Experimental and numerical evidence of comparable levels of attenuation in periodic and a-periodic metastructures

Abstract

“Phononic Crystals” are designed on the basis of a single cell periodically repeated in space along one or more directions. However, this may result as restrictive in terms of possible optimal solutions found. The present paper shows, numerically and experimentally, that it is possible to have high levels of attenuation also with a-periodic metastructures. Comparing two “phononic metastructures” externally identical but internally different, it is demonstrated that perturbing the periodicity inside the structure does not significantly affect its attenuation capabilities. This opens new possibilities in the field.