A theoretical model for the thrust and voltage of applied-field MPD thrusters

Abstract

The new visualization of applied-field MPD thruster operation offered by previous numerical simulations with the MACH2 code, is utilized to produce an analytic model. This model provides simple expressions for the thrust and voltage drop across the plasma that capture all the trends and in most cases the magnitudes of a wide range of experimental data. It establishes that the thrust scales as the square root of the product of the applied field strength, discharge current and mass flow rate, T~VrhlB~. Voltage scales linearly with applied field strength and is independent of discharge current and mass flow rate. This model also provides additional insights that can be utilized to improve applied-field MPD thruster performance.