Three-dimensional MHD simulations of forced magnetic reconnection

Results are presented from MHD simulations of three-dimensional flows of a high-conductivity plasma in the vicinity of a null point of a magnetic fiel d. The excitation of an electric current at the boundary of the computation region results in self-consistent plasma flows and change in the structure of the magnetic field. Generally, in the vicinity of a null point, an MHD singularity arises that manifests itself in the formation of locally plane current sheets. It is shown that the current sheet can be oriented either a long the separatrix surface of a magnetic configuration or perpendicular to it, except for axisymmetric configurations (or close to them), when the ex citation of an electric current in the direction orthogonal to the separatr ix surface does not lead to the formation of a current sheet. (C) 2001 MAIK "Nauka/Interperiodica".