A model of hydrodynamic bearings with circumferential parallel arranged grooves

Abstract

A model is proposed to describe and analyze hydrodynamic bearings with circumferential parallel arranged grooves along any arbitrary groove curve. The Reynolds equation is solved with finite volume method, and the additional terms of the discretized equation for any arbitrary groove curve are deducted. With the model, any groove curve could be characterized by setting an array of inclination angles, and dash-shape grooves can also be modelled by setting the matrix of flag variables reflecting whether it is in the groove. Based on the model, the transient behaviors of four groove types are analyzed by Runge-Kutta method, with the pressure distribution, rotor's center orbit and leakage flow obtained. An experiment is conducted to validate the model. Results show that the dash-shape grooves, which are asymmetrical herringboned and intermittent, have both advantages of stability and sealing. The experimental and numerical results of pressure and leakage flow show good agreement in general. The model proposed in this paper will facilitate the design of grooved hydrodynamic bearings, as different groove types can be analyzed and compared by the same model.