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arXiv · 0802.0609

A variational principle for two-fluid models

Sergey Gavrilyuk·Henri Gouin·Yurii Perepechko
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Abstract

A variational principle for two-fluid mixtures is proposed. The Lagrangian is constructed as the difference between the kinetic energy of the mixture and a thermodynamic potential conjugated to the internal energy with respect to the relative velocity of phases. The equations of motion and a set of Rankine-Hugoniot conditions are obtained. It is proved also that the convexity of the internal energy guarantees the hyperbolicity of the one-dimensional equations of motion linearized at rest.

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Sergey Gavrilyuk, Henri Gouin, Yurii Perepechko. 2008-02-05. A variational principle for two-fluid models. https://doi.org/10.1016/s1251-8069(97)80186-8

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