The coefficient of restitution (CoR) is an empirical parameter in dense gas-particles computational fluid dynamics (CFD) by means of kinetic theory of granular flow (KTGF). A great sensitivity of CoR on predictions was found because of the existence of multiple collisions of particles in fluidized beds. In present study, an empirical correlation of granular CoR is proposed using a coupled KTGF of Euler granular phase and the discrete element method (DEM) of Lagrange discrete particles. The CoR is calculated using statistical methodology according to relative velocity of two colliding discrete particles. The granular CoR is computed from granular volume fractions, indicating that the multiple collision effects on momentum conservation over collision at high granular volume fractions. The granular constitutive equations for the transport coefficients are solved according to granular CoR. The simulated bed expansions agreed with experimental measurements. The predicted granular pressure and viscosity are compared with measured data.

恢复系数 (CoR) 是稠密气体粒子计算流体动力学 (CFD) 中的一个经验参数，它采用颗粒流动力学理论 (KTGF)。由于流化床中颗粒的多次碰撞的存在，我们发现 CoR 对预测的敏感性很高。在本研究中，使用欧拉颗粒相的耦合 KTGF 和拉格朗日离散颗粒的离散元方法 (DEM) 提出了颗粒 CoR 的经验相关性。根据两个碰撞离散粒子的相对速度，使用统计方法计算 CoR。颗粒 CoR 是根据颗粒体积分数计算的，表明多次碰撞对高颗粒体积分数碰撞时动量守恒的影响。根据粒度 CoR 求解传输系数的粒度本构方程。模拟的床膨胀与实验测量一致。将预测的颗粒压力和粘度与测量数据进行比较。