Optimization of acoustic subwavelength slit barrier to control low-frequency noise in industrial buildings

Noise pollution in cities, mainly due to traffic and industry, is a pressing issue. This study explores acoustic barriers as a practical solution when direct noise reduction is unfeasible. We focus on optimizing slit-type acoustic barriers that use unique materials to block specific noise frequencies. These barriers are based on physical principles such as Wood’s anomaly, which allows the creation of barriers capable of selectively controlling sound. Employing Finite Element Method simulations, complemented by experimental measurements, we refine the barrier’s design to enhance performance in a targeted low-frequency range (100 to 300 Hz). By strategically rotating 6 pickets from the row pickets of the 24 pickets that make up the barrier, we achieve an optimized acoustic attenuation of 134% without modifying the barrier’s element count. This results in an effective sound attenuation design and is adaptable for industrial buildings and technical settings, as it permits heat and air to pass through while offering the flexibility of portable and tunable acoustic shading. Achieving proper acoustics comfort in industrial buildings would benefit workers by enhancing communication, facilitating task execution, and increasing productivity. Using sustainable Medium-Density Fiberboard from recycled fibers rather than other rigid materials is a key design feature that promotes environmental conservation and supports sustainable practices. This research makes a notable advance in noise control engineering, introducing a flexible and effective way to design noise barriers for environmental and engineering applications needing targeted noise reduction. Finally, additional optimizations were performed for three further frequency ranges to enhance the versatility of the proposed design. • A technologically advanced subwavelength acoustic barrier is proposed. • Optimized design of acoustic attenuation barriers in industrial buildings. • The presented model allows the selection of the industrial noise attenuation band.