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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 415 records · Page 23
All sourcesNASA NTRSDOE OSTI
NASA NTRS2012

High-Temperature Coatings Offer Energy Savings

The U.S. X-Plane Program included the first-of-its-kind research in aerodynamics and astronautics with experimental vehicles, including the first aircraft to break the sound barrier; the first aircraft to fly in excess of 100,000, then 200,000, and then 300,000 feet; and the first aircraft to fly at three, four, five, and then six times the speed of sound. During the 1990s, NASA started developing a new thermal protection material to test on the X-33 and X-34 supersonic aircraft. The X-33 was intended to demonstrate the technologies needed for a new reusable launch vehicle and was projected to reach an altitude of approximately 50 miles and speeds of more than Mach 11. The X-34, a small, reusable technology demonstrator for a launch vehicle, was intended to reach an altitude of 250,000 feet and fly at speeds of Mach 8. As a result of its research and development efforts, NASA s Ames Research Center invented the Protective Ceramic Coating Material (PCCM). Applied to a surface, the thin, lightweight coating could protect the material underneath from extreme temperatures. The capability of the technology came from its emissivity, which radiated heat away from the surface it covered, thereby decreasing the amount of heat transferred to the underlying material. PCCM not only increased the capability of materials to withstand higher temperatures, it also exhibited impressive thermal shock, vibration, and acoustic performance. In addition, it proved to be resistant to abrasion and mechanical damage and was also environmentally safe, due to it being water-based and containing no solvents. Even though funding for the X-33 and X-34 ended in 2001, PCCM continued on a path of innovation.

Source record↗
NASA NTRS2024

The Roman Space Telescope Observatory Build, Test and Verification Status

The Nancy Grace Roman Space Telescope (“Roman”) was prioritized by the 2010 Decadal Survey in Astronomy and Astrophysics and is NASA’s next astrophysics flagship observatory. Launching no earlier than 2026, it will conduct several wide field and time domain surveys, as well as conduct an exoplanet census. Roman’s large field of view, agile survey capabilities, and excellent stability enable these objectives, yet present unique engineering and test challenges. The Roman Observatory comprises a Spacecraft and the Integrated Payload Assembly (IPA), the latter of which includes the Optical Telescope Assembly (OTA), the primary science Wide Field Instrument, a technology demonstration Coronagraph Instrument, and the Instrument Carrier, which meters the OTA to each instrument. The Spacecraft supports the IPA and includes the Bus, Solar Array Sun Shield, Outer Barrel Assembly, and Deployable Aperture Cover. It provides all required power, command handling, attitude control, communications, data storage, and stable thermal control functions as well as shading and straylight protection across the entire field of regard. This paper presents the Observatory as it begins integration and test, as well as describes key test and verification activities.

Infrared Missions↗
NASA NTRS2013

Hydrogen-Enhanced Lunar Oxygen Extraction and Storage Using Only Solar Power

The innovation consists of a thermodynamic system for extracting in situ oxygen vapor from lunar regolith using a solar photovoltaic power source in a reactor, a method for thermally insulating the reactor, a method for protecting the reactor internal components from oxidation by the extracted oxygen, a method for removing unwanted chemical species produced in the reactor from the oxygen vapor, a method for passively storing the oxygen, and a method for releasing high-purity oxygen from storage for lunar use. Lunar oxygen exists in various types of minerals, mostly silicates. The energy required to extract the oxygen from the minerals is 30 to 60 MJ/kg O. Using simple heating, the extraction rate depends on temperature. The minimum temperature is approximately 2,500 K, which is at the upper end of available oven temperatures. The oxygen is released from storage in a purified state, as needed, especially if for human consumption. This method extracts oxygen from regolith by treating the problem as a closed batch cycle system. The innovation works equally well in Earth or Lunar gravity fields, at low partial pressure of oxygen, and makes use of in situ regolith for system insulation. The innovation extracts oxygen from lunar regolith using a method similar to vacuum pyrolysis, but with hydrogen cover gas added stoichiometrically to react with the oxygen as it is produced by radiatively heating regolith to 2,500 K. The hydrogen flows over and through the heating element (HE), protecting it from released oxygen. The H2 O2 heat of reaction is regeneratively recovered to assist the heating process. Lunar regolith is loaded into a large-diameter, low-height pancake reactor powered by photovoltaic cells. The reactor lid contains a 2,500 K HE that radiates downward onto the regolith to heat it and extract oxygen, and is shielded above by a multi-layer tungsten radiation shield. Hydrogen cover gas percolates through the perforated tungsten shielding and HE, preventing oxidation of the shielding and HE, and reacting with the oxygen to form water vapor. The water vapor is filtered through solid regolith to remove unwanted extraction byproducts, and then condensed to a liquid state and stored at 300 to 325 K. Conversion to usable oxygen is achieved by pumping liquid water into a high-pressure electrolyzer, storing the gaseous oxygen at high pressure for use, and diverting the hydrogen back to the reactor or to storage. The results from this design effort show that this oxygen-generating concept can be developed in an efficient system with low specific mass. Advantages include use of regolith as an oxygen source, filter, and thermal insulator. The system can be tested in Earth gravity and can be expected to operate similarly in lunar gravity. The system is scalable, either by increasing the power level and output of a standard module, or by employing multiple modules.

