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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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NASA NTRS2018

Current Activities in the Advanced Exploration Systems ISRU Project

Media Filter MOXIE support: completed flow performance tests and initial dust loading tests of the MOXIE HEPA filter in the Mars Flow Loop Designed and fabricated prototype full-scale scroll filter for testing of renewable filter performance Mars Flow Loop upgrades: installed more sensitive instrumentation, improved imaging, and increased run duration capability Electrostatic Precipitator (ESP) Plasma-physics based model predicts particle charge and trajectory Characterizing dust environment from fluidized-bed injection dust environment using laser sheet visualization and Fine Particle Analyzer Sabatier Design Study Defined the Sabatier design space, including reactor type, thermal management, gas recycling/separation Modeled Sabatier systems with one or two reactors with different types of thermal management Adding thermal management schemes and recycling and gas separation to model Catalyst Screening Performing compression testing on new and used catalyst pellets Performing vibration testing on different catalyst pellet types under different load conditions Preparing to test catalysts for performance and degradation

In-Situ Resource Utilization↗
NASA NTRS2020

Orbit Selection for the Proposed Lynx Observatory Mission

The Advanced Concepts Office design team performed several analyses and trades in support of orbit selection for the proposed Lynx mission, an x-ray observatory being submitted to the Astro2020 Decadal Survey. Though the descriptions in this Technical Memorandum (TM) focus on the Lynx mission, the approach and process for selecting the final orbit is applicable to a variety of proposed science and exploration missions. To select the best orbit for the Lynx science, mission designers assembled a team of subsystem and discipline experts, in addition to mission analysts, to evaluate several candidate orbits. These discipline experts included members of the science and instrument team, power and avionics, thermal, propulsion, and environments. The goal was to clearly show the benefits and weaknesses of each orbit in the trade space and provide sound justification for the final selection. Discipline experts conducted trades and evaluated the results using a variety of methods including engineering judgement, rough estimates, and detailed calculations, and rolled the results into a final grade using a weighted grading method. The orbit options could then be ranked. The principal investigator (PI) for the mission, along with the science team, was given the task of final orbit selection. The result of the trades indicated that a halo orbit about the second Sun-Earth Lagrange point (SE-L2), similar to the planned orbit for the James Webb Space Telescope (JWST), was the best choice for the Lynx mission. Details of how the team arrived at this selection are below.

Hopkins, R. C.↗
NASA NTRS2015

The Impact of Radiation Damage on Photon Counting with an EMCCD for the WFIRST-AFTA Coronagraph

WFIRST-AFTA is a 2.4m class NASA observatory designed to address a wide range of science objectives using two complementary scientific payloads. The Wide Field Instrument (WFI) offers Hubble quality imaging over a 0.28 square degree field of view, and will gather NIR statistical data on exoplanets through gravitational microlensing. The second instrument is a high contrast coronagraph that will carry out the direct imaging and spectroscopic analysis of exoplanets, providing a means to probe the structure and composition of planetary systems. The coronagraph instrument is expected to operate in low photon flux for long integration times, meaning all noise sources must be kept to a minimum. In order to satisfy the low noise requirements, the Electron Multiplication (EM)-CCD has been baselined for both the imaging and spectrograph cameras. The EMCCD was selected in comparison with other candidates because of its low effective electronic read noise at sub-electron values with appropriate multiplication gain setting. The presence of other noise sources, however, such as thermal dark signal and Clock Induced Charge (CIC), need to be characterised and mitigated. In addition, operation within a space environment will subject the device to radiation damage that will degrade the Charge Transfer Efficiency (CTE) of the device throughout the mission lifetime. Here we present our latest results from pre- and post-irradiation testing of the e2v CCD201-20 BI EMCCD sensor, baselined for the WFIRST-AFTA coronagraph instrument. A description of the detector technology is presented, alongside considerations for operation within a space environment. The results from a room temperature irradiation are discussed in context with the nominal operating requirements of AFTA-C and future work which entails a cryogenic irradiation of the CCD201-20 is presented.

