摘要
为了解决颗粒分离的解释机制众多、尚未完全统一的问题,进一步揭示剪切分离更深刻的机制,采用开源软件LIGGGHTS构建三维离散元剪切模型,分析大颗粒周围的空间排列结构,探讨摩擦力、壁面、尺寸差异、惯性等因素对空间结构变化的影响。结果表明:大颗粒能够向上爬升是在2种机制共同作用下进行的;小颗粒群在竖直方向存在速度梯度,层与层的动量传递发生损耗;大颗粒的尺寸效应体现在对前上方小颗粒动量传递模式的改变,由此产生空隙;大颗粒前期靠挤压上升,空隙的产生是大颗粒上升的充分条件;大颗粒后期在后传递颗粒的旋转传动下,沿着小颗粒表面上升。
To solve the problem of many explanation mechanisms for particle segregation being not completely unified,and further reveal deeper mechanisms of shear segregation,a three-dimensional discrete element shear model was constructed by using open source software LIGGGHTS to analysis spatial arrangement structure around a large particle.Influence of factors such as friction,surface,size difference,and inertia on spatial structure change was discussed.The results show that the large particle can upward climb under the combined action of two mechanisms.There is a velocity gradient in vertical direction of small particle swarm,and the momentum transfer between layers is lost.The size effect of the large particle is reflected in the change of momentum transfer mode of small particles in front and above,resulting in voids.The large particle is uplifted by extrusion in the early stage,and the generation of voids is a sufficient condition for the large particle to lift.The large particle rises along the surface of the small particle in the later stage under the rotary drive of the rear transfer particle.
作者
黄仕昭
郑麟
李玉秀
陈颖
HUANG Shizhao;ZHENG Lin;LI Yuxiu;CHEN Ying(School of Materials and Energy,Guangdong University of Technology,Guangzhou 510006,Guangdong,China;College of Energy Engineering,Zhejiang University,Hangzhou 310013,Zhejiang,China)
出处
《济南大学学报（自然科学版）》
CAS
北大核心
2023年第1期94-101,共8页
Journal of University of Jinan(Science and Technology)
基金
国家自然科学基金项目(51776043)。
关键词
致密颗粒流
颗粒分离
离散元法
剪切力
dense particle flow
particle segregation
discrete element method
shear force
