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Chemical Technology Division Unit Operations Section Monthly Progress Report, April 1962

Description: Bubble size measurements in the foam column showed that a spinnerette with 50 mu holes gave a nearly normal distribution of bubbles sizes while a coarse fritted glass gas sparger had a tail of large bubbles which did not fit the normal curve. A set of equations solvable by a finite difference technique are presented which completely describe the irreversible reaction rate of H/sub 2/ or CO with a fixed bed of CuO pellets. Radiation damage tests are in progress to evaluate plastics for the Trans… more
Date: October 1, 1962
Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Acoustic imaging of vapor bubbles through optically non-transparent media

Description: A preliminary investigation of the feasibility of acoustic imaging of vapor bubbles through optically nontransparent media is described. Measurements are reported showing the echo signals produced by air filled glass spheres of various sizes positioned in an aqueous medium as well as signals produced by actual vapor bubbles within a water filled steel pipe. In addition, the influence of the metallic wall thickness and material on the amplitude of the echo signals is investigated. Finally severa… more
Date: October 1, 1983
Creator: Kolbe, W.F.; Turko, B.T. & Leskovar, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of Rayleigh-Taylor Instability: Statistics on Rising Bubbles and Falling Spikes

Description: The analysis of coherent structures in Rayleigh-Taylor simulations is a challenging task as the lack of a precise definition of these structures is compounded by the massive size of the datasets. In an earlier work, we used techniques from image analysis to count these coherent structures in two high-resolution simulations, one a large-eddy simulation with 30 terabytes of analysis data, and the other a direct numerical simulation with 80 terabytes of analysis data. Our analysis indicated that t… more
Date: October 30, 2007
Creator: Kamath, C; Gezahegne, A & Miller, P
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dislocation-Radiation Obstacle Interactions: Developing Improved Mechanical Property Constitutive Models

Description: The objective of this program was to understand the interaction of dislocations with a wide range of obstacles commonly produced in materials under irradiation (dislocation loops, voids, helium bubbles, stacking fault tetrahedra and radiation-induced precipitates). The approach employed in this program combined multi-scale modeling and dynamic in-situ and static ex-situ transmission electron microscopy experiments.
Date: October 10, 2008
Creator: Robertson, Ian
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Graphical Representation of Temporal Data from Simulations

Description: The analysis of extremely large data sets is time-consuming and tedious. In this project, we create two tools, the Image Inspector and the Video Inspector, to aid in the automated analysis of 3D temporal data from simulations. Our problem is the 3-dimensional time varying data of the Rayleigh-Taylor instability in a fluid mix problem. We examine the bubble dynamics due to the acceleration of gravity in an initially perturbed interface between a heavier and lighter fluid. Through the use of Open… more
Date: October 13, 2005
Creator: Eder, E F & Harrison, C D
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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University/NETL Student Partnership Program

Description: The University/National Energy Technology Laboratory (NETL) Student Partnership Program stimulated basic and applied research in Energy and Environmental Science areas through NETL's Office of Science and Technology (OST). This Partnership Program supported the education of graduate students in Energy and Environmental Sciences, while fostering increased scientific interaction between NETL and the participating universities, by providing graduate student support for research at a NETL facility … more
Date: October 31, 2006
Creator: Holder, Gerald; Mathews, Jonathan; Wilson, Thomas; Chuang, Steven; Amon, Cristina; Ertekin, Turgay et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Progress in the Development of Compressible, Multiphase Flow Modeling Capability for Nuclear Reactor Flow Applications

Description: In nuclear reactor safety and optimization there are key issues that rely on in-depth understanding of basic two-phase flow phenomena with heat and mass transfer. Within the context of multiphase flows, two bubble-dynamic phenomena – boiling (heterogeneous) and flashing or cavitation (homogeneous boiling), with bubble collapse, are technologically very important to nuclear reactor systems. The main difference between boiling and flashing is that bubble growth (and collapse) in boiling is inhibi… more
Date: October 1, 2008
Creator: Berry, R. A.; Saurel, R.; Petitpas, F.; Daniel, E.; Metayer, O. Le; Gavrilyuk, S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Summary of Degas II performance at the US Strategic Petroleum Reserve Big Hill site.

