用于任意非球形颗粒受阻沉降全解析模拟的可扩展OpenLB-LAMMPS框架
A Scalable OpenLB LAMMPS Framework for Fully Resolved Simulations of Hindered Settling of Arbitrary Non-Spherical Particles
AI总结：
该研究开发了耦合OpenLB与LAMMPS的可扩展FSI框架，模拟含最多10万立方体的系统沉降，发现立方体与球形颗粒沉降差异，为大规模颗粒流模拟提供鲁棒工具。
AI中文摘要：
非球形颗粒的受阻沉降因解析复杂接触力学与流体动力学相互作用的计算挑战，相较球形颗粒仍远未被充分理解。本文提出一种可扩展的流固耦合（FSI）框架，将开源格子玻尔兹曼方法（LBM）软件OpenLB与LAMMPS中实现的离散元方法（DEM）耦合，以模拟流体中任意形状的刚体。颗粒接触通过DEM中的多球“团块”表示捕获，而颗粒几何则通过体素化在流体网格上解析。我们针对单颗粒和多颗粒基准对模型进行验证，进而研究最多含100000个立方体的系统中立方体的受阻沉降。模拟显示，立方体沉降与球形颗粒存在显著差异：立方体形成明显的配位壳，且无面平行接触，这与球形颗粒中观察到的接触主导型聚集形成对比。结果表明，即使在研究的最大系统中，速度波动的相关长度仍随系统尺寸缩放。这些发现凸显了颗粒形态在悬浮液动力学中的作用，并展示了一种用于模拟大规模岩土与颗粒流的鲁棒框架。
英文摘要：
Hindered settling of non spherical particles remains significantly less understood than spherical particles due to the computational challenges in resolving the complex contact mechanics and hydrodynamic interactions. In this paper, we present a scaleable fluid structure interaction (FSI) framework coupling the open-source LBM software in OpenLB with the Discrete Element Method (DEM) implemented in LAMMPS to simulate arbitrary shaped rigid bodies in a fluid. Particle contacts are captured using a multi-sphere "clump" representation in DEM, while particle geometries are resolved on the fluid grid via voxelization. We validate our model against single and multi-particle benchmarks, and proceed to study the hindered setttling of cubes in systems containing upto 100,000 cubes. Our simulations show distinct differences between the settling of cubes and sphere, as cubes form pronounced coordination shells without face-parallel contact, in contrast to the contact-dominated clustering observed in spheres. Our results find that correlation length in velocity fluctuations scale with system size even for the largest system studied. These findings highlight the role of particle morphology in suspension dynamics and demonstrate a robust framework for simulating large-scale geotechnical and particulate flows.
