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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 433 records · Page 24
All sourcesNASA NTRSDOE OSTI
NASA NTRS2013

Methane Post-Processor Development to Increase Oxygen Recovery beyond State-of-the-Art Carbon Dioxide Reduction Technology

State‐of‐the‐art life support carbon dioxide (CO2) reduction technology, based on the Sabatier reaction, is theoretically capable of 50% recovery of oxygen from metabolic CO2. This recovery is constrained by the limited availability of reactant hydrogen. Post‐processing of the methane byproduct from the Sabatier reactor results in hydrogen recycle and a subsequent increase in oxygen recovery. For this purpose, a Methane Post‐Processor Assembly containing three sub‐systems has been developed and tested. The assembly includes a Methane Purification Assembly (MePA) to remove residual CO2 and water vapor from the Sabatier product stream, a Plasma Pyrolysis Assembly (PPA) to partially pyrolyze methane into hydrogen and acetylene, and an Acetylene Separation Assembly (ASepA) to purify the hydrogen product for recycle. The results of partially integrated testing of the sub‐systems are reported.

Abney, Morgan↗
NASA NTRS2013

Methane Post-Processor Development to Increase Oxygen Recovery beyond State-of-the-Art Carbon Dioxide Reduction Technology

State-of‐the‐art life support carbon dioxide (CO2) reduction technology, based on the Sabatier reaction, is theoretically capable of 50% recovery of oxygen from metabolic CO2. This recovery is constrained by the limited availability of reactant hydrogen. Post‐processing of the methane byproduct from the Sabatier reactor results in hydrogen recycle and a subsequent increase in oxygen recovery. For this purpose, a Methane Post‐Processor Assembly containing three sub‐systems has been developed and tested. The assembly includes a Methane Purification Assembly (MePA) to remove residual CO2 and water vapor from the Sabatier product stream, a Plasma Pyrolysis Assembly (PPA) to partially pyrolyze methane into hydrogen and acetylene, and an Acetylene Separation Assembly (ASepA) to purify the hydrogen product for recycle. The results of partially integrated testing of the sub‐systems are reported

Abney, Morgan B.↗
NASA NTRS2014

IVGEN Post Flight Analysis

The Intravenous Fluid Generation (IVGEN) Experiment was a technology demonstration experiment that purified ISS potable water, mixed it with salt, and transferred it through a sterilizing filter. On-orbit performance was verified as appropriate and two 1.5 l bags of normal saline solution were returned to earth for post-flight testing by a FDA certified laboratory for compliance with United States Pharmacopiea (USP) standards. Salt concentration deviated from required values and an analysis identified probable causes. Current efforts are focused on Total Organic Content (TOC) testing, and shelf life.The Intravenous Fluid Generation (IVGEN) Experiment demonstrated the purification of ISS potable water, the mixing of the purified water with sodium chloride, and sterilization of the solution via membrane filtration. On-orbit performance was monitored where feasible and two 1.5-liter bags of normal saline solution were returned to earth for post-flight testing by a FDA-registered laboratory for compliance with United States Pharmacopeia (USP)standards [1]. Current efforts have been focused on challenge testing with identified [2] impurities (total organic-carbon), and shelf life testing. The challenge testing flowed known concentrations of contaminants through the IVGEN deionizing cartridge and membrane filters to test their effectiveness. One finding was that the filters and DI-resin themselves contribute to the contaminant load during initial startup, suggesting that the first 100 ml of fluid be discarded. Shelf life testing is ongoing and involves periodic testing of stored DI cartridges and membrane filters that are capped and sealed in hermetic packages. The testing is conducted at six month intervals measuring conductivity and endotoxins in the effluent. Currently, the packaging technique has been successfully demonstrated for one year of storage testing. The USP standards specifies that the TOC be conducted at point of generation as opposed to point of consumption. Samples were generated and shipped to an FDA facility however, testing determined that the samples failed the TOC specification with most likely due to leaching from the sample container. Shelf life testing is examining packaging techniques and periodic testing of samples of DI cartridges that are capped and sealed in hermetic packages. Periodic testing of the purified water output will be conducted at six month intervals.

microgravity applications↗
NASA NTRS2014

Post-Flight Test Results of Acousto-Optic Modulator Devices Subjected to Space Exposure

