Eulerian simulation of a bubble column up to high gas fractions

This study investigates homogeneous flow in a bubble column up to a 50% gas holdup. For low to medium gas holdup the good performance of an established baseline model is confirmed. In this range, the mixture pressure gradient is decisive in determining the relative velocity, resulting in good predictions without considering the swarm effect. However, beyond a gas holdup of ~20%, a swarm corrector becomes necessary, for which several proposals from the literature are evaluated. In addition, the lift force influences the gas fraction profile depending on the bubble size. The resulting profile shape has a significant impact on the liquid flow inside the column. If the profile is wall-peaked, the liquid flow remains moderate, while a center-peaked profile strongly boosts the liquid velocity.