循环床内气固两相流中稠密颗粒间碰撞的数值模拟

NUMERICAL SIMULATION ON INTER-RARICLE COLLISION IN DENSE GAS-SOLID OF CIRCULATING BED

循环床内部的流动属于复杂不均匀的稠密气固两相流，稠密颗粒间的相互作用是影响颗粒运动和浓度分布的不可忽视的重要因素。本文采用直接模拟Monte－Carlo算法（DSMC算法）来模拟颗粒间的相互碰撞过程，并与随机轨道模型结合起来综合考虑湍流和颗粒碰撞对颗粒运动和浓度分布的影响，模拟结果预报了床内分层流动结构和颗粒在稀相区的不均匀分布，计算结果与实验定性符合。

In this paper, based on the similarity between the collision of dense particles in gas- solidflow and that of gas molecules in rarefied gas, inter- particle collision is investigated accordingto Direct Simulate Monte Carlo algorithm. The stochastic trajectory model and DSMCalgorithm are used to take into account the turbulence diffusion and inter-particle collision.Computational results are generally consistent with experimental data. In comparison withthe case in which inter-particle collision is neglected, the computational results indicateinterparticle collision results in nonuniform distribution of particle and formation of cluster.