Abstract
A semicylindrical fluidized bed of 15 cm diameter with a transparent flat wall was employed to observe bubbles visually. The bed was operated in a range of (UG-Umf) from 8 to 35cm/s, showing the bubbling and slugging regimes. No effect of particle size on bubble size was observed for different sands of 75 to 521 μm in average diameter, where the different sands were compared at the same (UG-Umf) value. The expressions for bubble growth in bubbling three-dimensional beds by Darton et al. and by Mori and Wen were found to be applicable to the semi-cylindrical fluidized bed operating in these regimes. The absolute bubble rise velocity under the present conditions was found to be well represented by the expression of Allahwala et al. developed for three-dimensional beds.