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Development of Next Generation Multiphase Pipe Flow Prediction Tools (open access)

Development of Next Generation Multiphase Pipe Flow Prediction Tools

The developments of fields in deep waters (5000 ft and more) is a common occurrence. It is inevitable that production systems will operate under multiphase flow conditions (simultaneous flow of gas-oil-and water possibly along with sand, hydrates, and waxes). Multiphase flow prediction tools are essential for every phase of the hydrocarbon recovery from design to operation. The recovery from deep-waters poses special challenges and requires accurate multiphase flow predictive tools for several applications including the design and diagnostics of the production systems, separation of phases in horizontal wells, and multiphase separation (topside, seabed or bottom-hole). It is very crucial to any multiphase separation technique that is employed either at topside, seabed or bottom-hole to know inlet conditions such as the flow rates, flow patterns, and volume fractions of gas, oil and water coming into the separation devices. The overall objective was to develop a unified model for gas-oil-water three-phase flow in wells, flow lines, and pipelines to predict the flow characteristics such as flow patterns, phase distributions, and pressure gradient encountered during petroleum production at different flow conditions (pipe diameter and inclination, fluid properties and flow rates). The project was conducted in two periods. In Period 1 (four years), gas-oil-water …
Date: August 31, 2008
Creator: Flow, Tulsa Fluid
Object Type: Report
System: The UNT Digital Library
Calcium Carbonate Storage in Amorphous Form and Its Template-Induced Crystallization (open access)

Calcium Carbonate Storage in Amorphous Form and Its Template-Induced Crystallization

Calcium carbonate crystallization in organisms often occurs through the transformation from the amorphous precursor. It is believed that the amorphous phase could be temporarily stabilized and stored, until its templated transition to the crystalline form is induced. Here we develop a bio-inspired crystallization strategy that is based on the above mechanism. Amorphous calcium carbonate (ACC) spherulitic particles are formed and stabilized on a self-assembled monolayer (SAM) of hydroxy-terminated alkanethiols on Au surface. The ACC is stored as a reservoir for ions and is induced to crystallize on command by introducing a secondary surface that is functionalized with carboxylic acid-terminated SAM. This secondary surface acts as a template for oriented and patterned nucleation. Various oriented crystalline arrays and micropatterned films are formed. We also show that the ACC phase can be doped with foreign ions (e.g. Mg) and organic molecules (e.g. dyes) and that these dopants later function as growth modifiers of calcite crystals and become incorporated into the crystals during the transformation process of ACC to calcite. We believe that our strategy opens the way of using a stabilized amorphous phase as a versatile reservoir system that can be converted in a highly controlled fashion to a crystalline form upon …
Date: August 31, 2007
Creator: Han, T Y & Aizenberg, J
Object Type: Article
System: The UNT Digital Library
Industry-Government-University Cooperative Research Program for the Development of Structural Materials from Sulfate-Rich FGD Scrubber Sludge (open access)

Industry-Government-University Cooperative Research Program for the Development of Structural Materials from Sulfate-Rich FGD Scrubber Sludge

The main aim of our project was to develop technology, which converts flue gas desulfurization (FGD) sulfate-rich scrubber sludge into value-added decorative materials. Specifically, we were to establish technology for fabricating cost effective but marketable materials, like countertops and decorative tiles from the sludge. In addition, we were to explore the feasibility of forming siding material from the sludge. At the end of the project, we were to establish the potential of our products by generating 64 countertop pieces and 64 tiles of various colors. In pursuit of our above-mentioned goals, we conducted Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC) measurements of the binders and co-processed binders to identify their curing behavior. Using our 6-inch x 6-inch and 4-inch x 4-inch high pressure and high temperature hardened stainless steel dies, we developed procedures to fabricate countertop and decorative tile materials. The composites, fabricated from sulfate-rich scrubber sludge, were subjected to mechanical tests using a three-point bending machine and a dynamic mechanical analyzer (DMA). We compared our material's mechanical performance against commercially obtained countertops. We successfully established the procedures for the development of countertop and tile composites from scrubber sludge by mounting our materials on commercial boards. We fabricated …
Date: August 31, 2003
Creator: Malhotra, V. M. & Chugh, Y. P.
Object Type: Report
System: The UNT Digital Library
Supercement for Annular Seal and Long-Term Integrity in Deep, Hot Wells "DeepTrek" (open access)

