Porous materials are widely employed as sound absorbers across various industries due to their effectiveness in mitigating noise, particularly in the mid-to-high frequency range. However, their performance in low-frequency sound absorption remains limited. This limitation is due to the dependence of sound absorption in porous layers of finite thickness on the relationship between wavelength and thickness, where absorption peaks occur at frequencies determined by quarter-wavelength resonances. In this talk, I will present my past and ongoing research aimed at enhancing sound absorption by tuning these quarter-wavelength resonances. First, I will briefly introduce metaporous layers engineered to modify the effective wave propagation length and sound velocity within porous layers. I will then discuss optimizing the porosity distribution of 3D-printed porous lattice structures. The effects of geometric parameters on sound absorption in these lattice structures will be explored, followed by the presentation of an optimized porosity distribution for enhanced performance.
Dr. Jieun Yang is an Assistant Professor in the Faculty of Mechanical Engineering at Delft University of Technology (TU Delft). Her research focuses on the design of acoustic metamaterials for reducing unwanted sound and vibrations. She earned both her bachelor’s and PhD degrees in Mechanical Engineering from Seoul National University, South Korea, in 2010 and 2016, respectively. Before joining TU Delft, she worked at Samsung Electronics (2016–2018) and Eindhoven University of Technology (2019–2022).
Posted on 30th September 2024 in Events
