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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 973 records · Page 54
All sourcesNASA NTRSDOE OSTI
NASA NTRS2002

Studies of Gas-Particle Interactions in a Microgravity Flow Cell

The ability to transport particulate materials predictably and efficiently using a flowing gas is likely to play an important role in the development of lunar and Martian environments that are hospitable to humans. Lunar soil contains significant amounts of oxygen, hydrogen and other critical materials that are chemically bound in various minerals. Through appropriate processing, these resources may be recovered for use in propulsion, life support systems and mining operations. Similarly, it is believed that Martian soil contains significant amounts of water which can be electrolyzed into oxygen and hydrogen, again for propellants and life support. The transport of such granular soils from where they are mined and between stages of their processing is likely to involve pneumatic transport carried out in systems of pipes using flows of the liberated gases. On earth, the transport and processing of solid materials are also crucial in a number of applications from the chemical, mining, power and oil industries. For these flows, an appreciation has recently developed for the influence of collisional interactions among particles, both in suspensions where the flow is laminar and turbulent. Collisions between such particles can transfer a significant amount of momentum within the flow and at the boundaries. This provides an additional resistance to the passage of the gas, but it also introduces a mechanism that promotes more homogeneous flows and, at least in small-diameter pipes, may forestall the development of clusters.

Louge, Michel Y.↗
NASA NTRS2005

Advanced Ceramic Matrix Composites (CMCs) for High Temperature Applications

Advanced ceramic matrix composites (CMCs) are enabling materials for a number of demanding applications in aerospace, energy, and nuclear industries. In the aerospace systems, these materials are being considered for applications in hot sections of jet engines such as the combustor liner, vanes, nozzle components, nose cones, leading edges of reentry vehicles, and space propulsion components. Applications in the energy and environmental industries include radiant heater tubes, heat exchangers, heat recuperators, gas and diesel particulate filters, and components for land based turbines for power generation. These materials are also being considered for use in the first wall and blanket components of fusion reactors. In the last few years, a number of CMC components have been developed and successfully tested for various aerospace and ground based applications. However, a number of challenges still remain slowing the wide scale implementation of these materials. They include robust fabrication and manufacturing, assembly and integration, coatings, property modeling and life prediction, design codes and databases, repair and refurbishment, and cost. Fabrication of net and complex shape components with high density and tailorable matrix properties is quite expensive, and even then various desirable properties are not achievable. In this presentation, a number of examples of successful CMC component development and testing will be provided. In addition, critical need for robust manufacturing, joining and assembly technologies in successful implementation of these systems will be discussed.

Singh, M.↗
NASA NTRS2017

Nuclear Cryogenic Propulsion Stage (NCPS) Fuel Element Testing in the Nuclear Thermal Rocket Element Environmental Simulator (NTREES)

To support the on-going nuclear thermal propulsion effort, a state-of-the-art non nuclear experimental test setup has been constructed to evaluate the performance characteristics of candidate fuel element materials and geometries in representative environments. The facility to perform this testing is referred to as the Nuclear Thermal Rocket Element Environment Simulator (NTREES). Last year NTREES was successfully used to satisfy a testing milestone for the Nuclear Cryogenic Propulsion Stage (NCPS) project and met or exceeded all required objectives.

Emrich, William J., Jr.↗
NASA NTRS2012

Metals and Oxygen Mining from Meteorites, Asteroids and Planets using Reusable Ionic Liquids

In order for humans to explore beyond Low Earth Orbit both safely and economically, it will be essential to learn how to make use of in situ materials and energy in an environment much different than on earth. Precursor robotic missions will be necessary to determine what resources will be available and to demonstrate the capabilities for their use. To that end, we have recently been studying acidic Ionic Liquid (IL) systems for use in a low temperature (< 200 C) process to solubilize regolith, and to extract, as water, the oxygen available in metal oxides. Using this method, we have solubilized lunar regolith simulant (JSC-1A), as well as extraterrestrial materials in the form of meteorites, and have extracted up to 80% of the available oxygen. Moreover, by using a hydrogen gas electrode, we have shown that the IL can be regenerated at the anode and metals (e.g. iron) can be plated onto the cathode. These results indicate that IL processing is an excellent candidate for extracting oxygen in situ, for life support and propulsion, and for extracting metals to be used as feedstock in fabrication processes. We have obtained small amounts of meteorite materials believed by meteoriticists to have originated from our moon, Mars, and the asteroid Vesta, and were able to solubilize those using acidic IL systems. From the Vesta meteorite, we were able to extract about 60% of the available oxygen as water. As far as is known, this is the first time that extraterrestrial/earth hybrid water has been obtained. NMR analysis provided proof that the liquid retrieved is indeed water. We have also been able to electro-plate nickel and iron contained in meteorite material. By varying voltage they can be plated separately (electro-winning), and we plan to soon have sufficient quantities to form usable parts utilizing the additive manufacturing process.

