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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 991 records · Page 55

Core-Shell Oxidative Aromatization Catalysts for Single Step Liquefaction of Distributed Shale Gas (Final Technical Report)

The objective of this project was to design and demonstrate a core-shell structured multifunctional catalyst to convert the light (dry) components of shale gas into liquid aromatic compounds (primarily benzene and toluene) in a single step. Operated in a modular oxidative aromatization system (OAS) under a cyclic redox scheme, the novel catalyst and process can significantly improve the value and transportability of distributed shale gas. Since the project started, each quarter addressed a different set of tasks related to the completion of the milestone detailed in the project award. The yearly summaries of these tasks are summarized below: Q1-Q4: • Conducted project planning and literature search. • Investigated a number of SHC redox catalysts using thermogravimetric analysis and fixed-bed reactor experiments. • Initiated process modeling towards generating two process models for the methane DHA base case and OAS process. • Developed DHA catalysts capable of producing >500 g/kg-cat-hr aromatics at 80% or greater aromatics selectivity at 700°C. Q5-Q8: • Developed alternative approaches with sequential bed configurations to enhance the aromatic yields based on OCM+DHA • Improved the zeolite synthesis efficiency by using the microwave-assisted technique and investigated the synthesis conditions on the zeolite yield, crystalline structure and morphology • Constructed a set of Aspen Plus process models with significant energy savings for OAS as compared to the base case non-oxidative DHA. • Adapted conventional hydrothermal method to be applicable to the microwave synthesizer unit for more efficient catalyst synthesis. • Studied the structure of the OCM catalyst and the dispersion of the carbonate in the redox reactions and in methane flow with Raman Spectroscopy. Q9-Q12: • Scaled up the catalyst synthesis with the microwave synthesis method. Based on its performance, procedural characterizations and catalytic performance testing were further conducted for the new microwave synthesized catalysts with the newly-developed product analysis procedure. • Developed the reaction system setup for the C2-DHA or OCM+DHA reaction product and achieved a better product collection-analysis method for the aromatic products with an improved carbon balance. The product from the OCM reaction exhibited complicated effects on the DHA catalyst. • Conducted additional OCM catalyst characterization using Near Ambient Pressure X-ray Photoelectron Spectroscopy and in situ Raman characterization • Validated the significant energy savings for OAS as compared to the base case non-oxidative DHA. Successfully set up the simulation model for the OCM+DHA+SHC reaction system based on the updated experimental results from NCSU. Q13-End of project: • Synthesized new zeolite catalysts by the microwave method, conducted characterizations (XRD, SEM, and TEM) and catalytic behavior testing. • Explored the “wet” C 2 H 6 and C 2 H 4 DHA reactions with using steam co-feed. A subsequent reduction as the regeneration step can regenerate the DHA catalyst and recover 99% activity of the fresh performance. • Achieved a 15.3% single-pass aromatic yield from methane by rationally combining the OCM and DHA at different temperatures. • Conducted a 105-hour stability test with an improved regeneration procedure, with an average aromatic yield of 13.8%. • Developed new catalyst and achieved a record-high 23.2% yield.

03 NATURAL GAS↗

Flight and Integrated Vehicle Testing: Laying the Groundwork for the Next Generation of Space Exploration Launch Vehicles

Integrated vehicle testing will be critical to ensuring proper vehicle integration of the Ares I crew launch vehicle and Ares V cargo launch vehicle. The Ares Projects, based at Marshall Space Flight Center in Alabama, created the Flight and Integrated Test Office (FITO) as a separate team to ensure that testing is an integral part of the vehicle development process. As its name indicates, FITO is responsible for managing flight testing for the Ares vehicles. FITO personnel are well on the way toward assembling and flying the first flight test vehicle of Ares I, th Ares I-X. This suborbital development flight will evaluate the performance of Ares I from liftoff to first stage separation, testing flight control algorithms, vehicle roll control, separation and recovery systems, and ground operations. Ares I-X is now scheduled to fly in summer 2009. The follow-on flight, Ares I-Y, will test a full five-segment first stage booster and will include cryogenic propellants in the upper stage, an upper stage engine simulator, and an active launch abort system. The following flight, Orion 1, will be the first flight of an active upper stage and upper stage engine, as well as the first uncrewed flight of an Orion spacecraft into orbit. The Ares Projects are using an incremental buildup of flight capabilities prior to the first operational crewed flight of Ares I and the Orion crew exploration vehicle in 2015. In addition to flight testing, the FITO team will be responsible for conducting hardware, software, and ground vibration tests of the integrated launch vehicle. These efforts will include verifying hardware, software, and grou handling interfaces. Through flight and integrated testing, the Ares Projects will identify and mitigate risks early the United States prepares to take its next giant leaps to the Moon and beyond.

