Ansys Structural- Symmetry BC Problem
 

Hi,
I am doing a structural analysis on a very basic geometry, Its a Cylinder(Crucible or Glass like geometry), i am Doing this analysis on Half of the geometry and trying to apply the symmetry conditions to accomodate for the rest of the geometry. The problem is , When i fix(FIXED Support) the Bottom Face (Base of the crucible) i get symmetric results, But when the bottom is "Frictionless Support" the results show that it is not behaving like a Cylinder, it means that the symmetry is not working fine? Can anyone please help in this matter?

Image-1: Symmetry Face.
https://www.dropbox.com/sh/rqbcp32wo...2-Symmetry.PNG

Image-2,3[File: "7-deform","7-stress"] : Results with Bottom Fixed (Show Symmetric Behaviour)
https://www.dropbox.com/sh/rqbcp32wo...eformation.PNG
https://www.dropbox.com/sh/rqbcp32wo...1/7-Stress.PNG

Image-4,5[file name "Deform","Stress"] : Results with Bottom as Frictionless Support(Doesnt seem to be symmetric)
https://www.dropbox.com/sh/rqbcp32wo...Xmn/deform.PNG
https://www.dropbox.com/sh/rqbcp32wo...AaN/stress.PNG

Thanks!

Hello Mudassir,
I understand that you get different results using different boundary constraints.
I think the problem is not the symmetry BC, but the way you applied the constraints on the bottom.
Can you elaborate on the way you applied the loads?

Thanks Florin,

I just got this problem solved, but i am having some other problem now, May be you can help in that too.
I am doing stress analysis as yo can see above, I need GUIDANCE regarding Meshing of this.
What type of mesh should i use? How to assure the mesh quality, and that results are near to what would be actually, Etc Etc.

Can you help?

Thanks again!

Mudassir

Hello Mudassir,
I would use hexa elements; make sure the midside nodes are on; you can switch the on in global mesh settings, advanced.
Make sure you have at least 3 elements on the thickness; to do this you can impose a proper the size of elements on the body.
After the analysis is done, I recommend to do a convergence study, to be sure that you results have converged.