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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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AI is increasingly used in critical infrastructure, but it's often a “black box” that is difficult to understand. AIBOMs, or AI Bill of Materials, are one way to increase AI transparency and accountability. They can also be used in automated cyber defense. AIBOMs are a new concept with challenges to widespread adoption, but their potential in cybersecurity makes them a worthwhile investment.
The current Electronic Data Management System (EDMS) makes it difficult to efficiently access information in critical time frames. This project explored ways to allow Environmental Support and Services staff the ability to efficiently access documents with necessary historic information while leveraging existing data classification methods and the capabilities of EDMS.
The Deep Space Gateway requires thruster systems to maintain spatial position. One control system being considered involves Hall thrusters. Historically, Hall thruster discharge channels have used several grades of hot-pressed hexagonal boron nitride. This study compliments data presented at ICACC (International Conference and Expo on Advanced Ceramics and Composites) 2018 and investigates the fracture toughness and slow crack growth parameters of several commercially available boron nitride grades including HP, M, M26, and Shapal Hi-M. The prior work revealed that some grades of BN absorb water and change strength thus presenting a philosophical conundrum on crack growth test methods. Advantages of different test methods will be discussed. The grades selected for this study are of interest because their available billet size is sufficient for Hall thruster discharge channels, or because they have heritage in Hall thruster applications. Ultimately, the data will be used to perform material selection, system design and reliability analyses.
Slides of the presentation given by Harry Abernathy from the National Energy Technology Laboratory at the 2023 International Conference and Expo on Advanced Ceramics and Composites. The presentation was an overview of NETL's solid oxide cell performance degradation modeling, including a demonstration of the impact of microstructural analysis methods on the resulting degradation simulations.
47th International Conference and Expo on Advanced Ceramics and Composites (ICACC 2023), Daytona Beach, FL, January 22-27, 2023
47th International Conference and Expo on Advanced Ceramics and Composites (ICACC 2023), Daytona Beach, FL, January 22-27, 2023
47th International Conference and Expo on Advanced Ceramics and Composites (ICACC 2023), Daytona Beach, FL, January 22-27, 2023
47th International Conference and Expo on Advanced Ceramics and Composites (ICACC 2023), Daytona Beach, FL, January 22-27, 2023
Presentation given by NETL solid oxide cell (SOC) group leader Harry Abernathy reviewing NETL's SOC modeling capabilities for an invited talk at the 48th International Conference and Expo on Advanced Ceramics and Composites January 28 - February 2, 2024.
Conference presentation at International Fuel and Ethanol Workshop and Expo (FEW), Omaha, Nebraska, June 13, 2023. An overview of the Plains CO 2 Reduction (PCOR) Partnership Initiative and active commercial carbon capture, utilization, and storage (CCUS) activity in the region. Includes solutions for CCUS deployment challenges.
In this paper, an experimental and numerical investigation of internal cooling channels with rib turbulators is presented with sCO 2 as the working fluid at process conditions (pressure-20.7 MPa and temperature up to 150 °C). The effect of channel aspect ratio up to 2:1 on thermal-hydraulic performance is explored in additively manufactured rectangular channels and square channels, both with and without 60 deg ribs on the top and bottom sides. The Wilson-plot method is employed to experimentally measure channel-averaged Nusselt number over a Reynolds number range up to 370,000. The friction factor is calculated from pressure drop and mass flow rate and additionally, the overall thermal performance factor (TPF) is reported. A companion computational fluid dynamics (CFD) simulation is performed for the rib turbulated cooling configurations reported in the experiments using the Reynolds average Navier–Stokes-based turbulence model. The objective of the numerical study is to gain insight into the local heat transfer augmentation in the ribbed channels as a result of varying the aspect ratio, channel configuration (square versus rectangular), operating conditions (Reynolds number) and the surface roughness, an inherent outcome of the additive manufacturing process. Surface roughness is simulated using sand grain roughness height (K S ) calculated from the experimental data, and a comparison is presented with the corresponding channel configuration with varying surface roughness heights starting from smooth surfaces (K S = 0). Experimental results indicate that the heat transfer augmentation is negligible in the rectangular channels with ribs on the long side compared to the square channel. However, it is enhanced by 60% in comparison to placing ribs on the shorter side. The TPF remains constant at around 1 for the entire range of Reynolds numbers consistent with prior work at the National Energy Technology Laboratory (NETL). Here, the simulation results highlight that increased surface roughness can have a favorable considerable influence on Nusselt number and overall thermal performance enhancement.
This NASA Conference Publication features select papers and PowerPoint presentations from the Education and Training Track of MODSIM World 2007 Conference and Expo. Invited speakers and panelists of national and international renown, representing academia, industry and government, discussed how modeling and simulation (M&S) technology can be used to accelerate learning in the K-16 classroom, especially when using M&S technology as a tool for integrating science, technology, engineering and mathematics (STEM) classes. The presenters also addressed the application ofM&S technology to learning and training outside of the classroom. Specific sub-topics of the presentations included: learning theory; curriculum development; professional development; tools/user applications; implementation/infrastructure/issues; and workforce development. There was a session devoted to student M&S competitions in Virginia too, as well as a poster session.
