SimScale CAE Forum

Simulation Error

Hello. My simulation kept saying that “31 regions are being used in a single regiona analysis. Make sure all except for one has Advanced concept assigned.” The sample workbench has 8 regions but it didn’t hinder the simulation.

Please check my workbench and see what’s wrong. Thank you…

You have to make it from the begin, pls following tutorials, it works.

I can see you have a successful simulation run, are you still facing problems?

Yes. I wasn’t able to select bodies for my momentum and passive scalar forces. Can’t select specific bodies. Car and jet fan models were converted into FACES after I created my “flow region”.

I think my problem starts with the model I have imported. It’s a SOLIDWORKS assembly converted to a STEP file. Initially, I had 31 solid bodies in my assembly. Everything’s supposed to have an “Advanced Concept” assignment. But then, I got simulation errors because of these 13 regions the program has detected. No idea what these 13 regions are.

Please help evaluate what’s wrong with my model.

I know. I just can’t established the appropriate model for this. Sample project/workbench has 8 solids, but the simulation went smoothly. Mine has 31 bodies and 13 regions were detected upon simulation.

If you need the parts to be maintained after flow volume extraction, you should select ‘Keep existing parts’:


I would rather suggest you to use the CAD Edit Mode, where you can have a more granular control over the operations and what parts are kept/deleted. Check out for reference:

Thanks but I already tried it… Today, I have run a complete 3 simulations without introducing any car models for passive scalar source. :slightly_frowning_face:

I used the “flow region” as the passive scalar source instead. I would appreciate it if you could check my simulation runs and see if I did everything right. Here’s the link:

See snippets of the simulations I made.

Well, I couldn’t tell if you did everything right, as I am not aware of what you are modeling and the assumptions. From what I can see, the setup looks ok and it runs without failing. It is your job then to analyse results and check if it is realistic.

Thank you for bearing with me up to this point. :wave:

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You are welcome!

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