Multiphysical modeling of third-body rheology

Abstract

As the rheology of the third body does not only depend on its mechanical properties, classical discrete element simulations are not capable of modeling its flows. Consequently to take into account the third body's mechanical, thermal and physicochemical properties, an extended discrete element approach is proposed and applied to the simulation of third body flows. Each extension of the standard DEM model is compared to experimental results. The extended model's efficiency is demonstrated by using an arbitrary physicochemical law that simulates different types of behaviour observed experimentally.

Thermo-Mechanical Investigations of a Tribological Interface

“…This approach has been widely used for tribological application dealing with mechanical [21], thermal [22] or more complex behaviors [22]. The approach differs from other approaches offered in the literature by its both implicit time integration and contact resolution, guaranteeing a converging stability and avoiding numerical tuning.…”

“…For debris particles, interactions are governed by a nonsmooth contact cohesive law used to reproduce reversible cohesion due to physicochemical effects [22]. Let d w be the attraction distance between two particles, g, the gap between particles and r n the normal contact force; one obtains a linear complementarity problem such that:…”

“…Nevertheless, as proposed in [22], other forms of energy transformation, such as convertion into vibration, phase transformation or volumetric heat by plastic strain [8], are not considered, and all the dissipated mechanical energy is converted into thermal energy (i.e., w ¼ 1). Note that even if a value of w 6 ¼ 1 changes the amount of generated heat, it will be changed in the same way for all simulations and, consequently, does not affect quantitative comparisons.…”

“…Note that Eq. (8) is extended to cohesive contact by adding up the contact force with the absolute value of the cohesive force c [22].…”

Numerical tribology of a dry contact

“…This kind of approach allows linking every physical feature within a single simulation [145,146]. The limits of these approaches depend on the experimental data used feed the models.…”