Sizing and preliminary design of a 2-kW water propelled hall effect thruster
File(s)
Author(s)
Type
Conference Paper
Abstract
Having identified the potential of water as a breakthrough propellant for electric propulsion, URA Thrusters and Imperial College London present the preliminary design of a 2-kW level water vapor fueled Hall Effect thruster: the AQUAHET. The design of this new
thruster builds on the lessons learnt from the development at Imperial of an analogous oxygen
fueled thruster: the Water Electrolysis Hall Effect Thruster or WET-HET. Using a 1D version of Imperial College London’s fully kinetic particle-in-cell code PlasmaSim, we determine the optimum discharge channel sizing for the AQUAHET. The presence of multiple high specific
impulse and anode efficiency data points outputted by these analyses points to sources of unaccounted losses in the code. To verify PlasmaSim’s ability to accurately predict thruster performance with water vapor, we conduct an early prototype validation test campaign. For
these experiments existing WET-HET laboratory prototype hardware is adapted and tested at a channel length of roughly 13 mm, a channel mean diameter of 20 mm, and a channel width of 5 mm. Thrust data is collected with a hanging pendulum style thrust balance for mass flow rates of 1 mg/s of oxygen and water. For oxygen at discharge powers ranging from 710 to 1580 W we measure thrust up to 22 mN, specific impulse up to 2342 s, and anode efficiency up to 16.5%. For water at discharge power levels ranging from 860 to 1600 W we measure thrust up to 20 mN, specific impulse up to 2039 s, and anode efficiency up to 12.5%. Comparison of this experimental data against PlasmaSim outputs underlines the code is not currently able to accurately predict water performance. We posit this is in part because the
model fails to correctly capture collision physics. In order to leave room for future experimental performance optimization, a modular AQUAHET thruster is designed with channel lengths of 7, 10, and 13 mm; a channel mean diameter of 20 mm; and channel widths of 3, 4, and 5 mm. We also present here the updated magnetic topology of the AQUAHET breadboard thruster.
thruster builds on the lessons learnt from the development at Imperial of an analogous oxygen
fueled thruster: the Water Electrolysis Hall Effect Thruster or WET-HET. Using a 1D version of Imperial College London’s fully kinetic particle-in-cell code PlasmaSim, we determine the optimum discharge channel sizing for the AQUAHET. The presence of multiple high specific
impulse and anode efficiency data points outputted by these analyses points to sources of unaccounted losses in the code. To verify PlasmaSim’s ability to accurately predict thruster performance with water vapor, we conduct an early prototype validation test campaign. For
these experiments existing WET-HET laboratory prototype hardware is adapted and tested at a channel length of roughly 13 mm, a channel mean diameter of 20 mm, and a channel width of 5 mm. Thrust data is collected with a hanging pendulum style thrust balance for mass flow rates of 1 mg/s of oxygen and water. For oxygen at discharge powers ranging from 710 to 1580 W we measure thrust up to 22 mN, specific impulse up to 2342 s, and anode efficiency up to 16.5%. For water at discharge power levels ranging from 860 to 1600 W we measure thrust up to 20 mN, specific impulse up to 2039 s, and anode efficiency up to 12.5%. Comparison of this experimental data against PlasmaSim outputs underlines the code is not currently able to accurately predict water performance. We posit this is in part because the
model fails to correctly capture collision physics. In order to leave room for future experimental performance optimization, a modular AQUAHET thruster is designed with channel lengths of 7, 10, and 13 mm; a channel mean diameter of 20 mm; and channel widths of 3, 4, and 5 mm. We also present here the updated magnetic topology of the AQUAHET breadboard thruster.
Date Issued
2022-06-19
Date Acceptance
2022-06-19
Citation
2022
Copyright Statement
© 2022 The Author(s).
Source
The 37th International Electric Propulsion Conference
Publication Status
Published
Start Date
2022-06-19
Finish Date
2024-06-23
Coverage Spatial
Cambridge, MA USA