Magnetohydrodynamic Bernoulli invariant
= Magnetohydrodynamic Bernoulli invariant
{title2=$\epsilon(\psi)$}
Along a steady axisymmetric ideal-MHD wind, the total specific <energy>
$$
\epsilon=\frac12|\mathbf u|^2+\Phi+h
-\frac{r\omega B_\phi}{\mu_0k}
$$
is constant on each magnetic surface. The last term is the <electromagnetic energy> transported per unit <mass> flux.