merging meshes step 18

[Stephanie Rocha]

Hello everyone, 

I am a masters student currently using deal.ii for the first time 

I am trying to modify the shape of step 18 into a top and bottom cubes (who were supposed to be cylinders but that's a different story) with three cylinder shells in between. My issue is that the geometry does not seem to merge together. I am not sure if this is a node issue or if there is a certain way to connect each shape face to face. It seems to only distribute the stress to the top part and not throughout the entire geometry I created. 

I attached the code and a picture to better visualize my predicament. 

Thanks to anyone willing to take a look. 

-Stephanie Rocha  

[Sebastian Stark]

Stephanie,

To me it seems that your meshes of the cubes and the cylinders are completely unrelated. However the merge_triangulations() function will only merge coincident nodes of the respective meshes. So, in your case no nodes will be merged. If you want to make your example work with non-coincident meshes, you will have to implement constraints tying the relevant dofs together manually (which is quite awkward). But for your example I think it's more reasonable to make sure that the relevant nodes of your parts coincide. If it was just one cylinder shell (or 4 of them) I would say you can make up something combining GridGenerator::cylinder(), GridGenerator::cylinder_shell() and GridGenerator::hyper_cube_with_cylindrical_hole(). But as there are three cylinder shells it's probably easiest to use an external grid generator like gmsh to mesh the whole thing at once and import the mesh afterwards. As a starting point I guess tutorial step 49 might be very helpful for you: https://www.dealii.org/current/doxygen/deal.II/step_49.html

I hope that gives you an idea.

Regards, Sebastian

[Stephanie Rocha]

Thanks Sebastian! 

I will look into it :) 

--
The deal.II project is located at http://www.dealii.org/
For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en
---
You received this message because you are subscribed to the Google Groups "deal.II User Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to dealii+un...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/f0216c17-7b0b-4e60-b0a0-de33d31522ba%40googlegroups.com.

--

Respectfully, 

-Stephanie Rocha 

Student and class representative of MSS19 at ISU - International Space University. Strasbourg, FR

Mechanical Engineer - University of New Mexico, USA