Pressure waves in elastic tube with polymeric liquid

Propagation of acoustic waves in an elastic tube with compressible polymeric liquid is investigated. A dispersion equation is derived that accounts for viscoelastic effects in the fluid in coupling with inertia, radial and longitudinal deformations of the tube's wall. The equation is valid in the frequency range where sound wave length is greater from the tube radius and includes the Korteweg- Joukowski speed of water hammer as a limiting case. Analysis of the dispersion relation has shown a strong influence of the rheological properties of the liquid on dispersion and attenuation of pressure signals. The results indicate also that the model developed could give means to characterize the rheological parameters of a polymeric liquid with sufficiently simple acoustic technique.