This project concentrates on the application of an out-of-core NETCON (new thermionic converter) to a space nuclear-power system. The emitters are typically 0.5 cm in dimension. The emitter and collector are separated by less than 0.5 mils (/12 microns), with operation in the quasi-vacuum (unignited) mode. The inter-electrode gap is set by the thermal expansion of a ceramic pedestal supporting the emitter. Heat transport to the emitter is by radiation. A good lead efficiency, typically 10 percent or more, is achievable at a relatively low emitter temperature of 1300 K and a collector temperature 850 K. This contrasts with an emitter temperature of 1700 K or more for the normal, ignited-mode converter. Systems analysis and a proof-of-principle NETCON cell will be constructed and tested for reliability in Phase I. Phase II will begin the product development of an out-of-core NETCON for application with a nuclear reactor.
Potential Commercial Applications: Low work function collectors (/1 eV) will result in high thermionic converter efficiency at low collector temperature for solar and other terrestrial power systems.STATUS: Project Proceded to Phase II
