Whirling Analysis of Axial-Loaded Multi-Step Timoshenko Rotor Carrying Concentrated Masses

Subject Areas : Engineering

K Torabi ¹ (Faculty of Mechanical Engineering, University of Isfahan, Isfahan, Iran)
H Afshari ² (Faculty of Mechanical Engineering, University of Kashan, Kashan, Iran)
H Najafi ³ (Department of Solid Mechanics, Faculty of Mechanical Engineering, Politecnico di Milano, Milan, Italy)

Received: 2016-11-12 Accepted : 2017-01-14 Published : 2017-03-30

Keywords: Axial load, Concentrated mass, Whirling analysis, Timoshenko rotor, Multi-step, Rotational inertia, Transfer matrix method (TMM),

Abstract :

In this paper, exact solution for two-plane transverse vibration analysis of axial-loaded multi-step Timoshenko rotor carrying concentrated masses is presented. Each attached element is considered to have both translational and rotational inertia. Forward and backward frequencies and corresponding modes are obtained using transfer matrix method (TMM). The effect of the angular velocity of spin, value of the translational and rotational inertia, position of the attached elements and applied axial force on the natural frequencies are investigated for various boundary conditions.

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