标题： 料仓填充过程中分层模式的尺度依赖性 显示英文标题

标题： Scale dependence of segregation patterns in the filling of silos

摘要： 颗粒流中的尺寸分离是一种众所周知的现象：实验室实验一致表明，在填充过程中大颗粒向筒仓壁迁移，而小颗粒则集中在中心区域。 矛盾的是，大规模工业筒仓的现场观测通常报告相反的模式，这挑战了这些发现。 我们通过一项系统实验研究明确了这些模式，该研究涵盖了准二维筒仓中双分散颗粒流的相关无量纲数，在干燥和浸没条件下，变化容器几何形状和流体粘度。 图像分析显示，观察到的模式由两个关键的无量纲参数控制：筒仓的细长比和斯托克斯数，后者概括了颗粒惯性与粘性阻力之间的平衡。 我们的结果展示了流体在分离动力学中的作用，并提供了一个统一的尺度框架，解决了空气中实验室尺度和现场尺度的观测差异。 显示英文摘要

摘要： Size segregation in granular flows is a well-known phenomenon: laboratory experiments consistently show that large particles migrate toward silo walls during filling, while smaller particles concentrate near the center. Paradoxically, field observations in large-scale industrial silos often report the opposite pattern, challenging these findings. We demarcate these patterns through a systematic experimental study spanning a range of dimensionless numbers relevant to bidisperse granular flows in quasi-2D silos under both dry and immersed conditions, varying container geometry and fluid viscosity. Image analysis reveals that the observed patterns are governed by two key dimensionless parameters: the slenderness of the silo and the Stokes number, which encapsulates the balance between particle inertia and viscous drag. Our results demonstrate the role of fluids on segregation dynamics and provide a unified scaling framework that reconciles laboratory- and field-scale observations in air.