For safe and steady operation and prevention of vibration of a fluidized bed, it is
very important to obtain accurate information of fluidization. Hiby [1], Lirag and
Littman [2] and Fan et al. [3] measured the pressure fluctuations and investigated
their relation to bubble behavior. Moritomi et al. [4] measured pressure fluctuation
both in the bed and in the plenum chamber, and derived an empirical equation for
predicting the angular frequency of the spontaneous oscillation of a fluidized bed.
Furthermore, the pressure fluctuations measured in the freeboard and the plenum
were also analyzed in order to diagnose the fluidization state by Tagashira et al. [5]