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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 775 records · Page 43

All sources NASA NTRS DOE OSTI

NASA NTRS1990

Precipitation chemistry - Atmospheric loadings to the surface waters of the Indian River lagoon basin by rainfall

Rain volume and chemistry monitoring as part of the Kennedy Space Center Long Term Environmental Monitoring Program included the years 1984-1987 as part of the National Atmospheric Deposition Program. Atmospheric deposition in rainfall consisted primarily of sea salt and hydrogen ion, sulfate, nitrate, and ammonium ions. The deposition of nitrogen (a principal plant nutrient) was on the order of 200-300 metric tons per year to the surface waters.

Dreschel, Thomas W.↗

NASA NTRS1992

Metals production

Existing procedures for design of electrochemical plants can be used for design of lunar processes taking into consideration the differences in environmental conditions. These differences include: 1/6 Earth gravity, high vacuum, solar electrical and heat source, space radiation heat sink, long days and nights, and different availability and economics of materials, energy, and labor. Techniques have already been developed for operation of relatively small scale hydrogen-oxygen fuel cell systems used in the U.S. lunar landing program. Design and operation of lunar aqueous electrolytic process plants appears to be within the state-of-the-art. Finding or developing compatible materials for construction and designing of fused-magma metal winning cells will present a real engineering challenge.

Beck, Theodore S.↗

NASA NTRS1993

Recent testing of 30 KW hydrogen arcjet thrusters

NASA is conducting efforts to evaluate high-power hydrogen arcjets for orbit transfer propulsion applications. As part of this program, an attempt was made to reexamine both radiatively- and regeneratively-cooled, 30 kW thrusters first demonstrated by the Giannini Scientific Corp. in 1963. The arcjets were configured to force arc attachment upstream of the throat in a subsonic chamber region. While thruster currents were steady, the voltage traces exhibited sawtooth waveforms at frequencies on the order of 20 kHz. Voltage variations per cycle were typically between 100 and 310 volts, indicating major changes in the position of the arc attachment with time. When operated at their respective design points, the performance of both thrusters fell below the values listed in the 1960's development reports. The reason for the discrepancies is not currently understood and further investigations are in progress. However, the recently measured efficiencies were high compared to those obtained with constricted-arc designs at similar conditions, and further arcjet performance optimizations may be possible.

Haag, Thomas W.↗

NASA NTRS1993

Recent testing of 30 kW hydrogen arcjet thrusters

Haag, Thomas W.↗

NASA NTRS1997

Electrolysis Performance Improvement Concept Study (EPICS) Flight Experiment-Reflight

The Electrolysis Performance Improvement Concept Study (EPICS) is a flight experiment to demonstrate and validate in a microgravity environment the Static Feed Electrolyzer (SFE) concept which was selected for the use aboard the International Space Station (ISS) for oxygen (O2) generation. It also is to investigate the impact of microgravity on electrochemical cell performance. Electrochemical cells are important to the space program because they provide an efficient means of generating O2 and hydrogen (H2) in space. Oxygen and H2 are essential not only for the survival of humans in space but also for the efficient and economical operation of various space systems. Electrochemical cells can reduce the mass, volume and logistical penalties associated with resupply and storage by generating and/or consuming these gases in space. An initial flight of the EPICS was conducted aboard STS-69 from September 7 to 8, 1995. A temperature sensor characteristics shift and a missing line of software code resulted in only partial success of this initial flight. Based on the review and recommendations of a National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) review team a reflight activity was initiated to obtain the remaining desired results, not achieved during the initial flight.

