Effect of Change in Radial Clearance on Pressure Variation of Fluid in Hydrodynamic Journal Bearing

Abstract

This work entails the parametric study of the effect of the change in bearing radial clearance with pressure variation of the fluid (lubricant) in a hydrodynamic journal bearing was carried out. The classical Reynolds Equation was used to represent the pressure behaviour in the bearing. This study was carried out using the Galerkin Finite Element Method (GFEM). The result obtained shows that the pressure increases from the ambient pressure which is taken to be zero and increases significantly till 145.3737⁰. At this point, the pressure is maximum with 1.955 MPa and then drop until it gets to 180⁰ where the pressure equals the ambient pressure. Between angular displacements of 180⁰ and 360⁰ there were also pressure variations which were equal in magnitude with those between 0⁰ and 360⁰ but with different direction. From the foregoing, it is observed that as the radial clearance increases, the pressure in the bearing drops significantly. Therefore, in the design of journal bearings, the radial clearance should a high as possible to reduce the pressure in the bearing. The result obtained shows a strong positive correlation with existing result in literature.

Keywords

• Hydrodynamic lubrication,Journal bearing,weak formulation,Radial clearance,Finite Element Method

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