Behavior of micropolar lubricated lobe bearings: influence of non‐circularity parameters

Abstract

Purpose -The purpose of this paper is to analyse the static performance characteristics of lobe journal bearings lubricated with a micropolar fluid, considering effect of non-circularity. Number of lobes and their preload value are the non-circularity parameters considered in the present study. The bearings undertaken for the investigation are two, three and four-lobe symmetric journal bearings with finite width. Design/methodology/approach -For this purpose, modified form of Reynolds equation is derived, based on Eringen's micropolar fluid theory and it is solved numerically using finite element method (FEM). The effect of the non-circularity parameters of bearings on the steady-state performance characteristics such as load carrying capacity, attitude angle, coefficient of friction and side leakage flow are presented and discussed.Findings -The results show that the number of lobes and their preload value can influence the performance of lobe bearings. It is seen that, in order to provide certain improvement over simple cylindrical bearings, the non-circularity parameters of lobe bearings must be chosen correctly. There is no single optimum profile for multi-lobe bearing application. Originality/value -Lobe bearings, compared with simple circular bearings, offer several geometric parameters to designers. These parameters must be chosen correctly, so that the requirements of a specific application can be fulfilled.

Dynamic stability of micropolar lubricated hydrodynamic offset-halves journal bearings

“…Nekoeimehr et al. 15 used the micropolar fluid theory for the study of various geometries of non-circular bearing, i.e., effect of non-circularity parameters on the performance of lobed bearings. They concluded that performance of such bearings is dependent on the number of lobes and preload values.…”

Performance characteristics of two-lobe pressure dam bearings with micropolar lubrication

“…Nekoeimehr et al. 7 presented the effect of non-circularity parameters on lobed bearings. They found that the number of lobes and their preload values are the key factors which affect the performance of such bearings.…”

“…Research studies [6][7][8][9][10][11][12][13][14] in the area of non-circular bearings are discussed below. Non-circular bearings (two-lobe, three-lobe and four-lobe bearings) were examined by Rahmatabadi et al 6 They evaluated various static characteristics of these bearings and compared them.…”

“…It was observed that there was a significant increase in the static characteristics (such as load and attitude angle) of lobed bearings with micropolar lubrication. Nekoeimehr et al 7 presented the effect of non-circularity parameters on lobed bearings. They found that the number of lobes and their preload values are the key factors which affect the performance of such bearings.…”

Influence of Micropolar Lubricants on Asymmetric Slot-Entry Journal Bearings

“…They found that the performance of bearings can be enhanced by selecting the proper bearing orientation angle. Recently, Nekoeimehr et al [13] presented an analysis of lobe bearings under micropolar lubrication. Later on, Sharma and Ram [14] analyzed influence of parameters of micropolar lubricant on symmetric slot-entry hybrid journal bearing.…”