Ultralow-frequency tunable acoustic metamaterials through tuning gauge pressure and gas temperature

Acoustic metamaterials possessing subwavelength characteristics can be used for low-frequency noise and vibration control. with adjustable dynamic properties further enhance their possible applications. This paper designs a kind of tunable acoustic consisting the frame structure, airbag, balancing weight. And manipulated by tuning gauge pressure gas temperature in airbag. The calculation results indicate that effectively suppress wave propagation ultralow-frequency band gap (about 13Hz∼90Hz) during manipulation. complete is overlapping frequency range an out-of- in-plane gaps. Numerical analyses formation out-of-plane due to coupling between resonant mode weight anti-symmetric Lamb structure. In contrast, symmetric Meanwhile, manipulation mechanism these gaps stems from fact through or temperature, structural stiffness airbag (torsional stiffness, in-plane, stiffness) structure (in-plane bending significantly tuned so modes related them manipulated. active control noise. It provide guidelines designing other