Taylor, Jim↗

Flight and Integrated Vehicle Testing: Laying the Groundwork for the Next Generation of Space Exploration Launch Vehicles

Integrated vehicle testing will be critical to ensuring proper vehicle integration of the Ares I crew launch vehicle and Ares V cargo launch vehicle. The Ares Projects, based at Marshall Space Flight Center in Alabama, created the Flight and Integrated Test Office (FITO) as a separate team to ensure that testing is an integral part of the vehicle development process. As its name indicates, FITO is responsible for managing flight testing for the Ares vehicles. FITO personnel are well on the way toward assembling and flying the first flight test vehicle of Ares I, the Ares I-X. This suborbital development flight will evaluate the performance of Ares I from liftoff to first stage separation, testing flight control algorithms, vehicle roll control, separation and recovery systems, and ground operations. Ares I-X is now scheduled to fly in summer 2009. The follow-on flight, Ares I-Y, will test a full five-segment first stage booster and will include cryogenic propellants in the upper stage, an upper stage engine simulator, and an active launch abort system. The following flight, Orion 1, will be the first flight of an active upper stage and upper stage engine, as well as the first uncrewed flight of an Orion spacecraft into orbit. The Ares Projects are using an incremental buildup of flight capabilities prior to the first operational crewed flight of Ares I and the Orion crew exploration vehicle in 2015. In addition to flight testing, the FITO team will be responsible for conducting hardware, software, and ground vibration tests of the integrated launch vehicle. These efforts will include verifying hardware, software, and ground handling interfaces. Through flight and integrated testing, the Ares Projects will identify and mitigate risks early as the United States prepares to take its next giant leaps to the Moon and beyond.

Taylor, J. L.↗

Space Shuttle Software Development and Certification

Man-rated software, "software which is in control of systems and environments upon which human life is critically dependent," must be highly reliable. The Space Shuttle Primary Avionics Software System is an excellent example of such a software system. Lessons learn from more than 20 years of effort have identified basic elements that must be present to achieve this high degree of reliability. The elements include rigorous application of appropriate software development processes, use of trusted tools to support those processes, quantitative process management, and defect elimination and prevention. This presentation highlights methods used within the Space Shuttle project and raises questions that must be addressed to provide similar success in a cost effective manner on future long-term projects where key application development tools are COTS rather than internally developed custom application development tools

Orr, James K.↗

Status of Analysis and Manufacturability of Superconducting Wires with Low AC Losses