Schubert, F. H.↗

NASA NTRS2015

TankSIM: A Cryogenic Tank Performance Prediction Program

Accurate prediction of the thermodynamic state of the cryogenic propellants in launch vehicle tanks is necessary for mission planning and successful execution. Cryogenic propellant storage and transfer in space environments requires that tank pressure be controlled. The pressure rise rate is determined by the complex interaction of external heat leak, fluid temperature stratification, and interfacial heat and mass transfer. If the required storage duration of a space mission is longer than the period in which the tank pressure reaches its allowable maximum, an appropriate pressure control method must be applied. Therefore, predictions of the pressurization rate and performance of pressure control techniques in cryogenic tanks are required for development of cryogenic fluid long-duration storage technology and planning of future space exploration missions. This paper describes an analytical tool, Tank System Integrated Model (TankSIM), which can be used for modeling pressure control and predicting the behavior of cryogenic propellant for long-term storage for future space missions. It is written in the FORTRAN 90 language and can be compiled with any Visual FORTRAN compiler. A thermodynamic vent system (TVS) is used to achieve tank pressure control. Utilizing TankSIM, the following processes can be modeled: tank self-pressurization, boiloff, ullage venting, and mixing. Details of the TankSIM program and comparisons of its predictions with test data for liquid hydrogen and liquid methane will be presented in the final paper.

Bolshinskiy, L. G.↗

NASA NTRS2017

Failure Mechanisms of Ni-H2 and Li-Ion Batteries Under Hypervelocity Impacts

Lithium-Ion (Li-Ion) batteries have yielded significant performance advantages for many industries, including the aerospace industry, and have been selected to replace nickel hydrogen (Ni-H2) batteries for the International Space Station (ISS) program to meet the energy storage demands. As the ISS uses its vast solar arrays to generate its power, the solar ar-rays meet their sunlit power demands and supply excess power to battery packs for power de-livery on the sun obscured phase of the approximate 90 minute low Earth orbit. These large battery packs are located on the exterior of the ISS, and as such, the battery packs are ex-posed to external environment threats like naturally occurring meteoroids and artificial orbital debris (MMOD). While the risks from these solid particle environments has been known and addressed to an acceptable risk of failure through shield design, it is not possible to completely eliminate the risk of loss of these assets on orbit due to MMOD, and as such, failure consequences to the ISS have been considered.

Miller, J. E.↗

NASA NTRS2017

Failure Mechanisms of Ni-H2 and Li-Ion Batteries Under Hypervelocity Impacts

Lithium-Ion (Li-Ion) batteries have yielded significant performance advantages for many industries, including the aerospace industry, and have been selected to replace nickel hydrogen (Ni-H2) batteries for the International Space Station (ISS) program to meet the energy storage demands. As the ISS uses its vast solar arrays to generate its power, the solar arrays meet their sunlit power demands and supply excess power to battery packs for power delivery on the sun obscured phase of the approximate 90 minute low Earth orbit. These large battery packs are located on the exterior of the ISS, and as such, the battery packs are exposed to external environment threats like naturally occurring meteoroids and artificial orbital debris (MMOD). While the risks from these solid particle environments has been known and addressed to an acceptable risk of failure through shield design, it is not possible to completely eliminate the risk of loss of these assets on orbit due to MMOD, and as such, failure consequences to the ISS have been considered.

Miller, J. E.↗

DOE OSTI2022

Plan for Scaling Up Hydrogen Production with Nuclear Power Plants

The United States (U.S.) Department of Energy’s (DOE’s) Light Water Reactor Sustainability (LWRS) Program Flexible Plant Operations and Generation (FPOG) Pathway is developing options to help U.S. nuclear power plants (NPPs) better integrate with intermittent wind and solar capacity and the recent surge of natural gas power generation. Research is focusing on improving NPP flexibility through hybrid production of electricity and other products, such as hydrogen (H 2 ) and energy storage for the purpose of shifting power production to a later time. In the case of H 2 production, the clean electrical and thermal power from an NPP can be used to split water using electrolysis. This report outlines the opportunity for NPPs to participate in a first-of-akind (FOAK) commercial nuclear H 2 project intended to bring industry partners together to create regional clean H 2 hubs. The Bipartisan Infrastructure Law (BIL) will fund at least one hub up to $1.25 billion as federal cost share totally no less than 50% to execute a nuclear H 2 project. The report discusses the set of activities that are now underway or that are planned for completion by the FPOG Pathway to reduce the economic, technical, regulatory, and safety risks of these projects. DOE cross-program activities are being coordinated to ensure success in the timeframe allowed by the BIL. Figure ES-1 shows the approximate schedule of coordinated research and development (R&D) and pilot demonstration projects leading up to the first commercial nuclear H 2 production project. Execution of this plan requires DOE and industry collaboration. DOE research accomplishments are being provided to the electric utilities or industries looking to participate in the H 2 hub proposal and project execution process.

