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.

该提案涉及多孔介质/湍流界面处的交换过程。我们专注于流淌区的流动和质量传递，其中流淌的地表水和地下水混合。该区域对地表水的生态功能具有重大贡献。我们打算对由不同雷诺数的随机填充球体组成的多孔床上的湍流进行直接数值模拟。在这些模拟中，将解决孔隙空间问题。我们涵盖了从平稳到完全粗糙的湍流政权的范围。应借助最近发布的使用最先进的实验技术进行的实验数据来验证模拟，从而提供湍流量的详细测量。我们扩展了实验中可用的雷诺数范围，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重平均方法提供湍流动量和质量传输的详细信息。后者将用于区分最上层（布林克曼）中的时间平均流动引起的传输和湍流波动引起的传输。我们希望这些模拟能够提供有助于模拟潜流区质量和动量传递的重要信息，该信息适用于多孔介质和湍流之间的其他界面。