Solar Array (Radiated/Non-Radiated): Materials Characterization and Cryogenic Thermal Cycling Qualification for the Planned Europa Clipper Mission (ECM)
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Ramesham, Rajeshuni↗
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Results for “Thermal characterization”
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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Design of a Thermal Precipitator for the Characterization of Smoke Particles from Common Spacecraft Materials
A thermal precipitator (TP) was designed to collect smoke aerosol particles for microscopic analysis in fire characterization research. Information on particle morphology, size and agglomerate structure obtained from these tests supplements additional aerosol data collected. Modeling of the thermal precipitator throughout the design process was performed with the COMSOL Multiphysics finite element software package, including the Eulerian flow field and thermal gradients in the fluid. The COMSOL Particle Tracing Module was subsequently used to determine particle deposition. Modeling provided optimized design parameters such as geometry, flow rate and temperatures. The thermal precipitator was built and testing verified the performance of the first iteration of the device. The thermal precipitator was successfully operated and provided quality particle samples for microscopic analysis, which furthered the body of knowledge on smoke particulates. This information is a key element of smoke characterization and will be useful for future spacecraft fire detection research.
Smoke↗
Cryogenic Insulation Standard Data and Methodologies Project
Extending some recent developments in the area of technical consensus standards for cryogenic thermal insulation systems, a preliminary Inter-Laboratory Study of foam insulation materials was performed by NASA Kennedy Space Center and LeTourneau University. The initial focus was ambient pressure cryogenic boil off testing using the Cryostat-400 flat-plate instrument. Completion of a test facility at LETU has enabled direct, comparative testing, using identical cryostat instruments and methods, and the production of standard thermal data sets for a number of materials under sub-ambient conditions. The two sets of measurements were analyzed and indicate there is reasonable agreement between the two laboratories. Based on cryogenic boiloff calorimetry, new equipment and methods for testing thermal insulation systems have been successfully developed. These boiloff instruments (or cryostats) include both flat plate and cylindrical models and are applicable to a wide range of different materials under a wide range of test conditions. Test measurements are generally made at large temperature difference (boundary temperatures of 293 K and 78 K are typical) and include the full vacuum pressure range. Results are generally reported in effective thermal conductivity (ke) and mean heat flux (q) through the insulation system. The new cryostat instruments provide an effective and reliable way to characterize the thermal performance of materials under subambient conditions. Proven in through thousands of tests of hundreds of material systems, they have supported a wide range of aerospace, industry, and research projects. Boiloff testing technology is not just for cryogenic testing but is a cost effective, field-representative methodology to test any material or system for applications at sub-ambient temperatures. This technology, when adequately coupled with a technical standards basis, can provide a cost-effective, field-representative methodology to test any material or system for applications at sub-ambient to cryogenic temperatures. A growing need for energy efficiency and cryogenic applications is creating a worldwide demand for improved thermal insulation systems for low temperatures. The need for thermal characterization of these systems and materials raises a corresponding need for insulation test standards and thermal data targeted for cryogenic-vacuum applications. Such standards have a strong correlation to energy, transportation, and environment and the advancement of new materials technologies in these areas. In conjunction with this project, two new standards on cryogenic insulation were recently published by ASTM International: C1774 and C740. Following the requirements of NPR 7120.10, Technical Standards for NASA Programs and Projects, the appropriate information in this report can be provided to the NASA Chief Engineer as input for NASA's annual report to NIST, as required by OMB Circular No. A-119, describing NASA's use of voluntary consensus standards and participation in the development of voluntary consensus standards and bodies.
Technology Portfolio System↗
Pre-Launch Radiometric Characterization of JPSS-1 VIIRS Thermal Emissive Bands
Pre-launch characterization and calibration of the thermal emissive spectral bands on the Joint Polar Satellite System (JPSS-1) Visible Infrared Imaging Radiometer Suite (VIIRS) is critical to ensure high quality data products for environmental and climate data records post-launch. A comprehensive test program was conducted at the Raytheon El Segundo facility in 2013-2014, including extensive environmental testing. This work is focused on the thermal band radiometric performance and stability, including evaluation of a number of sensor performance metrics and estimation of uncertainties. Analysis has shown that JPSS-1 VIIRS thermal bands perform very well in relation to their design specifications, and comparisons to the Suomi National Polar-orbiting Partnership (SNPP) VIIRS instrument have shown their performance to be comparable.