08 HYDROGEN↗

NASA NTRS1999

Design of a Novel Gaseous Hydrogen-Oxygen Rocket Injector Element

NASA and Aerojet are developing a Rocket-Based Combined Cycle (RBCC) engine under the Advanced Reusable Technology program. The rocket application requires that the combustion process be stable, complete, and take place in as short a distance as possible without compromising the structural integrity of the injector itself. A novel gaseous hydrogen-oxygen rocket injector element design was arrived at through an iterative design process making extensive use of CFD simulations, which resulted in a design that is meeting design goals. Sub-scale versions of the injector have been built and tested in a unique test-rig and in a sub-scale RBCC engine. The Aerojet RBCC concept integrates small rocket thrusters into the rearfacing base area of struts placed in the flowpath of a scramjet (Supersonic Combusting Ramjet) engine. In one mode of operation, at vehicle takeoff, the rockets provide the primary thrust with additional thrust coming from an ejector effect as air is drawn into the engine inlet, entrained, and accelerated by the rocket exhaust.

Glenn, Dennis E.↗

NASA NTRS2011

High Power Flex-Propellant Arcjet Performance

A MW-class electrothermal arcjet based on a water-cooled, wall-stabilized, constricted arc discharge configuration was subjected to extensive performance testing using hydrogen and simulated ammonia propellants with the deliberate aim of advancing technology readiness level for potential space propulsion applications. The breadboard design incorporates alternating conductor/insulator wafers to form a discharge barrel enclosure with a 2.5-cm internal bore diameter and an overall length of approximately 1 meter. Swirling propellant flow is introduced into the barrel, and a DC arc discharge mode is established between a backplate tungsten cathode button and a downstream ringanode/ spin-coil assembly. The arc-heated propellant then enters a short mixing plenum and is accelerated through a converging-diverging graphite nozzle. This innovative design configuration differs substantially from conventional arcjet thrusters, in which the throat functions as constrictor and the expansion nozzle serves as the anode, and permits the attainment of an equilibrium sonic throat (EST) condition. During the test program, applied electrical input power was varied between 0.5-1 MW with hydrogen and simulated ammonia flow rates in the range of 4-12 g/s and 15-35 g/s, respectively. The ranges of investigated specific input energy therefore fell between 50-250 MJ/kg for hydrogen and 10-60 MJ/kg for ammonia. In both cases, observed arc efficiencies were between 40-60 percent as determined via a simple heat balance method based on electrical input power and coolant water calorimeter measurements. These experimental results were found to be in excellent agreement with theoretical chemical equilibrium predictions, thereby validating the EST assumption and enabling the utilization of standard TDK nozzle expansion analyses to reliably infer baseline thruster performance characteristics. Inferred specific impulse performance accounting for recombination kinetics during the expansion process implied nearly frozen flow in the nozzle and yielded performance ranges of 800-1100 sec for hydrogen and 400-600 sec for ammonia. Inferred thrust-to-power ratios were in the range of 30-10 lbf/MWe for hydrogen and 60-20 lbf/MWe for ammonia. Successful completion of this test series represents a fundamental milestone in the progression of high power arcjet technology, and it is hoped that the results may serve as a reliable touchstone for the future development of MW-class regeneratively-cooled flex-propellant plasma rockets.

Litchford, Ron J.↗

NASA NTRS1972

Development of advanced material composites for use as internal insulation for LH2 tanks (gas layer concept)

A program is described that was conducted to develop an internal insulation system for potential application to the liquid hydrogen tanks of a reusable booster, where the tanks would be subjected to repeated high temperatures. The design of the internal insulation is based on a unique gas layer concept, in which capillary or surface tension effects are used to maintain a stable gas layer, within a cellular core structure, between the tank wall and the contained liquid hydrogen. Specific objectives were to select materials for insulation systems that would be compatible with wall temperatures of 350 F and 650 F during reentry into the earth's atmosphere, and to fabricate and test insulation systems under conditions simulating the operating environment. A materials test program was conducted to evaluate the properties of candidate materials at elevated temperatures and at the temperature of liquid hydrogen, and to determine the compatibility of the materials with a hydrogen atmosphere at the appropriate elevated temperature. The materials that were finally selected included Kapton polyimide films, silicone adhesives, fiber glass batting, and in the case of the 350 F system, Teflon film.

