Abstract

There is always a demand in the industry sector to increase the efficiency of machine components to reduce wear and tear. This paper presents the numerical solution to the study of Elastohydrodynamic lubrication point contact for sliding/rolling bearing where the viscosity of the lubricant is non-Newtonian. The assumption that a lubricant is Newtonian reduces validation of the model hence the Reynolds-Eyring model in this research will incorporate the non-Newtonian nature of the lubricant of the bearing. The mathematical model comprises of Reynold-Eyring equation, film thickness, load balance, lubricant viscosity and lubricant density equations together with their boundary conditions. The Reynolds-Eyring equation governing the flow is non-linear hence the finite difference method numerical technique is used to discretize it together with the other two dimensional equations. These equations are solved simultaneously and Matlab software is used simulate the results. The film thickness and pressure profiles with various loads and speeds are presented. The findings note that an increase in load lowers the pressure and film thickness while an increase in the speed results to a direct increase in pressure and film thickness. A pressure spike is also noted at the exit of the bearing.

Highlights

  • Lubrication is an important aspect for modern machine so that they can work efficiently and have long life

  • The Reynolds equation which was derived by Osborn combines both the continuity and momentum equations to a single equation that describes the pressure of fluid [2]

  • Many rheological models have been proposed to incorporate the non-Newtonian nature of lubricants during mathematical modelling

Read more

Summary

Introduction

Lubrication is an important aspect for modern machine so that they can work efficiently and have long life. Elastohydrodynamic lubrication (EHL) is an important aspect of research in lubrication theory primarily in heavily loaded contacts. Many rheological models have been proposed to incorporate the non-Newtonian nature of lubricants during mathematical modelling They include the Reynolds-Eyring model, Johnson-Tevaarwerk model, power-law model among others [4]. The study [10] used the numerical finite difference technique to discretise the Reynolds equation and the viscosity equation for the rheology model in their research. The research study [11] solved both the Reynolds and energy equation using the finite difference method. The numerical study [12] and [13] in their research of hydrodynamic lubrication of an inclined pad thrust bearing used the finite difference method to solve both the pressure and energy equations. The Reynolds-Eyring model will be solved using the finite difference method

Mathematical Formulation
Governing Equations
Reynolds-Eyring Equation
Lubricant Density Equation
Non-Dimensionalization
Numerical Solution
Pressure Profile
Effect of Eyring Parameter on Pressure
Effects of Speed on Pressure and Film thickness
Effects of Load on Pressure and Film Thickness
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call