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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 631 records · Page 35
All sourcesNASA NTRSDOE OSTI
NASA NTRS1989

Molecular weight characterization of advanced thermoplastic resins

Analytical techniques including low angle laser light scattering photometry (LALLS), differential viscometry (DV), gel permeation chromatography (GPC), GPC-LALLS and GPC-DV, were used to characterize the molecular weight and molecular weight distribution of several advanced thermoplastics. A discussion is presented of various molecular-weight-related parameters obtained by these techniques on an experimental polyimide and poly(arylene ether ketone) and a commercially available polysulfone. Where possible, these parameters are correlated with processability and selected mechanical properties. The molecular weight was found to vary during the thermal conversion of poly(amic acid) to polyimide. However, no change in composition of the polysulfone was noted in response to various processing procedures.

Young, Philip R.↗
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.↗
DOE OSTI2023

Sustainable chemistry with plasmonic photocatalysts

There is a pressing global need to increase the use of renewable energy sources and limit greenhouse gas emissions. Towards this goal, highly efficient and molecularly selective chemical processes that operate under mild conditions are critical. Plasmonic photocatalysis uses optically resonant metallic nanoparticles and their resulting plasmonic, electronic, and phononic light-matter interactions to drive chemical reactions. The promise of simultaneous high-efficiency and product-selective reactions with plasmon photocatalysis provides a compelling opportunity to rethink how chemistry is achieved. Plasmonic nanoparticles serve as nanoscale ‘antennas’ that enable strong light–matter interactions, surpassing the light-harvesting capabilities one would expect purely from their size. Complex composite structures, combining engineered light harvesters with more chemically active components, are a focal point of current research endeavors. In this review, we provide an overview of recent advances in plasmonic catalysis. We start with a discussion of the relevant mechanisms in photochemical transformations and explain hot-carrier generation and distributions from several ubiquitous plasmonic antennae. Then we highlight three important types of catalytic processes for sustainable chemistry: ammonia synthesis, hydrogen production and CO 2 reduction. To help elucidate the reaction mechanism, both state-of-art electromagnetic calculations and quantum mechanistic calculations are discussed. This review provides insights to better understand the mechanism of plasmonic photocatalysis with a variety of metallic and composite nanostructures toward designing and controlling improved platforms for green chemistry in the future.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Design and Testing of the Address in Real-Time Data Driver Card for the Micromegas Detector of the ATLAS New Small Wheel Upgrade

The Address in Real Time Data Driver Card (ADDC) is designed to transmit the trigger data in the Micro-Mesh Gaseous Structure (Micromegas) detector of the ATLAS New Small Wheel (NSW) upgrade. The Address in Real Time (ART) signals are generated by the front-end ASIC, named VMM chip, to indicate the address of the first above-threshold event. A custom ASIC (ART ASIC) is designed to receive the ART signals from the VMM chip and implement the hit-selection. The processed data from the ART ASIC will be transmitted out of the NSW through the GBTx serializer, the unidirectional Versatile Twin Transmitter (VTTx) and fiber optical links. The ART signal is critical for the ATLAS experiment trigger selection thus the performance and stability of the ADDC is very important. To ensure extensive testing of the ADDC, an FPGA Mezzanine Card (FMC) based testing platform and a special designed firmware/software are developed. We find that this test platform works with the commercial Xilinx VC707 FPGA development kit, independent of the other electronics of the NSW it can test all the functions of the ADDC and its long-term stability. This paper will introduce the design, testing procedure and results of the ADDC and the FMC testing platform.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

Molten Salt vs. Liquid Sodium Receiver Selection Using the Analytic Hierarchy Process

An international team led by NREL analyzed the favorability of two alternative liquid receiver designs for a 700+ degrees C receiver under the Gen3 CSP Liquid Pathway project. The competing liquid heat transfer fluids were a ternary chloride salt and liquid-metal sodium. The team applied a facilitated analytic hierarchy process (AHP) to arrive at a recommended alternative and set a path forward for the project. The AHP criteria were formulated, weighted, and scored by the project leadership team and technical advisory committee consisting of energy industry and CSP experts. The six- month process culminated with a two-day workshop where the sodium alternative was deemed to have both a significantly higher benefit (19.3%) and a lower LCOE (11.4%), with only a slightly higher risk (~3%) than the salt alternative. Consequently, a sodium-receiver design was selected for the Liquid Pathway project, where it will be used to charge a two- tank chloride salt thermal energy storage system.

