Gran/hertz/history parameters for sand grains


I’ve been trying to develop a simulation that can model a granular chute flow. I did an experimental investigation using sand, and in order to make a good comparison between my simulation and experimental data, I wanted to use values for Kn, Kt, gamma_n, gamma_t, and xmu that are appropriate for sand grains. I have read a couple of research papers, but I’ve yet to find anything specific to sand. Does anyone know what those parameters should be? Additionally, since I have been trying to imitate my physical setup, I have working in SI units; do I need to use LJ units in order to do this correctly?

Thank you very much for your help!

Two comments:

  1. The best place to look for suitable parameterizations is the published literature. Sand should be common enough, although its change in behavior when it contains moisture might be challenging for the kind of granular model available in LAMMPS, if that is relevant to your use case, that is.
  2. LAMMPS should work correctly for any choice of units. The only cases where specific sets of units are required are when a) parameters are read from files and then the units used when writing those files must be used, b) the code in question uses some hardcoded conversion or physical constants (which is rare). Neither of those apply to granular pair styles.