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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 sourcesNASA NTRSDOE OSTI
NASA NTRS1989

Estimated performance and future potential of solar dynamic and photovoltaic power systems for selected LEO and HEO missions

Solar Photo Voltaic (PV) and thermal dynamic power systems for application to selected Low Earth Orbit (LEO) and High Eccentric Orbit (Energy) (HEO) missions are characterized in the regime 7 to 35 kWe. Input parameters to the characterization are varied corresponding to anticipated introduction of improved or new technologies. Comparative assessment is made between the two power system types utilizing newly emerging technologies in cells and arrays, energy storage, optical surfaces, heat engines, thermal energy storage, and thermal management. The assessment is made to common ground rules and assumptions. The four missions (space station, sun-synchronous, Van Allen belt and GEO) are representative of the anticipated range of multi-kWe earth orbit missions. System characterizations include all required subsystems, including power conditioning, cabling, structure, to deliver electrical power to the user. Performance is estimated on the basis of three different levels of component technology: (1) state-of-art, (2) near-term, and (3) advanced technologies. These range from planar array silicon/IPV nickel hydrogen batteries and Brayton systems at 1000 K to thin film GaAs with high energy density secondary batteries or regenerative fuel cells and 1300 K Stirling systems with ultra-lightweight concentrators and radiators. The system estimates include design margin for performance degradations from the known environmental mechanisms (micrometeoroids and space debris, atomic oxygen, electron and proton flux) which are modeled and applied depending on the mission. The results give expected performance, mass and drag of multi-kWe earth orbiting solar power systems and show how overall system figures of merit will improve as new component technologies are incorporated.

Bents, David J.↗
NASA NTRS2015

IAF 15 Draft Paper

With the International Space Station Program transition from assembly to utilization, focus has been placed on the optimization of essential resources. This includes resources both resupplied from the ground and also resources produced by the ISS. In an effort to improve the use of two of these, the ISS Engineering teams, led by the ISS Program Systems Engineering and Integration Office, undertook an effort to modify the techniques use to perform several key on-orbit events. The primary purposes of this endeavor was to make the ISS more efficient in the use of the Russian-supplied fuel for the propulsive attitude control system and also to minimize the impacts to available ISS power due to the positioning of the ISS solar arrays. Because the ISS solar arrays are sensitive to several factors that are present when propulsive attitude control is used, they must be operated in a manner to protect them from damage. This results in periods of time where the arrays must be positioned, rather than autonomously tracking the sun, resulting in negative impacts to power generated by the solar arrays and consumed by both the ISS core systems and payload customers. A reduction in the number and extent of the events each year that require the ISS to use propulsive attitude control simultaneously accomplishes both these goals. Each instance where the ISS solar arrays normal sun tracking mode must be interrupted represent a need for some level of powerdown of equipment. As the magnitude of payload power requirements increases, and the efficiency of the ISS solar arrays decreases, these powerdowns caused by array positioning, will likely become more significant and could begin to negatively impact the payload operations. Through efforts such as this, the total number of events each year that require positioning of the arrays to unfavorable positions for power generation, in order to protect them against other constraints, are reduced. Optimization of propulsive events and transitioning some of them to non-propulsive CMG control significantly reduces propellant usage on the ISS leading to the reduction of the propellant delivery requirement. This results in move available upmass that can be used for delivering critical dry cargo, additional water, air, crew supplies and science experiments.

Menkin, Evgeny↗
NASA NTRS1995

Combustion Module 1: Spacelab Racks Integrated at the Lewis Research Center for the First Time

The Combustion Module-1 (CM-1), NASA's largest (over 1800 lb) and one of the most sophisticated combustion experiments ever to fly on the Spacelab, will be carried on the first Microgravity Science Laboratory (MSL-1) mission aboard the space shuttle flight STS-84 in April 1997. The CM-1 project is a stepping stone to the space station era, because the hardware can support multiple investigators on the same mission and can be integrated at user locations and shipped to the launch site. CM-1 is being developed to accommodate microgravity combustion experiments that are designed to help explain and predict the behavior of combustion processes. Although the two principal investigators for CM-1 are both studying combustion processes, their investigations are quite different. Professor Paul D. Ronney of the University of Southern California will examine the Structures of Flame Balls at Low Lewis Numbers (SOFBALL), in which a variety of fuel-lean gaseous mixtures fill the combustion chamber and are ignited. Professor Gerard M. Faeth of the University of Michigan will investigate Laminar Soot Processes (LSP) by studying the key properties of burning gas jets of fuel, employing different fuels and nozzle sizes.

