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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS2016

MLI Blanket Effective Emittance Variance and Its Effect on Spacecraft Propellant Line Thermal Control

Multi-Layer Insulation (MLI) blankets commonly employed for temperature control of spacecraft propellant lines consistently show large variances in their effective emittances. These variances are primarily due to workmanship, hence are hard to control or predict. Unfortunately, the variances are also the primary drivers of propellant line temperatures, thus leading to large predicted temperature uncertainties and increased risks to the success of space missions. JPL has gained significant knowledge of these variances from Mars spacecraft designs over more than two decades. This knowledge has led to improved analytical approaches to bound existing designs, emphasis on increased temperature visibility for design verification and model correlation, as well as methods for improving the robustness of propellant line thermal designs.

Miller, Jennifer R.↗
NASA NTRS2019

Loftid Aeroshell Engineering Development Unit Structural Testing

NASA’s Hypersonic Inflatable Aerodynamic Decelerator (HIAD) technology was selected for a Technology Demonstration Mission under the Space Technology Mission Directorate in 2017. HIAD is an enabling technology that can facilitate atmospheric entry of heavy payloads to planets such as Earth and Mars using a deployable aeroshell. The deployable nature of the HIAD technology allows it to avoid the size constraints imposed on current rigid aeroshell entry systems. This enables use of larger aeroshells resulting in increased entry system performance (e.g. higher pay-load mass and/or volume, higher landing altitude at Mars). The Low Earth Orbit Flight Test of an Inflatable Decelerator (LOFTID) is currently scheduled for late-2021. LOFTID will be launched out of Vandenberg Air Force Base as a secondary payload on an Atlas V rocket. The flight test features a 6m diameter, 70-deg sphere-cone aeroshell and will provide invaluable high-energy orbital re-entry flight data. This data will be essential in supporting the HIAD team to mature the technology to diameters of 10m and greater. Aeroshells of this scale are applicable to potential near-term commercial applications and future NASA missions. Currently the LOFTID project has completed fabrication of the engineering design unit (EDU) inflatable structure (IS) and the flexible thermal protection system (F-TPS). These two components along with the rigid nose and center body comprise the HIAD aeroshell system. This EDU aeroshell is the precursor to the LOFTID aeroshell that will be used for flight. The EDU was built to verify the design given the subtle differences between the LOFTID aeroshell and past aeroshell designs that have been fabricated under the NASA HIAD project. To characterize the structural performance of the LOFTID aeroshell design, three structural tests will be performed. The first test to be conducted is static load testing, which will induce a uniform load across the forward surface of the aeroshell to simulate the expected pressure forces during atmospheric entry. The IS integrated with the rigid center body will first be tested alone to provide data for analytical model correlation, and then the F-TPS will be integrated for a second series of static load testing of the full aeroshell system. Instrumentation will be employed during the test series to measure component loads during testing, and a laser scanner will be used to generate a 3D map of the aeroshell surface to verify that the shape of the structure is acceptable at the simulated flight loads. After static load testing, pack and deployment testing will be conducted multiple times on the integrated system to demonstrate the aeroshell’s ability to fit within the required packed volume for the LOFTID mission without experiencing significant damage. Finally, the aeroshell will undergo modal testing to characterize its structural response. This presentation will discuss the setup and execution of each of the three tests that the EDU aeroshell will undergo. In addition, initial results of the testing will be presented outlining key findings as LOFTID moves for-ward with fabrication of the flight aeroshell.

Swanson, G. T.↗
NASA NTRS2016

Magnetic Shield Design Modeling and Validation for SWOT Spacecraft Ka-Band Extended Interaction Klystron

Two Extended Interaction Klystrons (EIKs) containing strong permanent magnets were modeled magnetically in a representative spacecraft geometry using commercial finite element modeling techniques and were validated against measurements made at varying distances. Initial modeling results for the 63 A-m2 dipole moment magnets showed that magnetic shields would be necessary in order to meet magnetic field requirements for the Surface Water and Ocean Topography (SWOT) spacecraft, which contains components that are susceptible to external DC magnetic fields. JPL and the EIK vendor proposed cold rolled steel and mu-metal as potential shield materials along with proposed thicknesses of 0.5 mm and 1.5 mm. Magnetic shields made from each of these materials were designed and modeled in software, taking highfield saturation into account. Prototype magnetic shields with these parameters were then built, measured with an existing EIK, and compared against modeling results. For single-axis field measurements along the dipole axis, modeling results were within 7 gauss of the measured values at 10 cm from the magnet, and converged to less than 1.5 gauss at distances greater than 14 cm from the magnet. Three-axis field measurements at locations of interest showed that model correlation improved to within 4 gauss at 11 cm and 2 gauss for distances ranging between 15 cm and 36 cm.

