Effects of Design and Assemble Parameters on Performance of Noncircular Lobed Journal Bearings Lubricated with Micropolar Fluid

It is now a well-recognized fact that bearings play a vital role in the performance of any rotor bearing system. Though the plain journal bearing is the oldest and a general purpose bearing configuration, it does not suit the requirements of modern high speed rotating systems and precision machine tools. In such specialized applications, the plain journal bearing has mostly been replaced by noncircular two and three lobe bearings which exhibit superior dynamic performance. In contrast to the plain circular bearing, noncircular journal bearing may be oriented in various ways with respect to a given direction of external load. This orientation may be described in terms of an angle, which in the present work has been referred to as the mount and tilt angles. In the present work applying GDQ method, analyses of micropolar lubricated circular and noncircular two and three-lobe journal bearings, are presented. Effects of micropolarity characteristics of lubricant, design and assemble parameters on the performance parameters of these bearings have been investigated. In general, results show that micropolar characteristic parameters of the lubricant improve the performance of the circular and noncircular bearings. Also it is observed that in the noncircular bearing the effect of mount and tilt angles is generally marginal. of the two types of bearings considered, the two lobe bearings are most sensitive to mount and tilt angles. However, the mount and tilt angles are assemble and design parameters, but sometimes they can be selected just to meet some specific operation goals.