Peddada, Pavani↗
NASA NTRS2000

Modeling Heat-Transfer in Animal Habitats in the Shuttle Orbiter Middeck

A mathematical model has been developed to evaluate the heat transfer characteristics of an Animal Enclosure Module (AEM) in the microgravity environment. The AEM is a spaceflight habitat that provides life support for up to six rodents in the Space Shuttle Middeck. Currently, temperatures within the AEM are recorded in real time using a solid state data recorder; however, the data are only available for analysis post-flight. This temperature information is useful for characterizing the thermal environment of the AEM for researchers, but is unavailable during flight operations. Because animal health in microgravity is directly linked to the thermal environment, the ability to predict internal AEM temperatures is extremely useful to life science researchers. NASA flight crews typically carry hand-held temperature measurement devices which allow them to provide ground researchers with near real time readings of AEM inlet temperature; however, higher priority operations limit the frequency at which these measurements can be made and subsequently downlinked. The mathematical model developed allows users to predict internal cage volume temperatures based on knowledge of the ambient air temperature entering the AEM air intake ports. Additionally, an average convective heat transfer coefficient for the AEM has been determined to provide engineers with the requisite information to facilitate future design improvements and product upgrades. The model has been validated using empirical data from a series of three Space Shuttle missions.

Eodice, Michael T.↗
NASA NTRS1982

Role of IAC in large space systems thermal analysis

Computer analysis programs to evaluate critical coupling effects that can significantly influence spacecraft system performance are described. These coupling effects arise from the varied parameters of the spacecraft systems, environments, and forcing functions associated with disciplines such as thermal, structures, and controls. Adverse effects can be expected to significantly impact system design aspects such as structural integrity, controllability, and mission performance. One such needed design analysis capability is a software system that can integrate individual discipline computer codes into a highly user-oriented/interactive-graphics-based analysis capability. The integrated analysis capability (IAC) system can be viewed as: a core framework system which serves as an integrating base whereby users can readily add desired analysis modules and as a self-contained interdisciplinary system analysis capability having a specific set of fully integrated multidisciplinary analysis programs that deal with the coupling of thermal, structures, controls, antenna radiation performance, and instrument optical performance disciplines.

Jones, G. K.↗
NASA NTRS1988

Characterization of a graphite epoxy optical bench during thermal vacuum cycling

In-situ monitoring of the Wide-Field/Planetary Camera, a Hubble Space Telescope science instrument, was performed in a vacuum environment to better understand the formation of ice on cooled optical detectors. Several diagnostic instruments were mounted on an access plate to view the interior of the instrument housing and the graphite epoxy optical bench. The instrumentation chosen and the rationale for choosing the instrumentation are discussed. In addition, the performance of the instrumentation during monitoring operations is discussed.

Hansen, Patricia A.↗
NASA NTRS1992

Unsteady spot heating of a drop in a microgravity environment

The unsteady localized spot heating of a liquid drop under zero-g conditions is examined theoretically. This pertains to space experiments to measure thermal properties of materials and the purpose here is to predict the thermal behavior of such systems. Spot heating can be achieved by a laser beam focused on a small region of the drop surface. The present theoretical model deals with situations of weak Marangoni flows, whereby the thermal transport is conduction dominated. The heat flow in the drop is treated as unsteady while the surrounding gaseous region is considered to be quasisteady. The ensuing thermally driven flow is analyzed in the Stokes regime.

Sadhal, Satwindar Singh↗
NASA NTRSDate not supplied

Estimation of End-of-Life Solar Absorptivity for Complex, Multi-Phased Space Missions

Solar absorptivity degradation over time is an important contributor to the thermal performance of a spacecraft at the end of its life. When environments are complex and include many different factors known to impact solar absorptivity degradation, such as UV, charged particles, contamination, or lunar dust coverage, combining data from several different studies can be done to estimate total degradation. While the most conservative way is to stack delta absorptivity from each factor to come up with a total delta, this may be overly conservative for long or complex missions with multiple mission phases. As absorptivity increases the rate of degradation decreases, and synergistic effects need to be taken into account. In this report an alternate method is proposed using Gateway materials as an example. This method determines which environmental factor will be dominant at what time (such as contamination or charged particles) and uses that degradation rate for that mission phase. For the next mission phase, the new absorptivity can be used instead of the original BOL absorptivity to determine degradation rate. This approach prevents overestimating optical degradation when considering degradation from interconnected sources.

Brandon Michael Hoffmann↗
NASA NTRS2026

Mechanical Properties of Carbon Fiber Reinforced Composites Exposed to Cryogenic Conditions and Space Radiation via Simulation and Testing

