Impact Cutting Model Reference

Like the Simple Failure model and the Constant Rate Damage model, the Impact Cutting model is a damage model for bonded particles. It applies only to fiber-shaped bonded particles modeled with either Particle Clumps or Flexible Fibers. The model breaks a bonded particle into two parts when the user-specified breakage criterion is met. The two resulting bonded particles can then be broken again after the user-specified Breakage Time Interval.

Clumped particles must be organized into fibers: no sphere has more than two bonds with other spheres within the same clumped particle.

The impact cutting model breaks a bond in the simulation if the particle impact velocity magnitude exceeds the user-specified Impact Velocity Threshold. For a fiber or clumped particle with multiple bonds, only one bond breaks at a time if more than one fiber segment (or clumped sphere) satisfies the breakage criterion. In this situation, the bond to break is the one closest to the fiber segment (or clumped sphere) with the maximum value of impact velocity magnitude.

Theory See Impact Cutting Model.
Provided By [physics continuum] > Models > Multiphase Interaction > Phase Interactions > Phase Interaction [n] > Models > Optional Models
Example Node Path Continua > Physics 1 > Models > Multiphase Interaction > Phase Interactions > Phase Interaction 1 > Models > Impact Cutting
Requires

Under Lagrangian Multiphase, select Particle Type: DEM Particles

Under Multiphase Interaction:
  • Select Phase Interaction Topology: DEM Phase Interaction if it has not been automatically selected.
  • Set the First Phase and Second Phase properties of DEM Phase Interaction to DEM Lagrangian phases.
  • Select Optional Models: Hertz Mindlin, Walton Braun, or Linear Spring
  • Optional Models Parallel Bonds or Bonded Particles are not required if the Flexible Fiber model is selected under Lagrangian Phase Models.
Properties Key properties are: Impact Velocity Threshold, Breakage Time Interval. See Impact Cutting Model Properties.
Activates Field Functions Bond Damage, Particle Impact Velocity Magnitude. See Impact Cutting Model Field Functions.

Impact Cutting Model Properties

Impact Velocity Threshold
Specifies a threshold of impact velocity between particle and boundary for bond breakage. The default value is 20 m/s.
Breakage Time Interval
Specifies a time interval between two breakages for the same fiber. The default value is 0.005s.

Impact Cutting Model Field Functions

Bond Damage
The damage to a bond, on a scale from 0 (undamaged) to 1 (broken). See k r in Eqn. (3298).
Particle Impact Velocity Magnitude
The magnitude of the relative velocity between the particle and the wall at the contact point.