%0 Journal Article %T STABILITY ANALYSIS OF THREE LOBE HYDRODYNAMIC JOURNAL BEARING: COUPLE STRESS FLUID EFFECTS %A N.P.Mehta %A S.S.Rattan %A Rajiv Verma %J International Journal of Engineering Science and Technology %D 2010 %I Engg Journals Publication %X The effects of couple stress fluid, when added to a Newtonian base, are studied by deriving a generalized form of the Reynolds equation. A couple stress parameter ¡®l¡¯ has been used to indicate the length of the long chain molecule being added. Finite element method has been used to solve the generalized Reynolds equation for each lobe to obtain the respective pressure distributions. Stable equilibrium conditions in terms of eccentricity ratios and the attitude angles have been obtained for the vertical load condition. The journal has been perturbed from this equilibrium condition to give the stiffness and the damping coefficients. It has been observed that slight variation of the coupe stress parameter ¡®l¡¯ has great influence on the dynamic characteristics, i.e. the stiffness and the dampingcoefficients. The threshold speed and the critical mass of the journal, obtained as a solution to the linearized equations of motion, are used to demonstrate the increased stability of the journal bearing system. %K journal bearing %K couple stress fluid %K dynamic analysis %K stability %U http://www.ijest.info/docs/IJEST10-02-10-010.pdf