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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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A nonporous membrane based on the polymerization of 2,3-dihydrofuran followed by crosslinking in situ was prepared. The material is compatible with rechargeable Li battery components and, when swollen with an appropriate solvent such as tetrahydrofuran, exhibits separator resistance and Li transport equivalent to Celgard.
The formation of fullerenes C 60 and C 7O is known to occur in premixed laminar benzene/oxygen/argon flames operated at reduced pressures. High resolution transmission electron microscopy (HRTEM) images of material collected from these flames has identified a variety of multishelled nanotubes and fullerene 'onions' as well as some trigonous structures. These fullerenes and nanostructures resemble the material that results from commercial fullerene production systems using graphite vaporization. As a result, combustion is an interesting method for fullerenes synthesis. If commercial scale operation is to be considered, the use of diffusion flames might be safer and less cumbersome than premixed flames. However, it is not known whether diffusion flames produce the types and yields of fullerenes obtained from premixed benzene/oxygen flames. Therefore, the formation of fullerenes and carbon nanostructures, as well as polycyclic aromatic hydrocarbons (PAH) and soot, in acetylene and benzene diffusion flames is being studied using high performance liquid chromatography (HPLC) and high resolution transmission electron microscopy (HRTEM).
The 19 technical papers developed for the AGARD Fluid Dynamics Panel (FDP) Specialists' Meeting on "Effects of Adverse Weather on Aerodynamics" held from 28th April—i May 1991 in Toulouse, France are documented in this Conference Proceedings. In addition, introductory material from the Program Chairman and the results of the Round Table Discussion held after the meeting are also included. The FDP organized this meeting to provide a timely review of the progress being made in advancing the state-of-the-art of predicting, simulating, and measuring the effects of icing, anti-icing fluids, and various forms of precipitation on the aerodynamic characteristics of flight vehicles. Topics included results from both theoretical and experimental programs and material related to procedures and regulations for certification and operation. International participation for the meeting included authors from eight nations and representatives from most of the 16 NATO nations.
Through the Artemis program, NASA intends to develop a sustainable human foothold on the Moon, ultimately paving the way for crewed exploration of Mars. The Moon's hostile environment poses numerous obstacles, including exposure to radiation, temperature extremes, micrometeoroid threats, and particularly the persistent problem of lunar dust. Lunar dust impacts nearly every aspect of surface operations through adhesion and abrasion mechanisms, with contamination from anthropogenic activities (landing, rovers) far outweighing natural phenomena. Multiple adhesion pathways contribute to surface contamination in the lunar environment, including van der Waals forces, electrostatic forces, chemical reaction, and magnetic forces from elemental iron deposits. Sharp asperities from micrometeoroid bombardment and atmospheric absence increase interaction potential and enable mechanical interlocking. Low cohesion between dust particles exacerbates these challenges, as minimal interaction potential between dust and nearby surfaces overcomes particle cohesion, causing contamination. Lunar dust adhesion mitigation technologies can be categorized as either active, requiring external energy, or passive, relying on intrinsic material properties. Ultrasonic and electrodynamic technologies have been developed to the highest technology readiness level for active approaches. Passive strategies primarily focus on surface chemistry and topography modifications. At NASA Langley Research Center, approaches include surface migration agents to reduce surface energy, topographical modification using laser ablation patterning, and tailored surface conductivity to reduce intrinsic adhesion force. Performance has been evaluated using custom-built ultrasonic and centrifuge instruments. Plume-surface interactions from lunar landers can propel micrometer-sized particles at velocities up to 1000 m s-1.8 These particles pose risks to landers, habitats and infrastructure, leading to erosion, degradation, and reduced component lifespan. A panel recovered from Surveyor III was determined to have been severely abraded because of lunar dust displaced from the Apollo 12 lunar module that landed 160 m away. The performance of metallic surfaces has been evaluated via high velocity single particle impact using the laser-induced project impact test (LIPIT) facility at the University of Utah. Peridynamics modeling, a form of continuum mechanics that uses a nonlocal approach enabling greater simulation capabilities of crack initiation and fracture, has also been utilized to gain greater insight into material response during impact events. Lunar dust contamination challenges extend to power generation systems and moving equipment. Cables, rotation stages, and other mechanisms may experience limited range of motion and reduced lifetime due to dust infiltration. NASA Langley Research Center has evaluated traditional aerospace alloys, softgoods, wear resistant ceramics, and several polymer and polymer composite materials. Test methods have included traditional techniques like Taber abrasion testing, as well as designed test configurations developed in the DUSTE (dust, ultraviolet radiation, and space thermal environmental) chamber that reproduce mechanism functions in operational environment. Beyond laboratory experiments, several flight experiments have been conducted. Materials were exposed to the low Earth orbit environment on the Materials International Space Station Experiment (MISSE) and to the lunar surface environment through the Aegis Aerospace Regolith Adherence Characterization (RAC) payload and the Honeybee Robotics PlanetVac payload. Determining lunar dust's impact on surface exploration and habitation requires comprehensive experimental and computational capabilities combined with lessons learned from initial lunar activities. Identifying the greatest environmental challenges and developing mitigation technologies provides the clearest path toward successfully, expeditiously, and efficaciously completing NASA's mission. This presentation will discuss ongoing efforts at NASA Langley Research Center and collaborator contributions to these critical objectives.
On longer range exploration missions, the mass and volume of critical hardware and consumables required to support crew will pose a big stowage challenge. This includes the hardware for the collection and storage of human metabolic solid waste. The amount of stowage needed for this hardware both before (empty) and after (full) use will be a significant burden on the overall spacecraft habitable volume, layout, and design. To help with this challenge, the National Aeronautics and Space Administration (NASA) Mars Campaign Office (MCO) Logistics Reduction (LR) Portfolio has developed a collapsible canister for the collection and containment of fecal deposits. The Alternate Fecal Canister (AFC) is a collapsible alternative to the exploration toilet Hard-sided Fecal Canister (HFC). The AFC in its empty state has a volumetric benefit to smaller vehicles on longer missions. The current designs for HFC and AFC were tested with human fecal material for odor containment at White Sands Test Facility (WSTF) where the tests on both were unsuccessful. The source of the lack of containment was isolated to a gasket used on both HFC and AFC. The gasket used was found to be open cell in design. This paper provides a summary of the materials selection and testing process to identify a replacement gasket material with the intention to replace the gaskets on both existing units as well as incorporate it into the designs going forward for future builds for exploration. Details will be provided on the design of the canisters interface with the odor bacteria lid which led to the selection of the thickness of the desired replacement. Finally, the paper will provide an update on the testing in advance of a return to WSTF for final testing and detail plans to complete testing and perform a demonstration on ISS with UWMS.
A survey of the meteoroid and space debris impacts on LDEF experiment M0003 was performed. The purpose was to document impact phenomenology and to obtain impact crater data for comparison to current debris and micrometeoroid models. The survey consists of photomicrographs of significant impacts in a variety of material types, accurate measurements of impact crater coordinates and dimensions for selected experiment surfaces and data basing of the crater data for reduction, manipulation, and comparison models. Large area surfaces which were studied include the experiment power and data system sunshields, environment exposure control canister sunshields, and the M0003 signal conditioning unit covers. Crater diameters down to 25 microns were measured and catalogued. Both leading and trailing edge surfaces were studied and compared. The results shows the different response of materials to hypervelocity impacts. Comparison of the data to curves derived from the Kessler debris model and the Cour-Palais micrometeoroid model indicates a marked tendency for overprediction of small impacts and underprediction of large impacts with there being better agreement for the medium sized impacts. Representative impact data is presented.
On longer range exploration missions, the mass and volume of critical hardware and consumables required to support crew will pose a big stowage challenge. This includes the hardware for the collection and storage of human metabolic solid waste. The amount of stowage needed for this hardware both before (empty) and after (full) use will be a significant burden on the overall spacecraft habitable volume, layout, and design. To help with this challenge, the National Aeronautics and Space Administration (NASA) Mars Campaign Office (MCO) Logistics Reduction (LR) Portfolio has developed a collapsible canister for the collection and containment of fecal deposits. The Alternate Fecal Canister (AFC) is a collapsible alternative to the exploration toilet Hard-sided Fecal Canister (HFC). The AFC in its empty state has a volumetric benefit to smaller vehicles on longer missions. The current designs for HFC and AFC were tested with human fecal material for odor containment at White Sands Test Facility (WSTF) where the tests on both were unsuccessful. The source of the lack of containment was isolated to a gasket used on both HFC and AFC. The gasket used was found to be open cell in design. This paper provides a summary of the materials selection and testing process to identify a replacement gasket material with the intention to replace the gaskets on both existing units as well as incorporate it into the designs going forward for future builds for exploration. Details will be provided on the design of the canisters interface with the odor bacteria lid which led to the selection of the thickness of the desired replacement. Finally, the paper will provide an update on the testing in advance of a return to WSTF for final testing and detail plans to complete testing and perform a demonstration on ISS with UWMS.
