Fundamental Bubbling Characteristics in a Rotating Fluidized Bed: Modeling and Measurement of Bubble Size

Modeling and measurement of bubble size in a rotating fluidized bed (RFB) were conducted. The model for predicting the bubble growth in RFB has been proposed based on the following concepts: (i) local centrifugal acceleration and excess gas velocity are considered as the parameters in the radial direction, and (ii) bubble volume flow locally changes depending on the radial distance. Bubbling behaviors were also experimentally observed by means of a high-sped video camera. Bubble sizes were measured using an image analysis technique, and the measured bubble sizes were compared with the estimated values by our proposed model and the available one for a conventional fluidized bed. The estimated bubble sizes by our proposed model showed good agreement with the measured ones, while the predicted ones by the model for conventional fluidized bed underestimated. The validity of our proposed concepts for modeling of bubble growth in RFB was confirmed.