Numerical Simulation of Scale Effects in Contacting Rough Surfaces

It is well known that surface topography is composed of multiple length scales. Yet it remains a challenge to ascertain how the various length scales affect the contact area and contact stresses. Several micro-contact models exist in the literature that seek to account for the multi-scale nature of surface topography through fractal or spectral descriptions. A limitation of most such micro-contact models is that they neglect the interaction between asperity contacts. In the current work, a deterministic numerical simulation of contact is performed on the contact between a rigid flat and a rough, elastic surface whose heights vary in a single dimension (i.e., y(x)). A simulated surface profile is created and then “sampled” at several resolutions to create a set of related profiles of various levels of refinement. Contact is investigated with each of the simulated surfaces to gain insight as to the role of various length scales.