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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 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
NASA NTRS2010

Thermal Performance of Orion Active Thermal Control System With Seven-Panel Reduced-Curvature Radiator

The active thermal control system (ATCS) of the crew exploration vehicle (Orion) uses radiator panels with fluid loops as the primary system to reject heat from spacecraft. The Lockheed Martin (LM) baseline Orion ATCS uses eight-panel radiator coated with silver Teflon coating (STC) for International Space Station (ISS) missions, and uses seven-panel radiator coated with AZ 93 white paint for lunar missions. As an option to increase the radiator area with minimal impact on other component locations and interfaces, the reduced-curvature (RC) radiator concept was introduced and investigated here for the thermal perspective. Each RC radiator panel has 15 percent more area than each Lockheed Martin (LM) baseline radiator panel. The objective was to determine if the RC seven-panel radiator concept could be used in the ATCS for both ISS and lunar missions. Three radiator configurations the LM baseline, an RC seven-panel radiator with STC, and an RC seven-panel radiator with AZ 93 coating were considered in the ATCS for ISS missions. Two radiator configurations the LM baseline and an RC seven-panel radiator with AZ 93 coating were considered in the ATCS for lunar missions. A Simulink/MATLAB model of the ATCS was used to compute the ATCS performance. Some major hot phases on the thermal timeline were selected because of concern about the large amount of water sublimated for thermal topping. It was concluded that an ATCS with an RC seven-panel radiator could be used for both ISS and lunar missions, but with two different coatings STC for ISS missions and AZ 93 for lunar missions to provide performance similar to or better than that of the LM baseline ATCS.

Wang, Xiao-Yen J.↗
NASA NTRS2017

Mars Phoenix Scout Thermal Evolved Gas Analyzer (TEGA) Database: Thermal Database Development and Analysis

The Mars Phoenix Scout Lander mission in 2008 examined the history of water, searched for organics, and evaluated the potential for past/present microbial habitability in a martian arctic ice-rich soil [1]. The Thermal Evolved Gas Analyzer (TEGA) instrument measured the isotopic composition of atmospheric CO2 and detected volatile bearing mineralogy (perchlorate, carbonate, hydrated mineral phases) in the martian soil [2-7]. The TEGA data are archived at the Planetary Data System (PDS) Geosciences Node but are reported in forms that require further processing to be of use to the non-TEGA expert. The soil and blank TEGA thermal data are reported as duty cycle and must be converted to differential power (mW) to allow for enthalpy calculations of exothermic/endothermic transitions. The exothermic/endothermic temperatures are also used to determine what phases (inorganic/organic) are present in the sample. The objectives of this work are to: 1) Describe how interpretable thermal data can be created from TEGA data sets on the PDS and 2) Provide additional thermal data interpretation of two Phoenix soils (Baby Bear, Wicked Witch) and include interpretations from three unreported soils (Rosy Red 1, 2, and Burning Coals).

Sutter, B.↗
NASA NTRS2018

Temperature-Staged Thermal Energy Storage Enabling Low Thermal Exergy Loss Reflux Boiling in Full Spectrum Solar Energy Systems

The efficiency of solar power collection is increased by adding a thermal energy storage stage to a sunlight concentrator and thermodynamic power generator system. The thermal energy storage includes tubes or capsules made of a phase change material that stores thermal energy in different temperature stages through a working fluid. The stored thermal energy is directed to the thermodynamic generator during off-sun periods.

Hendricks, Terry↗
NASA NTRS2014

Fundamental Property Requirements for Thermal and Mechanical Response Analysis of Thermal Protection Materials and Systems

Spacecraft that are designed to reenter the Earth's atmosphere, or enter the atmosphere of another planet, require Thermal Protection Systems (TPS) in order to survive the extreme thermal environments during the atmospheric flight. Analytical modeling of thermal and mechanical response is a fundamental aspect of the design of TPS and development of TPS materials. The analyses are used to understand the response of the materials and systems under representative environments. Performing these analyses, and evaluating the results, requires a variety of fundamental inputs, including: thermal and mechanical material properties; predicted or measured ground test and flight environments; and information about adjacent structure or attachments. We explain the nature of the analyses, highlight the essential fundamental data that are required, and describe the impact of the accuracy in the input data on the final results. We also describe the important priorities in material characterization testing in support of analyses.