Supercement for Annular Seal and Long-Term Integrity in Deep, Hot Wells "DeepTrek"

The purpose of this project is to formulate a 'Supercement' designed for improving the long-term sealing integrity in HPHT wells. Phase I concentrated on chemistry studies and screening tests to design and evaluate Portland-based, hybrid Portland, and non-Portland-based cement systems suitable for further scale-up testing. Phase II work concentrated on additional lab and field testing to reduce the candidate materials list to two systems, as well as scaleup activities aimed at verifying performance at the field scale. Phase II was extended thorough a proposal to develop additional testing capabilities aimed at quantifying cementing material properties and performance that were previously not possible. Phase III focused on bringing the material(s) developed in previous Phases to commercialization, through Field Trials, Cost/Benefit Analysis, and Technology Transfer. Extensive development and testing work throughout the project led to Phase III commercialization of two very different materials: (1) Highly-expansive cement (Portland-based), patent pending as 'PRESTRESSED CEMENT'; and (2) Epoxy Resin (non-Portland-based), patent pending. Trade name is Ultra Seal-R. In Phase III, work concentrated on application of the Supercement materials in various increasingly-challenging wells. Previous testing revealed that PRESTRESSED CEMENT, when applied in weak or unconsolidated formations, tends to expand away from the central pipe, restricting the …
Date: August 31, 2007
Creator: Technologies, CSI
Object Type: Report
System: The UNT Digital Library
A Novel Treatment for Acid Mine Drainage Utilizing Reclaimed Limestone Residual (open access)

A Novel Treatment for Acid Mine Drainage Utilizing Reclaimed Limestone Residual

The viability of utilizing Reclaimed Limestone Residual (RLR) to remediate Acid Mine Drainage (AMD) was investigated. Physical and chemical characterization of RLR showed that it is composed of various minerals that contain significant quantities of limestone or calcium bearing compounds that can be exploited for acid neutralization. Acid Neutralization Potential (ANP) test results showed that RLR has a neutralization potential of approximately 83% as calcium carbonate (CaCO{sub 3}). Neutralization tests with most of the heavy metals associated with AMD showed removal efficiencies of over 99%. An unexpected benefit of utilizing RLR was the removal of hexavalent chromium Cr (VI) from the aqueous phase. Due to an elevation in pH by RLR most AMD heavy metals are removed from solution by precipitation as their metal hydroxides. Cr (VI) however is not removed by pH elevation and therefore subsequent ongoing tests to elucidate the mechanism responsible for this reaction were conducted.
Date: August 31, 2004
Creator: Moo-Young, Horace K. & Ochola, Charles E.
Object Type: Report
System: The UNT Digital Library
Optical alignment techniques for line-imaging velocity interferometry and line-imaging self-emulsion of targets at the National Ignition Facility (NIF) (open access)

Optical alignment techniques for line-imaging velocity interferometry and line-imaging self-emulsion of targets at the National Ignition Facility (NIF)

The National Ignition Facility (NIF) requires optical diagnostics for measuring shock velocities in shock physics experiments. The Velocity Interferometer System for Any Reflector (VISAR) measures shock velocities, shock breakout times, and emission of 1- to 5-mm targets at a location remote to the NIF target chamber. Three optical systems using the same vacuum chamber port each have a total track of 69 feet. All optical lenses are on kinematic mounts or sliding rails, enabling pointing accuracy of the optical axis to be checked. Counter-propagating laser beams (orange and red) align these diagnostics to a listing of tolerances. The orange alignment laser is introduced at the entrance to the two-level interferometer table and passes forward through the optical systems to the recording streak cameras. The red alignment laser is introduced in front of the recording streak cameras and passes in the reverse direction through all optical elements, out of the interferometer table, eventually reaching the target chamber center. Red laser wavelength is selected to be at the 50 percent reflection point of a special beamsplitter used to separate emission light from the Doppler-shifted interferometer light. Movable aperture cards, placed before and after lens groups, show the spread of alignments spots created …
Date: August 31, 2007
Creator: Robert M. Malone, Brent C. Frogget, Morris I. Kaufman, Thomas W. Tunnell, Robert L. Guyton, Imants P. Reinbachs, Phillip W. Watts, et al.
Object Type: Article
System: The UNT Digital Library
Mercuric Iodide Photocell Technology for Room Temperature Readout of Scintillators (open access)

