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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 1,063 records · Page 59
All sourcesNASA NTRSDOE OSTI
NASA NTRS1979

Causes of high pressure compressor deterioration in service

The high mechanical reliability and low deterioration rate of the JT9D high-pressure compressor results in long utilization without exceeding engine operational limits. The increasing cost and decreasing supply of fuel have focused attention on the fuel burned implications of such high time use without refurbishment. The paper presents the results of JT9D high pressure compressor studies. The mechanical deterioration of the JT9D high-pressure compressor gaspath parts versus increasing service usage, documented from inspection of service parts, is presented and discussed including changes in airfoil roughness, blade length, airfoil contour and outer air seal trench characteristics. An estimate of the performance loss versus usage is related to each type of damage. The combined estimated high-pressure compressor performance loss for all mechanisms determined from part inspection is compared to historical engine test data to establish the validity of the predicted loss levels. The effect of cold section refurbishment on engine fuel consumption recovery and the results of an optimization study to determine the appropriate interval for high pressure compressor refurbishment are also reported.

Richardson, J. H.↗
NASA NTRS1982

The aerodynamic performance of several flow control devices for internal flow systems

An experimental reseach and development program was undertaken to develop and document new flow-control devices for use in the major modifications to the 40 by 80 Foot wind tunnel at Ames Research Center. These devices, which are applicable to other facilities as well, included grid-type and quasi-two-dimensional flow straighteners, louver panels for valving, and turning-vane cascades with net turning angles from 0 deg to 90 deg. The tests were conducted at model scale over a Reynolds number range from 2 x 100,000 to 17 x 100,000, based on chord. The results showed quantitatively the performance benefits of faired, low-blockage, smooth-surface straightener systems, and the advantages of curved turning-vanes with hinge-line gaps sealed and a preferred chord-to-gap ratio between 2.5 and 3.0 for 45 deg or 90 deg turns.

Eckert, W. T.↗
NASA NTRS1988

International interface design for Space Station Freedom - Challenges and solutions

The definition of interfaces for the International Space Station is discussed, with a focus on negotiations between NASA and ESA. The program organization and division of responsibilities for the Space Station are outlined; the basic features of physical and functional interfaces are described; and particular attention is given to the interface management and documentation procedures, architectural control elements, interface implementation and verification, and examples of Columbus interface solutions (including mechanical, ECLSS, thermal-control, electrical, data-management, standardized user, and software interfaces). Diagrams, drawings, graphs, and tables listing interface types are provided.

Mayo, Richard E.↗
NASA NTRS2000

BOREAS Hardcopy Maps

Boreal Ecosystem-Atmospheric Study (BOREAS) hardcopy maps are a collection of approximately 1,000 hardcopy maps representing the physical, climatological, and historical attributes of areas covering primarily the Manitoba and Saskatchewan provinces of Canada. These maps were collected by BOREAS Information System (BORIS) and Canada for Remote Sensing (CCRS) staff to provide basic information about site positions, manmade features, topography, geology, hydrology, land cover types, fire history, climate, and soils of the BOREAS study region. These maps are not available for distribution through the BOREAS project but may be used as an on-site resource. Information is provided within this document for individuals who want to order copies of these maps from the original map source. Note that the maps are not contained on the BOREAS CD-ROM set. An inventory listing file is supplied on the CD-ROM to inform users of the maps that are available. This inventory listing is available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). For hardcopies of the individual maps, contact the sources provided.

