Soft resonator of omnidirectional resonance for acoustic metamaterials with a negative bulk modulus.

ABSTRACT: Monopolar resonance is of fundamental importance in the acoustic field. Here, we present the realization of a monopolar resonance that goes beyond the concept of Helmholtz resonators. The balloon-like soft resonator (SR) oscillates omnidirectionally and radiates from all parts of its spherical surface, eliminating the need for a hard wall for the cavity and baffle effects. For airborne sound, such a low-modulus resonator can be made extremely lightweight. Deep subwavelength resonance is achieved when the SR is tuned by adjusting the shell thickness, benefiting from the large density contrast between the shell material and the encapsulated gas. The SR resonates with near-perfect monopole symmetry, as demonstrated by the theoretical and experimental results, which are in excellent agreement.

SUBMITTER: Jing X 

PROVIDER: S-EPMC4633608 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature