An axisymmetric model of the heat and mass transfer in electrical contacts during short arc

The mathematical model has been developed that describes the dynamics of the temperature field in electrical contacts when they are heated by the heat flux of a short arc, which is considered to be multicomponent and dependent on the temperature of the arc and the contact spot. For the cathode, these components take into account ionic bombardment of the cathode, radiant heating by arc column, heating due to the emission of the reverse electrons, thermal emission cooling and power losses due to phase transitions. The power supplied to the anode includes heating due to the kinetic energy of the entering electrons and radiant heating by the arc column, and cooling for the consume of phase transformations.The model is based on the spherical Stefan problem with nonlinear boundary conditions and a special coefficient that takes into account a part of the ejected liquid melt. To solve it, an iterative method of majorant functions has been developed, which makes it possible to obtain sequences of overestimated and underestimated temperatures in the liquid and solid zones of the contact area, as well as the corresponding values of the erosion values.