HIGH TEMPERATURE SOLAR THERMIONIC GENERATORS.
Abstract
Efforts during this quarter included the fabrication of four Series 300 thermionic converters and the initiation of sustained performance evaluations of three of the four. One of the converters ( 302) is being operated continuously while the other two ( 303 and 305) are being cycled to simulate the 55 minute ON, 35 minute OFF orbital cycle operation. Design emitter temperature is 2000 K and nominal output power to the load at 0.7 volts is 21 watts (7 watts/cm sq). To date, (through October 31, 1963) a total of 545 hours of continuous operation has been recorded for converter 302 with no decrease in performance. Converter 303 withstood a total of 430 cycles when an apparent internal emitter-to-collector short occurred. A failure analysis is currently being performed on this converter. Converter 305 has accumulated a total of 540 cycles. Performance data taken during cycle 509 showed a 17.5% decrease in power output. During the last 32 cycles the performance has held essentially constant at the reduced power output. Test of this converter is continuing. In addition to the above described fabrication and test effort, a Demonstrator Model Test Stand and Auxiliary Support Vacuum System was fabricated and tested. This equipment was used during the acceptance test of converter 304 and met or exceeded all performance specifications. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 15, 1963
- Accession Number
- AD0423713