Karr, Laurel J.↗
NASA NTRS1989

Enabling technologies research and development structures

The technology-development areas of most critical importance to the definition of the NASP vehicle's airframe and integrated propulsion systems are discussed with a view to the progress made to date and the prospects for the expansion of a definitive NASP design data base on materials, structures, etc. It is necessary to achieve a very low structural-mass fraction, to withstand 6000 F radiation equilibrium fuselage nosecap temperatures, to manage an extensive active cooling network for both airframe and propulsion system capable of dissipating 10,000 BTU/sq ft-sec thermal fluxes, to maintain effective hot-gas sealing, and to manufacture high temperature effectiveness-retaining control surfaces. An account is given of successes thus far achieved.

Davis, John G., Jr.↗
NASA NTRS1996

Development of a material property database on selected ceramic matrix composite materials

Ceramic Matrix Composites, with fiber/whisker/particulate reinforcement, possess the attractive properties of ceramics such as high melting temperature, high strength and stiffness at high temperature, low density, excellent environmental resistance, combined with improved toughness and mechanical reliability. These unique properties have made these composites an enabling technology for thermomechanically demanding applications in high temperature, high stress and aggressive environments. On a broader scale, CMC's are anticipated to be applicable in aircraft propulsion, space propulsion, power and structures, in addition to ground based applications. However, it is also true that for any serious commitment of the material toward any of the intended critical thermo-mechanical applications to materialize, vigorous research has to be conducted for a thorough understanding of the mechanical and thermal behavior of CMC's. The high technology of CMC'S is far from being mature. In view of this growing need for CMC data, researchers all over the world have found themselves drawn into the characterization of CMC's such as C/SiC, SiC/SiC, SiC/Al203, SiC/Glass, SiC/C, SiC/Blackglas. A significant amount of data has been generated by the industries, national laboratories and educational institutions in the United States of America. NASA/Marshall Space Flight Center intends to collect the 'pedigreed' CMC data and store those in a CMC database within MAPTIS (Materials and Processes Technical Information System). The task of compilation of the CMC database is a monumental one and requires efforts in various directions. The project started in the form of a summer faculty fellowship in 1994 and has spilled into the months that followed and into the summer faculty fellowship of 1995 and has the prospect of continuing into the future for a healthy growth, which of course depends to a large extent on how fast CMC data are generated. The 10-week long summer fellowship has concentrated, basically, on establishing the procedure for a smooth transfer of data into a CMC database on MAPTIS which is a vital part of the following broader picture of the project.

Mahanta, Kamala↗
NASA NTRS2005

Fifth International Symposium on Liquid Space Propulsion

Contents include the fiollowing: Theme: Life-life Combustion Devices Technology. Technical Sessions: International Perspectives. System Level Effects. Component Level Processes. Material Considerations. Design Environments -- Predictions. Injector Design Technology. Design Environments -- Measurements. Panel Discussion: Views on future research and development needs and Symposium observations. Aquarium Welcome and Southern Belle Riverboat Recognition Banquet evening events.

Garcia, R.↗
NASA NTRS1988

Spray automated balancing of rotors: Methods and materials

The work described consists of two parts. In the first part, a survey is performed to assess the state of the art in rotor balancing technology as it applies to Army gas turbine engines and associated power transmission hardware. The second part evaluates thermal spray processes for balancing weight addition in an automated balancing procedure. The industry survey reveals that: (1) computerized balancing equipment is valuable to reduce errors, improve balance quality, and provide documentation; (2) slow-speed balancing is used exclusively, with no forseeable need for production high-speed balancing; (3) automated procedures are desired; and (4) thermal spray balancing is viewed with cautious optimism whereas laser balancing is viewed with concern for flight propulsion hardware. The FARE method (Fuel/Air Repetitive Explosion) was selected for experimental evaluation of bond strength and fatigue strength. Material combinations tested were tungsten carbide on stainless steel (17-4), Inconel 718 on Inconel 718, and Triballoy 800 on Inconel 718. Bond strengths were entirely adequate for use in balancing. Material combinations have been identified for use in hot and cold sections of an engine, with fatigue strengths equivalent to those for hand-ground materials.