Superconductors can carry an order-of-magnitude higher current than room temperature copper wires and can do so with two orders-of-magnitude lower alternating current (AC) electrical losses. These advantages underlie our estimates that turboelectric propulsion of large aircraft can be enabled by superconducting machines. However, even the much smaller losses of superconductors pose thermal management issues at the low temperatures required for superconductivity, and predicting those losses and validating the predictions has been a developing process at NASA Glenn Research Center over the last decade. Since Glenn’s earliest assessments of the feasibility of fully superconducting machines for turboelectric propulsion, the available models of AC losses in superconductors have changed significantly, as well as the state of development of superconducting wire for the coils of electric machines. While the models available to us have improved significantly, the value of the AC losses predicted by these models have only increased as more fidelity was developed. The fabrication of medium temperature superconducting wires (Tc near 40 K) has advanced, and wires can be produced with finer filaments and tighter twisting than a decade ago. However, the ideal wire configurations, developed decades ago for low temperature superconductors (Tc < 25 K), still elude manufacturers of medium and high temperature (Tc > 77 K) superconductors. This report discusses the developments, the current limitations, and the expectations that future configurations of superconducting wire can yet be produced that will provide suitably low AC losses for the aircraft propulsion application. The report presents a basic discussion of the types of AC losses in superconductors, followed by a discussion of the evolution of our understanding of the practical consequences of those AC losses. Next, there is a discussion of the superconducting wire configurations that have been developed, which were partially guided by that understanding. A brief discussion of the modes of removing the heat produced by the losses is presented. Lastly, a comparison is presented between losses in currently available MgB2 wire and other important cases, including copper at room temperature, copper at liquid hydrogen temperature, and expected future MgB2 wire. Room temperature copper has 100 times the loss of today’s MgB2 and 300 times the expected loss of future MgB2. That implies we can expect much higher efficiency from fully superconducting machines than from machines with copper stators, and high efficiency targets remain the driver behind investment in MgB2 development and medium temperature superconductor research.

superconducting motors↗

Opening the Door to Grid-Interactive Efficient Buildings with Energy Codes

Building codes represent standard design practice in the construction industry and must continually evolve to account for advancing technologies and innovative practices. Energy codes have historically focused on energy efficiency within buildings and across their systems. However, many of tomorrow's technologies go beyond efficiency and target increased flexibility. These demand flexibility (DF) measures can postpone or reduce building electric load based on price or other grid signals, and include smart appliances, connected lighting, and connected mechanical systems. Expanding codes to enable such grid-interactive efficient building (GEB) has the potential to influence their realization at scale, which will support renewable-energy grid-integration and building-sector decarbonization. However, considering DF measures in code development creates a new set of challenges for codes and the practices contained therein. This paper considers the role of building energy codes in enabling GEB. Specifically, it reviews the status of demand flexibility (DF) measures in current commercial building energy code. It examines the national model code development process and identifies components barring the consideration and inclusion of DF measures - including code scope, characterization and analysis of proposed new prescriptive measures, and accounting for time-of-day and geographic differences in their benefits. The paper presents findings from code development analyses that indicate the cost benefit of DF measures and the limitations associated with current code development conventions. To encourage building flexibility and improved energy resilience moving forward, recommendations are made for removing code development barriers and sanctioning DF measure consideration in future model codes.

Building Energy Codes and Standards, Grid-Interact↗

Data-driven Quasi-static Surrogate Model for Nuclear-powered Integrated Energy Systems

The integration of nuclear power into energy systems presents a promising avenue to address the growing global energy demands while minimizing greenhouse gas emissions. In this paper, we introduce a data-driven quasi-static surrogate model for nuclear-powered Integrated Energy Systems (IES) that comprises various components, including a small modular reactor (SMR), energy manifold (EM), balance of plant (BOP), high-temperature steam electrolysis (HTSE), and district heating (DH) system. Traditional physics-based models for these components often entail significant computational overhead and time consumption, necessitating the development of efficient surrogate models. The development of a complete surrogate model for the IES involves the creation of individual surrogate models for each component, leveraging machine learning techniques and simulated data. These isolated surrogate models are subsequently integrated, enabling a holistic view of the IES and reducing the computational burden associated with detailed physics-based simulations. This paper outlines the development process, validation, and the performance evaluation of the surrogate models. The findings shed light on the accuracy and applicability of the surrogate models in practical scenarios, demonstrating their potential to expedite the analysis of nuclear-powered IES and inform future research and development efforts.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Cold Spray Technology Applications for SRF Cavity Thermal and Mechanical Stabilization

The overall objective of the project is the development of a method allowing increased thermal and mechanical stabilization of SRF cavities by depositing a thick layer on the outer surface by cold-spray. Coating and testing of bi-metallic Nb/Cu and Nb/CuW samples were carried out to optimize the process parameters. The process developed on samples was applied to a single cell SRF cavity for proof-of-principle demonstration of improved thermal and mechanical stability.