Gille, J. P.↗

DOE OSTI2018

Diversity of Adsorbed Hydrogen on the TiC(001) Surface at High Coverages

The catalyzed dissociation of molecular hydrogen on the surfaces of diverse materials is currently widely studied due to its importance in a broad range of hydrogenation reactions that convert noxious exhaust products and/or greenhouse gases into added-value greener products, such as methanol. In the search for viable replacements for expensive late-transition-metal catalysts, TiC has been increasingly investigated as a potential catalyst for H 2 dissociation. Here, we report on a combination of experiments and density functional theory calculations on the well-defined TiC(001) surface, revealing that multiple H and H 2 species are available on this substrate, with different binding configurations and adsorption energies. Here, our calculations predict an initial occupancy of H atoms on the surface C atom sites, which then enables the subsequent stabilization of H atoms on top of the surface Ti atoms. Further H 2 can be also molecularly adsorbed over Ti sites. These theoretical predictions are in full accordance with information extracted from X-ray photoemission spectroscopy and temperature-programmed desorption experiments. The experimental results show that at high coverages of hydrogen, there is a reconstruction of the TiC(001) surface, which facilitates the binding of hydrogen.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

NASA NTRS1990

Design and analysis of composite primary structures for advanced launch vehicles

The current status of the Lightweight Composite Intertank Structures (LCIS) study, a program aimed at developing technologies required to apply advanced composite materials to launch vehicle primary structures, is reviewed. The launch system concept used for establishing design requirements consisted of a fully reusable winged booster and a partially reusable core vehicle. The component selected from this system for design and manufacturing studies was the core vehicle intertank adapter, a component consisting of approximately 26-ft diameter by 25 ft long stiffened cylindrical structure that separates the liquid hydrogen and liquid oxygen tanks on the core vehicle. The discussion covers the program approach, design requirements, material properties, structural analysis, and the test program.

Rix, C.↗

DOE OSTI2015

Irradiation Programs and Test Plans to Assess High-Fluence Irradiation Assisted Stress Corrosion Cracking Susceptibility.

. Irradiation assisted stress corrosion cracking (IASCC) is a known issue in current reactors. In a 60 year lifetime, reactor core internals may experience fluence levels up to 15 dpa for boiling water reactors (BWR) and 100+ dpa for pressurized water reactors (PWR). To support a safe operation of our fleet of reactors and maintain their economic viability it is important to be able to predict any evolution of material behaviors as reactors age and therefore fluence accumulated by reactor core component increases. For PWR reactors, the difficulty to predict high fluence behavior comes from the fact that there is not a consensus of the mechanism of IASCC and that little data is available. It is however possible to use the current state of knowledge on the evolution of irradiated microstructure and on the processes that influences IASCC to emit hypotheses. This report identifies several potential changes in microstructure and proposes to identify their potential impact of IASCC. The susceptibility of a component to high fluence IASCC is considered to not only depends on the intrinsic IASCC susceptibility of the component due to radiation effects on the material but to also be related to the evolution of the loading history of the material and interaction with the environment as total fluence increases. Single variation type experiments are proposed to be performed with materials that are representative of PWR condition and with materials irradiated in other conditions. To address the lack of IASCC propagation and initiation data generated with material irradiated in PWR condition, it is proposed to investigate the effect of spectrum and flux rate on the evolution of microstructure. A long term irradiation, aimed to generate a well-controlled irradiation history on a set on selected materials is also proposed for consideration. For BWR, the study of available data permitted to identify an area of concern for long term performance of component. The efficiency of hydrogen water chemistry mitigation technology may decrease as fluence increases for high-stress intensity factors. This report describes a program plan to determine the efficiency of hydrogen water chemistry as a function of the stress intensity factor applied and fluence. The use of existing, available, materials and the generation of additional materials via irradiation in a research reactor are considered.

