Topographic Effects on Lagrangian Residual Flow in Stratified Estuaries

地形对层状河口拉格朗日剩余流的影响

• 批准号: 8711790
• 负责人: David Jay
• 金额: $ 34.16万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-15 至 1991-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8711790&HistoricalAwards=false
• 关键词: Topographic; Effects; Lagrangian; Residual; Flow

The goal of this project is to provide a better understanding of the Lagrangian residual flow generated in shallow estuaries. Particles and solutes are carried with the Lagrandain velocity. Therefore, knowledge of the controlling mechanisms of the Lagrandain velocity is esstenial for the prediction of salinity and pollutant distributions. Both stratification and topography have strong effects on the Lagrangian residual flow. Because the two-layer flow in a strongly forced estuary is in a nearly critical (flood) or partially supercritical (ebb) internal hydraulic state, local topographic features (e.g., bends, bars and holes) with wave lengths of less than one tidal excursion have a strong effect on isopycnal displacement and vertical mixing, and therefore on Lagrangian drifts. Thus, the salinity and Lagrangian flow distribution, vertical exchange processes and esturine topography are all closely related. This three-year research project combines accurate, small-scale field measurements of flow over typical topographic features with computer modeling to determine the essential interactions. The models include turbulent mixing effects caused by stratified boundary layers and free shear layers.

该项目的目标是提供一个更好的 了解拉格朗日余流产生的， 浅水河口 颗粒和溶质随 拉格朗日速度。 因此，控制的知识 拉格朗日速度的机制是estesteivable为 盐度和污染物分布的预测。 两 分层和地形对 拉格朗日余流 因为在一个 强强迫河口处于近临界（洪水）或 局部部分超临界（退潮）内部水力状态 地形特征（例如，弯曲、钢筋和孔洞） 小于一次潮汐漂移的长度有很强的影响 等密度线位移和垂直混合，因此， 拉格朗日漂移。 因此，盐度和拉格朗日流 分布、垂直交换过程和河口 地形都是密切相关的。 这项为期三年的研究 该项目结合了精确的小规模实地测量， 典型地形上水流的计算机模拟 以确定基本的相互作用。 模型包括 分层边界层引起的湍流混合效应 和自由剪切层。