The objective of the Materials International Space Station Experiment (MISSE) is to study the performance of novel materials when subjected to the synergistic effects of the harsh space environment for several months. MISSE missions provide an opportunity for developing space qualifiable materials. Several laser and lidar components were sent by NASA Langley Research Center (LaRC) as a part of the MISSE 7 mission. The MISSE 7 module was transported to the international space station (ISS) via STS 129 mission that was launched on Nov 16, 2009. Later, the MISSE 7 module was brought back to the earth via the STS 134 that landed on June 1, 2011. The MISSE 7 module that was subjected to exposure in a space environment for more than one and a half years included fiber laser, solid-state laser gain materials, detectors, and semiconductor laser diode. Performance testing of these components is now progressing. In this paper, the results of performance testing of a laser diode module sent by NASA Langley Research Center on MISSE 7 mission will be discussed. This paper will present the comparison of pre-flight and post-flight performance of two different COTS acousto-optic modulator (AOM) devices. Post-flight measurements indicate that these two devices did not undergo any significant performance degradation.

Prasad, Narasimha S.↗
NASA NTRS2001

Developing Sensorimotor Countermeasures to Mitigate Post-Flight Locomotor Dysfunction

Following spaceflight, crewmembers experience postural and locomotor instability. The magnitude and duration of post-flight sensorimotor disturbances increase with longer duration exposure to microgravity. These post-flight postural and locomotor alterations can pose a risk to crew safety and to mission objectives if nominal or emergency vehicle egress is required immediately following long-duration spaceflight. Gait instabilities could prevent or extend the time required to make an emergency egress from the Orbiter, Crew Return Vehicle or a future Martian lander leading to compromised mission objectives. We propose a countermeasure that aids in maintaining functional locomotor performance. This includes retaining the ability to perform vehicular egress and meet early mission objectives soon after landing on a planetary surface.

Bloomberg, J. J.↗
NASA NTRS2016

The Orion Exploration Flight Test Post Flight Solid Particle Flight Environment Inspection and Analysis

Orbital debris in the millimeter size range can pose a hazard to current and planned spacecraft due to the high relative impact speeds in Earth orbit. Fortunately, orbital debris has a relatively short life at lower altitudes due to atmospheric effects; however, at higher altitudes orbital debris can survive much longer and has resulted in a band of high flux around 700 to 1,500 km above the surface of the Earth. While large orbital debris objects are tracked via ground based observation, little information can be gathered about small particles except by returned surfaces, which until the Orion Exploration Flight Test number one (EFT-1), has only been possible for lower altitudes (400 to 500 km). The EFT-1 crew module backshell, which used a porous, ceramic tile system with surface coatings, has been inspected post-flight for potential micrometeoroid and orbital debris (MMOD) damage. This paper describes the pre- and post-flight activities of inspection, identification and analysis of six candidate MMOD impact craters from the EFT-1 mission.

Miller, Joshua E.↗
NASA NTRS2016

Post Launch Calibration and Testing of the Advanced Baseline Imager on the GOES-R Satellite

The Geostationary Operational Environmental Satellite R (GOES-R) series is the planned next generation of operational weather satellites for the United State's National Oceanic and Atmospheric Administration. The first launch of the GOES-R series is planned for October 2016. The GOES-R series satellites and instruments are being developed by the National Aeronautics and Space Administration (NASA). One of the key instruments on the GOES-R series is the Advance Baseline Imager (ABI). The ABI is a multi-channel, visible through infrared, passive imaging radiometer. The ABI will provide moderate spatial and spectral resolution at high temporal and radiometric resolution to accurately monitor rapidly changing weather. Initial on-orbit calibration and performance characterization is crucial to establishing baseline used to maintain performance throughout mission life. A series of tests has been planned to establish the post launch performance and establish the parameters needed to process the data in the Ground Processing Algorithm. The large number of detectors for each channel required to provide the needed temporal coverage presents unique challenges for accurately calibrating ABI and minimizing striping. This paper discusses the planned tests to be performed on ABI over the six-month Post Launch Test period and the expected performance as it relates to ground tests.

