混入粗颗粒对移动床中空腔的抑制效应

摘要

采用离散元方法(DEM)研究了粗颗粒的混入对移动床中空腔的抑制效应.结果表明,向移动床中混入粗颗粒能够抑制空腔的形成,尤其是在粗颗粒的壁面摩擦系数较小的情况下.为了进一步强化混入的粗颗粒对空腔的抑制效应,在粗颗粒与细颗粒的壁面摩擦系数相同时,应将粗颗粒分散在床层中,而对于粗颗粒壁面摩擦系数远小于细颗粒壁面摩擦系数的情况,应将其集中在壁面附近.%Inhibiting cavity formation by mixing coarse particles into a moving bed was investigated by the discrete element method. The results indicated that coarse particles contributed to inhibiting the cavity formation in a moving bed, especially when the wall friction coefficients of coarse particles were lower than those of fine particles. To enhance the effect of coarse particles on cavity formation in the moving bed, the coarse particles should be dispersed in the bed when the wall friction coefficients of coarse particles were the same as those of fine particles, but should be concentrated at wall when the wall friction coefficients of coarse particles were significantly smaller than those of fine particles.