Abstract: The interaction between gas and particles under different flow regimes, ranging from minimum fluidization to pneumatic transportation, was investigated in a vertical gas-solid flow system. It is found that the drag coefficients could be used to account for the energy exchange in the two-phase flow system. Two diagrams of the drag coefficient at different operating conditions are also obtained. The results of this work show that the heterogeneity of the gas-solid flow (e. g., the bubbling and particle clustering phenomena)could be considered as. the results of an optimal arrangement in which the interaction between gas and particles approaches minimum.

摘要： 本文对垂直气固两相流动系统中,从初始流态化到气力输送的整个区域内气固两相之间的相互作用规律进行了研究.结果表明,采用气体与颗粒群之间的曳力系数可以定量表征两者之间的能量交换过程.文章并讨论了不同操作条件下气固曳力系数的变化规律,并由此可见两相流系统中出现的不均匀状态(低气速时产生气泡,高气速时颗粒趋于聚集)均可用体系为使气流对颗粒群做功最小而采取的运动形态来解释.