Fluid-driven granular transport is involved in many important geomorphological processes and industrial applications such as unconventional hydrocarbon recovery. Yet it remains challenging to fully understand the granular transport mechanisms in confined geometries. By performing simulations based on a coupled computational fluid dynamics and discrete element method (CFD-DEM) approach, we systematically investigate the particle transport patterns and mechanisms driven by fluid flow between two parallel plates. Depending on the local drag force, the particles can settle or suspend in the fluid, leading to fluid-driven particle transport by creeping or by suspension. In the case of settle particle layers, fluid velocity variation in the vertical direction contributes to the relative motion between particle layers. Fluid-induced fingering patterns are observed in the upper layer of settled particles during the sliding. It is shown that the average finger length increases linearly with time and is affected by the flow rate and particle volume fraction. Increasing the flow rate shift the particle migration from creeping and sliding to suspension, which generally improves the particle transport efficiency. The obtained understanding of particle transport patterns in the confined geometries may have practical implications for industrial scenarios such as proppant transport in hydraulic fractures and sand production in extraction systems.

流体驱动的颗粒运输涉及许多重要的地貌过程和工业应用，例如非常规的烃采收。然而，要完全了解受限几何结构中的颗粒传输机制仍然充满挑战。通过执行基于耦合的计算流体动力学和离散元素方法（CFD-DEM）方法的模拟，我们系统地研究了由两个平行板之间的流体流动驱动的颗粒传输模式和机理。取决于局部阻力，颗粒可以沉降或悬浮在流体中，从而通过蠕变或悬浮而导致流体驱动的颗粒传输。在沉降颗粒层的情况下，垂直方向上的流体速度变化有助于颗粒层之间的相对运动。在滑动过程中，在沉降颗粒的上层中观察到了流体诱导的指状图样。结果表明，平均手指长度随时间线性增加，并受流速和颗粒体积分数的影响。增加流速会使颗粒迁移从蠕变和滑动转移到悬浮，这通常会提高颗粒传输效率。对受限几何形状中的颗粒传输模式的了解可能对工业场景具有实际意义，例如水力压裂中的支撑剂传输和提取系统中的出砂。增加流速会使颗粒迁移从蠕变和滑动转移到悬浮，这通常会提高颗粒传输效率。对受限几何形状中的颗粒传输模式的了解可能对工业场景具有实际意义，例如水力压裂中的支撑剂传输和提取系统中的出砂。增加流速会使颗粒迁移从蠕变和滑动转移到悬浮，这通常会提高颗粒传输效率。对受限几何形状中的颗粒传输模式的了解可能对工业场景具有实际意义，例如水力压裂中的支撑剂传输和提取系统中的出砂。