标题： 排水过程中颗粒多孔介质中角部与主体流动的相互作用 显示英文标题

标题： Interaction between corner and bulk flows during drainage in granular porous media

摘要： 多孔介质中的排水可以分解为两种主要机制：通过孔体和喉道主体的界面的一次性塞状位移，以及在入侵前沿之后的角落和薄膜中的二次缓慢流动。 在颗粒多孔介质中，这种二次排水机制在由液滴簇之间形成的pendular结构（如毛细管桥和液环）的连通路径中展开。 为了表示这两种机制，我们提出了一个动态双网络模型用于排水，考虑到气体从准二维颗粒多孔介质中驱替润湿液体。 对于该模型，专门分析了毛细管桥的形状和水力传导性，以便在有限速度下正确量化二次排水机制。 利用该模型，对排水过程中润湿相的连通性和流动进行了研究，涵盖了广泛的流动条件。 结果表明，非饱和区域中液相连接结构的跨度以及它们对流动的贡献能力，随着毛细管数和Bond数的变化而显著不同。 显示英文摘要

摘要： Drainage in porous media can be broken down into two main mechanisms: a primary piston-like displacement of the interfaces through the bulk of pore bodies and throats, and a secondary slow flow through corners and films in the wake of the invasion front. In granular porous media, this secondary drainage mechanism unfolds in connected pathways of pendular structures, such as capillary bridges and liquid rings, formed between liquid clusters. To represent both mechanisms, we proposed a dynamic dual-network model for drainage, considering that a gas displaces a wetting liquid from quasi-2D granular porous media. For this model, dedicated analyses of the capillary bridge shapes and hydraulic conductivity were conducted so that the secondary drainage mechanism could be properly quantified at finite speeds. With the model, an investigation of the wetting-phase connectivity and flow during drainage was carried out, covering a broad range of flow conditions. Results indicate that the span of liquid-connected structures in the unsaturated region, as well as their ability to contribute to flow, varies significantly with Capillary and Bond numbers.