Source record↗
NASA NTRS2000

Microgravity Platforms

The world's space agencies have been conducting microgravity research since the beginning of space flight. Initially driven by the need to understand the impact of less than- earth gravity physics on manned space flight, microgravity research has evolved into a broad class of scientific experimentation that utilizes extreme low acceleration environments. The U.S. NASA microgravity research program supports both basic and applied research in five key areas: biotechnology - focusing on macro-molecular crystal growth as well as the use of the unique space environment to assemble and grow mammalian tissue; combustion science - focusing on the process of ignition, flame propagation, and extinction of gaseous, liquid, and solid fuels; fluid physics - including aspects of fluid dynamics and transport phenomena; fundamental physics - including the study of critical phenomena, low-temperature, atomic, and gravitational physics; and materials science - including electronic and photonic materials, glasses and ceramics, polymers, and metals and alloys. Similar activities prevail within the Chinese, European, Japanese, and Russian agencies with participation from additional international organizations as well. While scientific research remains the principal objective behind these program, all hope to drive toward commercialization to sustain a long range infrastructure which .benefits the national technology and economy. In the 1997 International Space Station Commercialization Study, conducted by the Potomac Institute for Policy Studies, some viable microgravity commercial ventures were identified, however, none appeared sufficiently robust to privately fund space access at that time. Thus, government funded micro gravity research continues on an evolutionary path with revolutionary potential.

Del Basso, Steve↗
DOE OSTI2022

Liquid Hydrogen Heavy-Duty Vehicle Safety Review and Refueling Facility Design

Liquid hydrogen (LH 2 ) used as a fuel onboard a heavy-duty vehicle can result in increased storage capacity and faster refueling relative to compressed gas. However, there are concerns about hydrogen losses from boil-off, potential safety issues, gaps in codes and standards for cryogenic hydrogen fuel, and technical challenges with LH 2 systems for widespread transportation applications. A failure modes and effects analysis (FMEA), a safety codes and standards review, and a design review of the onboard liquid hydrogen system for a heavy-duty vehicle identified some of these potential safety issues and gaps in the codes and standards. The FMEA identified some medium and low risk failure points of the conceptual design, and the design review identified how carefully pressure relief needs to be considered for LH 2 systems. In addition, a conceptual design for a LH 2 refueling station was developed. Rough capital costs for the refueling station design were $\$1 million$ and the layout occupied approximately 13,000 ft 2 . These results can be used to inform future designs and analyses for LH 2 heavy-duty vehicles.

08 HYDROGEN↗
NASA NTRS2015

Meteoroid-Induced Anomalies on Spacecraft

Many programs/projects use a simple meteoroid environment based on Grun's 1985 paper or the old NASA space station spec in their design and risk assessments. These models, which are omni directional and mono-­velocity, bear little resemblance to the actual meteoroid environment, which is sun-fixed, very directional, and which has a complex speed distribution varying by source and particle size. As a result, the simple meteoroid models lead to estimates that underestimate the spacecraft/vehicle risk by a factor of 2 or more. In addition, programs often over-emphasize the risk posed by meteor showers, which typically account for less than ten percent of the meteoroid risk over the vehicle lifetime. Fueled by popular media, the emphasis on meteor showers (the risks from which can usually be mitigated operationally) can lead to ambivalence to the real risk driver, which is the sporadic background.

