EHD Effect on the Dynamic Characteristics of a Journal Bearing Lubricated with Couple Stress Fluids

Authors: B. Chetti, W. A. Crosby

Abstract:

This paper presents a numerical analysis for the dynamic performance of a finite journal bearing lubricated with couple stress fluid taking into account the effect of the deformation of the bearing liner. The modified Reynolds equation has been solved by using finite difference technique. The dynamic characteristics in terms of stiffness coefficients, damping coefficients, critical mass and whirl ratio are evaluated for different values of eccentricity ratio and elastic coefficient for a journal bearing lubricated with a couple stress fluids and a Newtonian fluid. The results show that the dynamic characteristics of journal bearings lubricated with couple stress fluids are improved compared to journal bearings lubricated with Newtonian fluids.

Keywords: Circular bearing, elastohydrodynamic, stability, couple stress.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1126145

References:

[1] T. T. Ariman, N. D. Sylverster, “Microcontinuum fluid mechanics-a review” Int. J. Eng. Sci, Vol. 11, pp. 905-930, 1973.
[2] T. T. Ariman, N. D. Sylverster, “Application of microcontinuum fluid mechanics” Int. J. Eng. Sci., Vol. 12, pp. 273-293, 1974.
[3] V. K. Stokes, “Couple stresses in fluids, The Physics of fluids” Vol.9, pp.1709-1715, 1966.
[4] P. Sinha, C. Singh, “Couple stresses in the lubrication of rolling contact bearing considering cavitation” Wear, Vol.67, pp. 85-91, 1981.
[5] J. Lin, “Effects of couple stresses on the lubrication of finite journal bearings” Wear, Vol.206, pp. 171-178, 1997.
[6] A. A. Elsharkawy, L. H. Guedouar, “An inverse solution for finite journal bearings lubricated with couple stress fluids” Trib. Int., Vol.34, pp. 107-118, 2001.
[7] S. T. N. Swamy, B. S. Prabhu and B. V. A. Roa, “Stiffness and damping characteristics of finite width journal bearings with a non-Newtonian film and their application to instability prediction, ” Wear, Vol.32, pp. 379-390, 1975.
[8] J. Lin, “Linear stability analysis of rotor-bearing system: couple stress fluid model” Computers and Structures, Vol.79, pp. 801-809, 2001.
[9] S. K. Guha, “A theoretical analysis of dynamic characteristics of finite hydrodynamic journal bearings lubricated with coupled stress fluids” Proc. Instn. Mech. Engrs, Vol.218, pp. 125-133, 2004.
[10] W. A. Crosby and B. Chetti, “The static and dynamic characteristics of two-lobe journal bearings lubricated with a couple stress fluid, ”Tribology Trans., Vol.59, pp. 262-268, 2009.
[11] G. S. Nada, G. T. Abdel-Jaber and H. S. Abdo, “Thermal effects on hydrodynamic journal bearings lubricated by magnetic fluids with couple stresses” Int. J. Mech. Mechtrn. Eng, Vol.19, pp. 12-20, 2012.
[12] S. C. Jain, R. Sinhasan and D. V. Singh, “The Performance characteristics of thin compliant shell journal bearings” Wear, Vol.81, pp. 251-261, 1982.
[13] S. C. Jain and Sinhasan, “Performance of flexible shell journal bearings with variable viscosity lubricants” Trib. Int., Vol.16, pp. 331-339, 1983.
[14] Y. Zhang, “Linear Deformation of a journal bearings and its relationship to hydrodynamic pressure” Wear, Vol.115, pp. 41-52, 1987.
[15] H. N. Chandrawat and R. Sinhasan, “A Study of steady state and transient performance characteristics of a flexible shell journal bearing” Trib. Int., Vol.21, pp. 137-148, 1988.
[16] R. Sinhasan and K. C. Goyal, “Elastohydrodynamic studies of circular journal bearings with non-Newtonian lubricants,” Trib. Int., Vol.23, pp. 419-428, 1990.
[17] U. M. Mokhiamer, W. A. Crosby and H. A. El-Gamal, “A Study of a journal bearing lubricated by fluids with couple stress considering the elasticity of the Liner” Wear, Vol.224, pp. 194-201, 1999.