波浪作用下沙纹床面底层流动特性研究

Study on wave bottom boundary layers over a rippled bed

涡动沙纹很大程度决定着床面阻力和波浪衰减,针对涡动沙纹作用下的绕流结构具有强二维特性,建立了立面二维曲线坐标下的数值模型。利用国外公开发表的试验数据进行验证,表明模型能模拟波浪作用下底层分离涡随时间、空间变化的动力特性,对底层流动的紊动特性、床面剪切应力的随时间、空间的变化以及涡动结构的尺度分别进行了讨论。

Vortex ripple is widely formed in the coastal region, and the dynamics of vortex is responsible for the sediment transport In this paper, a 2D LargeEddySimulation method (LES) was used to predict the flow structure and the dynamics of vortex in the bottom layers under the action of the wave. The numerical simulation results show a complete process of vortex formation, evolvement and disappearance. The bed shear stress distribution and the length of the separation bubble with different scale vortex ripple also were studied