analytic hierarchy process↗
DOE OSTI2020

Reduction of CO 2 Emissions Through Lightweight Body Panels (Project Final Report)

Lightweight construction is an integral part of Volkswagen’s overall strategy of reducing CO 2 emissions. Due to its low cost, steel is the most commonly used material for automotive exterior body panels today. Unfortunately, steel has a high density, resulting in a relatively low specific strength. Glass fiber based sheet molding compounds (SMC) provide high properties in combination with lower density. The high specific strength of SMC offers an enormous lightweight potential. To unlock the full potential of SMC materials in combination with cutting edge manufacturing processes, Volkswagen Group of America worked together with IACMI (Institute for Advanced Composites Manufacturing Innovation) and the academic partners: University of Tennessee Knoxville, Purdue University and Michigan State University; as well as the industry partners: Ashland, IDI, Owens Corning and Continental Structural Plastics. Leveraging the expertise of all project partners, reaching over the entire supply chain the project demonstrated the potential of these materials. This report will highlight the major steps in the development process on the way to technology readiness for SMC using the example of the Volkswagen Atlas Liftgate. Over the 36-month period of the project, the work focused on three R&D areas: material development, design and simulation, and development of the manufacturing process. Material selection included alternative fibers and resin systems, and accounted for material availability, properties, and cost-efficiency. The work undertaken in the field of design and simulation has pushed the envelope of short fiber reinforced thermoset molding compound process simulation. Design iterations were virtually tested, while the final design was used to validate the simulation software against physical parts. Manufacturing development used cutting-edge technology, while experts along the supply chain were working together to ensure the best possible results. In the final stage of the project, liftgates were molded, trimmed, bonded, painted and assembled before exhaustive testing. The result is an e-coat (electrophoretic dip coating) capable Class-A SMC liftgate, which is ready for high-volume production, and can be used as a technology demonstrator. The prototypes manufactured in the scope of this work have exhibited a mass reduction for the Volkswagen Atlas liftgate of up to 35% compared to the series production steel version, without a degradation of the functionalities.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Machine Learning-Driven Optimization of Building Enclosures for Moisture Durability and Thermal Performance

The design of moisture-durable building enclosures with low embodied carbon often involves an iterative process of selecting the materials for the specific exposure conditions to meet the performance requirements. While hygrothermal simulations are commonly used to evaluate moisture durability, they often require advanced expertise for proper implementation. Machine learning (ML) provides a promising alternative by streamlining the design process and minimizing the reliance on complex simulations. This study presents a machine learning-based approach for predicting moisture durability in residential wall assemblies. The ML model was trained to estimate the mold index and maximum moisture content of various layers under typical exposure conditions. The model achieved a high predictive accuracy, with a coefficient of determination (R²) exceeding 0.90 when compared to traditional hygrothermal simulations on materials that were not part of training the ML model. Building on these results, the ML model was developed into a practical tool for optimizing wall assembly designs. This tool allows users to automatically optimize material selections based on energy, moisture, and carbon performance criteria. By incorporating multi-objective optimization, the tool identifies configurations that minimize embodied carbon while maintaining moisture safety and code-compliant thermal performance. Additionally, it provides insights into how material choices influence assembly durability, energy efficiency, and carbon reduction. The tool will be implemented in the Building Science Advisor (BSA) to enhance its performance and provide more granularity on the results. This research highlights the potential for ML-driven tools to simplify the design of high-performance building enclosures, offering architects and engineers a faster, more efficient way to balance critical performance factors.

