ABSTRACT
The 1D calculations are derived from 2D fluid equations for electrons, ions, and neutrals, including Poisson's equation, but using approximations for the radial terms. This allows a smooth transition between the quasi-neutral plasma and anode sheath without any ambipolar transport assumptions. Transport coefficients are calculated from published cross-sections and include electron-ion interactions. Boundary conditions at the anode surface for particle and heat fluxes are derived from simple kinetic considerations. Transport contributions from temperature gradients (thermal diffusion) are neglected. The radial terms are evaluated by assuming a step function dependence on the radial current density. To obtain convergence, a continuation scheme was used starting with axial LTE solutions, then one and two-temperature quasi-neutral solutions, and then the full two-component solution.
