Pressure fluctuations in a gas-solids fluidized bed — effect of external noise and bubble residence time distribution

Abstract

A dynamic model has been proposed to describe the dependency of the dominant frequency on the various physical parameters of a gas-solids fluidized bed. It has been shown that the proposed model can predict not only the dominant frequency of bed fluctuations, but also the pressure signals at the plenum or even at an arbitrary bed position. The power spectrum, auto-correlation coefficient and probability density of the fluctuating signal have been obtained by solving the linearized dynamic equations of the model. To test its validity, the proposed model has been conpared with the available experimental data. The result indicates that the proposed model can, at least semi-quantitatively, describe the experimentally observed pressure signals.