36 MATERIALS SCIENCE↗

Rocket engine injection element characterization

Characterization of liquid rocket engine injection elements is an important part of the development process for rocket engine combustion devices. Modern nonintrusive instrumentation for flow velocity and spray droplet size measurement and automated, computer-controlled test facilities allow rapid, low-cost evaluation of injection element performance and behavior. Application of these methods in rocket engine development, paralleling their use in gas turbine engine development, will reduce rocket engine development cost and risk. Two types of liquid rocket engine injection elements have been characterized using such methods.

Cox, George B., Jr.↗

Injector element characterization methodology

Characterization of liquid rocket engine injector elements is an important part of the development process for rocket engine combustion devices. Modern nonintrusive instrumentation for flow velocity and spray droplet size measurement, and automated, computer-controlled test facilities allow rapid, low-cost evaluation of injector element performance and behavior. Application of these methods in rocket engine development, paralleling their use in gas turbine engine development, will reduce rocket engine development cost and risk. The Alternate Turbopump (ATP) Hot Gas Systems (HGS) preburner injector elements were characterized using such methods, and the methodology and some of the results obtained will be shown.

Cox, George B., Jr.↗

Pointing Error Budget Development and Methodology on the Psyche Project

The Psyche mission was selected by NASA as the 14th mission in the Discovery Program in 2017. The Psyche spacecraft utilizes solar electric propulsion, and will journey to the asteroid (16) Psyche during a 3.5 year trajectory after its planned 2022 launch. The spacecraft instrument suite includes a magnetometer, a multispectral imager, a gamma ray neutron spectrometer, and an X-band radio telecommunications system. It also includes the Deep Space Optical Communication technical demonstration. These instruments along with other spacecraft components require pointing accuracy to meet their scientific and engineering performance requirements. Early on in the project development, the team established a methodology by which pointing accuracy (knowledge and control) is analyzed against the system requirements by means of pointing error budgets and requirement allocations. A margin policy was implemented to ensure the instrument and engineering component pointing accuracy requirements will be met during verification and in flight. Psyche’s pointing management framework defines detailed rationales for the system and subsystem error allocations of the top level pointing accuracy requirements, with sufficient project level pointing margin, and supports end-to-end pointing requirement verification. This paper will present an overview of the Psyche project’s pointing error budget development process, and discuss the rationale behind the methodology. Psyche’s pointing budget methodology integrates best practices and lessons learned from heritage missions, while focusing on the specific needs of the Psyche spacecraft and its science instruments. Key challenges in the pointing error budget development will be reviewed, and a deep dive into two key Psyche pointing budgets are presented. The systems engineering of Psyche’s pointing budget methodology outlined in this paper will serve as a resource for future deep space missions.

Lai, Peter↗

Development of Subsonic Single Aft Engine (SUSAN) Attritable Research Vehicle (SARV) Wing Structure

This paper introduces a high-level overview of the design and development of the SUbsonic Single Aft eNgine (SUSAN) Attritable Research Vehicle (SARV) wing structure. Unique design considerations were made for the structural layout of the wing to include storage for batteries, distributed electric engines, and the requirement for the wing to be shippable in a cargo box. The wing structure development process will be discussed including the wing internal structure design evolution, the fabrication of the manufacturing demonstration vehicle, wing outer mold line design, integration of wing internal structure and wing skins, and finally integration of the wing with the fuselage structure. Additionally, the development of the wing skin design will be discussed while highlighting the wing skin manufacturing demonstration panels as well as composite testing for material characterization purposes.

wing structure↗

FTMP data acquisition environment

The Fault-Tolerant Multi-Processing (FTMP) test-bed data acquisition environment is described. The performance of two data acquisition devices available in the test environment are estimated and compared. These estimated data rates are used as measures of the devices' capabilities. A new data acquisition device was developed and added to the FTMP environment. This path increases the data rate available by approximately a factor of 8, to 379 KW/S, while simplifying the experiment development process.

