The analytical mode is based on the theory of sound propagation in layered media . the concept of equivalent parameters is established . the absorption of sound energy by damping layer ' s is represented by use of complex sound impedance 解析模型以分层介质中的波动理论为基础，建立了等效参数的概念，并运用声阻抗的复数表示法把阻尼层对介质层声能吸收的影响都考虑进去，通过比较敷设消声覆盖层前后多层传递损失的差异来获得消声层的效率。
