Peculiarities of interaction of cathode stream with anode vapors in a vacuum arc

A one-dimensional quasi-stationary model of the plasma zone of the vacuum arc is considered in terms of a three-liquid hydrodynamics approximation. It is supposed that atoms evaporated from the anode are ionized in a narrow near-anode zone, slow ions are rapidly maxwellized at the cost of Coulomb collisions and the ion braking length of the cathode stream may be comparable with a gap size, i.e. the cathode stream breaking is important. Outside the narrow near-electrode zones, slow anode and rapid cathode ions flows are maintained, the electron thermal conductivity equalizes the electron temperature.