Burton, rodney↗
DOE OSTI2025

In Situ MOF Pyrolysis Construction of Hierarchical Porous Co‐Nanoparticles/Carbon Cloth Composites for Enhanced Electromagnetic Wave Shielding and Absorption

The development of high-performance electromagnetic protection materials integrating broadband absorption and effective shielding capabilities is hindered by challenges in simultaneously optimizing multiple electromagnetic properties through conventional material designs. This study pioneers a hierarchical porous Co nanoparticle/carbon cloth (Co/CC) composite via controlled annealing of a Co-MOF precursor on carbon cloth. The Co-MOF served a dual role as both magnetic source and pore-forming agent, enabling in situ generation of uniformly dispersed Co nanoparticles and creation of abundant pores/interfaces on the CC fibers during pyrolysis. This unique architecture synergistically enhanced dielectric loss (via interfacial/dipolar polarization) and magnetic loss (via natural resonance, exchange interactions, and eddy currents), significantly improving impedance matching. The hierarchical pores further functioned as integrated “absorption–reflection” units for efficient electromagnetic energy attenuation. Consequently, the Co/CC composite annealed at 800°C (Co/CC-800) achieves minimum reflection loss (−40.69 dB) and 120% effective absorption bandwidth extension (6.16 GHz) as a filler, and exhibits superior electromagnetic interference shielding effectiveness (46.66 dB) as an integrated component. Significantly, Co/CC-800 demonstrated robust photothermal and electrothermal conversion capabilities, ensuring operational stability in ice-covered and humid harsh environments. This work pioneers a pore-structure-mediated strategy to harmonize dielectric–magnetic synergy, providing a new paradigm for designing advanced multifunctional electromagnetic protection materials.

dielectric‐magnetic synergy↗
NASA NTRS1965

Second Symposium on Protection Against Radiations in Space

All space vehicles will be exposed to natural charged particle radiation fields. The effects and possible problems imposed by such radiations are of great concern to those actively engaged in the exploration of space. Materials and components, which may be damaged by the radiation, frequently can be replaced by more radiation resistant items; however, replacement systems are not always possible or practical and, hence, protective measures in the form of shielding must be employed. (One of the more radiation-sensitive systems to be flown in space is man himself.) Many groups are engaged in research on the attenuation and penetration of high-energy space radiation and on the development of methods for the design of shielding which affords protection against the radiation. The purpose of the Second Symposium on Protection Against Radiations in Space, like that of the First, was to bring these groups together to exchange information and share ideas. These proceedings are the written record of the Second Symposium. Invited papers covering the space radiation environment, radiobiological effects, and radiation effects on materials and components comprised the first three sessions. By defining the radiation problems in space and providing for the proper assessment of the radiation effects and shielding requirements, these papers helped to establish the necessary background for the shielding papers which followed in the fourth session.

radiation protection↗
NASA NTRS1978

Overview of safety research

Aircraft safety is reviewed by first establishing a perspective of air transportation accidents as a function of calendar year, geographic area, and phase of flight, and then by describing the threats to safety and NASA research underway in the three representative areas of engine operational problems, meteorological phenomena, and fire. Engine rotor burst protection, aircraft nacelle fire extinguishment, the aircraft-weather interface, severe weather wind shears and turbulence, clear air turbulence, and lightning are among the topics covered. Fire impact management through fire resistant materials technology development is emphasized.

