Theoretical analysis of jornal bearings lubricated with non-Newtonian fluid based Carreau viscosity model

The static and dynamic characteristics of journal bearings lubricated with non-Newtonian fluids based on Carreau viscosity model have been investigated theoretically. The time-dependent modified Reynolds equation and the adiabatic energy equations have been formulated using Carreau viscosity model. The simultaneous system of modified Reynolds and adiabatic energy equations were solved numerically with boundary conditions using finite difference technique. The linearized bearing reactions and the journal motion can be approximated to obtain the spring and damping coefficient. Static characteristics are presented as pressure profile, temperature profile, load carrying capacity and the coefficient of friction with varying the eccentricity ratio. The stiffness coefficients, damping coefficients and the stability of the journal bearing are investigated with varying the parameters of the non-Newtonian fluid model. In this study, the shear rate of non-Newtonian lubricant and the model parameters have significant effects on the characteristics of journal bearings lubricated with the non-Newtonian fluids.