Cooke, William J.↗
NASA NTRSDate not supplied

Design of Space Systems to Enable In-space Assembly and Servicing

For several decades, NASA has employed in-space systems to enhance the performance and extend the useful life of operational orbital assets. In at least one case, an operational mission was not only enhanced, but enabled – the International Space Station was made possible by crewed and robotic in-space assembly, and continues to support installation and operation of new science and technology payloads. In several cases (Hubble Space Telescope, Intelsat 401, Westar and Palapa), major operational assets were rescued or repaired soon after launch when otherwise mission-ending anomalies occurred or were detected. In addition to the original rescue, Hubble was upgraded four times, enabling high-demand, world class science over four decades. More recently, two Northrop Grumman Mission Extension Vehicles have captured two Intelsat spacecraft near the end of their life and fuel capacity, to take over maneuvering duties. In spite of these recent operational achievements, and with the exception of large human exploration vehicles and large space telescopes, space architects rarely consider in-orbit servicing and assembly capabilities in their future planning. Technologies such as multi-launch mission architectures (and rendezvous and proximity operations systems), docking systems, external robotics, advanced tools, modular systems and structures, and fluid transfer systems are available today to support these missions. In-space manufacturing will soon be operational to enable resilient missions that recover from on-orbit failures, and expand the utilization of space. We envision a future that includes these capabilities, and discuss the cultural, engineering, and technological challenges to achieving this vision. We discuss the vision, the proverbial chicken and the egg (which came first, the serviceable spacecraft or the servicer?), the cost, risk, and perceptions thereof of in-space operations, a “spectrum” of cooperative servicing design considerations, and the current status of the space industry’s slow but steady march to widespread operational use of on-orbit servicing, assembly, and manufacturing.

Bo Naasz↗
DOE OSTI2021

North Dakota CarbonSAFE Baseline Microgravity Survey, Lessons Learned

Conference presentation at American Geophysical Union (AGU) Fall Meeting, New Orleans, LA and virtual, December 13–17, 2021. The team conducted a baseline microgravity survey near Minnkota Power Cooperative’s Milton R. Young power station, south of Center, North Dakota, as a part of the North Dakota CarbonSAFE (Carbon Storage Assurance Facility Enterprise) geophysical activities. The goal of this survey was to assess whether microgravity would be an appropriate technique to monitor CO 2 stored at this site.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2021

Methane Exhaust Measurements at Gathering Compressor Stations in the United States

Unburned methane entrained in exhaust from natural gas-fired compressor engines (“combustion slip”) can account for a substantial portion of station-level methane emissions. A novel in-stack, tracer gas method was coupled with Fourier transform infrared (FTIR) species measurements to quantify combustion slip from natural gas compressor engines at 67 gathering and boosting stations owned or managed by nine “study partner” operators in 11 U.S. states. The mean methane emission rate from 63 four-stroke, lean-burn (4SLB) compressor engines was 5.62 kg/h (95% CI = 5.15–6.17 kg/h) and ranged from 0.3 to 12.6 kg/h. The mean methane emission rate from 39 fourstroke, rich-burn (4SRB) compressor engines was 0.40 kg/h (95% CI = 0.37– 0.42 kg/h) and ranged from 0.01 to 4.5 kg/h. Study results for 4SLB engines were lower than both the U.S. EPA compilation of air pollutant emission factors (AP-42) and Inventory of U.S. Greenhouse Gas Emissions and Sinks (GHGI) by 8 and 9%, respectively. Study results for 4SRB engines were 43% of the AP-42 emission factor and 8% of the GHGI emission factor, the latter of which does not distinguish between engine types. Total annual combustion slip from the U.S. natural gas gathering and boosting sector was modeled using measured emission rates and compressor unit counts from the U.S. EPA Greenhouse Gas Reporting Program. Modeled results [328 Gg/y (95% CI = 235–436 Gg/y) of unburned methane] would account for 24% (95% CI = 17–31%) of the 1391 Gg of methane emissions for “Gathering and Boosting Stations”, or 6% of the net emissions for “Natural Gas Systems” (5598 Gg) as reported in the 2020 U.S. EPA GHGI. In conclusion, gathering and boosting combustion slip emissions reported in the 2020 GHGI (374 Gg) fall within the uncertainty of this model.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

