A Four Function Variational Principle for Barotropic Magnetohydrodynamics

Asher Yahalom

doi:10.1209/0295-5075/89/34005

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arXiv · 0811.2309

A Four Function Variational Principle for Barotropic Magnetohydrodynamics

Asher Yahalom

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Abstract

Variational principles for magnetohydrodynamics were introduced by previous authors both in Lagrangian and Eulerian form. In a previous work Yahalom & Lynden-Bell introduced a simpler Eulerian variational principles from which all the relevant equations of magnetohydrodynamics can be derived. The variational principle was given in terms of six independent functions for non-stationary flows and three independent functions for stationary flows. This is less then the seven variables which appear in the standard equations of magnetohydrodynamics which are the magnetic field $\vec B$ the velocity field $\vec v$ and the density $\rho$. In this work I will improve on the previous results showing that non-stationary magnetohydrodynamics should be described by four functions .

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BibTeX RIS

Asher Yahalom. 2008-11-14. A Four Function Variational Principle for Barotropic Magnetohydrodynamics. https://doi.org/10.1209/0295-5075%2F89%2F34005

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