Squire, Thomas↗
NASA NTRS2020

Passive Thermal Coating Observatory Operating in Low-Earth Orbit (PATCOOL) – Cubesat Design to Test Passive Thermal Coatings in Space

The PATCOOL is a NASA sponsored, University of Florida developed 3U Cu-beSat meant to investigate the feasibility of using a cryogenic selective surface coating as a new, more efficient way of passively cooling components in space. Initial tests on the ground demonstrate that this coating should provide a much higher reflectance of the Sun’s irradiant power than any existing coating, while still providing far-infrared power emission. The ultimate validation of this tech-nology requires on-orbit testing. PATCOOL hosts a 4-sample housing, with the samples shaped as thin cylinders (coin-like). Two samples are coated with state-of-the-art material, while the other pair uses the new coating to be evaluated. The temperatures of all samples during the mission (minimum 72 hours of data col-lection) are measured via thermistors. The samples are connected via thin Kevlar strings to the housing, to minimize heat transfer. The housing is designed to shield the samples from Earth’s thermal radiation, and the CubeSat is attitude stabilized and controlled via a gravity gradient boom, magnetorquers and a reaction wheel set. Thermal Desktop simulations show PATCOOL’s ability to thermally isolate the samples from heat exchanges other than with Sun and deep space, thanks to its thermal design and the chosen attitude profile.

Ojeda, Carlos↗
NASA NTRSDate not supplied

Integrated Computational Fluid Dynamics and Thermal Desktop Thermal Modeling for Assessment of the EMU in Support of ISS EVA 80

Following the reports of water accumulation in the Extravehicular Mobility Unit (EMU) helmet during the ISS US EVA-80, various efforts for mitigation and further understanding of this phenomenon have been undertaken with the goal of prevention and to ensure crew safety in future EVAs. In support of this goal, a combination of Thermal Desktop thermal modeling and Computational Fluid Dynamics (CFD) has been performed in order to characterize the performance of the EMU components, specifically those within the ventilation/cooling water loops. This modeling effort evaluates the dry/wet gas pressure drop and flow distribution through gas and liquid flow paths using CFD, as well as a two-phase flow assessment of condensation production and water separation/removal performance using an integrated Thermal Desktop model of important EMU ventilation loop components. The models assess this overall thermal-fluid performance in comparison with previous existing models, design points, and historical EVA data using their inputs.

Blain Ryan Lancaster↗
NASA NTRS2022

Thermal Design of the Thermal Infrared Spectrometer (TIRS) Instrument on PREFIRE

The Polar Radiant Energy in the Far-Infrared Experiment (PREFIRE) consists of two 6U CubeSats that each host a Thermal Infrared Spectrometer (TIRS) instrument. The CubeSats are scheduled for launch in March and October of 2023. The purpose of the TIRS instrument is to make spectrally resolved measurements of the Earth’s thermal radiation from the top of the atmosphere. PREFIRE will document, for the first time, variability in spectral fluxes from 4 to 54 microns on hourly to seasonal timescales. The primary mission is 12 months in a polar orbit with inclination of 82 to 98 at altitudes between 450 km and 650 km. The TIRS instrument is an Offner spectrometer that uses a thermopile detector array and a Schwarzchild telescope. In addition, there is a scan mirror which is periodically actuated for calibration. The instrument concept of operation is to collect radiation emitted towards zenith in a nadir sounding orientation with periodic internal and space calibrations. The TIRS thermal control architecture consists of entirely passive elements. The instrument requires all elements be maintained between 0 C and 50 C during operation for the duration of the mission. An overview of the overall thermal control design approach is presented.

Andrade, Andres↗
NASA NTRSDate not supplied

Integrated Computational Fluid Dynamics and Thermal Desktop Thermal Modeling for Assessment of the EMU in Support of ISS EVA 80

Following the reports of water accumulation in the Extravehicular Mobility Unit (EMU) helmet during the ISS US EVA-80, various efforts for mitigation and further understanding of this phenomenon have been undertaken with the goal of prevention and to ensure crew safety in future EVAs. In support of this goal, a combination of Thermal Desktop thermal modeling and Computational Fluid Dynamics (CFD) has been performed in order to characterize the performance of the EMU components, specifically those within the ventilation/cooling water loops. This modeling effort evaluates the dry/wet gas pressure drop and flow distribution through gas and liquid flow paths using CFD, as well as a two-phase flow assessment of condensation production and water separation/removal performance using an integrated Thermal Desktop model of important EMU ventilation loop components. The models assess this overall thermal-fluid performance in comparison with previous existing models, design points, and historical EVA data using their inputs.

