Optimal Design of Acoustic Ventilated Metasurfaces Using Enhanced Whale Optimization Algorithm

Abstract

To address the problem of construction site noise interference while accommodating ventilation needs within confined spaces of urban buildings, this paper proposes a joint simulation approach utilizing the finite element method and an enhanced whale optimization algorithm (EWOA). This method systematically analyzes how the structural dimensions of ventilated acoustic metamaterials (VAM) sub-cavities and the shapes of central through-holes affect acoustic performance. By implementing a step-by-step optimization strategy, we systematically investigated the effects on acoustic performance, leading to the successful development of exceptionally ventilated ultra-thin acoustic metamaterials (EVUAM) that excels in both ventilation and sound insulation. The sub-cavity structure was first optimized and designed, and subsequently, the shape of the central through-hole was further optimized to balance the ventilation and acoustic insulation effects while maintaining the results of the optimization of the sub-cavity structure. The EVUAM achieved a broadband noise insulation effect of at least 6 dB in the frequency range from 500 to 2000 Hz, features a compact structure with a thickness of just 60 mm, and shows a 67% increase in ventilation capacity compared with that of the original VAM. Based on EVUAM, a novel acoustic barrier structure was developed through numerical simulation, achieving a noise attenuation performance exceeding 10 dB in specific frequency bands, which demonstrates an improvement of over 4 dB compared to conventional engineering benchmarks. Experimental validation demonstrates strong agreement between physical prototypes and simulations at critical frequency points. Detailed simulation and experimental verification support the effectiveness of the joint simulation methodology and step-by-step optimization strategy as well as the excellent performance of EVUAM in real-world applications. This new design not only enhances air ventilation but also improves noise insulation as much as possible, addressing the need for healthy and comfortable indoor environments in urban buildings, and providing valuable engineering insights for low-frequency broadband noise reduction technology.