Lightweight asymmetric thin film metamaterial for low frequency sound isolation

Abstract

The application relates to a low-frequency sound insulation and noise reduction technology, in particular to a light-weight asymmetric film metamaterial for low-frequency sound insulation, which comprises a film, asymmetric annular masses acting as acoustic metamaterial masses and pasted on the same side surface of the film, and frames pasted on the two side surfaces of the film; wherein four same asymmetric annular masses are symmetrically distributed in a cross shape on the same side surface of the film, the directions are consistent, and the film is tightly pasted between two same frames; the above structure constitutes a cell of the acoustic metamaterial, and the acoustic metamaterial is formed by uniformly and closely periodically arranging the cells in the horizontal and vertical directions on a plane. The structure generates a reverse resonance mode through the local resonance characteristics of the whole system of the film and the mass, and generates a new asymmetric reverse resonance mode through the structure of the asymmetric mass, so that the sound insulation peaks increase, the effective sound insulation frequency band can be widened, and the position and density of the sound insulation peaks can be effectively adjusted by changing the size parameters of the mass and the film to meet different working scene requirements.