Dynamics of Anisotropically Supported Rotors

[摘要] The paper discusses dynamic effects occurring in machinery rotors supported in bearings andpedestals with laterally different characteristics. In the considered rotor model the anisotropyof radial stiffness and tangential (“cross”) stiffness components are included. Within certainranges of the rotative speed the support anisotropy leads to the specific, excited-by-unbalancerotor lateral synchronous vibrations in a form of backward (reverse) precession. Inaddition, one section of the rotor may precess backward, while the other section simultaneouslyprecesses forward. Experimental results illustrate this phenomenon. The analyticalmodel of the system is based on multimode modal approach. It is also shown in this paperthat greatly enhanced information for machine malfunction diagnostics can be obtained bysimulated rotation of the XY transducer system observing rotor lateral vibration. This simulatedrotation can be accomplished by the machine diagnostic data acquistion and processingsystem. The data processing also includes extraction of forward and backward componentsof elliptical orbits filtered to one frequency, and the filtered orbit major axis magnitude andits angular orientation.Numerical examples, field data, and experimental results performed on a rotor rig illustrateapplications.

[学科分类] 力学，机械学