Padilla, Peter A.↗

The Influence of Friction Stir Weld Tool Form and Welding Parameters on Weld Structure and Properties: Nugget Bulge in Self-Reacting Friction Stir Welds

Although friction stir welding (FSW) was patented in 1991, process development has been based upon trial and error and the literature still exhibits little understanding of the mechanisms determining weld structure and properties. New concepts emerging from a better understanding of these mechanisms enhance the ability of FSW engineers to think about the FSW process in new ways, inevitably leading to advances in the technology. A kinematic approach in which the FSW flow process is decomposed into several simple flow components has been found to explain the basic structural features of FSW welds and to relate them to tool geometry and process parameters. Using this modelling approach, this study reports on a correlation between the features of the weld nugget, process parameters, weld tool geometry, and weld strength. This correlation presents a way to select process parameters for a given tool geometry so as to optimize weld strength. It also provides clues that may ultimately explain why the weld strength varies within the sample population.

Schneider, Judy↗

Integrating Design and Manufacturing for a High Speed Civil Transport Wing

The aerospace industry is currently addressing the problem of integrating design and manufacturing. Because of the difficulties associated with using conventional, procedural techniques and algorithms, it is the authors' belief that the only feasible way to integrate the two concepts is with the development of an appropriate Knowledge-Based System (KBS). The authors propose a methodology for an aircraft producibility assessment, including a KBS, that addresses both procedural and heuristic aspects of integrating design and manufacturing of a High Speed Civil Transport (HSCT) wing. The HSCT was chosen as the focus of this investigation since it is a current NASA/aerospace industry initiative full of technological challenges involving many disciplines. The paper gives a brief background of selected previous supersonic transport studies followed by descriptions of key relevant design and manufacturing methodologies. Georgia Tech's Concurrent Engineering/Integrated Product and Process Development methodology is discussed with reference to this proposed conceptual producibility assessment. Evaluation criteria are presented that relate pertinent product and process parameters to overall product producibility. In addition, the authors' integration methodology and reasons for selecting a KBS to integrate design and manufacturing are presented in this paper. Finally, a proposed KBS is given, as well as statements of future work and overall investigation objectives.

Marx, William J.↗

An evaluation of programmer/analyst workstations

Very few automated tools were available to support software requirements analysis and design even though improvements in quality during these phases appear to offer the greatest leverage for improving the quality and productivity of the overall software development process. Recently, however, some such tools have appeared on the market. An industry survey, and an in-house evaluation of two commercial products by programmers and analysts was undertaken to determine which tool is the best to support programmers and analysts through life cycle development. A tool was selected for full implementation on a project, where complete analysis of software statistics over the system life cycle will determine whether or not quality and productivity improvements have actually occurred. The results of the industry survey and in-house evaluation are summarized.

Koerner, K.↗

Appendix C: Rapid development approaches for system engineering and design

Conventional system architectures, development processes, and tool environments often produce systems which exceed cost expectations and are obsolete before they are fielded. This paper explores some of the reasons for this and provides recommendations for how we can do better. These recommendations are based on DoD and NASA system developments and on our exploration and development of system/software engineering tools.

Source record↗

Development Context Driven Change Awareness and Analysis Framework

Recent work on workspace monitoring allows conflict prediction early in the development process, however, these approaches mostly use syntactic differencing techniques to compare different program versions. In contrast, traditional change-impact analysis techniques analyze related versions of the program only after the code has been checked into the master repository. We propose a novel approach, DeCAF (Development Context Analysis Framework), that leverages the development context to scope a change impact analysis technique. The goal is to characterize the impact of each developer on other developers in the team. There are various client applications such as task prioritization, early conflict detection, and providing advice on testing that can benefit from such a characterization. The DeCAF framework leverages information from the development context to bound the iDiSE change impact analysis technique to analyze only the parts of the code base that are of interest. Bounding the analysis can enable DeCAF to efficiently compute the impact of changes using a combination of program dependence and symbolic execution based approaches.

Sarma, Anita↗