The Effect of Boundary Conditions on the Distribution of Physical Parameters in a High-Current Vacuum Arc Discharge

Through the use of a 2-D model of a high-current vacuum arc discharge (VAD) in an axial magnetic field, the distribution of high-current VAD parameters in a plasma area was calculated for different boundary conditions on the cathode plasma boundary, the anode, and the side boundary of plasma. Calculations were made for different current and external magnetic field values. The cathode boundary of plasma was assumed as either equipotential or having specified current density distribution. The side boundary of plasma coincided with either the external ion trajectory or the boundary of the calculated area. In the case with a specified current density, potential distribution on the cathode plasma boundary was calculated. There is a significant difference in the distribution of high-current VAD parameters when calculations are made with the use of models having different boundary conditions. A possibility of different-boundary-condition application for the adequate description of a high-current VAD is discussed. A simple mathematical model has been used for a vivid interpretation of the obtained results.