Problems with. Thermal Management Tutorial: CHT Analysis of an Electronics Box

Hello, I am trying to follow the " Thermal Management Tutorial: CHT Analysis of an Electronics Box" tutorial and there are a few steps which the options on the simscale differ from those on the tutorial but i believe that I was able to make sense of all of them apart from the fan graph inputs. the “Q” option in the tutorial does not seem to be any option in the current simscale so I set the pressure as static 250pa

Never the less, 30 minutes after the simulation began I encountered this.

“Job was prepared successfully.
Run pre-processing finished.
Temperature field started diverging. Please check the mesh quality near the reported location and try refining the mesh. If the problem occured near a boundary, please check the boundary conditions. In case of doubt, please ask for assistance via our support chat. Temperature = -101443 at position: (0.02681 m, -0.002137 m, 0.02196 m).”

I assume other people have had luck with this tutorial? where can you find positional information? Is there a decent tutorial on regional meshing?


I presume you are talking about the outlet boundary condition being different from the one used in the tutorial? By defining 250 Pa absolute pressure to the outlet, you will definitely run into issues. This is almost a perfect vacuum.

In any case, please refer to pointer number 2 under Figure 28 in the tutorial:

The boundary condition needs to be a “Custom” boundary condition instead of “Pressure outlet”. Once you have a custom boundary condition, you will see the same set up options as seen in the tutorial.


hey thanks for the input.

Perhaps my issue is that I don’t have a “fan outlet” option. Or perhaps I am missing something else. thoughts?


It should be available, but as I mentioned, it requires a custom boundary condition, instead of pressure outlet:



Hey thanks! i was blind.

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