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International space station cathode life testing
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Soulas, George C. Sarver-Verhey, Timothy R. |
| Copyright Year | 1997 |
| Description | Four hollow cathode assembly (HCA) life tests were initiated at operating conditions simulating on-orbit operation of the International Space Station plasma contactor. The objective of these tests is to demonstrate the mission-required 18,000 hour lifetime with high-fidelity development model HCAS. HCAs are operated with a continuous 6 sccm xenon flow rate and 3 A anode current. On-orbit emission current requirements are simulated with a square waveform consisting of 50 minutes at a 2.5 A emission current and 40 minutes with no emission current. One HCA test was terminated after approximately 8,000 hours so that a destructive analysis could be performed. The analysis revealed no life-limiting processes and the ultimate lifetime was projected to be greater than the mission requirement. Testing continues for the remaining three HCAs which have accumulated approximately 8,000 hours, 10,000 hours, and 11,000 hours, respectively, as of June 1997. Anode and bias voltages, strong indicators of cathode electron emitter condition, are within acceptable ranges and have exhibited no life- or performance-limiting phenomena to date. |
| File Size | 665369 |
| Page Count | 12 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19970041514 |
| Archival Resource Key | ark:/13960/t2c877922 |
| Language | English |
| Publisher Date | 1997-11-01 |
| Access Restriction | Open |
| Subject Keyword | Spacecraft Design, Testing And Performance Electric Potential Hollow Cathodes International Space Station Bias Continuum Flow Xenon Contactors Waveforms Flow Velocity Emitters Space Plasmas Accumulations Ntrs Nasa Technical Reports ServerĀ (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |