• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1997.04a
• /
• pp.91-100
• /
• 1997

In this paper the linearzed stiffness and damping coefficients of tilting pad thrust bearing are calculated by the perturbation method. The coefficients are obtained for a wide range of pivot positions. The effects of exciting frequency and pad mass on stiffness and damping coefficients are investigated. Critical frequencies due to the tilting motions of the pad are presented and are shown to be strongly influenced by the pivot position and pad mass.

• Tribology and Lubricants
• /
• v.13 no.2
• /
• pp.60-67
• /
• 1997

ER(electro-rheological) fluids, which are represented as Bingham fluids, have large and reversible changes in yield shear stresses by application of an electric field. In this paper, ER fluids are employed in a short squeeze film damper. The modified Reynolds equation for an ER short squeeze film damper is theoretically solved to get the approximate solutions of pressure profiles and damping coefficients. The theoretical approximate solutions are compared with numerical ones and both results are coincided very well. Both the direct and cross coupled damping coefficients substantially increase with increasing the yield shear stress of ER fluids. Furthermore, the synchronous response analysis of a rigid rotor supported on ER short squeeze film dampers is performed to show the improved damping capability of an ER short squeeze film damper.