Modeling of an inflatable tube - buckling and folding

Andrea_22029

Hello everyone,

I'm trying to perform a non linear buckling analysis on an inflatable pressurized tube.

I set a satisfying model in Optistruct using PSHELL elements (with a MAT1 material) with a NLSTAT-LGDISP analysis, and it matches well experimental points also in post-wrikling state.

Now I would run a non-linear buckling analysis in order to predict the maximum axial and bending load on the beam, so I found that only with Radioss it is possible. Next, I would be interested in modeling the folding and unfolding of the beam in an appropriate box in order to simulate the behaviour.

The questions are:

1) am I right? are there example about modeling of inflatables in Radioss or should I use another product? It is possible to run a non-linear buckling analysis with Optistruct?

2) I'm new in Radioss: are there some tutorials about folding and unfolding of inflatables by increasing of pressure? It is necessary to model a fluid-structurer interaction in this case?

Thank you for your attention

Andrea

Adriano_Koga

Radioss would be a good option for running post-buckling, in explicit, for sure.

But OptiStruct has also RIKS method, and might be helpful for your analysis too, if you want to run Implicit.

OS has also NL Explicit method, so it's another option.

I'm attaching a OS Explicit model if you want to try.

garrafa_buckling_remeshed_sym_t0.2mm_CST1e-6.zip

L_NL_RIKS_NLSTAT_100N.fem