Salonvaara, Mikael [ORNL] (ORCID:0000000318991554)↗
DOE OSTI2021

Molten Salt vs. Liquid Sodium Receiver Selection Using the Analytic Hierarchy Process: Preprint

An international team led by NREL analyzed the favorability of two alternative liquid receiver designs for a 700+ °C receiver under the Gen3 CSP Liquid Pathway project. The competing liquid heat transfer fluids were a ternary chloride salt and liquid-metal sodium. The team applied a facilitated analytic hierarchy process (AHP) to arrive at a recommended alternative and set a path forward for the project. The AHP criteria were formulated, weighted, and scored by the project leadership team and technical advisory committee consisting of energy industry and CSP experts. The six-month process culminated with a two-day workshop where the sodium alternative was deemed to have both a significantly higher benefit (19.3%) and a lower LCOE (11.4%), with only a slightly higher risk (~3%) than the salt alternative. Consequently, a sodium-receiver design was selected for the Liquid Pathway project, where it will be used to charge a two-tank chloride salt thermal energy storage system.

41 EE - Solar Energy Technologies Office (EE-4S)↗
DOE OSTI2023

Adaptive cache management based on programming model information

A processing system selectively allocates space to store a group of one or more cache lines at a cache level of a cache hierarchy having a plurality of cache levels based on memory access patterns of a software application executing at the processing system. The processing system generates bit vectors indicating which cache levels are to allocate space to store groups of one or more cache lines based on the memory access patterns, which are derived from data granularity and movement information. Based on the bit vectors, the processing system provides hints to the cache hierarchy indicating the lowest cache level that can exploit the reuse potential for a particular data.

Na, Weon Taek↗
DOE OSTI2024

Understanding Process–Structure Relationships during Lamination of Halide Perovskite Interfaces

Fabrication of halide perovskite (HP) solar cells typically involves the sequential deposition of multiple layers to create a device stack, which is limited by the thermal and chemical incompatibility of top contact layers with the underlying HP semiconductor. One emerging strategy to overcome these restrictions on material selection and processing conditions is lamination, where two half-stacks are independently processed and then diffusion bonded to complete the device. Lamination reduces the processing constraints on the top side of the solar cell to allow new device designs, expanded use of deposition methods, and self-encapsulation of devices. While laminated perovskite solar cells with high efficiencies and novel interlayer combinations have been demonstrated, there is a limited understanding of how the lamination process parameters affect the diffusion-bond quality and material properties of the resulting HP layer. In this study, we systematically vary temperature, pressure, and time during lamination and quantify the resulting impacts on bonded area, grain domain size, and photoluminescence. A design of experiments is performed, and statistical analysis of the experimental results is used to quantitatively evaluate the resulting process–structure–property relationships. The lamination temperature is found to be the key parameter controlling these properties. Furthermore, a temperature of 150 °C enables successful bonding over 95% of the substrate area and also results in increases in apparent grain domain size and photoluminescence intensity. Based on these insights, the lamination temperature of functional perovskite solar cell devices is varied, demonstrating the importance of the resulting bond quality on device performance metrics.

14 SOLAR ENERGY↗
NASA NTRS2007

ISRU System Model Tool: From Excavation to Oxygen Production

In the late 80's, conceptual designs for an in situ oxygen production plant were documented in a study by Eagle Engineering [1]. In the "Summary of Findings" of this study, it is clearly pointed out that: "reported process mass and power estimates lack a consistent basis to allow comparison." The study goes on to say: "A study to produce a set of process mass, power, and volume requirements on a consistent basis is recommended." Today, approximately twenty years later, as humans plan to return to the moon and venture beyond, the need for flexible up-to-date models of the oxygen extraction production process has become even more clear. Multiple processes for the production of oxygen from lunar regolith are being investigated by NASA, academia, and industry. Three processes that have shown technical merit are molten regolith electrolysis, hydrogen reduction, and carbothermal reduction. These processes have been selected by NASA as the basis for the development of the ISRU System Model Tool (ISMT). In working to develop up-to-date system models for these processes NASA hopes to accomplish the following: (1) help in the evaluation process to select the most cost-effective and efficient process for further prototype development, (2) identify key parameters, (3) optimize the excavation and oxygen production processes, and (4) provide estimates on energy and power requirements, mass and volume of the system, oxygen production rate, mass of regolith required, mass of consumables, and other important parameters. Also, as confidence and high fidelity is achieved with each component's model, new techniques and processes can be introduced and analyzed at a fraction of the cost of traditional hardware development and test approaches. A first generation ISRU System Model Tool has been used to provide inputs to the Lunar Architecture Team studies.

