NASA Scientific and Technical Aerospace Reports

20040070749 Eagle-Picher Industries, Inc., Joplin, MO, USA
Small Capacity, Low Cost (Ni-H2) Design Concept for Commercial, Military, and Higher-Volume Aerospace
Applications
Cook, William; Smith, Ron; Wheeler, James; Space Electrochemical Research and Technology: Abstracts; [1991], pp. 41; In
English; See also 20040070726; No Copyright; Available from CASI only as part of the entire parent document
The development of Ni-Hsub2, cells in capacities of 20 ampere-hours (AH) or less has been delayed because of the initial
demand for development of the technology for larger satellites. Two cell designs are manufactured at Eagle-Picher which are
tailored to the specific requirements of the small satellite, not only in terms of power and volume, but also in terms of
economic feasibility. The RNH-12-1 is a 12 AH common pressure vessel design that has been manufactured, tested, and
delivered to Intraspace Corporation for use as a power source on the SPINSAT mission. The RNH-5-1 is a new design which
can be built in sizes from 5 through 120 AH in an IPV of CPV configuration. These two designs are based upon proven
manufacturing processes and component heritage and therefore retain the reliability and performance advantages of their
predecessors. Details of these two designs and their play in the "small sat" market will be described in this paper.
Author
Nickel Hydrogen Batteries; Spacecraft Power Supplies
20040070750 Sverdrup Technology, Inc., Brook Park, OH, USA
Mathematical Analyses of the Transport and Reaction Mechanisms in Solid Oxide Fuel Cells
Maloney, Thomas M.; Dees, Dennis W.; Space Electrochemical Research and Technology: Abstracts; [1991], pp. 43; In
English; See also 20040070726; No Copyright; Available from CASI only as part of the entire parent document
Computer models have been developed to quantitatively predict performance properties of high temperature H2O2, solid
oxide fuel cells. Current voltage relationships were estimated by analyzing effects due to charge transfer, surface migration,
and material transport within the solid electrolyte. Model parameters included electrical conductivity, electrolyte thickness,
reference exchange currents, and length of diffusion paths near the electrolyte surface.Results from the mathematical model
were in close agreement with experimental data for single cells at 1000 C and 1 atm. Results indicated that the solid electrolyte
thickness should be greater than 25 sq microns and the average fuel cell operating current density should exceed 250 mA/sq
cm to maintain high current efficiencies.
Author
Solid Oxide Fuel Cells; Mathematical Models
20040070929 NASA Marshall Space Flight Center, Huntsville, AL, USA
Subscale Testing of Nozzle Ablative Materials in a Supersonic Particle Impingement Environment
Howse, S.; Lawrence, T.; [2004]; 2 pp.; In English; JANNAF 14th NDES/23rd RNTS/36th S/MBS Joint Subcommittee
Meeting, 30 Mar. - 1 Apr. 2004, New Orleans, LA, USA; No Copyright; Avail: Other Sources; Abstract Only
Recent efforts to evaluate materials to replace the current NARC rayon used in the nozzle ablative of the NASA’s
Reusable Solid Rocket Motor (SRM), several tests were developed to look at the performance of supersonic particle impact
region of the aft exit cone. It was seen in early testing that some potential candidates did not perform as well as the current
NARC based material and so the 24 inch Solid Rocket Motor (SRTM) exit cone design was extended and contoured to induce
particle impingement in the aft end. The SRTM testing provided a larger testbed to evaluate the results seen in the Solid Fuel
Supersonic Blast Tube. Testing was performed in each test bed on two variants of the final two candidate materials. The
materials were a standard prewoven Lyocell, a postwoven Lyocell, an Enka rayon, and Enka rayon processed at a higher
carbonization temperature. This paper presents the results of the four materials in the SSBT and the SRTM tests as compared
against the NARC baseline. Erosion, char, and plylift results are discussed in detail.
Author
Ablative Materials; Impingement; Solid Propellant Rocket Engines; Supersonic Speed; Particles; Nozzle Design
20040073432 NASA Glenn Research Center, Cleveland, OH, USA
Overview of NASA GRC Stirling Technology Development
Schreiber, Jeffrey G.; Thieme, Lanny G.; May 2004; 16 pp.; In English; First International Energy Conversion Engineering
Conference, 17-21 Aug. 2003, Portsmouth, VA, USA
Report No.(s): NASA/TM-2004-212969; AIAA Paper 2003-6093; E-14442; No Copyright; Avail: CASI; A03, Hardcopy
The Stirling Radioisotope Generator (SRG) is currently being developed by Lockheed Martin Astronautics (LMA) under
contract to the Department of Energy (DOE). The generator will be a high efficiency electric power source for NASA Space
31