The unstructured mesh methods described above have been also applied in problems with a complicated boundary shape.

In [7] the equations were supplemented by
additional equations for variables *p* and *v*; this system
is known as Compressional Reduced MHD.
[7, 8].
The equations were solved on the computational mesh
shown, at a low resolution of 800 mesh points for clarity, in
Fig.9(a). The contours of the equilibrium magnetic
flux are shown in Fig.9(b).

In [8] the equations were solved in three
dimensions, in the CRMHD approximation, where the third
dimension was discretized by finite differences.
The grid in the *x*,*y* plane was independent of the
third coordinate. The *x*,*y* grid was similar to
that of Fig.9(a).

Finally the finite element discretization described here is
being combined with an existing 3D MHD code to give a
highly flexible and powerful method for solving 3D nonlinear
MHD problems in complex geometry [9].
Again the *x*,*y* grid is independent of the third coordinate,
which is discretized using Fourier series.

Wed Jan 7 14:07:46 EST 1998