Regularities of heat- and mass transfer and evaporation of activators of thermoemissive cathodes

The problem of heat- and mass transfer and evaporation of emission-activating elements of refractory rod cathodes is formulated and solved in the 2D approximation with nonlinear boundary conditions. Time-dependent heat conduction equations, current continuity equations, as well as the diffusion equations and equations describing evaporation of activators are formulated simultaneously and solved numerically taking into account the temperature dependence of the electrode material. The thermal state of cathode assemblies depending on extrinsic parameters of plasma units is analyzed. The results of simulation of the thermal state and heat- and mass transfer in cathode assemblies with different geometries are considered.