Nonlinear Dynamical Behaviors of a Cracked Turbocharger Rotor System with Base Excitation

摘要

A turbocharger rotor system supported on two lubrication bearings is approached by a two-disk discrete model. A transverse crack on the shaft is included and simulated by a breath-crack model. The nonlinear dynamical behavior of this cracked rotor-bearing system is investigated with considering the base excitation which is induced by engine vibration. A direct integration scheme is employed to approach the responses of the rotor system. Several factors such as rotary speed, crack depth and crack angle as well as eccentricity which may affect the system response and stability are studied respectively. Orbit, frequency spectrum, Poincare mapping and bifurcation diagram are used to study the nonlinear behaviors. The results are also compared with those which the base excitation is not considered. The predicted results indicate that the base excitation does contribution to constrain the quasi-periodic and chaotic motion of the studied rotor system.