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arXiv · 2107.03268

Linear stability of the Couette flow for the non-isentropic compressible fluid

Xiaoping Zhai
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Abstract

We are concerned with the linear stability of the Couette flow for the non-isentropic compressible Navier-Stokes equations with vanished shear viscosity in a domain $\mathbb{T}\times \mathbb{R}$. For a general initial data settled in Sobolev spaces, we obtain a Lyapunov type instability of the density, the temperature, the compressible part of the velocity field, and also obtain an inviscid damping for the incompressible part of the velocity field. Moreover, if the initial density, the initial temperature and the incompressible part of the initial velocity field satisfy some quality relation, we can prove the enhanced dissipation phenomenon for the velocity field.

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Xiaoping Zhai. 2021-07-07. Linear stability of the Couette flow for the non-isentropic compressible fluid. https://arxiv.org/abs/2107.03268

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