Enders, J. H.↗
NASA NTRS1998

Fabrication and Resistivity of IBr Intercalated Vapor-Grown Carbon Fiber Composites

Composites using vapor-crown carbon fibers (VGCF), the most conductive of the carbon fiber types, are attractive for applications where low density, high strength, and at least moderate conductivity are required, such as electromagnetic interference shielding covers for spacecraft. The conductivity can be enhanced another order of magnitude by intercalation of the VGCF. If a high Z intercalate is used, the protection of components from ionizing radiation can be enhanced also. Thus, the intercalation of VGCF with IBr is reported. Since composite testing is required to verify properties, the intercalation reaction optimization, stability of the intercalation compound, scale-up of the intercalation reaction, composite fabrication, and resistivity of the resulting composites is also reported. The optimum conditions for low resistivity and uniformity for the scaled up reaction (20-30 g of product) were 114 C for at least 72 hr, yielding a fiber with a resistivity of 8.7+/-2 micro-Omega-cm. The thermal stability of these fibers was poor, with degradation occurring at temperatures as low as 40 C in air, though they were insensitive to water vapor. Composite resistivity was 20-30 micro-Omega-cm, as measured by contactless conductivity measurements, about a factor of five higher than would be expected from a simple rule of mixtures. The addition of 1.0 percent Br2, intercalated microfibers increased the resistivity of the composites by more than 20 percent.

Gaier, James R.↗
NASA NTRS2016

Satellite Communications for Unmanned Aircraft C2 Links: C-Band, Ku-Band and Ka-Band

Unmanned aircraft (UA) that require access to controlled (or non-segregated) airspace require a highly reliable and robust command and control (C2) link, operating over protected aviation spectrum. While operating within radio line-of-sight (LOS) UA can make use of air-to-ground C2 links to terrestrial stations. When operating beyond LOS (BLOS) where a group of networked terrestrial stations does not exist to provide effective BLOS coverage, a satellite communications link is required. Protected aviation spectrum for satellite C2 links has only recently been allocated in bands where operational satellites exist. A previously existing C-Band allocation covers a bands where there are currently no operational satellites. The new allocations, within the Fixed Satellite Service bands at Ku and Ka-Bands will not be finalized until 2023 due to the need for the development of standards and technical decisions on the operation of UA satellite C2 links within these bands. This paper provides an overview of BLOS satellite C2 links, some of the conditions which will need to be met for the operation of such links, and a look at some aspects of spectrum sharing which may constrain these operations.

radiofrequency spectrum↗
NASA NTRSDate not supplied

Inverse Estimation of Mars 2020 Entry Aeroheating Environments Using MEDLI2 Flight Data

The Mars Entry, Descent, and Landing Instrumentation 2 (MEDLI2) sensor suite collected heating and pressure data during entry into Mars' atmosphere of the Mars 2020 Perseverance rover. MEDLI2 included thermocouples, heat flux sensors, and pressure transducers on both the heatshield and the backshell. This paper covers the inverse estimation of heatshield and backshell surface heating based on the MEDLI2 Instrumented Sensor Plugs (MISPs), a network of thermocouples embedded in thermal protection system plugs across the aeroshell. Monte Carlo analysis was conducted to assess the sensitivity of the surface heat rate and temperature to uncertainties in thermocouple depth and material properties such as density, specific heat capacity, and thermal conductivity. Data from each MISP was also used to estimate the local time of transition from laminar to turbulent flow at each plug location.

Hannah S Alpert↗
DOE OSTI2025

Bismuthene Under Cover: Graphene Intercalation of a Large Gap Quantum Spin Hall Insulator

Abstract The quantum spin Hall insulator bismuthene, a two‐third monolayer of bismuth on SiC(0001), is distinguished by helical metallic edge states that are protected by a groundbreaking 800 meV topological gap, making it ideal for room temperature applications. This massive gap inversion arises from a unique synergy between flat honeycomb structure, strong spin orbit coupling, and an orbital filtering effect that is mediated by the substrate. However, the rapid oxidation of bismuthene in air has severely hindered the development of applications, so far confining experiments to ultra‐high vacuum conditions. Intercalating bismuthene between SiC and a protective sheet of graphene, this barrier is successfully overcome. As demonstrated by scanning tunneling microscopy and photoemission spectroscopy, graphene intercalation preserves the structural and topological integrity of bismuthene, while effectively shielding it from oxidation in air. Hereby, hydrogen is identified as the critical process gas that was missing in previous bismuth intercalation attempts. These findings facilitate ex‐situ experiments and pave the way for the development of bismuthene based devices, signaling a significant step forward in the development of next‐generation technologies.

