Determination of fields near an ICRH antenna using a 3D magnetostatic Laplace formulation

In the vicinity of an ICRH antenna strap, where there are no volume currents and a free-space wavelength is much longer then the dimensions of interest, Ampere's law reduces to a curl-free conditions on the magnetic field, allowing a magnetic scalar potential to be defined. This scalar potential is a solution of the three-dimensional (3D) Laplace equation and satisfies the following boundary conditions on the magnetic field: the line integral of the magnetic field around the current strap is equal to the current flowing in the strap and the perpendicular component of the magnetic field vanishes at conductor surfaces (no flux penetration of perfect conductors). This formulation allows for the magnetic field solution of quite complex 3D geometries, such as poloidal current straps with asymmetric radial feeds or detailed Faraday shield geometries. 5 figs