Title

The Response of Rotating Machines on Viscoelastic Supports

Document Type

Conference Proceeding

Publication Date

9-19-2006

Publication Title

International Conference on Noise and Vibration Engineering

Abstract

Damping in the stator of a rotating machine is able to reduce the unbalance response, and increase the speed where the stability limit is reached. A convenient method to introduce damping is to support the bearings on viscoelastic elastomeric supports. This successfully adds damping but makes the analysis considerably more difficult. Viscoelastic materials have properties that depend on frequency and temperature. 55 Tuesday September 19, 2006 The determination of the run-up or run-down response of a linear machine at a constant temperature is quite straightforward based on measured material characteristics. However the introduction of transient and nonlinear effects, temperature changes and model uncertainties makes the analysis difficult. This paper uses the internal variable approach to model the viscoelastic material for the transient and non-linear dynamic responses. For balancing, robust estimation methods are demonstrated to provide satisfactory balancing of the machine over a range of environmental conditions. Examples of flexible machines on rolling element bearings supported on elastomeric mounts are given.