THE MEASUREMENT OF VOIDAGE OF NONUNIFORMLY FLUIDIZED-BED BY MEANS OF THE WALL-PRESSURE SIGNAL

By the wall pressure signal, DELTAp(x), from a nonuniformly fluidized bed is here termed the excess pressure at a wall Of open column over t he atmospheric pressure measured at a distance x from distributor. The relation was investigated between the wall pressure signal, DELTAp(x) and some specifically defined voidages of a so-called standard bubbli ng bed characterized by the fact that the ratio of the experimentally determined pressure drop for minimum fluidization, DELTAp0,mf, and of the theoretical pressure drop, DELTAp(t), is approximately equal to un ity. We have shown that under certain conditions, the time-volume aver aged voidage, epsilonBAR, of this bed can be determined in terms of si mple relation (13).