基于CFD-DEM耦合方法的近床面水流泥沙运动模拟研究

Simulation of fluid-sediment particle motion near bed based on CFD-DEM coupling method

基于CFD-DEM方法,采用流体计算软件Open FOAM、颗粒运动模拟软件LIGGGHTS及CFDEM耦合库,建立流体—颗粒运动耦合模型,并利用模型研究不同水动力条件下近床面流体与颗粒的运动规律。模拟结果表明,模型能较好模拟近床面水流紊动特性及雷诺应力分布,也能较准确刻画出颗粒未起动、推移质输沙及推移质和悬移质共同输沙的三种状态,计算得到的推移质单宽输沙率与实验结果及经验公式吻合较好。

Based on CFD-DEM method, using computational fluid dynamics software OpenFOAM, particle mo-tion simulation software LIGGGHTS and CFDEM coupling library, a coupled fluid-particle model was developed and applied in the investigation of flow and particle near bed in different hydrodynamic conditions. The simulation results show that the coupled model has a good performance on describing turbulence intensity and the distribution of Reynold stress. For particle motion, this model can also depict well the three typical states of settled, bedload transport and bedload-suspended load transport. The simulated results of bedload discharge per unit have a good match with experimental data and empirical formula.