Mercuric Iodide Photocell Technology for Room Temperature Readout of Scintillators

Mercuric iodide (HgI2) is a well known material for the direct detection of gamma rays; however, the largest volume achievable is limited by thickness of the detector, which needs to be a small fraction of the average trapping length for electrons. We are reporting here preliminary results in using HgI2 crystals to fabricate photocells used in the readout of various scintillators. The optical spectral response and efficiency of these photocells were measured and will be reported. Preliminary nuclear response from a HgI2 photocell that was optically matched to a Ce3+ :LaBr3 scintillator will also be presented and discussed. Further improvements will be sought by optimizing the transparent contact technology.
Date: August 31, 2007
Creator: al., Warnick Kernan et
Object Type: Article
System: The UNT Digital Library
Harsh-Environment Packaging for Downhole Gas and Oil Exploration (open access)

Harsh-Environment Packaging for Downhole Gas and Oil Exploration

This research into new packaging materials and methods for elevated temperatures and harsh environment electronics focused on gaining a basic understanding of current state-of-the-art in electronics packaging used in industry today, formulating the thermal-mechanical models of the material interactions and developing test structures to confirm these models. Discussions were initiated with the major General Electric (GE) businesses that currently sell into markets requiring high temperature electronics and packaging. They related the major modes of failure they encounter routinely and the hurdles needed to be overcome in order to improve the temperature specifications of these products. We consulted with our GE business partners about the reliability specifications and investigated specifications and guidelines that from IPC and the SAE body that is currently developing guidelines for electronics package reliability. Following this, a risk analysis was conducted for the program to identify the critical risks which need to be mitigated in order to demonstrate a flex-based packaging approach under these conditions. This process identified metal/polyimide adhesion, via reliability for flex substrates and high temperature interconnect as important technical areas for reliability improvement.
Date: August 31, 2007
Creator: Bansal, Shubhra; Cho, Junghyun; Durocher, Kevin; Kapusta, Chris; Knobloch, Aaron; Shaddock, David et al.
Object Type: Report
System: The UNT Digital Library
Expanding Conventional Seismic Stratigrphy into the Multicomponent Seismic Domain (open access)

Expanding Conventional Seismic Stratigrphy into the Multicomponent Seismic Domain

Multicomponent seismic data are composed of three independent vector-based seismic wave modes. These wave modes are, compressional mode (P), and shear modes SV and SH. The three modes are generated using three orthogonal source-displacement vectors and then recorded using three orthogonal vector sensors. The components travel through the earth at differing velocities and directions. The velocities of SH and SV as they travel through the subsurface differ by only a few percent, but the velocities of SV and SH (Vs) are appreciably lower than the P-wave velocity (Vp). The velocity ratio Vp/Vs varies by an order of magnitude in the earth from a value of 15 to 1.5 depending on the degree of sedimentary lithification. The data used in this study were acquired by nine-component (9C) vertical seismic profile (VSP), using three orthogonal vector sources. The 9C vertical seismic profile is capable of generating P-wave mode and the fundamental S-wave mode (SH-SH and SV-SV) directly at the source station and permits the basic components of elastic wavefield (P, SH-SH and SV-SV) to be separated from one another for the purposes of imaging. Analysis and interpretations of data from the study area show that incident full-elastic seismic wavefield is capable of …
Date: August 31, 2008
Creator: Aluka, Innocent J.
Object Type: Report
System: The UNT Digital Library
Michrochannel plate for position sensitive alpha particle detection (open access)

Michrochannel plate for position sensitive alpha particle detection

This paper will describe the use of a microchannel plate (MCP) as the associated particle detector on a sealed tube neutron generator. The generator produces neutrons and associated alpha particles for use as a probe to locate and identify hidden explosives in associated particle imaging (API). The MCP measures the position in two dimensions and precise timing of the incident alpha particle, information which is then used to calculate the emission time and direction of the corresponding neutron. The MCP replaces the position-sensitive photomultipler tube (PSPMT) which, until recently, had been the only detector available for measuring position and timing for alpha particles in neutron generator applications. Where the PSPMT uses charge division for generating position information, a process that requires a first order correction to each pulse, the MCP uses delay-line timing, which requires no correction. The result is a device with an order of magnitude improvement in both position resolution and timing compared to the PSPMT. Hardware and software development and the measurements made to characterize the MCP for API applications are described.
Date: August 31, 2007
Creator: Tinsley, Paul Hurley and James
Object Type: Article
System: The UNT Digital Library
Final Report for Fractionation and Separation of Polydisperse Nanoparticles into Distinct Monodisperse Fractions Using CO2 Expanded Liquids (open access)

