Hydrodynamic modelling of tidal-fluvial flows in a large river estuary
Hydrodynamic modelling of tidal-fluvial flows in a large river estuary
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大河口潮汐河流的水动力模拟
DOI：
10.1016/j.ecss.2018.06.023
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Sandbach S
中科院分区：
文献类型：
--
作者：
Sandbach S
河流和河口环境之间的转变的特点是在本文中称为潮汐影响河流带(TIFZ)的区域内从单向水流转变为双向水流。为了加深我们对该带的水动力和地貌动力学的了解，我们对美国哥伦比亚河河口(CRE)潮汐影响河流带进行了场和数值模拟研究。中铁铁路很大，长40 公里，宽5至10 公里。在二维和三维构型中应用了浅水模型(Delft3D)，研究了模型对关键工艺参数的敏感性。我们的结果表明，在河口内约束的二维模型可以很好地再现分层河口TIFZ内的深度平均水流。模型结果突出了潮汐、河流和地形强迫之间的相互作用，从而导致了随深度变化的潮汐整流，从而形成了剩余泥沙输移区：i)可能是沿浅滩边缘和沙洲背风处的洪水导向区，同时ii)是较深的航道低潮区的落潮导向区。这种情况在流量较少时增强，但河流流量增加会减少具有洪水导向泥沙净输移和流量的区域的数量和大小。这些泥沙运移模式提供了一种机制，将沙洲/岛屿地形向下游延伸，并在同一航道内产生洪水导向、退潮导向和对称的河床。对模型数据的分析表明，洪水导向的泥沙输移是由潮汐变化和平均流量共同作用的。这些结果突出表明，在考虑TIFZ的长期地形动力学演变时，需要考虑平均流分量(M0)。
The transition between riverine and estuarine environments is characterised by a change from unidirectional to bidirectional flows, in a region referred to herein as the Tidally-Influenced Fluvial Zone (TIFZ). In order to improve our understanding of the hydrodynamics and morphodynamics of this zone, we present a combined field and numerical modelling study of the Columbia River Estuary (CRE), USA, tidally-influenced fluvial zone. The CRE is large measuring 40 km in length and between 5 and 10 km wide. A shallow water model (Delft3D) was applied in both 2D and 3D configurations and model sensitivity to the key process parameterizations was investigated. Our results indicate that a 2D model constrained within the estuary can sufficiently reproduce depth-averaged flow within the TIFZ of a stratified estuary.Model results highlight the interactions between tidal-, fluvial- and topographic-forcing that result in depth dependent tidal rectification, and thus zones of residual sediment transport that: i) may be flood-directed along shallow channel margins and in the lee of bars, and simultaneously ii) is ebb-directed within deeper channel thalwegs. This condition is enhanced at lower discharges, but increased fluvial discharge reduces the number and size of regions with net flood-directed sediment transport and flow. These sediment transport patterns provide a mechanism to extend the bar/island topography downstream, and generate flood-directed, ebb-directed, and symmetrical bedforms, all within the same channel. Analysis of the model data reveals flood-directed sediment transport is due to both tidal variability and mean flow. These results highlight the need to include the mean flow component (M0) when considering the long-term morphodynamic evolution in a TIFZ.
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圣劳伦斯河流口的水动力模型。
DOI：
10.1061/(asce)ww.1943-5460.0000394
发表时间：
2017
期刊：
Journal of Waterway Port Coastal and Ocean Engineering-asce
影响因子：
--
作者：
P. Matte;Y. Secretan;J. Morin
通讯作者：
J. Morin
影响因子：
3.3
作者：
Daniel R. Parsons;P. R. Jackson;J. Czuba;F. Engel;B. Rhoads;Kevin A. Oberg;James L. Best;David S. Mueller;Kevin K. Johnson;James D. Riley
通讯作者：
Daniel R. Parsons;P. R. Jackson;J. Czuba;F. Engel;B. Rhoads;Kevin A. Oberg;James L. Best;David S. Mueller;Kevin K. Johnson;James D. Riley
影响因子：
2.3
作者：
Baptista, AM;Zhang, YL;Turner, PJ
通讯作者：
Turner, PJ
影响因子：
2.2
作者：
Chien Pham Van;Benjamin de Brye;É. Deleersnijder;A. Hoitink;M. Sassi;B. Spinewine;H. Hidayat;S. Soares-Frazão
通讯作者：
Chien Pham Van;Benjamin de Brye;É. Deleersnijder;A. Hoitink;M. Sassi;B. Spinewine;H. Hidayat;S. Soares-Frazão
DOI：
10.2307/1352614
发表时间：
1997
期刊：
Estuaries
影响因子：
--
作者：
D. Bowers;A. Al
通讯作者：
A. Al