非保守耦合结构间耦合损耗因子的计算

耦合损耗因子是表征耦合系统间能量传递特征的重要参数。本文应用统计能量分析理论,分析和研究了点和线非保守耦合平行板系统,给出了两种耦合情况下耦合损耗因子的计算公式。当耦合为保守情况时,公式可以简化,这些简化公式与1]中计算同一类型保守耦合损耗因子的公式完全一致。已经进行了一系列实验验证,实验测量数据与理论计算结果吻合较好,其误差在3dB以内。

Calculation of Coupling Loss Factor of Non-Conservatively Coupled Structures

Coupling loss factor(CLF) is an important Statistical Energy Analysis(SEA) parameter for characterizing energy transmission between coupled systems. Generally it is calculated by formula. The formula for calculating CLF varies with coupling types and coupled systems. Up to now, all the formulae given in reference1] for calculating CLF can only be suitable for conservatively coupled systems. In the present paper, the non-conservatively coupled parallel-plate systems are analyzed by using SEA. The formulae for calculating CLF of two parallel plates coupled through point and line damping have been derived by using wave propagation theory. The formulae can be reduced to those given in other papers for calculating CLF of the same coupled systems if coupling element is conservative, A series of experimental verifications has been carried out. The experimental set-up consists of two parallel plates of different thicknesses connected by point or line No. 64 damping material(made in a certain Chinese institute). The measured results are compared with the values calculated by the formulae derived in this paper. The agreement between measured and calculated results is quite satisfactory. The deviation, except for some frequencies, is within 3 dB.