Cathodic materials for high energy density storage battery
The arrival of the Nanoracks Airlock to the International Space Station (ISS) has provided the ISS program the capability to dispose of common trash items. The concept of operations involved the crew bagging up those items into a trash bag and then utilizing the robotic arm and the airlock to jettison the trash bag. Because of the unknown thermal vacuum stability of some of the items, a molecular contamination concern was raised by the ISS program as the trash is exposed to vacuum upon the evacuation of air from the airlock and the robotic arm moving the airlock to its jettison location. In order to characterize the representative outgassing rates for ISS trash, thermal vacuum testing was performed at White Sands Test Facility. Trash was sorted into a “lower” outgassing bag and a “mixed” bag. The “mixed” trash bag contained more items that were suspected to be not vacuum stable. Load cells were chosen as the primary means for measuring mass loss. A sharp decay in the outgassing rate was observed in the first 30 minutes followed by a slower decay. As expected, the “mixed” bag lost more mass. While Quartz Crystal Microbalances (QCMs) are often utilized to measure long term outgassing rates and the sticking coefficients of contaminants at different operating temperatures for vacuum stable materials, these measurements proved difficult due to the amount and the inclusion of materials with suspect thermal vacuum stability. Because of high rates of material outgassing, the facility was unable to maintain the CQCM temperature setpoint of 80 K QCMs.. The QCMs operating at the warmer temperatures also saturated on occasion due to high levels of condensed matter. Though testing was able to confirm high risk of outgassing contamination for the program, true sticking coefficients could not be determined, available measurements are provided herein.
Polymer matrix composites (PMCs) offer many benefits for the aerospace industry due to their potential for weight reduction when compared to metal or ceramic based materials. Most PMCs currently in flight use thermoset matrices, however, thermoplastic resins are being explored as alternatives due to their ability to be remelted, which is of particular interest due to the potential for in-situ repair and manufacturing required in space. Most thermoplastic resins are semicrystalline polymers. The properties of semicrystalline thermoplastics are largely influenced by their crystallinity, which can vary due to many factors including thermal treatments, environmental conditions, and mechanical deformation. Monitoring the crystallinity of thermoplastic composites is key to ensuring these materials reliably meet the high demands required by space exploration. This talk discusses the use of multiple techniques such as Polarized Light Optical Microscopy and Fourier-Transform Infrared Spectroscopy to characterize the crystallinity in various thermoplastic composites, including carbon fiber reinforced PMCs and novel bio-based Martian and Lunar regolith composites designed for in-situ manufacturing. This work aims to provide the fundamental data necessary to understand the effects of crystallinity on thermoplastic PMCs, which is key to advancing their use in space applications.
The solar wind is described and its effects on surfaces are reviewed. Experimental results are given for materials subjected to simulated solar-wind bombardment. Among the effects discussed are sputtering-type erosion, chemical reaction with paint vehicles and reduction of oxide pigments, and production of lunar-surface optical characteristics in a basalt powder.
The double explosion of SN 2009ip in 2012 raises questions about our understanding of the late stages of massive star evolution. Here we present a comprehensive study of SN 2009ip during its remarkable rebrightenings. High-cadence photometric and spectroscopic observations from the GeV to the radio band obtained from a variety of ground-based and space facilities (including the Very Large Array, Swift, Fermi, Hubble Space Telescope, and XMM) constrain SN 2009ip to be a low energy (E (is) approximately 10(exp 50) erg for an ejecta mass approximately 0.5 solar mass) and asymmetric explosion in a complex medium shaped by multiple eruptions of the restless progenitor star. Most of the energy is radiated as a result of the shock breaking out through a dense shell of material located at approximately 5 × 10( exp 14) cm with M approximately 0.1 solar mass, ejected by the precursor outburst approximately 40 days before the major explosion. We interpret the NIR excess of emission as signature of material located further out, the origin of which has to be connected with documented mass-loss episodes in the previous years. Our modeling predicts bright neutrino emission associated with the shock break-out if the cosmic-ray energy is comparable to the radiated energy. We connect this phenomenology with the explosive ejection of the outer layers of the massive progenitor star, which later interacted with material deposited in the surroundings by previous eruptions. Future observations will reveal if the massive luminous progenitor star survived. Irrespective of whether the explosion was terminal, SN 2009ip brought to light the existence of new channels for sustained episodic mass loss, the physical origin of which has yet to be identified.
The Aerogel Lecture Series unveils the extraordinary potential of aerogels—a class of highly porous solid materials derived from a gel in which the liquid is replaced by gas while maintaining the self-assembled three-dimensional structure. This video presentation features Dr. Sadhan Jana from University of Akron.
The Aerogel Lecture Series unveils the extraordinary potential of aerogels—a class of highly porous solid materials derived from a gel in which the liquid is replaced by gas while maintaining the self-assembled three-dimensional structure. This video presentation features Dr. Mary Carroll and Dr. Ann Anderson from Union College.
