Double local resonance effect acoustic metamaterial muffling performance

In order to effectively control low-frequency broadband noise, a dual local-domain resonance effect acoustic metamaterial based on Helmholtz resonator was proposed. The acoustic metamaterial was used to combine the Helmholtz resonance effect with the spring mass resonance effect, and control the deformation of the film by the driving voltage to realize the simultaneous change of the resonance frequencies of the two systems. On the basis of establishing the mathematical model of the system, the calculated natural frequency of the Helmholtz resonance system was 4141 Hz, the natural frequency of the flexible film system was 2868 Hz, and the theoretical deviation of the resonant frequency from the flexible film was 44%. The theoretical calculation deviation of the resonant frequency of the resonant cavity was 097%. The acoustic properties of acoustic metamaterials were studied using the acoustic-solid coupling physics of COMSOL software, and the acoustic metamaterials were tested using the dual load method. Results showed that the acoustic metamaterial had good noise control effect in the low frequency range, and generated two transmission loss peaks, forming a double local resonance effect, which can simultaneously control the noise in the two frequency ranges. When the driving voltage increased from 0 V to 350 V, the spring mass system transmission loss peak frequency was shifted from 30 Hz to 110 Hz, and the rate of change was 228%, which can realize adaptive control of noise and provide a method for active control and optimization of acoustic metamaterials.