V.T.Grinchenko, G.L.Komissarova Properties of wave motions in a fluid-filled cylinder, localized near the boundaries |
Acoustic bulletin, Vol. 9 ¹ 2, (2006) |
| Properties of harmonic surface waves in a fluid-filled elastic cylinder are investigated. Wave motion in a composite waveguide is described on the basis of the complete systems of equations of dynamic elasticity theory and equations of motion of ideal compressed liquid. An asymptotic analysis of the dispersion relations for large wave numbers and quantitative analysis of the dispersion spectrum show the fundamental difference between the properties of the surface waves in the waveguides with the compliant and rigid walls. In both cases, with increasing wavenumber, the first normal mode on the internal surface of the cylinder forms at the limit the Stoneley wave. For the compliant cylinder's material, the second normal wave on the external surface forms at the limit the Rayleigh wave. In the case of the rigid cylinder, the surface wave on the external surface does not exist as a limiting form of one of the normal waves of the waveguide, but the motions like the Rayleigh wave are formed only on separate segments of different dispersion curves. Moreover, for the compliant and rigid materials of the cylinders the essential distinction is also observed in the limiting values of phase velocities for the waves of higher orders. |
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KEY WORDS: an elastic-liquid waveguide, the dispersion picture, normal waves, the Stoneley wave, the Rayleigh wave |
| TEXT LANGUAGE: Russian |