Abstract
Small nonstationary perturbations in a viscous heat-conducting compressible medium are analyzed on the basis of the linearization of the complete system of hydrodynamic equations for small Knudsen numbers (Kn ≪ 1). It is shown that the density and temperature perturbations (elastic perturbations) satisfy the same wave equation which is an asymptotic limit of the hydrodynamic equations far from the inhomogeneity regions of the medium (rigid, elastic or fluid boundaries) as M a = v/a → 0, where v is the perturbed velocity and a is the adiabatic speed of sound. The solutions of the new equation satisfy the first and second laws of thermodynamics and are valid up to the frequencies determined by the applicability limits of continuum models. Fundamental solutions of the equation are obtained and analyzed. The boundary conditions are formulated and the problem of the interaction of a spherical elastic harmonic wave with an infinite flat surface is solved. Important physical effects which cannot be described within the framework of the ideal fluid model are discussed.
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REFERENCES
S. Chapman and T. G. Cowling, The Mathematical Theory of Non-UniformGases, Univ. Press, Cambridge (1952).
J. F. Clarke and McChesney, The Dynamics of Real Gases, Butterworths, London (1964).
A. D. Khonkin, “Paradox of infinite perturbation propagation velocity in the hydrodynamics of a viscous heat-conducting medium and equations of hydrodynamics of fast processes,” Aeromechanics [in Russian], Nauka, Moscow, 289–299 (1976).
D. I. Blokhintsev, Acoustics of an Inhomogeneous Moving Medium [in Russian], Nauka, Moscow (1981).
M. A. Leontovich, “Observations on the theory of acoustic absorption in gases,” Zh. Teor. Exp. Fiz., 6, 561–576 (1936).
L. D. Landau and E. M. Lifshits, Theoretical Physics. V. 6. Hydrodynamics [in Russian], Nauka, Moscow (1986).
M. B. Vinogradova, O. V. Rudenko, and A. P. Sukhorukov, Theory of Waves [in Russian], Nauka, Moscow (1979).
J. W. Strutt (Baron Rayleigh), The Theory of Sound, Macmillan, London (1926).
V. Ya. Neiland and V. V. Sychev, “Asymptotic solutions of the Navier-Stokes equations in regions with large local perturbations,” Fluid Dynamics, 1, No.4, 29–33 (1966).
M. Van Dyke, Perturbation Methods in Fluid Mechanics, Academic Press, New York & London (1964).
B. P. Konstantinov, “On the absorption of acoustic waves reflected from a solid boundary,” Zh. Tekhn. Fiz., 9, No.3, 226–238 (1939).
V. A. Murga, “Acoustic field of a point source near a rigid plane in a viscous compressible fluid,” Akust. Zh., 35, No.1, 97–100 (1989).
I. Sneddon, Fourier Transforms, McGraw-Hill, New York, etc. (1951).
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Translated from Izvestiya Rossiiskoi Academii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, 2005, pp. 76–87.
Original Russian Text Copyright © 2005 by Stolyarov.
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Stolyarov, E.P. Asymptotic Solutions of the Equations for a Viscous Heat-Conducting Compressible Medium. Fluid Dyn 40, 403–412 (2005). https://doi.org/10.1007/s10697-005-0080-x
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DOI: https://doi.org/10.1007/s10697-005-0080-x