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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 1,585 records · Page 88
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Forest Resource Information System. Phase 3: System transfer report

Transfer of the forest reserve information system (FRIS) from the Laboratory for Applications of Remote Sensing to St. Regis Paper Company is described. Modifications required for the transfer of the LARYS image processing software are discussed. The reformatting, geometric correction, image registration, and documentation performed for preprocessing transfer are described. Data turnaround was improved and geometrically corrected and ground-registered CCT LANDSAT 3 data provided to the user. The technology transfer activities are summarized. An application test performed in order to assess a Florida land acquisition is described. A benefit/cost analysis of FRIS is presented.

Mroczynski, R. P.↗
NASA NTRS1985

Mechanical testing of large thallium doped sodium iodide single crystals

The findings of mechanical tests performed on five thallium-doped sodium iodide NaI(Tl) crystals are presented. These crystals are all in the shape of circular flat plates, 20.0 in. in diameter an d0.5 in. thick. The test setup, testing procedure, and the test data are presented. Large crystals exhibit a high degree of material plasticity, as well as a much higher strength than previously anticipated, on the order of 500 psi. Also revealed from the testing is the fact that crystal with a large number of grain boundaries developed less plasticity, and therefore less permanent deformation, than those with fewer grain boundaries.

Lee, H. M.↗
NASA NTRS1989

20 kHz, 25 kVA node power transformer

The electrical and mechanical design information and the electrical and thermal testing performed on the 440-208-V rms, 20-kHz, 25-kVa prototype node transformer are summarized. The calculated efficiency of the node transformer is 99.3 percent based on core loss and copper loss test data, and its maximum calculated load regulation is 0.7 percent. The node transformer has a weight of 19.7 lb and has a power density of 0.8 lb/kW. The hot-spot temperature rise is estimated to be 33 C above the cold plate mounting base. This proof-of-concept transformer design is a viable candidate for the space station Freedom application.

Hussey, S.↗
NASA NTRS1991

Initial pointing calibrations for the DSS 13 34-meter beam-waveguide antenna

The beam pointing of the Deep Space Station (DSS) 13 beam-waveguide antenna at the Goldstone Venus site was calibrated during the postconstruction performance testing period from Jul. 1990 through Jan. 1991. The pointing calibrations were based on errors measured on radio sources at both the Cassegrain and centerline beam-waveguide focal points. The blind pointing performance goal of 5.0 mdeg, 3-sigma at Ka-band (32 GHz) was demonstrated to be met for low (less than 10 mph) wind conditions.

Alvarez, L. S.↗
NASA NTRS1991

NASA. Marshall Space Flight Center Hydrostatic Bearing Activities

The basic approach for analyzing hydrostatic bearing flows at the Marshall Space Flight Center (MSFC) is briefly discussed. The Hydrostatic Bearing Team has responsibility for assessing and evaluating flow codes; evaluating friction, ignition, and galling effects; evaluating wear; and performing tests. The Office of Aerospace and Exploration Technology Turbomachinery Seals Tasks consist of tests and analysis. The MSFC in-house analyses utilize one-dimensional bulk-flow codes. Computational fluid dynamics (CFD) analysis is used to enhance understanding of bearing flow physics or to perform parametric analysis that are outside the bulk flow database. As long as the bulk flow codes are accurate enough for most needs, they will be utilized accordingly and will be supported by CFD analysis on an as-needed basis.

Benjamin, Theodore G.↗
NASA NTRS2016

SEXTANT X-Ray Pulsar Navigation Demonstration: Flight System and Test Results

The Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) is a technology demonstration enhancement to the Neutron-star Interior Composition Explorer (NICER) mission. NICER is a NASA Explorer Mission of Opportunity that will be hosted on the International Space Station (ISS). SEXTANT will, for the first time, demonstrate real-time, on-board X-ray Pulsar Navigation (XNAV), a significant milestone in the quest to establish a GPS-like navigation capability available throughout our Solar System and beyond. This paper gives an overview of the SEXTANT system architecture and describes progress prior to environmental testing of the NICER flight instrument. It provides descriptions and development status of the SEXTANT flight software and ground system, as well as detailed description and results from the flight software functional and performance testing within the highfidelity Goddard Space Flight Center (GSFC) X-ray Navigation Laboratory Testbed (GXLT) software and hardware simulation environment. Hardware-in-the-loop simulation results are presented, using the engineering model of the NICER timing electronics and the GXLT pulsar simulator-the GXLT precisely controls NASA GSFC's unique Modulated X-ray Source to produce X-rays that make the NICER detector electronics appear as if they were aboard the ISS viewing a sequence of millisecond pulsars.