Instrument↗
NASA NTRS2016

Post Launch Calibration and Testing of the Geostationary Lightning Mapper on GOES-R Satellite

The Geostationary Operational Environmental Satellite R (GOES-R) series is the planned next generation of operational weather satellites for the United States National Oceanic and Atmospheric Administration (NOAA). The National Aeronautics and Space Administration (NASA) is procuring the GOES-R spacecraft and instruments with the first launch of the GOES-R series planned for October 2016. Included in the GOES-R Instrument suite is the Geostationary Lightning Mapper (GLM). GLM is a single-channel, near-infrared optical detector that can sense extremely brief (800 s) transient changes in the atmosphere, indicating the presence of lightning. GLM will measure total lightning activity continuously over the Americas and adjacent ocean regions with near-uniform spatial resolution of approximately 10 km. Due to its large CCD (1372x1300 pixels), high frame rate, sensitivity and onboard event filtering, GLM will require extensive post launch characterization and calibration. Daytime and nighttime images will be used to characterize both image quality criteria inherent to GLM as a space-based optic system (focus, stray light, crosstalk, solar glint) and programmable image processing criteria (dark offsets, gain, noise, linearity, dynamic range). In addition ground data filtering will be adjusted based on lightning-specific phenomenology (coherence) to isolate real from false transients with their own characteristics. These parameters will be updated, as needed, on orbit in an iterative process guided by pre-launch testing. This paper discusses the planned tests to be performed on GLM over the six-month Post Launch Test period to optimize and demonstrate GLM performance.

validation↗
NASA NTRS2016

Post Launch Calibration and Testing of the Geostationary Lightning Mapper on the GOES-R Satellite

The Geostationary Operational Environmental Satellite R (GOES-R) series is the planned next generation of operational weather satellites for the United States National Oceanic and Atmospheric Administration (NOAA). The National Aeronautics and Space Administration (NASA) is procuring the GOES-R spacecraft and instruments with the first launch of the GOES-R series planned for October 2016. Included in the GOES-R Instrument suite is the Geostationary Lightning Mapper (GLM). GLM is a single-channel, near-infrared optical detector that can sense extremely brief (800 microseconds) transient changes in the atmosphere, indicating the presence of lightning. GLM will measure total lightning activity continuously over the Americas and adjacent ocean regions with near-uniform spatial resolution of approximately 10 km. Due to its large CCD (1372x1300 pixels), high frame rate, sensitivity and onboard event filtering, GLM will require extensive post launch characterization and calibration. Daytime and nighttime images will be used to characterize both image quality criteria inherent to GLM as a space-based optic system (focus, stray light, crosstalk, solar glint) and programmable image processing criteria (dark offsets, gain, noise, linearity, dynamic range). In addition ground data filtering will be adjusted based on lightning-specific phenomenology (coherence) to isolate real from false transients with their own characteristics. These parameters will be updated, as needed, on orbit in an iterative process guided by pre-launch testing. This paper discusses the planned tests to be performed on GLM over the six-month Post Launch Test period to optimize and demonstrate GLM performance.

validation↗
NASA NTRS2016

Post Launch Calibration and Testing of the Advanced Baseline Imager on the GOES-R Satellite

The Geostationary Operational Environmental Satellite R (GOES-R) series is the planned next generation of operational weather satellites for the United States National Oceanic and Atmospheric Administration. The first launch of the GOES-R series is planned for October 2016. The GOES-R series satellites and instruments are being developed by the National Aeronautics and Space Administration (NASA). One of the key instruments on the GOES-R series is the Advance Baseline Imager (ABI). The ABI is a multi-channel, visible through infrared, passive imaging radiometer. The ABI will provide moderate spatial and spectral resolution at high temporal and radiometric resolution to accurately monitor rapidly changing weather. Initial on-orbit calibration and performance characterization is crucial to establishing baseline used to maintain performance throughout mission life. A series of tests has been planned to establish the post launch performance and establish the parameters needed to process the data in the Ground Processing Algorithm. The large number of detectors for each channel required to provide the needed temporal coverage presents unique challenges for accurately calibrating ABI and minimizing striping. This paper discusses the planned tests to be performed on ABI over the six-month Post Launch Test period and the expected performance as it relates to ground tests.

