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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 163 records · Page 9
All sourcesNASA NTRSDOE OSTI
NASA NTRS2014

CO Self-Shielding as a Mechanism to Make O-16 Enriched Solids in the Solar Nebula

Photochemical self-shielding of CO has been proposed as a mechanism to produce solids observed in the modern, O-16 depleted solar system. This is distinct from the relatively O-16 enriched composition of the solar nebula, as demonstrated by the oxygen isotopic composition of the contemporary sun. While supporting the idea that self-shielding can produce local enhancements in O-16 depleted solids, we argue that complementary enhancements of O-16 enriched solids can also be produced via CO-16 based, Fischer-Tropsch type (FTT) catalytic processes that could produce much of the carbonaceous feedstock incorporated into accreting planetesimals. Local enhancements could explain observed O-16 enrichment in calcium-aluminum-rich inclusions (CAIs), such as those from the meteorite, Isheyevo (CH/CHb), as well as in chondrules from the meteorite, Acfer 214 (CH3). CO selfshielding results in an overall increase in the O-17 and O-18 content of nebular solids only to the extent that there is a net loss of CO-16 from the solar nebula. In contrast, if CO-16 reacts in the nebula to produce organics and water then the net effect of the self-shielding process will be negligible for the average oxygen isotopic content of nebular solids and other mechanisms must be sought to produce the observed dichotomy between oxygen in the Sun and that in meteorites and the terrestrial planets. This illustrates that the formation and metamorphism of rocks and organics need to be considered in tandem rather than as isolated reaction networks.

Solar Nebula↗
NASA NTRS2015

Solid-State Cloud Radar System (CRS) Upgrade and Deployment

The recent decade has brought rapid development in solid-state power amplifier (SSPA) technology. This has enabled the use of solid-state precipitation radar in place of high-power and high-voltage systems such as those that use Klystron or Magnetron transmitters. The NASA Goddard Space Flight Center has recently completed a comprehensive redesign of the 94 gigahertz Cloud Radar System (CRS) to incorporate a solid-state transmitter. It is the first cloud radar to achieve sensitivity comparable to that of a high-voltage transmitter using solid-state. The NASA Goddard Space Flight Center's Cloud Radar System (CRS) is a 94 gigahertz Doppler radar that flies on the NASA ER-2 high-altitude aircraft. The upgraded CRS system utilizes a state-of-the-art solid-state 94 gigahertz power amplifier with a peak transmit power of 30 watts. The modernized CRS system is detailed here with data results from its deployment during the 2014 Integrated Precipitation and Hydrology Experiment (IPHEX).

Radar Radiometer Sampling↗
NASA NTRS2016

Development Status for a Combined Solid Oxide Co-Electrolyzer and Carbon Formation Reactor System for Oxygen Regeneration

A critical component in spacecraft life support loop closure is the removal of carbon dioxide (CO2, produced by the crew) from the cabin atmosphere and chemical reduction of this CO2 to recover the oxygen. In 2015, we initiated development of an oxygen recovery system for life support applications consisting of a solid oxide co-electrolyzer (SOCE) and a carbon formation reactor (CFR). The SOCE electrolyzes a combined stream of carbon dioxide (CO2) and water (H2O) gas mixtures to produce synthesis gas (e.g., CO and H2 gas) and pure dry oxygen as separate products. This SOCE is being developed from a NASA GRC solid oxide fuel cell and stack design originally developed for aeronautics long-duration power applications. The CFR, being developed by pHMatter LLC, takes the CO and H2 output from the SOCE, and converts it primarily to solid carbon (C(s)) and H2O and CO2. Although the solid carbon accumulates in the CFR, the innovative design allows easy removal of the carbon product, requiring minimal crew member (CM) time and low resupply mass (1.0 kg/year/CM) for replacement of the solid carbon catalyst, a significant improvement over previous Bosch reactor approaches. In this work, we will provide a status of our Phase I efforts in the development and testing of both the SOCE and CFR prototype units, along with an initial assessment of the combined SOCE-CFR system, including a mass and power projections, along with an estimate of the oxygen recovery rate.

air revitalization↗
NASA NTRS2019

Specific Impulse of Electric Solid Propellant in an Electrothermal Ablation-Fed Pulsed Plasma Thruster

