Non Linear Dynamic Stability Analysis of Finite Flexible Oil Journal Bearings Including Fluid Inertia Effects

Non Linear Dynamic Stability Analysis of Finite Flexible Oil Journal Bearings Including Fluid Inertia Effects

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
  
© 2017 by IJETT Journal
Volume-49 Number-4
Year of Publication : 2017
Authors : K.C Ghosh, S.K.Mazumder, M.C.Majumdar
DOI :  10.14445/22315381/IJETT-V49P232

Citation 

K.C Ghosh, S.K.Mazumder, M.C.Majumdar "Non Linear Dynamic Stability Analysis of Finite Flexible Oil Journal Bearings Including Fluid Inertia Effects", International Journal of Engineering Trends and Technology (IJETT), V49(4),195-205 July 2017. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group

Abstract
The aim of this study is to analyse the Non-linear transient stability of finite oil journal bearing including the effect of fluid inertia and bearing liner surface deformations. The inertia effect is usually ignored in view of its negligible contribution compared to viscous force. However, fluid inertia effect is to be taken in the analysis when modified Reynolds number is around one. This investigation deals with the stability of finite isoviscous oil journal bearing with fluid film inertia effect using finite difference method. An attempt has been made to evaluate the critical mass parameter. A non-linear time transient method is used to simulate the journal centre trajectory to estimate the stability parameter, which is a function of speed. In the present work, a modified form of Reynolds equation is developed to include the combined influence of fluid inertia and bearing liner surface deformation for the analysis of finite isoviscous oil journal bearing. The modified average Reynolds equation considering inertia effect with bearing liner surface deformation is solved by a finite difference method with a successive over-relaxation scheme (Gauss-Siedel),while the equation of motion of the journal is solved by the fourth-order Runge-Kutta method. The stability increases with the increase of eccentricity ratio and modified Reynold’s numbers.

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Keywords
Modified Reynolds number, slenderness ratio, attitude angle, sommerfeld number, eccentricity ratio, journal bearings, inertia, and deformation factor.