SimScale CAE Forum

Flow volume extraction error


I am new in Simscale, I don’t know much about it. I am trying to create an internal flow volume using the closed inner region flow volume extraction for the airflow analysis inside a bus that i am currently working on. My CAD model was created with Autodesk Inventor 2017. I am getting an error saying “A closed region could not be created. Please make sure to cover all openings with boundary faces” when i try to create a flow volume extraction as shown in the attached image.

Please assist/advise on how i can resolve this.

Here in the link to my project:

Thank you.

Hey @thorong!

Have you checked this doc entry before: ? :slight_smile:

I will have a look at this later on - tagging the @CFD-SQUAD here as well.



Hi @jousefm

Yes I had went through it before.

Hi @thorong i believe you are selecting the wrong face. For closed inner region you need to select a seed / Assignment face inside the bus.

Hey @thorong,

Welcome! :slightly_smiling_face:

I created an enclosure around the trailer. Notice that the fluid volume isn’t restricted to the outside, which indicates the trailer isn’t completely closed.

I couldn’t find the gaps. That way, I chose to delete all windows and doors. So, instead of using the closed inner region, I used the open inner region. You can see the results below:

You can access the project link here.




Awesome Paulo!!! :clap:

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Thank you so much @paulosantos :clap: !

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Awesome indeed! :clap:

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Thank you!!

Thanks thorong! If you have any other questions, feel free to ask.

Hi @paulosantos

Could you please share with me the edited version of the CAD Model that you did without windows and doors? If possible, please make it in a step (.stp) or part (.ipt) format so that i can be able to open it in Autodesk Inventor? I tried downloading the .x_t one on the project but i am not able to open it in Inventor (it gives me an error).

I need it for another simulation where i will assemble it with other parts.

Thank you.

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Hey thorong! Sure. Here is the link.