ON THE PHASE AND GROUP VELOCITY OF THERMAOELASTIC RAYLEIGH WAVES IN TRANSVERSELY ISOTROPIC MATERIALS

Year 2014, Volume: 6 Issue: 1, 28 - 39, 01.03.2014

K. L. Verma

https://doi.org/10.24107/ijeas.251219

Abstract

Rayleigh wave speed in a heat conducting transversely isotropic material with thermal relaxation is studied. Phase and group velocity for the first four modes have been computed for aluminum alloy plate at different thermal relaxation times. It is observed that if modal phase velocity decrease with increasing frequency normally dispersive profiles, phase velocity is greater than group velocity and consequently carrier travels faster than the envelope. Thus in such cases if a phase disturbance appears at the beginning of the pulse, then it overtakes and finally it disappears in the front. Rayleigh wave speed is computed the medium and compared. It is observed that thermal relaxation time effect plays a significant role thermoelastic speed of Rayleigh waves at the low values of wave number limits

Keywords

Rayleigh waves, dispersion, phase velocity, group velocity, transversely isotropic material

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