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Convergence error using batch command line
Posted Mar 15, 2013, 8:46 a.m. EDT Computational Fluid Dynamics (CFD) Version 4.3a 0 Replies
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I want to solve a single phase fluid flow, turbulent low Reynolds k-epsilon model in batch mode. This works fine when trying to run from the COMSOL desktop (i.e. with GUI). However when I try to enter batch mode using command prompt I get a convergence error. I use the following command:
comsol batch -inputfile TurbulentPipeFlow_k-e-lowRe.mph -study std1 -batchlog batchlog.log
The error part of the log:
-----------------------------------------------------------------------------------------------------------
Segregated solver iteration 5.
Substep 1, for group 1.
Current Progress: 5 %
Memory: 899/900 2411/2411
Iter Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.5000000 0.46 5 5 5 43 0.00083 0.14
Substep 2, for group 2.
Scales for dependent variables:
mod1.k: 0.9
mod1.ep: 95
Iter Damping Stepsize #Res #Jac #Sol LinIt LinErr LinRes
1 0.3000000 0.62 17 17 17 220 0.00098 9.7e-05
2 0.3000000 0.52 18 18 18 238 0.00061 0.00012
3 0.3000000 0.41 19 19 19 269 0.00089 0.001
4 0.3000000 0.32 20 20 20 469 0.044 0.94
Stationary Solver 2 in Solver 1: Solution time: 50 s.
The_following_feature_has_encountered_a_problem
Exception:
com.comsol.util.exceptions.FlException: Failed to find a solution
(rethrown as com.comsol.util.exceptions.FlException)
Messages:
The following feature has encountered a problem
Failed to find a solution
In segregated group X#2
Divergence of the linear iterations
Returned solution is not converged
- Feature: Stationary Solver 2 (sol1/s2)
- Error: Failed to find a solution.
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Doing multiple tries, the error always occurs at the same time and the logs are identical. The other turbulence models (k-eps and k-omega) work just fine.
The only reason for this that I can think of is that the comsol batch command starts the batch run with other convergence criteria than a 'normal' run from the COMSOL GUI, but that seems very odd to me. All help is appreciated.
Thanks in advance,
Thomas van der Meer
Attachments:
Hello Thomas van der Meer
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