Affiliations: School of Naval Architecture and Ocean Engineering,
Huazhong University of Science and Technology, Wuhan, Hubei, China
Note: [] Corresponding author: Jianhui Wei, School of Naval Architecture
and Ocean Engineering, Huazhong University of Science and Technology, Wuhan
430074, Hubei, China. Tel.: +86 139 9566 4256; Fax: +86 0278 754 2416; E-mail:
[email protected]
Abstract: Wave based method which can be recognized as a semi-analytical and
semi-numerical method is presented to analyze the free vibration
characteristics of ring stiffened cylindrical shell with intermediate large
frame ribs for arbitrary boundary conditions. According to the structure type
and the positions of discontinuities, the model is divided into different
substructures whose vibration field is expanded by wave functions which are
exactly analytical solutions to the governing equations of the motions of
corresponding structure type. Boundary conditions and continuity equations
between different substructures are used to form the final matrix to be solved.
Natural frequencies and vibration mode shapes are calculated by wave based
method and the results show good agreement with finite element method for
clamped-clamped, shear diaphragm – shear diaphragm and free-free boundary
conditions. Free vibration characteristics of ring stiffened cylindrical shells
with intermediate large frame ribs are compared with those with bulkheads and
those with all ordinary ribs. Effects of the size, the number and the
distribution of intermediate large frame rib are investigated. The frame rib
which is large enough is playing a role as bulkhead, which can be considered
imposing simply supported and clamped constraints at one end of the cabin and
dividing the cylindrical shell into several cabins vibrating separately at
their own natural frequencies.
Keywords: Wave based method, semi-analytical and semi-numerical method, cylindrical shell with intermediate large frame ribs, free vibration analysis
