组合隔板式鱼道水力特性数值模拟研究

鱼道是为鱼类提供洄游通道的一种重要的工程措施。基于Flow-3D采用标准RNG k-ε紊流模型和Tru-VOF追踪自由液面方法,对鱼道池室内流场进行三维紊流数值模拟,研究池室内水流流速、流态空间分布,分析鱼道的水力特性对目标鱼类洄游上溯的影响。结果表明:溢流堰与竖缝组合隔板式鱼道在设计流速v=0.75 m/s条件下,竖缝处平均流速为0.83 m/s,竖缝处流速分布范围为0.76~0.89 m/s;堰上流速为0.90~1.12 m/s,回流区流速分布范围为0.09~0.25 m/s,流速大小在鱼类的克流能力范围之内,但靠竖缝隔板处存在明显的主流贴壁现象。为此开展了池室优化方案设计,使鱼道池室流态满足鱼类上溯要求。

Numerical Simulation of Hydraulic Characteristics of Combined Baffle Type Fishway

Fishway is an important engineering measure for fish migration. In this paper, 3D turbulence numerical simulation of the flow field in fishway pool was carried out using standard RNG k-ε turbulence model and Tru-VOF tracking free liquid level method based on Flow-3D. The spatial distribution of flow velocity and flow pattern in fishway pool was studied, and the influence of the hydraulic characteristics of fishway on the upstream migration of target fish was analyzed. Results show that in the overflow weir combined with vertical slot fishway at design velocity (v=0.75 m/s), the average flow velocity at slot was 0.83 m/s (ranging between 0.76 m/s and 0.89 m/s), the flow velocity above weir was from 0.90 m/s to 1.12 m/s, and the velocity in backflow zone was in the range of 0.09-0.25 m/s, all within the limits of fish swimming ability. Nevertheless, in the adjacent of the slot baffle, the main stream obviously adhered to the wall. The design of fishway pool was optimized to meet the upstreaming requirements of fish.