AI-based design of a nuclear reactor core

The authors developed an artificial intelligence (AI)-based algorithm for the design and optimization of a nuclear reactor core based on a flexible geometry and demonstrated a 3× improvement in the selected performance metric: temperature peaking factor. The rapid development of advanced, and specifically, additive manufacturing (3-D printing) and its introduction into advanced nuclear core design through the Transformational Challenge Reactor program have presented the opportunity to explore the arbitrary geometry design of nuclear-heated structures. The primary challenge is that the arbitrary geometry design space is vast and requires the computational evaluation of many candidate designs, and the multiphysics simulation of nuclear systems is very time-intensive. Therefore, the authors developed a machine learning-based multiphysics emulator and evaluated thousands of candidate geometries on Summit, Oak Ridge National Laboratory’s leadership class supercomputer. The results presented in this work demonstrate temperature distribution smoothing in a nuclear reactor core through the manipulation of the geometry, which is traditionally achieved in light water reactors through variable assembly loading in the axial direction and fuel shuffling during refueling in the radial direction. The conclusions discuss the future implications for nuclear systems design with arbitrary geometry and the potential for AI-based autonomous design algorithms.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
NASA NTRS2003

Electronic nose for space program applications

The ability to monitor air contaminants in the shuttle and the International Space Station is important to ensure the health and safety of astronauts, and equipment integrity. Three specific space applications have been identified that would benefit from a chemical monitor: (a) organic contaminants in space cabin air; (b) hypergolic propellant contaminants in the shuttle airlock; (c) pre-combustion signature vapors from electrical fires. NASA at Kennedy Space Center (KSC) is assessing several commercial and developing electronic noses (E-noses) for these applications. A short series of tests identified those E-noses that exhibited sufficient sensitivity to the vapors of interest. Only two E-noses exhibited sufficient sensitivity for hypergolic fuels at the required levels, while several commercial E-noses showed sufficient sensitivity of common organic vapors. These E-noses were subjected to further tests to assess their ability to identify vapors. Development and testing of E-nose models using vendor supplied software packages correctly identified vapors with an accuracy of 70-90%. In-house software improvements increased the identification rates between 90 and 100%. Further software enhancements are under development. Details on the experimental setup, test protocols, and results on E-nose performance are presented in this paper along with special emphasis on specific software enhancements. c2003 Elsevier Science B.V. All rights reserved.

Air Pollution, Indoor/analysis↗
NASA NTRS2007

A General Approach to the Geostationary Transfer Orbit Mission Recovery

This paper discusses recovery scenarios for geosynchronous satellites injected in a non-nominal orbit due to a launcher underperformance. The theory on minimum-fuel orbital transfers is applied to develop an operational tool capable to design a recovery mission. To obtain promising initial guesses for the recovery three complementary techniques are used: p-optimized impulse function contouring, a numerical impulse function minimization and the solutions to the switching equations. The tool evaluates the feasibility of a recovery with the on-board propellant of the spacecraft and performs the complete mission design. This design takes into account for various mission operational constraints such as e.g., the requirement of multiple finite-duration burns, third-body orbital perturbations, spacecraft attitude constraints and ground station visibility. In a final case study, we analyze the consequences of a premature breakdown of an upper rocket stage engine during injection on a geostationary transfer orbit, as well as the possible recovery solution with the satellite on-board propellant.

Faber, Nicolas↗
DOE OSTI2021

(Paper) TRIPWIRE: Multi-modal Distributed Sensing For Repository Verification

Underground geological repositories for storing used nuclear fuel are being planned and developed around the world. Research is being performed to understand technical aspects of sealing entombed materials and underground repositories to ensure the radiological and nuclear materials remain contained. To support safeguards verification for these facilities research at Idaho National Laboratory (INL) is underway to develop and demonstrate a multi-modal sensor system, TRIPWIRE, for containment verification in inaccessible radiological and nuclear waste repositories. The TRIPWIRE system will continuously monitor ionizing radiation and electromagnetic fields in the vicinity of emplaced nuclear materials buried in a repository, reporting on disturbances with a real-time alarm control station. The system will use long-length scintillating fiber bundles (SFBs) to perform area radiation monitoring; these will be coupled to kilometer-scale multimodal optical communication fibers – all light sensors and electronic components used with this system will be located above ground. Electromagnetic fields, and changes in local dielectric conditions caused by intrusion and soil movement, will be monitored using commercial grade, ported "leaky" coaxial cables (PCCs), with control electronics also located above ground. Tamper-indicating self-diagnostic assessments will be done using optical and electronic time domain reflectometry in the SFBs and PCCs, respectively. The result will be a long, kilometer-scale multi-modal SFB-PCC system. Simulation and modeling are being used to inform the work and a demonstration of the system's utility is planned at a nuclear storage facility in the future.

