基于传递矩阵的汽车多层吸声材料特性研究

利用传递矩阵对汽车吸声材料的吸声特性进行了分析。首先将多层均匀吸声材料进行布置，得到两层吸声材料之间的声压与介质中质点的振动速度关系。然后将实验材料钢板前面的第i层与第i+1层吸声材料分离开来单独考虑，得到多层吸声材料的吸声系数计算公式。最后对三层不同厚度的均匀吸声材料之间的吸声系数进行了实例计算和实验测量，验证了传递矩阵计算所得的吸声系数是正确的。

A Study of Characteristics of Automobile Multilayer Sound Absorption Materials Based on Transfer Matrix

This paper analyzed the sound absorption characteristics of automobile sound absorption materials with the transfer matrix. Firstly, the multilayer uniform sound absorption materials were decorated, and the sound pressure and normal particle vibration velocity relationship between two layers of sound materials were obtained. Then the i layer and the i+1 layer of sound absorption materials in front of the experimental material steel plate were considered separately, and the acoustic impedance ratio between two layers was obtained.Thus, the sound absorption coefficient calculation formula of multilayer sound absorption materials would be given. Finally, instances calculation and experimental measurements of the sound absorption coefficient among the uniform sound absorption materials of three different thicknesses were carried out, and the correctness of the sound absorption coefficient was verified, which was studied from the transfer matrix characteristic calculation of automobile multilayer sound absorption materials. A theoretical basis for transfer matrix characteristics of the multilayer sound absorption materials will be provided.