Thermal Bands↗
Thermally reversible gels in electrophoresis. I - Matrix characterization
Two series of thermally reversible hydrogen-bonded gels have been characterized: (5 pct) PVA-(4 pct) PEG and (5 pct) PVA-(0.04 pct) borate gels. They both have extremely low melting points (16-17 C) and could be of potential interest for recovery of proteins after preparative electrophoresis. The PVA-borate gels can be exploited in the pH range 7-11 by progressively increasing the borate content in the pH interval 8 to 7 and concomitantly decreasing the borate levels in the pH zone 8 to 11. It is hypothesized that the low melting point of these gels is due to the fact that they are sparingly and sparsely hydrogen bonded along the PVA chain: on the average, 1 OH group out of 3 or 4 OH groups in the PVA polymer should be engaged in H-bond formation.
Righetti, Pier Giorgio↗
The Search for Water and Other Volatile-bearing Phases on Mars: Mauna Kea Volcano as an Analog
Over the past 5 years, we have conducted field studies on the summit cones of Mauna Kea Volcano in Hawaii. Basaltic materials on several of these summit cones have been significantly altered by hydrothermal activity, whereas other summit cones have not undergone extensive aqueous alteration. These summit cones provide an important environment to study analogs of Martian surface alteration materials and analog surface processes (i.e., hydrothermal alteration, palagonitization. In on-going research, we have characterized the thermal and evolved gas behaviors of volatile-bearing reference minerals at reduced pressures in support of TEGA. We have expanded those studies to characterize the thermal and evolved gas behaviors of Mauna Kea samples as an analog for Mars surface materials. These samples were chosen for two reasons. First, many have chemical and spectral properties similar to what we see from remote sensing data from the Martian surface. Second, these samples have a range of mineralogical and chemical properties, ranging from simple to very complex; hence it will be challenging to characterize their thermal and evolved gas behaviors and to provide a context for their geological evolution. However, these types of studies are absolutely critical to understanding relevant geologic processes on Mars during robotic missions to the surface.
Ming, D. W.↗
Microstructural characterization of the HRSI thermal protection system for space shuttle
Components of the space shuttle high temperature reusable surface insulation (HRSI) system were microscopically characterized, both separately and as a system, to obtain information needed for stress analysis models of the thermal protection system. A tension specimen of the HRSI system was loaded in steps and was microscopically observed at each load condition to demonstrate the tension failure mode associated with strain isolation pad (SIP) behavior. A local failure occurred which should be associated with transfer of load through transverse fibers in the SIP. Stress concentrations attributed to the SIP behavior necessitated strengthening of the HRSI by densification of the RSI at the bondline. An HRSI tile was microscopically characterized after the densification process. The densified surface layer blended into the RSI which caused a gradual change in density. The gradation in density does not appear to represent a sharp discontinuity in elastic modulus between the densified layer and the parent material.
Ransone, P. O.↗
A Thermal Precipitator for Fire Characterization Research
Characterization of the smoke from pyrolysis of common spacecraft materials provides insight for the design of future smoke detectors and post-fire clean-up equipment on the International Space Station. A thermal precipitator was designed to collect smoke aerosol particles for microscopic analysis in fire characterization research. Information on particle morphology, size and agglomerate structure obtained from these tests supplements additional aerosol data collected. Initial modeling for the thermal precipitator design was performed with the finite element software COMSOL Multiphysics, and includes the flow field and heat transfer in the device. The COMSOL Particle Tracing Module was used to determine particle deposition on SEM stubs which include TEM grids. Modeling provided optimized design parameters such as geometry, flow rate and temperatures. Microscopy results from fire characterization research using the thermal precipitator are presented.