36 MATERIALS SCIENCE↗

NASA NTRS1992

Design of a nickel-hydrogen battery simulator for the NASA EOS testbed

The hardware and software design of a nickel-hydrogen (Ni-H2) battery simulator (BS) with application to the NASA Earth Observation System (EOS) satellite is presented. The battery simulator is developed as a part of a complete testbed for the EOS satellite power system. The battery simulator involves both hardware and software components. The hardware component includes the capability of sourcing and sinking current at a constant programmable voltage. The software component includes the capability of monitoring the battery's ampere-hours (Ah) and programming the battery voltage according to an empirical model of the nickel-hydrogen battery stored in a computer.

Gur, Zvi↗

DOE OSTI2017

Dissociative Chemisorption and Oxidation of H 2 on the Stoichiometric IrO 2 (110) Surface

In this work, we investigated the dissociative chemisorption and oxidation of H 2 and D 2 on the stoichiometric IrO 2 (110) surface (“s-IrO 2 (110)”) using temperature programmed reaction spectroscopy (TPRS) and density functional theory (DFT) calculations. We find that the dissociative chemisorption of hydrogen occurs efficiently on s-IrO 2 (110) during adsorption at 90 K, with ~90% of the dissociated H 2 oxidizing to H 2 O during TPRS and evolving in a broad feature between 400 and 800 K. We also observe small quantities of H 2 desorbing in TPRS peaks at 200 K and 530 K, and show that these peaks arise from the desorption of molecularly-adsorbed H 2 and the recombination of atomic hydrogen, respectively. Our results demonstrate that H 2 dissociation on s-IrO 2 (110) occurs by a precursor-mediated mechanism wherein H 2 molecules adsorb strongly on coordinatively-unsaturated Ir atoms (Ircus) and the resulting σ-complexes then serve as precursors for H 2 bond cleavage. Our DFT calculations predict that H 2 adsorbs strongly on an atop-Ircus site, and that the H 2 complex can dissociate by a facile pathway involving H-transfer to a neighboring bridging O atom (Obr) to produce an H-Ircus/HObr pair. For this pathway, we predict that the energy barrier for dissociation is ~65 kJ/mol lower than the binding energy of the adsorbed H 2 complex. We also find that the total hydrogen uptake on s-IrO 2 (110) saturates at an H 2 coverage of ~0.65 ML during adsorption at 90 K, and present evidence that this limited uptake results from a strong influence of HObr groups on H 2 sigma-complex formation. Finally, we used DFT to examine pathways for H 2 O formation on s-IrO 2 (110) and find that steps leading directly to H 2 O formation are energetically demanding and likely determine the overall rate of H 2 oxidation on s-IrO 2 (110).

Dissociative Chemisorption↗

DOE OSTI2016

Progress Update on the Waste Treatment and Immobilization Plant Pulse- Jet Mixed Vessel Testing Program - 16286

The Waste Treatment and Immobilization Plant (WTP) is designed to use cylindrical-shaped pulse-jet mixers in the black cell vessels to mix the radioactive waste during process operations. Pulse-jet mixers operate like large turkey basters, using air pressure to suck radioactive waste up into the mixer and eject it back into the vessel at high velocity. Using pulse-jet mixers for keeping waste in process vessels adequately mixed is one of the design features that ensures that there are no mechanical parts inside the black cells that would require maintenance. The WTP Project is conducting a testing program to ensure the pulse-jet mixed vessels can address three design and nuclear safety concerns: 1) pulse jet mixer controls, 2) hydrogen gas generation, and 3) the potential for inadvertent criticality in the vessels. The currently planned pulse-jet mixed vessel testing program is divided into three major test campaigns. The first campaign consists of testing to demonstrate pulse-jet mixed vessel control system design and operating concepts. The second test campaign consisted of informational testing of select prototypic PJM vessel features in a reduced scale facility. This testing informed decision making on selection of different mixing system configurations. This test campaign was completed in March 2015. The third test campaign is planned to test the complete functionality of a pulse-jet mixed vessel at full-scale using a prototype standardized high-solids vessel design. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