Niobium-1 percent zirconium/potassium life-test heat pipe design and testing
Abstract
Studies are being conducted to develop lifetime performance data on heat pipes for the SP-100 reference flight system radiator. Experimental lifetime performance studies currently in progress use niobium-1 percent zirconium (Nb-1Zr) heat pipes with potassium (K) as the working fluid. A heat pipe life-test matrix has been developed for testing nine heat pipes; the variable parameters of the experimental matrix are established as steady operating temperature and input heat flux density. Impurity levels are being evaluated in the heat pipe materials before and after testing. Eight Nb-1Zr/K heat pipes were designed, fabricated, and tested. These are gravity-assist heat pipes operating in a reflux mode. The heat pipes are operating at between 800 and 900 K, with heat input fluxes of 13.8 to 30 W/sq cm. Two of the heat pipes have been in operation for over 13,000 hours, three over 10,000 hours, and three over 7000 hours.
- Publication:
-
AIAA, Aerospace Sciences Meeting
- Pub Date:
- January 1990
- Bibcode:
- 1990aiaa.meetV....S
- Keywords:
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- Alkali Metals;
- Heat Pipes;
- Hot Corrosion;
- Liquid Metals;
- Niobium Alloys;
- Service Life;
- Potassium;
- Spacecraft Radiators;
- Working Fluids;
- Zirconium Alloys;
- Fluid Mechanics and Heat Transfer