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Convergence issues with 2D DC discharge in Plasma module
Posted 2020年4月11日 GMT-4 18:43 Electromagnetics, Plasma Physics, Fluid & Heat Version 5.5 2 Replies
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I am trying to model a 2D DC dishcarge in nitrogen with an external circuit.
I tried both by using an external circuit physics and using the COMSOL's inbuilt series RC circuit.
I could not make much headaway witht he inbuit COMSOL circuit but while using an external circuit, I was able to start the simulation running. But I coudl not get the soution to converge.
Most frequent errors I ha gooten previously was "failed to find consistent initial values" which seemed mostly from mesh issues.
The model is attached.
I have tried numerous attempts in fining and coarsing my mesh as well as shortening the time-step. But could not seem to do better.
WIll greatly appreciate if someoen could take a look at this and suggest directions of approach.
-------------------Thanking you,
-Malik M Tahiyat
Graduate Research Assistant,
Department of Mechanical Engineering
University of South Carolina (USC)
300 Main Street, Room A 137
Phone: +1(803)-318-0274
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Malik,
we don't have the plasma module, so can't say anything about the physics settings. But in many cases the time dependent step needs a stationary step before, that provides the initial values. Another option is to ramp up the boundary conditions slowly from 0 to the setpoint.
Cheers Edgar
-------------------Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
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Edgar,
Thank you very much for your reply.
Can you procide instructions how to include the stationary step and how to ramp up the boundary conditions?
That would be very helpful.
-------------------Thanking you,
-Malik M Tahiyat
Graduate Research Assistant,
Department of Mechanical Engineering
University of South Carolina (USC)
300 Main Street, Room A 137
Phone: +1(803)-318-0274