Final Report for Fractionation and Separation of Polydisperse Nanoparticles into Distinct Monodisperse Fractions Using CO2 Expanded Liquids

The overall objective of this project was to facilitate efficient fractionation and separation of polydisperse metal nanoparticle populations into distinct monodisperse fractions using the tunable solvent properties of gas expanded liquids. Specifically, the dispersibility of ligand-stabilized nanoparticles in an organic solution was controlled by altering the ligand-solvent interaction (solvation) by the addition of carbon dioxide (CO{sub 2}) gas as an antisolvent (thereby tailoring the bulk solvent strength) in a custom high pressure apparatus developed in our lab. This was accomplished by adjusting the CO{sub 2} pressure over the liquid dispersion, resulting in a simple means of tuning the nanoparticle precipitation by size. Overall, this work utilized the highly tunable solvent properties of organic/CO{sub 2} solvent mixtures to selectively size-separate dispersions of polydisperse nanoparticles (ranging from 1 to 20 nm in size) into monodisperse fractions ({+-}1nm). Specifically, three primary tasks were performed to meet the overall objective. Task 1 involved the investigation of the effects of various operating parameters (such as temperature, pressure, ligand length and ligand type) on the efficiency of separation and fractionation of Ag nanoparticles. In addition, a thermodynamic interaction energy model was developed to predict the dispersibility of different sized nanoparticles in the gas expanded liquids at …
Date: August 31, 2007
Creator: Roberts, Chistopher
Object Type: Report
System: The UNT Digital Library
H(curl) Auxiliary Mesh Preconditioning (open access)

H(curl) Auxiliary Mesh Preconditioning

This paper analyzes a two-level preconditioning scheme for H(curl) bilinear forms. The scheme utilizes an auxiliary problem on a related mesh that is more amenable for constructing optimal order multigrid methods. More specifically, we analyze the case when the auxiliary mesh only approximately covers the original domain. The latter assumption is important since it allows for easy construction of nested multilevel spaces on regular auxiliary meshes. Numerical experiments in both two and three space dimensions illustrate the optimal performance of the method.
Date: August 31, 2006
Creator: Kolev, T V; Pasciak, J E & Vassilevski, P S
Object Type: Article
System: The UNT Digital Library
Bridging the Pressure Gap in Water and Hydroxyl Chemistry on MetalSurfaces: the Cu(110) case (open access)

Bridging the Pressure Gap in Water and Hydroxyl Chemistry on MetalSurfaces: the Cu(110) case

None
Date: August 31, 2007
Creator: Andersson, K.; Ketteler, G.; Hendrik, B.; Yamamoto, S.; Ogasawara, H.; Pettersson, L.G.M. et al.
Object Type: Article
System: The UNT Digital Library
A Framework to Design and Optimize Chemical Flooding Processes (open access)

A Framework to Design and Optimize Chemical Flooding Processes

The goal of this proposed research is to provide an efficient and user friendly simulation framework for screening and optimizing chemical/microbial enhanced oil recovery processes. The framework will include (1) a user friendly interface to identify the variables that have the most impact on oil recovery using the concept of experimental design and response surface maps, (2) UTCHEM reservoir simulator to perform the numerical simulations, and (3) an economic model that automatically imports the simulation production data to evaluate the profitability of a particular design. Such a reservoir simulation framework is not currently available to the oil industry. The objectives of Task 1 are to develop three primary modules representing reservoir, chemical, and well data. The modules will be interfaced with an already available experimental design model. The objective of the Task 2 is to incorporate UTCHEM reservoir simulator and the modules with the strategic variables and developing the response surface maps to identify the significant variables from each module. The objective of the Task 3 is to develop the economic model designed specifically for the chemical processes targeted in this proposal and interface the economic model with UTCHEM production output. Task 4 is on the validation of the framework …
Date: August 31, 2006
Creator: Delshad, Mojdeh; Pope, Gary A. & Sepehrnoori, Kamy
Object Type: Report
System: The UNT Digital Library
Mathematically Reduced Chemical Reaction Mechanism Using Neural Networks (open access)