Description: Crude oil stored at the US Strategic Petroleum Reserve (SPR) requires mitigation procedures to maintain oil vapor pressure within program delivery standards. Crude oil degasification is one effective method for lowering crude oil vapor pressure, and was implemented at the Big Hill SPR site from 2004-2006. Performance monitoring during and after degasification revealed a range of outcomes for caverns that had similar inventory and geometry. This report analyzed data from SPR degasification and d… more
Date: October 1, 2007
Creator: Rudeen, David K. (GRAM, Inc., Albuquerque, NM) & Lord, David L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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SPARC-90: A code for calculating fission product capture in suppression pools

Description: This report describes the technical bases and use of two updated versions of a computer code initially developed to serve as a tool for calculating aerosol particle retention in boiling water reactor (BWR) pressure suppression pools during severe accidents, SPARC-87 and SPARC-90. The most recent version is SPARC-90. The initial or prototype version (Owczarski, Postma, and Schreck 1985) was improved to include the following: rigorous treatment of local particle deposition velocities on the surfa… more
Date: October 1, 1991
Creator: Owczarski, P.C. & Burk, K.W. (Pacific Northwest Lab., Richland, WA (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Fast ultrasonic imaging in a liquid filled pipe

Description: A new method is described for the imaging of the interior of a liquid filled metallic pipe using acoustical techniques. The experimental system incorporates an array of 20 acoustical transducers and is capable of capturing the images of moving bubbles at a frame rate in excess of 300/s. The transducers are mounted circumferentially around the pipe. Each transducer is pulsed in sequence, and the echoes reflected from vapor bubbles in the interior are detected, digitized and processed by a comput… more
Date: October 1, 1985
Creator: Kolbe, W.F.; Turko, B.T. & Leskovar, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Kinetics of fission product release prior to fuel slumping

Description: This paper describes the primary physical/chemical models recently incorporated into a mechanistic code (FASTGRASS) for the estimation of fission product release from fuel, and compares predicted results with test data. The theory of noble gas behavior is discussed in relation to its effect on the release behavior of I, Cs, Te, Ba, and Sr. The behavior of these fission products in the presence of fuel liquefaction/dissolution and oxidation grain-growth phenomena is presented, as is the chemistr… more
Date: October 1, 1987
Creator: Rest, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal-hydraulic studies on molten core-concrete interactions

Description: This report discusses studies carried out in connection with light water power reactor accidents. Recent assessments have indicated that the consequences of molten-core concrete interactions dominate the considerations of severe accidents. The two areas of interest that have been investigated are interlayer heat and mass transfer and liquid-liquid boiling. Interlayer heat and mass transfer refers to processes that occur within a core melt between the stratified, immiscible phases of core oxides… more
Date: October 1, 1986
Creator: Greene, G.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Micromodel foam flow study

Description: Foams are often utilized as part of enhanced oil recovery techniques. This report presents the results of a micromodel foam flow study. Micromodels are valuable tools in uncovering capillary phenomena responsible for lamellae generation and coalescence during foam flow in porous media. Among the mechanisms observed are snap-off, weeping-flow breakup, and lamella division and leave behind. Coalescence mechanisms include dynamic capillary-pressure-induced lamella drainage and gas diffusion. These… more
Date: October 1, 1990
Creator: Chambers, K.T. & Radke, C.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Bubbles and their implications for laser-fusion

Description: Bubbles are concentrations of electromagnetic energy in the region of the critical density that force out the plasma to form a void. Since the critical density surface is cratered, absorption may be greater than a smooth surface since a larger area will be available for absorption and the reflected light will have a large probability of restriking the critical density. The distance between bubbles is several wavelengths and consequently they may encourage Rayleigh--Taylor instabilities. The thr… more
Date: October 28, 1975
Creator: Estabrook, K. G. & Valeo, E. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DETERMINATION OF HLW GLASS MELT RATE USING X-RAY COMPUTED TOMOGRAPHY

Description: The purpose of the high-level waste (HLW) glass melt rate study is two-fold: (1) to gain a better understanding of the impact of feed chemistry on melt rate through bench-scale testing, and (2) to develop a predictive tool for melt rate in support of the on-going frit development efforts for the Defense Waste Processing Facility (DWPF). In particular, the focus is on predicting relative melt rates, not the absolute melt rates, of various HLW glass formulations solely based on feed chemistry, i.… more
Date: October 6, 2011
Creator: Choi, A.; Miller, D. & Immel, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

NUMERICAL SIMULATION OF VORTEX BREAKDOWN

Description: Vortex breakdown is simulated by a three dimensional Lagrangian method using vortex filaments. The filaments are approximated by vortex elements and their velocity is computed by a Biot-Savart type law of interaction. The numerical calculations show the development of an axisymmetric bubble with a recirculation zone and resemble in many respects the results obtained in the physical experiments on vortex breakdown.
Date: October 1, 1978
Creator: Prete, Vincenza Del
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Properties of Trapped Electron Bunches in a Plasma Wakefield Accelerator

