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arXiv · 2010.00205

The vacuum boundary problem for the spherically symmetric compressible Euler equations with positive density and unbounded entropy

Calum Rickard
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Abstract

Global stability of the spherically symmetric nonisentropic compressible Euler equations with positive density around global-in-time background affine solutions is shown in the presence of free vacuum boundaries. Vacuum is achieved despite a non-vanishing density by considering a negatively unbounded entropy and we use a novel weighted energy method whereby the exponential of the entropy will act as a changing weight to handle the degeneracy of the vacuum boundary. Spherical symmetry introduces a coordinate singularity near the origin for which we adapt a method developed for the Euler-Poisson system by Guo, Had\v{z}i\'c and Jang to our problem.

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Calum Rickard. 2020-10-01. The vacuum boundary problem for the spherically symmetric compressible Euler equations with positive density and unbounded entropy. https://doi.org/10.1063/5.0037656

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