Gonzales, Edward↗
NASA NTRS2019

Thermal design and validation of Mars 202 gas Dust Removal Tool (gDRT)

As part of the science goals for the planned Mars 2020 mission, two instruments, PIXL and SHERLOC, intend to study the Mars surface at a close scale. These two instruments are planned to be used on smooth rock surfaces that are free of dust and other particles. Such surfaces are prepared by using a drill with an abrading drill bit; residual dust and particles are then blown away using a compressed gas system—the Gas Dust Removal Tool (gDRT). Early in the design process a risk of valve leakage below the vendor’s -20C rating was identified. To mitigate this risk a parallel path was implemented: 1) qualify the valves to operate at -135C, and 2) develop thermal control capability to elevated temperatures in case qualification efforts are unsuccessful. While qualification efforts are ongoing, it is expected that the valves will be qualified to an operating temperature of -135C. In the event that qualification is not successful, thermal control has been realized via a thermally isolated valve configuration and thermostatically controlled heaters. Thermal testing of gDRT has validated this design and enabled thermal model correlation in order to provide more accurate survival energy predictions. The resulting energy consumption for heating the valves at the Jezero landing site represents a minimal impact to the Rover energy budget.

Novak, Keith↗
NASA NTRS2019

Thermal testing of a Mars 2020 enhanced engineering camera

The upcoming Mars 2020 rover mission is introducing a new generation of engineering cameras (ECAMs) called the enhanced engineering cameras (EECAMs), which have advanced imaging capability over the previous ECAMs used on the Spirit, Opportunity, and Curiosity rovers. The Mars 2020 rover will have nine EECAMs – six upgraded HazCams used for hazard avoidance, two upgraded NavCams used for navigation, and a single CacheCam used to take images of samples obtained by the rover’s Sampling and Caching Subsystem (SCS). The detailed EECAM design was completed in April 2017, and since then the EECAM Subsystem has been in the process of fabrication, integration, and testing. This paper describes two thermal tests that were done for thermal model correlation and validation of the EECAM thermal design during Mars surface operations.

Novak, Keith S.↗
NASA NTRS2020

Thermal system and environmental testing of the Mars Helicopter

The Mars Helicopter will be a technology demonstration conducted during the Mars 2020 mission. The primary mission objective is to achieve several 90-second flights demonstrating the feasibility of heavier than air flight on Mars and capture visible light images via forward and nadir mounted cameras. These flights could possibly provide reconnaissance data for sampling site selection for other Mars surface missions. A solar array and batteries for flight operations, imaging, communications, and survival heating power the Helicopter. The thermal design is driven by minimizing survival heater energy while maintaining compliance with allowable flight temperatures in a variable thermal environment. Due to the small size of the Helicopter and its complex geometries, along with the fact that it operates with very low power and small margins in the extreme Mars environment, additional care had to be paid while planning thermal tests and designing the thermal system. The first section of the paper describes the evolution of the thermal system of the Mars Helicopter. After the first thermal vacuum test of the engineering model, the thermal team has conducted a partial effect analysis on the thermal design components that had a major impact on the system performance. Several design choices derived by analysis and test have been made to meet the energy allocation and the temperature requirements. These changes included increased gas gaps to reduce gas conduction, low emissivity coatings for internal components, blanket implementation, optimization of wire routing and fine-tuning of surface operations to optimize waste heat recovery. The second part of the paper describes the flight model thermal vacuum test and the subsequent thermal model correlation necessary to confirm the fidelity of the analysis results.

