X型与Y型宽尾墩流道内水流特性研究

宽尾墩改变了流道内水力参数分布,采用RNG k-ε双方程紊流模型,定量分析了沿程水位与流速的变化。结果表明,X型宽尾墩边墙水面壅高程度在闸室段前75%范围内,约从0增大至0.2,后25%区域内增幅较大。Y型壅高程度略高于X型,两者的差别在闸室段后25%范围内呈现增加趋势。宽尾墩使得闸室段中部速度梯度减小,且Y型墩对速度梯度的影响较X型更为强烈。受逐渐扩宽的墩体尾部影响,闸室出口速度方向和大小发生改变,速度沿水深的分布极为不均,特别是水流抛射方向的显著变化与水平方向速度分量的大幅提高(与平尾墩相比)。文中提出的水面壅高程度可为工程中闸门铰链支座的布置提供参考,闸室出口速度定量分析有助于深入理解宽尾墩抛射水流在空中纵向与竖向扩散的成因。

Hydraulics of Flow in Gate Chamber with X-shaped and Y-shaped Flaring Gate Piers

The distributions of hydraulic parameters in the gate chamber change due to flaring gate piers(FGPs).The variations in water level and velocity were analyzed quantitatively using RNG k-ε turbulent model.The extent of water level rising on side walls with X-shaped FGP increased from zero to 0.2 during the first 75% of gate chamber,and it grown rapidly during the last 25%.The extent of water level rising with Y-shaped FGP was slightly higher than that with X-shaped and the difference rised during the last 25% of gate chamber.The FGP decreased the velocity gradient in the middle part of gate chamber and the Y-shaped FGP impacted the gradient stronger than X-shaped.FGPs made changes for both the direction and magnitude of velocity in the outlet.The distribution of velocity assumed extremely non-uniform,especially the significant change of direction and the great increase in the horizontal velocity(compared to ordinary pier).The extent of water level rising is a reference for the arrangement of hinge supports,and the quantitative analysis on the velocity is helpful for understanding the longitudinal and vertical developments of flow.