Approximate Theory of Sound Propagation in a Bounded Viscoelastic Medium with Cylindrical Channels.

The acoustic characteristics of a cylindrical viscoelastic tube of finite length with a radially fixed outer surface replacing the hexagonal unit cell of a segment of a micro-inhomogeneous medium with cylindrical channels are calculated. The least-action principle and the hypothesis of plane sections are applied. A dispersion relation for longitudinal sound waves in a tube is found, which coincides with the approximations of the exact dispersion relation and has a form typical of micro-inhomogeneous resonant media. From a suitable approximation of the results of known measurements of the reduced input conductance of "semi-infinite" samples, the frequency dependence of the complex shear modulus of the rubber used is found. [ABSTRACT FROM AUTHOR]