On the Influence of Inertia Forces in Turbulent and Laminar Self-Acting Films

A method is given for determining the motion in a fluid film including inertia forces. The method is developed for infinitely long bearings and can be used for both laminar and turbulent flows, as well as for incompressible and compressible lubricants. The obtained results show that for steady films, convective inertia forces lead basically to Bernoulli effects, while for unsteady films inertia forces may influence both damping and stiffness characteristics of the bearing. At the same time it is pointed out that when Bernoulli effects are important, similar effects may occur in the inlet region of the film. A generalization of the method for bearings of finite dimensions is also given.