SEXTANT↗
NASA NTRS2016

SEXTANT X-Ray Pulsar Navigation Demonstration: Flight System and Test Results

The Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) is a technology demonstration enhancement to the Neutron-star Interior Composition Explorer (NICER) mission. NICER is a NASA Explorer Mission of Opportunity that will be hosted on the International Space Station (ISS). SEXTANT will, for the first time, demonstrate real-time, on-board X-ray Pulsar Navigation (XNAV), a significant milestone in the quest to establish a GPS-like navigation capability available throughout our Solar System and beyond. This paper gives an overview of the SEXTANT system architecture and describes progress prior to environmental testing of the NICER flight instrument. It provides descriptions and development status of the SEXTANT flight software and ground system, as well as detailed description and results from the flight software functional and performance testing within the high-fidelity Goddard Space Flight Center (GSFC) X-ray Navigation Laboratory Testbed (GXLT) software and hardware simulation environment. Hardware-in-the-loop simulation results are presented, using the engineering model of the NICER timing electronics and the GXLT pulsar simulator-the GXLT precisely controls NASA GSFC's unique Modulated X-ray Source to produce X-rays that make the NICER detector electronics appear as if they were aboard the ISS viewing a sequence of millisecond pulsars

Pulsar↗
NASA NTRS2018

Design Limit Loads and Verification Approach for the TESS Observatory

The Transiting Exoplanet Survey Satellite (TESS) is a NASA Explorer mission. The TESS Observatory is scheduled to launch on Falcon 9 in April 2018. This presentation covers the process used to define and update design limit loads for the observatory, instrument, and components throughout the life of the program. The limit loads that drove the need for a SoftRide isolation system are highlighted. The testing performed to qualify the observatory for launch loads at the instrument and observatory level is also detailed. In addition, exchanges with the launch vehicle provider in terms of loads predictions and hardware for test are discussed along with the associated issues encountered and lessons learned. The loads development and verification success on TESS was a team effort. Orbital ATK is the spacecraft provider, NASA GSFC provides project management and technical oversight, the instrument is managed by MIT Kavli Institute and the instrument cameras are built and tested by MIT Lincoln Laboratory. Since the instrument was designed in parallel with the spacecraft, the instrument design limit loads were developed in partnership with NASA and the instrument team. The three teams collaborated on a regular basis starting in the early design phase and continuing through observatory level testing.

Limit Loads↗
NASA NTRSDate not supplied

Update on Planetary, Lunar, & Asteroid Natural Environment Testbed (PLANET)

At ISMSE15, the Planetary, Lunar, & Asteroid Natural Environment Testbed (PLANET) was introduced as an upcoming high-fidelity, combined-effects planetary surface environment laboratory. This year, we will present an update on the facility status, describing the procurement, installation, commissioning of the chamber in Huntsville, Alabama (USA). With NASA’s push to return to the Moon through the Artemis program, there is a clear need for more high-fidelity test chambers that can replicate multiple aspects of the lunar surface, especially the fine, dusty lunar soil known as regolith. The PLANET chamber is designed to fill this gap, enabling research & development, qualification, and verification testing in a combined lunar surface environment, at an affordable price, for government, commercial/industry, and academic partners. Features include a large regolith simulant bed, low energy electron and ion sources to replicate the solar wind, full-spectrum UV and Solar simulation, and a liquid nitrogen cryogenic shroud, all in a high-vacuum environment (as low as 10^-7 mbar). PLANET’s initial focus will be on the lunar environment, but other surface environments (Martian, asteroid, etc.) are also possible to simulate. Besides the environmental instrumentation, PLANET will be equipped with specialized test systems that the Space Environmental Effects Team has developed over the past two years, including an in-situ tribometer and uniform dust distribution system. The chamber is currently being manufactured, with plans to install in May 2024. This will be followed by outfitting and commissioning. The challenges and accomplishments seen during this process will be detailed, and data from the first tests performed in PLANET will be shared with the community.

