Influence of axial thrust bearing defects on the dynamic behavior of an elastic shaft

In this work, the non-linear dynamic behavior of a flexible shaft is presen ted. The shaft is mounted in two journal bearings and axial load is support ed by a hydrodynamic thrust bearing, at one end. The coupling between the a xial thrust bearing behavior and the bending vibrations of the shaft is esp ecially studied. The shaft is modeled by a typical beam finite element meth od and includes gyroscopic effects. The dynamic behavior of the journal bea rings and the thrust bearing are considered to be non-linear. The dynamic b ehavior is analyzed with a transient time integration procedure. The thrust bearing provides additional stiffness and additional damping on the flexib le shaft. A defect on the thrust bearing rotor excites a critical speed. (C ) 2000 Elsevier Science Ltd. All rights reserved.