EVA 80↗
DOE OSTI2011

Bentonite alteration due to thermal-hydro-chemical processes during the early thermal period in a nuclear waste repository

After closure of an underground nuclear waste repository, the decay of radionuclides will raise temperature in the repository, and the bentonite buffer will resaturate by water inflow from the surrounding host rock. The perturbations from these thermal and hydrological processes are expected to dissipate within hundreds to a few thousand years. Here, we investigate coupled thermal-hydro-chemical processes and their effects on the short-term performance of a potential nuclear waste repository located in a clay formation. Using a simplified geometric configuration and abstracted hydraulic parameters of the clayey formation, we examine geochemical processes, coupled with thermo-hydrologic phenomena, and potential changes in porosity near the waste container during the early thermal period. The developed models were used for evaluating the mineral alterations and potential changes in porosity of the buffer, which can affect the repository performance. The results indicate that mineral alteration and associated changes in porosity induced by early thermal and hydrological processes are relatively small and are expected to not significantly affect flow and transport properties. Chlorite precipitation was obtained in all simulation cases. A maximum of one percent volume fraction of chlorite could be formed, whose process may reduce swelling and sorption capacity of bentonite clay, affecting the performance of the repository. llitisation process was not obtained from the present simulations.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Method and apparatus for implementing material thermal property measurement by flash thermal imaging

A method and apparatus are provided for implementing measurement of material thermal properties including measurement of thermal effusivity of a coating and/or film or a bulk material of uniform property. The test apparatus includes an infrared camera, a data acquisition and processing computer coupled to the infrared camera for acquiring and processing thermal image data, a flash lamp providing an input of heat onto the surface of a two-layer sample with an enhanced optical filter covering the flash lamp attenuating an entire infrared wavelength range with a series of thermal images is taken of the surface of the two-layer sample.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Ternary ceramic thermal spraying powder and method of manufacturing thermal sprayed coating using said powder

The invention describes a method for producing ternary and binary ceramic powders and their thermal spraying capable of manufacturing thermal sprayed coatings with superior properties. Powder contain at least 30% by weight ternary ceramic, at least 20% by weight binary molybdenum borides, at least one of the binary borides of Cr, Fe, Ni, W and Co and a maximum of 10% by weight of nano and submicro-sized boron nitride. The primary crystal phase of the manufactured thermal sprayed coatings from these powders is a ternary ceramic, while the secondary phases are binary ceramics. The coatings have extremely high resistance against corrosion of molten metal, extremely thermal shock resistance and superior tribological properties at low and at high temperatures.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Ternary ceramic thermal spraying powder and method of manufacturing thermal sprayed coating using said powder

The invention describes a method for producing ternary and binary ceramic powders and their thermal spraying capable of manufacturing thermal sprayed coatings with superior properties. Powder contain at least 30% by weight ternary ceramic, at least 20% by weight binary molybdenum borides, at least one of the binary borides of Cr, Fe, Ni, W and Co and a maximum of 10% by weight of nano and submicro-sized boron nitride. The primary crystal phase of the manufactured thermal sprayed coatings from these powders is a ternary ceramic, while the secondary phases are binary ceramics. The coatings have extremely high resistance against corrosion of molten metal, extremely thermal shock resistance and superior tribological properties at low and at high temperatures.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Thermal measurement apparatus and methods for anisotropic thermal materials

A system for characterizing thermal properties of thermally anisotropic heterogeneous samples includes a heating element, a first temperature sensing device, a second temperature sensing device, and a computing system. The heating element is positioned at a first location within a sample and heats the sample. The first temperature sensing device outputs data indicative of temperatures of the first location to the computing device. The second temperature sensing device outputs data indicative of temperatures of the second location to the computing device. The computing device computes a thermal conductivity of the sample based upon the temperatures of the first location. The computing device further outputs an indication of a portion of the sample to which the thermal conductivity pertains based upon the second temperatures.