Hall, Forrest G.↗
NASA NTRS2014

Integration of Earth Remote Sensing into the NOAA/NWS Damage Assessment Toolkit

Following the occurrence of severe weather, NOAA/NWS meteorologists are tasked with performing a storm damage survey to assess the type and severity of the weather event, primarily focused with the confirmation and assessment of tornadoes. This labor‐intensive process requires meteorologists to venture into the affected area, acquire damage indicators through photos, eyewitness accounts, and other documentation, then aggregation of data in order to make a final determination of the tornado path length, width, maximum intensity, and other characteristics. Earth remote sensing from operational, polar‐orbiting satellites can support the damage assessment process by helping to identify portions of damage tracks that are difficult to access due to road limitations or time constraints by applying change detection techniques. In addition, higher resolution commercial imagery can corroborate ground‐based surveys by examining higher‐resolution commercial imagery. As part of an ongoing collaboration, NASA and NOAA are working to integrate near real‐time Earth remote sensing observations into the NOAA/NWS Damage Assessment Toolkit, a handheld application used by meteorologists in the survey process. The team has recently developed a more streamlined approach for delivering data via a web mapping service and menu interface, allowing for caching of imagery before field deployment. Near real‐time products have been developed using MODIS and VIIRS imagery and change detection for preliminary track identification, along with conduits for higher‐resolution Landsat, ASTER, and commercial imagery as they become available. In addition to tornado damage assessments, the team is also investigating the use of near real‐time imagery for identifying hail damage to vegetation, which also results in large swaths of damage, particularly in the central United States during the peak growing season months of June, July, and August. This presentation will present an overview of recent activities, challenges and successes, best practices, and opportunities for future work and collaboration.

Molthan, Andrew↗
DOE OSTI2016

Supporting the Development of Soft-Error Resilient Message Passing Applications using Simulation

Radiation-induced bit flip faults are of particular concern in extreme-scale high-performance computing systems. This paper presents a simulation-based tool that enables the development of soft-error resilient message passing applications by permitting the investigation of their correctness and performance under various fault conditions. The documented extensions to the Extreme-scale Simulator (xSim) enable the injection of bit flip faults at specific of injection location(s) and fault activation time(s), while supporting a significant degree of configurability of the fault type. Experiments show that the simulation overhead with the new feature is ~2,325% for serial execution and ~1,730% at 128 MPI processes, both with very fine-grain fault injection. Fault injection experiments demonstrate the usefulness of the new feature by injecting bit flips in the input and output matrices of a matrix-matrix multiply application, revealing vulnerability of data structures, masking and error propagation. xSim is the very first simulation-based MPI performance tool that supports both, the injection of process failures and bit flip faults.

Engelmann, Christian↗
DOE OSTI2022

Methods and systems for evaluating and improving distribution-grid observability

This document describes systems and techniques for evaluating and improving distribution-grid observability. These systems and techniques allow engineers to quantify the observability of a distribution grid, which represents an ability to combine actual measurements and various types of computations (e.g., analytics, estimators, forecasters), from a system model. Distribution engineers can also identify islands of observability where operating parameters, including voltages, currents, and power flows, can be determined from available sensor readings. By exclusion, distribution engineers can similarly identify areas of the distribution grid with observability deficiencies that may require additional instrumentation to maintain proper operation. Distribution engineers, using an iterative or automated process, can determine the observability of the system model with new or relocated sensors to generate a sensor allocation plan. The sensor allocation plan can indicate the number and location of sensors to either maximize observability for a fixed sensor cost or minimize sensor cost for predetermined observability.

Reiman, Anthony P.↗
NASA NTRS1981

Future fuels and engines for railroad locomotives. Volume 2: Technical document

The potential for reducing the dependence of railroads on petroleum fuel, particularly Diesel No. 2 was studied. The study takes two approaches: to determine the use of Diesel No. 2 can be reduced through increased efficiency and conservation, and to use fuels other than Diesel No. 2 both in Diesel and other types of engines. Synthetic hydrocarbon fuels, probably derived from oil shale, will be needed if present diesel-electric locomotives continue to be used.

Liddle, S. G.↗
DOE OSTI2022

Using high-throughput amplicon sequencing to determine diet of generalist lady beetles in agricultural landscapes

Determining feeding relationships is central to understanding biological control potential in the field. However, methods to differentiate actual (or realized) feeding relationships from potential feeding relationships is lacking especially for small, generalist predators such as lady beetles. In this study, we used DNA metabarcoding approaches to characterize actual feeding relationships of lady beetles (Coccinellidae) in the field and validated our methods with a lab study. We first asked whether high-throughput amplicon sequencing (HTS) can characterize diets of lady beetles ranging from monotypic diets to diverse diet mixtures in the lab. We then examined whether diet composition and breadth of lady beetles collected from different habitat types in southern WI varied between monocultures of soybean and corn, diverse tallgrass prairie, and urban habitats. Lastly, we asked whether different body or tissue types (partial-body versus whole-body specimens) would change the likelihood of prey detection for both studies. In our controlled lab study, we found that HTS can accurately assess diet composition and diet breadth for lady beetle populations, but at the individual level, HTS has limitation for individuals feeding on more than three species of prey at any given time. In our field study, we documented lower prey richness and diet breadth in corn compared to soybean and grassland, and greater prey DNA in regurgitants than in whole-body specimens. Finally, we found that reduced diet diversity was associated with an increased prevalence of intraguild predation, but that habitat and prey diversity are not necessarily correlated. The prey detection rates (proportion of specimens with prey DNA) in our study were comparable to other studies (55% in the lab study, 33% in field study) and varied with diet composition and habitat type. Furthermore, the relatively low detection rates suggest that many consumer individuals would need to be assayed to fully assess diet diversity, especially in diverse systems.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2012