environmental testing↗
DOE OSTI2022

Salt Sampling FY21 Technical Report

The goal of the salt sampling program at Argonne is to develop and deploy automated molten salt sampling approaches to enable high-precision in-process salt sample analysis to improve the timeliness of sampling-based accountancy measurements. Tools currently under development in support of this goal include (1) a modular vacuum sampler with an accompanying sample handling method for coupling vacuum sampling with high-precision at-line sample analysis, (2) a pneumatic sample generator that enables high-throughput sample analysis to improve the precision of existing analytical techniques, and (3) a windowless flow cell to enable on-line optical analysis of molten salt in a sampling loop. Compared to point sampling approaches (i.e., dip probes), vacuum sampling systems and on-line sampling loops facilitate access to a larger cross-section of a process fluid. This is known to improve the characterization of the process fluid by producing more representative samples and by enabling the analysis of a larger cross section of the fluid. A vacuum sampling approach for molten salts eliminates the risk of dross contamination of samples and avoids the use of moving parts in the salt. In FY21, two methods for integrating a vacuum sampler with a pneumatic sample generator were tested. These included direct fluidic coupling and coupling using a solid salt transfer mechanism. Solid salt transfer was ultimately selected over fluidic coupling, primarily to enable the transport of samples over longer distances to support automated at-line integration with high-precision techniques (such as microcalorimetry) that cannot withstand the extreme conditions near an electrorefining process. To facilitate rapid solid salt coupling, new mechanisms were developed for rapidly charging and discharging salt sample tubes at the vacuum sampler and pneumatic sample generator, respectively. While the charging mechanism will be deployed in FY22, the tube transfer method and discharge mechanism were tested in FY21. These were deployed at one of Argonne’s engineering-scale electrorefiners to implement at-line high-throughput pneumatic micro-sample generation capabilities. The method was used to generate precise uranium- and lanthanide-bearing electrorefiner micro-samples with the specific dimensions requested by researchers at Los Alamos National Laboratory for use in testing their novel microcalorimeter x-ray techniques. The solid salt transfer mechanism proved not only to be an effective means of integrating the precision sample generator with vacuum sampling, but also improved the performance of the sampler generator. Because the modular sampling approach described here eliminates the need for new high-radiation sample handling capabilities, salt-wetted seals, salt-wetted moving parts, and heated transfer lines outside the electrorefiner, it will address most of the remaining technical challenges for the at-line deployment of high-precision analytical techniques. This will enable significant reductions in the time delay for sampling-based accountancy measurements by eliminating the need for manual off-line sample processing and analysis. On-line optical analysis of molten salt in a sampling loop would provide complementary information to at-line and in-situ techniques. In FY21, an open-aperture molten salt gravity flow cell with windowless optical access to flowing salt was successfully demonstrated. Future work should include the refinement and performance testing of the on-line and at-line sampling tools, integration of additional analysis techniques, stakeholder outreach and collaboration, evaluation of the integrated methods, and analyses to determine how the various tools might fit into an integrated safeguards monitoring system of unattended near real time monitoring tools.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
NASA NTRS1980

An assessment of the future roles of the National Transonic Facility and the Langley Transonic Dynamics Tunnel in aeroelastic and unsteady aerodynamic testing

The characteristics and capabilities of the two tunnels, that relate to studies in the fields of aeroelasticity and unsteady aerodynamics are discussed. Scaling considerations for aeroelasticity and unsteady aerodynamics testing in the two facilities are reviewed, and some of the special features (or lack thereof) of the Langley Research Center Transonic Dynamics Tunnel (TDT) and the National Transonic Facility (NTF) that will weigh heavily in any decisions conducting a given study in the two tunnels are discussed. For illustrative purposes a fighter and a transport airplane are scaled for tests in the NTF and in the TDT, and the resulting model characteristics are compared. The NTF was designed specifically to meet the need for higher Reynolds number capability for flow simulation in aerodynamic performance testing of aircraft designs. However, the NTF can be a valuable tool for evaluating the severity of Reynolds number effects in the areas of dynamic aeroelasticity and unsteady aerodynamics. On the other hand, the TDT was constructed specifically for studies and tests in the field of aeroelasticity. Except for tests requiring the Reynolds number capability of NTF, the TDT will remain the primary facility for tests of dynamic aeroelasticity and unsteady aerodynamics.

