Discontinuities in Acoustic Wave-Guide and the Reciprocity Nick V. Solokhin

This work includes numerical analysis of discontinuities in acoustic wave-guide and their properties in multi-mode case. It was suggested new version of reciprocity relations between wave-guide modes: between incident and transmitted and between incident and reflected modes. This new version of reciprocity relations transforms into old one in a case of single traveling mode. Это и многое другое вы найдете в книге Discontinuities in Acoustic Wave-Guide and the Reciprocity (Nick V. Solokhin)