Hello,
I’m trying to simulate buckling of a thin walled cylinder under external pressure. My model is a 36” OD open ended cylinder that is 5” long. I want to simulate the buckling caused by a pressure applied to the entire outside surface. I’m having trouble applying a fixture to the cylinder that doesn’t impact the buckling simulation. Can recommend or explain how to use a fixture that doesn’t impact the loading or end conditions?
Thank you
I am trying to predict the buckling behavior for structural reasons. I would like to compare the Solidwoks results to my critial buckling calculations, and show that the working pressure applied will not cause the cylider will not buckle.
Cut your model down to a wedge shape like this:
Use symmetrical constraints on the two open faces and fix a vertex. The results at the fixed vertex will be false but the other end will be correct.
you have to be careful with assuming symmetry with buckling
This applies for static analysis. The buckling analysis in SolidWorks Simulations is for linear objects. Columns and beams in compression, not pressure vessels.
You need to be very careful with critical buckling values from linear buckling analyses; they're inherently non-conservative. Depending on how much weight you're going to place behind the critical load calculated from your FEM, it might be better to do a 2D axi-symmetric model with non-linear material properties and large displacement-strain formulation.
what fixture are you trying to use?
how is it restrained "in the real world"?
are you trying to do linear buckling or nonlinear buckling?
and like scott asks, what is the goal of the analysis?
I have tried a variety of fixtures mostly working with fixed geometry, roller/slider, and elastic support. I have been working with linear buckling. The real model is essentially a steel clamp of equal width tightening on the 36” OD plastic cylinder. I have tried to analyze this with and without a steel clamp, and have been having issues with fixtures on both.
what is the real world restraint?
can you post your critical buckling calcs, the assumptions it makes, what restraints and loading it assumes
Are you trying to produce a visualization of what buckling of this cylinder may look like, or are your trying to predict the buckling behavior for structural reasons?