Hanson, P. W.↗
NASA NTRS1983

Long Duration Exposure Facility (LDEF) structural verification test report

Structural load tests on the Long Duration Exposure Facility's (LDEF) primary structure were conducted. These tests had three purposes: (1) demonstrate structural adequacy of the assembled LDEF primary structure when subjected to anticipated flight loads; (2) verify analytical models and methods used in loads and stress analysis; and (3) perform tests to comply with the Space Transportation System (STS) requirements. Test loads were based on predicted limit loads which consider all flight events. Good agreement is shown between predicted and observed load, strain, and deflection data. Test data show that the LDEF structure was subjected to 1.2 times limit load to meet the STS requirements. The structural adequacy of the LDEF is demonstrated.

Jones, T. C.↗
NASA NTRS1998

A Spaceflight Magnetic Bearing Equipped Optical Chopper with Six-Axis Active Control

This paper describes the development of an ETU (Engineering Test Unit) rotary optical chopper with magnetic bearings. An ETU is required to be both flight-like, nearly identical to a flight unit without the need for material certifications, and demonstrate structural and performance integrity. A prototype breadboard design previously demonstrated the feasibility of meeting flight performance requirements using magnetic bearings. The chopper mechanism is a critical component of the High Resolution Dynamics Limb Sounder (HIRDLS) which will be flown on EOS-CHEM (Earth Observing System-Chemistry). Particularly noteworthy are the science requirements which demand high precision positioning and minimal power consumption along with full redundancy of coils and sensors in a miniature, lightweight package. The magnetic bearings are unique in their pole design to minimize parasitic losses and utilize collocated optical sensing. The motor is of an unusual disk-type ironless stator design. The ETU design has evolved from the breadboard design. A number of improvements have been incorporated into the ETU design. Active thrust control has been added along with changes to improve sensor stability, motor efficiency, and touchdown and launch survivability. It was necessary to do all this while simultaneously reducing the mechanism volume. Flight-like electronics utilize a DSP (Digital Signal Processor) and contain all sensor electronics and drivers on a single five inch by nine inch circuit board. Performance test results are reported including magnetic bearing and motor rotational losses.

Blumenstock, Kenneth A.↗
NASA NTRS1998

A Spaceflight Magnetic Bearing Equipped Optical Chopper with Six-Axis Active Control

This paper describes the development of an ETU (Engineering Test Unit) rotary optical chopper with magnetic bearings. An ETU is required to be both flight-like, nearly identical to a flight unit without the need for material certifications, and demonstrate structural and performance integrity. A prototype breadboard design previously demonstrated the feasibility of meeting flight performance requirements using magnetic bearings. The chopper mechanism is a critical component of the High Resolution Dynamics Limb Sounder (HIRDLS) which will be flown on EOS-CHEM (Earth Observing System-Chemistry). Particularly noteworthy are the science requirements which demand high precision positioning and minimal power consumption along with full redundancy of coils and sensors in a miniature, lightweight package. The magnetic bearings are unique in their pole design to minimize parasitic losses and utilize collocated optical sensing. The motor is of an unusual disk-type ironless stator design. The ETU design has evolved from the breadboard design. A number of improvements have been incorporated into the ETU design. Active thrust control has been added along with changes to improve sensor stability, motor efficiency, and touchdown and launch survivability. It was necessary to do all this while simultaneously reducing the mechanism volume. Flight-like electronics utilize a DSP (Digital Signal Processor) and contain all sensor electronics and drivers on a single five inch by nine inch circuit board. Performance test results are reported including magnetic bearing and motor rotational losses.

