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Plasma contactor research - 1991
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Buchholtz, Brett Williams, John D. Wilbur, Paul J. |
| Copyright Year | 1992 |
| Description | A report describing the operating principles of hollow-cathode-based plasma contactors emitting or collecting electrons from an ambient plasma is summarized. Preliminary experiments conducted to determine the noise generated by these plasma contactors in the emission-current return line and in the plasma near it are described. These noise data are measured as current fluctuations in the return line and to the Langmuir probe and then analyzed using a fast Fourier transform technique. The spectral compositions of the data are characterized using power spectral density plots which are examined to identify possible noise source(s) and production mechanism(s). The precautions taken in the construction and calibration of the instrumentation to assure adequate frequency response are described. Experimental results show that line-current noise levels are typically 2 percent of the electron current being emitted or collected. However, noise levels increase to as much as 20 percent of the electron current at a few electron-collection operating conditions. The frequencies associated with most of the noise were harmonics of the 60 Hz input to system power supplies. Plasma noise had characteristics similar in magnitude and frequency to those for the return-line noise, but they contained additional features at frequencies considered to be related to ion-acoustic instabilities. Also discussed is a new probe positioning system built to facilitate future plasma-contractor research. |
| File Size | 1826596 |
| Page Count | 72 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19920016032 |
| Archival Resource Key | ark:/13960/t6rz45x70 |
| Language | English |
| Publisher Date | 1992-04-01 |
| Access Restriction | Open |
| Subject Keyword | Plasma Physics Hollow Cathodes Construction Fourier Transformation Calibrating Line Current Electromagnetic Noise Emission Spectra Noise Intensity Contactors Plasma Currents Electron Energy Plasma Electrodes Plasma Probes Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
