nThank you . It's just that it takes too much time even with a mesh that's this fine. Takes me around 2 days and one night to simulate around 3 seconds worth of simulation time. Any tips on how to reduce this time?nI tried using NITA (Non-iterative Time Advancement) but with the Higher-Order Term Relaxation off I find that it is less stable. I just started with it so I think I am not very good at setting the parameters.nAnother thing is diverging residuals (as shown in the residual picture in this thread), I am not sure what I can do converge them?nI tried decreasing the Under Relaxation Factor but as I find it it just scales down the divergence of the residual but the residuals continue to diverge.nThanks for your time. n