Solved: Analysis has stopped because the Solver has exited Unexpectedly

Anonymous · ‎10-04-2016

I have a model that is producing the "Analysis has stopped because the Solver has exited Unexpectedly" error. The MaxRadMatrixSize has already been increased to 10,000. Cannot figure out why this is happening on this particular model. Model includes volume flow rate inlet, centrifugal fan, pressure drops, fans, heat generation and pressure = 0 outlet. The simulation looked like it was going fine and coming toward a converged solution when suddenly the TKE shot up and it stopped.

CFZ file attached.

Jon.Wilde · ‎10-04-2016

Your centrifugal fan and flow boundary conditions are doubling up on each other, I suggest you only need the fans.

The fans need to have a smaller sized disc on one face as the inlet/outlet, check out the article here: Centrifugal Fan.

Fans and Resistances both need good uniform meshes with 4-5 elements through their thickness.

Otherwise, this looks pretty well set up to me!

Hope that is useful,

Jon

Jon Wilde
Technical Support Manager

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Anonymous · ‎10-04-2016

Hi Jon,

I knew it would be something to do with the centrifugal fan! This is the first simulation I've tried with this material, so I was doubtful it would work first time! I've done those items you mentioned and the simulation and it all looks good and stable thus far. I guess the inlet having shared cells with the outlet was likely causing the issue.

Many Thanks,

Matthew Gent

Anonymous · ‎10-07-2016

Hi Jon,

Some good news and some bad news. The good news is that the simulation mentioned in this post earlier worked fine and with a good result 😄 however, the bad news is that today I cloned the scenario and made the mesh finer in order to achieve a more accurate solution and the simulation failed again with the same "The analysis has stopped because the Solver has exited Unexpectedly" message 😞 Since the only thing that changed is the mesh I'm once again a little confused. It was attempted on the CLOUD, with an approximate element count of 4.2M. Could the autodesk hardware have run out of resources in this instance?

Regards,

Matthew Gent