Mathematically Reduced Chemical Reaction Mechanism Using Neural Networks

This is the final technical report for the project titled 'Mathematically Reduced Chemical Reaction Mechanism Using Neural Networks'. The aim of the project was to develop an efficient chemistry model for combustion simulations. The reduced chemistry model was developed mathematically without the need of having extensive knowledge of the chemistry involved. To aid in the development of the model, Neural Networks (NN) was used via a new network topology known as Non-linear Principal Components Analysis (NPCA). A commonly used Multilayer Perceptron Neural Network (MLP-NN) was modified to implement NPCA-NN. The training rate of NPCA-NN was improved with the GEneralized Regression Neural Network (GRNN) based on kernel smoothing techniques. Kernel smoothing provides a simple way of finding structure in data set without the imposition of a parametric model. The trajectory data of the reaction mechanism was generated based on the optimization techniques of genetic algorithm (GA). The NPCA-NN algorithm was then used for the reduction of Dimethyl Ether (DME) mechanism. DME is a recently discovered fuel made from natural gas, (and other feedstock such as coal, biomass, and urban wastes) which can be used in compression ignition engines as a substitute for diesel. An in-house two-dimensional Computational Fluid Dynamics (CFD) code …
Date: August 31, 2007
Creator: Huque, Ziaul
Object Type: Report
System: The UNT Digital Library
Laser coupling to reduced-scale targets at NIF Early Light (open access)

Laser coupling to reduced-scale targets at NIF Early Light

Deposition of maximum laser energy into a small, high-Z enclosure in a short laser pulse creates a hot environment. Such targets were recently included in an experimental campaign using the first four of the 192 beams of the National Ignition Facility [J. A. Paisner, E. M. Campbell, and W. J. Hogan, Fusion Technology 26, 755 (1994)], under construction at the University of California Lawrence Livermore National Laboratory. These targets demonstrate good laser coupling, reaching a radiation temperature of 340 eV. In addition, the Raman backscatter spectrum contains features consistent with Brillouin backscatter of Raman forward scatter [A. B. Langdon and D. E. Hinkel, Physical Review Letters 89, 015003 (2002)]. Also, NIF Early Light diagnostics indicate that 20% of the direct backscatter from these reduced-scale targets is in the polarization orthogonal to that of the incident light.
Date: August 31, 2005
Creator: Hinkel, D. E.; Schneider, M. B.; Young, B. K.; Holder, J. P.; Langdon, A. B.; Baldis, H. A. et al.
Object Type: Article
System: The UNT Digital Library
Computational Chemistry-Based Identification of Ultra-Low Temperature Water-Gas-Shift Catalysts (open access)

Computational Chemistry-Based Identification of Ultra-Low Temperature Water-Gas-Shift Catalysts

The current work seeks to identify novel, catalytically-active, stable, poison-resistant LWGS catalysts that retain the superior activity typical of conventional Cu catalysts but can be operated at similar or lower temperatures. A database for the Binding Energies (BEs) of the LWGS relevant species, namely CO, O and OH on the most-stable, close-packed facets of a set of 17 catalytically relevant transition metals was established. This BE data and a database of previously established segregation energies was utilized to predict the stability of bimetallic NSAs that could be synthesized by combinations of the 17 parent transition metals. NSAs that were potentially stable both in vacuo and under the influence of strong-binding WGS intermediates were then selected for adsorption studies. A set of 40 NSAs were identified that satisfied all three screener criteria and the binding energies of CO, O and OH were calculated on a set of 66, 43 and 79 NSA candidates respectively. Several NSAs were found that bound intermediates weaker than the monometallic catalysts and were thus potentially poison-resistant. Finally, kinetic studies were performed and resulted in the discovery of a specific NSA-based bimetallic catalyst Cu/Pt that is potentially a promising LWGS catalyst. This stable Cu/Pt subsurface alloy is …
Date: August 31, 2008
Creator: Mavrikakis, Manos
Object Type: Report
System: The UNT Digital Library
Modeling NIF Experimental Designs with Adaptive Mesh Refinement and Lagrangian Hydrodynamics (open access)

