Acoustic properties analysis of ABH complex structures with micro-perforated boundaries

In this paper, a composite structure with a micro-perforated boundary acoustic black hole is designed to control low-frequency band and wide-band noise. Firstly, the finite element and transfer matrix theoretical models for calculating the sound absorption coefficient of this system are respectively established and compared to verify. In addition, the acoustic properties inside the composite structure and the acoustic black hole effect of the composite structure were investigated at different frequencies. Secondly, this paper investigates the effects of the different parameters of composite structures on their sound absorption performance. Furthermore, the parameters of the composite structure are optimized using the Nelder-Mead simplex method. After optimization, the sound absorption coefficient of the composite structure is consistently above 0.9 from 325 Hz (735 Hz before optimization). Finally, the experimental results validate the accuracy of the finite element and transfer matrix methods. The optimized composite structure with microperforated boundary acoustic black holes has excellent sound absorption performance, which provides a new solution for efficient low-frequency broadband noise control in small-volume structures.