Santiago-Maldonado, Edgardo↗
NASA NTRSDate not supplied

Selecting Approaches for Enabling Enterprise Data Search: NASA’s Science Mission Directorate (SMD) Catalog

NASA’s Science Mission Directorate (SMD) is working to build an open-source science infrastructure to accelerate open, collaborative and interdisciplinary science. One key component in the open-source science infrastructure is the SMD data catalog. In this paper, we present our process for selecting a technical approach to building a NASA SMD enterprise-wide integrated search capability for science users across multiple science disciplines to support discovery and access to complex scientific data.

Kaylin Bugbee↗
NASA NTRS1992

Space Station Furnace Facility Core. Requirements definition and conceptual design study. Volume 2: Technical report. Appendix 6: Technical summary reports

The Space Station Furnace Facility (SSFF) is a modular facility for materials research in the microgravity environment of the Space Station Freedom (SSF). The SSFF is designed for crystal growth and solidification research in the fields of electronic and photonic materials, metals and alloys, and glasses and ceramics and will allow for experimental determination of the role of gravitational forces in the solidification process. The facility will provide a capability for basic scientific research and will evaluate the commercial viability of low-gravity processing of selected technologically important materials. The facility is designed to support a complement of furnace modules as outlined in the Science Capabilities Requirements Document (SCRD). The SSFF is a three rack facility that provides the functions, interfaces, and equipment necessary for the processing of the furnaces and consists of two main parts: the SSFF Core Rack and the two Experiment Racks. The facility is designed to accommodate two experimenter-provided furnace modules housed within the two experiment racks, and is designed to operate these two furnace modules simultaneously. The SCRD specifies a wide range of furnace requirements and serves as the basis for the SSFF conceptual design. SSFF will support automated processing during the man-tended operations and is also designed for crew interface during the permanently manned configuration. The facility is modular in design and facilitates changes as required, so the SSFF is adept to modifications, maintenance, reconfiguration, and technology evolution.

Source record↗
NASA NTRS1973

Study for identification of Beneficial Uses of Space (BUS). Volume 2: Technical report. Book 1: Sections 1 through 4

Consolidated information is presented for the study whose purpose was to identify products, processes, and services to be produced in future spacecraft environments for direct utilization on earth. Discussion of methodology for selecting from among potential space processing approaches, definition of requirements for experiments and tests needed to acquire sufficient knowledge for proof testing of selected processes, formulation of research and development schedules to achieve proof testing, and documentation of the decision processes involved in the programs are presented. Technology and programmatics are reported for the following select studies: (1) surface acoustic wave components; (2) transparent oxides; (3) high purity tungsten X-ray targets; and (4) high specificity isoenzymes.

Source record↗
NASA NTRS2001

Guidelines for the Selection of Near-Earth Thermal Environment Parameters for Spacecraft Design

Thermal analysis and design of Earth orbiting systems requires specification of three environmental thermal parameters: the direct solar irradiance, Earth's local albedo, and outgoing longwave radiance (OLR). In the early 1990s data sets from the Earth Radiation Budget Experiment were analyzed on behalf of the Space Station Program to provide an accurate description of these parameters as a function of averaging time along the orbital path. This information, documented in SSP 30425 and, in more generic form in NASA/TM-4527, enabled the specification of the proper thermal parameters for systems of various thermal response time constants. However, working with the engineering community and SSP-30425 and TM-4527 products over a number of years revealed difficulties in interpretation and application of this material. For this reason it was decided to develop this guidelines document to help resolve these issues of practical application. In the process, the data were extensively reprocessed and a new computer code, the Simple Thermal Environment Model (STEM) was developed to simplify the process of selecting the parameters for input into extreme hot and cold thermal analyses and design specifications. In the process, greatly improved values for the cold case OLR values for high inclination orbits were derived. Thermal parameters for satellites in low, medium, and high inclination low-Earth orbit and with various system thermal time constraints are recommended for analysis of extreme hot and cold conditions. Practical information as to the interpretation and application of the information and an introduction to the STEM are included. Complete documentation for STEM is found in the user's manual, in preparation.

