与宽尾墩联合使用的消力池体型优化研究

Experimental study on shapes of stilling basin combined with flaring gate piers

与宽尾墩联合使用的消力池体型不同,消力池临底流速就会出现不同的分布规律。通过对工程实际中已经存在的几种消力池体型的分析,借助鲁地拉工程试验模型,对与宽尾墩联合使用的消力池体型进行了探索研究。研究结果表明,坝脚处设置双圆弧嵌槽＋池末端复合式尾坎组成的嵌槽式消力池,在保持原传统戽式消力池体型整体水流流态不变的条件下,可以利用双圆弧嵌槽对消力池近底水流进行导向,导向后的水流既减小了消力池水流近底流速,又使近底水流的部分旋滚上移,充分利用了消力池中上部水体的紊动消能作用。实测消力池近底流速减小幅度平均在15%~30%之间。脉动压强的测试分析结果表明,最不利运行工况时,嵌槽对脉动压强均方根的减小有一定效果。

For a stilling basin in combined use with flaring gate piers, the flow velocity near its bottom much depends on its geometrical shape. This paper presents a study of hydraulic model tests to optimize the shape of the Ludila stilling basin, considering several commonly-used existing shapes. Our model tests show that if such a stilling basin is modified with an embedded notch in combination of double arcs and a compound tail sill, the double arcs are able to guide the flow near the bottom so as to reduce the bottom velocity, hence improving the energy dissipation rate. In the stilling basin with the optimized shape, its bottom velocity can be reduced by 15%- 30% on average, and bottom pressure fluctuations also reduced even in the most unfavorable flow conditions.