CFD simulation of gas-solid-liquid fluidised bed reactor

Abstract

An Eulerian multi-fluid computational fluid dynamics (CFD) model was used to simulate a gas-solid-liquid fluidised bed to analyse the behaviour of fluidised bed with varying inputs on the pressure drop, bed expansion and also gas hold up in the column. Simulated predictions were also plotted against the experimental results which showed they agree with each other. Results plotted for velocity vector of solid particles, i.e., glass beads reveal that the direction of magnitude is upwards in the centre column and near the wall zone there is downward movement due to absence of bubble regime. The velocity vector behaviour of gas and liquid has also been explained. In addition to this, investigations were also carried out to analyse the bed expansion in the column; it shows that bed expansion increases as liquid velocity increases. Gas hold up and pressure drop distribution were also simulated for the three phase fluidised bed; results reveal that pressure drop decreases as air velocity is increased and vice-versa for gas hold up, i.e., gas hold up increases as air velocity is increased.