• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Ocean Dynamics >Contemporary hydrodynamics and morphological change of a microtidal estuary: a numerical modelling study
【24h】

Contemporary hydrodynamics and morphological change of a microtidal estuary: a numerical modelling study

机译：潮汐河口的当代水动力和形态变化：数值模拟研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Contemporary hydrodynamics and morphological change are examined in a shallow microtidal estuary, located on a wave-dominated coast (Port Stephens, NSW, Australia). Process-based numerical modelling is undertaken by combining modules for hydrodynamics, waves, sediment transport and bathymetry updates. Model results suggest that the complex estuarine bathymetry and geometry give rise to spatial variations in the tidal currents and a marked asymmetry between ebb and flood flows. Sediment transport paths correspond with tidal asymmetry patterns. The SE storms significantly enhance the quantities of sediment transport, while locally generated waves by the westerly strong winds also are capable of causing sediment entrainment and contribute to the delta morphological change. The wave/wind-induced currents are not uniform with flow over shoals driven in the same direction as waves/winds while a reverse flow occurring in the adjacent channel. The conceptual sediment transport model developed in this study shows flood-directed transport occurs on the flood ramp while ebb-directed net transport occurs in the tidal channels and at the estuary entrance. Accretion of the intertidal sand shoals and deepening of tidal channels, as revealed by the model, suggest that sediment-infilling becomes advanced, which may lead to an ebb-dominated estuary. It is likely that a switch from flood- to ebb-dominance occurs during the estuary evolution, and the present-day estuary acts as a sediment source rather than sediment sink to the coastal system. This is conflictive to the expectation drawn from the estuarine morphology; however, it is consistent with previous research suggesting that, in an infilling estuary, an increase in build-up of intertidal flats/shoals can eventually shift an estuary towards ebb dominance. Thus, field data are needed to validate the result presented here, and further study is required to investigate a variety of estuaries in the Australian area.
机译：在一个以波浪为主的海岸（澳大利亚新南威尔士州史蒂芬斯港）的浅潮汐河口中研究了当代的水动力和形态变化。通过组合流体动力学，波浪，泥沙输送和测深更新模块来进行基于过程的数值建模。模型结果表明，复杂的河口测深和几何形状会引起潮汐流的空间变化以及潮汐流和潮汐流之间的明显不对称性。泥沙输送路径与潮汐不对称模式相对应。 SE风暴极大地增加了泥沙的输送量，而西风强风在局部产生的波浪也能够引起泥沙夹带并有助于三角洲的形态变化。波浪/风感应的电流在沿与波浪/风相同的方向驱动的浅滩上流动时不均匀，而在相邻通道中发生逆流。在这项研究中开发的概念性泥沙输运模型表明，在洪水坡道上发生了洪水导向的输运，而在潮汐通道和河口入口处发生了退潮导向的净输运。如模型所揭示的，潮间带浅滩的积聚和潮汐通道的加深表明，沉积物的充填变得先进，这可能导致退潮为主的河口。在河口演变过程中，很可能会从洪水主导向退潮主导转变，而如今的河口起着沉积物来源的作用，而不是沉积物沉入海岸系统。这与从河口形态学得出的预期相矛盾；但是，这与以前的研究结果一致，即在河口充裕的情况下，潮间带/浅滩堆积的增加最终会使河口向退潮方向发展。因此，需要现场数据来验证此处提出的结果，并且需要进行进一步的研究以调查澳大利亚地区的各种河口。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号