Reyes, Karla Rosa↗
DOE OSTI2023

Thermal measurement apparatus and methods for anisotropic thermal materials

A system for characterizing thermal properties of thermally anisotropic heterogeneous samples includes a heating element, a first temperature sensing device, a second temperature sensing device, and a computing system. The heating element is positioned at a first location within a sample and heats the sample. The first temperature sensing device outputs data indicative of temperatures of the first location to the computing device. The second temperature sensing device outputs data indicative of temperatures of the second location to the computing device. The computing device computes a thermal conductivity of the sample based upon the temperatures of the first location. The computing device further outputs an indication of a portion of the sample to which the thermal conductivity pertains based upon the second temperatures.

Reyes, Karla Rosa↗
DOE OSTI2025

Initial steady-state core simulation capability or thermal and pool-type molten salt reactors, coupling reactor physics, thermal-hydraulics, and evolving chemistry

This report presents the development and validation of an initial steady-state multiphysics capability for molten salt reactors (MSRs) under the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program in Fiscal Year 2025. The framework integrates neutronics, thermal-hydraulics, species transport, and thermochemistry to capture the coupled dynamics of liquid-fueled systems. Implementation and testing were performed on two representative designs: the Molten Salt Reactor Experiment (MSRE), a thermal-spectrum, channeled-flow reactor, and the Lotus Molten Salt Reactor (L-MSR), a fast-spectrum, pool-type reactor. The modeling suite employs Griffin for reactor physics and depletion, Pronghorn and SAM for thermal-hydraulics, Thermochimica for chemistry, and Saline for thermophysical properties, with benchmarking and validation carried out against historical MSRE data, experimental flow-loop measurements, and reference depletion calculations from Monte Carlo codes. The framework demonstrated the ability to reproduce key reactor behaviors including temperature feedback, reactivity losses, delayed neutron precursor transport, xenon poisoning, and redox potential evolution. The results confirm the feasibility and accuracy of the coupled models in predicting steady-state and selected transient MSR behaviors. This latter ones are used in this report as a proxy indicating that the steady-state models from which the transient starts are accurate. For MSRE, validation showed good agreement with pump start-up and natural circulation tests, while for the L-MSR, benchmarking confirmed hydraulic calibration and consistency of neutronics–thermal coupling. The tools also provided new insights into species transport, noble metal deposition, and salt solidification dynamics. On the Xenon transport front, the code is validated against the steady state Xenon poisoining measurement and showed good agreement with the experimental value. Identified areas for future work include advanced void transport modeling, three-dimensional simulations, improved alloy corrosion models, and tighter integration with high-fidelity Monte Carlo codes. These developments provide a foundation for high-fidelity MSR simulations that can support reactor design optimization, safety assessments, and long-term operational strategies.

42 - ENGINEERING↗
DOE OSTI2020

Non-invasive (non-contact) measurements of human thermal physiology signals and thermal comfort/discomfort poses -A review

Heating, ventilation and air-conditioning (HVAC) systems have been adopted to create comfortable, healthy and safe indoor environments. In the control loop, the technical feature of the human demand-oriented supply can help operate HVAC effectively. Among many technical options, real time monitoring based on feedback signals from end users has been frequently reported as a critical technology to confirm optimizing building performance. Recent studies have incorporated human thermal physiology signals and thermal comfort/discomfort status as real-time feedback signals. A series of human subject experiments used to be conducted by primarily adopting subjective questionnaire surveys in a lab-setting study, which is limited in the application for reality. With the help of advanced technologies, physiological signals have been detected, measured and processed by using multiple technical formats, such as wearable sensors. Nevertheless, they mostly require physical contacts with the skin surface in spite of the small physical dimension and compatibility with other wearable accessories, such as goggles, and intelligent bracelets. Most recently, a low cost small infrared camera has been adopted for monitoring human facial images, which could detect the facial skin temperature and blood perfusion in a contactless way. Also, according to latest pilot studies, a conventional digital camera can generate infrared images with the help of new methods, such as the Euler video magnification technology. Human thermal comfort/discomfort poses can also be detected by video methods without contacting human bodies and be analyzed by the skeleton keypoints model. Here, new sensing technologies were summarized, their cons and pros were discussed, and extended applications for the demand-oriented ventilation were also reviewed as potential development and applications.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2024

Coupling thermal energy storage with a thermally anisotropic building envelope for building demand-side management across various US climate conditions

