External pressure Cylinder buckling
I study the buckling loads of cylinders. I need to find critical buckling, overall buckling, and collapse buckling loads. First, I did a linear buckling analysis and used mode-1 as a geometric imperfection (scale factor = 0.1). I applied 0.03 Mpa of pressure to the cylinder. I obtained a graph using Newton Raphson and the stabilization settings but could not model the behavior exactly. Then I tried the Arc-Length method. It didn't happen again.
Eigenvalue multiplier is 20,306 for 0,001 mpa . So my critical buckling have to be lower 0,0203. Finally ı wanted to see my model behavior for overall buckling and collapse buckling.
Can you help?
Model - R(radius)=500 mm h=1250 mm t(thickness)=1 mm
Top and Bottom simply supported (displacement x=y=z=0)
3-newton raphson -stabilization energy constant 0,001 (initial 200 min 100 max 2000 substeps) result
5-my arclength result(finished 0,63 sn and not converged)
6-true arc length grafic (wanted)