1
W H I T E P A P E R
Rocky DEM's flexible fiber model includes plastic deformation effects, anisotropy, and an
integrity failure model, which allow you to cover a wider range of fiber materials in more complex
equipment and with higher fidelity.
This white paper covers Rocky DEM's flexible fiber model as well as some application examples.
How does Rocky model flexible fibers?
Flexible fiber modeling in Rocky follows the approach described by Guo et al. [1]. In this
approach, a flexible fiber is built by connecting sphero-cylinders by means of joints, as depicted
in Figure 1.
Figure 1. Schematic drawing of a fiber composed of several sphero-cylinder elements.
An auxiliary entity with elastic and viscous properties, a joint connects two adjacent sphero-
cylinder elements.
Initially, the centers of the hemispherical ends of adjacent elements coincide, and the joints
are undeformed. However, when the elements move, the relative movement between them may
produce linear deformations (normal and tangential) and/or angular deformations (bending
and torsion) on the joints, as shown in Figure 2.
In response to these deformations, forces and moments are induced and exerted on the adjacent
elements to resist these deformations.
Figure 2. A fiber joint in its undeformed initial state (Left). A fiber joint in a deformed state showing the relative movement between
elements and the bending deformation (Right).
Modeling real fibers: everything you need to
know about the Rocky DEM flexible fiber model
