瀑布沟水电站截流水流数学模型研究

在江河截流过程中,随着戗堤的移动,龙口处河床及河岸边界条件不断变化,给截流设计中的水力计算带来了很大困难。以瀑布沟水电站为研究对象,通过经过验证的数学模型计算,获得了截流期间设计流量Q=1 000m3/s,龙口宽度发生变化时,坝区附近研究水域内流态的变化情况,得到了不同口门宽下龙口附近的水力参数,包括断面平均流速、断面平均水位、垂线平均流速等。计算结果与物理模型试验结果的比较表明:二维水流数学模型计算龙口处的平均流速、戗堤上下游水位落差、龙中最大流速等结果与试验值较接近,可为水电站的安全截流施工提供技术支持。

Research of river closure flow mathematical model for Pubugou Hydropower Station

During river closure,the flow boundary of closure gap changes with the fold of closure dike,which brings a great difficulty to hydraulic calculation of construction design.In this paper the research area is a 750m long river section from the diversion tunnel entrance to the Pubugou Hydropower Station dam axis and the research tool is a two-dimensional flow mathematic model.When the closure design discharge is 1 000m3/s,different hydraulic parameters with various closure gap widths are obtained.These parameters include average cross-sectional flow velocity,average cross-sectional water level,average vertical flow velocity,and the planar distribution of water level and depth,etc.The consequences of the physical model test results show that the average flow velocity in the closure gap,the water fall upstream and downstream the closure gap,the water level and depth near the closure gap are close with the experimental results.