Linear Buckling and Symmetry

[Fefe85]

Hello,

I'm working on the buckle analysis of a piece of sheet metal withstanding an axial load. The part is symmetrical to a plane but the geometry is pretty simple and computational power is not a problem so I started modeling the whole with shell elements. Then I tried to model only the half to get symmetrical and antisymmetrical modes (2 separate analysis with different BCs), and got very different results from the original. Which ones should I consider to be reliable ?

Thanks

 

[KyleSong]

Yes, if you find you got different results when you use full model and half model under the same circumstance, I think we are in the same trouble, I am also sincerely ask for help from someone who know the trick of this.

I got a similar problem, for a simple bar under compression, and since the bar is just a straight one, and I just simplify the model as half length and set symmetry boundary condition at one end to make it only half of the whole body, and got a result, then, I found it is not time consuming, so I change it to full length, but the result is so disappointed, even cannot give me a reasonable deformation contour, and all the thing is just the same.

So, please help us, all friends in this forum, your response is highly important for us!

Best Regards,
Kyle

 

[TGS4]

Unless your bucking mode is similarly symmetric, symmetry is strongly discouraged in a bucking analysis.