Flow and transport at an interface between a turbulent flow and a porous medium

湍流与多孔介质之间界面的流动和传输

• 批准号: 403236141
• 负责人: Professor Dr.-Ing. Michael Manhart
• 金额: --
• 依托单位: Professur für Hydromechanik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/403236141?language=en
• 关键词: Flow; transport; interface; between; turbulent

This proposal deals with the exchange processes at a porous media/turbulent flow interface. We concentrate on the flow and mass transfer in the hyporheic zone in which streamborne surface waters and subsurface waters mix. This zone has a significant contribution to the ecological functioning of surface waters. We intend to perform Direct Numerical Simulations of the turbulent flow over a porous bed consisting of randomly packed spheres at various Reynolds numbers. In these simulations the pore space will be resolved. We cover the range from smooth to fully rough turbulent regimes. The simulations shall be validated with the help of recently published data from an experiment using state-of-the art experimental techniques thus providing detailed measurements of turbulent flow quantities. We extend the range of Reynolds numbers available from the experiment and perform additional simulations of the mass transfer over the interface. This will enable us to provide detailed information of turbulent momentum and mass transport by adopting a double-averaged approach. The latter will be used to distinguish between transport due to the time-averaged flow in the upper-most (Brinkman) layer and transport due to turbulent fluctuations. We hope that these simulations will provide essential information helpful for modelling mass and momentum transfer in the hyporheic zone that is applicable to other interfaces between porous media and turbulent flows.

本文讨论了多孔介质/湍流界面上的交换过程。我们集中在潜流区的流动和质量传递，其中地表沃茨和地下沃茨混合。这一地带对地表沃茨的生态功能有重大贡献。我们打算进行直接数值模拟的湍流在多孔床组成的随机填充球在不同的雷诺数。在这些模拟中，将解析孔隙空间。我们涵盖了从光滑到完全粗糙的湍流制度。应借助最新公布的实验数据，使用最先进的实验技术对模拟进行验证，从而提供湍流量的详细测量。我们扩展了实验中的雷诺数范围，并对界面上的传质进行了额外的模拟。这将使我们能够通过采用双平均方法提供湍流动量和质量输运的详细信息。后者将被用来区分运输由于时间平均流在最上层（Brinkman）和运输由于湍流波动。我们希望，这些模拟将提供重要的信息，有助于建模的质量和动量传递在潜流区，适用于多孔介质和湍流之间的其他接口。