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Experimental Investigation and High Resolution Simulation of In-Situ Combustion Processes

Description: This final technical report describes work performed for the project 'Experimental Investigation and High Resolution Numerical Simulator of In-Situ Combustion Processes', DE-FC26-03NT15405. In summary, this work improved our understanding of in-situ combustion (ISC) process physics and oil recovery. This understanding was translated into improved conceptual models and a suite of software algorithms that extended predictive capabilities. We pursued experimental, theoretical, and numerical tasks during the performance period. The specific project objectives were (i) identification, experimentally, of chemical additives/injectants that improve combustion performance and delineation of the physics of improved performance, (ii) establishment of a benchmark one-dimensional, experimental data set for verification of in-situ combustion dynamics computed by simulators, (iii) develop improved numerical methods that can be used to describe in-situ combustion more accurately, and (iv) to lay the underpinnings of a highly efficient, 3D, in-situ combustion simulator using adaptive mesh refinement techniques and parallelization. We believe that project goals were met and exceeded as discussed.
Date: April 30, 2008
Creator: Gerritsen, Margot & Kovscek, Tony
Partner: UNT Libraries Government Documents Department


Description: Executive Summary The materials science understanding of high rate low cost processes for Coated Conductor will benefit the application to power utilities for low loss energy transportation and power generation as well for DOD applications. The research in this program investigated several materials processing approaches that are new and original, and are not being investigated elsewhere. This work added to the understanding of the material science of high rate PVD growth of HTSC YBCO assisted by a liquid phase. A new process discovered uses amorphous glassy precursors which can be made at high rate under flexible conditions of temperature and oxygen, and later brought to conditions of oxygen partial pressure and temperature for rapid conversion to YBCO superconductor. Good critical current densities were found, but further effort is needed to optimize the vortex pinning using known artificial inclusions. A new discovery of the physics and materials science of vortex pinning in the HTSC system using Sm in place of Y came at growth at unusually low oxygen pressure resulting in clusters of a low or non superconducting phase within the nominal high temperature phase. The driving force for this during growth is new physics, perhaps due to the low oxygen. This has the potential for high current in large magnetic fields at low cost, applicable to motors, generators and transformers. The technical demands of this project were the motivation for the development of instrumentation that could be essential to eventual process scale up. These include atomic absorption based on tunable diode lasers for remote monitoring and control of evaporation sources (developed under DARPA support), and the utility of Fourier Transform Infrared Reflectivity (FTIR) for aid in the synthesis of complex thin film materials (purchased by a DURIP-AFOSR grant).
Date: April 14, 2009
Creator: Beasley, Malcolm R. & H.Hammond, Robert
Partner: UNT Libraries Government Documents Department

22nd Texas Symposium on Relativistic Astrophysics

Description: The XXII Texas Symposium on Relativistic Astrophysics, jointly organized by the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), the Stanford Linear Accelerator Center, and the Physics Department of Stanford University, was held on December 13-17, 2004. Following the tradition of past Texas Symposia the presentations emphasized recent developments in Cosmology, High Energy Astrophysics and the frontiers between these and Gravitation and Particle Physics. This Symposium was attended by more than 500 colleagues from a spectrum of disciplines mentioned above. There were 9 Plenary Sessions, 3 Parallel Sessions and 2 Poster Sessions held during the five-day program, with 76 oral and 240 poster presentations. These are now documented on CD and in the eConf proceedings archive. Funding of $15,000 received from the DOE under award DE-FG02-05ER41362 was used for expenses related to facility, local transportation and administrative expenses.
Date: April 1, 2005
Creator: Bloom, Elliott
Partner: UNT Libraries Government Documents Department

Monitoring Uranium Transformations Determined by the Evolution of Biogeochemical Processes: Design of Mixed Batch Reactor and Column Studies at Oak Ridge National Laboratory

Description: With funds provided by the US DOE, Argonne National Laboratory subcontracted the design of batch and column studies to a Stanford University team with field experience at the ORNL IFRC, Oak Ridge, TN. The contribution of the Stanford group ended in 2011 due to budget reduction in ANL. Over the funded research period, the Stanford research team characterized ORNL IFRC groundwater and sediments and set up microcosm reactors and columns at ANL to ensure that experiments were relevant to field conditions at Oak Ridge. The results of microcosm testing demonstrated that U(VI) in sediments was reduced to U(IV) with the addition of ethanol. The reduced products were not uraninite but were instead U(IV) complexes associated with Fe. Fe(III) in solid phase was only partially reduced. The Stanford team communicated with the ANL team members through email and conference calls and face to face at the annual ERSP PI meeting and national meetings.
Date: April 17, 2013
Creator: Criddle, Craig S. & Wu, Weimin
Partner: UNT Libraries Government Documents Department

Final Report for Department of Energy/EERE (for public release)

