竖缝式鱼道细部结构改进研究

摘要

本文针对鱼道细部结构进行改进研究,提出了流线型墩头的布置型式.采用数值模拟的方法对不同墩头型式的鱼道进行水力特性对比分析,并对流线型墩头的鱼道进行试验研究.结果表明:与折线型墩头相比,流线型墩头不会导致鱼道水池内水流结构的显著改变;主流横向偏转程度有所减缓,横向扩散加大,有利于主流流速的沿程衰减;而竖缝控制断面局部水头损失减少,需采用较小的鱼道底坡以控制竖缝断面流速.鉴于流线型墩头能避免折线型墩头对上溯鱼类可能造成的物理伤害,条件允许时可考虑采用.%Aiming at the improvement of head of baffle in the vertical slot fishways,the layout of a streamlined head of baffle is presented.The hydraulic characteristics in fishways with different baffle types is analyzed using numerical simulation method and the hydraulic experiment is performed for the fishway with streamlined head of baffle.The results indicates that under the premise that the aspect ration,width of vertical slot and other constraints in regular pools are established,the streamlined head baffle has no significant effect on the flow structures in the fishway pools,and the transversal diffusion of the mainstream increases while the deflection of mainstream slows down.Therefore,it is beneficial to the attenuation of the velocity in the mainstream.The research also indicates that the local head loss is reduced,so it is necessary to adopt small bottom slope to control the velocity at the slot.The streamlined head baffle could avoid physical damages to fish effectively,while it is serious when the broken-line head baffle is adopted.The layout of streamlined head baffle has unique technical advantages,so when conditions permit,the layout of streamlined head baffle may be considered to use it in the hydraulic design.