空心管型泡沫铝吸声性能的数值模拟分析OA北大核心CSTPCD

In order to improve the sound absorption performance of porous aluminum foam,the aluminum foam was processed to form a hollow tube structure.The acoustic impedance tube test system was used to obtain the sound absorption coefficient.Based on the JCA acoustic model,COMSOL was used to simulate the hollow tube aluminum foam to obtain the sound absorption coefficient.The reliability of the simulation model was verified by comparing the simulation results with the experimental results.The internal sound field of the hollow tube aluminum foam was analyzed by the sound pressure filed and the dissipated power density,and the influence of hollow tube parameters on sound absorption performance was further explored by numerical simulation.The results show that the structure belongs to resonant sound absorption structure.When the frequency of sound wave is the same as the natural frequency of the structure,the amplitude of the vibration of the structure excited by sound wave is the largest,which will cause a lot of sound energy consumption and play the role of sound absorption.For the hollow tube aluminum foam structure,the sound absorption coefficient can be improved by increasing the radius of the hollow tube and the number of hollow tubes.The average sound absorption coefficient of the hollow tubular aluminum foam structure with cavity behind is 26%higher than that of the homogeneous aluminum foam structure with cavity behind in the frequency range of 1 000～6 300 Hz.