Micropolar Fluids Effects on the Dynamic Characteristics of Four-lobe Journal Bearing

Dynamic characteristics of a four-lobe journal bearing of micropolar fluids are presented. Lubricating oil containing additives and contaminants is modelled as micropolar fluid. The modified Reynolds equation is obtained using the micropolar lubrication theory and solving it by using finite difference technique. The dynamic characteristics in terms of stiffness, damping coefficients, the critical mass and whirl ratio are determined for various values of size of material characteristic length and the coupling number. The results show compared with Newtonian fluids, that micropolar fluid exhibits better stability.

Authors:

• B. Chetti

Keywords:

• Four-lobe bearings
• dynamic characteristics
• stabilityanalysis
• micropolar fluid

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