Vibration analysis of a rotating closed section composite Timoshenko beam by using differential transform method

Document Type : Research Paper


1 Department of Mechanical Engineering, University of Isfahan

2 department of mechanical engineering, university of kashan, Kashan, Iran

3 Department of Mechanical Engineering, Faculty of Engineering, University of Isfahan, isfahan, iran


This study introduces the Differential Transform Method (DTM) in the analysis of the free vibration response of a rotating closed section composite, Timoshenko beam, which features material coupling between flapwise bending and torsional vibrations due to ply orientation. The governing differential equations of motion are derived using Hamilton’s principle and solved by applying DTM. The natural frequencies are calculated and the effects of the bending-torsion coupling, the slenderness ratio and several other parameters on the natural frequencies are investigated using the computer package, Mathematica. Wherever possible, comparisons are made with the studies in open literature.


Main Subjects

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