On the Full Annular Rub in the Flexible Rotor — Compliant Stator System due to Friction

This paper describes a model of axisymmetric flexible rotor that slip-rolls a compliant isotropic stator. Three finite elements are used: rotating beam, rigid disk, and linear bearing. Friction in the system is considered as an aggregate of three components: contact friction, hysteretic and viscous damping. The stator is assumed to be fixed or mounted on elastic supports. Angular velocity and amplitude of rotor precession are determined by the matrix methods. It is shown that the angular velocity of the slip-roll depends on the coefficients of structural and contact friction. It is always lower than any given eigen frequency of the rotor leaning on the stator. The developed mathematical model corresponds to a large number of real rotor machines, for instance turbo- and oil-well pumps.

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