Anderson, B. J.↗
NASA NTRS1974

Space shuttle/food system study. Volume 2, Appendix A: Active heating system-screening analysis. Appendix B: Reconstituted food heating techniques analysis

Technical data are presented which were used to evaluate active heating methods to be incorporated into the space shuttle food system design, and also to evaluate the relative merits and penalties associated with various approaches to the heating of rehydrated food during space flight. Equipment heating candidates were subject to a preliminary screening performed by a selection rationale process which considered the following parameters; (1) gravitational effect; (2) safety; (3) operability; (4) system compatibility; (5) serviceability; (6) crew acceptability; (7) crew time; (8) development risk; and (9) operating cost. A hot air oven, electrically heated food tray, and microwave oven were selected for further consideration and analysis. Passive, semi-active, and active food preparation approaches were also studied in an effort to determine the optimum method for heating rehydrated food. Potential complexity, cost, vehicle impact penalties, and palatability were considered in the analysis. A summary of the study results is provided along with cost estimates for each of the potential sytems

Source record↗
NASA NTRS2015

Organics in Space: Results from Space Exposure Platforms and Nanosatellites

A series of successful laboratory astrophysics experiments performed on International Space Station(ISS) external platforms such as EXPOSE have provided insights into the evolution of organic and biological materials in space and planetary environments. The study of the reactions, destruction, and longevity of organics in the space environment is of fundamental interest. To provide an accurate outer space environment for extended durations, exposure experiments in low Earth orbit have been conducted in the last decades in order to examine the consequences of actual space conditions including combinations of solar and cosmic radiation, space vacuum, and microgravity. The OOREOS (OrganismORganic Exposure to Orbital Stresses) nanosatellite studied in situ during the 6-month primary and 1-year extended mission the photochemical processing of selected PAHs in low Earth orbit (650 km altitude); results were autonomously telemetered to Earth. We report on the methods and flight preparation of samples for space exposure platforms and results on the stability of organic thin-films. The UV-vis degradation process of thin-films was recorded over time, which revealed intriguing and counter-intuitive photolytic kinetics that will be re-investigated on the ISS in a space environment.

Space weathering↗
DOE OSTI2025

Treatment of antibiotic-manufacturing wastewater enriches for Aeromonas veronii, a zoonotic antibiotic-resistant emerging pathogen

Antibiotic-manufacturing wastewater treatment plants primarily target chemical pollutants, but their processes may select for antibiotic-resistant pathogens and antibiotic resistance genes. Leveraging the combined strengths of deep metagenomic sequencing, 16S rRNA gene sequencing, quantitative polymerase chain reaction, and bacterial culturing, we investigated bacterial communities and antibiotic resistomes across eleven treatment units in a full-scale antibiotic-manufacturing wastewater treatment plant processing wastewater from a β-lactam manufacturing facility. Both bacterial communities and antibiotic resistance gene compositions varied across the treatment units, but were associated. Certain antibiotic resistance gene persisted through treatment, either carried by identical bacterial species, or linked to mobile genetic elements in different species. Despite the satisfactory performance in chemical removal, this plant continuously enriched zoonotic antibiotic-resistant Aeromonas veronii (an emerging pathogen responsible for substantial economic losses in aquaculture and human health) from influent to effluent, probably due to prolonged β-lactam selection pressure and aquatic nature of A. veronii. This enrichment resulted in a significantly higher abundance of A. veronii than other aquatic samples worldwide. Furthermore, the closest evolutionary relative to the retrieved A. veronii was an isolate obtained from the stool of a local diarrhea patient. These findings highlighted a substantial public health risk posed by antibiotic-manufacturing wastewater treatment, underlining its potential role in enriching and disseminating zoonotic antibiotic-resistant pathogens. Beyond chemical monitoring, enhanced surveillance of antibiotic-resistant pathogens and antibiotic resistance genes is needed in effluent discharge standard for antibiotic-manufacturing wastewater treatment plants.

Wang, Xingshuo↗