peridynamics eps model


I have a question about the implementation of the eps peridynamics model in LAMMPS

My understanding is that, if the yield stress is very high, the eps model should behave like the lps model, am I right?

I am testing the model by running two simulations: one with the lps model (see attached input file molle.lps) the other with the eps model (see attached input file molle.lps). In both cases, it is exactly the same simulation: a two-dimensional C-shaped rubbery-like material (E=0.01GPa) undergoing compression without breakage (s00 is given a very high value). I imposed a very high yield stress expecting the same result with the lps and the eps model. However, while the lps model works fine and the simulation looks as expected, the eps results show completely unrealistic deformations.

It is not matter of time step or particle resolution. I decreased the time step from 10^-7 to 10^-9 and I tried different resolutions, but the results, basically, do not change. I also run 3D versions of both models, but the situation remains the same.

Am I missing something or am I doing something wrong in the input files? Any help is greatly appreciated

Best Regards

molle.lps (3.19 KB)

molle.eps (3.24 KB)

since there has been no answer yet given on the mailing list, you should assume, that nobody willing to answer has enough knowledge of the details of peridynamics to provide a competent answer. i would suggest you look up the email address(es) of the author(s) of the package in LAMMPS (should be given in the documentation and/or source code or README files) and contact them directly.


Hi Alex,

I’ll do. Thanks for the advice.