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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 199 records · Page 11

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NASA NTRS1999

Low-Power Temperature-Swing Adsorption for Mars Atmosphere Acquisition

The promise of In-Situ Resource Utilization (ISRU)-based mission architectures for Mars surface exploration will begin to be realized during the next decade as robotic spacecraft sent to Mars carry components and whole chemical plants for producing propellants from the planet's atmosphere. These chemical plants will need to perform three primary operations: acquisition of atmospheric carbon dioxide, reactions to transform the gas into oxygen and possibly fuel, and storage of the products. This presentation focuses on development of technologies at NASA Ames Research Center for the first of these operations, carbon dioxide acquisition.

Finn, J. E.↗

NASA NTRS2015

Sustaining Human Presence on Mars Using ISRU and a Reusable Lander

This paper presents an analysis of the impact of ISRU (In-Site Resource Utilization), reusability, and automation on sustaining a human presence on Mars, requiring a transition from Earth dependence to Earth independence. The study analyzes the surface and transportation architectures and compared campaigns that revealed the importance of ISRU and reusability. A reusable Mars lander, Hercules, eliminates the need to deliver a new descent and ascent stage with each cargo and crew delivery to Mars, reducing the mass delivered from Earth. As part of an evolvable transportation architecture, this investment is key to enabling continuous human presence on Mars. The extensive use of ISRU reduces the logistics supply chain from Earth in order to support population growth at Mars. Reliable and autonomous systems, in conjunction with robotics, are required to enable ISRU architectures as systems must operate and maintain themselves while the crew is not present. A comparison of Mars campaigns is presented to show the impact of adding these investments and their ability to contribute to sustaining a human presence on Mars.

Arney, Dale C.↗

NASA NTRS2017

DART: Recent Advances in Remote Sensing Data Modeling With Atmosphere, Polarization, and Chlorophyll Fluorescence

To better understand the life-essential cycles and processes of our planet and to further develop remote sensing (RS) technology, there is an increasing need for models that simulate the radiative budget (RB) and RS acquisitions of urban and natural landscapes using physical approaches and considering the three-dimensional (3-D) architecture of Earth surfaces. Discrete anisotropic radiative transfer (DART) is one of the most comprehensive physically based 3-D models of Earth-atmosphere radiative transfer, covering the spectral domain from ultraviolet to thermal infrared wavelengths. It simulates the optical 3-DRB and optical signals of proximal, aerial, and satellite imaging spectrometers and laser scanners, for any urban and/or natural landscapes and for any experimental and instrumental configurations. It is freely available for research and teaching activities. In this paper, we briefly introduce DART theory and present recent advances in simulated sensors (LiDAR and cameras with finite field of view) and modeling mechanisms (atmosphere, specular reflectance with polarization and chlorophyll fluorescence). A case study demonstrating a novel application of DART to investigate urban landscapes is also presented.

Gastellu-Etchegorry, Jean-Phil↗

NASA NTRS2018

TPSAS-NF1676L-31282-DND

Several technology investments, beyond those used for robotic missions, are required to develop Mars human scale Entry, Descent, and Landing (EDL) systems. In a resource-constrained environment, studies play the critical role of identifying the most feasible technical paths and high payoff investments. One such NASA multi-directorate, multi-center study, is called the Entry, Descent and Landing Architecture Study (EDLAS). This paper presents a summary of phase two of the study conducted from October 2016 to September 2017. Study ground rules and assumptions are provided by NASA?s Human Exploration and Operations Mission Directorate (HEOMD) and include a Mars architecture and Mars surface lander payload manifests. Four unique entry technologies with the potential to deliver a specified 20 t human scale payload to the Mars surface are considered for analysis. Two of these techniques are evolutionary rigid vehicles, derived from robotic capsule missions and the space shuttle. Likewise, two revolutionary deployable vehicles are considered, the Adaptable Deployable Entry Placement Technology (ADEPT) and Hypersonic Inflatable Aerodynamic Decelerator (HIAD). This paper summarizes updates to the entry technology designs, the analysis motivation and approach, figures of merit by which the configurations are compared, and results of the analyses. Finally, findings are presented with the recommendation that two of the four configurations, one evolutionary and one revolutionary technology, continue to be studied in future human scale EDL studies.

