基于水平集-离散元方法的球谐函数颗粒材料缓冲性能分析

在自然环境与工业领域中,颗粒材料是一种常见的缓冲材料,其中大量形态各异的非球形颗粒表现出复杂的力学特性并应用于不同工程领域。本文采用球谐函数构造不同球面度和表面凹凸特性的非规则颗粒,通过水平集方法计算球谐函数颗粒间的接触点和碰撞力,并对冲击过程中球形和凹形颗粒的缓冲性能进行离散元分析。数值结果表明,颗粒床厚度、冲击速度和颗粒形状显著影响球谐函数颗粒材料的缓冲性能。颗粒床底部的冲击力峰值随着颗粒床厚度和表面凹凸性的增加而降低,同时冲击力峰值随着冲击速度和颗粒球面度的增加而增加。与球形颗粒相比,球谐函数颗粒具有凹凸表面和多接触点特性,这有利于冲击荷载向四周扩展并提高凹形颗粒的缓冲效果。

Analysis of buffering capacity of spherical harmonic granular materials based on the level set-discrete element method

Granular material is a common buffer material in nature and industry,and a large number of non-spherical particles with different morphologies exhibit complex mechanical properties and are used in different engineering fields.In this paper,irregularly shaped particles with different sphericity and surface concavity characteristics are constructed using spherical harmonic functions,and the contact points and collision forces between spherical harmonic particles are calculated by the level set method.Subsequently,the discrete element method is used to analyze the buffering capacity of spherical and concave-shaped particles during impact processes.The numerical results show that the granular bed thickness,impact velocity and particle shape significantly affect the buffering capacity of the spherical harmonic granular materials.The impact load peaks at the bottom of the granular bed decrease with increase of the granular thickness and surface concavity,while the impact load peaks increase with increase of the impact velocity and particle sphericity.Compared with spherical particles,spherical harmonic particles have concave-convex surfaces and multiple contact characteristics,which facilitate the expansion of impact loads in three directions and improve the buffering capacity of concave particles.