Influence of magnetic fluids’ cohesion force and squeeze dynamic effect on the lubrication performance of journal bearing

Abstract

Using the magnetic fluids containing polymer additives as the lubricant with couple stress, this article first develops the lubrication model of the journal bearing considering the couple interaction between its squeeze dynamic effect and its rotating effect. The effects of the squeeze dynamic effect of journal bearing, magnetic fluids' cohesion force, and magnetic fluids' couple stress on the lubrication performance of journal bearing (the load-carrying capacity (S) and its attitude angle (c), the friction coefficient (C f (R/c)), and the side leakage (Q)) has also been studied. The results above show that the maximum dimensionless film pressure (P max) along the bearing centerline increases as the increase of the squeeze dynamical effect parameter (q), magnetic fluids' cohesion force coefficient (g), and magnetic fluids' couple stress parameter (L*); c decreases as the increase of q, the decrease of g, and the increase of L*; S increases as the increase of q, g, and L*; C f (R/c) decreases as the increase of q, g, and L*; Q decreases as the decrease of q, the increase of g, and the increase of L*.

On the behavior of a ferrofluid-lubricated herringbone-grooved hybrid slot-entry bearing

“…The bearing operating/geometric parameters and ferrofluid properties are shown in Table 1 and are chosen from the available literature. 3,4,7,14,15,21,23,27,28,30,31,49 In this study, the rectangular groove shape has been chosen. Furthermore, the influence of the groove orientation angle on the herringbone groove (from 10°to 90°) has also been studied to evaluate the performance of the ferrofluid-lubricated HGJBs.…”

“…Ferrofluid lubricant properties and bearing operating, geometric parameters. 3,4,7,14,15,21,23,27,28,30,31,49 Variation of minimum film thickness ( h min ). Figure 5(a) shows the effect of the herringbone groove angle and magnetic coefficient (ψ) on h min .…”

“…It was reported that the load capacity improves when the bearing operates with a ferrofluid. A study on a fluid film bearing in a high-speed spindle application for a hard disc drive was reported by Zhang et al 6 Hu and Xu 7 used a ferrofluid couple stress model to investigate the behavior of a fluid film hydrodynamic journal bearing and showed that the load capacity of the JBs gets improved due to the magnetic field application. The static performance of a ferrofluid-lubricated journal bearing was investigated by Zhang 8 in terms of load capacity, lubricant flow rate, and pressure variation.…”

“…The earlier reported published studies [1][2][3][4][5][6][7][8][9][10][11][12][13] reveal that the performance of fluid film bearings improves using ferrofluid lubricant. However, the use of a ferrofluid lubricant in a hybrid slot-entry journal bearing is not researched yet.…”

Wind Turbine Lubrication Based on Parallel Control of Multiple Factors

“…The lubrication of a wind turbine should focus on an important mechanical part: the bearing. The wind turbine cannot operate normally, if its bearing is not sufficiently lubricated [2][3][4].…”