Hello all;
I have been working with rings that have a uniform inward radial force applied. The inward force causes the ring to go into compression, which introduces a flexural-torsional buckling mode. This mode results in large axial displacements; the 1st mode can be visualized as the perimiter of a pringles chip. The generic version of the case I am trying to solve is illustrated on the left, with the pink arrows representing the distributed radial load, and the orange arrows representing the resulting compression forces internal to the ring. A model of the typical experimental result is on the right, with the characteristic 4-node "potato chip" shape shown in light blue, and the initial undeformed shape in transparent gray.
Has anyone had experience modeling a buckling scenario such as this? I know the non-linear buckling solver in Solidworks can accurately capture the behavior of linear beams, but haven't yet found any forum posts or other information on ring buckling. I need a way to predict how stiff the ring needs to be in order to prevent the buckling. I have found sytems of analytical equations for this, but in addition to being atrocious, they make too many assumptions that don't apply to our geometry. I would just try the FEA, but I currently only have access to the basic solver, and would love to know if the more advanced one can handle this before I pursue this further.
Any help or tips will be much appreciated. Thanks!
Why wouldn't you do this like any other buckling analysis? Just apply a unit radial load to a free-free model and your first buckling mode should give the load necessary to elastically buckle the ring. Then check stresses to see if you are near yield in which case you will have to do non-linear run.
When modeling something like this for buckling, symmetry is not always your friend as it can sometimes hide some modes.