Numerical Simulation of the Lubrication of the Head-Disk Interface Using a Non-Newtonian Fluid

The prospect of contact and near-contact recording in magnetic hard disk files naturally leads to reduced flying heights of the read-write head over the rigid disk. To avoid dry contact at these low head-to-disk spacings, a lubricant should be used to minimize wear and maximize reliability. Since fluids generally have a much greater viscosity than air and very large shear rates develop under the slider, it is believed that a fully flooded interface can only be practically possible if the fluid possesses a non-Newtonian character with a significant amount of shear-thinning. In this paper, we present results from extensive numerical simulations of the fully flooded head-disk interface using the finite element technique. This approach has proven very successful in calculating a wide variation of slider geometries for various fluid nonlinearities.