On Thu, Dec 22, 2011 at 7:37 PM, Mohamad M. Nasr-Azadani <mmnasr at gmail.com>wrote:
> Thanks so much Jed for your prompt response. I will start experimenting > with all the suggestions. dtol failure is impossible for GMRES (and CG). Consider checking with that. Matt > Best, > Mohamad > > > On Thu, Dec 22, 2011 at 5:31 PM, Jed Brown <jedbrown at mcs.anl.gov> wrote: > >> On Thu, Dec 22, 2011 at 19:20, Mohamad M. Nasr-Azadani <mmnasr at >> gmail.com>wrote: >> >>> Any hints on what is happening here or how I could narrow it down? >> >> >> I would start by following the general advice in the FAQ >> >> http://www.mcs.anl.gov/petsc/documentation/faq.html#kspdiverged >> >> >>> I know that we had an early discussion on the convergnce for the >>> incompressible CFD problems and boomerAMG preconditioning, >> >> >> That was about solving the coupled system. That shouldn't be an issue for >> the Poisson problem. >> >> >>> but it seems that for this case, that is the only one that does not blow >>> up for most of the time integration I have. >> >> >> Since this problem only occurs after long time integration, you might >> consider writing out the model state when you see divergence so that you >> can experiment with alternative methods quickly. >> > > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20111222/1e7a82da/attachment.htm>
