Nonlinear vibrations of a misaligned bladed Jeffcott rotor

Abstract

This paper describes the numerical and experimental investigation of the nonlinear vibration of a bladed Jeffcott rotor. The nonlinearity in the system is due to discontinuities caused by multiple contacts with an outer ring as well as the nonlinear deformation of the massless blades. Contacts occur since the rotor shaft is initially misaligned by displacing the outer ring in one direction. The aim of the paper is to develop a simple model of bladed rotor and verify whether the global dynamics of the numerical simulations can be observed experimentally. The experimental rig and data acquisition are presented in detail together with the experimental procedures. The results between the numerical simulation and experiments are compared in terms of bifurcation diagrams and waterfall plots. An overall correlation is observed between the numerical and experimental study in the case of stiff blades, with differences mainly in localized frequency ranges due to parameter variation.