Walton Braun Model Reference

The Walton Braun model is an elastic-plastic contact model, which is useful in situations where a collision between two bodies includes plastic deformation.

This situation is typical for materials like grain, soybeans, or coal where the collisions lead to material deformation and the impact energy is dissipated during the collision.

In order to simulate inelastic material, Simcenter STAR-CCM+ provides a hysteretic plastic-elastic contact model that is based on the formulation of Walton and Braun ([117], [118]).


Theory	See Walton Braun Hysteric Contact Model.
Provided By	[physics continuum] > Models > Multiphase Interaction > Phase Interactions > Phase Interaction [n] > Models > DEM Contact Model
Example Node Path	Continua > Physics 1 > Models > Multiphase Interaction > Phase Interactions > Phase Interaction 1 > Models > > Walton Braun
Requires	Optional Models: Lagrangian Multiphase Optional Models: Discrete Element Method (DEM) Multi-Phase Interactions: Multiphase Interaction selected automatically Under Multiphase Interaction, select Phase Interaction Topology: DEM Phase Interaction if it has not been automatically selected.
Properties	Static Friction Coefficient, Rolling Friction Coefficient, Normal Restitution Coefficient, Tangential Restitution Coefficient. See Walton Braun Properties.
Activates	Physics Models	Optional Models and specifically the Rolling Resistance model

Walton Braun Properties

These property settings are available for you to calibrate when comparing results in Simcenter STAR-CCM+ to your experimental results.

Static Friction Coefficient: $C_{f s}$ (see Eqn. (3254)).
Rolling Friction Coefficient: $μ_{r}$ (see Eqn. (3276)).
Normal Restitution Coefficient: $C_{n r e s t}$ See Eqn. (3257).
Tangential Restitution Coefficient: $C_{t r e s t}$ See Eqn. (3258).
Stiffness Ratio: Controls the ratio of release and accumulation of energies during loading and/or unloading, therefore this property must be a non-negative, non-zero value. Setting this property to 0 means the material is perfectly plastic and it only deforms. The Walton Braun model is not suitable for simulating such physics.
Yield Strength Fraction: Also known as yield stress fraction (see Eqn. (3272)).
Freeze Tangential Force: When Off, includes tangential force in the calculations.
Freeze Torque: When Off, includes torque in the calculations.