Electrothermal Plenum Thruster Simulations Varying Input Pressure and Voltage
A radiofrequency electrothermal thruster is designed and simulated to create a low ionization energy plasma from a neutral propellant using a radio-frequency power. With an asymmetrical surface area ratio between the grounded and powered electrode, ion-neutral charge exchange collisions occurring within the propellant result in propellant heating. The Electrothermal Plenum Thruster conducts this propellant heating in an annular plenum chamber in attempt to maximize propellant heating. A software called CFD-ACE+ is utilized to demonstrate the effects of an enhanced sheath from the asymmetrical power coupling arrangement. Two sets of simulations are run to understand how input variables affect the plasma parameters of electron temperature and electron density. The first simulation series varies voltage input to the powered electrode to find that that the highest voltage of 500 V yielded the highest electron temperature at 63 eV, the strongest self-bias with the enhanced sheath at -165 V, and the greatest electron density at 9.15 × 1016 m-3. The second simulation series varies pressure input to the grounded electrode to find that the lowest pressure of 62 Pa provided the highest electron temperature at 32.1 eV, the strongest self-bias with the enhanced sheath at 128.3 V, and the greatest electron density at 6.41 ×1015 m-3. Compared to Pocket Rocket CFD simulation analysis, the Electrothermal Plenum Thruster performs at a higher level considering the peak electron temperature and electron density. The optimization of a micro-propulsion system such as this is important for increasing small satellite rapid maneuverability.
Ingram, Naomi N, "Electrothermal Plenum Thruster Simulations Varying Input Pressure and Voltage" (2022). ETD Collection for University of Texas, El Paso. AAI29211685.