Importing a solid geometry for a momentum source and mesh generation

Hello, I am trying to model a momentum source for a ventilation fan into a room with underfloor heating. I have tried creating the geometry in sketchup (STL) and now with Onshape (3dm as the online import is not working).
In order to apply a momentum source in Simscale I need to import a solid region in my model. However these seem to get imported as surfaces. Please could someone look at my region named ‘Part 2’ and confirm it is correct for a momentum source.

I have attempted to mesh the model and get the warning
‘The physics can not be taken into account as the simulation setup is not valid. Complete your simulation setup before generating the mesh in order to optimize the mesh for your application.’
I have tried to keep the inputs as simple as possible. Could someone tell me what is missing? I have a green tick for all of the properties.

Model link SimScale Login


I can see that your parts are correctly recognized as solids.

For the momentum source to work, the solid used to define it must intersect with the flow region. In other words, the flow region must also cover the momentum source.

You can find more details in this page:

Please implement this fix and report back, check as there might be other errors, for example the inlet face and walls overlapping with the momentum source.


Thank you. In Onshape I placed a sketch inside the room volume and made an extrusion. This became a separate part and Simscale recognised it as a solid. This works as a momentum source in the simulation and the setup was valid.

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