Affiliations: School of Aerospace Engineering, Georgia Institute of
Technology, Atlanta, GA 30332, USA
Note: [] Corresponding author: Massimo Ruzzene, School of Aerospace
Engineering, Georgia Institute of Technology, 270 Ferst Drive, Atlanta GA,
30332-0150, USA. Tel.: +1 404 894 3078; Fax: +1 404 894 2760; E-mail:
[email protected]
Abstract: The wave propagation in and the vibration of cylindrical grid
structures are analyzed. The grids are composed of a sequence of identical
elementary cells repeating along the axial and the circumferential direction to
form a two-dimensional periodic structure. Two-dimensional periodic structures
are characterized by wave propagation patterns that are strongly frequency
dependent and highly directional. Their wave propagation characteristics are
determined through the analysis of the dynamic properties of the unit cell.
Each cell here is modelled as an assembly of curved beam elements, formulated
according to a mixed interpolation method. The combined application of this
Finite Element formulation and the theory of two-dimensional periodic
structures is used to generate the phase constant surfaces, which define, for
the considered cell lay-out, the directions of wave propagation at assigned
frequencies. In particular, the directions and frequencies corresponding to
wave attenuation are evaluated for cells of different size and geometry, in
order to identify topologies with attractive wave attenuation and vibration
confinement characteristics. The predictions from the analysis of the phase
constant surfaces are verified by estimating the forced harmonic response of
complete cylindrical grids, obtained through the assembly of the unit cells.
The considered analysis provides invaluable guidelines for the investigation of
the dynamic properties and for the design of grid stiffened cylindrical shells
with unique vibration confinement characteristics.