Description: Developing CIGS solar cells calls for the understanding of materials and processing in order to translate the record small efficiency to module and the strategy to produce thin cells for materials and processing saving. This project has exploited nanostructuring of CIG solar cells, including nanowires and nanotextured substrates. We showed that nanowires function as well-defined CIGS-CdS p-n junction for understanding the chemical fluctuation, defect formation interface and grain boundary behaviors and the effect of ion diffusion, which are important but complicated issues for solar cell fabrication. We have also demonstrated effective nanoscale photon management on nanotextured substrate to provide opportunity for thin CIGS solar cells. We also developed the scalable methods for producing such nanotextured substrates. The research output in this project helps advancing the CIGS solar cells and broadly other solar cell technologies in cost reduction per unit power.
Date: April 30, 2012
Creator: Cui, Yi
Partner: UNT Libraries Government Documents Department

Exploring Shared Memory Protocols in FLASH

Description: ABSTRACT The goal of this project was to improve the performance of large scientific and engineering applications through collaborative hardware and software mechanisms to manage the memory hierarchy of non-uniform memory access time (NUMA) shared-memory machines, as well as their component individual processors. In spite of the programming advantages of shared-memory platforms, obtaining good performance for large scientific and engineering applications on such machines can be challenging. Because communication between processors is managed implicitly by the hardware, rather than expressed by the programmer, application performance may suffer from unintended communication – communication that the programmer did not consider when developing his/her application. In this project, we developed and evaluated a collection of hardware, compiler, languages and performance monitoring tools to obtain high performance on scientific and engineering applications on NUMA platforms by managing communication through alternative coherence mechanisms. Alternative coherence mechanisms have often been discussed as a means for reducing unintended communication, although architecture implementations of such mechanisms are quite rare. This report describes an actual implementation of a set of coherence protocols that support coherent, non-coherent and write-update accesses for a CC-NUMA shared-memory architecture, the Stanford FLASH machine. Such an approach has the advantages of using alternative coherence only where it is beneficial, and also provides an evolutionary migration path for improving application performance. We present data on two computations, RandomAccess from the HPC Challenge benchmarks and a forward solver derived from LS-DYNA, showing the performance advantages of the alternative coherence mechanisms. For RandomAccess, the non-coherent and write-update versions can outperform the coherent version by factors of 5 and 2.5, respectively. In LS-DYNA, we obtain improvements of 18% on average using the non-coherent version. We also present data on the SpecOMP benchmarks, showing that the protocols have a modest overhead of less than 3% in applications where the alternative ...
Date: April 1, 2007
Creator: Horowitz, Mark; Kunz, Robert; Hall, Mary; Lucas, Robert & Chame, Jacqueline
Partner: UNT Libraries Government Documents Department

CDC and PIN-CMOS Developments for Large Optical Telescope.

Description: Higher quantum efficiency in near-IR, narrower point spread function and higher readout speed than with conventional sensors have been receiving increased emphasis in the development of CCDs and silicon PIN-CMOS sensors for use in large optical telescopes. Some key aspects in the development of such devices are reviewed.
Date: April 3, 2006
Creator: Radeka, V.
Partner: UNT Libraries Government Documents Department

Future Trends in Microelectronics - Impact on Detector Readout.

Description: Mainstream CMOS is now a well-established detector readout technology. We review technology scaling trends and limits, the implementation of analog circuits in digital CMOS processes, and radiation resistance. Emphasis is placed on the growing importance of power dissipation in ultra-scaled technologies.
Date: April 3, 2006
Creator: O'connor, P.
Partner: UNT Libraries Government Documents Department

Final Report on the Construction of the HERS Endstation, September 1, 1996 - October 31, 1998

Description: The construction of the HERS endstation was successfully completed. The resolution of the photoemission apparatus is better than 7meV. The angular resolution is +0.15 degrees. The system has a high precision sample manipulator w/ five-degrees of freedom and a temperature range from 10 - 450 degrees K. The sample transfer system allows transfer of a sample from atmosphere onto the crystal @ 5x10 in less than 2 hrs.
Date: April 3, 2000
Creator: Kellar, S.A. Dr. & Shen, Z.X.
Partner: UNT Libraries Government Documents Department

