asymmetrical results?

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All questions to: meshing, materials, boundary conditions and element properties

Moderatoren: ccad, mz15, auroraIco, Lehrstuhl

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wohenke
Newbie
Beiträge: 6
Registriert: Di 14. Aug 2012, 10:30

asymmetrical results?

Beitrag von wohenke »

Hi Aurora team,

I noticed (sometimes) that when I have a geometrically symmetrical structure, with forces symmetrically applied to that structure and symmetrical boundary conditions, strain or deformation results are sometimes asymmetrical with respect to the initial situation. This is cannot be physical, since all initial conditions are entirely symmetrical.

To give a trivial example: assume a thin circular disk lying in the x,y-plane with its center located at the origin. Two forces applied are pointing to the center (=origin) along the x-axis on opposite sides of the disk. The disk is fully supported in the z-direction by applying z=0 displacement boundary conditions. Strain or deformation patterns should then be symmetrical to the y-axis,...but sometimesit isn't.

I was wondering whether this effect is caused by inappropriate SORCG solver parameters ( I played around with residuum, which sometimes helped) or insufficient meshing.

Is that known to you and would you have any recommendation to avoid this?

Kind regards
FRudolph
Alumni
Beiträge: 25
Registriert: Mo 22. Okt 2012, 13:12

Re: asymmetrical results?

Beitrag von FRudolph »

Hello wohenke,

you already answered your request by yourself. An asymmetrical mesh delivers sometimes asymmetrical results. As you have in mind the following three recommendations avoid those results:
- use mapped mesh
- refine the mesh
- set the residuum to a lower level

When it still does not work let me know.

With kind regards

FRudolph
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