Instrument↗
NASA NTRS2016

Post-Buckling Analysis of Curved Honeycomb Sandwich Panels Containing Interfacial Disbonds

A numerical study on the effect of facesheet-core disbonds on the post-buckling response of curved honeycomb sandwich panels is presented herein. This work was conducted as part of the development of a damage tolerance plan for the next-generation Space Launch System heavy lift launch vehicle payload fairing. As such, the study utilized full-scale fairing barrel segments as the structure of interest. The panels were composed of carbon fiber reinforced polymer facesheets and aluminum honeycomb core. The panels were analyzed numerically using the finite element method incorporating geometric nonlinearity. In a predetermined circular region, facesheet and core nodes were detached to simulate a disbond, between the outer mold line facesheet and honeycomb core, induced via low-speed impact. Surface-to-surface contact in the disbonded region was invoked to prevent interpenetration of the facesheet and core elements and obtain realistic stresses in the core. The diameter of this disbonded region was varied and the effect of the size of the disbond on the post-buckling response was observed. Significant changes in the slope of the edge load-deflection response were used to determine the onset of global buckling and corresponding buckling load. Finally, several studies were conducted to determine the sensitivity of the numerical predictions to refinement in the finite element mesh.

elastic buckling↗
NASA NTRS2016

Small Business Innovation Research GRC Phase I, Phase II, and Post-Phase II Opportunity Assessment for 2015

This report outlines the 2015 Small Business Innovation Research/Small Business Technology Transfer (SBIR/STTR) Phase I, Phase II, and Post-Phase II opportunity contract award results associated with NASA's Aeronautics Research Mission Directorate (ARMD), Human Exploration and Operations Mission Directorate (HEOMD), Science Mission Directorate (SMD), and Space Technology Mission Directorate (STMD) for NASA Glenn Research Center. The report also highlights the number of Phase I, Phase II, and Post-Phase II contracts awarded by mission directorate. The 2015 Phase I contract awards to companies in Ohio and their corresponding technologies are also discussed.

Aeronautics Research ARMD↗
NASA NTRS2016

Post-Test Inspection of NASA's Evolutionary Xenon Thruster Long-Duration Test Hardware: Discharge and Neutralizer Cathodes

The NEXT Long-Duration Test is part of a comprehensive thruster service life assessment intended to demonstrate overall throughput capability, validate service life models, quantify wear rates as a function of time and operating condition, and identify any unknown life-limiting mechanisms. The test was voluntarily terminated in April 2014 after demonstrating 51,184 hours of high-voltage operation, 918 kg of propellant throughput, and 35.5 MN-s of total impulse. The post-test inspection of the thruster hardware began shortly afterwards with a combination of non-destructive and destructive analysis techniques, and is presently nearing completion. This presentation presents relevant results of the post-test inspection for both discharge and neutralizer cathodes.

Lifetime↗
NASA NTRS2018

Differences in Pre and Post Vascular Patterning Within Retinas from ISS Crew Members and Head-Down Tilt (HDT) Subjects by VESGEN Analysis

Accelerated research by NASA has investigated the significant risks incurred during long-duration missions in microgravity for Space Flight-Associated Neuro-ocular Syndrome (SANS, formerly known as Visual Impairments associated with Increased Intracranial Pressure, VIIP) [1]. For our study, NASA's VESsel GENeration Analysis (VESGEN) was used to investigate the role of retinal blood vessels in the etiology of SANS/VIIP. The response of retinal vessels to microgravity was evaluated in astronaut crew members pre and post flight to the International Space Station (ISS), and compared to the response of retinal vessels in healthy volunteers to 6deg head-down tilt during 70 days of bed rest (HDTBR). For the study, we are testing the hypothesis that long-term cephalad fluid shifts resulting in ocular and visual impairments are necessarily mediated in part by retinal blood vessels, and therefore are accompanied by structural adaptations of the vessels. METHODS: Vascular patterns in the retinas of crew members and HDTBR subjects extracted from 30deg infrared (IR) Heidelberg Spectralis images collected pre/postflight and pre/post HDTBR, respectively, were analyzed by VESGEN (patent pending). VESGEN is a mature, automated software developed as a research discovery tool for progressive vascular diseases in the retina and other tissues. The multi-parametric VESGEN analysis generates maps of branching arterial and venous trees quantified by parameters such as the fractal dimension (Df, a modern measure of vascular space-filling capacity), vessel diameters, and densities of vessel length and number classified into specific branching generations according to vascular physiological branching rules. The retrospective study approved by NASA's Institutional Review Board included the analysis of bilateral retinas in eight ISS crew members monitored by routine occupational surveillance and six HDTBR subjects (NASA FARU Campaign 11, for example). The VESGEN analysis was conducted in a blinded fashion, with IR retinal images masked to the subject's identity, ophthalmic and clinical characteristics, and to the temporal sequence of image collection. To complete our study, VESGEN results will be analyzed statistically and correlated with other ophthalmic and medical findings. RESULTS: Preliminary results for changes in the pre to post status of vascular patterning in the retinas of crew members and HDTBR subjects are interestingly opposite. By Df and other vascular branching measures, the space-filling capacity of arterial and venous trees decreased in the majority of crew members (11/16 retinas). In contrast, vascular densities increased in HDTBR subjects by the same parameters (6/10 retinas). To conclude the study, biostatistics and medical analyses will be conducted to quantify and draw conclusions about how the changes associated with flight compare to those associated with HDTBR. CONCLUSIONS: Vascular densities appeared to decrease in the retinas of ISS crew members and increase in HDTBR subjects. Differences in arterial and venous response to cephalad fluid shifts induced by ISS and HDTBR may have resulted from a long-duration conditioning phenomenon (for example, 6-month ISS missions compared to 70 days HDTBR), or the presence of gravity in HDTBR compared to microgravity on the ISS. In addition, increased and decreased vessel diameters for Crew Members and HDTBR, respectively, are subject to limits of im

