Multi-physical Analysis of the Forces in the Flexible Rotor Supported by the Magnetorheological Squeeze Film Dampers

Abstract

To reduce lateral vibrations of rotating machines, the damping devices are placed between the rotor and its frame. This is enabled by magnetorheological squeeze film dampers. To achieve their optimum performance their damping effect must be adaptable to the current working conditions. In this paper, modelling of the magnetorheological squeeze film damper is based on the assumptions of the classical theory of lubrication except that for the lubricant. The model is completed with the magnetic force acting between the damper rings. Therefore, the magnetostatic approaches to determining the magnetic field in the damper gap at different distinguishing levels were proposed and compared. The developed mathematical model was applied for analysis of a rotating machine with a flexible shaft. The carried out computational simulations confirmed that the developed magnetorheological damper arrives at significant suppression of the rotor vibration in a wide range of running speeds.