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Optical diagnostic characterization of high-power hall thruster wear and operation
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Kamhawi, Hani Soulas, George C. Williams Jr., George J. |
| Copyright Year | 2012 |
| Description | Optical emission spectroscopy is employed to correlate BN insulator erosion with high-power Hall thruster operation. Specifically, actinometry leveraging excited xenon states is used to normalize the emission spectra of ground state boron as a function of thruster operating condition. Trends in the strength of the boron signal are correlated with thruster power, discharge voltage, and discharge current. In addition, the technique is demonstrated on metallic coupons embedded in the walls of the HiVHAc EM thruster. The OES technique captured the overall trend in the erosion of the coupons which boosts credibility in the method since there are no data to which to calibrate the erosion rates of high-power Hall thrusters. The boron signals are shown to trend linearly with discharge voltage for a fixed discharge current as expected. However, the boron signals of the higher-power NASA 300M and NASA 457Mv2 trend with discharge current and show an unexpectedly weak to inverse dependence on discharge voltage. Electron temperatures measured optically in the near-field plume of the thruster agree well with Langmuir probe data. However, the optical technique used to determine Te showed unacceptable sensitivity to the emission intensities. Near-field, single-frequency imaging of the xenon neutrals is also presented as a function of operating condition for the NASA 457 Mv2. |
| File Size | 721242 |
| Page Count | 26 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20150007664 |
| Archival Resource Key | ark:/13960/t47q4060h |
| Language | English |
| Publisher Date | 2012-07-29 |
| Access Restriction | Open |
| Subject Keyword | Spacecraft Propulsion And Power Electric Potential Performance Tests Xenon Imaging Techniques Insulators Optical Emission Spectroscopy Electrostatic Probes Hall Thrusters Boron Emission Spectra Wear Near Fields Models Actinometers Erosion Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
