Hi
I am trying to simulate a non linear analysis of a free falling object on a steel wire net. Is it possible to do the same in PrePoMax. The material of the net is Stainless Steel. Could anyone please help me to input the material properties of SS as a non linear material ie, strain at different stress level.
Thank you
This would require the use of a nonlinear dynamic step, likely explicit. It’s not yet supported in PrePoMax but you can use the Keyword Editor or export the input file and modify it manually.
To begin with, you can use the bilinear plasticity model and specify just two points - yield stress with 0 plastic strain and an additional point with non-zero plastic strain to define hardening. Then you could expand this model to multilinear but you would need a complete stress-strain curve, for example from a research paper.
How can I simulate the free fall of an object in PrePoMax? Could you please help…
Prepare the model in such a way that the impactor is right above the target. If it’s symmetric, you can model a quarter of the whole system. Mesh the parts and apply the material (include density, elasticity and plasticity). Add static step with step time corresponding to the estimated time of impact. Define boundary conditions - clamp the sides of the target and apply symmetric BCs if needed. Assign rigid body constraint to the impactor. Define contact between the parts. Export the input file, open it in any text editor (e.g. Notepad++), change the static step to dynamic one (following the syntax described in CalculiX’s manual) and define initial velocity for the reference point of the rigid body constraint. In the case of free fall, it can be specified as v=sqrt(2gh).
If the target is a steel wire net, it might be necessary to mesh it with beam elements and then the model would have to be prepared outside of PrePoMax but maybe solid elements will be fine too.
Thank you so much for the reply. Let me try with the input you gave.