Study on Sound Absorption Characteristics of Multi-Cavity Micro-Perforated Panel

• Main Authors: Hu, Wen-Hsin, 胡文信
• Other Authors: Shyu, Rong-Juin
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/fkc88f

碩士 === 國立臺灣海洋大學 === 系統工程暨造船學系 === 106 === The theory of Maa’s is based on a perforated plate less than 1 mm. The sound absorption and characteristics of micro-perforated panel are calculated by using the hole diameter, panel thickness, perforation ratio, and thickness of the back cavity. This paper uses finite element method to simulate the micro-perforated panel, In order to improve the application of micro-perforated panel, a single cavity thickness simulation was carried out through establish models with cavity thicknesses of 10 mm, 29 mm, 71 mm, and 154 mm, which were verified with Maa’s theory, and then discussed the sound absorption performance with different cavity angles. And the four cavity thickness of the two-cavity and four-cavity simulation and compare with the Iman Falsafi and Abdolreza Ohadi theory, and then in the end use no partition of the double, four cavity to explore its sound absorption performance. Model establishment is reference ASTM E1050-98 set specifications, after meshing, and then simulated by the finite element software. The micro-perforated panel setup is based on the Maa’s theory to import parameters to calculate the acoustic impedance. For ordinary perforated panel, Lee and Zhan used Mechel function to calculate the acoustic impedance and used the transfer admittance method to calculate the transmission loss of the muffler. This paper used this method to set the acoustic impedance of the micro-perforated panel by the transfer admittance method. Solve the problem of meshing caused by holes in the micro-perforated panel. Finally, use the transfer function to calculate the sound absorption coefficient and compare them. The simulation results show that the use of this method for micro-perforated panel simulation is in good agreement with Maa’s theory, confirming the feasibility of this simulation method. In the cavity simulation with varying angles, the cavity volume is also positively correlated with the sound absorption coefficient, multi-cavity. The simulation is in good agreement with the theory of Iman Falsafi and Abdolreza Ohadi.