As NASA missions extend beyond low Earth orbit, increasing reliance is placed on carbon fiber reinforced polymer (CFRP) composites for spacecraft structures where mass efficiency, durability, and long-term reliability are critical. In service, these materials are subjected to a combination of ultraviolet radiation, vacuum, ionizing radiation, atomic oxygen, and extreme thermal excursions under sustained mechanical loading. Flight systems such as the Boeing Starliner and SpaceX Dragon employ external composite structures that will experience these environments for extended durations. Although prior spaceflight and ground studies have reported limited changes in bulk mechanical properties, the synergistic effects of these environments on composite microstructure, particularly at the fiber matrix interphase, remain insufficiently characterized and represent a potential qualification and reliability risk. This study investigates the effects of short-term cryogenic exposure on a radiation shielding carbon epoxy composite, SC2020, as a ground-based analog for space relevant thermal extremes. The SC2020 material system has previously flown on the International Space Station under the Materials International Space Station Experiment (MISSE) program. Composite specimens were exposed to liquid nitrogen for 6 and 24 hours and evaluated using a multiscale characterization framework that combined ASTM D3039 tensile testing, Atomic Force Microscopy (AFM) based interphase analysis, and helium gas permeability measurements. Tensile testing showed no statistically significant or permanent degradation in global strength or modulus following cryogenic exposure. In contrast, AFM measurements revealed reductions in interphase modulus, weakened adhesion, and increased nanoscale heterogeneity, indicating localized degradation mechanisms not captured by conventional bulk testing. Gas permeability measurements showed a progressive increase in helium diffusion with exposure duration, consistent with micro-void formation or partial interfacial debonding. The results indicate that cryogenic exposure initiates degradation at the fiber matrix interphase while leaving global mechanical properties largely unchanged over short durations. These findings underscore the importance of multiscale diagnostics for identifying early-stage damage mechanisms that may influence long term performance and qualification margins for spaceflight composite structures. The data presented establish a cryogenic baseline for comparison with forthcoming MISSE flight exposure results and support ongoing NASA Established Program to Stimulate Competitive Research (EPSCoR) efforts aimed at improving composite qualification methodologies, risk assessment, and reliability prediction for space environments.

composite reliability↗
NASA NTRS2018

Chapter 6: Materials for Spacecraft

The general knowledge in this chapter is intended for a broad variety of spacecraft: manned or unmanned, low Earth to geosynchronous orbit, cis-lunar, lunar, planetary, or deep space exploration. Materials for launch vehicles are covered in chapter 7. Materials used in the fabrication of spacecraft hardware should be selected by considering the operational requirements for the particular application and the design engineering properties of the candidate materials. The information provided in this chapter is not intended to replace an in-depth materials study but rather to make the spacecraft designer aware of the challenges for various types of materials and some lessons learned from more than 50 years of spaceflight. This chapter discusses the damaging effects of the space environment on various materials and what has been successfully used in the past or what may be used for a more robust design. The material categories covered are structural, thermal control for on-orbit and re-entry, shielding against radiation and meteoroid/space debris impact, optics, solar arrays, lubricants, seals, and adhesives. Spacecraft components not directly exposed to space must still meet certain requirements, particularly for manned spacecraft where toxicity and flammability are concerns. Requirements such as fracture control and contamination control are examined, with additional suggestions for manufacturability. It is important to remember that the actual hardware must be tested to understand the real, "as-built" performance, as it could vary from the design intent. Early material trades can overestimate benefits and underestimate costs. An example of this was using graphite/epoxy composite in the International Space Station science racks to save weight. By the time the requirements for vibration isolation, Space Shuttle frequencies, and experiment operations were included, the weight savings had evaporated.

Finckenor, Miria M.↗
NASA NTRS2009

Overview of Materials International Space Station Experiment 7B

Materials International Space Station Experiment 7B (MISSE 7B) is the most recent in a series of experiments flown on the exterior of International Space Station for the purpose of determining the durability of materials and components in the space environment. A collaborative effort among the Department of Defense, the National Aeronautics and Space Administration, industry, and academia, MISSE 7B will be flying a number of NASA experiments designed to gain knowledge in the area of space environmental effects to mitigate risk for exploration missions. Consisting of trays called Passive Experiment Containers, the suitcase sized payload opens on hinges and allows active and passive experiments contained within to be exposed to the ram and wake or zenith and nadir directions in low Earth orbit, in essence, providing a test bed for atomic oxygen exposure, ultraviolet radiation exposure, charged particle radiation exposure, and thermal cycling. New for MISSE 7B is the ability to monitor experiments actively, with data sent back to Earth via International Space Station communications. NASA?s active and passive experiments cover a range of interest for the Agency. Materials relevant to the Constellation Program include: solar array materials, seal materials, and thermal protection system materials. Materials relevant to the Exploration Technology Development Program include: fabrics for spacesuits, materials for lunar dust mitigation, and new thermal control coatings. Sensors and components on MISSE 7B include: atomic oxygen fluence monitors, ultraviolet radiation sensors, and electro-optical components. In addition, fundamental space environmental durability science experiments are being flown to gather atomic oxygen erosion data and thin film polymer mechanical and optical property data relevant to lunar lander insulation and the James Web Space Telescope. This paper will present an overview of the NASA experiments to be flown on MISSE 7B, along with a summary of the thermal environment to be expected during the 1 yr mission scheduled for launch in 2009.

