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erschrei July 28, 2009 15:51

"Cannot combine different thread classes"
I received this error trying to grow prism layers in TGRID using "Auto Mesh."

I had selected to not retriangulate, and to "grow individually".

If anyone has seen this error before and has a solution, please let me know!

enilno-dfc April 11, 2013 11:57

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Hi, your question is already quite old, but I thought maybe sb. else is going to have this problem in future also, as I did....
I recieved the same error message as you did, although, I grew the inflations with retriangulation and not individually.
The problem with my geometry was, that I had quite steep angles between face-zones with prism-layers and face-zones without prism-layers.
Though, I recieved prism-layers, along one edge, which have partly been projected to the adjacent face-zone and partly not!
So TGrid built a prism-side, whereever the angle, between inflated face-zone and not inflated face-zone, was too steep to project the prism to the adjacent face-zone.
Apparently this arises a problems within the tet generation.
In the picture you can see:
green -> face-zone without inflations
purple -> face-zone with inflations
light blue -> prism-side
As you can see the prism-side appears at positions where the angle is too steep to project it on the green face zone
The gap between the green face-zone and the purple face-zone is the area, where the prism-layers have been projected properly!
This angle can be changed in the prism settings, in the project tab, by changing the "Max Adjacent Zone Angle".

I know this does not describe or explain exactly your problem, but it gives a good hint, where the error may be!

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