Borysiuk O. Self-sustained vibrations of horizontal rotors in cylindrical journal bearings

The research subject are self-sustained vibrations, forced vibrations, bifurcations and stability of periodic and semi periodic vibrations of horizontal flexible rotors in cylindrical arbitrary length bearings. The dissertation objective is development of methods for analysis of self-sustained vibration of elastic horizontal rotors in the cylindrical arbitrary length journal bearings and investigation of the stability and bifurcations of periodic and almost periodic self-sustained vibrations of rotor systems. The research methods are harmonic balance method, shooting technique, nonlinear normal modes and continuation technique. Method for nonlinear arbitrary length journal bearing forces analysis is created. An approach for analysis of rotors vibrations based on the method is proposed. Scientific novelty are consists in development of numerically-analytical method for estimation of fluid film forces of arbitrary length cylindrical journal bearings for analysis of self-sustained vibrations of rotor, analysis of self-sustained rotor vibrations with significant amplitudes at significant perturbations of the initial state of the system, analysis of journal bearings parameter influence on self-sustained vibration amplitudes. Method for estimation of fluid film forces of arbitrary length cylindrical journal bearings was used by state enterprise plant "Electrotyazhmash" and National Technical University "KhPI". Application branch is organizations which carried out the design and manufacture of rotor equipment.