Asymptotic Solutions of Biot’s Equations by Complex Ray Tracing
نویسندگان
چکیده
Abstract. Acoustic waves in porous media are subject to dispersion and strong attenuation. A rigorous asymptotic solution of Biot’s equation involves a complex eikonal function and its numerical implementation requires complex space-time ray tracing. Attenuation is represented by the imaginary part of the eikonal. Non-negativity of timeaveraged dissipation in time-periodic motions implies that the imaginary part of the eikonal is non-decreasing along the direction of the energy flux.
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