Smalley, Anthony J.↗
NASA NTRS1998

High Speed Research: Propulsion Project Accomplishments

This past year has been one of great accomplishment for the propulsion element of NASA's High Speed Research (HSR) Program. The HSR Program is a NASA/industry partnership to develop the high-risk/high-payoff airframe and propulsion technologies applicable to a second-generation supersonic commercial transport, or High Speed Civil Transport (HSCT). The propulsion element, which also involves industry partners, is managed by the NASA Lewis Research Center. These technologies will contribute greatly to U.S. industry's ability to make an informed product launch decision for an HSCT vehicle. Specific NASA Lewis accomplishments in 1997 include: 1. Small-scale combustor sector tests conducted in Lewis' Engine Research Building contributed to the evolution of approaches to developing a combustor with ultralow NOx emissions. 2. Components were tested in Lewis' CE-9 facility (in Lewis' Engine Research Building) to assess the performance of candidate ceramic matrix composite (CMC) materials in this realistic combustion environment. Test results were promising, and acceptable levels of structural durability were demonstrated for the ceramic matrix composite material tested. Ceramic matrix composites continue to show great promise for use in HSCT combustor liners. 3. Engine emissions tests in Lewis' Propulsion Systems Laboratory provided insight into other classes of emissions (e.g., particulates and aerosols) which will be important to control in HSCT propulsion system designs. 4. Small-scale nozzle tests conducted in Lewis' Aero-Acoustic Propulsion Laboratory are contributing to the design of a low-noise, high-performance mixer/ejector nozzle configuration for HSCT engines. Over 18,000 hours of durability testing were completed in Lewis' materials laboratories to evaluate superalloy and g-titanium aluminide performance for HSCT nozzle applications. A two-dimensional supersonic inlet concept was tested in Lewis' 10- by 10-Foot Supersonic Wind Tunnel. The extensive database and the knowledge gained contributed to the selection of a two-dimensional inlet as the preferred inlet concept for the HSR Program.

Shaw, Robert J.↗
NASA NTRS2008

Analysis of International Space Station Materials on MISSE-3 and MISSE-4

For high-temperature applications (> 2,000 C) such as solid rocket motors, hypersonic aircraft, nuclear electric/thermal propulsion for spacecraft, and more efficient jet engines, creep becomes one of the most important design factors to be considered. Conventional creep-testing methods, where the specimen and test apparatus are in contact with each other, are limited to temperatures ~1,700 deg. C. Development of alloys for higher-temperature applications is limited by the availability of testing methods at temperatures above 2000 C. Development of alloys for applications requiring a long service life at temperatures as low as 1500 C, such as the next generation of jet turbine superalloys, is limited by the difficulty of accelerated testing at temperatures above 1700 0c. For these reasons, a new, non-contact creep-measurement technique is needed for higher temperature applications. A new non-contact method for creep measurements of ultra-high-temperature metals and ceramics has been developed and validated. Using the electrostatic levitation (ESL) facility at NASA Marshall Space Flight Center, a spherical sample is rotated quickly enough to cause creep deformation due to centrifugal acceleration. Very accurate measurement of the deformed shape through digital image analysis allows the stress exponent n to be determined very precisely from a single test, rather than from numerous conventional tests. Validation tests on single-crystal niobium spheres showed excellent agreement with conventional tests at 1985 C; however the non-contact method provides much greater precision while using only about 40 milligrams of material. This method is being applied to materials including metals and ceramics for noneroding throats in solid rockets and next-generation superalloys for turbine engines. Recent advances in the method and the current state of these new measurements will be presented.