98 - NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL↗
NASA NTRS1995

Microgravity combustion of dust clouds: Quenching distance measurements

The current level of physical understanding of dust combustion phenomena is still in a rudimentary state compared with the understanding of gas combustion processes. The reason for such a lack of fundamental understanding is partially based on the complexity of multiphase combustion and the enormous diversity of chemical-physical properties of heterogeneous combustible mixtures but is largely due to difficulties in the experimental investigation of dust combustion. The influence of gravity on a dust suspension is the main reason. First of all, when particulates (either solid particles or liquid droplets) with a characteristic size of the order of tens of microns are suspended, they rapidly settle in the gravitational field. To maintain a particulate suspension for a time duration adequate to carry out combustion experiments invariably requires continuous convection of particulates at or in excess of the gravitational settling velocity. Of necessity, this makes the experiments turbulent in character and makes it impossible to study laminar dust flames. For particle sizes of the order of microns a stable laminar dust flow can be maintained only for relatively small dust concentrations (e.g., for low fuel equivalence ratios) at normal gravity conditions. High dust loading leads to gravitational instability of the dust cloud and to the formation of recirculation cells in a dust suspension in a confined volume, or to the rapid sedimentation of the dense dust cloud as a whole in an unconfined volume. In addition, many important solid fuels such as low volatile coal, carbon, and boron have low laminar flame speeds (of the order of several centimeters per second). Gravitational convection that occurs in combustion products due to the buoyancy forces disrupts low speed dust flames and, therefore, makes observation of such flames at normal gravity impossible. The only way to carry out 'clean' fundamental experiments in dust combustion over a wide range of dust cloud parameters is in a gravity-free environment. Access to the microgravity environment provided by the use of large-scale drop towers, parabolic flights of aircraft and rockets, and shuttle and space station orbits has permitted now to proceed with a systematic program of dust combustion microgravity research. For example, the NASA-Lewis drop tower and a Lear jet parabolic flight aircraft were used by Ross et al. and by Berlad and Tangirala for experiments with Iycopodium/air mixtures. The Japan Microgravity Center drop shaft (JAMIC) where a microgravity condition of 10(exp -4) g for 10 s is available, was recently used by Kobayashi, Niioka et al. for measuring flame propagation velocities in polymethyl methacrylate dust/air suspensions. Microgravity dust combustion experiments were started at McGill University in the early 90's under the sponsorship of the Canadian Space Agency. Several generations of dust combustion platforms permitting dust combustion microgravity experiments to be carried out on board a parabolic flight aircraft (KC-135, NASA) have been designed and tested. The experimental data and experience gained from this research allowed us to design and build in a current phase of this program the microgravity apparatus for the visual observation of freely propagating constant pressure laminar dust flames. Quenching distances in aluminum dust suspensions have been measured in a wide range of dust cloud parameters in ground-based experiments and in recent microgravity experiments (KC-135 parabolic flights, Houston, February 1995).

Goroshin, S.↗
NASA NTRS1991

Station keeping strategy for multiple spacecraft interferometry

The feasibility of multiple spacecraft stationkeeping for submillimeter and optical interferometry is examined. A condition for interferometry is that two or more spacecraft must control their relative positions with better than 1 mn accuracy indefinitely in both radial and transverse directions although separated by as much as 1 Km in LEO and 100 Km in GEO. They must also maneuver through a useful area of the U-V plane of an arbitrary astronomical source. The problem is first outlined and a solution which utilizes gravity gradient forces to do most of the work and ion thrusters for additional maneuvering is proposed. All the perturbing forces are shown to be small compared to the ion thruster requirements. An inertial position and attitude control strategy is suggested which utilizes existing or soon to be available sensors and actuators. Finally, the fuel and power system mass requirements are estimated and found to be within reason for a 10 year mission.