Meyer, Marit↗
Characterizing the Physical and Thermal Properties of Planetary Regolith at Low Temperatures
The success or failure of in-situ resource utilization for planetary surface exploration-whether for science, colonization, or commercialization-relies heavily on the design and implementation of systems that can effectively process planetary regolith and exploit its potential benefits. In most cases, this challenge necessarily includes the characterization of regolith properties at low temperatures (cryogenic). None of the nearby solar system destinations of interest, such as the moon, Mars and asteroids, possess a sufficient atmosphere to sustain the consistently "high" surface temperatures found on Earth. Therefore, they can experience permanent cryogenic temperatures or dramatic cyclical changes in surface temperature. Characterization of physical properties (e.g., specific heat, thermal and electrical conductivity) over the entire temperature profile is important when planning a mission to a planetary surface; however, the impact on mechanical properties due to the introduction of icy deposits must also be explored in order to devise effective and robust excavation technologies. The Granular Mechanics and Regolith Operations Laboratory and the Cryogenics Test Laboratory at NASA Kennedy Space Center are developing technologies and experimental methods to address these challenges and to aid in the characterization of the physical and mechanical properties of regolith at cryogenic temperatures. This paper will review the current state of knowledge concerning planetary regolith at low temperature, including that of icy regolith, and describe efforts to manipulate icy regolith through novel penetration and excavation techniques.
Characterizing the Physical and Thermal Properties↗
Near Net Shape Fabrication and Characterization of Cermet Nuclear Thermal Propulsion Fuel Forms
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fabriaction↗
Using the thermal infrared multispectral scanner (TIMS) to estimate surface thermal responses
A series of measurements was conducted over the H.J. Andrews, Oregon, experimental coniferous forest, using airborne thermal infrared multispectral scanner (TIMS). Flight lines overlapped, with a 28-min time difference between flight lines. Concurrent radiosonde measurements of atmospheric profiles of air temperature and moisture were used for atmospheric radiance corrections of the TIMS data. Surface temperature differences over time between flight lines were used to develop thermal response numbers (TRNs) which characterized the thermal response (in KJ/sq m/C, where K is the measured incoming solar radiation) of the different surface types. The surface types included a mature forest (canopy dominated by dense crowns of Pseudosuga menziesii, with a secondary canopy of dense Tsuga heterophylla, and also a tall shrub layer of Acer circinatum) and a two-year-old clear-cut. The temperature distribution, within TIMS thermal images was found to reflect the surface type examined. The clear-cut surface had the lowest TRN, while mature Douglas fir the highest.
Luvall, J. C.↗
The use of aircraft-based Thermal Infrared Multispectral Scanner (TIMS) data to measure surface energy budgets on a landscape scale
A series of Thermal Infrared Multispectral Scanner Data (TIMS) was collected over the H. J. Andrews experimental forest in western Oregon and at the Coweeta Hydrologic Laboratory in North Carolina. Flight lines were overlapped with an 8 to 28 minute time difference between flight lines. Concurrent radiosonde measurements of atmospheric profiles of air and dew point temperatures provided inputs to LOWTRAN6 for atmospheric radiance corrections of the TIMS data. Surface temperature differences over time between flight lines allowed the development of thermal response numbers (TRN) which characterized the thermal response of the different surface types. The polygons containing mostly soil and bare rock had the lowest TRN whereas the forested polygons were the highest. Results indicate that forest canopy temperatures measured by the TIMS are comparable to needle thermocouples temperatures. ET models developed from the TIMS data obtained similar ET rates as those using energy balance techniques.
Luvall, Jeffrey C.↗
Thermal and Evolved Gas Analysis of "Nanophase" Carbonates: Implications for Thermal and Evolved Gas Analysis on Mars Missions
Data collected by the Mars Phoenix Lander's Thermal and Evolved Gas Analyzer (TEGA) suggested the presence of calcium-rich carbonates as indicated by a high temperature CO2 release while a low temperature (approx.400-680 C) CO2 release suggested possible Mg- and/or Fe-carbonates [1,2]. Interpretations of the data collected by Mars remote instruments is done by comparing the mission data to a database on the thermal properties of well-characterized Martian analog materials collected under reduced and Earth ambient pressures [3,4]. We are proposing that "nano-phase" carbonates may also be contributing to the low temperature CO2 release. The objectives of this paper is to (1) characterize the thermal and evolved gas proper-ties of carbonates of varying particle size, (2) evaluate the CO2 releases from CO2 treated CaO samples and (3) examine the secondary CO2 release from reheated calcite of varying particle size.
