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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Nickel hydrogen low Earth orbit test program update and status

The current status of nickel-hydrogen (NiH2) testing ongong at NWSC, Crane In, and The Aerospace Corporation, El Segundo, Ca are described. The objective of this testing is to develop a database for NiH2 battery use in Low Earth Orbit (LEO) and support applications in Medium Altitude Orbit (MAO). Individual pressure vessel-type cells are being tested. A minimum of 200 cells (3.5 in diameter and 4.5 in diameter) are included in the test, from four U.S. vendors. As of this date (Nov. 18, 1986) approximately 60 cells have completed preliminary testing (acceptance, characterization, and environmental testing) and have gone into life cycling.

Badcock, C. C.↗
NASA NTRS1987

Advanced planar array development for space station

The results of the Advanced Planar Array Development for the Space Station contract are presented. The original objectives of the contract were: (1) to develop a process for manufacturing superstrate assemblies, (2) to demonstrate superstrate technology through fabrication and test, (3) to develop and analyze a preliminary solar array wing design, and (4) to fabricate a wing segment based on wing design. The primary tasks completed were designing test modules, fabricating, and testing them. LMSC performed three tasks which included thermal cycle testing for 2000 thermal cycles, thermal balance testing at the Boeing Environmental Test Lab in Kent, Washington, and acceptance testing a 15 ft x 50 in panel segment for 100 thermal cycles. The surperstrate modules performed well during both thermal cycle testing and thermal balance testing. The successful completion of these tests demonstrate the technical feasibility of a solar array power system utilizing superstrate technology. This final report describes the major elements of this contract including the manufacturing process used to fabricate modules, the tests performed, and the results and conclusions of the tests.

Source record↗
NASA NTRS1994

HYDRA, a new tool for mechanical testing

The introduction outlines the verification concept for programs of the European Space Agency (ESA). The role of the Agency in coordinating the activities of major European space test centers is summarized. Major test facilities of the environmental test center at ESTEC, the Space Research and Technology Center of ESA, are shown and their specific characteristics are highlighted with special emphasis on the 6-degree-of-freedom (6-DOF) hydraulic shaker. The specified performance characteristics for sine and transient tests are presented. Results of single-axis hardware tests and 6-DOF computer simulations are included. Efforts employed to protect payloads against accidental damage in case of malfunctions of the facility are listed. Finally the operational advantages of the facility, as well as the possible use of the HYDRA control system design for future applications are indicated.

Brinkmann, P. W.↗
NASA NTRS2001

Space Environmental Effects Testing and Characterization of the Candidate Solar Sail Material Aluminized Mylar

The usage of solar sails as a propellantless propulsion system has been proposed for many years. The technical challenges associated with solar sails are fabrication of ultralightweight films, deploying the sails and controlling the spacecraft. Integral to all these challenges is the mechanical property integrity of the sail while exposed to the harsh environment of space. This paper describes testing and characterization of a candidate solar sail material, Aluminized Mylar. This material was exposed to a simulated Geosynchronous Transfer Orbit (GTO) and evaluated by measuring thermooptical and mechanical property changes. Testing procedures and results are presented.

Edwards, D. L.↗
NASA NTRS2001

CM-2 Environmental / Modal Testing of Spacehab Racks

Combined environmental/modal vibration testing has been implemented at the NASA Glenn Research Center's Structural Dynamics Laboratory. The benefits of combined vibration testing are that it facilitates test article modal characterization and vibration qualification testing. The Combustion Module-2 (CM-2) is a space experiment that launches on Shuttle mission STS 107 in the SPACEHAB Research Double Module. The CM-2 flight hardware is integrated into a SPACEHAB single and double rack. CM-2 rack level combined vibration testing was recently completed on a shaker table to characterize the structure's modal response and verify the random vibration response. Control accelerometers and limit force gauges, located between the fixture and rack interface, were used to verify the input excitation. Results of the testing were used to verify the loads and environments for flight on the Shuttle.

McNelis, Mark E.↗
NASA NTRS2010

Environmental Stress Testing of the Single Sample Cylinder: A Proven Consensus Standard for Internal Gas Analysis (IGA) or Residual Gas Analysis (RGA)