Electric solid propellants are advanced solid chemical rocket propellants that can be controlled (ignited, throttled, and extinguished) through the application and removal of an electric current. Recent work has focused on application of this propellant in an electrothermal ablation-fed pulsed plasma thruster. In this paper, impulse bit measurements in such devices fed by either the electric solid propellant or a traditional state-of-the-art propellant, polytetrafluoroethylene, are expanded upon. It is demonstrated that a surface layer in the hygroscopic electric solid propellant is rapidly ablated over the first few discharges of the device, which correspondingly decreases specific impulse relative to the traditional polytetrafluoroethylene propellant. Correcting these data by subtracting the early discharge ablation mass loss measurements yields a corrected electric solid propellant specific impulse of approximately 300 s. As the test duration increases to a large number of discharges, and the initial mass loss is a reduced fraction of the total, the effect of absorbed water in the propellant is decreased and the specific impulse without any corrections approaches the corrected 300 s value.

Glascock, Matthew S.↗
NASA NTRSDate not supplied

Extinction of the Stagnation Point Diffusion Flame: Effect of Conductive Heat Loss into Solid Interior

The planned microgravity experiment Growth and Extinction Limit (GEL) is designed to study the material flammability and extinction of thermally thick solid with an emphasis to quantify the effect of conductive heat loss into the solid interior by measuring the in-depth temperature profile. To obtain a more detailed understanding of the extinction phenomena, a previously developed one-dimensional axisymmetric stagnation-point diffusion flame model is expanded to account for the excessive heat loss into the solid beyond the steady burning state. This is important because for thick solids, this is important because the burning period can have a long and slow solid transient with a quasi-steady gas -phase. A non-dimensional excessive conductive heat loss parameter Ψ is defined in the paper and extensive numerical computations have been performed to determine the extinction boundary and the characteristics of near-limit flames. The classical U-shaped flammability boundary in the oxygen vs. stretch rate plot now becomes a series of U-shaped boundaries as a function of Ψ. For a given oxygen ambient, extinction boundary is a function of Ψ. The boundary consists of a blowoff branch and a radiative quenching branch. This is similar to the steady burning flammability boundary (Ψ =0) in the oxygen vs stretch rate plot. Extensive computed data including flame and pyrolysis temperatures, burning rate, flame standoff distance, and reaction rate are presented along the extinction boundaries. In particular, we note that the non-dimensional gas reaction rate is the ratio of diffusion reaction time to the reaction diffusion time, so it has the classical Damhkoler number character. By examining the maximum non-dimensional reaction rates, we observe that along the extinction boundaries, they are approximate constant across the entire range of stretch rates (from quenching to blow-off). These critical values are of the order unity but may vary in different oxygen ambient. The implication will be discussed in the presentation together with the near-limit flame structures.

Chengyao Li↗
NASA NTRSDate not supplied

Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) Beyond Li-Ion: Technology to Enable Sustainable Electric Aviation

All-electric and hybrid electric aerovehicle concepts face numerous technical barriers prior to their introduction into the consumer marketplace in order to meet sustainable aviation goals. One of the primary barriers to overcome is developing an energy dense storage system capable of meeting the rigorous aerospace safety and performance criteria. Additionally, the electric aviation market requires that the batteries be fabricated in a sustainable manner with materials that are readily available and abundant within the U.S. to ensure there are no supply chain issues during manufacturing. The performance metrics to enable electric aviation are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. The hybrid cathode has been developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte has been used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This poster summarizes recent results from battery component optimization to scale-up production of full SABERS pouch cells.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRS2004

QuakeSim and the Solid Earth Research Virtual Observatory

We are developing simulation and analysis tools in order to develop a solid Earth science framework for understanding and studying active tectonic and earthquake processes. The goal of QuakeSim and its extension, the Solid Earth Research Virtual Observatory (SERVO), is to study the physics of earthquakes using state-of-the-art modeling, data manipulation, and pattern recognition technologies. We are developing clearly defined accessible data formats and code protocols as inputs to simulations, which are adapted to high-performance computers. The solid Earth system is extremely complex and nonlinear resulting in computationally intensive problems with millions of unknowns. With these tools it will be possible to construct the more complex models and simulations necessary to develop hazard assessment systems critical for reducing future losses from major earthquakes. We are using Web (Grid) service technology to demonstrate the assimilation of multiple distributed data sources (a typical data grid problem) into a major parallel high-performance computing earthquake forecasting code. Such a linkage of Geoinformatics with Geocomplexity demonstrates the value of the Solid Earth Research Virtual Observatory (SERVO) Grid concept, and advances Grid technology by building the first real-time large-scale data assimilation grid.

virtual observatory↗
NASA NTRSDate not supplied

A materials-informatics based study of solid electrolytes and protective coatings for Li batteries

