particle_contact_model command

Purpose

Command for setting particle pairwise interactions.

Note

This command is supported by Aspherix GPU.

Syntax

particle_contact_model keyword value

Keywords:

Keyword

Description

style
type of pair potential
default: gran

normal
contact model in normal direction; off or normal style (see normal models)
default: off

tangential
contact model in tangential direction; off or tangential style (see tangential models)
default: off

cohesion
cohesion model; off or cohesion model style (see cohesion models)
default: off

rolling_friction
rolling friction model; off or rolling friction model style (see rolling friction models)
default: off

surface
surface model; off or surface model style (see surface models)
default: default for sphere, multisphere, fiber, bonded and fragments. Other shapes trigger specific surface model styles.

settings
multiple setting_name / setting_value pairs can be added; available settings depend on models
default: off
settings related to the particle-particle contact area calculation are available for all models: see here

At least one contact model between normal, tangential, cohesion, rolling_friction must be selected.

Examples

particle_contact_model normal hertz tangential history cohesion off rolling_friction epsd2 settings computeDissipatedEnergy on
particle_contact_model normal hertz tangential history surface multicontact

Description

This command sets the model(s) that Aspherix® uses to compute pairwise interaction forces. In Aspherix®, the pair forces are defined between pairs of particles that are within a cutoff distance and the set of active interactions typically changes over time. The different pair potential can be selected via the style keyword; see this page for the full list of pair styles defined in Aspherix®.

The normal, tangential, cohesion, rolling_friction and surface keywords define the contact, cohesion, rolling friction and surface models for pair potentials gran and wall/gran; see this page for the full list of model styles defined in Aspherix®. The settings keyword allows to modify some options of the above-mentioned models; e.g., see this this page for the settings referring the normal model Hertz.

Warning

The pair style gran is employed by default and should be changed only by advanced users.