Document Type : Original Manuscript

Authors

Department of Naval Architecture and Marine Engineering, Faculty of Marine Engineering, Khorramshahr University of Marine Science and Technology, Khorramshahr, Iran.

Abstract

In this paper, free vibration of the ship with Timoshenko beam model is investigated and natural frequencies and mode shapes are obtained. Since the frequency equations of Timoshenko beam are nonlinear, for obtaining the frequencies and mode shapes, numerical method, differential quadrature method with discretization is used. Frequencies of some vessels with different geometers such as length, height and width are obtained and versus length, height and width are compared and effect of these parameters on the frequencies are investigated. These investigations show that by increasing these parameters the frequencies are decreased and for the vessels that have a large ratio of height to length, the Timoshenko beam model should be used for vibration investigation that the shear effect is considered.

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Main Subjects

Ale Ali, N. and Mohammadi, A.K., 2015. Effect of thermoelastic damping in nonlinear beam model of MEMS resonators by differential quadrature method. Journal of Applied and Computational Mechanics1(3), pp.112-121.
Amany, A. and Pasini, D., 2009. Material and shape selection for stiff beams under non-uniform flexure. Materials & Design30(4), pp.1110-1117.
Hagedorn, P. and DasGupta, A., 2007. Vibrations and waves in continuous mechanical systems. John Wiley & Sons.
Iijima, K., Yao, T. and Moan, T., 2008. Structural response of a ship in severe seas considering global hydroelastic vibrations. Marine structures21(4), pp.420-445.
Lin, T.R., Pan, J., O'Shea, P.J. and Mechefske, C.K., 2009. A study of vibration and vibration control of ship structures. Marine Structures22(4), pp.730-743.
Senjanović, I., Ćatipović, I. and Tomašević, S., 2007. Coupled flexural and torsional vibrations of ship-like girders. Thin-Walled Structures45(12), pp.1002-1021.
Zhu, S., Wu, M. and Moan, T., 2011. Experimental investigation of hull girder vibrations of a flexible backbone model in bending and torsion. Applied Ocean Research33(4), pp.252-274.