Effects of the Wet Steam Non-Equilibrium Condensation on the Dynamics of the Excitation-Relying Bearing-Rotor system

Abstract

This paper investigated the effects of the wet steam non-equilibrium condensation on the dynamic characteristics of the bearing as well as the bearing-rotor system by constructing and analyzing a non-linear coupled model of the bearing-rotor system. An excitation-relying dynamic model of bearing is established based on the finite difference method, in which the excitation is converted from the pressure pulsation on the surface of rotor blades generated from the non-equilibrium condensation process. The Raccia transfer matrix method is implemented to analyse the dynamic behavior of this coupled system. Results show that the wet steam non-equilibrium condensation process would greatly reduce the bearing stiffness and damping and result in more intense vibration of the system, besides, its induced pulsed displacement would drive the excitation-relying bearing-rotor system more unstable.