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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 343 records · Page 19
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

An overview of the Defence Research Agency photovoltaic programme

The Defense Research Agency (DRA) has been active in the photovoltaic field since the early 1960's, then as the Royal Aircraft Establishment (RAE). The early work was aimed at developing silicon cells, solar panels, and light-weight flexible arrays in support of the 'UK' and 'X' series of British scientific and technology satellites, for which the RAE was either the design authority or technical advisor. The X3 satellite - Prospero, launched in 1971 test flew 50 micron wrap-round silicon cells. The X4 satellite - Miranda, launched in 1974 test flew a deployable flexible silicon array which was developed at the DRA. During this period an extensive range of test equipment was developed which was maintained, modernized, and extended to date. Following a period of reduced activity in the late 1970's and early 1980's the current program evolved. The programs that have been undertaken since 1983 are briefly summarized. These range from various cell developments, new types of coverglasses, flight experiments, radiation testing, primary cell calibration, and environmental testing. The current photovoltaic program is mainly funded by the UK Ministry of Defence and by the Department of Trade and Industry through the British National Space Center (BNSC). The program is aimed at research and development, both internally and with industry, to meet the customer's technical objectives and requirements and to provide them with technical advice. The facilities are also being used on contract work for various national and international organizations.

Goodbody, C.↗
NASA NTRSDate not supplied

Navigation Doppler Lidar for Lunar Landers

The new generation of Navigation Doppler Lidar has been designed, developed, and tested for lunar missions. Comprehensive environmental testing is performed to assess the performance of the instrument for upcoming lunar missions and future missions to the Moon and other planetary bodies.

Lidar↗
NASA NTRSDate not supplied

Navigation Doppler Lidar for Lunar Landers

The new generation of Navigation Doppler Lidar has been designed, developed, and tested for lunar missions. Comprehensive environmental testing is performed to assess the performance of the instrument for upcoming lunar missions and future missions to the Moon and other planetary bodies.

Lidar↗
NASA NTRS1986

Long-term stability of amorphous-silicon modules

The Jet Propulsion Laboratory (JPL) program of developing qualification tests necessary for amorphous silicon modules, including appropriate accelerated environmental tests reveal degradation due to illumination. Data were given which showed the results of temperature-controlled field tests and accelerated tests in an environmental chamber.

Ross, R. G., Jr.↗
NASA NTRS1973

Extendible-retractable electric field measurement antenna for IMP J

An antenna dispenser mechanism for the IMP J spacecraft was designed, fabricated, and tested. Upon command the mechanism deploys or retracts a conductor for use as a receiving antenna for an electric field measurement experiment. Five identical units were fabricated and tested to the IMP H & J environmental test specification. Of these, four are designated for flight on the IMP J spacecraft and one as a prototype flight spare. The testing program was successfully completed although certain design modifications were required as problems were uncovered by the testing; particularly thermal vacuum operation. The antenna mechanism functions well under the expected environmental and loading conditions. The wear life and load capability of the dry molybdenum disulphide lubricant originally used on the heavily loaded worm and gear pair were disappointing and a substitute material was applied. The lubricant finally applied performed well; although other problems were generated.

Larrick, W.↗
NASA NTRS1965

Physical environment

Instrumentation for decompression chamber and other equipment used for environmental testing of chimpanzee - aerospace medicine

INSTRUMENTATION↗
NASA NTRS1978

Development of structural dynamic test environments for subsystems and components

Structural dynamic environmental test levels were developed for the thematic mapper instrument, components of the Tandberg-Hanssen instrument, and components of the International Ultraviolet Explorer spacecraft using NASTRAN structural models and test data. Both static and dynamic NASTRAN analyses were used. The model size required could be as small as 300 degrees of freedom for the static analysis and as large as 4000 degrees of freedom or more for the high frequency dynamic analysis. An important step in the development of the levels is model verification by test. The launch environments that generally dictate many important features of the design of an instrument or component are steady state acceleration, sinusoidal vibration, and random vibration.

Coladonato, R. J.↗
NASA NTRS2010

Evaluation of 3D Plus Packaging Test Structures for NASA Goddard Space Flight Center

Environmental tests were performed on packaging test structures designed and manufactured for ESA and CNES by 3D PLus ELectronics. The design provided circuit elements that acted as thermal, mechanical and moisture sensors. Other design features showed the compatibility of the packaging with chip passives, bare electronic dice and plastic encapsulated microcircuits packaged together in an innovative, stacked multichip module. The NASA GSFC testing augmented long duration testing on the same units carried out by ESA and CNES. The NASA portion demonstrated packaging stability over temperature, in moisture, with voltage stress, in shock and in vibration environments.

