# Effect of Concentrated Axial Harmonic Force on Lateral Vibration of a Mono- Disk Rotating Shaft

Document Type : Research Article

Authors

1 Department of Mechanical Engineering, Yazd University, Yazd, Iran

2 Faculty of Mechanical Engineering, University of Yazd, Yazd, Iran

Abstract

Rotors are widely used in industry and studying their vibrations is important. Lateral vibration of the rotors during operation is more important than its other vibration modes such as axial and torsional. The aim of this paper is to determine the effects of loads axially exerted on the assembled disk on a rotor as an introduction to modeling common phenomena such as surge and chock in rotors. Therefore, in this paper, the effect of a concentrated axial force acted on disk on the lateral vibration of a jeffcott rotor is investigated. Also, the effect of unbalance force on vibration behavior of the rotor is studied. The equation of motion was derived from Timoshenko beam model. The set of governing equations for vibration analysis of the rotor consist of four coupled partial differential equations. Since the derived equations are complex and coupled, and they have time-varying coefficients, they are solved by a combination of Galerkin and Newmark methods. Numerical examples are analyzed. The accuracy of derived equations is verified for a simple beam. Results show that the axial load is considerably effective on the amplitude of the lateral vibration of the rotor.

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