Propagation of Quasi-Lamb Waves in an Elastic Layer Interacting with a Viscous Liquid Half-Space

The propagating of quasi-Lamb waves in an elastic layer that interacts with a half-space of a viscous compressible fluid is studied. The three-dimensional linearized Navier–Stokes equations for the viscous fluid and the linear equations of the classical theory of elasticity for the elastic layer are used to plot the dispersion curves and to study the propagation of quasi-Lamb waves over a wide frequency range. The effect of the viscous compressible fluid and the thickness of the elastic layer on the phase velocities and attenuation coefficients of quasi-Lamb modes is analyzed. The approach developed and the results obtained allow establishing the limits of applicability of the ideal fluid model. The numerical results are presented in the form of graphs and analyzed.