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arXiv · 1205.6844

Linear relaxation to planar Travelling Waves in Inertial Confinement Fusion

Abstract

We study linear stability of planar travelling waves for a scalar reaction-diffusion equation with non-linear anisotropic diffusion. The mathematical model is derived from the full thermo-hydrodynamical model describing the process of Inertial Confinement Fusion. We show that solutions of the Cauchy problem with physically relevant initial data become planar exponentially fast with rate $s(\eps',k)>0$, where $\eps'=\frac{T_{min}}{T_{max}}\ll 1$ is a small temperature ratio and $k\gg 1$ the transversal wrinkling wavenumber of perturbations. We rigorously recover in some particular limit $(\eps',k)\rightarrow (0,+\infty)$ a dispersion relation $s(\eps',k)\sim γ_0 k^α$ previously computed heuristically and numerically in some physical models of Inertial Confinement Fusion.

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BibTeXRIS

Léonard Monsaingeon. 2012-05-30. Linear relaxation to planar Travelling Waves in Inertial Confinement Fusion. https://doi.org/10.1088/0951-7715%2F26%2F7%2F1891

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