Pauken, Michael↗
NASA NTRSDate not supplied

How History can inform an Analysis of Alternatives Study

Pathways to Discovery in Astronomy and Astrophysics for the 2020s has recommended a Great Observatory Maturation Program (GOMaP) to invest in co-maturation of mission concepts and technologies to inform an Analysis of Alternatives (AOA) study for an approximate 6-meter off-axis inscribed telescope to sample atmospheric spectra of ~25 potentially habitable exoplanets using UV, visible and Nir-IR wavelengths and to be launched in the early 2040s with a total cost of less than $11B including 5 years of operation. The history of past missions indicates that technology development is critical for enabling missions, the robustness, breadth, and duration of concept/technology co-maturation is important for mission success. NASA has not ‘exactly’ implemented Decadal missions as recommended. And, all missions have the same basic technology challenges of mass constraints, mechanical and thermal stability to design and build a space telescope that achieves the required on-orbit performance – and how to verify and validate that performance by test and model correlation.

space telescopes↗
NASA NTRSDate not supplied

Analysis of Hot-Wire Probe Ice Water Content Measurements in High Ice Water Content Conditions

During the 2022 High Ice Water Content (HIWC) Flight Campaign, ice water content (IWC) measurements were made at various locations on the NASA DC-8 Airborne Science Laboratory using the Isokinetic Probe Version 2 (IKP2), Ice Crystal Detectors (ICD), and Robust Probe. Correlations of a wing mounted ICD to IKP2 were made to determine the collision/retention efficiency of the ICD total water content (TWC) element in glaciated conditions. Similarly, correlations of a nose mounted ICD near the pitot probes were made to the IKP2 and to the wing-mounted ICD to estimate the ice concentration factor near the DC-8 pitot probes. Results from the 2022 flight campaign were compared to results from the HIWC RADAR II flight campaign in 2018. There was an apparent reduction in the ICD TWC collision/retention efficiency during the 2022 flight campaign. Although reasons for this discrepancy were explored, more analyses are needed to fully understand the causes. However, it was concluded that an estimated ice concentration factor at the nose of 2.5 was consistent between the two flight campaigns. Additionally, a correlation model was developed to relate measurements from a Nose ICD to freestream IWC as measured by the IKP2 to support IWC measurements from the 2022 Convective Processes Experiment - Cabo Verde (CPEX-CV) flight campaign.

Icing↗
NASA NTRSDate not supplied

Analysis of Hot-Wire Probe Ice Water Content Measurements in High Ice Water Content Conditions

During the 2022 High Ice Water Content (HIWC) Flight Campaign, ice water content (IWC) measurements were made at various locations on the NASA DC-8 Airborne Science Laboratory using the Isokinetic Probe Version 2 (IKP2), Ice Crystal Detectors (ICD), and Robust Probe. Correlations of a wing mounted ICD to IKP2 were made to determine the collision/retention efficiency of the ICD total water content (TWC) element in glaciated conditions. Similarly, correlations of a nose mounted ICD near the pitot probes were made to the IKP2 and to the wing-mounted ICD to estimate the ice concentration factor near the DC-8 pitot probes. Results from the 2022 flight campaign were compared to results from the HIWC RADAR II flight campaign in 2018. There was an apparent reduction in the ICD TWC collision/retention efficiency during the 2022 flight campaign. Although reasons for this discrepancy were explored, more analyses are needed to fully understand the causes. However, it was concluded that an estimated ice concentration factor at the nose of 2.5 was consistent between the two flight campaigns. Additionally, a correlation model was developed to relate measurements from a Nose ICD to freestream IWC as measured by the IKP2 to support IWC measurements from the 2022 Convective Processes Experiment - Cabo Verde (CPEX-CV) flight campaign.

Icing↗
NASA NTRSDate not supplied

Harness Thermal Heat Loss Measurement for a Lunar Surface-Deployed LEMS Artemis III Payload

The Lunar Environment Monitoring Station (LEMS) is an autonomous, survive-the-lunar-night seismic suite to be deployed on the Lunar surface by the Artemis III crew and designed to operate continuously for two years. It will see the extremes of the Lunar south pole thermal environment where surface temperatures range from -200°C to +20°C and where nighttime duration is at least 354 hours. Given power and mass constraints, the thermal system is limited to 2.5 Watts of heat during the lunar night. The electrical harnessing named the Signal and Power Passthrough (SAPP) was designed to minimize heat loss while meeting power and signal integrity requirements. To mitigate risk due to uncertainty associated with the harnessing materials, routing, and tie-downs, a flight-like thermal conductance test was performed to measure the heat loss. The test methodology, results, and model correlation are presented.