Modeling NIF Experimental Designs with Adaptive Mesh Refinement and Lagrangian Hydrodynamics

Incorporation of adaptive mesh refinement (AMR) into Lagrangian hydrodynamics algorithms allows for the creation of a highly powerful simulation tool effective for complex target designs with three-dimensional structure. We are developing an advanced modeling tool that includes AMR and traditional arbitrary Lagrangian-Eulerian (ALE) techniques. Our goal is the accurate prediction of vaporization, disintegration and fragmentation in National Ignition Facility (NIF) experimental target elements. Although our focus is on minimizing the generation of shrapnel in target designs and protecting the optics, the general techniques are applicable to modern advanced targets that include three-dimensional effects such as those associated with capsule fill tubes. Several essential computations in ordinary radiation hydrodynamics need to be redesigned in order to allow for AMR to work well with ALE, including algorithms associated with radiation transport. Additionally, for our goal of predicting fragmentation, we include elastic/plastic flow into our computations. We discuss the integration of these effects into a new ALE-AMR simulation code. Applications of this newly developed modeling tool as well as traditional ALE simulations in two and three dimensions are applied to NIF early-light target designs.
Date: August 31, 2005
Creator: Koniges, A E; Anderson, R W; Wang, P; Gunney, B N; Becker, R; Eder, D C et al.
Object Type: Article
System: The UNT Digital Library
LLNL Submissions to US ITER Project Office Request for Expression of Interest (open access)

LLNL Submissions to US ITER Project Office Request for Expression of Interest

None
Date: August 31, 2005
Creator: Correll, D L
Object Type: Report
System: The UNT Digital Library
Supercement for Annular Seal and Long-Term Integrity in Deep, Hot Wells "Deep Trek" (open access)

Supercement for Annular Seal and Long-Term Integrity in Deep, Hot Wells "Deep Trek"

The purpose of this project is to formulate a ''Supercement'' designed for improving the long-term sealing integrity in HPHT wells. Phase I concentrated on chemistry studies and screening tests to design and evaluate Portland-based, hybrid Portland, and non-Portland-based cement systems suitable for further scale-up testing. Phase II work concentrated on additional lab and field testing to reduce the candidate materials list to two systems, as well as scale up activities aimed at verifying performance at the field scale. Phase II was extended thorough a proposal to develop additional testing capabilities aimed at quantifying cementing material properties and performance that were previously not possible. Two materials are being taken into Phase III for field testing and commercialization: {lg_bullet} Highly-expansive cement (Portland-based), patent pending as ''Pre-Stressed Cement'' {lg_bullet} Epoxy Resin (non-Portland-based), patent pending In Phase II, significant effort was expended on scaling up the processes for handling resin in the field, as it is quite different than conventional Portland-based cements in mixing, personnel protection, and cleanup. Through this effort, over fifty (50) field jobs were done at a variety of temperatures and depths, most with excellent results. Large-scale field testing was less relevant with Pre-stressed Cement, because the materials and surface processes …
Date: August 31, 2005
Creator: Edgley, Kevin D.; Sabins, Fred L. & Watters, Larry T.
Object Type: Report
System: The UNT Digital Library
Tariffs Can Be Structured to Encourage Photovoltaic Energy (open access)

Tariffs Can Be Structured to Encourage Photovoltaic Energy

The solar power market is growing at a quickening pace, fueled by an array of national and local initiatives and policies aimed at improving the value proposition of customer-sited photovoltaic (PV) systems. Though these policies take many forms, they commonly include up-front capital cost rebates or ongoing production incentives, supplemented by net metering requirements to ensure that customer-sited PV systems offset the full retail rate of the customer-hosts. Somewhat less recognized is the role of retail rate design, beyond net metering, on the customer-economics of grid-connected PV. Over the life of a PV system, utility bill savings represent a substantial portion of the overall economic value received by the customer. At the same time, the design of retail electricity rates, particularly for commercial and industrial customers, can vary quite substantially. Understanding how specific differences in rate design affect the value of customer-sited PV is therefore essential to supporting the continued growth of this market.
Date: August 31, 2008
Creator: Wiser, Ryan; Mills, Andrew; Barbose, Galen & Golove, William
Object Type: Article
System: The UNT Digital Library
Improving Paper Machine Efficiency/Productivity through On-line Control (open access)

