NASA Scientific and Technical Aerospace Reports

20060002221 Idaho National Engineering Lab., Idaho Falls, ID, USA, Massachusetts Inst. of Tech., Cambridge, MA, USA,
California Univ., Davis, CA, USA
Predicting Ductile Crack Growth in Engineered Structures
Steffler, E. D.; McClintock, F. A.; Rashid, M. M.; Williamson, R. L.; Lloyd, Q. R.; Jan. 19, 2005; 38 pp.; In English
Report No.(s): DE2005-841394; No Copyright; Avail.: National Technical Information Service (NTIS)
The DOE Office of Science-Environmental Management Science Program (EMSP) conducted a High Level Waste
Workshop on January 19 and 20, 2005 at the Savannah River Site’s SREL Conference Center. The workshop was organized
to facilitate the exchange of information between university and national laboratory scientists and contractor and DOE
personnel from Idaho, Hanford, and Savannah River sites responsible for the management of high level waste. Following
overviews of the Savannah River, Hanford and Idaho high level waste programs and science and technology needs, principal
investigators (PI) for 27 projects reviewed findings and progress on their research programs focused on key science and
technology components of high level waste management. The workshop provided an excellent venue for the PI and site
operations personnel to develop contacts and facilitate communications which will advance the science and technology
resulting from these projects in a manner that will better address the needs of the HLW operations at each of the sites.
NTIS
Crack Propagation; Ductility; Predictions
20060002342 ISRO Satellite Centre, Peenya, Bangalore, India
Lifetime Enhancement of Sputtered MoS2 Film Lubricated Ball Bearings
Rao, A. Anna; Senthil Kumar, S. D. R.; Nagabushanam, S.; Journal of Spacecraft Technology, Volume 15, No. 2; July 2005,
pp. 1-9; In English; See also 20060002338; Copyright; Avail.: Other Sources
Sputtered MoS2 lubrication and well-proven ion plated lead lubrication are the basic techniques for applying dry
lubrication. Each process is selected based on the specific application, like definite lifetime, low torque noise and speed, Before
selecting the lubricant and its process, it is mandatory to look into the lifetime endurance history of the lubricant. Based on
individual experience, one can draw analogies for further decisions on the life assessment. We present the literature review
trends in of dry lubricants and their attainable endurance life and hypothetical estimates of sputtered MoS2 film lubrication
selected with other combinations for long life requirements of ball bearings for spacecraft scanner applications. Finally, we
describe the lifetime achieved with the combination of dry lubricants adapted at STL-ISAC which is 9x10(exp 8) cycles or
greater.
Author
Ball Bearings; Lubricants; Molybdenum Disulfides; Sputtering
20060002381 Marquette Univ., Milwaukee, WI, USA
Role of Distributed Inter-Bristle Friction Force On Brush Seal Hysteresis
Zhao, Helen; Stango, Robert; 2004 NASA Seal/Secondary Air System Workshop, Volume 1; October 2005, pp. 209-222; In
English; See also 20060002371; Original contains color illustrations; No Copyright; Avail.: CASI: A03, Hardcopy
The micro-moment can give rise to a delayed filament displacement as the shaft undergoes transient excursion and moves
radially toward bristle pack ( uploading). However, as the shaft returns back to its concentric position ( downloading), the
filament CANNOT completely recover from its deformed position and remains locked in an alternate configuration.
Consequently, an annular gap is generated between the fiber tips and shaft surface, which promotes brush seal leakage and
reduces turbomachinery performance.In general, for a given brush seal, the annular gap increases linearly as the micro moment
m* is increased. The brush seal having a shallowest lay angle (15deg) results in the smallest annular gap, indicating that a
brush seal design with shallow lay angle is least prone to hysteresis phenomenon, and can lead to improved performance.
Derived from text
Brush Seals; Leakage; Shafts (Machine Elements); Turbomachinery; Friction; Deformation
20060002405 Department of Energy, Las Vegas, NV, USA
Dry Transfer Facility Criticality Safety Calculations
Sanders, C. E.; May 2005; 84 pp.; In English
Report No.(s): DE2005-841275; No Copyright; Avail.: National Technical Information Service (NTIS)
This design calculation updates the previous criticality evaluation for the fuel handling, transfer, and staging operations
to be performed in the Dry Transfer Facility (DTF) including the remediation area. The purpose of the calculation is to
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