Alicia Dwyer Cianciolo↗

NASA NTRSDate not supplied

Segmented Hexagonal Antenna Reflector Concentrically Stacked Using Shape Memory Composite Tubular Hinges

A new architecture for solid surface reflector antennas scalable to sizes greater than 10 m is presented. The design combines the compact, lightness and simplicity characteristics of advanced deployable structures to create sub-reflectors that can be assembled in space into larger units using a robotic arm and operations under development by a related parallel project. The seven-panel hexagonal sub-reflector is divided into hexagonal panels of that efficiently stack concentrically and vertically. The central panel is connected to each side panel on the back side by a pair of tubular shape memory composite hinges that enable the required deployment kinematics. A secondary mechanism ultimately closes the interpanel gap. The focus of the paper is on the development of the sub-reflector elements, namely the tubular hinges that use embedded heaters and sensors for actuation, the actuation mechanisms, and the lightweight sandwich construction panels. A finite element analysis parametric study assessed how design features of the hinge affect its stowage and deployment dynamics. The component fabrication and testing plans for the two-panel assembly breadboard model are outlined.

deployable reflectors↗

NASA NTRSDate not supplied

Segmented Hexagonal Antenna Reflector Concentrically Stacked Using Shape Memory Composite Tubular Hinges

deployable reflectors↗

NASA NTRSDate not supplied

Segmented Hexagonal Antenna Reflector Concentrically Stacked Using Shape Memory Composite Tubular Hinges

A new architecture for solid surface reflector antennas scalable to sizes greater than 10 m is presented. The design uses compact, light, and simple advanced deployable structures to create sub-reflectors that can be assembled in space into larger units using a robotic arm. The seven-panel hexagonal sub-reflector is divided into hexagonal panels that stack concentrically and vertically. The central panel is connected to each side panel on the back side by a pair of tubular shape memory composite hinges that enable the required deployment kinematics with controlled dynamics. A secondary mechanism closes the interpanel gap. The focus of the paper is on the development of the sub-reflector elements, namely the tubular hinges that use embedded heaters and sensors for triggering and control, the actuation mechanisms, and the lightweight sandwich construction reflector panels. A parametric study using finite element analyses was conducted to assess how design features of the hinge affect its stowage and deployment dynamics. The preliminary component fabrication and testing results for the two-panel assembly breadboard model are outlined. Finally, the results of the test campaign with the brassboard reflector model are presented. A comparison of deployed reflector surface deviation between the measured surface after the stowage and deployment process and the pre-test scans and the nominal surface revealed root mean square errors of less than 1 mm, as required by X-band radiofrequency transmission.

gravity offloading methods↗

NASA NTRS2024

Framework for Seismic Vulnerability Assessment of Nonstructural Elements Inside an Inflatable Lunar Habitat

The pursuit of knowledge and curiosity are once again driving humanity to seek a human presence on extraterrestrial bodies. While numerous challenges must be overcome on the moon to achieve this goal, the moonquake hazard has often been overlooked. Using NASA’s Moon to Mars Architecture requirements for surface habitation and accounting for the midterm/long-term mission duration, a framework for vulnerability assessment is developed for essential nonstructural elements (NSEs) inside an inflatable habitat subjected to moonquakes. The aim of this study is to develop an approach to assess the vulnerability of typical NSEs that support essential equipment, such as the environmental control and life support system, under a paucity of information related to the seismic hazard. We also emphasize that the launch dynamic environment and lunar seismic environment exhibit notable differences in their characteristics, which can lead to higher lateral acceleration levels than initially expected. This acceleration may be linked to high-occurrence seismic events. However, due to the lack of information regarding the frequency of these events, the risk of NSEs being subjected to unforeseen loads increases. It is imperative to equip future lunar habitats with seismic mitigation measures until additional seismometers are deployed near upcoming surface human outposts.

