Elastothermohydrodynamic effects in elliptical bearings

Abstract

In this paper, the effects of bearing liner elastic deformation and lubricant viscosity variation with pressure and temperature are studied for an elliptical bearing. The three-dimensional momentum and continuity equations and three-dimensional elasticity equations are solved to obtain pressure in the lubricant flow-field and deformation in the bearing liner. The energy equation and Fourier heat conduction equation are used to obtain the temperature distribution in the fluid film and the bearing body. Simultaneous solutions of fluid flow, elasticity and thermal equations are obtained using a finite element method and a direct iteration scheme. A range of values of the deformation coefficients are presented for various lubricants taking into account the flexibility of the bearing liner, the static and dynamic performance characteristics of an elliptical journal bearing operating at different eccentricity ratios. The lubricants presented fall into three categories: (i) isoviscous, (ii) piezoviscous, and (iii) thermopiezoviscous (viscosity dependent on both pressure and temperature).