流化床内超细颗粒的流动

ULTRAFINE PARTICLE AGGREGATION FLOW IN FLUIDIZED BEDS

基于气体分子运动论和颗粒动理学,建立超细颗粒气固两相湍流流动模型,模型考虑了气相与颗粒聚团之间以及颗粒聚团之间的动量和能量的传递和耗散。建立超细颗粒固相粘性系数、超细颗粒压力等物性参数计算模型。超细颗粒的聚团改变了单颗粒碰撞动力学以及颗粒相压力、粘性系数等输运特性。模型模拟计算颗粒聚团直径分布与Zhaolin等[1]实测值相吻合。

A two-fluid flow model of gas-particle aggregations mixture considering the interaction and energy dissipations between gas and particle aggregations was developed based on kinetic theory of dense gases and granular flow. The models of particle viscosity and pressure of gas-aggregations mixture two-phase flow were proposed. The particle aggregations changed the transport characteristics of solid and gas phases. The flow structure of particle aggregations appeared a complex process which related with particle contact bonding energy. The simulation results are agreement with experimental data measured by Zhaolin, Mooson and Hongzhong[1]. More accurate and experimentally verified gas-particle agglomerate flow is needed to refine present model predictions, and more rigorous mathematical integration over the agglomerating domain.