In order to control the wide-band noise

An acoustic metamaterial with both Helmholtz resonance and spring mass system resonance and its control method were proposed.. The double local resonance system was equivalent to the series connection of two spring mass systems. Theoretical results showed that two local resonance band gaps can be generated in the double resonance acoustic metamaterials. The correctness of the mathematical model was verified by the Finite Element Method. Based on the comparison of the influences of resonant volume and membrane tension on the transmission loss of the system

the pneumatic modulation was selected to control the tension of the membrane and then the transmission loss. The measurement indicated that

when the driving air pressure increased from 0 to 2 kPa

the first transmission loss peak of the system kept almost constant while the second transmission loss peak shifted 150 Hz to the high frequency. The designed local resonance acoustic metamaterials have good control effect on low-frequency noise in the band gap range

thus providing a method for adaptive control of broadband noise.