基于传递矩阵法的声学覆盖层透射系数预报研究

Study on Prediction of Coating Acoustic Transmission Coefficient Based on Transfer Matrix Method

针对含周期单元声学覆盖层的透射系数计算方法展开研究,提出一种数值加解析的联合方法用于改善计算效率,首先以声阻抗管三水听器双负载法测试原理为基础,建立有限元模型并获取覆盖层的等效传递矩阵,结合多层均匀介质声透射解析理论计算覆盖层透射系数。为验证算法的准确性,将有限元直接计算结果与该算法计算结果对比,结果显示采用该算法在大部分频率范围内能准确预报透射系数。该方法可为有效优化声学覆盖层降噪性能提供理论支撑与方法指导。

The calculation method of transmission coefficient of acoustic coating with periodic element is studied.A numerical method combined with analytical method is proposed to improve the calculation efficiency.Firstly,based on the testing principle of acoustic impedance tube of three hydrophone and double load method,the finite element model is established and the equivalent transfer matrix of the coating is obtained.Combined with the analytical theory of sound transmission of multi-layer uniform medium,the transmission coefficient of the coating is calculated.In order to verify the accuracy of the algorithm,the direct finite element results are compared with those of the proposed method.The results show that this algorithm can accurately predict the transmission coefficient in most frequency range.This method provides a theoretical support and method guidance for effectively improving the noise reduction performance of acoustic coatings.