[Sidique]

Hi everyone. I am trying to develop UDF to calculate the bubble velocity for certain number of time steps for 2 phase gas-liquid slug flow in vertical pipe, and then calculate new inlet velocity and check if convergence is established between initial and calculated velocity. If convergence is established then stop solution and hence calculated velocity is the terminal bubble velocity. If not, then reassign new calculated velocity to boundary condition and repeat process until convergence is established. Any suggestions??
I am using Volume of Fluid method (VOF) in Ansys Fluent to simulate two phase slug flow. The problem is that to reach the pseudo-steady solution the Taylor bubble should ceases moving up or down in the axial direction of the bubble and hence the inlet velocity is the terminal velocity and convergence is established. So if that is not reached we need to calculate new velocity (based on bubble movement in solution) and reassign new velocity in boundary condition.