Syntax:
fix ID group multicontact/halfspace geometric_prefactor gp_value
geometric_prefactor gp_value = gamma gamma is an empirical factor accounting for the geometry
Examples:
fix multicontact/halfspace fix multicontact/halfspace geometric_prefactor 1.8
Description:
Implements the multicontact model by (Brodu et al.) . This model computes a per-contact deformation for each particle based on the other contacts this particles has. A particle i with contact ij has the following new radius (when computing the contact laws with particle j):
r_i + sum_k delta_{ij->ik}
where r_i is the default radius of particle i, sum_k is the sum over all particles in contact with i (k!=j). The delta value is given by
delta_{ij->ik} = - gamma (1 + nu) F_ik / (2 pi Y d_{ik->ij}) * [(n_ik . u_{ik->ij})(n_ij . u_{ik->ij}) + (3 - 4 nu) n_ik . n_ij - (1 - 2 nu) (n_ik + u_{ik->ij}) . n_ij) / (1 + n_ik u_{ik->ij}) ]
where
Restart, fix_modify, output, run start/stop, minimize info:
No information about this fix is written to binary restart files.
fix_modify cannot be used on the parameter of this fix.
Restrictions:
Requires the use of the gran surface model multicontact
Related commands:
Default: none
References:
(Brodu) Brodu, Dijksman, Behringer, Multiple-contact discrete-element model for simulating dense granular media, Phys. Rev. E (2015).