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E-1 common analog model, 1969, July

Description: This report is the descriptive description of the E-1 common analog model
Date: July 1, 1969
Partner: UNT Libraries Government Documents Department
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2-1/2-D electromagnetic modeling of nodular defects in high-power multilayer optical coatings

Description: Advances in the design and production of high damage threshold optical coatings for use in mirrors and polarizers have been driven by the design requirements of high-power laser systems such as the proposed 1.8-MJ National Ignition Facility (NIF) and the prototype 12- kJ Beamlet laser system. The present design of the NIF will include 192 polarizers and more than 1100 mirrors. Currently, the material system of choice for high-power multilayer optical coatings with high damage threshold applications near 1.06 {mu}m are e-beam deposited HfO{sub 2}/Si0{sub 2} coatings. However, the optical performance and laser damage thresholds of these coatings are limited by micron-scale defects and insufficient control over layer thickness. In this report, we will discuss the results of our 2-1/2-D finite-element time- domain (FDTD) EM modeling effort for rotationally-symmetric nodular defects in multilayer dielectric HR coatings. We have added a new diagnostic to the 2-1/2-D FDTD EM code, AMOS, that enables us to calculate the peak steady-state electric fields throughout a 2-D planar region containing a 2-D r-z cross-section of the axisymmetric nodular defect and surrounding multilayer dielectric stack. We have also generated a series of design curves to identify the range of loss tangents for Si0{sub 2} and HfO{sub 2} consistent with the experimentally determined power loss of the HR coatings. In addition, we have developed several methods to provide coupling between the EM results and the thermal-mechanical simulation effort.
Date: July 1996
Creator: Molau, N. E.; Brand, H. R.; Kozlowski, M. R. & Shang, C. C.
Partner: UNT Libraries Government Documents Department
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2-D ACAR measurements of Ni/sub 3/A1

Description: In connection with a detailed study of the electronic structure and stability of the aluminides (Ni,Fe)/sub 3/Al, 2-D ACAR positron annihilation measurements were made on a Ni/sub 3/Al single crystal to study the Fermi surface. The results for Ni/sub 3/Al have been compared with results for pure Ni. Strong similarities were found for the electronic structures of these materials. Theoretical calculations of the Fermi surface for Ni/sub 3/Al are in good agreement with the experimental results. The GAMMA/sub 16/ sheet, not previously observed in any experiment, has now been observed for the first time in Ni/sub 3/Al. 14 refs., 10 figs.
Date: July 1987
Creator: Smedskjaer, L. C.; DasGupta, A.; Legnini, D. G. & Stahulak, M. D.
Partner: UNT Libraries Government Documents Department
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A 2-D imaging heat-flux gauge

Description: This report describes a new leadless two-dimensional imaging optical heat-flux gauge. The gauge is made by depositing arrays of thermorgraphic-phosphor (TP) spots onto the faces of a polymethylpentene is insulator. In the first section of the report, we describe several gauge configurations and their prototype realizations. A satisfactory configuration is an array of right triangles on each face that overlay to form squares when the gauge is viewed normal to the surface. The next section of the report treats the thermal conductivity of TPs. We set up an experiment using a comparative longitudinal heat-flow apparatus to measure the previously unknown thermal conductivity of these materials. The thermal conductivity of one TP, Y{sub 2}O{sub 3}:Eu, is 0.0137 W/cm{center dot}K over the temperature range from about 300 to 360 K. The theories underlying the time response of TP gauges and the imaging characteristics are discussed in the next section. Then we discuss several laboratory experiments to (1) demonstrate that the TP heat-flux gauge can be used in imaging applications; (2) obtain a quantum yield that enumerates what typical optical output signal amplitudes can be obtained from TP heat-flux gauges; and (3) determine whether LANL-designed intensified video cameras have sufficient sensitivity to acquire images from the heat-flux gauges. We obtained positive results from all the measurements. Throughout the text, we note limitations, areas where improvements are needed, and where further research is necessary. 12 refs., 25 figs., 4 tabs.
Date: July 1, 1991
Creator: Noel, B.W.; Borella, H.M. (Los Alamos National Lab., NM (United States)); Beshears, D.L.; Sartory, W.K.; Tobin, K.W.; Williams, R.K. (Oak Ridge National Lab., TN (United States)) et al.
Partner: UNT Libraries Government Documents Department
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2-D Imaging of Electron Temperature in Tokamak Plasmas

Description: By taking advantage of recent developments in millimeter wave imaging technology, an Electron Cyclotron Emission Imaging (ECEI) instrument, capable of simultaneously measuring 128 channels of localized electron temperature over a 2-D map in the poloidal plane, has been developed for the TEXTOR tokamak. Data from the new instrument, detailing the MHD activity associated with a sawtooth crash, is presented.
Date: July 8, 2004
Creator: Munsat, T.; Mazzucato, E.; Park, H.; Domier, C. W.; Johnson, M.; Luhmann, N. C. Jr. et al.
Partner: UNT Libraries Government Documents Department
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2-MW plasmajet facility thermal tests of concrete. [PWR and BWR]

