Sound Reduction Control in Acoustic Enclosure with Air Ventilation

An acoustic enclosure system with both interior sound reduction and air ventilation is designed and demonstrated. The system consists of a rectangular enclosed space coupled with ventilated metamaterials and microperforated panels (MPPs). By modeling the ventilated metamaterial as an impedance boundary condition, an analytic model is developed to characterize the frequency response of interior acoustic fields and evaluate the sound reduction performance of MPP structures. Numerical simulations are conducted to validate the accuracy of the theoretical model. It is found that the resonance response of the enclosure system can be suppressed by proper arrangement of the MPPs. Even with open area for airflow, the system still possesses good sound isolation originating from the low-transmission behavior of the ventilated metamaterial. The proposed model system may find potential applications in noise control engineering.