Modeling of Thrust Properties for Capillary-Type Pulsed Plasma Thrusters Using Electrothermal Discharge in Teflon

Abstract

Pulsed plasma thrusters (PPTs) are preferred low-power systems for satellites because of their simplicity and small dimensions. This article was carried out to discuss and calculate the basic parameters that describe the efficiency of the electrothermal type of PPTs, using the 1-D time-depending ETFLOW model of the electrothermal capillary discharge with Teflon capillary. Parameters, such as the ablated mass, thrust, impulse, and specific impulse, were calculated. In addition, the basic plasma parameters, such as temperature, pressure, density, velocity, and heat flux, were all studied as a function of discharge time. We also discussed the effect of using an approximation of the transmission heat factor of Teflon. The influences of some input parameters as applied voltage and capillary geometry on thruster parameters were studied. It was found that ablated mass increases with the applied voltage or capillary length and decreases as the capillary diameter increases. Finally, calculations were compared to the measured results of ablated mass, impulse, and specific impulse from different works. The results of our model are in good agreement with experimental results with small variations in impulse and specific impulse values. Variations are expected to be limited if we enter some modifications to the model to increase the exit velocity and use the radial dimension for calculations.