Description: Plasma-based accelerators use the propagation of a drive bunch through plasma to create large electric fields. Recent plasma wakefield accelerator (PWFA) experiments, carried out at the Stanford Linear Accelerator Center (SLAC), successfully doubled the energy for some of the 42 GeV drive bunch electrons in less than a meter; this feat would have required 3 km in the SLAC linac. This dissertation covers one phenomenon associated with the PWFA, electron trapping. Recently it was shown that PWFAs… more
Date: October 30, 2009
Creator: Kirby, Neil
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis and Measurement of Bubble Dynamics and Associated Flow Field in Subcooled Nucleate Boiling Flows

Description: In recent years, subooled nucleate boiling (SNB) has attrcted expanding research interest owing to the emergence of axial offset anomaly (AOA) or crud-induced power shigt (CIPS) in many operating US PWRs, which is an unexpected deviation in the core axial power distribution from the predicted power curves. Research indicates that the formation of the crud, which directly leads to AOA phenomena, results from the presence of the subcooled nucleate boiling, and is especially realted to bubble moti… more
Date: October 1, 2008
Creator: Jones, Barclay G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Crossing the mesoscale no-man<U+2019>s land via parallel kinetic Monte Carlo.

Description: The kinetic Monte Carlo method and its variants are powerful tools for modeling materials at the mesoscale, meaning at length and time scales in between the atomic and continuum. We have completed a 3 year LDRD project with the goal of developing a parallel kinetic Monte Carlo capability and applying it to materials modeling problems of interest to Sandia. In this report we give an overview of the methods and algorithms developed, and describe our new open-source code called SPPARKS, for Stocha… more
Date: October 1, 2009
Creator: Garcia Cardona, Cristina (San Diego State University); Webb, Edmund Blackburn, III; Wagner, Gregory John; Tikare, Veena; Holm, Elizabeth Ann; Plimpton, Steven James et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modeling of Gap Closure in Uranium-Zirconium Alloy Metal Fuel - A Test Problem

Description: Uranium based binary and ternary alloy fuel is a possible candidate for advanced fast spectrum reactors with long refueling intervals and reduced liner heat rating [1]. An important metal fuel issue that can impact the fuel performance is the fuel-cladding gap closure, and fuel axial growth. The dimensional change in the fuel during irradiation is due to a superposition of the thermal expansion of the fuel due to heating, volumetric changes due to possible phase transformations that occur durin… more
Date: October 1, 2009
Creator: Simunovic, Srdjan; Ott, Larry J.; Gorti, Sarma B.; Nukala, Phani K.; Radhakrishnan, Balasubramaniam & Turner, John A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement and Analysis of Gas Bubbles Near a Reference Electrode in Aqueous Solutions

Description: Bubble size distributions (BSDs) near a reference electrode (RE) in aqueous glycerol solutions of an electrolyte NaCl have been investigated under various gas superficial velocities (U{sub S}). BSD and voltage reading of the solution were measured by using a high-speed digital camera and a pH/voltage meter, respectively. The results show that bubble size (b) increases with liquid viscosity ({mu}{sub c}) and U{sub S}. Self-similarity is seen and can be described by the log-normal form of the con… more
Date: October 1, 2005
Creator: Phongikaroon, Supathorn; Herrmann, Steve; Li, Shelly & Simpson, Michael
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A physical description of fission product behavior fuels for advanced power reactors.

Description: The Global Nuclear Energy Partnership (GNEP) is considering a list of reactors and nuclear fuels as part of its chartered initiative. Because many of the candidate materials have not been explored experimentally under the conditions of interest, and in order to economize on program costs, analytical support in the form of combined first principle and mechanistic modeling is highly desirable. The present work is a compilation of mechanistic models developed in order to describe the fission produ… more
Date: October 18, 2007
Creator: Kaganas, G. & Rest, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Topical Report: Task 2.3 "Aphron Shell Hydrophobicity"

Description: Various methods were investigated to measure the oil-wetting character of transient bubbles under static and dynamic conditions, in order to determine the roles played by bubble and micellar agglomeration, coalescence and adhesion to mineral surfaces.
Date: October 28, 2004
Creator: Fosdick, Miranda & Growcock, Fred
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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