Numerical simulation of electrophysical processes in high-current cathode nodes of low-temperature plasma generators

To correct account for the Joule heat release in cathodes of high-current plasma devices, it is necessary to solve the problem of the current flowing inside the cathode. In the present work, a numerical simulation using the Comsol Multiphysics is carried out to study the stationary electrophysical problem for axisymmetric cathode. The problem is based on the solution of the two-dimensional continuity equation with allowance for the boundary conditions for a composite cathode, which is a system of conjugated elements "tungsten cathode insert - copper cage". Based on the simulation results, stationary distributions of the electric potential and the density of electric current trough the body of the cathode are obtained. The features of the electric current and electric potential distribution in the cathode depending on the geometry of the model and the radius of the cathode spot are shown.