Design and development of one-dimensional acoustic bundle ventilated metamaterial

The recent emergence of acoustic metamaterials presents unparalleled possibilities for sound control across diverse scenarios. However, achieving both sound absorption and unrestricted airflow concurrently in a one-dimensional scenario poses a challenge. Most available acoustic metamaterials are designed in 2D or 3D, and in these configurations, a large portion of noise is reflected back. The key challenge, therefore, is how to allow maximum air to pass through the structure, make it tunable and noise be effectively damped within it. To address this, we propose four different types of configurations as KF (Kink Fiber), YAM (“Y” Type kink Fiber), CDAM (Converging Diverging Kink Fiber), and IRAM (Internal Resonator Kink Fiber, a unique one-dimensional design that simultaneously overcomes both challenges. The design subwavelength (7 cm) one-dimensional acoustic meta-structured blanket, demonstrating broadband sound absorption bandwidth of one octave with 0.5-0.9 absorption within the 500-1600 Hz range. In this study, we theoretically (through transfer matrix method), numerically (through FEM), and experimentally (through Impedance tube method) have showcased that this challenge can be surmounted by employing various configurations of kink fiber-based metamaterials. Following the concept developed in this article there have been efforts to develop blankets using hand lay-up method which can be deployed in real-world setup based on one-dimensional acoustic damping concept introduced in this work.