Influence of grain boundary properties on spall strength: Grain boundary energy and excess volume
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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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The objective of this work is to develop and test a set of general guidelines for choosing parameters to be used in the state-of-the-art actuator line method (ALM) for modeling wind turbine blades in computational fluid dynamics (CFD). The actuator line method is being increasingly used for the computation of wake interactions in large wind farms in which fully blade-resolving simulations are expensive and require complicated rotating meshes. The focus is on actuator line behavior using fairly isotropic grids of low aspect ratio typically used for large-eddy simulation (LES). Forces predicted along the actuator lines need to be projected onto the flow field as body forces, and this is commonly accomplished using a volumetric projection. In this study, particular attention is given to the spanwise distribution of the radius of this projection. A new method is proposed where the projection radius varies along the blade span following an elliptic distribution. The proposed guidelines for actuator line parameters are applied to the National Renewable Energy Laboratory's (NREL's) Phase VI rotor and the NREL 5-MW turbine. Results obtained are compared with available data and the blade-element code XTurb-PSU. As a result, it is found that the new criterion for the projection radius leads to improved prediction of blade tip loads for both blade designs.
This dataset contains input and result files of computational simulations with the SCALE code system. The simulations cover radionuclide inventory and reactivity analyses of various advanced reactors. Users wanting to reproduce results from this dataset are required to obtain a license to the SCALE code system for which details on the distribution can be found here: https://www.ornl.gov/scale/releases
This dataset contains input and result files of computational simulations with the SCALE code system. The simulations cover radionuclide inventory generation, criticality calculations, and dose rate/shielding analyses of various advanced reactors. Users wanting to reproduce results from this dataset are required to obtain a license to the SCALE code system for which details on the distribution can be found here: https://www.ornl.gov/scale/releases
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This Project's third year of implementation in 2007-2008, the final year, as designated by Elizabeth City State University (ECSU), in cooperation with the National Association of Mathematicians (NAM) Inc., in an effort to promote research and research training programs in computational science & scientific visualization (CSSV). A major goal of the Project was to attract the energetic and productive faculty, graduate and upper division undergraduate students of diverse ethnicities to a program that investigates science and computational science issues of long-term interest to the Department of Energy (DoE) and the nation. The breadth and depth of computational science & scientific visualization and the magnitude of resources available are enormous for permitting a variety of research activities. ECSU's Computational Science-Science Visualization Center will serve as a conduit for directing users to these enormous resources.
The Department of Energy's Space and Defense Power Systems program provides a unique capability for supplying power systems that function in remote or hostile environments. This capability has been functioning since the early 1960s and counts the National Aeronautics and Space Administration as one of its most prominent customers. This enabling technology has assisted the exploration of our solar system including the planets Jupiter, Saturn, Mars, Neptune, and soon Pluto. This capability is one-of-kind in the world in terms of its experience (over five decades), breadth of power systems flown (over two dozen to date) and range of power levels (watts to hundreds of watts). This document describes the various components of that infrastructure, work scope, funding needs, and its strategic plans going forward.
Government policy is one of the most important factors in engaging the private sector in providing universal access to electricity. In particular, the private sector is well positioned to provide decentralized electricity products and services. While policy uncertainty and regulatory barriers can keep enterprises and investors from engaging in the market, targeted policies can create opportunities to leverage private investment and skills to expand electricity access. However, creating a sustainable market requires policies beyond traditional electricity regulation. The report reviews the range of policy issues that impact the development and expansion of a market for decentralized electricity services from establishing an enabling policy environment to catalyzing finance, building human capacity, and integrating energy access with development programs. The case studies in this report show that robust policy frameworks--addressing a wide range of market issues--can lead to rapid transformation in energy access. The report highlights examples of these policies in action Bangladesh, Ethiopia, Mali, Mexico, and Nepal.
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Mathematical techniques used in minimum variance orbital navigation and guidance, midcourse phase, lunar parking, descent orbits, landing, ascent, and rendezvous
Atomic line intensity tables for ionized iron atom at high temperatures
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