The Vibration Isolating Properties of Uncentralized Squeeze-Film Damper Bearings Supporting a Flexible Rotor

Abstract

The ability of an uncentralized squeeze-film damper bearing to inhibit the effects of vibration in a flexible rotor-bearing system, has been assessed in terms of non-dimensional system parameters. This analytical approach has shown that a correctly designed squeeze-film damper bearing is a very effective means of reducing both the amplitude of motion of the rotor and the force transmitted to the bearing support structure. However, the analysis has also indicated that a poorly designed squeeze-film damper bearing can produce amplitudes and forces greater than those which would arise if the bearing support remained rigid. An experimental programme has supported the validity of the above analytical technique by showing that the measured motion orbits of the journal and disk centers as the rotor passes through the critical speed, are very similar to those predicted theoretically. Also, the response curves for specific groups of system parameters show very similar trends in practice, to those which result from the analytical approach. Some indication of the ability of a squeeze-film damper bearing to reduce the effect of much greater unbalance than normal is also reported.