Investigating the steady state characteristics of noncircular journal bearings lubricated with ferrofluid under concentric finite wire magnetic field

Abstract

The aim of the present work is to investigate the steady state performance of noncircular hydrodynamic two, three and four lobe journal bearings, lubricated with ferrofluid under concentric finite wire magnetic field. Applying momentum and continuity equation, for ferrofluid under the applied magnetic field, modified Reynolds equation is obtained. Assuming linear behaviour for the magnetic material of the ferrofluid, the Reynolds equation is solved, using finite element technique to obtain pressure distribution then applied to study the effect of magnetic lubricant on various bearing performance characteristics such as load capacity, attitude angle, friction coefficient, friction force and side leakage flow. The results indicate with increasing magnetic force coefficient, side leakage in noncircular bearings and friction coefficient is significantly reduced and improvement in load bearing capacity can be seen at the most values of eccentricity ratio, especially in two lobe noncircular bearing. The results also show that the eccentricity ratio has an effective influence on bearing performance characteristics, if the magnetic field and geometric configuration are selected properly.