Sound absorption of microperforated panel with L shape division cavity structure

Microperforated panel (MPP) absorbers have been widely used in noise reduction and are regarded as a promising alternative to the traditional porous materials. However, the absorption bandwidth of a single-layer MPP with limited cavity space is insufficient to compete with the porous materials. In order to improve the sound absorption ability of the single-layer MPP with limited cavity space, MPP with L shape division cavity structure is introduced. Based on the MPP and electro-acoustical equivalent circuit principle, sound absorption properties of MPP with L shape division cavity are studied. Simulation and experimental results show that MPP with L shape division structure have better sound absorption performance than MPP with single cavity structure. Building on L shape division cavity, the extended plate can further improve the sound absorption of MPP. Wide band sound absorption of MPP can be realized with limited cavity space.