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Comsol detecting errors at a boundary that doesn't exist?

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Hi all,

I am getting an error when I run a 2d semiconductor/heat transfer in solids model. The warning text (attached screen shot) reads: "Deprecated behavior: Evaluation of the partial expression failed, which forced the full expression to be zero. Partial expression: comp2.semi.Gn Full expression: down(comp2.semi.Gn) Boundary: 75

Deprecated behavior: Evaluation of the partial expression failed, which forced the full expression to be zero. Partial expression: comp2.semi.Gp Full expression: down(comp2.semi.Gp) Boundary: 75"

However, my model only has 70 boundaries, (other screenshot). I'm not quite sure what to do about this, it happens specifically when I add two domains to the "heat source" node, and happens even when I have 0 power applied to the device. In addition, the crash even happens in a study step that doesn't solve for the semiconductor module at all, which is strange considering the error is for a semiconductor module variable (carrier degeneracy).

I'm really stuck at troubleshooting right now, any amount ideas or help would be vastly appreciated.



2 Replies Last Post Jun 24, 2021, 4:28 a.m. EDT

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Posted: 4 years ago Feb 18, 2021, 11:41 a.m. EST

Hi John,

Did you get any answer for this error. I too facing the same issue!

Hi John, Did you get any answer for this error. I too facing the same issue!

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Posted: 3 years ago Jun 24, 2021, 4:28 a.m. EDT

I have similar issue, as well. I simulate one model describing adsorption process in desiccant channel and it works perfectly. However, as soon as I change the shape of the channel (domain geometry) I get the same message, although the model is able to converge, but it doesn't deliver good results. For some of these shapes, I managed to get good results once I've chqnged the mesh. However, for other shapes it still won't work, even though the mesh quality is quite good. Is there anyone who can help us with this issue? Is there some cause other than the meshing that can bring this behavior? Thanks in advance,

I have similar issue, as well. I simulate one model describing adsorption process in desiccant channel and it works perfectly. However, as soon as I change the shape of the channel (domain geometry) I get the same message, although the model is able to converge, but it doesn't deliver good results. For some of these shapes, I managed to get good results once I've chqnged the mesh. However, for other shapes it still won't work, even though the mesh quality is quite good. Is there anyone who can help us with this issue? Is there some cause other than the meshing that can bring this behavior? Thanks in advance,

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