A numerical study of sheet flow driven by velocity and acceleration skewed near-breaking waves on a sandbar using SedWaveFoam
A numerical study of sheet flow driven by velocity and acceleration skewed near-breaking waves on a sandbar using SedWaveFoam
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使用 SedWaveFoam 对沙洲上由速度和加速度倾斜的近破碎波驱动的面流进行数值研究
DOI：
10.1016/j.coastaleng.2019.103526
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发表时间：
2019
影响因子：
4.4
通讯作者：
Cox, Daniel
中科院分区：
文献类型：
--
作者：
Kim, Yeulwoo;Mieras, Ryan S.;Cheng, Zhen;Anderson, Dylan;Hsu, Tian-Jian;Puleo, Jack A.;Cox, Daniel
最近在OpenFOAM框架中开发了一种新的方法，能够同时解决整个水柱的自由表面波场，底部边界层和沉积物输运过程，称为SedWaveFoam。在这项研究中，SedWaveFoam使用近破波驱动的片流的大型波浪水槽数据进行了验证。获得了良好的协议自由面高程，流速，湍流动能，泥沙浓度，和片流泥沙通量。模型结果被用来调查的联合影响的速度偏态，加速度偏态，和前进波流片流输沙。将SedWaveFoam结果与刚盖一维垂直模型结果进行对比，以隔离自由表面的影响。由于自由表面的存在，通过前进波流动，岸上定向近床流速和泥沙通量增加。然而，增强净岸上输沙的近破碎的条件下，高速度和加速度偏度是几个因素大于在非破碎条件下，只有高速度偏度。模型结果表明，大的水平压力梯度，其中有一个Sleath参数超过0.2，可能起着关键作用。通过片流层的近床不稳定性来识别瞬时床面破坏，并与大的床面剪应力和水平压力梯度相关。近床不稳定引起的瞬时近床涡对应于波峰期间水平孔隙水压力梯度的增加，与实测数据一致。模型间的比较表明，一个二维模型是至关重要的捕捉瞬间床故障，增加沉积物悬浮在波峰通道和净陆上泥沙运输的影响。
A new methodology capable of concurrently resolving free surface wave field, bottom boundary layer, and sediment transport processes throughout the entire water column was recently developed in the OpenFOAM framework, called SedWaveFoam. In this study, SedWaveFoam is validated with large wave flume data for sheet flow driven by near-breaking waves. Good agreements are obtained for free surface elevation, flow velocity, turbulence kinetic energy, sediment concentration, and sheet flow sediment fluxes. Model results are used to investigate the joint effects of velocity skewness, acceleration skewness, and progressive wave streaming on sheet flow sediment transport. SedWaveFoam results are contrasted with rigid-lid one-dimensional-vertical model results to isolate the effect of the free surface. Onshore directed near-bed flow velocity and sediment flux are enhanced due to the presence of the free surface via progressive wave streaming. However, the enhancement of net onshore sediment transport for the near-breaking condition with both high velocity and acceleration skewness is several factors greater than that found in the nonbreaking condition with only high velocity skewness. Model results suggest that the large horizontal pressure gradient, which has a Sleath parameter exceeding 0.2, may play a key role. Momentary bed failure is identified via near-bed instability of the sheet flow layer, associated with a large bed shear stress and horizontal pressure gradient. Instantaneous near-bed vortices due to the near-bed instability correspond to the increase of horizontal pore pressure gradient during the wave crest, consistent with measured data. Model inter-comparison suggests that a two-dimensional model is crucial to capture the effect of momentary bed failure that increases sediment suspension during wave crest passage and net onshore sediment transport.
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影响因子：
--
作者：
Marjolein Dohmen-Janssen;D. Hanes
通讯作者：
Marjolein Dohmen-Janssen;D. Hanes
通过视频获得溃坝驱动冲刷中的近河床和席状流沉积物颗粒速度
DOI：
--
发表时间：
2017
期刊：
影响因子：
--
作者：
J. Puleo;Douglas R. Krafft;José Carlos Pintado;B. Bruder
通讯作者：
B. Bruder
沙洲顶斜非对称波作用下床质荷载和悬荷载对泥沙输移的相对贡献
DOI：
--
发表时间：
2019
期刊：
Journal of Geophysical Research: Oceans
影响因子：
--
作者：
R. Mieras;J. Puleo;Dylan L. Anderson;T. Hsu;D. Cox;J. Calantoni
通讯作者：
J. Calantoni
影响因子：
4.4
作者：
A. Reniers;E. Thornton;T. Stanton;J. Roelvink
通讯作者：
A. Reniers;E. Thornton;T. Stanton;J. Roelvink
波浪作用下水平压力梯度对河床失稳的影响
影响因子：
3.7
作者：
C. Berni;H. Michallet;E. Barthélemy
通讯作者：
E. Barthélemy