TVAC↗
NASA NTRSDate not supplied

Harness Thermal Heat Loss Measurement for A Lunar Surface-Deployed LEMS Artemis III Payload

The Lunar Environment Monitoring Station (LEMS) is an autonomous, survive-the-lunar-night seismic suite to be deployed on the Lunar surface by the Artemis III crew and designed to operate continuously for two years. It will see the extremes of the Lunar south pole thermal environment where surface temperatures range from -200°C to +20°C and where nighttime duration is at least 354 hours. Given power and mass constraints, the thermal system is limited to 2.5 Watts of heat during the lunar night. The electrical harnessing named the Signal and Power Passthrough (SAPP) was designed to minimize heat loss while meeting power and signal integrity requirements. To mitigate risk due to uncertainty associated with the harnessing materials, routing, and tie-downs, a flight-like thermal conductance test was performed to measure the heat loss. The test methodology, results, and model correlation are presented.

Thermal↗
NASA NTRSDate not supplied

Harness Thermal Heat Loss Measurement for A Lunar Surface-Deployed LEMS Artemis III Payload

The Lunar Environment Monitoring Station (LEMS) is an autonomous, survive-the-lunar-night seismic suite to be deployed on the Lunar surface by the Artemis III crew and designed to operate continuously for two years. It will see the extremes of the Lunar south pole thermal environment where surface temperatures range from -200°C to +20°C and where nighttime duration is at least 354 hours. Given power and mass constraints, the thermal system is limited to 2.5 Watts of heat during the lunar night. The electrical harnessing named the Signal and Power Passthrough (SAPP) was designed to minimize heat loss while meeting power and signal integrity requirements. To mitigate risk due to uncertainty associated with the harnessing materials, routing, and tie-downs, a flight-like thermal conductance test was performed to measure the heat loss. The test methodology, results, and model correlation are presented.

TVAC↗
NASA NTRS2026

Development and Validation of a High-Vacuum Thermal Conductivity Testbed for Aerospace Interface Materials

Thermal Interface Materials (TIMs) are critical components in spacecraft thermal management systems, where thermal performance is strongly influenced by vacuum conditions, interface contact resistance, and layered metallic joint behavior. However, manufacturer-reported thermal conductivity values are often derived under idealized conditions and may not accurately represent performance within operational aerospace applications. To address this limitation, the Testbed for Advanced Interface Materials in Vacuum (TAIMV) was developed as a modular vacuum-compatible thermal conductivity characterization platform capable of evaluating aerospace-relevant TIM configurations under both ambient and high-vacuum environments. The testbed was derived from the ASTM C1044-16 guarded hot plate methodology and incorporates interchangeable layers of stainless steel coupon geometries, independently controlled main and guard heaters, embedded resistance temperature detectors (RTDs), thermocouples, multi-layer insulation (MLI), and a temperature-controlled cold plate to characterize through-thickness thermal gradients across layered interfaces. In the current configuration, interface compression is limited to the nominal contact pressure generated by the experimental stack assembly. Initial experimental campaigns were conducted at ambient pressure and below 1×10-5 torr for vacuum cases using multiple interface materials including Braycote 601EF and Krytox-based greases across a range of thermal operating conditions. In parallel, a coupled numerical Python thermal model was developed to predict temperature distribution throughout the stack while accounting for conduction, radiation, and parasitic heat transfer pathways and effective interface resistance effects. Experimental measurements and numerical predictions showed consistent thermal trends across multiple operating conditions and environmental states. Results also revealed measurable differences between ambient and vacuum thermal behavior, demonstrating the importance of interface resistance, parasitic heat transfer mechanisms, and stack geometry in determining effective thermal performance within layered thermal interfaces. The presented work establishes a foundation for future thermal model correlation efforts and expanded characterization of aerospace thermal interface materials under representative environmental conditions. Future work will focus on the integration of a load cell system to enable controlled pressure-dependent characterization of thermal interface materials under compressive loading. This capability will allow investigation of the influence of contact pressure on effective thermal conductivity, interface resistance, and thermal performance within layered aerospace thermal interfaces under representative operational conditions.