Finckenor, Miria M.↗
NASA NTRS2010

Development and Life Prediction of Erosion Resistant Turbine Low Conductivity Thermal Barrier Coatings

Future rotorcraft propulsion systems are required to operate under highly-loaded conditions and in harsh sand erosion environments, thereby imposing significant material design and durability issues. The incorporation of advanced thermal barrier coatings (TBC) in high pressure turbine systems enables engine designs with higher inlet temperatures, thus improving the engine efficiency, power density and reliability. The impact and erosion resistance of turbine thermal barrier coating systems are crucial to the turbine coating technology application, because a robust turbine blade TBC system is a prerequisite for fully utilizing the potential coating technology benefit in the rotorcraft propulsion. This paper describes the turbine blade TBC development in addressing the coating impact and erosion resistance. Advanced thermal barrier coating systems with improved performance have also been validated in laboratory simulated engine erosion and/or thermal gradient environments. A preliminary life prediction modeling approach to emphasize the turbine blade coating erosion is also presented.

Zhu, Dongming↗
NASA NTRS1999

Technical Considerations for Advanced Propulsion Systems

This presentation reviews concerns involving advanced propulsion systems. The problems involved with the use of Am-242m, is that it has a high "eta" plus an order of magnitude larger fission cross section than other fissionable materials, and that it is extremely rare. However other americium isotopes are much more common, but extremely effective isotopic separation is required. Deuterium-Tritium fusion is also not attractive for space propulsion applications. Because the pulsed systems cannot breed adequate amounts of tritium and it is difficult and expensive to bring tritium from Earth. The systems that do breed tritium have severely limited performance. However, other fusion processes should still be evaluated. Another problem with advanced propellants is that inefficiencies in converting the total energy generated into propellant energy can lead to tremendous heat rejection requirements. Therefore Many. advanced propulsion concepts benefit greatly from low-mass radiators.

Houts, Michael G.↗
NASA NTRS2012

Advanced Aero-Propulsive Mid-Lift-to-Drag Ratio Entry Vehicle for Future Exploration Missions

NASA is currently looking well into the future toward realizing Exploration mission possibilities to destinations including the Earth-Moon Lagrange points, Near-Earth Asteroids (NEAs) and the Moon. These are stepping stones to our ultimate destination Mars. New ideas will be required to conquer the significant challenges that await us, some just conceptions and others beginning to be realized. Bringing these ideas to fruition and enabling further expansion into space will require varying degrees of change, from engineering and integration approaches used in spacecraft design and operations, to high-level architectural capabilities bounded only by the limits of our ideas. The most profound change will be realized by paradigm change, thus enabling our ultimate goals to be achieved. Inherent to achieving these goals, higher entry, descent, and landing (EDL) performance has been identified as a high priority. Increased EDL performance will be enabled by highly-capable thermal protection systems (TPS), the ability to deliver larger and heavier payloads, increased surface access, and tighter landing footprints to accommodate multiple asset, single-site staging. In addition, realizing reduced cost access to space will demand more efficient approaches and reusable launch vehicle systems. Current operational spacecraft and launch vehicles do not incorporate the technologies required for these far-reaching missions and goals, nor what is needed to achieve the desired launch vehicle cost savings. To facilitate these missions and provide for safe and more reliable capabilities, NASA and its partners will need to make ideas reality by gaining knowledge through the design, development, manufacturing, implementation and flight testing of robotic and human spacecraft. To accomplish these goals, an approach is recommended for integrated development and implementation of three paradigm-shifting capabilities into an advanced entry vehicle system with additional application to launch vehicle stage return, thus making ideas reality. These paradigm shifts include the technology maturation of advanced flexible thermal protection materials onto mid lift-to-drag ratio entry vehicles, the development of integrated supersonic aero-propulsive maneuvering, and the implementation of advanced asymmetric launch shrouds. These paradigms have significant overlap with launch vehicle stage return already being developed by the Air Force and several commercial space efforts. Completing the realization of these combined paradigms holds the key to a high-performing entry vehicle system capability that fully leverages multiple technology benefits to accomplish NASA's Exploration missions to atmospheric planetary destinations.

