On Splitting of Bending Frequency Spectrum of Geometrically Imperfect Shells
The relevance of studying the deformation and strength is related to the use of thin circular cylindrical shells in structures exposed to intense dynamic operation. When studying complex dynamics issues, emphasis is made on solving the problems of free oscillations in structural elements. Real shell structures will unavoidably deviate from a perfect cylindrical shape (the initial imperfections) that emerge either in production or in operation. It is known that such imperfections result in specific phenomena as shells oscillate. Splitting of the bending frequency spectrum occurs not only when the number of shaping waves equals that of the shell–shape imperfection waves, as is believed nowadays, but also when the number of shaping waves is half that of the shell-imperfection waves. In the first case, the greater split eigen-frequency equals the frequency of perfect-shape shell oscillations, while the lower frequency is below that. The paper presents studies of how the initial deviations from a perfect circular shape affect the dynamic eigen-parameters of a thin circular cylindrical shell. It discovers the emergence of new splitting zones of the imperfect-shell bending frequency spectrum.
KeywordsOscillations Shells Imperfections
The research was financed by the grant of the Russian Science Foundation (project No. 18-79-00057).
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