Blumenstock, K. A.↗
NASA NTRS1998

A Spaceflight Magnetic Bearing Equipped Optical Chopper with Six-Axis Active Control

This paper describes the development of an ETU (Engineering Test Unit) rotary optical chopper with magnetic bearings. An ETU is required to be both flight-like, nearly identical to a flight unit without the need for material certifications, and demonstrate structural and performance integrity. A prototype breadboard design previously demonstrated the feasibility of meeting flight performance requirements using magnetic bearings. The chopper mechanism is a critical component of the High Resolution Dynamics Limb Sounder (HIRDLS) which will be flown on EOS-CHEM (Earth Observing System-Chemistry). Particularly noteworthy are the science requirements which demand high precision positioning and minimal power consumption along with full redundancy of coils and sensors in a miniature, lightweight package. The magnetic bearings are unique in their pole design to minimize parasitic losses and utilize collocated optical sensing. The motor is of an unusual disk-type ironless stator design. The ETU design has evolved from the breadboard design. A number of improvements have been incorporated into the ETU design. Active thrust control has been added along with changes to improve sensor stability, motor efficiency, and touchdown and launch survivability. It was necessary to do all this while simultaneously reducing the mechanism volume. Flight-like electronics utilize a DSP (Digital Signal Processor) and contain all sensor electronics and drivers on a single five inch by nine inch circuit board. Performance test results are reported including magnetic bearing and motor rotational losses.

Blumenstock, Kenneth A.↗
NASA NTRS2001

Validation of a High-Order Compact Code for Nonlinear Flows About Complex Geometric

The slides review computational requirements for nozzle exhaust flow and noise calculations and the current numerical method, validation of prefactored compact scheme on CAA benchmark problems, a curvilinear grid performance test of gust response of a Joukowski airfoil, airfoil surface RMS pressure distribution and far field noise radiation results for Joukowski airfoil in a vortical gust, boundary distance study for Joukowski airfoil problem, and performance of ICOMP parallel Macintosh cluster.

Hixon, Ray↗
NASA NTRS2015

NASA Glenn Icing Research Tunnel: 2014 and 2015 Cloud Calibration Procedures and Results

This report summarizes the current status of the NASA Glenn Research Center (GRC) Icing Research Tunnel cloud calibration: specifically, the cloud uniformity, liquid water content, and drop-size calibration results from both the January-February 2014 full cloud calibration and the January 2015 interim cloud calibration. Some aspects of the cloud have remained the same as what was reported for the 2014 full calibration, including the cloud uniformity from the Standard nozzles, the drop-size equations for Standard and Mod1 nozzles, and the liquid water content for large-drop conditions. Overall, the tests performed in January 2015 showed good repeatability to 2014, but there is new information to report as well. There have been minor updates to the Mod1 cloud uniformity on the north side of the test section. Also, successful testing with the OAP-230Y has allowed the IRT to re-expand its operating envelopes for large-drop conditions to a maximum median volumetric diameter of 270 microns. Lastly, improvements to the collection-efficiency correction for the SEA multi-wire have resulted in new calibration equations for Standard- and Mod1-nozzle liquid water content.

aircraft icing↗
NASA NTRSDate not supplied

Toward the fabrication of a 5 μm resolution Wolter microscope for the National Ignition Facility

Advancements in computer-controlled polishing, metrology, and replication have led to a x-ray mirror fabrication process that is capable of producing high-resolution Wolter microscopes. The mirror is a nickel-cobalt replicated full-shell mirror that was electroformed from a finely figured and polished mandrel. This mandrel was designed and fabricated for a 8 m source-to-detector distance microscope, with 10× magnification. A computer controlled polishing process corrected the low-frequency mandrel figure to < 2.0 nm RMS error. The mandrel design was optimized to reduce shell distortions that occur mainly < 20 mm from the shell ends. This design, in combination with improved replication tooling design and refined bath parameters informed by a detailed COMSOL model, have led to reductions in replication errors in the mirror shell. X-ray tests performed on a pair of mirror shells replicated from the mandrel have demonstrated < 10 μm FWHM source plane imaging resolution. Here we discuss the development process, highlight results from metrology and x-ray testing, and define a path for achieving 5 μm FWHM resolution.

Grazing Incidence, Wolter Microscope, X-ray Optics↗