Combined influence of geometric irregularities of journal and turbulence on the performance of four-lobe hybrid journal bearing

Abstract

The present study deals with the influence of geometric irregularities of journal (barrel type, bellmouth type and undulation type) on the performance of capillary compensated four-lobe multirecess hybrid journal bearing system operating in the turbulent regime. The Reynolds equation governing turbulent flow of lubricant has been modified by using the turbulent lubrication theory of Constantinecscu and has been solved by using the finite element method. It has been observed that turbulence deteriorates the bearing stability threshold speed margin. Further, the computed results demonstrate that the four-lobe bearing (δ=0.8) provides higher value of fluid film stiffness and stability threshold speed margin than the circular bearing operating in turbulent regime.

Effect of CSL on the characteristics of six-pocket hybrid irregular journal bearing

“…The characteristics parameters of bearing system are computed in postprocessing. In order to authenticate the developed program, the results of the program were compared with the results by Mokhiamer et al, 24 Metman et al, 25 and Jain and Sharma 8 for CSL operated hydrodynamic JBS, hydrostatic JBS, and hybrid JBS with capillary restrictor, respectively. A close agreement in present and published results is noticed as shown in Figure 3(a) to (d).…”

“…The studies [3][4][5] considered the influence of journal's irregularities on the characteristics parameters of hydrodynamic JBS. Recently, the studies [6][7][8][9][10][11] investigated the effect of journal's irregularities on the behavior of four-pocket hybrid JBS including the influence of micropolar lubricant, 11 power law lubricant, 6 ellipticity of bearing 7 and turbulence, 8 and journal misalignment. 9,10 The studies [3][4][5][6][7][8][9][10][11] reveal that the bearing characteristics (viz.…”

Experimental evidence of a two-axial groove hydrodynamic journal bearing under severe operation conditions

“…The thermal behaviours of a cylindrical journal bearing have been widely studied for several decades. THD and TEHD models as well as experimental activities have been performed to fully understand the behaviour of oil-lubricated [1]- [10] , gas-lubricated [11]- [13], water-lubricated [14]-Ref456430265 \r \h [18], or hybrid ef462221077 \r \h [19]- [21] journal bearings.…”

Dynamic analysis of a 2-lobe geometrically imperfect journal bearing system

“…These irregularities are reported by various researchers in their theoretical and experimental analysis of journal bearing systems. [9][10][11][12][13][14][15][16][17][18][19][20][21][22] Salama 9 experimentally and theoretically examined the long wave undulation effect on the parallel-faces thrust bearing performance. The result of his study indicates that the optimum bearing capacity occurred at a constant ratio of wavelength to amplitude.…”

“…Very recently, Jain and Sharma 21,22 examined the influence of geometric irregularities of journal on the performance of a 2-lobe hybrid journal bearing operated with power law lubricant 21 and turbulence effect on 4-lobe hybrid journal bearing, 22 respectively. It has been observed that bearing with barrel shape journal exhibits higher value of stability threshold speed margin than other types of irregularities in both bearing systems (2-lobe and 4-lobe hybrid journal bearing).…”