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Published on: December 4, 2017
Nonlinear acoustic wave equations with fractional loss operators
1Department of Informatics, University of Oslo, P.O. Box 1080, NO-0316 Oslo, Norway. fabrice@ifi.uio.no
Fractional derivatives enhance wave propagation models for complex media, accurately simulating sound in biological tissues by incorporating attenuation and dispersion. This leads to a generalized nonlinear wave equation applicable to various acoustic phenomena.
Area of Science:
- Physics
- Acoustics
- Applied Mathematics
Background:
- Classical wave equations struggle to model complex media, particularly sound propagation in biological tissues.
- Existing models lack sufficient accuracy in representing attenuation and dispersion phenomena.
- Traditional constitutive equations in mechanics and heat conduction require advanced mathematical tools for complex media.
Purpose of the Study:
- To introduce fractional derivatives into classical wave equations for improved modeling of wave propagation.
- To develop a nonlinear wave equation that accurately captures attenuation and dispersion in complex media.
- To generalize existing wave equations, such as the Westervelt equation, using fractional calculus.
Main Methods:
- Modification of traditional constitutive equations using fractional derivatives.
- Derivation of a nonlinear wave equation incorporating fractional calculus.
- Application of fractional calculus to model attenuation and dispersion laws.
Main Results:
- Fractional derivatives effectively model wave propagation in complex media.
- The derived nonlinear wave equation accurately describes observed attenuation and dispersion.
- The study presents a fractional generalization of the Westervelt, Khokhlov-Zabolotskaya-Kuznetsov, and Burgers' equations.
Conclusions:
- Fractional derivatives offer a powerful framework for modeling complex wave phenomena.
- The developed fractional wave equation provides a more accurate description of sound propagation in biological tissues.
- This approach advances the understanding and modeling of nonlinear acoustics and wave physics.
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