Influence of design and operation parameters on Hall thruster performances

Abstract

A stationary, macroscopic model [E. Ahedo, J. Gallardo, and M. Martı́nez-Sánchez, Phys. Plasmas 10, 3397 (2003)] is used to carry out parametric investigations on the effects of (i) the discharge voltage, (ii) the gas flow rate, (iii) the axial gradient of the magnetic field, and (iv) the chamber length on the Hall thruster performances and the axial structure of the plasma discharge. The high-thrust and high-specific-impulse modes for dual-mode thrusters are compared too. The results of the simulations agree well with the main tendencies observed in different experiments. The interaction among the several physical phenomena is discussed and useful scaling laws are proposed. Special attention is paid to understand (i) the adjustment of the magnetic field strength with the discharge voltage for optimum operation, (ii) the effect of the magnetic field shape, (iii) the dimensions of the different regions of the discharge, and (iv) the parameter trends needed to increment the propulsive and ionization efficiencies (the product of which determines the thrust efficiency).