HIGH TEMPERATURE SOLAR THERMIONIC GENERATORS.
Abstract
A total of 2322 hours of continuous operation has been recorded for converter 302 with no apparent degradation in output power. This converter is operating at an emitter temperature of 2000K with a power output of 18.2 watts (0.7 V 26 amps). Although many life limiting features of the design were determined, it has been concluded that several failures, which occurred at the seal metal-to-ceramic brazes, resulted from having overheated the seal structures during acceptance testing. The preliminary design of a solar thermionic generator was also completed and this design dictated the shape of the Series 310 converter emitter head to conform to a four converter generator cavity wall. The generator, with emitters operating at 2000K is rated at 66 watts 4.0 volts or 108 watts at 3.0 volts. The generator assembly utilized four Series 310 converters arranged symmetrically about the solar concentrator optical axis such that the emitters form a solar cavity receiver. The configuration is such that any converter can be removed and replaced with a minimum of difficulty. The ground rules established prior to the initiation of the generator design calculation are presented herein. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 15, 1964
- Accession Number
- AD0439652