In August 2008, Schuessler Consulting was contracted by NASA GSFC in support of the NASA Electronic Parts and Packaging (NEPP) program to perform two separate studies on moisture laden air in a stainless steel cylinder that had been designed to become a consensus standard for Test Method 1018. This Test Method was originally released for hybrids under Mil. Std. 883 but was quickly utilized on other microelectronic devices under the auspice of Mil. Std. 750. The cylinder had subsequently been fabricated for the 750 community. It was back-filled with moist air and subsequently analyzed over a period of time under a previous NASA contract. It had been shown that moisture in the 4000 - 5000 ppm range could be analyzed rather precisely with a mass spectrometer, commonly referred to as a Residual Gas Analyzer (RGA). The scope of this study was to ascertain if the composition and precision varied as a function of thermal shock at sub-zero temperatures and whether there was consensus when the standard was submitted to other RGA units. It was demonstrated and published that the consensus standard would yield precise RGA data for moisture within +/- 1% when optimized for a given RGA unit. It has been subsequently shown in this study at Oneida Research Services, that sub-zero storage did not affect that precision when a well-defined protocol for the analysis was followed. The consensus standard was taken to a second facility for analysis where it was found that moisture adsorption on the transfer lines caused precision to drop to +/- 12%. The Single Sample Cylinder (SSC) is a one liter stainless steel cylinder with associated sampling valves and has considerable weight and volume. But this considerable size allows for approximately 300 gas samples of the same composition to be delivered to any RGA unit. Lastly, a smaller cylinder, approximately 75 cc, of a second consensus standard was fabricated and tested with a different mix of fixed gases where moisture was kept in the 100 ppm range. This second standard has the potential of providing 30 gaseous samples and can be readily shipped to any analytical facility that desires to generate comparison RGA data. A series of comparison residual gas analyses was performed at the Honeywell Federal Manufacturing & Technologies facility in the National Nuclear Facility Administration s plant in Kansas City to complete this project. It was shown that improvements in the precision of a given RGA unit can be done by controlling the cycle time for each analysis and increasing analysis temperatures to minimize moisture adsorption. It was also found that a "one time event" in the subzero storage of the large SSC did not effect the units ability to continuously supply precise samples of the same chemistry, however the "event" caused a permanent +8% shift in the reported value of the moisture content. Lastly, a set of SSC RGA results was plotted on a common graph with DSCC "correlation study" RGA data. The result demonstrates the ability of the SSC to remove many of the individual variances that single, individual samples introduce. The consensus standards are now in storage at Oneida Research Services, one of the DSCC certified houses that does RGA to Military Standards, where they await future studies. The analytical data and the operational parameters of the instruments used are provided in the following discussion. Limitations and suggested means for improvement of both precision and accuracy are provided.

Schuessler, Philipp WH↗
NASA NTRS2010

iLIDS Simulations and Videos for Docking TIM

The video shows various aspects of the International Low Impact Docking System, including team members, some production, configuration, mated androgynous iLIDS, SCS Lockdown system, thermal analysis, electrical engineering aspects, the iLIDS control box and emulator, radiation testing at BNL, component environmental testing, component vibration testing, 3G processor board delivery system, GTA vibe test, EMA testbed, hook and hook disassembly, flex shaftdrive assembly, GSE cradle MISSE-6 Columbus, MISSE 6 and 7 seal experiments, actuated full scale seal test rig, LIDS on Hubble, dynamics test prep, EDU 54 mass emulation and SCS, load ring characterization, 6DOF proof test, SCS at 6DOF, machining EEMS and inner ring assembly, APAS assembly, inner ring fitting, rotation stand assembly, EEMS mating, and EEMS proof of concept demonstration.

Lewis, James L.↗
NASA NTRS2013

Large Scale Flame Spread Environmental Characterization Testing

Under the Advanced Exploration Systems (AES) Spacecraft Fire Safety Demonstration Project (SFSDP), as a risk mitigation activity in support of the development of a large-scale fire demonstration experiment in microgravity, flame-spread tests were conducted in normal gravity on thin, cellulose-based fuels in a sealed chamber. The primary objective of the tests was to measure pressure rise in a chamber as sample material, burning direction (upward/downward), total heat release, heat release rate, and heat loss mechanisms were varied between tests. A Design of Experiments (DOE) method was imposed to produce an array of tests from a fixed set of constraints and a coupled response model was developed. Supplementary tests were run without experimental design to additionally vary select parameters such as initial chamber pressure. The starting chamber pressure for each test was set below atmospheric to prevent chamber overpressure. Bottom ignition, or upward propagating burns, produced rapid acceleratory turbulent flame spread. Pressure rise in the chamber increases as the amount of fuel burned increases mainly because of the larger amount of heat generation and, to a much smaller extent, due to the increase in gaseous number of moles. Top ignition, or downward propagating burns, produced a steady flame spread with a very small flat flame across the burning edge. Steady-state pressure is achieved during downward flame spread as the pressure rises and plateaus. This indicates that the heat generation by the flame matches the heat loss to surroundings during the longer, slower downward burns. One heat loss mechanism included mounting a heat exchanger directly above the burning sample in the path of the plume to act as a heat sink and more efficiently dissipate the heat due to the combustion event. This proved an effective means for chamber overpressure mitigation for those tests producing the most total heat release and thusly was determined to be a feasible mitigation strategy to incorporate into the microgravity experiment.

Clayman, Lauren K.↗
NASA NTRSDate not supplied

Lunar Development & Test Facility, JSC B351

In anticipation of extended operations on the lunar sur-face, JSC Building B351 has been prepared to meet test needs to mature technologies that extract resources from lunar regolith, handle lunar regolith or must perform in a dusty lunar environment. Domains such as In-Situ Re-source Utilization (ISRU), dust mitigation, power generation and distribution, robotics and surface tools will all require testing with lunar regolith/simulants to demonstrate flight readiness. The Lunar Development and Test Facility (LDTF) houses environmental test capabilities, including lunar simulants, geared toward advancing Technical Readiness Level (TRL) of these lunar surface technologies. Seen as an agency need to enable and demonstrate new technologies, a portion of the facility capability was developed under the “Dirty Lunar Surface Simulation “project in FY2020, funded by the NASA Game Changing Development program. Some current uses include testing of an oxygen extraction from lunar regolith test, a spacesuit cleaning tool evaluation, and a study to measure dust effects on space radiators (thermal management).

