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Parametric sweep solution is lost after non-convergence

Posted 27 nov. 2014, 05:16 UTC−5 Low-Frequency Electromagnetics, Heat Transfer & Phase Change, Studies & Solvers Version 4.4, Version 5.0 1 Reply

Jan
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Hi, I'm running a time-dependent simulation, using electric currents and solid heat transfer physics. I'm ramping up the current with time, which heats the material. I have included an effect, which makes the current increase with temperature. At one point, the temperature and current will have a positive feedback effect, which should increase the temperature to infinity, and thus I get non-convergence at some timestep. This is expected. I need the solution before the non-convergence.

Now, when doing regular simulations (without parametric sweep), the solution is kept, but when doing a parametric sweep (e.g. over a range of geometries), the solutions are not kept when non-convergence occurrs.

Currently I'm doing every simulation without a parametric sweep, find the timestep when it doesn't converge and, create stop-conditions for those timesteps and then run the parametric sweep to get all the data conveniently. This is inconvenient and basically means I have to simulate everything twice.

Any ideas? How to keep the non-converged solutions in parametric sweeps?
1 Reply Last Post 14 janv. 2015, 14:41 UTC−5
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Hello Jan

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Jan
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Posted: 10 years ago 14 janv. 2015, 14:41 UTC−5
For anybody else having similar troubles:

I made a stop condition with the timestep variable so that the solver stops the solution before non-convergence and all the solutions are kept.

e.g. my stop condition (the t>25 is because at the start, my solver was also using small timesteps)

t>25[s]&&timestep<0.0002[s]
For anybody else having similar troubles: I made a stop condition with the timestep variable so that the solver stops the solution before non-convergence and all the solutions are kept. e.g. my stop condition (the t>25 is because at the start, my solver was also using small timesteps) t>25[s]&×tep

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