Flexural vibration of rotating shafts by frequency domain hybrid modelling

In this paper the flexural vibration of a cantilevered rotating marine prop eller is considered. From the transfer matrices of the distributed shaft an d the lumped disc model, characteristic determinant of the distributed-lump ed model of the system is derived. Direct search optimisation techniques ar e employed, enabling complex roots of the irrational characteristic determi nant to be determined. Frequency response methods are used to determine the flexural response of the system. The discrete inverse Fourier transform te chnique is employed to compute the transient response from the frequency re sponse data. Both the resonance and gyroscopic effects are identified. It i s shown that by using frequency domain hybrid techniques, the system could be represented accurately by a reduced order model. (C) 2000 Elsevier Scien ce Ltd. All rights reserved.