Lauer, Howard V., Jr.↗
A Cryogenic Thermal Source for Detector Array Characterization
We describe the design, fabrication, and validation of a cryogenically compatible quasioptical thermal source for characterization of detector arrays. The source is constructed using a graphite-loaded epoxy mixture that is molded into a tiled pyramidal structure. The mold is fabricated using a hardened steel template produced via a wire electron discharge machining process. The absorptive mixture is bonded to a copper backplate enabling thermalization of the entire structure and measurement of the source temperature. Measurements indicate that the reflectance of the source is less than 0.001 across a spectral band extending from 75 to 330 gigahertz.
Chuss, David T.↗
LANDSAT 9 Thermal Infrared Sensor 2 Characterization Plan Overview
Landsat 9 will continue the Landsat data record into its fifth decade with a near-copy build of Landsat 8 with launch scheduled for December 2020. The two instruments on Landsat 9 are Thermal Infrared Sensor-2 (TIRS-2) and Operational Land Imager-2 (OLI-2). TIRS-2 is a two-channel pushbroom imager with a 15-degree field of view that will have a 16-day measurement cadence from its nominal 705-km orbit altitude. Its carefully developed instrument performance requirements and associated characterization plan will result in stable and well-understood science-quality imagery that will be used for environmental, economic and legal applications. This paper will present a summary of the plan for TIRS-2 prelaunch characterization at the component, subsystem, and instrument level.
thermal infrared remote sensing↗
Impedance Matched Absorptive Thermal Blocking Filters
We have designed, fabricated and characterized absorptive thermal blocking filters for cryogenic microwave applications. The transmission line filter's input characteristic impedance is designed to match 50Ω and its response has been validated from 0-to-50GHz. The observed return loss in the 0-to-20GHz design band is greater than 20 dB and shows graceful degradation with frequency. Design considerations and equations are provided that enable this approach to be scaled and modified for use in other applications.
thermal blocking filters↗
Impedance Matched Absorptive Thermal Blocking Filters
We have designed, fabricated and characterized absorptive thermal blocking filters for cryogenic microwave applications. The transmission line filter's input characteristic impedance is designed to match 50 Omega and its response has been validated from 0-to-50GHz. The observed return loss in the 0-to-20GHz design band is greater than 20 dB and shows graceful degradation with frequency. Design considerations and equations are provided that enable this approach to be scaled and modified for use in other applications.
cryogenic microwave applications↗
Embedded Thermal Control for Subsystems for Next Generation Spacecraft Applications
Thermal Fluids and Analysis Workshop, Silver Spring MD NCTS 21070-15. NASA, the Defense Department and commercial interests are actively engaged in developing miniaturized spacecraft systems and scientific instruments to leverage smaller cheaper spacecraft form factors such as CubeSats. This paper outlines research and development efforts among Goddard Space Flight Center personnel and its several partners to develop innovative embedded thermal control subsystems. Embedded thermal control subsystems is a cross cutting enabling technology integrating advanced manufacturing techniques to develop multifunctional intelligent structures to reduce Size, Weight and Power (SWaP) consumption of both the thermal control subsystem and overall spacecraft. Embedded thermal control subsystems permit heat acquisition and rejection at higher temperatures than state of the art systems by employing both advanced heat transfer equipment (integrated heat exchangers) and high heat transfer phenomena. The Goddard Space Flight Center Thermal Engineering Branch has active investigations seeking to characterize advanced thermal control systems for near term spacecraft missions. The embedded thermal control subsystem development effort consists of fundamental research as well as development of breadboard and prototype hardware and spaceflight validation efforts. This paper will outline relevant fundamental investigations of micro-scale heat transfer and electrically driven liquid film boiling. The hardware development efforts focus upon silicon based high heat flux applications (electronic chips, power electronics etc.) and multifunctional structures. Flight validation efforts include variable gravity campaigns and a proposed CubeSat based flight demonstration of a breadboard embedded thermal control system. The CubeSat investigation is technology demonstration will characterize in long-term low earth orbit a breadboard embedded thermal subsystem and its individual components to develop optimized operational schema.
Spacecraft Systems↗