Campbell, C. H.↗
NASA NTRS2001

General Multimechanism Reversible-Irreversible Time-Dependent Constitutive Deformation Model Being Developed

Since most advanced material systems (for example metallic-, polymer-, and ceramic-based systems) being currently researched and evaluated are for high-temperature airframe and propulsion system applications, the required constitutive models must account for both reversible and irreversible time-dependent deformations. Furthermore, since an integral part of continuum-based computational methodologies (be they microscale- or macroscale-based) is an accurate and computationally efficient constitutive model to describe the deformation behavior of the materials of interest, extensive research efforts have been made over the years on the phenomenological representations of constitutive material behavior in the inelastic analysis of structures. From a more recent and comprehensive perspective, the NASA Glenn Research Center in conjunction with the University of Akron has emphasized concurrently addressing three important and related areas: that is, 1) Mathematical formulation; 2) Algorithmic developments for updating (integrating) the external (e.g., stress) and internal state variables; 3) Parameter estimation for characterizing the model. This concurrent perspective to constitutive modeling has enabled the overcoming of the two major obstacles to fully utilizing these sophisticated time-dependent (hereditary) constitutive models in practical engineering analysis. These obstacles are: 1) Lack of efficient and robust integration algorithms; 2) Difficulties associated with characterizing the large number of required material parameters, particularly when many of these parameters lack obvious or direct physical interpretations.

Saleeb, A. F.↗
NASA NTRS1986

The effects of energetic proton bombardment on polymeric materials: Experimental studies and degradation models

This report describes 3 MeV proton bombardment experiments on several polymeric materials of interest to NASA carried out on the Tandem Van De Graff Accelerator at the California Institute of Technology's Kellogg Radiation Laboratory. Model aromatic and aliphatic polymers such as poly(1-vinyl naphthalene) and poly(methyl methacrylate), as well as polymers for near term space applications such as Kapton, Epoxy and Polysulfone, have been included in this study. Chemical and physical characterization of the damage products have been carried out in order to develop a model of the interaction of these polymers with the incident proton beam. The proton bombardment methodology developed at the Jet Propulsion Laboratory and reported here is part of an ongoing study on the effects of space radiation on polymeric materials. The report is intended to provide an overview of the mechanistic, as well as the technical and experimental, issues involved in such work rather than to serve as an exhaustive description of all the results.

Coulter, D. R.↗
NASA NTRS1975

The NASA research program on propulsion for supersonic cruise aircraft

Since 1972 NASA has pursued a program aimed at advancing the technology and establishing a data base appropriate for the possible future development of supersonic cruise aircraft. This paper briefly reviews the objectives and status of the propulsion portion of the program. Building upon a continuing series of propulsion system studies, research activities are under way in noise and pollution reduction, inlet stability, and materials.

Weber, R. J.↗
NASA NTRS1985

Compatibility of grain-stabilized platinum with candidate propellants for resistojets

Resistojets are candidates for space station auxiliary propulsion, and should be characterized by both long life and multipropellant operations, requirements limited by available materials. Grain stabilized platinum is examined for use as a resistojet thruster material. Use of platinum in other applications indicates it can be used at moderately high temperatures for extended periods of time. Past results indicate that grain-stabilized platinum should be sufficiently inert in candidate propellant environments. Therefore, compatibility of platinum-yttria (P/Y2O3) and platinum-zirconia (Pt/ZrO2) with carbon dioxide, methane, hydrogen and ammonia is examined. A series of 1000 hr tests in CO2, H2, and NH3 is conducted at 1400 C and a series of 1000 hr tests in CH4 is conducted at about 500 C. Scanning electron microscopy, Auger electron spectroscopy and depth profiling analysis are then used to determine the effects of propellants on the material surface, to evaluate possible material contamination and to evaluate grain growth. The results indicate that there is carbon deposition on the surface of the Pt/Y2O3 and Pt/ZrO2 in both the CO2 and CH4 environments. In the H2 environment, the Pt/Y2O3 and Pt/ZrO2 specimen surfaces are roughened. After exposure to the NH3 environment, the Pt/Y2O3 and Pt/ZrO2 are roughened and pitted over the entire heated area with some pitted areas along the grain boundaries. SEM photos show grain growth in cross-sectional views of all the Pt/Y2O3 samples and the Pt/ZrO2 samples, except that tested in methane. Mass loss measurements indicate that Pt/Y2O3 and Pt/ZrO2 would last in excess of 200,000 hr in each propellant environment. However, in NH3 both Pt/Y2O3 and Pt/ZrO2 are severely pitted, with voids up to 50 percent into the material. Pt/Y2O3 and Pt/ZrO2 are not recommended for high temperature service in NH3.

Whalen, M. V.↗