Scale-up of miscible flood processes for heterogeneous reservoirs. Final report

Description: Results of a wide-ranging investigation of the scaling of gas injection processes are reported. The research examines how the physical mechanisms at work during a gas injection project interact to determine process performance. In particular, the authors examine: the interactions of equilibrium phase behavior and two-phase flow that determine local displacement efficiency and minimum miscibility pressure, the combined effects of viscous fingering, gravity segregation and heterogeneity that control sweep efficiency in 2- and 3-dimensional porous media, the use of streamtube/streamline methods to create very efficient simulation technique for multiphase compositional displacements, the scaling of viscous, capillary and gravity forces for heterogeneous reservoirs, and the effects of the thin films and spreading behavior on three-phase flow. The following key results are documented: rigorous procedures for determination of minimum miscibility pressure (MMP) or minimum miscibility enrichment (MME) for miscibility have been developed for multicomponent systems; the complex dependence of MMP`s for nitrogen/methane floods on oil and injection gas composition observed experimentally is explained for the first time; the presence of layer-like heterogeneities strongly influences the interplay of gravity segregation and viscous fingering, as viscous fingers adapt to preferential flow paths and low permeability layers restrict vertical flow; streamtube/streamline simulation techniques are demonstrated for a variety of injection processes in 2 and 3 dimensions; quantitative scaling estimates for the transitions from capillary-dominated to gravity-dominated to viscous-dominated flows are reported; experimental results are given that demonstrate that high pressure CO{sub 2} can be used to generate low IFT gravity drainage in fractured reservoirs if fractures are suitably connected; and the effect of wetting and spreading behavior on three-phase flow is described. 209 refs.
Date: April 1, 1996
Creator: Orr, F.M. Jr.
Partner: UNT Libraries Government Documents Department

Lattice design for the high energy ring of the SLAC B-Factory (PEP-II)

Description: The design of the lattice for the High Energy Ring (HER) of the SLAC B-Factory has several special features, notably provision for octupole compensation of amplitude dependent tune shift effects and a beta-beat scheme for semi-local chromaticity correction. In the arcs adjacent to the interaction point (IP) the beta functions are enhanced to allow the use of non-interlaced sextupoles to compensate the chromaticity of the interaction region. A closed bump of beta {open_quotes}mismatch{close_quotes} is generated by two vertically focusing quadrupoles spaced 2 betatron wavelengths apart. The beta-beat has two advantages: it enhances the ratio between the horizontal and vertical beta functions at the sextupoles and, because of the locally higher beta function, allows weaker sextupoles to be used. The standard design uses a 60 degree/cell lattice but a 90 degree/cell lattice may also be used if lower emittances and momentum compaction factor are desired.
Date: April 1, 1995
Creator: Donald, M.H.R.; Cai, Y. & Irwin, J.
Partner: UNT Libraries Government Documents Department

X-ray standing wave study of the Bi/GaAs and Bi/GaP interfaces

Description: Interfaces are one of the most important elements determining the characteristics of electronic devices. Composite semiconductors, specifically the III-V family, are technologically attractive because of their mobility and optical properties, and also because they offer the possibility of engineering such properties as the size of the band gap. Nevertheless, Si has remained the most utilized semiconductor material, primarily because the fabrication of practical MOSFETs with III-V semiconductors remains elusive. Examples of such complex interfaces are the structures formed by one monolayer of Bi on the (110) surface of GaAs and GaP. While better matched Column V elements form epitaxial continuous monolayers on III-V semiconductor (110) surfaces, Bi is too large to accommodate on GaAs and GaP surfaces with long range order, and vacancies appear to allow relaxation. For the ideal systems, symmetry imposes the presence of only two nonequivalent adatom sites. However, for Bi/GaAs and Bi/GaP, more than two different sites are present because the position of Bi atoms next to a vacancy is not necessarily equivalent to that between other Bi atoms. The geometry of the Bi/GaAs and Bi/GaP systems was determined here by triangulating XSW results from three Bragg planes. A methodology was developed that provides an intrinsic check of the validity of assuming two sites for the overlayer structures. An experimental method was developed that allows the three reflections to be measured on the same sample, thus reducing the number of experimental variables, such as the degree of disorder. The traditional method of analysis was not accurate enough for this data, so a more reliable and faster method of data fitting was developed. A configuration used in the present work, which previously has been widely used, presents an intrinsic multireflection problem. This issue is discussed in depth, and the appropriate method is determined for analyzing the data ...
Date: April 1, 1994
Creator: Herrera-Gomez, A.
Partner: UNT Libraries Government Documents Department


Description: This technical progress report describes work performed from January 1 through March 31, 2003 for the project ''Heavy and Thermal Oil Recovery Production Mechanisms,'' DE-FC26-00BC15311. In this project, a broad spectrum of research is undertaken related to thermal and heavy-oil recovery. The research tools and techniques span from pore-level imaging of multiphase fluid flow to definition of reservoir-scale features through streamline-based history matching techniques. During this period, previous analysis of experimental data regarding multidimensional imbibition to obtain shape factors appropriate for dual-porosity simulation was verified by comparison among analytic, dual-porosity simulation, and fine-grid simulation. We continued to study the mechanisms by which oil is produced from fractured porous media at high pressure and high temperature. Temperature has a beneficial effect on recovery and reduces residual oil saturation. A new experiment was conducted on diatomite core. Significantly, we show that elevated temperature induces fines release in sandstone cores and this behavior may be linked to wettability. Our work in the area of primary production of heavy oil continues with field cores and crude oil. On the topic of reservoir definition, work continued on developing techniques that integrate production history into reservoir models using streamline-based properties.
Date: April 1, 2003
Creator: Kovscek, Anthony R.
Partner: UNT Libraries Government Documents Department