Oppenheimer's Box of Chocolates: Remediation of the Manhattan Project Landfill at Los Alamos National Laboratory - 12283

Material Disposal Area B (MDA B) is the oldest radioactive waste disposal facility at Los Alamos National Laboratory. Operated from 1944-48, MDA B was the disposal facility for the Manhattan Project. Recognized as one of the most challenging environmental remediation projects at Los Alamos, the excavation of MDA B received $110 million from the American Recovery and Reinvestment Act of 2009 to accelerate this complex remediation work. Several factors combined to create significant challenges to remediating the landfill known in the 1940's as the 'contaminated dump'. The secrecy surrounding the Manhattan Project meant that no records were kept of radiological materials and chemicals disposed or of the landfill design. An extensive review of historical documents and interviews with early laboratory personnel resulted in a list of hundreds of hazardous chemicals that could have been buried in MDA B. Also, historical reports of MDA B spontaneously combusting on three occasions -with 50-foot flames and pink smoke spewing across the mesa during the last incident in 1948-indicated that hazardous materials were likely present in MDA B. To complicate matters further, though MDA B was located on an isolated mesa in the 1940's, the landfill has since been surrounded by a Los Alamos commercial district. The local newspaper, hardware store and a number of other businesses are located directly across the street from MDA B. This close proximity to the public and the potential for hazardous materials in MDA B necessitated conducting remediation work within protective enclosures. Potential chemical hazards and radiological inventory were better defined using a minimally intrusive sampling method called direct push technology (DPT) prior to excavation. Even with extensive sampling and planning the project team encountered many surprises and challenges during the project. The one area where planning did not fail to meet reality was safety. There were no serious worker injuries and the minor injuries recorded were those common to construction type activities. Extensive monitoring along the site boundary demonstrated that no hazardous chemicals were released and radiological dose to the public was within administrative limits. More than three years of effort by the LANL project team went into the planning for remediation of Material Disposal Area B. Hundreds of historical documents were reviewed; retired personnel were extensively interviewed and noninvasive techniques were used to characterize the site. The information collected was incorporated into the safety requirements, cost estimate, schedule and primary execution plan for the project. Ultimately the waste volume managed by the project approached 40000 m{sup 3}, more than double the original project estimate. This increase had a major impact on both project cost and schedule. Nuclear safety requirements for the project were based on an estimated MDA B radionuclide inventory of 12 PE-Ci. When excavation was complete over 123 PE-Ci had been removed from the trenches. The radionuclide inventory at MDA B was an order of magnitude higher than estimated. Work at MDA B could not have proceeded without the safety basis exemption from DOE-HQ. The one area where planning did not fail to meet reality was safety. There were no serious worker injuries and the minor injuries recorded were those common to construction type activities. Extensive monitoring along the site boundary demonstrated that no hazardous chemicals were released and radiological dose to the public was within administrative limits. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS1970

New type of nonflammable paper

Nonflammable paper is made from fibers of chrysotile asbestos, beta-glass fibers, glass microfibers, and a little nonflammable organic binder. It does not propagate flame in an atmosphere of 16.5-psig oxygen, and it is resistant to rot and mold, making it acceptable as wrapping material and for stored documents.

