Dynamic Behavior of a Foil in the Presence of a Lubricating Film

Abstract

Equations for the oscillations of a foil over a lubricating fluid film are derived and are simplified by a small parameter expansion. A few particular cases are discussed, and a linearized solution is obtained for the case of a massless, perfectly flexible foil moving at a speed U over an incompressible film. The solution reveals the interesting phenomenon that small disturbances in the film thickness, as well as symmetrical large disturbances, propagate at a speed U/2.