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Can we impose a MINIMUM STEPSIZE AS A STOP CONDITION?

Posted 30.10.2011, 18:14 GMT-4 Interfacing, Studies & Solvers Version 4.1, Version 4.2, Version 4.3b 4 Replies

Francois Gregoire
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I loop thousands of transient simulations in matlab and I can't find a solver setting that will stop the solver when the step size becomes very small (history of the stepsize in log file) and the simulation becomes a terrible waste of time.

Is there a way to impose a low limit on the stepsize of the solver? I tried various Stop expressions with no success (ex. stepsize-1)...

Anyone knows how to do that?

Thanks,
Frank
4 Replies Last Post 12.11.2013, 23:41 GMT-5
Francois Gregoire
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Posted: 1 decade ago 01.11.2011, 08:07 GMT-4
Nobody uses such a stop condition?

I tried to play with the 'Limit on nonlinear convergence rate' under 'Damping and Termination' in 'Fully Coupled' under my Time-Dependent Solver. But in order to be able to adjust the Limit on nonlinear convergence rate, we have to choose a Constant Damping Method, and my solutions are much better when the Damping Method is set to Automatic (no oscillations, quicker, etc.). So I had to let go this possibility.

Anyone has an idea of a Termination technique when a Time-Dependent Solver progresses endlessly with very small stepsize?
Nobody uses such a stop condition? I tried to play with the 'Limit on nonlinear convergence rate' under 'Damping and Termination' in 'Fully Coupled' under my Time-Dependent Solver. But in order to be able to adjust the Limit on nonlinear convergence rate, we have to choose a Constant Damping Method, and my solutions are much better when the Damping Method is set to Automatic (no oscillations, quicker, etc.). So I had to let go this possibility. Anyone has an idea of a Termination technique when a Time-Dependent Solver progresses endlessly with very small stepsize?
Nagi Elabbasi Facebook Reality Labs
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Posted: 1 decade ago 01.11.2011, 08:21 GMT-4
If you want the solver to stop when the time step becomes smaller than a specific value X, add this expression as a Stop Condition “timestep-X”

Nagi Elabbasi
Veryst Engineering
If you want the solver to stop when the time step becomes smaller than a specific value X, add this expression as a Stop Condition “timestep-X” Nagi Elabbasi Veryst Engineering
Francois Gregoire
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Posted: 1 decade ago 01.11.2011, 16:02 GMT-4
It hurts...

Thank you very much, you made my day Mr Elabbasi.
It hurts... Thank you very much, you made my day Mr Elabbasi.
Marco Zanoni
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Posted: 1 decade ago 12.11.2013, 23:41 GMT-5
Hi,

I have the same problem. Did you find any solution for that?

Thanks.

Marco
Hi, I have the same problem. Did you find any solution for that? Thanks. Marco

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