Global plasma modeling of an air-breathing gridded-ion thruster for very low Earth orbit applications

A volume-averaged (zero-dimensional) global model of an atmospheric nitrogen–oxygen mixture is proposed. This model is used to predict the performance of an air-breathing electric gridded-ion thruster. Based on particle and energy balance equations, it computes the densities and temperatures of the different species in the discharge chamber and evaluates the thrust generated by ions extracted from the plasma and accelerated between two grids. Simulation results over a range of input radio frequency (RF) powers and altitudes are used to assess the feasible operating regimes and to identify the main limiting mechanisms. Coupling the global model with a simplified drag analysis indicates that satellite operation should be feasible at altitudes between 200 and 250 km, for RF power levels ranging from 1.5 to 3 kW. However, certain limitations associated with the gas compression system and drag estimation deserve further investigation.