Improving Paper Machine Efficiency/Productivity through On-line Control

This project involves implementing a new technology, microforming, in a headbox to produce an isotropic sheet with significant reductions in the MD/CD stiffness ratio (increasing CD specific STFI) and improved sheet uniformity. Microforming involves generating axial vorticity (i.e., swirl) prior to the converging nozzle of the headbox by retrofitting an existing tube block with swirl generation devices referred to as Vortigen system. The Vortigen system developed in this project is a retrofit technology to a hydraulic headbox tube block. The tubes in the tube block are re-designed to generate axial vorticity (or swirl) in the tubes. This type of flow results in higher intensity small-scale turbulence in the forming jet at the slice. The net effect, as demonstrated in pilot and commercial trials, is improvement in formation and surface smoothness, lower MD/CD tensile ratio, and consequently, higher CD strength properties such as CD STFI, Ring Crush and tensile or breaking length. The objective of this project is to implement microforming by developing the retrofit technology for generation and on-line control of axial vorticity in the tubes to optimize turbulent scale and intensity, and consequently, fiber network structure properties in the sheet. This technology results in significant improvements in the performance …
Date: August 31, 2007
Creator: Aidun, Cyrus K
Object Type: Report
System: The UNT Digital Library
Field Deployable Gamma Radiation Detectors for DHS Use (open access)

Field Deployable Gamma Radiation Detectors for DHS Use

Recently, the U.S. Department of Homeland Security (DHS) has integrated all nuclear detection research, development, testing, evaluation, acquisition, and operational support into a single office: the Domestic Nuclear Detection Office (DNDO). The DNDO has specific requirements set for all commercial and government off-the-shelf radiation detection equipment and data acquisition systems. This article would investigate several recent developments in field deployable gamma radiation detectors that are attempting to meet the DNDO specifications. Commercially available, transportable, handheld radio isotope identification devices (RIID) are inadequate for DHS’s requirements in terms of sensitivity, resolution, response time and reach back capability. The leading commercial vendor manufacturing handheld gamma spectrometer in the United States is Thermo Electron Corporation. Thermo Electron’s identiFINDER™, which primarily uses sodium iodide crystals (3.18-cm x 2.54-cm cylinders) as gamma detector, has a Full-Width-at-Half-Maximum energy resolution of 7 percent at 662 keV. Thermo Electron has just recently come up with a reach-back capability patented as RadReachBack™ that enables emergency personnel to obtain real-time technical analysis of radiation samples they find in the field. The current project has the goal to build a prototype handheld gamma spectrometer, equipped with a digital camera and an embedded cell phone to be used as an RIID with …
Date: August 31, 2007
Creator: Mukhopadhyay, Sanjoy
Object Type: Article
System: The UNT Digital Library
A National Collaboratory to Advance the Science of High Temperature Plasma Physics for Magnetic Fusion (open access)

A National Collaboratory to Advance the Science of High Temperature Plasma Physics for Magnetic Fusion

This report summarizes the work of the National Fusion Collaboratory (NFC) Project funded by the United States Department of Energy (DOE) under the Scientific Discovery through Advanced Computing Program (SciDAC) to develop a persistent infrastructure to enable scientific collaboration for magnetic fusion research. A five year project that was initiated in 2001, it built on the past collaborative work performed within the U.S. fusion community and added the component of computer science research done with the USDOE Office of Science, Office of Advanced Scientific Computer Research. The project was a collaboration itself uniting fusion scientists from General Atomics, MIT, and PPPL and computer scientists from ANL, LBNL, Princeton University, and the University of Utah to form a coordinated team. The group leveraged existing computer science technology where possible and extended or created new capabilities where required. Developing a reliable energy system that is economically and environmentally sustainable is the long-term goal of Fusion Energy Science (FES) research. In the U.S., FES experimental research is centered at three large facilities with a replacement value of over $1B. As these experiments have increased in size and complexity, there has been a concurrent growth in the number and importance of collaborations among large …
Date: August 31, 2006
Creator: Schissel, D. P.; Abla, G.; Burruss, J. R.; Feibush, E.; Fredian, T. W.; Goode, M. M. et al.
Object Type: Report
System: The UNT Digital Library