Creating an "Open inner region"

I found an example similar to my problem, SimScale
But it uses “Open inner region”, apparently, after the migration to the new version of the interface, it was moved to another place. Where to find “Open inner region”?

My project SimScale


You can find all the old geometry operations (and many more!) inside the CAD Edit Mode:

Yes, I saw that, created the inner area, built the Mesh, but I can’t run the simulation. Read a lot on your site, apparently I am missing something.

Did you receive any error message?


Simulation has errors

The simulation contains only inlet boundary conditions, which will most likely lead to global continuity errors. Please select an additional outlet boundary condition.

Your first simulation has only inlet boundary conditions, as stated by the error message:


Please fix this, you should have at least one inlet and one outlet boundary condition. Maybe you meant to use a Pressure outlet?

Also, your model should only contain the flow region, and not the solid parts. Please delete them using the Body - Delete operation in CAD mode.

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Thank you! The tutorial Non-Return Valve Fluid Flow CFD Tutorial | SimScale helped me understand the specifics of the work.
I made a test model, very simplified, and it works fine, but my model is not processed correctly in CAD, there are no gaps and intersections, but something does not work. in Fusoin360 by boolean operations I made an internal air volume model , can I import this model and report the project that it is not a 3D body model, but already an environment model without solids?

Hi pavluchenkor,
I looked around at your projects and I see that the model has not been run again with the inclusion of the pressure outlet, due to an error related to a temporary shortage of simulation availability under the community plan. The simulation is small, with a small mesh and with a shortish run time of 1,000s & hence should be able to be run shortly. The issue occasionally crops up, but you should be able to run the model shortly, but currently there is some Simscale maintenance occurring.

I’m a little confused about the question, but I think…
You can create a 3D model of where the air would flow and now you wish to import this model & tell the Simscale environment, the object created/imported is the fluid region. Short answer, I don’t know, I’m not experienced enough.

Can I suggest that a consistent and similar way that is proven to work is to consider your original design as basically like a pipe with an internal flow and to make use of the pipe flow tutorials is my first suggestion. I also use Fusion 360 and export models to Simscale as a STEP file, but I don’t use the boolean operation for my models. If you wish to address this boolean matter, search for this issue in the documentation & Forum for historical answers over the last 12months.

The other way to think of your model, if you wish to see the internal flow & outflow of air/fluid is to consider the original model as similar to an air conditioning duct where air flows from outside in through the duct into a very large room, Again there are tutorials on air-conditioning, but a little more complex than pipe flows.

Currently some Simscale maintenance is occurring and I can’t provide you with the tutorial/documentation links. So if you can look at the tutorials first on pipe flow, I think this will assist.

An interesting CAD model, so all the best with the future simulation :slight_smile:

Regards Ted

PS: If requesting future assistance and a reference is made to something that worked or didn’t work, leave the success or failure on the dashboard and provide the links as this helps to provide solutions/suggestions.

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