Decou, Anthony B.↗
DOE OSTI2026

A comparison of wrought and powder metallurgical FeCrAl claddings under simulated LWR accident transients

Iron-chromium-aluminum (FeCrAl) alloys are potential accident tolerant fuel (ATF) cladding candidates for light-water reactors but are difficult to fabricate as thin-walled tubes via conventional cast-and-wrought routes. Powder metallurgy (PM) offers a manufacturing alternative with improved compositional control, but its transient accident performance has not been directly benchmarked against wrought variants. This study evaluates the burst behavior of commercially developed PM-processed FeCrAl alloys, PM-C26M (Fe-12Cr-6Al-2Mo) and the high precipitate density FA-SMT (Fe-22Cr-5Al-3Mo), under simulated light-water reactor accident transient conditions. Burst testing was conducted using the Severe Accident Test Station with heating rates of 5 °C/s and 50 °C/s and internal pressures ranging from 25 MPa to 100 MPa. PM-C26M reproduced wrought C26M burst behavior within 7–37 °C across the stress range, indicating that PM processing does not compromise transient strength. FA-SMT exhibited markedly higher burst temperatures and reduced heating-rate sensitivity, consistent with its engineered precipitate strengthening. FA-SMT rupture exhibited axial "unzipping" rather than the lateral tearing characteristic of PM- and wrought C26M. Post-test EBSD and fractography indicate that this behavior is strongly correlated with strain-gated intergranular void nucleation associated with the dense precipitate architecture of FA-SMT, a response absent in the comparatively clean PM-C26M matrix and consistent with rupture morphologies reported for oxide-dispersion strengthened (ODS) FeCrAl of similar base-matrix chemistry to PM-C26M. These findings highlight the potential of powder metallurgy as a viable fabrication route for ATF claddings from an accident performance standpoint.

Bell, Sam [ORNL] (ORCID:0000000251905657)↗
NASA NTRS2005

High-Altitude, Long-Endurance Airships for Coastal Surveillance

A high altitude solar powered airship provides the ability to carry large payloads to high altitudes and remain on station for extended periods of time. This study examines applications and background of this type of concept vehicle, reviews the history of high altitude flight and provides a point design analysis. The capabilities and limitations of the airship are demonstrated and possible solutions are proposed. Factors such as time of year, latitude, wind speeds, and payload are considered in establishing the capabilities of the airship. East and west coast operation is evaluated. The key aspect to success of this type of airship is the design and operation of the propulsion and power system. A preliminary propulsion/power system design was produced based on a regenerative fuel cell energy storage system and solar photovoltaic array for energy production. Results on power system requirements for year long operation is presented.

Dolce, James L.↗
NASA NTRS2010

International Space Station USOS Potable Water Dispenser On-Orbit Functionality Versus Design

The International Space Station (ISS) currently provides potable water dispensing for rehydrating crewmember food and drinking packages. There is one system located in the United States On-orbit Segment (USOS) and one system in the Russian Segment. Shuttle mission STS-126 delivered the USOS Potable Water Dispenser (PWD) to ISS on ULF2; subsequent activation occurred on November 2008. The PWD is capable of supporting an ISS crew of six, but nominally supplies only half this crew size. The PWD design provides incremental quantities of hot and ambient temperature potable water to US food and beverage packages. PWD receives iodinated water from the US Water Recovery System (WRS) Fuel Cell Water Bus, which feeds from the Water Processing Assembly (WPA). The PWD removes the biocidal iodine to make the water potable prior to dispensing. A heater assembly contained within the unit supplies up to 2.0 L of hot water (65 to 93 ?C) every 30 min. During a single meal, this quantity of water supports three to four crewmembers? food rehydration and beverages. The unit design has a functional life expectancy of 10 years, with replacement of limited life items, such as filters. To date, the PWD on-orbit performance is acceptable. Since activation of the PWD, there were several differences between on-orbit functionality and expected performance of hardware design. The comparison of on-orbit functionality to performance of hardware design is discussed for the following key areas: 1) microbial contamination, 2) no-dispense and water leakage scenarios, and 3) under-dispense scenarios.

Toon, Katherine P.↗