MODELING PLASMA PROCESSES IN 1-KILOWATT HYDRAZINE ARCJET THRUSTERS

This paper presents predictions of a nonequilibrium 1-kW hydrazine arc jet model with sensitivity studies on generalized Ohm's law and electr on-molecule inelastic collision factor delta. This model treats steady -state, two-dimensional, axisymmetric, two-temperature (electrons and heavy species), chemical nonequilibrium viscous flow, and includes flo w swirl and anode heat transfer in a converging-diverging nozzle. Key results indicate that the arcjet flow is in thermal and chemical noneq uilibrium. Sensitivity studies show that the modeling of the inelastic coupling of electrons-molecules significantly alters the predicted an ode current attachment location and, subsequently, the predicted plasm a voltage drop, and that the electron pressure gradient term does not significantly affect the current distribution. With an appropriate cho ice of delta, and adopting values from the literature for the cathode and anode sheath voltages, the model predictions are in good agreement with the experimental values.