Thermohydrostatic analysis of capillary compensated symmetric hole-entry hybrid journal bearing operating with non-Newtonian lubricant

摘要

Purpose - Every high speed machine, demanding high level of perfection, can operate successfully through a precise design of bearings. Such a design can be formulated after carefully studying both static and dynamic characteristics of the journal bearing. The present paper aims to describe the study of static and dynamic performance of a hole-entry hybrid journal bearing system compensated with capillary restrictor by considering the combined influence of thermal effects and non-Newtonian behavior of the lubricant. Design/methodology/approach - The variation of the viscosity due to the non-Newtonian behavior of the lubricant and temperature rise is considered in the study. The numerical solution of the generalized Reynold's, equation governing the flow of the lubricant having variable viscosity along with the energy and heat conduction equations is obtained using finite element method. The non-Newtonian lubricant has been assumed to follow the cubic shear stress law. The study includes performance of a double row symmetric hole entry hybrid journal bearing configuration containing 12 holes per row. Findings - The results indicate that change in viscosity of lubricant affects the bearing design parameters. Originality/value - The paper shows that accurate theoretical modeling of the bearing is an effective tool for the selection of design parameter such as bearing land width ratio ({partial deriv}{top}-){sub}b, restrictor design parameter (C{top}-){sub}(s2), and non-linearity factor K{top}-.