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[Scooped]

Hi all,

I have a bumper system set up: it has a beam, an energy absorber, two crash boxes which support it and then a 'car beam' set to the car weight. It is hit with an impactor which pushes the bumper system backwards, there is a tiny amount of plastic deformation. The beam does however seemingly oscilate forever, and I was wondering if there were any settings i could change which would cause it to stop oscillating and settle. It is mainly the beam i'm wanting to record data for, but is there is a way which I could make sure everything settles naturally that would be best, if not just the beam is fine too.

Thanks

p.s

I've attached some photos of my assembly and what the graphs look like.

[1shan]

,nThe material damping is implicitly accounted via non linear plastic deformation effects( and other effects). Given that unlike the linear dynamic analysis there is no parameter which defines material damping. Have you used any plasticity models or erosion controls to define failure/ non linear behavior? Also, if you are in explicit you could use materials which support strain rate effects, (Johnson Cook) which would cause energy to dissipate. The oscillations are in my opinion due to materials operating only in elastic range. You could also check these discussions https://forum.ansys.com/discussion/21167/how-to-add-material-damping-in-ansys-explicit-dynamics and https://forum.ansys.com/discussion/11549/car-bumper-simulation.nnRegards,nIshan.n