矩形错流移动床床内颗粒流速分布的考察

THE INVESTIGATION OF PARTICLE FLOW IN RECTANGULAR CROSS┐ FLOW MOVING BED

以矩形错流移动床床内颗粒流动为考察对象，在前人工作的基础上，明确了体积膨胀应力参数 ｋ的物理意义，完善了床内颗粒应力分布的理论预测；并提出了颗粒间发生剪切滑移的理论判据，由此可对不同过床气速条件下床内颗粒流速分布区域的分界点作出理论预测。同时选择了与热态实验物料堆比重相近的小米和硅胶珠为冷态实验物料，在矩形错流移动床中实验考察了床内颗粒流速分布随过床气速的变化规律，结果表明，理论预测与实验相符较好。

In this paper, based on the particle m echanics theory, the differentialequa tions on the particle stress in a rectangular cross flow m oving bed w ere established and thephysicalm eanings of the param eter w as also specified. Then the particle stress in the bedw as calculated and analyzed. Thus by establishing a theoretical criteria on the points ofparticle relative sliding in the bed, the theoreticalanalysis on the particle velocity distribu tion could be predicted. Meanw hile, the particle flow pattern of tw o types of particles inrectangular cross flow m oving bed w as investigated. Itw as found that theoreticalanalysiscould agrees w ellw ith the experim entalresults. Thus the m ethod to predict the particlevelocity distribution w as given based on the experim ental investigation and theoreticalanalysis.