Homotopy Analysis of Circular Plates Squeeze Film Bearings Lubricated with Couple Stress Fluids: Piezo-Viscous Model

The piezo-viscous effect is crucial in fluid flows under high-pressure applications such as fluid film lubrication, microfluidics, and geophysics. We have investigated the combined influences of piezo-viscous dependence and non-Newtonian couple stresses on the performance of circular plate squeeze film bearings using Stokes Micro-Continuum theory of couple stress fluids together with the exponential variation of viscosity with pressure. A closed-form solution for film pressure has been obtained using the homotopy analysis method. The numerical results for pressure and load capacity with different values of the viscosity-pressure parameter have been calculated and compared with iso-viscous couple stress and Newtonian lubricants. An enhanced pressure and load capacity are observed in the analysis. The response time for the bearing (plate approach time) has also been calculated and a significant increase is observed.

Investigation the combined effects of wear and turbulent on the performance of hydrodynamic journal bearing operating with couple stress fluids

Purpose The purpose of this paper is to investigate the combined effect of wear and turbulence on the performance of a hydrodynamic journal bearing operating under Newtonian and couple stress fluids (CSF). Design/methodology/approach The analysis consists of a modified Reynolds equation of incompressible thin viscous films, and the film thickness model taking into account the wear effect. The governing equation was solved numerically using the finite difference approach. Findings The effect of both the wear parameter and the local Reynolds number on the performance characteristics of bearing has been presented and discussed. The obtained results observed that the characteristics of the intact and worn bearing in turbulent and laminar have been enhanced due to the non-Newtonian fluid (CSF) effect. Also, the results display that bearing worn and the turbulent regime cannot be neglected in calculating the performance characteristics of the bearing lubricated with Newtonian and non-Newtonian fluids. The results achieved from this study, specify that the bearing characteristics are significantly affected by these effects. Originality/value The paper investigates the behavior of hydrodynamic bearings considering different aspects simultaneously is interesting, and the application meets the current needs of improvement in modeling hydrodynamic bearings under different conditions.

Magnetohydrodynamic effects on finite and infinite slider bearings

This paper presents a numerical investigation of lubricating slider bearings with conducting couple stress fluids using externally applied magnetics fields. The modified two-dimensional magnetohydrodynamic couple stress Reynolds-type equation is obtained. This governing equation is resolved numerically by using finite difference scheme, which involves the Gauss–Seidel method to compute the bearing characteristics. Numerical results using different considered values of the couple stress and Hartman number are presented. These results demonstrate that the transverse magnetic field and couple stress effects are significant.