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Geometry issue

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I created 3D geometery of greenhosue and imported it into COMSOL interface. But I am not able to assign the internal room space as air domain and then assigne the material property as fluid. I am looking for someone to help me to resolve this problem.



4 Replies Last Post Sep 29, 2023, 2:47 p.m. EDT
Robert Koslover Certified Consultant

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Posted: 11 months ago Jun 2, 2023, 11:53 p.m. EDT
Updated: 11 months ago Jun 3, 2023, 1:34 p.m. EDT

I'm going to guess that the geometry you imported was of the greenhouse structure alone, not the volume of space within it or around it. If so, that's your problem. If you want to model physics in volumes within or around the greenhouse, then you need to create meshable domains for those regions.

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Scientific Applications & Research Associates (SARA) Inc.
www.comsol.com/partners-consultants/certified-consultants/sara
I'm going to guess that the geometry you imported was of the greenhouse structure alone, not the volume of space within it or around it. If so, that's your problem. If you want to model physics in volumes within or around the greenhouse, then you need to create meshable domains for those regions.

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Posted: 7 months ago Sep 29, 2023, 2:35 p.m. EDT
Updated: 7 months ago Sep 29, 2023, 2:34 p.m. EDT

Hi Robert, Thank you for your reply. I will try create geometery lwith meshable domains. In fact, creating geometeries with COMSOL is quite challegning for me. I used to draw in autocad, sketchup etc. When importing, it creates problem. Would you recommend me the best compatible CAD software for COMSOL.

Hi Robert, Thank you for your reply. I will try create geometery lwith meshable domains. In fact, creating geometeries with COMSOL is quite challegning for me. I used to draw in autocad, sketchup etc. When importing, it creates problem. Would you recommend me the best compatible CAD software for COMSOL.

Jeff Hiller COMSOL Employee

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Posted: 7 months ago Sep 29, 2023, 2:40 p.m. EDT
Updated: 7 months ago Sep 29, 2023, 2:40 p.m. EDT

Hello Muhammad,

Since you seem to have successfully imported the greenhouse structure itself, you only need to use Cap Faces to create the air domain inside it. No need to start from scratch.

Search the Discussion Forum for "Cap Faces" for more details on that capability. It has been discussed a few times before.

Jeff

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Jeff Hiller
Hello Muhammad, Since you seem to have successfully imported the greenhouse structure itself, you only need to use Cap Faces to create the air domain inside it. No need to start from scratch. Search the Discussion Forum for "Cap Faces" for more details on that capability. It has been discussed a few times before. Jeff

Robert Koslover Certified Consultant

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Posted: 7 months ago Sep 29, 2023, 2:47 p.m. EDT
Updated: 7 months ago Sep 29, 2023, 2:51 p.m. EDT

Personally, and speaking only for myself, I like to use the Comsol-included drawing tools, along with Comsol's Design Module to help in more complicated situations. I don't have any strong preferences for other CAD or similar software. Now, in the case of your greenhouse, if the Comsol Multiphysics can understand/resolve your imported geometry (even if it is initially just the greenhouse material, and not the space inside or outside it), you could simply create a simple block that is large enough to include the whole greenhouse, and add that to your model. After that, you can either subtract (Boolean difference operation) the greenhouse from the block or simply leave it there, if you wish to mesh/work with the structural details of the greenhouse itself. Regardless, all you'll need to do is specify all the correct physics and boundary conditions, create the mesh, set up the solver appropriately, execute the calculation, perform post-processing, etc. Edit: And... Jeff got this first again. Interesting response, too. I didn't know "cap faces" was that general/powerful, so I intend to take a look at that. Thank you, Jeff!

-------------------
Scientific Applications & Research Associates (SARA) Inc.
www.comsol.com/partners-consultants/certified-consultants/sara
Personally, and speaking only for myself, I like to use the Comsol-included drawing tools, along with Comsol's Design Module to help in more complicated situations. I don't have any strong preferences for other CAD or similar software. Now, in the case of your greenhouse, if the Comsol Multiphysics can understand/resolve your imported geometry (even if it is initially just the greenhouse material, and not the space inside or outside it), you could simply create a simple block that is large enough to include the whole greenhouse, and add that to your model. After that, you can either subtract (Boolean difference operation) the greenhouse from the block or simply leave it there, if you wish to mesh/work with the structural details of the greenhouse itself. Regardless, all you'll need to do is specify all the correct physics and boundary conditions, create the mesh, set up the solver appropriately, execute the calculation, perform post-processing, etc. Edit: And... Jeff got this first again. Interesting response, too. I didn't know "cap faces" was that general/powerful, so I intend to take a look at that. Thank you, Jeff!

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