Unrealistic results in Cosmos tests

So im testing a bicycle frontend and im stumped. The results seem to be completely unreliable.

I tested a 40x1.5mm 6063-t6 tube for compression, using a force of 100kgf and i got a FOS of 0.0012. I've built a few frames before, i know that me stepping on a tube will not crush it.

Any feedback is appreciated and sorry for spamming today.

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2 Answers

See my previous comments, and
1) Try not to use cosmos in case of composites, use something elce
2) Do mesh convergence analysis to find the right mesh size
3) Make all elements to be nice and perform a mesh check untill satisfaction
4) Spot all stress concentrators including holes etc. Mesh them specifically for each type of concentrator (if you do not do, in linear theory the stress value in those points is infinite)
5) Solve the problem with right all above
6) Perform a stress values extraction in points of stress concentration (specific procedure for each type)
7) If you've done everything above, you still have to test it with linear beam theory and free-body diagram, and the result have to be conservative (free-body should give FOS lower then FEM)
8) Once you've done everything above, welcome to the world of stress mechanics

 
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