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Monitoring a long (time-dependent) simulation & "Plot while solving" feature

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I'm having trouble finding a way to monitor a long simulation while solving; I hope someone here has some tips.

Background: (Using COMSOL 4.2)
I'm modeling an EDLC (Physics involved are Electrostatics, Transport of Diluted Species, Heat Transfer). I've successfully simulated a single charge-discharge cycle, but I need to run multiple cycles. I've had trouble in the past with one of my variables (temperature) behaving as expected for a while and then veering off into behavior that is not physically possible/plausible within the model setup. This only happens occasionally and does not occur at consistent times during the simulation, so I think it is a numerical issue rather than a mistake in the model setup.

This behavior happens occasionally when the simulation is simply started and allowed to run its course. The likelihood increases if I stop the simulation to check the results up to that point and then try to continue the simulation from that point. Stopping one solver after a single cycle and trying to use this as the initial conditions for the next simulation has been even more problematic. Monitoring the convergence plots is not enough to catch this; they often look quite close to those of a successful run.

Current problem:
This time, I tried plotting the temperature at one point while solving, so I could monitor it without stopping the simulation. However, the progress of the simulation seems to have been slowing down the longer the simulation runs. I assume this is because it has to plot an increasing amount of data after each output time.

1. Is there a way to stop the "plot while solving" function without stopping and restarting the simulation?
2. Are there any settings I could play with to reduce the impact of "plot while solving" on the solution time?
3. Is there any other way to check the data for this variable while the solver is running, without using "plot while solving"?

Any advice will be much appreciated! Thanks!

1 Reply Last Post Mar 27, 2012, 5:31 p.m. EDT

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Posted: 1 decade ago Mar 27, 2012, 5:31 p.m. EDT
3. In Time-dependent solver, you can add "Stop Condition"
3. In Time-dependent solver, you can add "Stop Condition"

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