Squeeze flows in liquid films bound by porous disks

Squeeze flows in liquid films between a porous disk and an impermeable disk generated by the relative motion of the disks are analysed. Two configurations that differ by the arrangement of (im)permeable external surfaces that bound the porous disk (i.e. not in contact with the liquid film) are considered. Such configurations allow for bearings with tuneable load-bearing characteristics and are also encountered in joint lubrication, adhesion, printing and composite manufacturing. In the present study, flow in the porous disk is governed by Darcy’s law and flow in the liquid film is described using lubrication theory. The present analysis also allows for slip between the liquid film and porous disk. Analytical solutions of the coupled system of equations governing flow in the liquid film and the porous disk are found. Under certain conditions, somewhat unexpected flow patterns are observed in the porous disk. The load-bearing capacity for both configurations is also examined as a function of the permeability and geometry of the permeable disk.