Abstract:

Through the combination of deceleration method and video observation, the variation law of gas-solid flow with rolling process, the variation characteristics of bed pressure drop and initial fluidization velocity in gas-solid rolling fluidized bed were studied, and compared with those of static vertical bed and inclined bed. The influence of swing on initial fluidization was analyzed, and the prediction model of initial fluidization velocity of rolling fluidized bed was established. The results showed that when the rolling bed was reduced to less than the initial fluidization velocity, and the bed surface was almost perpendicular to the wall surface and no longer tilts with the swing of the bed. The initial fluidization velocity decreased with the increase of rolling amplitude or the decrease of rolling period. Under the same initial loading height, the order of initial fluidization velocity was: vertical bed > inclined bed > rolling bed. The prediction model of the initial fluidization velocity of the rolling bed was established by force analysis, and the fitting degree was good.

Key words: fluidization, rolling fluidized bed, initial fluidization velocity, fluidization curve, bed pressure drop, prediction model

摘要：

通过降速法与视频观测相结合的方式，本文对气固摆动流化床内气固流动随摆动过程的变化规律、床层压降和起始流化速度的变化特性等进行了研究，并与静止直立床、倾斜床进行了对比，分析了摆动对起始流化的影响，建立了摆动流化床起始流化速度预测模型。结果表明：摆动床降速至小于起始流化速度时，床面几乎垂直于壁面，不再随床体摆动而产生倾斜；起始流化速度随着摆动幅度增大或摆动周期减小而减小，在初始装料高度相同的情况下，起始流化速度从大到小依次为直立床>倾斜床>摆动床；通过受力分析建立了摆动床起始流化速度预测模型，其拟合程度良好。

关键词: 流态化, 摆动流化床, 起始流化速度, 流化曲线, 床层压降, 预测模型