A Comparative Linear and Nonlinear Stability Analysis of Hybrid Journal Bearing Operating with Micropolar Lubricant

Abstract

The present study discusses the effect of micropolar parameters on the stability of symmetric hole-entry hybrid journal bearing system compensated with capillary restrictor. Finite element method has been used to solve the modified Reynolds equation for the flow of micropolar lubricant through the bearing. The linearized and nonlinear equations of motion are solved numerically using fourth order Runge-Kutta Method at each integration time step. Solution of these equations provides the locus of moving journal center and the journal trajectories are plotted with the help of a computer program. A Routh-Hurwitz stability criterion has been applied to calculate the critical mass of the journal to analyze the stability of journal. A comparative analysis for linear and nonlinear models considering Newtonian and micropolar lubricants has been done. The results obtained indicate that micropolar parameters affect the performance as well as the stability margin of the hybrid journal bearing system considerably and nonlinear analysis provides quick response as compared to linear one.

Analysis of misaligned hydrodynamic porous journal bearings in the steady-state condition with micropolar lubricant

“…19,24 In case of nuclear power generation, sodium, performing a dual role of heat transfer and lubrication also exhibited non-Newtonian characteristics 24 and micropolar theory may be used in the analysis. Several other researchers [25][26][27][28][29][30][31][32][33][34] worked on plain journal bearing with micropolar fluid and explained the advantageous effect of micropolar fluid over conventional Newtonian fluid. Das et al 35 presented a theoretical analysis on the micropolar plain journal bearing with misalignment and concluded that the misalignment effect on micropolar lubrication improves the load-carrying ability and other properties of a self-acting bearing.…”

A Study on the Influence of Combined Elastic and Micropolar Effects on Hole-Entry Hybrid Journal Bearing

“…Also, Bansal et al [22] highlighted elastic distortion effects on stability of micropolar lubricated hydrodynamic bearing and their results indicated that increase in flexibility causes decrease in stability. Various studies concerning the theory of micropolar lubricant and effects of micropolar parameters on performance and stability of journal bearings have also been reported in literature [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39].…”