不同格栅布置对消力池池长影响研究

Influence of Different Grid Layouts on Length of Stilling Pool

通过水工模型试验,研究铅直格栅和Γ形格栅在一定开孔率条件下,位置变化对底流消力池水力特性的影响。结果表明:铅直格栅能够降低过栅水流动能,但栅前上涌水突现象极为严重;改进后的Γ形格栅能够兼顾格栅前后水流流态,在池深受限条件下,有效降低消力池池长;格栅靠近消力池进口布置,对射流动能衰减作用最大,能最大程度降低池长,但栅前上涌水突依然明显,也恶化了格栅受力条件;格栅靠近消力池出口布置,消力池内水力特性刚好和前述情况相反,但池长不足;格栅布置于消力池中部位置,既可以利用栅前水体消减入射水体能量,也可以降低跃后断面水深,在一定池长条件下,实现和下游水流的平顺衔接。

Through the hydraulic model test,the influence of the position change of the vertical grid and theΓ-shaped grid on the hydraulic characteristics of the underflow stilling pool under a certain opening rate is studied.The results show that the vertical grid can reduce the flow energy of the water passing the grid,but the phenomenon of water gushing up in front of the grid is extremely serious;the improvedΓ-shaped grid can take into account the flow patterns of the water before and after the grid,and it is effective under the condition of limited pool depth in reducing the length of the stilling pool;The grid is placed close to the entrance of the stilling pool,which has the greatest effect on the attenuation of jet flow energy and can minimize the pool length,but the water gushing up in front of the grid is still obvious,which also deteriorates the force conditions of the grid;The grid is arranged close to the exit of the stilling pool,the hydraulic characteristics in the stilling pool are just opposite to the previous situation,but the pool length is insufficient;The grid is arranged in the middle of the stilling pool,which can use the water in front of the grid to reduce the incident water energy,and it is also objectively effective inlowering the water depth of the cross-section after the jump,and the smooth connection with the downstream water flow is realized under the condition of a certain pool length.