Static and dynamic characteristics of journal bearings with non-newtonian palm-based oils

This paper presents the investigation of the static and dynamic characteristics of hydrodynamic journal bearings lubricated with non-newtonian palm-based oils. The palm oil was mixed with 0.2% ZDTP and 1% ZDTP to reduce oxidation and increase lubricity. In this study, the power law model is proposed as a rheology model of palm-based oil and the relationship between the shear stress and shear rate was obtained experimentally. The time-dependent modified Reynolds equation, and adiabatic energy equation were formulated for full circular bearings. Finite difference method was used to calculate both the static and dynamic characteristics of the bearings such as pressure distribution, temperature distribution, attitude angle, stiffness and damping coefficients. The results shows that the palm-based oils have potential to use as a biodegradable lubricant.