Peridynamics eps model not stable

Hello Users,

I’m attempting to use the peridynamics eps model however it does not seem to be stable with my parameters. It either blows up or the tensile bar starts to bend oddly. I was wondering if anyone can provide some input as to what might be wrong.

I’m using the material properties from the Mitchell eps paper. It almost seems like the timestep is leading to the instability but I’m using a very small timestep (1e-9 s), while the Courant-Friedricks-Lewy conditions give a timestep around 1e-8 s.

I’ve attached my input file. The regions are creating a tensile bar.

Thanks for the help and if any other information is needed, don’t hesitate to ask.

Best regards,

Abby (1.92 KB)