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yaelgo
Aug12-09, 05:27 AM
Hello,
I'm a 2nd year student, and I'm trying to get to know COMSOL. I'm starting off by solving simple problems with the incompressible Navier-Stokes model, but I keep having trouble with the convegence of the solution.
I keep getting the following error:

"Failed to find a solution:
The relative error is greater than the relative tolerance.
Returned solution has not converged."

I've tried to solve many problems, but it gives me the same error over and over again.
I've changed the number of iterations, the tolerance and the DOF by remeshing, but nothing seems to help.


If someone here has a usefull advice, I would really appreciate it.

Thanks,
Yael.

ariaad
Aug26-09, 06:12 AM
I had the same problem. Comsol has a problem with pressure calculations in Navier-Stokes physics. You have to uncheck "p" on "Solve for" card in Solver Parameters.

yaelgo
Aug26-09, 06:57 AM
Thank you!
but I don't really understand what you mean - I can't see "solve for" in the solver parameters.
could you be more specific? what solver are you using?

Thanks,
Yael.

ariaad
Aug26-09, 06:59 AM
Sorry, my fault - it's in Solver Manager.

yaelgo
Aug26-09, 08:29 AM
it works! thanks :)