All-solid-state batteries with Li metal anode can address the safety issues surrounding traditional Li-ion batteries as well as the demand for higher energy densities. However, the development of solid electrolytes and protective coatings simultaneously possessing high ionic conductivity and wide electrochemical stability has proven to be a challenge. Here, we present a data-driven approach to explore the Li compound space for promising solid electrolytes and coatings. This is accomplished through the generation of a large database of battery-related materials properties of Li compounds by computing Li+ migration barriers using bond-valence-based pair potentials, and stability windows using density functional theory energies. Using this database, we implement machine learning models that can accurately predict migration barriers and electrochemical stability windows for any new Li compound. Through feature engineering, we ensure that our models are both accurate and interpretable. We perform feature importance analysis on our models to highlight materials properties that can be tuned for future design of coatings/electrolytes. Our database and informatics approach provide a valuable tool for the rapid discovery of new solid-state battery chemistries.

Solid state batteries↗
NASA NTRSDate not supplied

Interpretable Tree-Based and Graph Neural Network Approaches for Novel Solid State Electrolyte Design

All-solid-state batteries with Li metal anode can address the safety issues surrounding traditional Li-ion batteries as well as the demand for higher energy densities. However, the development of solid electrolytes simultaneously possessing high ionic conductivity and good chemical and electrochemical stabilities has proven to be a challenge. I will present our informatics approach to explore the Li compound space for promising solid electrolytes using high-throughput multi-property screening and interpretable machine learning. This is accomplished through the generation of a large database of battery-related materials properties of Li compounds. We use tree-based ensemble learning methods and graph neural network approaches to accurately learn relationships between crystal structures and corresponding thermodynamic and kinetic properties, with interpretability being a major focus. Our models give us the ability to enable rapid discovery and design of novel solid-state battery chemistries.

Materials discovery↗
NASA NTRS1972

Technical report analysis and design: Study of solid rocket motors for a space shuttle booster, volume 2, book 1, supplement 1

An analysis and design effort was conducted as part of the study of solid rocket motor for a space shuttle booster. The 156-inch-diameter, parallel burn solid rocket motor was selected as its baseline because it is transportable and is the most cost-effective, reliable system that has been developed and demonstrated. The basic approach was to concentrate on the selected baseline design, and to draw from the baseline sufficient data to describe the alternate approaches also studied. The following conclusions were reached with respect to technical feasibility of the use of solid rocket booster motors for the space shuttle vehicle: (1) The 156-inch, parallel-burn baseline SRM design meets NASA's study requirements while incorporating conservative safety factors. (2) The solid rocket motor booster represents a cost-effective approach. (3) Baseline costs are conservative and are based on a demonstrated design. (4) Recovery and reuse are feasible and offer substantial cost savings. (5) Abort can be accomplished successfully. (6) Ecological effects are acceptable.

Source record↗
NASA NTRS1972

Study of solid rocket motor for space shuttle booster, volume 2, book 1

The technical requirements for the solid propellant rocket engine to be used with the space shuttle orbiter are presented. The subjects discussed are: (1) propulsion system definition, (2) solid rocket engine stage design, (3) solid rocket engine stage recovery, (4) environmental effects, (5) manrating of the solid rocket engine stage, (6) system safety analysis, and (7) ground support equipment.

Source record↗
NASA NTRS1974

Comparison of experimental and predicted performance of 150-millimeter-bore solid and drilled ball bearings to 3 million DN

Seven 150-millimeter-bore ball bearings were run under 8900-newton (2000-lbf) thrust load at speeds from 6670 to 20,000 rpm (1 million to 3 million DN). Four of the bearings had conventional solid balls, and three bearings had drilled (cylindrically hollow) balls with 50-percent mass reduction. The bearings were under-race cooled and slot lubricated with a type 2 ester oil at flow rates from 4.35 x 0.001 to 5.94 x 0.001 cubic meter/min (1.15 to 1.57 gal/min). Friction torque and temperature were measured on all bearings. While there was considerable spread in the temperature data, the drilled ball bearings tended to run slightly cooler than the solid ball bearings at higher speeds. No significant difference in torque was noted, however, between the solid and drilled ball bearings. One bearing of each type was rerun at 17,800-newton (4000-lbf) thrust load. The solid ball bearings performed satisfactorily at 3 million DN. However, at about 2 million DN the drilled ball bearing experienced a broken ball, and cracks appeared in other balls as a result of flexure fatigue. Metallurgical examination of the cracked balls indicated a brittle structure in the bore of the drilled balls.