Oscar D Forero↗

DOE OSTI2017

A Cable Car Transfer System for the Cigeo Access Ramps - An Original Approach - 17035

Andra is currently implementing the detailed engineering phase of the step-wise design of Cigeo (the French HLW and IL-LLW Deep Geological Repository). Various technical issues are at stake, including the definition and development of a key component: a funicular ('cable-car') system dedicated to the transfer (down the access ramp and leading to the underground infrastructures) of the shielding casks housing the waste disposal containers (packages). The present paper starts with a brief description of the Cigeo architecture (i.e. the surface utilities, the service and nuclear ramps, the various shafts and finally the underground facilities). A focus is then made on the 'nuclear ramp' dedicated to the transfer of the waste containers lodged inside the casks (those latter weighing some 100 to 130 metric tons each) and its main geometrical characteristics (slope, length, diameter, structure). Then a discussion follows to detail the rationale having led to the choice of a somehow 'sophisticated' funicular transfer system, at the expense of what could be called 'more conventional' and more straightforward transport solutions (like a transfer system by trucks or by rack and pinion trains). A systematic comparison is finally made between the various solutions, explaining and rating the pros and cons of each concept, via a multi-criteria analysis. This technical choice (and the related justification approach) was submitted to an Experts review at the end of the Preliminary Design phase of Cigeo and comforted by their strong support before the design freeze of this solution was integrated in Cigeo. The following part of the paper is then focused on a description of the main technical components and the mechanical performance of the cable-car system, its current state of design and the set of qualification tests (of key safety components) to be implemented before its effective construction. This article concludes with a timeline of the qualification tests and developments to come. The positive outcomes of this future technical test campaign will also pave the way for the future instruction of the Cigeo licensing file, scheduled as of mid-2018. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2024

Additive Manufacturing of Thermal Energy Storage Composites with Microencapsulated Phase Change Materials Supported in a Multi-Polymer Matrix

Advanced manufacturing techniques, such as additive manufacturing (AM), that can directly integrate phase change materials (PCMs) have garnered interest in recent years due to their potential for development of highly efficient thermal energy storage architectures. Complex, high surface area geometries embedded with PCMs that are only feasible with AM can improve thermal management with reduced material waste. Our work focuses on developing composite filaments with microencapsulated phase change materials (MEPCM) bound within a single or dual polymer matrix that can be processed through standard filament extruders and additively manufactured using off-the-shelf 3D printers. Polymer powders, rather than polymer pellets, were key to homogenously mixed filaments achieving high MEPCM loadings with no deterioration in thermal energy storage (TES) capability during extrusion. Composite filaments contain upwards of 60 wt% MEPCM and were printed without loss in feature resolution, print speed, or layer adhesion. Storage enthalpies of printed composites range from 100 - 130 kJ/kg, which were within 5% of the theoretical enthalpy based on weight fraction of MEPCM and maintained enthalpies within 1% over 500 thermal cycles. We can reliably manufacture low density, high surface area structures like 15% gyroid infill, along with dense, compact pucks at a 100% concentric infill. Prints were also scalable to a 900 cm3 honeycomb infill heat exchanger model that has an estimated energy storage capacity of 9 Wh.

3D printing↗

NASA NTRS2023

Science Objectives for Human Exploration of Mars Workshop Report

The Science Objectives for Human Exploration of Mars Workshop was held in Denver, Colorado on May 4–6, 2022. The workshop was co-sponsored by NASA’s Science Mission Directorate and the Exploration Systems Development Mission Directorate to actively engage the planetary science community to determine what planetary science should be done by human crews on the martian surface and how those science objectives can be achieved. Sessions at the Science Objectives for Human Exploration of Mars Workshop were organized around specific planetary science objectives and mission architecture concepts that were identified during the workshop as the highest priority for human exploration. The intent of this workshop was to synthesize a notional, integrated concept of operations for each scenario to aid in planning and refining the mission architecture for the first human mission to Mars. Results from the Planetary Decadal Survey Report were released xx days before the workshop and were briefed to workshop participants who incorporated the findings in the discussions. With the Artemis missions, humans will return to the Moon using innovative technologies to explore the lunar surface. We will apply what we learn about exploration architecture, surface infrastructure, and science and exploration operations on and around the Moon to conduct successful missions with the first astronauts to Mars. A human mission to Mars will be a landmark achievement and a golden opportunity to make groundbreaking scientific discoveries on Mars. The potential scope of the science activities and impact of achieving those objectives are extraordinary.