Chemistry↗
DOE OSTI2022

Systems and Implementation: Integrating Unmanned Aircraft Systems into Physical Protection Systems at Fixed Sites and During Transportation

Physical protection systems, and response forces in particular, are designed to prevent an adversary from successfully completing a malevolent act against a facility or transport operations. Timely detection and assessment of any potential adversary action against a target is an essential element of materials security. The timely detection and assessment must then be followed-up by a capable and timely response that might be enhanced with the additional situational awareness provided by unmanned aircraft systems (UAS). The United States Department of Energy’s National Nuclear Security Administration Office of International Nuclear Security has been exploring capabilities provided by UAS to support response force operations within the physical protection system. UAS have the potential to provide response force commanders and operators with situational awareness in assessing adversary locations and actions as well as the locations of responders. UAS may be utilized for area searches ahead of responder pathways to identify potential threats and to provide situational awareness of areas not normally covered by cameras (such as areas outside the fence line outside at fixed facilities). In addition, UAS can provide real-time information to transportation convoy teams that pass through constantly changing public access environments. This paper will provide operational recommendations to be addressed when integrating UAS into existing physical protection systems at fixed sites and during transport. Recommendations will include aspects of the following: needs analysis; tactics and techniques to support detection and assessment as well as response force deployment; remote pilot selection, qualifications, training, and currency; UAS selection criteria; UAS laws and regulations; possible cost sharing with other facility operations; and on-scene emergency management.

Stockwell, Brandon↗
NASA NTRS1990

Space-Spurred Metallized Materials

Spurred R&D toward improved vacuum metallizing techniques led to an extensive line of commercial products, from insulated outdoor garments to packaging for foods, from wall coverings to window shades, from life rafts to candy wrappings, reflective blankets to photographic reflectors. Metallized Products, Inc. (MPI) was one of the companies that worked with NASA in development of the original space materials. MPI markets its own metallized products and supplies materials to other manufacturers. One of the most widely used MPI products is TXG laminate. An example is a reflective kite, the S.O.S. Signal Kite that can be flown as high as 200 feet to enhance radar and visual detectability. It offers a boon to campers, hikers, mountain climbers and boaters. It is produced by Solar Reflections, Inc. The company also markets a solar reflective hat. Another example is by Pro-Tektion, Inc. to provide protection for expensive musical equipment that have sensitive electronic components subject to damage from the heat of stage lights, dust, or rain at outdoor concerts. MP supplied the material and acceptance of the covers by the sound industry has been excellent.

Source record↗
NASA NTRS2009

NASA Biological Specimen Repository

The NASA Biological Specimen Repository (NBSR) has been established to collect, process, annotate, store, and distribute specimens under the authority of the NASA/JSC Committee for the Protection of Human Subjects. The International Space Station (ISS) provides a platform to investigate the effects of microgravity on human physiology prior to lunar and exploration class missions. The NBSR is a secure controlled storage facility that is used to maintain biological specimens over extended periods of time, under well-controlled conditions, for future use in approved human spaceflight-related research protocols. The repository supports the Human Research Program, which is charged with identifying and investigating physiological changes that occur during human spaceflight, and developing and implementing effective countermeasures when necessary. The storage of crewmember samples from many different ISS flights in a single repository will be a valuable resource with which researchers can validate clinical hypotheses, study space-flight related changes, and investigate physiological markers All samples collected require written informed consent from each long duration crewmember. The NBSR collects blood and urine samples from all participating long duration ISS crewmembers. These biological samples are collected pre-flight at approximately 45 days prior to launch, during flight on flight days 15, 30, 60 120 and within 2 weeks of landing. Postflight sessions are conducted 3 and 30 days following landing. The number of inflight sessions is dependent on the duration of the mission. Operations began in 2007 and as of October 2009, 23 USOS crewmembers have completed or agreed to participate in this project. As currently planned, these human biological samples will be collected from crewmembers covering multiple ISS missions until the end of U.S. presence on the ISS or 2017. The NBSR will establish guidelines for sample distribution that are consistent with ethical principles, protection of crewmember confidentiality, prevailing laws and regulations, intellectual property policies, and consent form language. A NBSR Advisory Board composed of representatives of all participating agencies will be established to evaluate each request by an investigator for use of the samples to ensure the request reflects the mission of the NBSR.

