波流作用下沙纹床面悬沙运动的高效数值模型  

EFFICIENT NUMERICAL MODEL FOR SUSPENDED SEDIMENT TRANSPORT OVER RIPPLED BED UNDER WAVE-CURRENT ACTIONS

作　　者：周游 侯新妤 施华斌 陈鑫[1] Zhou You;Hou Xinyu;Shi Huabin;Chen Xin(College of Water Resources and Civil Engineering,China Agricultural University,Beijing 100083,China;State Key Laboratory of Internet of Things for Smart City,University of Macao,Macao 999078,China)

机构地区：[1]中国农业大学水利与土木工程学院,北京100083 [2]澳门大学智慧城市物联网国家重点实验室,中国澳门999078

出　　处：《力学学报》2025年第2期453-463,共11页Chinese Journal of Theoretical and Applied Mechanics

基　　金：国家自然科学基金(12472415和41961144014);澳门特别行政区科学技术发展基金(0050/2020/AMJ)资助项目。

摘　　要：沙纹床面旋涡运动和泥沙输运对海岸地貌演变有着重要影响,但传统数值模型忽略了非线性波-流相互作用、泥沙相位差等重要因素.文章在保证精度的基础上降低计算成本,发展了一个高效的波流共同输运悬沙的数值模型,并探究了沙纹床面水动力及悬沙运动规律.悬沙方程综合了惯性及尾涡对颗粒紊动扩散的相反作用;泥沙近底条件统合了非线性波的加速度-边界层非对称效应和波流相互作用,泥沙的相位差和质量守恒效应.本文用系列波流共同作用下的沙纹实验验证了模型适用性,进一步对比了恒定流、波浪往复流和波流共同作用的沙纹水动力和悬沙运动.结果表明,波浪的存在增加了紊流黏度,动量交换机制使得表观粗糙高度比实际粗糙高度大很多,从而改变了流的速度对数分布律.流的存在主要影响波峰以上波浪的水平流速,影响了对称往复流泥沙通量在正负半周期的对称性,从而产生净输沙.该高效数值模型可用于海域复杂波流动力条件下沙纹的数值计算,可为港口、海岸及近海工程的规划和建设提供科学指导.Vortex motion and sediment transport over rippled beds greatly impact coastal geomorphology,but traditional numerical models ignore important factors such as nonlinear wave-current interaction and phase-lag.The two-phase model involves complex calculations for particle collision stress,friction stress,and interphase forces,and the applications of the Lagrangian model are limited by particle size and number of particles.To minimize computational costs while ensuring accuracy,an efficient numerical model for sediment transport was developed,and the hydrodynamics and suspended sediment motion above the rippled bed under wave-current actions were explored.The efficient advection-diffusion sediment numerical model incorporated the impacts of particle inertia and wake flow around particles.The asymmetric development of boundary layer,acceleration effect,phase-lag,and mass conservation of sediment under the influence of nonlinear waves were incorporated into the bottom boundary condition for sediment.To accurately solve the flow with inverse pressure gradient above the rippled bed,the Reynolds stress was closed by the shear stress transport(SST)k-ωturbulence model.The model was verified by a series of experiments,and hydrodynamics and suspended sediment motion were studied above rippled beds under actions of current,wave,and wave-current flow.The results were as follows.(1)Compared to the wave oscillatory flow,the addition of current primarily affected the horizontal velocity above the ripple crest,while the flow below the ripple crest was still influenced by the periodic vortex structure.The positive(anticlockwise)vortex formed on the left side of the ripple moved further in the horizontal direction;the size and strength of the negative(clockwise)vortex formed on the right side of the ripple increased.The negative vortex had a longer duration and extended further on the right side,and after being thrown to the left side of the ripple,its horizontal movement distance was shorter.(2)Compared to the current flow,the pres

关 键 词：波流共同作用 涡动沙纹 相位差 惯性及尾涡 泥沙近底条件 

分 类 号：TV142[水利工程—水力学及河流动力学]