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arXiv · 0707.0094

Study of the linear ablation growth rate for the quasi isobaric model of Euler equations with thermal conductivity

Olivier Lafitte
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Abstract

In this paper, we study a linear system related to the 2d system of Euler equations with thermal conduction in the quasi-isobaric approximation of Kull-Anisimov [14]. This model is used for the study of the ablation front instability, which appears in the problem of inertial confinement fusion. This physical system contains a mixing region, in which the density of the gaz varies quickly, and one denotes by L0 an associated characteristic length. The system of equations is linearized around a stationary solution, and each perturbed quantity is written using the normal modes method. The resulting linear system is not self-adjoint, of order 5, with coefficients depending on x and on physical parameters $α, β$. We calculate Evans function associated with this linear system, using rigorous constructions of decreasing at $\pm \infty$ solutions of systems of ODE. We prove that for $α$ small, there is no bounded solution of the linearized system.

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Olivier Lafitte. 2007-07-01. Study of the linear ablation growth rate for the quasi isobaric model of Euler equations with thermal conductivity. https://arxiv.org/abs/0707.0094

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