Pietrzyk, Robert↗
DOE OSTI2020

Ready for Renewables: Grid Planning and Competitive Renewable Energy Zones (CREZ) in the Philippines

The Department of Energy of the Philippines launched the competitive renewable energy zones (CREZ) process to help achieve the country's goals of scaling up renewable energy generation on the power system and to ensure sustainable, secure, reliable, accessible, and affordable energy. The CREZ process identifies the most economic renewable energy resource areas so transmission planning and expansion can accelerate their development. By proactively focusing transmission expansion to these resource areas, renewable energy generation development obstacles such as transmission access, energy curtailment, land permitting (such as protected or high-slope areas), and regulatory barriers are easier to overcome thus, reducing risk for private sector renewable energy investment. This report is will cover the outputs of the CREZ process, the development of the outputs through stakeholder-driven coordination, and how this process will help the Philippines achieve their renewable energy goals.

24 POWER TRANSMISSION AND DISTRIBUTION↗
NASA NTRS1976

Water hyacinths for upgrading sewage lagoons to meet advanced wastewater treatment standards, part 2

Field tests using water hyacinths as biological filtration agents were conducted in the Mississippi gulf coast region. The plants were installed in one single cell and one multiple cell sewage lagoon systems. Water hyacinths demonstrated the ability to maintain BOD5 and total suspended solid (TSS) levels within the Environmental Protection Agency's prescribed limits of 30 mg/lBOD5 and 30 mg/l TSS. A multiple cell sewage lagoon system consisting of two aerated and one water hyacinth covered cell connected in series demonstrated the ability to maintain BOD5 and TSS levels below 30 mg/l year-round. A water hyacinth covered lagoon with a surface area of 0.28 hectare containing a total volume of 6.8 million liters demonstrated the capacity to treat 437,000 to 1,893,000 liters of sewage influent from 2.65 hectares of aerated lagoons daily and produce an effluent that met or exceeded standards year-round.

Wolverton, B. C.↗
NASA NTRS1991

Controlling hazardous energy sources (lockout/tagout)

The minimum requirements as established by the Occupational Safety and Health Administration (OSHA) standard 29 CFR 1910.147 are discussed for preventing the unexpected operation of equipment or release of energy which could cause injury to personnel, damage to equipment, harm to the environment, or loss or compromise of test data. Safety requirements both for government and contractor personnel are explained for potentially hazardous energy sources during work operations at LeRC (Cleveland and Plum Brook Stations). Basic rules are presented to ensure protection against harmful exposures, and baseline implementation requirements are discussed from which detailed lockout/tagout procedures can be developed for individual equipment items. Examples of energy sources covered by this document include electrical, pneumatic, mechanical, chemical, cryogenic, thermal, spring tension/compression suspended or moving loads, and other potentially hazardous sources. Activities covered by this standard include, but are not limited to, construction, maintenance, installation, calibration, inspection, cleaning, or repair.

Dominguez, Manuel B.↗
NASA NTRS2012

Structures and Mechanisms Design Concepts for Adaptive Deployable Entry Placement Technology

System studies have shown that large deployable aerodynamic decelerators such as the Adaptive Deployable Entry and Placement Technology (ADEPT) concept can revolutionize future robotic and human exploration missions involving atmospheric entry, descent and landing by significantly reducing the maximum heating rate, total heat load, and deceleration loads experienced by the spacecraft during entry [1-3]. ADEPT and the Hypersonic Inflatable Aerodynamic Decelerator (HIAD) [4] share the approach of stowing the entry system in the shroud of the launch vehicle and deploying it to a much larger diameter prior to entry. The ADEPT concept provides a low ballistic coefficient for planetary entry by employing an umbrella-like deployable structure consisting of ribs, struts and a fabric cover that form an aerodynamic decelerator capable of undergoing hypersonic flight. The ADEPT "skin" is a 3-D woven carbon cloth that serves as a thermal protection system (TPS) and as a structural surface that transfers aerodynamic forces to the underlying ribs [5]. This paper focuses on design activities associated with integrating ADEPT components (cloth, ribs, struts and mechanisms) into a system that can function across all configurations and environments of a typical mission concept: stowed during launch, in-space deployment, entry, descent, parachute deployment and separation from the landing payload. The baseline structures and mechanisms were selected via trade studies conducted during the summer and fall of 2012. They are now being incorporated into the design of a ground test article (GTA) that will be fabricated in 2013. It will be used to evaluate retention of the stowed configuration in a launch environment, mechanism operation for release, deployment and locking, and static strength of the deployed decelerator. Of particular interest are the carbon cloth interfaces, underlying hot structure, (Advanced Carbon- Carbon ribs) and other structural components (nose cap, struts, and main body) designed to withstand the pressure and extremely high heating experienced during planetary entry.

Yount, Bryan C.↗