Vibration characteristics of rotor system with tilting-pad journal bearing of elastic and damped pivots

Abstract

In view of an entire dynamic model of tilting-pad journal bearing (TPJB) in which the pads swing and vibrate along geometric direction of preload, a TPJB of elastic and damped pivots was designed and manufactured. Vibration experiments were carried out under the conditions of different rotor bending stiffness and oil supply pressure to find out the relationship between the new bearing’s vibration depression effect and other dynamic parameters of the rotor. The result shows that critical amplitudes can be efficaciously reduced while system’s stability can be remarkably improved by this bearing. Besides, the bearing’s effect of vibration depression weakens as the rotor bending stiffness increases, but heightens it as the oil supply pressure increases.

Keywords

tilting-pad journal bearing of elastic and damped pivots / elastic shims / damping / stiffness / oil supply pressure

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