Performance Analysis of a Conical Hydrodynamic Journal Bearing

Many turbo-machines such as turbines and compressors generate axial and radial load during their operation. Conical hydrodynamic journal bearing is proposed to sustain radial load and adjust the effect of axial load on rotating elements. The present study has proposed the performance analysis for conical hydrodynamic journal bearing of semi-cone angles (γ = 5°, 10°, 20°, 30°) for a wide range of radial load (W¯r=0.1-0.9\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\bar{W}_{\text{r}} = 0.1 - 0.9$$\end{document}) on rotating journal. Finite element method has been used to solve the modified Reynolds equation for investigating the flow of lubricant in the clearance space between journal and bearing. Performance characteristics such as load-carrying capacity, fluid film thickness, stiffness coefficients, damping coefficients and threshold speed for various configurations of conical hydrodynamic journal bearing have been presented and discussed. Results show that threshold speed (ω¯th\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\bar{\omega }_{\text{th}}$$\end{document}) of conical journal bearing is considerably reduced as the semi-cone angle increases to γ = 30° as compared to the base bearing of semi-cone angle γ = 5°.