Here, the thermally anisotropic building envelope (TABE) is a novel active building envelope that enhances energy efficiency and thermal comfort in buildings by transferring heat and cold between building envelopes and hydronic loops. When coupled with thermal energy storage (TES) units, the TABE + TES enables the storage of both heat and cold energy captured by the TABE roof or exterior walls. This stored energy can be later released by the TABE floor for indoor heating and cooling, benefiting both the grid and the end user. This paper evaluates the merits of TABE + TES for building demand-side management across various US climate conditions, focusing on peak load shaving, annual energy savings, and cost savings under time-of-use (TOU) electric rate schedules. Simulations were conducted by integrating time-of-day–informed, rule-based control strategies in MATLAB, TABE components and TES units in COMSOL Multiphysics, and whole-building energy analysis in EnergyPlus. A case study using the US Department of Energy’s prototype single-family detached house model in Birmingham, Alabama; Los Angeles, California; Oak Ridge, Tennessee; and Denver, Colorado, showed that the TABE + TES system achieved (1) 70 % peak load shaving in Los Angeles and Denver and 20 % in Birmingham and Oak Ridge; (2) significant peak electricity savings of 351–497 kWh, reducing peak energy consumption by 38 %–78 %; and (3) annual heating cost savings of 0.79 $\$$/m2–1.17 $\$$/m 2 and cooling cost savings of 0.60 $\$$/m 2 –1.17 $\$$/m 2 using a normal utility rate or low-TOU rate. The benefits of employing the TABE + TES system are even more significant under high TOU rates.

25 ENERGY STORAGE↗
DOE OSTI2013

Step-by-step thermal transformations of a new porous coordination polymer [(H{sub 2}O){sub 5}CuBa(Me{sub 2}mal){sub 2}]{sub n} (Me{sub 2}mal{sup 2-}=dimethylmalonate): Thermal degradation to barium cuprate

The reactions of CuSO{sub 4}{center_dot}5H{sub 2}O, dimethylmalonic acid and Ba(OH){sub 2}{center_dot}H{sub 2}O (Cu: H{sub 2}Me{sub 2}mal: Ba=1: 2: 2) in aqueous and aqueous-ethanol solutions (H{sub 2}O: EtOH=1: 1) resulted in formation of 3D-porous coordination polymers [(H{sub 2}O){sub 3}({mu}-H{sub 2}O){sub 2}CuBa({mu}{sub 3}-Me{sub 2}mal)(Me{sub 2}mal)]{sub n} (1) and [({mu}-H{sub 2}O)CuBa({mu}{sub 3}-Me{sub 2}mal)({mu}{sub 4}-Me{sub 2}mal)]{sub n} (2), respectively. It has been shown that compound 2 was an intermediate in the thermal degradation of compound 1. Thorough studies of solid-state thermolysis of 1 and 2 allowed to detect formation of coordination polymer [CuBa({mu}{sub 4}-Me{sub 2}mal)({mu}{sub 5}-Me{sub 2}mal)]{sub n} (3), structure of which was determined by X-ray powder diffraction. It has been found that the channels in polymer 3 were accessible for guest molecules (MeOH). Theoretical estimation of methanol diffusion barrier was carried out. Complete solid-phase thermolysis of 1 and 2 leads to a mixture of BaCuO{sub 2}, BaCO{sub 3}, and CuO. Special conditions for obtaining of a crystalline phase of pure cubic BaCuO{sub 2} were determined. - Graphical abstract: Step-by-step transformation of new coordination polymer [(H{sub 2}O){sub 5}CuBa(Me{sub 2}mal){sub 2}]{sub n} to [(H{sub 2}O)CuBa(Me{sub 2}mal){sub 2}]{sub n} and [CuBa(Me{sub 2}mal){sub 2}]{sub n} were performed. Dehydration of initial compound leads to structural changes of 12-membered ring fragment. All compounds have porous structure. The final product of thermal decomposition is crystalline phase of individual cubic BaCuO{sub 2}. Highlights: Black-Right-Pointing-Pointer New 3D-polymers [(H{sub 2}O){sub 5}CuBa(Me{sub 2}mal){sub 2}]{sub n} and [(H{sub 2}O)CuBa(Me{sub 2}mal){sub 2}]{sub n} were synthesized. Black-Right-Pointing-Pointer Thermal analysis showed step-by-step transformations of [(H{sub 2}O){sub 5}CuBa(Me{sub 2}mal){sub 2}]{sub n}. Black-Right-Pointing-Pointer Crystalline phase of pure cubic BaCuO{sub 2} is the product solid-phase thermolysis.

36 MATERIALS SCIENCE↗