基于Fluent二维流体仿真模块的调水工程分汊口处防淤研究

Research on Silt Prevention at the Branching Estuaries of Water Transfer Project Based on Fluent Two-dimensional Fluid Simulation Module

为解决长距离调水工程分汊口处泥沙淤积问题,在分汊口附近适当位置布设弧形翼墙水工建筑物,并在翼墙处形成弯道。基于弯道绕流原理,改变分汊口附近流速分布规律,使较高流速水流对分汊口处形成冲淤,从而达到改善该区域泥沙淤积问题。利用Fluent二维流体仿真模块,对12种工况分别从有无弧形翼墙、干渠与分渠夹角、弧形翼墙布置位置、干渠流速对分汊口处的防淤情况影响进行试验对比。结果表明,相同工况条件下,在分汊口附近合理位置布设弧形翼墙、增大干渠流速均能很好地改善分汊口附近的流场分布,从而达到改善淤积效果;干渠与侧渠夹角对分汊口附近流场变化影响不明显;只有在合理位置设置弧形翼墙才能显著改善流场分布。该结果为治理和缓解分汊口处泥沙淤积提供了一个新的方法。

In order to solve the problem of sediment deposition at the branch mouth of the long-distance water transfer project,the curved wing wall hydraulic structure was arranged at an appropriate position near the branch mouth,and a curve was formed at the wing wall.Based on the principle of flow around the bend,the distribution law of the flow velocity near the branch mouth was changed,and the water flow with higher flow velocity formed the scouring and silting at the branch mouth so as to improve the sediment deposition problem in this area.The Fluent two-dimensional fluid simulation module was used to simulate 12 working conditions,and the influences of the presence or absence of the arc wing wall,the angle between the main channel and the branch channel,the location of the arc wing wall,and the flow rate of the main channel on the silt prevention situation at the branch mouth were compared.The results show that under the same working conditions,arranging the arc-shaped wing wall at a reasonable position near the branch mouth and increasing the flow velocity of the main channel can well improve the flow field distribution near the branch mouth,thereby achieving the effect of improving sedimentation;The included angle between the main channel and the side channel has no obvious impact on the change of the flow field near the branch mouth;Only setting the arc-shaped wing wall at a reasonable position can significantly improve the flow field distribution.The results provide a new method for controlling and alleviating sediment deposition at the branch mouth.