Description: A test was made in the 2-Megawatt Plasmajet Facility to obtain experimental data relative to the thermal response of concrete to incident heat flux. 14.6 cm diameter by 8.0 cm long concrete cylinders were positioned in a supersonic flow of heated nitrogen from an arc heater. The end of the concrete cylinders impacted by the flow were subjected to heat fluxes in the range of 0.13 to 0.35 kW/cm/sup 2/. Measurements included cold wall surface heat flux and pressure distributions, surface and indepth temperatures, ablation rates, and surface emission spectrographs. The test was part of the Sandia light water reactor safety research program and complements similar tests made in the Radiant Heat Facility at heat fluxes from 0.03 to 0.12 kW/cm/sup 2/. A description of the tests and a tabulation of test data are included.
Date: July 1, 1977
Creator: Goin, Kenneth L.
Partner: UNT Libraries Government Documents Department
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3-D Seismic Methods for Geothermal Reservoir Exploration and Assessment--Summary

Description: A wide variety of seismic methods covering the spectrum from DC to kilohertz have been employed at one time or the other in geothermal environments. The reasons have varied from exploration for a heat source to attempting to find individual fractures producing hot fluids. For the purposes here we will assume that overall objective of seismic imaging is for siting wells for successful location of permeable pathways (often fracture permeability) that are controlling flow and transport in naturally fractured reservoirs. The application could be for exploration of new resources or for in-fill/step-out drilling in existing fields. In most geothermal environments the challenge has been to separate the ''background'' natural complexity and heterogeneity of the matrix from the fracture/fault heterogeneity controlling the fluid flow. Ideally one not only wants to find the fractures, but the fractures that are controlling the flow of the fluids. Evaluated in this work is current state-of-the-art surface (seismic reflection) and borehole seismic methods (Vertical Seismic Profiling (VSP), Crosswell and Single Well) to locate and quantify geothermal reservoir characteristics. The focus is on active methods; the assumption being that accuracy is needed for successful well siting. Passive methods are useful for exploration and detailed monitoring for in-fill drilling, but in general the passive methods lack the precision and accuracy for well siting in new or step out areas. In addition, MEQ activity is usually associated with production, after the field has been taken to a mature state, thus in most cases it is assumed that there is not enough MEQ activity in unproduced areas to accurately find the permeable pathways. The premise of this review is that there may new developments in theory and modeling, as well as in data acquisition and processing, which could make it possible to image the subsurface in much more detail than …
Date: July 14, 2003
Creator: Majer, E.L.
Partner: UNT Libraries Government Documents Department
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3-D TECATE/BREW: Thermal, stress, and birefringent ray-tracing codes for solid-state laser design

Description: This report describes the physics, code formulations, and numerics that are used in the TECATE (totally Eulerian code for anisotropic thermo-elasticity) and BREW (birefringent ray-tracing of electromagnetic waves) codes for laser design. These codes resolve thermal, stress, and birefringent optical effects in 3-D stationary solid-state systems. This suite of three constituent codes is a package referred to as LASRPAK.
Date: July 20, 1994
Creator: Gelinas, R. J.; Doss, S. K. & Nelson, R. G.
Partner: UNT Libraries Government Documents Department
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A 3-D Vortex Code for Parachute Flow Predictions: VIPAR Version 1.0

Description: This report describes a 3-D fluid mechanics code for predicting flow past bluff bodies whose surfaces can be assumed to be made up of shell elements that are simply connected. Version 1.0 of the VIPAR code (Vortex Inflation PARachute code) is described herein. This version contains several first order algorithms that we are in the process of replacing with higher order ones. These enhancements will appear in the next version of VIPAR. The present code contains a motion generator that can be used to produce a large class of rigid body motions. The present code has also been fully coupled to a structural dynamics code in which the geometry undergoes large time dependent deformations. Initial surface geometry is generated from triangular shell elements using a code such as Patran and is written into an ExodusII database file for subsequent input into VIPAR. Surface and wake variable information is output into two ExodusII files that can be post processed and viewed using software such as EnSight{trademark}.
Date: July 1, 2002
Creator: Strickland, James H.; Homicz, Gregory F.; Porter, Vicki L. & Gossler, Albert A.
Partner: UNT Libraries Government Documents Department
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5-kWe Reactor Thermoelectric System: Summary

Description: This report documents the systems and component requirements, design approaches, and performance and design characteristics for the 5-kwe system.
Date: July 27, 1973
Creator: Van Osdol, J. H.
Partner: UNT Libraries Government Documents Department
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8. Innovative Technologies: Two-Phase Heat Transfer in Water-Based Nanofluids for Nuclear Applications Final Report

