水下射流冲刷的CFD-DEM耦合模拟及射流参数优化研究OA

Numerical simulation of underwater jet-induced scour faces significant computational efficiency challenges due to the strong coupling of water-sediment multiphase flow,transient hydrodynamic behavior,and the discrete nature of sediment particles.To address this issue,this study employs a coupled Computational Fluid Dynamics and Discrete Element Method(CFD-DEM)approach to simulate the jet scouring process on a non-cohesive uniform sand bed.The simulations reveal strong correlations between scour performance and key physical parameters,including average shear stress,maximum shear stress,average shear velocity,maximum shear velocity,and average total pressure.Based on this finding,an innovative simplified strategy is proposed,which decouples the complex two-phase flow problem into a computationally more efficient simulation involving only single-phase water jet flow.Utilizing this strategy,the effects of key jet parameters—nozzle diameter,shape,and spacing—on scour efficiency are systematically investigated.The results indicate that,under the optimal nozzle spacing,square nozzle configurations,coupled with either increased flow rate or reduced diameter,significantly enhance the key physical quantities acting on the bed,thereby leading to improved scour performance.The proposed decoupled simulation method offers an efficient alternative for tackling underwater jet scour problems and opens new avenues for theoretical research and practical applications in related fields.