VMEC

The three-dimensional Variational Moments Equilibrium Code (VMEC) minimizes the energy functional

$W=\underset{{\omega }_p}{\int }(\frac{1}{2}{B}^2+p)dV$

over the toroidal domain ω_p. The solution is obtained in flux co-ordinates (s, θ, ζ), related to the cylindrical co-ordinates (R, φ, Z) by

$R=\sum R_{mn}\cos (m\theta -n\zeta )$

$Z=\sum Z_{mn}\sin (m\theta -n\zeta )$

The code assumes nested flux surfaces.

Implementations of the code

The code is being used at:

• IPP-Garching, Germany
• LNF, Spain

Enhancements / extensions of the code

• NEMEC
• DIAGNO
• MFBE