摘要
颗粒碰撞是快速颗粒流的动量传递,能量传递及耗散的主要机制。因此,碰撞应力是快速颗粒流研究的主要内容。本文基于大小均匀、光滑圆球颗粒的非弹性碰撞模型,类比气体分子动理论中的处理方法得出快速颗粒流积分形式的碰撞应力,能量传递通量及能量耗散率等关系。在颗粒速度分布函数的一级近似式符合Maxwell分布的假设下,对碰撞应力积分得出相应于Boltzmann方程二级近似解的碰撞应力表达式。在简单快速颗粒流动条件下,本文的理论结果与实验资料符合较好。
Particle collisions are the main mechanism of the momentum transfer, the energy transfer and the energy dissipation for rapid granular flows. Therefore, attention is paid to the collisional stresses in the study of rapid granular flows. Based on an inelastic collisional model of uniform, smooth and spheric particles, the collisional stress tensor, the collisional energy flux and the rate of energy dissipation, which are expressed in integral forms, are all obtained in this paper by analogizing the method in the kinetic theory of gases. If the Maxwell distribution is supposed as the first order approximation of the particle velocity distribution function, the collisional stress tensor may be integrated and the corresponding second order approximation solution of the Boitzmann equation is thus obtained subsequently. The comparisons show that the present theoretical results and the experimental data for the simple shear rapid granular flows agree very well.
出处
《力学学报》
EI
CSCD
北大核心
1993年第3期348-355,共8页
Chinese Journal of Theoretical and Applied Mechanics
关键词
颗粒流
动理模型
碰撞应力
rapid granular flow, kinetic model, collisional stresses, dispersive stresses
