High-temperature thermal storage systems for advanced solar receivers materials selections

Technical Report · Sat Sep 01 00:00:00 EDT 1990

DOI:https://doi.org/10.2172/6400590· OSTI ID:6400590

Wilson, D F; DeVan, J H; Howell, M

Advanced space power systems that use solar energy and Brayton or Stirling heat engines require thermal energy storage (TES) systems to operate continuously through periods of shade. The receiver storage units, key elements in both Brayton and Stirling systems, are designed to use the latent heat of fusion of phase-change materials (PCMs). The power systems under current consideration for near-future National Aeronautics and Space Administration space missions require working fluid temperatures in the 1100 to 1400 K range. The PCMs under current investigation that gave liquidus temperatures within this range are the fluoride family of salts. However, these salts have low thermal conductivity, which causes large temperature gradients in the storage systems. Improvements can be obtained, however, with the use of thermal conductivity enhancements or metallic PCMs. In fact, if suitable containment materials can be found, the use of metallic PCMs would virtually eliminate the orbit associated temperature variations in TES systems. The high thermal conductivity and generally low volume change on melting of germanium and alloys based on silicon make them attractive for storage of thermal energy in space power systems. An approach to solving the containment problem, involving both chemical and physical compatibility, preparation of NiSi/NiSi{sub 2}, and initial results for containment of germanium and NiSi/NiSi{sub 2}, are presented. 7 refs., 10 figs., 4 tabs.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: National Aeronautics and Space Administration (NASA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6400590
• Report Number(s): ORNL/TM-11587; ON: DE91002962
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
SOLAR RECEIVERS
LATENT HEAT STORAGE
SPACECRAFT POWER SUPPLIES
GERMANIUM
NICKEL ALLOYS
PHASE CHANGE MATERIALS
SILICON ALLOYS
SOLAR EQUIPMENT
THERMAL CONDUCTIVITY
THERMAL ENERGY STORAGE EQUIPMENT
ALLOYS
ELECTRONIC EQUIPMENT
ELEMENTS
ENERGY STORAGE
EQUIPMENT
HEAT STORAGE
MATERIALS
METALS
PHYSICAL PROPERTIES
POWER SUPPLIES
STORAGE
THERMODYNAMIC PROPERTIES
142000* - Solar Energy- Heat Storage- (1980-)
140700 - Solar Thermal Power Systems