Free vibration frequencies of prismatic thin shells

Abstract

The paper examines the natural frequencies of prismatic thin shells, the cross-section of which is the regular polygon. Spectra of free vibration frequencies of such shells are analyzed as the number of cross-section sides increases, provided that the perimeter is preserved. The relation between fundamental frequencies of the prismatic shells with the regular polygonal cross-section and a circular cylindrical shell is discussed. For a small and large number of polygon sides analytical and asymptotic solutions are compared with numerical solutions obtained by the finite element method (COMSOL). The convergence of the numerical method is studied for the prismatic shell with a large number of facets.

Keywords

• free vibrations of thin shells
• prismatic shells
• finite element method