Plante, Jeannette↗
NASA NTRS1972

Study of acoustic emission during mechanical tests of large flight weight tank structure

A polyphenylane oxide insulated, flight weight, subscale, aluminum tank was monitored for acoustic emissions during a proof test and during 100 cycles of environmental test simulating space flights. The use of a combination of frequency filtering and appropriate spatial filtering to reduce background noise was found to be sufficient to detect acoustic emission signals of relatively small intensity expected from subcritical crack growth in the structure. Several emission source locations were identified, including the one where a flaw was detected by post-test X-ray inspections. For most source locations, however, post-test inspections did not detect flaws; this was partially attributed to the higher sensitivity of the acoustic emission technique than any other currently available NDT method for detecting flaws.

Nakamura, Y.↗
NASA NTRS1973

Study of acoustic emission during mechanical tests of large flight weight tank structure

A PPO-insulated, flight-weight, subscale, aluminum tank was monitored for acoustic emissions during a proof test and during 100 cycles of environmental test simulating space flights. The use of a combination of frequency filtering and appropriate spatial filtering to reduce background noise was found to be sufficient to detect acoustic emission signals of relatively small intensity expected from subcritical crack growth in the structure. Several emission source locations were identified, including the one where a flaw was detected by post-test x-ray inspections. For most source locations, however, post-test inspections did not detect flaws; this was partially attributed to the higher sensitivity of the acoustic emission technique than any other currently available NDT method for detecting flaws. For these non-verifiable emission sources, a problem still remains in correctly interpreting observed emission signals.

Mccauley, B. O.↗
NASA NTRS1985

Block 5 documentation and solar modules

Design and fabrication of Spire Corporation's Block 5 photovoltaic flat plate module is reviewed. These modules exhibited power of about 70 watts under standard test conditions. Results of performance and environmental testing are provided.

Source record↗
NASA NTRS1992

Creep fatigue life prediction for engine hot section materials (isotropic)

This Final Report covers the activities completed under the optional program of the NASA HOST Contract, NAS3-23288. The initial effort of the optional program was report-in NASA CR189221, which consisted of high temperature strain controlled fatigue tests to study the effects of thermomechanical fatigue, multiaxial loading, reactive environments, and imposed stresses. The baseline alloy used in the tests included B1900+Hf (with or without coating) and wrought INCO 718. Tests conducted on B1900+Hf included environmental tests using various atmospheres (75 psig oxygen, purified argon, or block exposures) and specimen tests of wrought INCO 718 included tensile, creep, stress rupture, TMF, multiaxial, and mean stress tests. Results of these testings were used to calibrate a CDA model for INCO 718 alloy and to develop modifications or corrections to the CDA model to handle additional failure mechanisms. The Socie parameter was found to provide the best correlation for INCO multiaxial loading. Microstructural evaluations consisting of optical, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM) techniques, and surface replication techniques to determine crack initiation lives provided data which were used to develop life prediction models.

Nelson, R. S.↗
NASA NTRS2007

Chemochromic Hydrogen Sensors

As fossil fuel supplies decline, hydrogen is quickly becoming an increasingly important fuel source. Currently hydrogen is the prime fuel of today's space vehicles (e.g., Space Shuttle) and featured as a fuel for some prototype vehicles such as the BMW seven series model. Hydrogen is a colorless, odorless gas with a 4% lower explosive limit which makes leak detection a priority. In an effort to support the use of hydrogen, a chemochromic (color changing) sensor was developed that is robust, simple to use, and does not require active operation. It can be made into a thin tape which can be conveniently used for leak detection at flanges, valves, or outlets. Chemochromic sensors can be either reversible or irreversible; however, irreversible chemochromic sensors will be analyzed in this report. The irreversible sensor is useful during hazardous operations when personnel cannot be present. To actively monitor leaks, testing of the irreversible sensor against environmental effects was completed and results indicated this material is suitable for outdoor use in the harsh beachside environment of Kennedy Space Center. The experiments in this report will give additional results to the environmental testing by adding solid rocket booster residue as a variable. The primary motivation for these experiments is to prepare the sensors for the launch pad environment at the Kennedy Space Center. In an effort to simulate the atmosphere at the pads before and after launch, the chemochromic sensors are exposed to solid rocket residue under various conditions.

Wiggins, Bryan C.↗
NASA NTRS2015

Thermal Coatings Seminar Series Training Part 1: Properties of Thermal Coatings

This course will present an overview of a variety of thermal coatings-related topics, including: coating types and availability, thermal properties measurements, environmental testing (lab and in-flight), environmental impacts, contamination impacts, contamination liabilities, determination of BOLEOL values, and what does specularity mean to the thermal engineer.

Triolo, Jack↗
NASA NTRS2015

Thermal Coatings Seminar Series Training Part 2: Environmental Effects

This course will present an overview of a variety of thermal coatings-related topics, including: coating types and availability, thermal properties measurements, environmental testing (lab and in-flight), environmental impacts, contamination impacts, contamination liabilities, determination of BOLEOL values, and what does specularity mean to the thermal engineer.

Triolo, Jack↗