Fundamental Understanding of Turbulent Flow over Fluid-Saturated Complex Porous Media

了解多孔介质上的湍流特性是揭示自然现象背后的物理学的核心（例如，土壤蒸发、森林和城市树冠、鸟类羽毛和河床）以及包括能源储存、流量/噪音控制、电子冷却、填充床核反应堆和金属泡沫热交换器在内的人造技术。在这些自然和工程应用中，在复合多孔流体系统中的湍流和传热的基本理解的一步变化，其中包括流体饱和的多孔介质和流通过它，是至关重要的表征和诊断分析这样的系统。复合系统的流动和热特性很大程度上取决于外部流动、下游尾迹和多孔介质中流体流动之间的相互作用。尽管这一问题在自然界和工程中具有明显的相关性和广泛的影响，但显然缺乏对复合多孔流体系统中湍流的流动和热特性的基本理解，以及将多孔区域和经过其的外部流体之间的流动和热特性的交换联系起来的模型。多孔介质上的速度和热边界层的特性，理解通过多孔介质的流动通道的控制机制，可能的流动泄漏及其与尾流的相互作用，以及它们与多孔介质的几何特性的关系，仍然是重大的科学挑战。这突出了对系统的基础研究的明确需求，旨在了解真实多孔介质上湍流的流动和热特性，以及多孔基质的性质，多孔介质内的流动和多孔区域上和通过多孔区域的湍流结构之间的关系。我们将曼彻斯特大学和南安普顿大学的计算和模拟专业知识与布里斯托大学的实验专业知识相结合，以获得对湍流边界层的基本理解，流动泄漏和下游尾迹对流体饱和多孔介质流动和热特性的影响。这将用于建立基于证据的界面流动和热模型，代表通过界面的两个区域之间的流动特性的交换。然后，这些模型将被用来开发一个设计工具的基础上的体积平均的方法，这是一个流行的低成本的工程方法，研究在多孔介质中的运输，为实际规模的应用程序中的孔隙规模的分析在计算上是禁止的。

Understanding of turbulent flow characteristics over porous media is central for unravelling the physics underlying the natural phenomena (e.g., soil evaporation, forest and urban canopies, bird feathers and river beds) as well as man-made technologies including energy storage, flow/noise control, electronics cooling, packed bed nuclear reactors and metal foam heat exchangers. In these natural and engineering applications, a step change in the fundamental understanding of turbulent flow and heat transfer in composite porous-fluid systems, which consists of a fluid-saturated porous medium and a flow passing over it, is crucial for characterisation and diagnostic analysis of such systems. Flow and thermal characteristics of the composite systems depends heavily on the interaction between the external flow, downstream wake, and the fluid flow in the porous media. Despite the clear relevance and wide-ranging impact of this problem in nature and engineering, there is a clear lack of fundamental understanding of the flow and thermal characteristics of turbulent flow in composite porous-fluid systems, and the models that relate the exchange of the flow and thermal properties between the porous region and the external fluid passing over it. In particular, the characterisation of the velocity and thermal boundary layers over the porous media, understanding the mechanisms governing flow passage through porous media, possible flow leakage and its interaction with the wake flow, as well as their relationship with the geometric characteristics of porous media, have remained major scientific challenges. This highlights the clear need for a systematic fundamental study aimed at understanding the flow and thermal characteristics of turbulent flow over realistic porous media and the relationship between the properties of porous substrate, the flow within the porous media and the structure of turbulent flow over and past the porous region.In this ambitious collaborative project, we combine the computational and modelling expertise at the University of Manchester and Southampton with the experimental expertise at the University of Bristol, to gain fundamental understanding of the turbulent boundary layer, flow leakage and downstream wake on the flow and thermal characteristics of fluid-saturated porous media. This will be used to establish evidence-based interface flow and thermal models, representing the exchange of flow properties between two regions through the interface. These models will then be used to develop a design tool based on the volume-averaged approach, which is a popular low-cost engineering approach for studying transport in porous media, for real-scale applications where the pore-scale analysis in computationally prohibitive.