Jaworske, Donald A.↗
NASA NTRS2018

Copper-Water and Hybrid Aluminum-Ammonia Heat Pipes for Spacecraft Thermal Control Applications

Copper-water heat pipes are commonly used for thermal management of electronics systems on earth and aircraft, but have not been used in spacecraft thermal control applications to date, due to the satellite industry's requirement that any device or system be successfully tested in a microgravity environment prior to adoption. Recently, Advanced Cooling Technologies Inc., (ACT), NASA Marshall Space Flight Center, and the International Space Station office at NASA's Johnson Space Center demonstrated flight heritage in Low-Earth Orbit. The testing was conducted aboard the International Space Station (ISS) under the Advanced Passive Thermal eXperiment (APTx) project. The heat pipes were embedded in a high conductivity (HiK"TM") aluminum base plate and subject to a variety of thermal tests over a temperature range of -10 to 38 ºC for a ten-day period. Results showed excellent agreement with both predictions and ground tests. In addition, novel hybrid wick aluminum-ammonia heat pipes are developed to handle heat flux requirements for spacecraft thermal control applications. The 5-10 W/cm2 heat density limitation of aluminum-ammonia grooved heat pipes has been a fundamental limitation in the current design for space applications. The recently demonstrated 50 W/cm2 capability of the hybrid high heat flux heat pipes provides a realistic means of managing the high heat density anticipated for the next generation space designs.

Ababneh, Mohammed T.↗
NASA NTRS2018

Copper-Water and Hybrid Aluminum-Ammonia Heat Pipes for Spacecraft Thermal Control Applications

Copper-water heat pipes are commonly used for thermal management of electronics systems on earth and aircraft, but have not been used in spacecraft thermal control applications to date, due to the satellite industry's requirement that any device or system be successfully tested in a microgravity environment prior to adoption. Recently, Advanced Cooling Technologies Inc., (ACT), NASA Marshall Space Flight Center, and the International Space Station office at NASA's Johnson Space Center demonstrated flight heritage in Low-Earth Orbit. The testing was conducted aboard the International Space Station (ISS) under the Advanced Passive Thermal eXperiment (APTx) project. The heat pipes were embedded in a high conductivity (HiK "TM") aluminum base plate and subject to a variety of thermal tests over a temperature range of -10 to 38 C for a ten-day period. Results showed excellent agreement with both predictions and ground tests. In addition, novel hybrid wick aluminum-ammonia heat pipes are developed to handle heat flux requirements for spacecraft thermal control applications. The 5-10 W/cm2 heat density limitation of aluminum-ammonia grooved heat pipes has been a fundamental limitation in the current design for space applications. The recently demonstrated 50W/cm2 capability of the hybrid high heat flux heat pipes provides a realistic means of managing the high heat density anticipated for the next generation space designs.

Ababneh, Mohammed T.↗
NASA NTRSDate not supplied

Evaluation of Coatings for the Electrodynamic Dust Shield Application on Thermal Radiators

Space dust acts as a blackbody, becoming hot if left in direct sunlight. This is a problem for thermal radiators used in space missions, where the main function is to radiate heat away from an object. If dust lands on the thermal radiator, the unit will less effectively reject heat, and it will overheat, leading to electrical or system failure. The current state-of-the-art in active dust mitigation is the Electrodynamic Dust Shield (EDS) which uses an electric field generated by alternating high positive and negative voltages (low current) to eject the charged dust off surfaces. An EDS made from copper coated Kapton is an ideal candidate to be bonded to a thermal radiator and coated with a low solar absorptance, high heat-emitter coating. This work compares the dust removal of copper-Kapton EDSs covered with different thermal radiator coatings in air and vacuum environments. The coatings include AZ-93 paint, Thermal Bright, and Solar White, a coating developed by the Applied Physics Lab (APL) at NASA Kennedy Space Center (KSC). The resistance and the thickness of the various coatings impact how well it works as an insulative layer for the EDS. Preliminary results indicate that Solar White may have better properties for dust removal and thermal rejection than the other coatings.

