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arXiv · 2104.09870

Asymptotic behaviors for Blackstock's model of thermoviscous flow

Abstract

We study a fundamental model in nonlinear acoustics, precisely, the general Blackstock's model (that is, without Becker's assumption) in the whole space $\mathbb{R}^n$. This model describes nonlinear acoustics in perfect gases under the irrotational flow. By means of the Fourier analysis we will derive $L^2$ estimates for the solution of the linear homogeneous problem and its derivatives. Then, we will apply these estimates to study three different topics: the optimality of the decay estimates in the case $n\geqslant 5$ and the optimal growth rate for the $L^2$-norm of the solution for $n=3,4$; the singular limit problem in determining the first- and second-order profiles for the solution of the linear Blackstock's model with respect to the small thermal diffusivity; the proof of the existence of global (in time) small data Sobolev solutions with suitable regularity for a nonlinear Blackstock's model.

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BibTeXRIS

Wenhui Chen, Ryo Ikehata, Alessandro Palmieri. 2021-08-17. Asymptotic behaviors for Blackstock's model of thermoviscous flow. https://doi.org/10.1512/iumj.2023.72.9425

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