Michael Reddington↗
NASA NTRS2023

Venus Surface Environmental Chamber Test of SiC JFET-R Multi-Chip Circuit Board

This poster describes a first attempt to demonstrate a multi-chip prototype lander control and sensor signal digitization electronics circuit board comprised of ten NASA Glenn IC Generation 11 SiC JFET-R IC chips in 460 °C, 9.4 MPa harsh Venus surface conditions. The lander circuit ceased electrical operation prematurely at 107 °C as the Venus chamber heated up. Optical and SEM post-test inspections indicate fatal dielectric cracks occurred on only one of the ten SiC chips.

silicon carbide↗
NASA NTRSDate not supplied

Solar Array System Combined Environmental Effects Tests: Gateway Power and Propulsion Element

The NASA Lunar Orbital Platform-Gateway (LOP-G), a vital component of NASA’s Artemis program, will serve as a multi-purpose outpost orbiting the Moon. A foundational component of LOP-G is the Power and Propulsion Element (PPE). The PPE is a high-power, +60-kilowatt solar electric propulsion spacecraft that will provide power, high-rate communications, attitude control, and orbital transfer capabilities for the Gateway. The solar array system will utilize 4-junction photovoltaic cell technology on a flexible substrate (roll-out solar array or ROSA) in combination with multiple diode assemblies to combine the power of the solar array strings. NASA’s Marshall Space Flight Center, together with the PPE developer, Maxar, are in the midst of completing a rigorous combined environments test campaign of 3 solar array coupons and 1 array blocking diode board coupon. The campaign includes Ultra-Violet Radiation, Charged Particle Radiation, Ion Erosion, Thermal Cycles, and Electrostatic Discharge tests. The environments are applied in 3 separate incremental stages reflecting the various mission phases: 460 days of Earth-to-Lunar Transit, with much of that time through the Van Allen Belts, 5-years in Lunar Near-Rectilinear Halo Orbit (NRHO) at the Moon, and finally 15-years in Lunar NRHO, which represents the end of the design life. This paper will report on the state of the testing for each coupon, and brief look at the array performance, including some unexpected sensitivities of array blocking diodes.

Gateway↗
NASA NTRSDate not supplied

NASA MSFC Lunar Surface Simulator (LSS): A Facility for Lunar Relevant Environment Testing

NASA will resume crewed visits to the lunar surface beginning in the mid-2020s. Environmental testing is essential to developing and validating the hardware that will enable a sustained presence on the lunar surface. Lunar dust is one of the most pressing challenges that threatens the longevity of mechanical systems as well as the health of astronauts living and working on the Moon. Facilities that allow large pieces of hardware to be exposed to both lunar dust and the temperature and vacuum of the lunar environment are invaluable to the agency as well as to the broader community of international, academic, and industry partners with which the agency collaborates. Marshall Space Flight Center has outfitted one of its largest thermal vacuum chambers with regolith simulant beds to create the Lunar Surface Simulator (LSS).

Relevant environment testing↗
NASA NTRSDate not supplied

NASA MSFC Lunar Surface Simulator (LSS): A Facility for Lunar Relevant Environment Testing

NASA will resume crewed visits to the lunar sur-face beginning in the mid-2020s. Environmental testing is essential to developing and validating the hardware that will enable a sustained presence on the lunar surface. Lunar dust is one of the most pressing challenges that threatens the longevity of mechanical systems as well as the health of astronauts living and working on the Moon. Facilities that allow large pieces of hard-ware to be exposed to both lunar dust and the temperature and vacuum of the lunar environment are invaluable to the agency as well as to the broader community of international, academic, and industry partners with which the agency collaborates. Marshall Space Flight Center has out-fitted one of its largest test chambers with regolith simulant beds to create the Lunar Surface Simulator (LSS).

Relevant environment testing↗
NASA NTRS2002

Relocation of the Cryo-Test Facility to NASA-MSFC

The Environmental Test Facility (ETF), located at NASA-Marshall Space Flight Center, Huntsville, Alabama, has provided thermal vacuum testing for several major programs since the 1960's. The ETF consists of over 13 thermal vacuum chambers sized and configured to handle the majority of test payloads. Testing is performed around the clock with multiple tests being conducted simultaneously. Chamber selection to achieve the best match with test articles and juggling program schedules, at times, can be a challenge. The ETF's Sunspot chamber has had tests scheduled and operated back-to-back for several years and provides the majority of schedule conflicts. Future test programs have been identified which surpass the current Sunspot availability. This paper describes a very low cost alternate to reduce schedule conflicts by utilizing government excess equipment

Sisco, Jimmy D.↗