Shock attenuation in lattices using phononics

Supersonic aircraft deal with turbulent conditions during flight. These turbulent conditions lead to unwanted stresses that often adversely affects the payload. Several lattices were designed to help attenuate any vibrations or shock that may be experienced by the payload through the concept of phononic crystals. Phononic crystals are periodic composite materials designed to control the propagation of mechanical waves using acoustic band gaps. Three different lattice deigns implemented to a cylindrical shell body were initially explored for this study. Combination lattices consisting of two different lattices within the same geometry were also explored. Combination lattices outperformed their single lattice design counterparts, in terms of frequency suppression, due to the fill factor of mechanically contrasting geometries. All lattice cases evaluated experienced a dominant peak in the frequency domain, near the ring frequency of the cylinder. Low frequency cantilevers were successful in trapping some of the energy caused by the ring mode of the structure.M.S.Includes bibliographical reference