Convergence Problems in multi-phase buoyant flow
 

Hi all,

I am studying the behavior of an air bubble rising in stagnant water. For this I have defined a rectangular tank as domain with wall as bondary conditions at all its sides (I mean, it is a closed box), and started from a spherical bubble which is located on tank bottom. This simulation is transient but I have convergence problems between time steps, results have not converged after 150 loops. I treated with a openning condition on tank top, with open pressure equal to 0 Pa, but the problem is still going on.

Can you give me a suggestion about what boundary condition is the better way for my problem? and How can I improve converge in multi-phase buoyant flow?

Thanks a lot!

Miguel