& If I use Coupled solver I cannot continue simulation more than flow time of 0.5s, but for PISO solver I have no problem to continue for longer time (say 2s). But for PISO case, no wall film is forming on pipe wall after a certain distance. Here I have attached an image of film thickness on pipe wall for Coupled and PISO solver. Is there any particular reason of this difference.? I am using same settings for both cases except solver. After 0.5s I am getting divergence and floating point exception if I use Coupled solver.
Regards Anadi