NASA/TM-2005-213902, Reid, R.S. and Martin, J.J. and Schmidt, G.L., Method for Determination of <5 ppm Oxygen in Sodium Samples, George C. Marshall Space Flight Center, Marshall Space Flight Center, AL 35812, July 2005, pp. 80, Format(s): PDF 4550k |
Alkali metals used in pumped loops or heat pipes must be sufficiently free of nonmetallic impurities
to ensure long heat rejection system life. Life issues are well established for alkali metal systems.
Impurities can form ternary compounds between the container and working fluid, leading to
corrosion. This Technical Memorandum discusses the consequences of impurities and candidate
measurement techniques to determine whether impurities have been reduced to sufficiently low
levels within a single-phase liquid metal loop or a closed two-phase heat transfer system, such as
a heat pipe. These techniques include the vanadium wire equilibration, neutron activation analysis,
plug traps, distillation, and chemical analysis. Conceptual procedures for performing vanadium
wire equilibration purity measurements on sodium contained in a heat pipe are discussed in
detail.
| Keywords: | alkali metals, sodium, purity requirements, long-life heat pipes, refractory metals, corrosion, fission power systems, purity testing techniques |
|---|---|
| Subjects: | Astronautics: Spacecraft Propulsion And Power |
| ID Code: | 706 |
| Deposited On: | 26 September 2005 |