Fluid–Structure Interaction Lubrication Analysis of Compliant Journal Bearing Lubricated With Non-Newtonian Plastic Fluid

Abstract

High-viscosity plastic fluids and polymer liners are expected to improve the lubrication and load-carrying performance of low-speed and heavy-load journal bearings. The objective of this article is to investigate the elastohydrodynamic lubrication performance of compliant journal bearings lubricated with non-Newtonian plastic fluids (following the Herschel–Bulkley model) using computational fluid dynamics (CFD) and fluid–structure interaction (FSI) methods. The following data are obtained: fluid film pressure, total bearing deformation, cavitation volume fraction, bearing capacity, and coefficient of friction. The simulation results closely agree with the data reported in the existing literature. A comparative analysis of the lubrication characteristics of journal bearings with Babbitt metal, PEEK, and PTFE liners at various rotational speeds is presented. The effects of yield stress, power-law index, elastic modulus, and liner thickness on the lubrication characteristics are investigated. The results indicate that the power-law index of non-Newtonian plastic fluids has a greater influence on bearing lubrication performance than the yield stress. Increasing the power-law index could improve the bearing capacity and reduce the coefficient of friction. This research provides a theoretical basis for the application of non-Newtonian plastic fluid-lubricated polymer journal bearings in low-speed and heavy-load equipment.