Low- and mid-frequency noise is prevalent in civil engineering, industrial equipment, and military environments. Due to its long wavelength, strong penetration capability, and slow attenuation, such noise is particularly difficult to control and may adversely affect equipment reliability and human health. To address the limited low-frequency absorption efficiency, narrow effective bandwidth, and excessive thickness of conventional porous materials, this presentation focuses on aluminum-foam sound-absorbing materials and low-frequency broadband coupled acoustic metamaterials. It systematically introduces pore-structure regulation in aluminum foam and the resulting acoustic absorption characteristics, with particular emphasis on the coupling mechanisms among space-coiling structures, porous materials, and microperforated panels, as well as strategies for achieving broadband absorption. Building on the research group’s recent progress, the presentation will also briefly introduce design concepts for novel coupled sound-absorbing structures and explore the potential of machine learning for performance prediction, parameter optimization, and computer-aided design in complex parameter spaces. The work is intended to provide guidance for the engineering design of lightweight, thin, low-frequency broadband sound-absorbing structures.

Yonghua Wang is a Professor and Ph.D. Supervisor at Changchun University of Science and Technology. She received her Ph.D. through a joint doctoral training program with École Centrale de Lyon, France, and was selected for the Jilin Province "Changbai Talent Program." She serves as a Young Editorial Board Member of Advanced Bionics and Journal of Bionic Engineering.

Her research focuses on sound absorption and noise reduction, electromagnetic wave-absorbing metamaterials, drag reduction and heat dissipation, and the fabrication of bio-inspired functional surfaces. She has served as principal investigator for nine national and provincial research projects, including the National Natural Science Foundation of China (General and Young Scientists Fund) and key R&D projects funded by the Jilin Provincial Department of Science and Technology. She has also participated in more than 30 national and provincial research projects, including the National Key Research and Development Program of China and major provincial initiatives. She received the Second Prize of the Jilin Provincial Science and Technology Progress Award. To date, she has published more than 20 SCI-indexed papers, authored one academic monograph, and served as chief editor of two textbooks.