【作者】 费明龙； 孙其诚；

【Author】 Minglong Fei;Sun Qicheng;Beijing Municipal Institute of City Planning and Design;State Key Laboratory of Hydroscience and Engineering,Tsinghua University;

【机构】 北京市城市规划设计研究院； 清华大学水沙科学与水利水电工程国家重点实验室；

【摘要】 颗粒流粒径分聚是在自然界和工业生产中都普遍存在的力学现象。学界对颗粒粒径分聚的机理已经开展了多年的研究,并提出了一系列有效的模型,如连续介质混合物理论模型,动理学理论模型等。前者适用于密实颗粒流态,后者则能有效刻画快速颗粒流动的分聚现象。针对各类模型适用的流态各不相同的问题,本文基于连续介质混合物理论Fan-Hill-Tan模型,通过考虑颗粒流流态转变对颗粒介质内部应力状态的影响,对Fan-Hill-Tan混合物理论模型进行了修正,将其运用范围扩展到快速颗粒流流态。进一步,本文使用物质点方法搭建了修正模型的数值模型,并使用该模型模拟了从密实颗粒流到快速颗粒流等不同流态的粒径分聚过程。通过与相应的颗粒流粒径分聚离散元模拟结果进行对比,该模型很好地再现了不同流态的颗粒流粒径分聚过程中,颗粒介质内部的物质输运过程和运动状态演化。更多还原

【Abstract】 Granular materials are pretty common in engineering and nature.Many effective theories are proposed to explain the mechanism of granular flow segregation.However,different theories,such as Fan-Hill-Tan theory and Kinetic theory,are available for different regimes of granular flow.In this paper,a unified segregation model that can cover diff-erent flow regimes is developed based on the mixture theory a numerical scheme for the size segregation of binary mixture granular flow in different flow regimes is proposed with the help of a modified Material Point Method.Based on this numerical model,coupling simulations of granular flow and segregation are achieved,flow features as well as final segregation patterns are simulated pretty well in both rapid and dense slow granular flows.更多还原