Mars↗

DOE OSTI2017

Control of Architecture in Rhombic Dodecahedral Pt–Ni Nanoframe Electrocatalysts

Platinum-based alloys are known to demonstrate advanced properties in electrochemical reactions that are relevant for proton exchange membrane fuel cells and electrolyzers. Further development of Pt alloy electrocatalysts relies on the design of architectures with highly active surfaces and optimized utilization of the expensive element, Pt. For this study, we show that the three-dimensional Pt anisotropy of Pt-Ni rhombic dodecahedra can be tuned by controlling the ratio between Pt and Ni precursors such that either a completely hollow nanoframe or a new architecture, the excavated nanoframe, can be obtained. The excavated nanoframe showed ~10 times higher specific and ~6 times higher mass activity for the oxygen reduction reaction than Pt/C, and twice the mass activity of the hollow nanoframe. The high activity is attributed to enhanced Ni content in the near-surface region and the extended two-dimensional sheet structure within the nanoframe that minimizes the number of buried Pt sites.

36 MATERIALS SCIENCE↗

NASA NTRS2010

A Dual Launch Robotic and Human Lunar Mission Architecture

This paper describes a comprehensive lunar exploration architecture developed by Marshall Space Flight Center's Advanced Concepts Office that features a science-based surface exploration strategy and a transportation architecture that uses two launches of a heavy lift launch vehicle to deliver human and robotic mission systems to the moon. The principal advantage of the dual launch lunar mission strategy is the reduced cost and risk resulting from the development of just one launch vehicle system. The dual launch lunar mission architecture may also enhance opportunities for commercial and international partnerships by using expendable launch vehicle services for robotic missions or development of surface exploration elements. Furthermore, this architecture is particularly suited to the integration of robotic and human exploration to maximize science return. For surface operations, an innovative dual-mode rover is presented that is capable of performing robotic science exploration as well as transporting human crew conducting surface exploration. The dual-mode rover can be deployed to the lunar surface to perform precursor science activities, collect samples, scout potential crew landing sites, and meet the crew at a designated landing site. With this approach, the crew is able to evaluate the robotically collected samples to select the best samples for return to Earth to maximize the scientific value. The rovers can continue robotic exploration after the crew leaves the lunar surface. The transportation system for the dual launch mission architecture uses a lunar-orbit-rendezvous strategy. Two heavy lift launch vehicles depart from Earth within a six hour period to transport the lunar lander and crew elements separately to lunar orbit. In lunar orbit, the crew transfer vehicle docks with the lander and the crew boards the lander for descent to the surface. After the surface mission, the crew returns to the orbiting transfer vehicle for the return to the Earth. This paper describes a complete transportation architecture including the analysis of transportation element options and sensitivities including: transportation element mass to surface landed mass; lander propellant options; and mission crew size. Based on this analysis, initial design concepts for the launch vehicle, crew module and lunar lander are presented. The paper also describes how the dual launch lunar mission architecture would fit into a more general overarching human space exploration philosophy that would allow expanded application of mission transportation elements for missions beyond the Earth-moon realm.

Jones, David L.↗

DOE OSTI2015

Tunable Affinity and Molecular Architecture Lead to Diverse Self-Assembled Supramolecular Structures in Thin Films

The self-assembly behaviors of specifically designed giant surfactants are systematically studied in thin films using grazing incident X-ray and transmission electron microscopy (TEM), focusing on the effects of head surface functionalities and molecular architectures on nanostructure formation. Two molecular nanoparticles (MNPs) with different affinities, i.e., hydrophilic carboxylic acid functionalized [60]fullerene (AC60) and omniphobic fluorinated polyhedral oligomeric silsesquioxane (FPOSS), are utilized as heads of the giant surfactants. By covalently tethering these functional MNPs onto the chain end or the junction point of polystyrene-block-poly(ethylene oxide) (PS-b-PEO) diblock copolymer, linear and star-like giant surfactants possess distinct molecular architectures are constructed. With fixed length of the PEO block, the molecular weight change of the PS block originates the phase formation and transition. Due to the distinct affinity, the AC60-based giant surfactants form two-component morphologies, while three-component morphologies are found in the FPOSS-based ones. A PS block stretching parameter is introduced to characterize the PS chain conformation in different morphologies. The highly diverse self-assembly behaviors and the tunable dimensions in thin films suggest the giant surfactants could be a promising and robust platform for nanolithography applications.

molecular architecture↗

NASA NTRSDate not supplied

Sizing, Buckling, and Thermal-Structural Analysis of Tall Lunar Tower

Tall lunar towers enable direct collection of solar energy using solar panels that can generate power exceeding 100-kW above shadowed regions on the surface. Tall lunar towers also support solar reflectors and concentrators for solar farms, which enable various mission architectures on the lunar surface. The Tall Lunar Tower (TLT) project at NASA Langley Research Center is focused on the design, modeling, fabrication, and testing of an assembled TLT Engineering Development Unit (EDU). In this paper, the design and analysis plan of a TLT is presented and predicted buckling and thermal-structural response of the TLT EDU on the lunar surface are investigated.

