Stress concentraion in elastomers

Hi FEGuru,

and thank you for your suggestions.

Just for clarity, are you implying I should switch to some viscoplastic model? (you mention permanent deformations).

And why should that be needed?

I was thimking myself about introducing some time dependancy (as I find physically very unrealistic that such a sharp gradient as the one I am picking would not get relaxed and smeared by rubbers viscosity), but viscoplasticity is a surprise for me.

I would be grateful if you could expand on this.My problem is that results at the singularity are needed (better, results at the location where the singiularity is placed by an incorrect material model)

Thanks

Best Regards

Muzialis

Hi Muzialis,

Yes I was thinking of a viscoplastic model. I dont think adding viscoelastic effects to rubber would relax a strain singularity.

If you want an accurate solution in the vicinity of the singularity then you should also consider eliminating that mathematical singularity (instead of finding a material model that can handle it). You can do that by replacing sharp corners with non-zero fillet radii, or modeling delamination, etc. This approach however will most probably require a fine mesh in the vicinity of the singularity.

FE Guru,

many thanks

Best Regards

Muzialis