A Four Function Variational Principle for Barotropic Magnetohydrodynamics
نویسنده
چکیده
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 ~ B the velocity field ~v and the density ρ. In this work I will improve on the previous results showing that non-stationary magnetohydrodynamics should be described by four functions .
منابع مشابه
Simplified Variational Principles for Barotropic Magnetohydrodynamics
Variational principles for magnetohydrodynamics were introduced by previous authors both in Lagrangian and Eulerian form. In this paper we introduce simpler Eulerian variational principles from which all the relevant equations of barotropic magnetohydrodynamics can be derived. The variational principle is given in terms of six independent functions for non-stationary barotropic flows and three ...
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