ASME Turbo Expo 2023
Over the past several years, a number of candidate scenarios for the human exploration of Mars have been advanced. These have had a range of mission objectives, scope, scale, complexity and probable cost. The Exploration Programs Office (ExPO) has developed a reference Mars exploration program and a means of comparing it to other proposed Mars programs. The reference program was initiated in a workshop of Mars exploration advocates which defined two objectives of equal importance for early Mars exploration - understanding Mars and understanding the potential of Mars to support humans. These goals were used to define a set of transportation and surface elements that could carry out a robust exploration program. The approach to comparing alternate architectures has three principal parts: (1) Bringing the architectures into rough commonality in terms of surface mission objectives and hardware capabilities; (2) Providing a common level of human support for flights to and from Mars; and (3) Comparing the complexity of the elements needed to carry out the program and using partial redundancy to approximate the same statistical probability of mission success. This top-level approach has been applied to the ExPO reference program, the 'Mars Directs strategy (Zubrin, 1991) and the Stanford International Mars Mission (Lusignan, 1992).
William and Mary Science Career Expo–Engineering
Abstract Additive manufacturing processes, such as direct metal laser sintering (DMLS), enable the creation of novel turbine cooling internal passages and systems. However, the DMLS method produces a significant and unique surface roughness. Previous work in scaled passages analyzed pressure losses and friction factors associated with the rough surfaces, as well as investigated the velocity profiles and turbulent flow characteristics within the passage. In this study, the heat transfer characteristics of scaled additively manufactured surfaces were measured using infrared (IR) thermography. Roughness panels were CNC machined from plates of aluminum 6061 to create near isothermal roughness elements when heated. Fluid resistance differences between the aluminum roughness panels and roughness panels constructed from ABS plastic using the same roughness patterns from McClain et al. (2020, “Flow in a Simulated Turbine Blade Cooling Channel With Spatially Varying Roughness Caused by Additive Manufacturing Orientation,” ASME Turbo Expo 2020, Turbomachinery Technical Conference and Exposition, Virtual Conference, Sept. 21–25, GT2020-16069) were investigated. Finally, the overall thermal performance enhancements and friction losses were assessed through the calculation of surface averaged “global thermal performance” ratios. The global thermal performance characterizations indicate results in-line with those found for traditional commercial roughness and slightly below traditional internal passage convection enhancement methods such as swirl chambers, dimples, and ribs. The passages investigated in this study do not include compressibility effects or the long-wavelength artifacts and channel geometric deviations observed by Wildgoose et al. (2020, “Impact of Additive Manufacturing on Internal Cooling Channels with Varying Diameters and Build Directions,” ASME Turbo Expo 2020, Turbomachinery Technical Conference and Exposition, Virtual Conference, Sept. 21–25, GT2020-15049). However, the results of this study indicate that, based on the roughness augmentation alone, artificial convective cooling enhancers such as turbulators or dimples may still be required for additively manufactured turbine component cooling.
The function of Kennedy Space Center's Center Planning and Development (CPD) directorate is to develop partnerships with the commercial space industry, academia, and other non-NASA government agencies to use KSC's facilities, technical capabilities, technologies and expertise, while building on existing partnerships. As an intern for the Spaceport Planning Office within the CPD, I played an essential part in promoting these opportunities by assisting the Marketing Specialist with organizing CPD's multi-booth exhibit for KSC's 2014 Innovation Expo. I was also responsible for gathering/reviewing video clips of interviews from existing partners to be used as potential footage for video testimonials that would be used to educate the public on KSC. My last project was to develop a standard presentation highlighting the benefits and potential of partnering with KSC, which would be used by KSC partnership development managers (PDMs) when presenting externally to potential partners. With these various projects and limited timeframe to complete each, learning to effectively manage my time and actively multitask was imperative.
This paper presents the results of the HELIOS (Hardened Extremely Long Life In-formation Optical Storage) mission on the International Space Station (ISS) which tested a unique solution for the long-term storage and retrieval of data in space. For this mission Creative Technology (CTech) developed test media—termed WORF (Write Once, Read Forever)—to validate whether this patented technology will survive all critical parameters for harsh space-based environments including microgravity and ionizing radiation. The HELIOS experiment confirmed that the WORF media is impervious to ionizing radiation, microgravity, solar (plasma) eruptions, and the stress from 8 Gs of the launch including extreme temperature expo-sure. The principal results indicate that there has been no discernible degradation of the media after 8 months on the ISS as compared to a control set of media stored on the ground. This data validated the media’s survivability for harsh space environments for long-term and deep space missions. In addition to the space environment, we are confident that WORF technology can be used for data storage where space-related and other long-term or archival integrity is critical such as: geospatial collections from satellites; space weather archives; past, ongoing, and future space mission media and documentation files; the deep space Gate-way program; as well as Big Data applications such as the Vera C. Rubin astronomical observatory (formerly the LSST). WORF technology for the HELIOS experiment uses a proven archival media, redesigned, re-purposed and patented by CTech to store digital data for long periods, measured in decades and possibly centuries. The media stores standing waves embedded in a substrate that capture the precise col-ors or wavelengths projected onto the media. The colors represent numerical data, with each data location storing multiple superimposed wavelengths, which facilitate the storage of multiple data bytes (rather than just zeros and ones); advanced mathematical permutations allow for extremely large data density equal to or greater than contemporary data storage de-vices. These colors cannot fade or degrade over time since the standing waves are physically stabilized (fully oxidized) metallic silver; no dyes are embedded for this storage system, and silver ions resist micro-bacterial and fungal contamination