Krystal L. Acosta↗
NASA NTRS2017

Development of NASA's Sample Cartridge Assembly: Summary of GEDS Design, Development Testing, and Thermal Analyses

NASA's Sample Cartridge Assembly (SCA) project is responsible for designing and validating a payload that contains materials research samples in a sealed environment. The SCA will be heated in the European Space Agency's (ESA) Low Gradient Furnace (LGF) that is housed inside the Material Science Research Rack (MSRR) located on the International Space Station (ISS). The first Principle Investigator (PI) to utilize the SCA will focus on Gravitational Effects on Distortion in Sintering (GEDS) research. This paper will give a summary of the design and development test effort for the GEDS SCA and will discuss the role of thermal analysis in developing test profiles to meet the science and engineering requirements. Lessons learned will be reviewed and salient design features that may differ for each PI will be discussed.

O'Connor, Brian↗
NASA NTRS2011

A Computational Methodology for Simulating Thermal Loss Testing of the Advanced Stirling Convertor

Convertor and generator testing is carried out in tests designed to characterize convertor performance when subjected to environments intended to simulate launch and space conditions. The value of net heat input must be known in order to calculate convertor efficiency and to validate convertor performance. Specially designed test hardware was used to verify and validate a two step methodology for the prediction of net heat input. This lessons learned from these simulations have been applied to previous convertor simulations. As heat is supplied to the convertors, electric power is produced and measured. Net heat input to the convertor is one parameter that will contribute to the calculation of efficiency. This parameter is not measured directly. Insulation Loss. Determine the current status of the thermal conductivity of the micro-porous insulation. - Match heat source and hot end temperatures. - Match temperature difference across Kaowool insulation

Reid, Terry V.↗
NASA NTRS1987

The NESSUS finite element code

The objective of this development is to provide a new analysis tool which integrates the structural modeling versatility of a modern finite element code with the latest advances in the area of probabilistic modeling and structural reliability. Version 2.0 of the NESSUS finite element code was released last February, and is currently being exercised on a set of problems which are representative of typical Space Shuttle Main Engine (SSME) applications. NESSUS 2.0 allows linear elastostatic and eigenvalue analysis of structures with uncertain geometry, material properties and boundary conditions, which are subjected to a random mechanical and thermal loading environment. The NESSUS finite element code is a key component in a broader software system consisting of five major modules. NESSUS/EXPERT is an expert system under development at Southwest Research Institute, with the objective of centralizing all component-specific knowledge useful for conducting probabilistic analysis of typical Space Shuttle Main Engine (SSME) components. NESSUS/FEM contains the finite element code used for the structural analysis and parameter sensitivity evaluation of these components. The task of parametrizing a finite element mesh in terms of the random variables present is facilitated with the use of the probabilistic data preprocessor in NESSUS/PRE. An external database file is used for managing the bulk of the data generated by NESSUS/FEM.

Dias, J. B.↗
NASA NTRS2012

Adhesion Between Volcanic Glass and Spacecraft Materials in an Airless Body Environment

The successful exploration of airless bodies, such as the Earth s moon, many smaller moons of the outer planets (including those of Mars) and asteroids, will depend on the development and implementation of effective dust mitigation strategies. The ultrahigh vacuum environment (UHV) on the surfaces of these bodies, coupled with constant ion and photon bombardment from the Sun and micrometeorite impacts (space weathering), makes dust adhesion to critical spacecraft systems a severe problem. As a result, the performance of thermal control surfaces, photovoltaics and mechanical systems can be seriously degraded even to the point of failure. The severe dust adhesion experienced in these environments is thought to be primarily due to two physical mechanisms, electrostatic attraction and high surface energies, but the dominant of these has yet to be determined. The experiments presented here aim to address which of these two mechanisms is dominant by quantifying the adhesion between common spacecraft materials (polycarbonate, FEP and PTFE Teflon, (DuPont) Ti-6-4) and a synthetic noritic volcanic glass, as a function of surface cleanliness and triboelectric charge transfer in a UHV environment. Adhesion force has been measured between pins of spacecraft materials and a plate of synthetic volcanic glass by determining the pull-off force with a torsion balance. Although no significant adhesion is observed directly as a result of high surface energies, the adhesion due to induced electrostatic charge is observed to increase with spacecraft material cleanliness, in some cases by over a factor of 10, although the increase is dependent on the particular material pair. The knowledge gained by these studies is envisioned to aid the development of new dust mitigation strategies and improve existing strategies by helping to identify and characterize mechanisms of glass to spacecraft adhesion for norite volcanic glass particles. Furthermore, the experience of the Apollo missions revealed that dust mitigation strategies must be subjected to high fidelity tests. To facilitate the effectiveness of ground-based testing of mitigation strategies, the issue of a pressure limit for high fidelity tests will be addressed.

Berkebile, Stephen↗