Thermal Development Testing↗
NASA NTRSDate not supplied

Thermal Design and Thermal Vacuum Testing of the StarBurst Instrument

The StarBurst Multimessenger Pioneer is a small satellite mission serving as a wide-field gamma-ray observatory designed to capture the initial emissions of short gamma-ray bursts, electromagnetic signatures of neutron star mergers. This paper presents the final thermal design and analysis of the StarBurst Instrument, comprising the bus-to-instrument interface plate, control electronics, and twelve crystal detector units, which form the core of the mission’s science capability. The passive thermal control system design requires consideration of restrictive keep-out zones, unknown orbital parameters, and narrow temperature limits of the detectors. Also summarized is the instrument level thermal vacuum cycle test, correlated model refinements, and updated model results. Following successful completion of the instrument test campaign, the hardware was integrated with the spacecraft bus for spacecraft level testing, including additional thermal vacuum testing. The results from the spacecraft level thermal vacuum test will further inform the instrument thermal model, ensuring accurate flight temperature predictions. StarBurst launches as a secondary payload in 2027 and has a mission duration of at least one year.

StarBurst↗
NASA NTRS1984

A correlation of scale model and flight aeroacoustic data for the Space Shuttle vehicle

A correlation is presented between aeroacoustic data acquired in the early Space Shuttle flights and in the various scale model tests from which the Shuttle vibroacoustic design environments were derived. These are the external acoustic data on the vehicle elements at liftoff, during the transonic and maximum dynamic pressure period of ascent flight, and during spent SRB reentry. The maximum external acoustic environment on the Shuttle elements in a given 1/3-octave frequency band comes from one of these critical flight regimes. The data correlation is seen to be good, testifying to adequate scale model measurement and test techniques. Some of the more salient features of the scale model test programs are described.

Dougherty, N. S.↗
DOE OSTI2024

Nanoscale structural correlations in a model cuprate superconductor

Understanding the extent and role of inhomogeneity is a pivotal challenge in the physics of cuprate superconductors. While it is known that structural and electronic inhomogeneity is prevalent in the cuprates, it has proven difficult to disentangle compound-specific features from universally relevant effects. Here, in this study, we combine advanced neutron and x-ray diffuse scattering with numerical modeling to obtain insight into bulk structural correlations in HgBa 2 ⁢ CuO 4+δ . This cuprate exhibits a high optimal transition temperature of nearly 100 K, pristine charge-transport behavior, and a simple average crystal structure without long-range structural instabilities, and is therefore uniquely suited for investigations of intrinsic inhomogeneity. We uncover diffuse reciprocal-space patterns that correspond to prominent nanoscale correlations of atomic displacements perpendicular to the CuO 2 planes. The real-space nature of the correlations is revealed through three-dimensional pair distribution function analysis and complementary numerical refinement. We find that relative displacements of ionic and CuO 2 layers play a crucial role, and that the structural inhomogeneity is not directly caused by the presence of conventional point defects. The observed correlations are therefore intrinsic to HgBa 2 ⁢ CuO 4+δ , and thus likely important for the physics of cuprates more broadly. It is possible that the structural correlations are closely related to the unusual superconducting fluctuations and Mott-localization in these complex oxides. As advances in scattering techniques yield increasingly comprehensive data, the experimental and analysis tools developed here for large volumes of diffuse scattering data can be expected to aid future investigations of a wide range of materials.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2025

Quasielastic lepton-nucleus scattering and the correlated Fermi gas model

The neutrino research program in the coming decades will require improved precision. A major source of uncertainty is the interaction of neutrinos with nuclei that serve as targets for such experiments. Broadly speaking, this interaction often depends, e.g., for charge-current quasielastic scattering, on the combination of “nucleon physics,” expressed by form factors, and “nuclear physics,” expressed by a nuclear model. It is important to get a good handle on both. We present a fully analytic implementation of the correlated Fermi gas model for electron-nucleus and charge-current quasielastic neutrino-nucleus scattering. The implementation is used to compare separately form factors and nuclear model effects for both electron-carbon and neutrino-carbon scattering data. Published by the American Physical Society 2025

Bhattacharya, Bhubanjyoti (ORCID:000000032238321X)↗