The effect of the tortuosity of fluid phases on the phase velocity of Rayleigh wave in unsaturated porothermoelastic media

Based on the frame of elastic theory for unsaturated porous medium, considering the influence of the thermal effect, the effects of the tortuosity of fluid phases on the phase velocity of Rayleigh wave in unsaturated porous media are studied. Firstly, the thermoelastic wave equations for three-phase porous media are established by taking into account the effect of the tortuosity of fluid phases. Secondly, through a theoretical derivation, the dispersion equation of Rayleigh wave for unsaturated porothermoelastic media is given by introducing the potential functions. Finally, the variations of the phase velocity of Rayleigh wave are analyzed with numerical examples. The results demonstrate that the phase velocity of Rayleigh wave is not just related to the frequency but also affected by the tortuosity of pore-fluid. The effect of the tortuosity of pore-liquid on the phase velocity of Rayleigh wave is more significant than that of the tortuosity of pore-gas on the phase velocity of Rayleigh wave.