Effect of Axial Profile Modification on the Characteristics of a Finite Length Misaligned Journal Bearing

Abstract

Abstract Misalignment in journal bearings is a common industrial problem which affects the general performance of the bearing. This includes a significant effect on the load carrying capacity of the bearing and the change in the level and shape of the pressure distribution. There are many causes for the presence of misalignment in the practical uses of the journal bearing system, such as deflection of the shaft under high levels of load, manufacturing errors, installation error, and others. In the case of severe misalignment levels, a sharp drop in the lubricant film thickness or even a direct contact may occur between the shaft and the bearing at the edges of the bearing. This paper considers such extreme cases of misalignment, where the introduction of bearing axial profile modification to prevent edge contacts is investigated in detail. A general 3D model of misalignment for the case of a finite length bearing is considered in the analyses, where the Reynolds equation is solved numerically based on the finite difference method. The results reveal that the use of profile modification leads to an improvement in the levels of film thickness and an increase in the load-carrying capacity of the bearing.