Scibbe, H. W.↗
NASA NTRS1973

Restartable solid motor stage for shuttle applications

The application of restartable solid motor stages to shuttle missions has been shown to provide a viable supplement to the shuttle program. Restartable solid motors in the 3000 pound class provide a small expendable transfer stage that reduces the demand on the shuttle for the lower energy missions. Shuttle operational requirements and preliminary performance data provided an input for defining design features required for restartable solid motor applications. These data provided a basis for a configuration definition that is compatible with shuttle operations. Mission by mission analysis showed the impact on a NASA supplied mission model. The results showed a 15% reduction in the number of shuttle flights required. In addition the amount of shuttle capability used to complete the mission objectives was significantly reduced. For example, in the 1979 missions there was a 62% reduction in shuttle capability used. The study also showed that the solid motor could provide a supplement to the TUG that would allow TUGS to be used in a recoverable rather than an expendable mode. The study shows a 71% reduction in the number of TUGs that would be expended.

Rohrbaugh, D. J.↗
NASA NTRS1974

Solubility and thermodynamic properties of oxygen in solid molybdenum

A formula is obtained for the solubility of oxygen in solid Mo, determined in the range from 1400 to 1900 C by equilibrating rods of zone-refined Mo with mixtures of Mo and MoO2 powders. Using the known value of the free energy of formation of MoO2, a formula is obtained for the chemical potential of oxygen in the dilute solid solution. The heat of solution of oxygen in solid Mo and the excess entropy for the interstitial solid solution are also determined, assuming that the oxygen atoms reside in the octahedral interstices of bcc Mo.

Srivastava, S. C.↗
NASA NTRS1974

Energy recovery from solid waste

A recent group study on the problem of solid waste disposal provided a decision making model for a community to use in determining the future for its solid waste. The model is a combination of the following factors: technology, legal, social, political, economic and environmental. An assessment of local or community needs determines what form of energy recovery is desirable. A market for low pressure steam or hot water would direct a community to recover energy from solid waste by incineration to generate steam. A fuel gas could be produced by a process known as pyrolysis if there is a local market for a low heating value gaseous fuel. Solid waste can also be used directly as a fuel supplemental to coal in a steam generator. An evaluation of these various processes is made.

Dalton, C.↗
NASA NTRS1976

Dynamics of solid lubrication as observed by optical microscopy

A bench metallograph was converted into a micro contact imager by the addition of a tribometer employing a steel ball in sliding contact with a glass disk. The sliding contact was viewed in real time by means of projection microscope optics. The dynamics of abrasive particles and of solid lubricant particles within the contact were observed in detail. The contact was characterized by a constantly changing pattern of elastic strain with the passage of surface discontinuities and solid particles. Abrasive particles fragmented upon entering the contact, embedded in one surface and scratched the other; in contrast, the solid lubricant particles flowed plastically into thin films. The rheological behavior of the lubricating solids gave every appearance of a paste-like consistency within the Hertzian contact.

Sliney, H. E.↗
NASA NTRS1976

Analytical comparison of effects of solid-friction and viscous structural damping on panel flutter

A Galerkin modal analysis is presented that accounts for the effects of both solid friction and viscous structural damping on panel flutter, based on unsteady aerodynamic forces from supersonic potential flow. The eigensolutions are made by complex eigenvalue computer routines. Markedly different effects on the flutter boundary of the two types of structural damping are obtained. This result establishes that there is not, in general, an "equivalent viscous" damping for solid-friction damping. For the limiting case of the static-aerodynamic approximation, a substantially different flutter dynamic pressure is obtained for solid friction identically zero compared with solid friction approaching zero as a limit. Use of the quasi-static aerodynamic approximation eliminates that difference.

Cunningham, H. J.↗
NASA NTRS1976

Dynamics of solid lubrication as observed by optical microscopy

A bench metallograph was converted into a 'micro contact imager' by the addition of a tribometer employing a steel ball in sliding contact with a glass disk. The sliding contact was viewed in real time by means of projection microscope optics. The dynamics of abrasive particles and of solid lubricant particles within the contact were observed in detail. The contact was characterized by a constantly changing pattern of elastic strain with the passage of surface discontinuities and solid particles. Abrasive particles fragmented upon entering the contact, embedded in one surface and scratched the other; in contrast, the solid lubricant particles flowed plastically into thin films. The rheological behavior of the lubricating solids gave every appearance of a paste-like consistency within the Hertzian contact.

Sliney, H. E.↗