Dual-functional broadband sound absorption and silencing via interference resonance coupling

Abstract

The integrated design of multifunctional acoustic structures provides a cost-effective strategy for low-frequency and broadband noise control, particularly in space-constrained environments. In this Letter, a dual-functional noise control structure based on a hybrid mechanism that combines interference and resonance effects is proposed. The dual functionality is achieved through a symmetric interference–resonance coupling structure, whose identical inlet and outlet ports enable versatile implementation. The structure functions both as an efficient sound absorber that suppresses reflected sound in indoor environments and as a compact silencer that attenuates transmitted sound in duct systems. An adaptive particle swarm optimization algorithm with enhanced sample diversity is employed to optimize the geometric parameters. The optimized structure exhibits an average absorption coefficient exceeding 0.8 within the 700–1700 Hz range and an average transmission loss of 10 dB under grazing incidence. Excellent agreement among theoretical analysis, finite element simulations, and experimental measurements confirms the effectiveness of the proposed design. Owing to the interference–resonance coupling mechanism and the dual functionality, the proposed structure is well suited for broadband noise control at low to mid frequencies.