Learning Forum

[Nabuchadresar2]

Hi guys, I'm again! xD

My name is André Moura, i'm try running a hyperelastic simulation. I have the uniaxial test data from experimental test. After some troubles and changes we reach some "good" results.

[peteroznewman]

All material testing is done by taking data over a Gauge Length. That is a portion of the sample where the section is uniform for some distance before and after the Gauge Length.nThe wider portions on the ends where the clamps go is always excluded.nThe strain that occurs in the Gauge Length is measured by an instrument called an Extensometer. That measurement is now done by a calibrated camera measuring the displacement of dots marking the surface of the specimen.n

[Nabuchadresar2]

Yes, the area 'A' has been excluded, it was the first simplification. nWe use a extensometer like this (we have a more old than this) on lab (I have no photo now because lab is closed as the pandemic).nSo, can I exclude the 'B' area too?nThanks a lotn

[peteroznewman]

Yes, exclude the B area from the simulation. But how exactly are you going to do that? You can't just have a fixed support at the cut face. You need to allow the section to get smaller the way it does when you have area B.nUse three planes of symmetry and keep 1/8 of the narrow center section. The face opposite the center plane cut will have a displacement in Y only, leaving X and Z Free (assuming Y is vertical).n