Hello Users,
I have been trying to use the EPS model but I am having troubles. It seems that once the yield condition is true, the model is unstable, i.e. stresses become very high and the model explodes.
I have done several things such as very small timestep, large s00, and slow strain rate but nothing works.
The material properties are correct, strain rates are actual experimental rates and the timestep is 100 times small than the CFL condition. These parameters work with the LPS model and they work in the actual peridynamics code Peridigm.
This problem has been brought up several times on the mailing list:
http://lammps.sandia.gov/threads/msg47371.html
http://lammps.sandia.gov/threads/msg62328.html
https://sourceforge.net/p/lammps/mailman/message/32583079/
I have attached a LAMMPS input for a cylinder in a tensile load. This model becomes unstable when things begin to yield; the compute plasticity/atom has values >10000.
If anyone has a working input, it would be very helpful to see, but at this point I am convinced that there is something wrong with the actual LAMMPS code and not my simulation.
Thank you for the help,
Steve
eps.lmp (4.05 KB)