Vascular↗
NASA NTRS2018

Post-Formation Sodium Loss on the Moon: A Bulk Estimate

The Moon and Earth are generally similar in terms of composition, but there exist variations in the abundance of certain elements among the two bodies. These differences are a likely consequence of differing physical evolution of the two bodies over the solar system's history. While previous works have assumed this may be due to conditions during the Moonâ€"TM"s formation, we explore the likelihood that the observed depletion in Sodium in lunar samples may be partially due to post-formation mechanisms. Solar effects, loss from a primordial atmosphere and impacts are some of the dominant post-formation mechanisms that we examine. We describe how our past and current modeling efforts indicate that a significant fraction of the observed depletion of sodium in lunar samples relative to a bulk silicate earth composition may have been due to solar activity, atmospheric loss and impacts. Using profiles of sodium abundances from lunar crustal samples may thus serve as a powerful tool towards exploring conditions on the Moon's surface throughout solar system history. Conditions on the Moon immediately after formation may still be recorded in the lunar crust and may provide a window towards interpreting observations from some of the first rocky exoplanets that will be most amenable to characterization. Potential spatial variation of sodium in the lunar crust may be a relevant consideration for future sample return efforts. Sodium Depletion in the Lunar Crust: Lunar

Solar↗
NASA NTRS2018

Post-Flight Data Analysis Tool

A software tool that facilitates the retrieval and analysis of post-flight data. This allows our team and other teams to effectively and efficiently analyze and evaluate post-flight data in order to certify commercial providers.

George, Marina↗
NASA NTRS2018

Systems and Methods for Post-Treatment of Dry Adhesive Microstructures

Provided are systems and methods for the post-treatment of dry adhesive microstructures. The microstructures may be post-treated to comprise mushroom-like flaps at their tips to interface with the contact surface. In some aspects, a change in material composition of the microstructures in a dry adhesive may affect mechanical properties to enhance or diminish overall adhesive performance. For example, conductive additives can be added to the material to improve adhesive performance. In other aspects, microstructures comprising conductive material may allow for pre-load engagement sensing systems to be integrated into the microstructures.

Dadkhah Tehrani, Mohammad↗
NASA NTRS2018

Musculoskeletal Injuries in US Astronauts: Injury Prevention Strategies, Including Pre-Flight EVA Fitness Training, Return to Flight Following Injuries, and Post-Flight Reconditioning

Outline: Background; Terrestrial experience -Initial investigation into MSK (MusculoSKeletal) injuries -MSK Medicine Program -Training injuries -NBL (Neutral Buoyancy Laboratory) EMU (Extravehicular activity Mobility Unit) Work Hardening Program -Return to duty -Post-flight reconditioning program; Inflight musculoskeletal conditions; Lunar Surface Operations; Post-flight injuries.

Scheuring, Richard A.↗