Armstrong, G. K.↗
NASA NTRS1994

Produce documents and media information

Lightning data and information were collected from the United States, Germany, France, Brazil, China, and Australia for the dual purposes of compiling a global lightning data base and producing publications on the Marshall Space Flight Center's lightning program. Research covers the history of lightning, the characteristics of a storm, types of lightningdischarges, observations from airplanes and spacecraft, the future fole of planes and spacecraft in lightning studies, lightning detection networks, and the relationships between lightning and rainfall. Descriptions of the Optical Transient Dectector, the Lightning Imaging Sensor, and the Lightning Mapper Sensor are included.

Alzmann, Melanie A.↗
DOE OSTI2011

The Tevatron Wide Band Longitudinal Coupled Bunch Mode Dampers - an Account From Its Commissioning to Its Decommissioining

The Tevatron longitudinal dampers were built in 2002 to stop the proton beam from spontaneously blowing up during high energy physics. The system has been operational since then and has been very successful in keeping the beam stable. In October 2 011, the Tevatron will be shutdown and the dampers decommissioned. The goal of this paper is to document the 9 year experience in the operation of these dampers, account for the design choices made at the time, describe its commissioning, and its performa nce during its working life. Included will be a discussion on the type of instability which required the damper to be built.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

Grid Modeling for the SunShot Vision Study

This document describes the use of production cost modeling in the SunShot Vision study, including methods used to create the SunShot Vision scenarios, their implementation in the Gridview model, and assumptions regarding transmission system and operation of each generator type. It also describes challenges and limitations of modeling solar generation technologies in production cost models, andsuggests methods for improving their representation in current models.

14 SOLAR ENERGY↗
DOE OSTI2018

Prototype Courthouse Building Energy Model: Building and System Characteristics

As part of the Department of Energy’s support of ANSI/ASHRAE/IES Standard 90.1 and the International Energy Conservation Code, researchers at Pacific Northwest National Laboratory apply a suite of prototype buildings covering 80% of the commercial building floor area in the United States for new construction. Efforts have begun to cover 90% of the commercial building floor area in the United States by developing prototype models for additional building types that include supermarket, laboratory, place of worship, public order and safety, and public assembly. “Courthouse” is a subcategory under the “Public Order and Safety” building type category defined by the Commercial Buildings Energy Consumption Survey (CBECS); other subcategories include police station, fire station, and detention and correctional facilities (i.e., jail, reformatory, or penitentiary). Oak Ridge National Laboratory used building design guides, databases, and documented courthouse projects, supplemented by personal communication with courthouse facility planning and design experts, to systematically conduct research on the courthouse building and system characteristics. This report documents this research and reports the building and system characteristics necessary for developing a Courthouse prototype building energy model to be included in the Commercial Building Prototype Model suite.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2021

Generic Pressurized Water Reactor Model for SAPHIRE

Generic Pressurized Water Reactor Model for SAPHIRE This report contains a data dump from a SAPHIRE Generic Pressurized Water Reactor (PWR) model. The intent is to have this information reviewed for export control and classification so that the generic model can be used external to INL. The facility model is not applicable to any existing nuclear reactors. The Generic PWR model does not represent any existing power plant and was created to support research and training purposes. Three distinct types of data are used to create a SAPHIRE risk model: - Event trees representing typical PWR sequences - Fault trees representing generic system performance - Basic events (e.g., component failure information) Where possible, we have taken information from publicly available documents and referenced that information tagged to a specific item.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2023

Thermal Spray toolpath development for a capped cylinder (“cake pan”) substrate

A near net shape coating is desired to be applied to the outer surface of a capped cylinder (“cake pan”) type substrate using thermal spray technology. A capped cylinder geometry is more complex than simple coupon-level substrate substrates (e.g., flat panels, cylinders) and thus requires a more complex toolpath to deposit a uniform coating. This report documents a practical theoretical approach to calculating relative torch-to-substrate speeds for coating the cylindrical, corner, and cap region of a rotating capped cylinder based on fundamental thermal spray toolpath principles. A preliminary experimental test deposited a thermal spray coating onto a mock substrate using toolpath speeds calculated by the theoretical approach proposed. The mock substrate was metallographically inspected to assess coating uniformity across the cylindrical, corner, and cap region. Inspection of the mock substrate revealed qualitatively uniform coating microstructure and thickness where theoretically predicted, demonstrating the viability of the proposed toolpath method and associated calculations. Pathways forward to optimizing coating uniformity at the cap center are proposed as near term suggested future work.

42 ENGINEERING↗