Kyongchan Song↗

NASA NTRSDate not supplied

Sizing, Buckling, and Thermal-Structural Analysis of Tall Lunar Tower

Kyongchan Song↗

DOE OSTI2019

Surface Chemistry, Passivation, and Electrode Performance in Core–Shell Architectures of LiCoO 2 Nanoplates

Core–shell structures offer opportunities to overcome challenges to the durability of Li-ion batteries with high energy density due to instability at the cathode/electrolyte interface. Achieving complete stability requires fundamental understanding of the role of the shell in providing passivation without compromising carrier transport, by tuning surface chemistry and structural features in a highly conformal barrier layer. Here, individual LiCoO 2 nanoplates were employed as the core, and passivating shells were grown at a tailored thickness and composition, through different Al loadings and annealing temperatures. Depending on the annealing conditions, the sub-5 nm shells were shown to vary from amorphous aluminum oxide layers to LiAl x Co 1–x O 2 gradients, resulting in an Al-rich outer layer on a Co-rich core. This control revealed the differing balance between effective minimization of redox-active Co 3+ at the surface and transport properties of the two types of shell. Based on correlations with electrode performance, the requirements in thickness of the layers were proposed to critically depend on their chemical composition, with epitaxial shells based on surface substitution being favored. As a result, the outcomes of the study simultaneously advance the ability to assemble complex oxides into heterostructures and refine the rules of design for tunable passivation through a barrier layer, so as to maximize electrode properties in practical batteries.

25 ENERGY STORAGE↗

DOE OSTI2018

Nucleation and Crystal Growth in the Formation of Hierarchical Three-Dimensional Nanoarchitecture

This project is to obtain fundamental understandings of the operation of the Ostwald-Lussac (OL) Law and the oriented attachment (OA) mechanism in nucleation and growth of TiO2 nanorods (NR) via surface-reaction-limited pulsed chemical vapor deposition (SPCVD) process. Three-dimensional (3D) NW networks are a unique type of mesoporous architecture that offers extraordinary surface area density and superior transport properties of electrons, photons, and phonons. It is exceptionally promising for advancing the design and application of functional materials for photovoltaic devices, catalysts beds, hydrogen storage systems, sensors, and battery electrodes. Our group has developed the SPCVD technique by mimicking the mechanism of atomic layer deposition (ALD), which effectively decoupled the crystal growth from precursor concentration while retaining anisotropic 1D growth. For the first time, this technique realized a 3D NW architecture with ultrahigh density and achieved ~4-5 times enhancement on photo-conversion efficiency. Through the support of our current DOE award, we revealed the governing role of the OL Law in the nucleation stage of SPCVD. The formation of NR morphology in SPCVD was identified following the OA mechanism. We also discovered a unique vapor-phase Kirkendall effect in the evolution of tubular or core-shell NR structures. These understandings opened many new opportunities in designing 3D NW architectures with improved properties or new functionalities. Specifically, our accomplishments from this project include five aspects: (1) Observation of the Ostwald-Lussac Law in high-temperature ALD. (2) Observation of vapor-solid Kirkendall effect in ZnO-to-TiO2 nanostructure conversion. (3) Development of highly-efficient capillary photoelectrochemical (PEC) solar-fuel generation. (4) Development of efficient and stable electrochemical protections for black silicon PEC electrodes. (5) Development of doped polymers with tunable electrical properties. This project brings a new level of transformative knowledge on nucleation and crystal growth in the SPCVD NR growth processes. Specifically, quantification of the activation energy landscape guided by the OL law will allow us to establish a critical knowledge base of nucleation kinetics for SPCVD synthesis of NR branches on different material surfaces. Studying the OA kinetics will establish a transformative knowledge base to support this new crystal growth mechanism that can be applied to many functional material systems. This research will pave the road toward a capable and versatile synthesis technology for creating 3D hierarchical mesoscale structures.

36 MATERIALS SCIENCE↗