Development and validation of efficient rotordynamical models for complex rotating systems

Abstract

A correct prediction of the dynamic behaviour of rotors represents a critical issue in the rotating machines field. A large amount of research work dealing with rotor-dynamics modelling can be found in literature and nowadays both traditional simple and complex models may be adopted to investigate the vibration behaviour of rotating equipments. In this paper, the authors introduce an accurate and general-purpose model for the evaluation of the dynamic behaviour of multi-rotor systems, that has been conceived with the purpose of modelling complex rotors through a systematic and practical approach. The model, which aims at overcoming the modelling limitations characterising commercial dedicated softwares and which is based on a finite element rotor-dynamics formulation, is able to deal with long rotors characterised by complex topology, such as rotor with distributed inertias or connected simultaneously in several points. The investigated rotor test case is a flywheel masses test bench for railway brakes that is formed of several rotors with complex topology (distributed inertias). The model has been validated in a preliminary step by means of experimental data coming from a test campaign for the vibration assessment, performed in collaboration with Politecnico di Milano.