Description: Accurate simulation of in-situ combustion processes is computationally very challenging because the spatial and temporal scales over which the combustion process takes place are very small. In this sixth quarter of our DoE funded research, we continued the development of our new simulation tool which is based on an efficient Cartesian Adaptive Mesh Refinement technique. This methodology allows much higher grid densities to be used near typical fronts than current simulators. We improved the upscaling strategy on these grids, and derived an effective way to generate upscaled permeabilities that preserve local fluxes. We have started more in-depth research into splitting methods for stiff PDEs such as those found in in-situ combustion simulation. We will report on these new developments extensively in the next quarterly report. This quarterly report, we focus on experimental work. On the experimental side, we have fleshed out a mechanism of improved in-situ combustion with aqueous metallic salts using scanning electron microscopy (SEM) and the transport phenomenon of such additives through porous media. Based on the observations from SEM analysis, we propose cation exchange of metallic salts with clay as a mechanism to create activated sites that enhance combustion reactions between oil and oxygen. Moreover, the empirical ranking of the success of metallic ions as catalytic additives for in-situ combustion is interpreted as originating from three factors: cation replacing power, distribution of metallic additive adsorption sites, and cation catalytic power for oxidation and cracking of hydrocarbon.
Date: April 1, 2005
Creator: Gerritsen, Margot & Kovscek, Anthony R.
Partner: UNT Libraries Government Documents Department


Description: We have made reproducible scanning probes with high efficiency, and predictable and reproducible character-istics. We obtained good efficiency with dimensions well below the diffraction limit, so that rela-tively small laser powers in the milliwatt range can be used. For single frequency operation, only low power is necessary to obtain very high fields for the excitation of well-defined Raman scattering, and to work in a reflection mode with good scanning speeds; obtained predictable results with very high fields suitable for obtaining Raman scattering and two-photon scattering; made a scanning probe mounted on a micromachined cantilever to obtain high definition reflection mode images that can be scanned rapidly;and observed Raman scattering using bowtie antennas with CW excitation.
Date: April 30, 2005
Creator: KINO, G.S. & MOERNER, W.E.
Partner: UNT Libraries Government Documents Department


Description: Our DOE project is one of the efforts comprising the Vertical Transport and Mixing Program of the Environmental Sciences Division of the Office of Biological and Environmental Research in Department of Energy. We used ARPS to simulate flow in the Salt Lake Valley. We simulated the physical processes more accurately so that we can better understand the physics of flow in complex terrain and its effects at larger scales. The simulations provided evidence that atmospheric forcing interacts with the Jordan Narrows, the Traverse Range and other complex mountain terrain at the south end of the Salt Lake Valley to produce lee rotors, hydraulic jumps and other effects. While we have successfully used ARPS to simulate VTMX 2000 flows, we have also used observed data to test the model and identify some of its weaknesses. Those are being addressed in a continuation project supported by DOE.
Date: April 11, 2005
Creator: Street, R. L.; Ludwig, F. L. & Chen, Y.
Partner: UNT Libraries Government Documents Department


Description: Accurate simulation of in-situ combustion processes is computationally very challenging because the spatial and temporal scales over which the combustion process takes place are very small. In this first quarterly report of our DoE funded research, we discuss the design of a new simulation tool based on an efficient Cartesian Adaptive Mesh Refinement technique that allows much higher grid densities to be used near typical fronts than current simulators. The formulation presented here for a first one-dimensional simulator will serve as the foundation for the development of a three-dimensional simulator that can handle realistic permeability heterogeneity. The development of the simulation tool will be supported by extensive laboratory experiments conducted to provide validation data, and to study effective variants of the combustion process. The preliminary investigation reported here shows how metallic salt additives can promote and sustain combustion by enhancing the oxidation and cracking of hydrocarbons.
Date: April 1, 2004
Creator: Gerritsen, Margot & Kovscek, Anthony R.
Partner: UNT Libraries Government Documents Department

Energy changes in transforming solids. Final report, January 31, 1991--January 31, 1995

Description: The following topics are discussed: A new thermodynamical theory of continuum damage mechanics capable of incorporating non-isothermal processes and of providing explicit expressions for the thermal dissipation during damage evolution; the advancement of the methodology of heterogenization to analyze elastic bodies with defects; and investigations of bonded dissimilar piezoelectric half-spaces.
Date: April 3, 1995
Creator: Herrmann, G. & Barnett, D.M.
Partner: UNT Libraries Government Documents Department