Description: Abstract Nanofluids are colloidal dispersions of nanoparticles in water. Many studies have reported very significant enhancement (up to 200%) of the Critical Heat Flux (CHF) in pool boiling of nanofluids (You et al. 2003, Vassallo et al. 2004, Bang and Chang 2005, Kim et al. 2006, Kim et al. 2007). These observations have generated considerable interest in nanofluids as potential coolants for more compact and efficient thermal management systems. Potential Light Water Reactor applications include the primary coolant, safety systems and severe accident management strategies, as reported in other papers (Buongiorno et al. 2008 and 2009). However, the situation of interest in reactor applications is often flow boiling, for which no nanofluid data have been reported so far. In this project we investigated the potential of nanofluids to enhance CHF in flow boiling. Subcooled flow boiling heat transfer and CHF experiments were performed with low concentrations of alumina, zinc oxide, and diamond nanoparticles in water (≤ 0.1 % by volume) at atmospheric pressure. It was found that for comparable test conditions the values of the nanofluid and water heat transfer coefficient (HTC) are similar (within 20%). The HTC increased with mass flux and heat flux for water and nanofluids alike, as expected in flow boiling. The CHF tests were conducted at 0.1 MPa and at three different mass fluxes (1500, 2000, 2500 kg/m2s) under subcooled conditions. The maximum CHF enhancement was 53%, 53% and 38% for alumina, zinc oxide and diamond, respectively, always obtained at the highest mass flux. A post-mortem analysis of the boiling surface reveals that its morphology is altered by deposition of the particles during nanofluids boiling. A confocal-microscopy-based examination of the test section revealed that nanoparticles deposition not only changes the number of micro-cavities on the surface, but also the surface wettability. A simple model was …
Date: July 31, 2009
Creator: Buongiorno, Jacopo & Hu, Lin-wen
Partner: UNT Libraries Government Documents Department
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17 GHz High Gradient Accelerator Research

Description: This is a report on the MIT High Gradient Accelerator Research program which has included: Operation of the 17 GHz, 25 MeV MIT/Haimson Research Corp. electron accelerator at MIT, the highest frequency, stand-alone accelerator in the world; collaboration with members of the US High Gradient Collaboration, including the design and test of novel structures at SLAC at 11.4 GHz; the design, construction and testing of photonic bandgap structures, including metallic and dielectric structures; the investigation of the wakefields in novel structures; and the training of the next generation of graduate students and postdoctoral associates in accelerator physics.
Date: July 10, 2013
Creator: Temkin, Richard J. & Shapiro, Michael A.
Partner: UNT Libraries Government Documents Department
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20,000 KW Nuclear Power Plant Study for United States Atomic Energy Commission

Description: Introduction: In September of 156, Gilbert Associates, Inc., entered into a contract with the United States of America, acting through the United States Atomic Energy Commission, for the study and preliminary design of a nuclear power plant being considered for integration into a central station power system at an overseas site.
Date: July 7, 1957
Creator: Gilbert Associates, Inc.
Partner: UNT Libraries Government Documents Department
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20% Wind Energy by 2030

Description: This analysis explores one clearly defined scenario for providing 20% of our nations electricity demand with wind energy by 2030 and contrasts it to a scenario of no new wind power capacity.
Date: July 1, 2008
Partner: UNT Libraries Government Documents Department
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A 23-Group Neutron Thermalization Cross Section Library

Description: A set of 23-group neutron cross sections for use in the calculation of neutron thermalization and thermal neutron spectral effects in SNAP reactors is compiled. The sources and methods used to obtain the cross sections are described. (auth)
Date: July 15, 1963
Creator: Doctor, R. D. & Boling, M. A.
Partner: UNT Libraries Government Documents Department
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24 CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

Description: This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method of emplacing the array in a long, horizontal borehole. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: July 1, 2002
Creator: Westman, Erik C.
Partner: UNT Libraries Government Documents Department
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24-CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

Description: This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method for clamping the sensor once it is emplaced in the borehole. If the sensors (geophones) are not adequately coupled to the surrounding rock mass, the resulting data will be of very poor quality. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: July 1, 2002
Creator: Westman, Erik C.
Partner: UNT Libraries Government Documents Department
open access

24-CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

Description: This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method for orienting the sensor once it is emplaced in the borehole. If the sensors (geophones) do not have the same orientation, the data will be essentially worthless. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: July 1, 2002
Creator: Westman, Erik C.
Partner: UNT Libraries Government Documents Department
open access

24-CHANNEL GEOPHONE ARRAY FOR HORIZONTAL OR VERTICAL BOREHOLES

Description: This report describes the technical progress on a project to design and construct a multi-channel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the development of simple, robust, MSHA-acceptable clamping unit. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date: July 1, 2002
Creator: Westman, Erik C.
Partner: UNT Libraries Government Documents Department
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