Dear Niki, I think the problem is the stiffness of mass conservation convergence in internal flow cases. Based on my trials, no matter bdf2, euler, tvd-rk3 or rk4, convergence is facing stiffness. I have attached the convergence history files in this email, which show convergence stiffness.
Since my case files are bit of large, I uploaded in Google drive. https://drive.google.com/drive/folders/1kTfODnbc5JDax0fhrwXJts79W79CdmYI?usp=sharing I added a pressure gradient in the momentum equation as you guided, so the solver will be a little bit different. You have to modify the mako kernel like below so that the case is running correctly. Otherwise there will be no driving source. tdivtconf[${i}] = -rcpdjac*tdivtconf[${i}] + ${ex}; % endfor + tdivtconf[3] = tdivtconf[3] - 4.0; </%pyfr:kernel> The convergence issue only happens when flow is turbulent but not larminar. Best regards, Will -- You received this message because you are subscribed to the Google Groups "PyFR Mailing List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send an email to [email protected]. Visit this group at https://groups.google.com/group/pyfrmailinglist. For more options, visit https://groups.google.com/d/optout.
