An evaluation of the entrance requirements at Radford College

Abstract

The heat transfer coefficient between a horizontal tube and a shallow fluidized bed of alumina particles (335-1261 micron) was measured, and the effects of the tube elevation (10-40 mm), static bed height (10-40 mm), and the design of the distributor were investigated. The cloud zone effect i.e. a sudden increase of the heat transfer coefficient when the tube was located right above the static bed height, has been verified as a feature of shallow bed systems; furthermore, the jet region has shown a dominant effect on the behavior of the shallow bed heat transfer. The results showed that the heat transfer coefficient increased monotonically with increasing air velocity when the tube was located in the jet region, and the heat transfer coefficient increased when a distributor which induced a deeper jet penetration was used. However, the erosion problem and the relatively high pressure drop across the distributor still need to be solved in further studies, so that the greatest economic value of a shallow bed can be achieved.