颗粒聚合体碰撞破损的细观力学仿真研究

粉末和颗粒材料常常以聚合体(agglomerate,还可译成结块, 聚团等)的形式存在.无论是自然环境中还是工业处理过程中, 微小颗粒聚合体碰撞破损是一常见物理现象.近十几年来, 对颗粒聚合体碰撞研究在试验和数值模拟方面均取得了很大的进展.特别是利用颗粒离散元方法, 结合经典接触力学理论, 对微米颗粒聚合体碰撞破损的细观力学机理进行的研究, 取得了很多重要成果.基本形成了较为完善的模拟分析方法, 提出了许多新概念, 形成了目前适于分析研究的专用分析程序.本文介绍了目前国际上颗粒聚合体碰撞破损模拟研究的一般方法和理论, 总结了现有的主要研究内容及成果, 并提出一些研究展望. 

MICROMECHANICS STUDY ON AGGLOMERATE IMPACT BREAKAGE

Particulate materials are often in the form of powders which are themselves agglomerations of much smaller primary particles.A common problem in the handling of powders is the degradation due to attrition and/or fragmentation of agglomerates as they collide with each other and with the process equipment.Impact breakage has been studied experimentally for many years.However,information from those experiments is normally restricted to post-impact examinations of the fragments and debris produced during the short duration of an impact event.Numerical simulations of agglomerate impact fracture,especially using discrete element method,have achieved great successes over the past decade.New theories based on modern contact mechanics and new concepts have been proposed to study the mechanism of agglomerate impact breakage.This paper gives a brief review on the current development of the research,and also describes the simulation techniques of agglomerate impact.