Numerical simulation of compressible multiphase flows based on the four-equation (homogeneous relaxation) model is known to suffer from two fundamental difficulties with (a) wave propagation and (b) pressure equilibrium preservation. First, the mixture sound speed exhibits non-monotonic dependency with respect to the volume fraction, which leads to robustness issues in the resolution of shocks and acoustic wave propagation across two-phase regions. This difficulty can be mitigated by solving Allaire’s five-equation model augmented with infinitely fast phasic temperature equilibrium, from which solutions of the four-equation model can be recovered. However, when temperature is non-uniform, this augmented five-equation formulation still fails to preserve pressure equilibrium across material interfaces. In this work, we propose a fully conservative numerical scheme that exactly preserves pressure equilibrium at the discrete level for the augmented five-equation model, for arbitrary initial distributions of temperature and volume fraction. Combined with the monotonic sound speed property of the five-equation formulation, the proposed pressure-equilibrium preserving scheme significantly improves robustness in the presence of strong multiphase interactions, including shock–interface interactions and advection of material interfaces.
Understanding the spatial heterogeneity beneath Thwaites Glacier, West Antarctica, is vital to projecting its impact on future sea levels. Radar-echo sounding (RES) is commonly used to infer subglacial conditions, but these data can be challenging to interpret. We assess basal heterogeneity across Thwaites Glacier by comparing RES returns to a radar backscattering simulator for over 400 km of RES data. The modeled variations in bed returned power exhibited a strong correlation with actual RES data in 40% of our simulated flight segments, which we consider evidence for a relatively homogeneous glacier bed. Other sites (40%) demonstrated improved fit quality when hydrology or substrate transitions were introduced in the bed material model. The remaining simulated segments (20%) were diagnosed as having more complex basal heterogeneity. The spatial distribution of complex heterogeneity appears to coincide with asymmetric patterns in the RES specularity content, which has been interpreted in previous studies as a signature for channelized hydrology. Conversely, the homogeneous substrate locations coincide with areas of fast-moving ice in western Thwaites. Our simulation method can isolate power variations induced by material heterogeneity vs topography, which is an important limitation of existing RES analysis methods.
With the growing demand for materials capable of withstanding extreme temperatures and pressures, ceramic components with exceptional corrosion resistance and reliable mechanical properties have experienced a significant surge in demand. However, traditional ceramic forming methods involve high-temperatures and energy-intensive processes that often struggle to produce complex parts or composites efficiently. Polymer-Derived Ceramics (PDCs) offer a transformative solution by using polymeric precursors that can be converted into a wide variety of silicon-based and non-silicon-based ceramics through heat treatment. The polymeric nature of PDC precursors enables the fabrication of geometrically intricate components using conventional polymer-forming techniques at significantly lower processing temperatures. Furthermore, PDCs are well-suited for additive manufacturing (AM), allowing the production of complex structural and functional components through cost-effective, low-temperature processes. By leveraging the diverse properties of PDC materials – each with unique advantages and limitations – manufacturers can optimise performance for specific applications. This review provides an overview of the types of PDCs developed to date and their broad range of applications. Specifically, it delves into the Direct Ink Writing (DIW) process, exploring its rheological requirements and the critical role of fillers in tailoring the rheological properties of polymeric precursors to meet the specific demands of DIW.
CdZnTe crystals were grown in one-g and in micro-g for comparative analysis. The two micro-g crystals were grown in the Crystal Growth Furnace during the First United States Microgravity Laboratory mission (USML-1). The samples were analyzed for chemical homogeneity, structural perfection, and optoelectronic performance (infrared transmission). Fourier Transform Infrared (FTIR) transmission of both ground and flight materials showed that the infrared transmission was close to theoretical, 63% versus 66%, suggesting that the material was close to the stochiometric composition during both the ground and flight experiments. Infrared microscopy confirmed that the principal precipitates were Te and their size (1-10 microns) and density suggested that the primary flight and ground base samples experienced similar cooling rates. Macrosegregation was predicted, using scaling analysis, to be low even in one-g crystals and this was confirmed experimentally, with nearly diffusion controlled growth achieved even in the partial mixing regime on the ground. Radial segregation was monitored in the flight samples and was found to vary with fraction solidified, but was disturbed due to the asymmetric grvitational and thermal fields experienced by the flight samples. The flight samples, however, were found to be much higher in structural perfection than the ground samples produced in the same furnace under identical growth conditions except for the gravitational level. Rocking curve widths were found to be substantially reduced, from 20/35 (one-g) to 9/20 (micro-g) for the best regions of the crystals. The full width at half maximum (FWHM) of 9 arc seconds is as good as the best reported terrestrially for this material. The ground samples were found to have a fully developed mosaic structure consisting of subgrains, whereas the flight sample dislocations were discrete and no mosaic substructure was evident. The defect density was reduced from 50-100,000 (one-g) to 500-25000 EPD (micro-g). These results were confirmed using rocking curve analysis, synchrotron topography, and etch pit analysis. The low dislocation density is thought to have resulted from the near-absence of hydrostatic pressure which allowed the melt to solidify with minimum or no wall contact, resulting in very low stress being exerted on the crystal during growth or during post-solidification cooling.