Parametric Study of a Cathode-Less Radio Frequency Thruster
Mirko Magarotto, Daniele Pavarin
Abstract
A cathode-less radio frequency (RF) thruster is a plasma-based system for space propulsion. It consists on a source for plasma generation driven by an RF antenna and a magnetic nozzle for the acceleration of the exhausted plasma stream. A parametric analysis has been conducted in order to evaluate the influence of some key design parameters on the performances of such a thruster. Specifically, the intensity and the topology of the magneto-static field, along with the antenna geometry have been varied. Their influence has been assessed on the plasma parameter profiles within the source (i.e., electron density, electron temperature, and power deposition), the antenna properties (i.e., impedance and current distribution), and the propulsive performances (i.e., thrust and specific impulse). The results presented in this work have been obtained with the validated code 3D-VIRTUS. The latter solves self-consistently both the electro-magnetic wave propagation and the plasma transport within a source driven by a RF antenna. An analytical model has been subsequently employed in order to solve the plasma dynamics in the plume and, in turn, to estimate the propulsive performances.