head loss coeffi-cient equal to 0.45~1.15), which was 1.11~1.63m higher compared with that without stop log gates, and the economic benefits of power units were then affected. The additional water hammer pressure on the down-stream panels of stop log gates was(2.9~3.0)×9.81kPa,under load rejection operating conditions.