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arXiv · 1805.04641

A note on the Riemann solutions to the isentropic Euler equations in the vanishing pressure limit

Sana Keita·Yves Bourgault
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Abstract

The behaviour of the solutions to the Riemann problem for the isentropic Euler equations when the pressure vanishes is analysed. It is shown that any solution composed of a 1-shock wave and a 2-rarefaction wave tends to a two-shock wave when the pressure gets smaller than a fixed value determined by the Riemann data; by contrast, any solution composed of a 1-rarefaction wave and a 2-shock wave tends to a two-rarefaction wave. The two situations are illustrated with numerical tests.

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Sana Keita, Yves Bourgault. 2018-05-12. A note on the Riemann solutions to the isentropic Euler equations in the vanishing pressure limit. https://arxiv.org/abs/1805.04641

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