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Characterization of Turbiditic Oil Reservoirs Based on Geophysical Models of Their Formation

Description: Two aspects of the characterization of turbiditic oil reservoirs based on geophysical models of their formation are discussed in this report. First, we have developed a new, more accurate and computationally faster finite-element method (FEM) for simulating the flow and deposition of turbidity currents. Although a finite volume method had been presented and discussed in a previous report, it was discovered to be insufficient for our purposes of simulating turbidity flows. The new method allows variable grids near the regions of large deposition, which are of most interest, and numerically results in banded, sparse matrices that are much faster to solve. Examples of the success of the method are presented. In the second part of this report, we present and discuss a preliminary study on the feasibility of matching the results of a sediment transport model to field data. With the simulation of the turbidity current we can create an entire turbiditic deposit. This requires the initial conditions of the flow, such as the amount of sediment, the volume or flow rate of the current, etc, which are of course unavailable. This requires an estimate of the initial conditions of the flow, which can be determined from limited data from the deposit. We used the Excel optimization routine Solver to reproduce a one-dimensional algebraically simulated deposit with and without measurement noise. Results indicate that such matching is feasible, provided that the noise is below certain thresholds, dependent on the size of the deposit and the number data points constraining the parameter estimation.
Date: June 1, 2003
Creator: Bonnecaze, Roger T. & Lakshminarasimhan, Srivatsan
Partner: UNT Libraries Government Documents Department
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Solid State Energy Conversion Alliance Delphi SOFC

Description: The objective of Phase I under this project is to develop a 5 kW Solid Oxide Fuel Cell power system for a range of fuels and applications. During Phase I, the following will be accomplished: Develop and demonstrate technology transfer efforts on a 5 kW stationary distributed power generation system that incorporates steam reforming of natural gas with piped-in water (Demonstration System A); and Initiate development of a 5 kW system for later mass-market automotive auxiliary power unit application, which will incorporate Catalytic Partial Oxidation (CPO) reforming of gasoline, with anode exhaust gas injected into an ultra-lean burn internal combustion engine. This technical progress report covers work performed by Delphi from July through December 2002 under Department of Energy Cooperative Agreement DE-FC-02NT41246 for the 5 kW mass-market automotive (gasoline) auxiliary power unit. This report highlights technical results of the work performed under the following tasks for the automotive 5 kW system: Task 1--System Design and Integration; Task 2--Solid Oxide Fuel Cell Stack Developments; Task 3--Reformer Developments; Task 4--Development of Balance of Plant (BOP) Components; Task 5--Manufacturing Development (Privately Funded); Task 6--System Fabrication; and Task 7--System Testing.
Date: June 9, 2003
Creator: Shaffer, Steven; Kelly, Sean; Mukerjee, Subhasish; Schumann, David & Mieney, H. Skip
Partner: UNT Libraries Government Documents Department
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Correlation of point defects in CdZnTe with charge transport:application to room-temperature x-ray and gamma-ray. Final Technical Report

Description: The primary goal of this project has been to characterize and identify point defects (e.g., impurities, vacancies, vacancy-impurity complexes, etc.) in CdZnTe and determine the mechanisms by which these defects influence the carrier {mu}{tau}products. Special attention is given to the role of shallow donors, shallow acceptors, and deeper acceptors. There are two experimental focus areas in the project: (1) liquid-helium photoluminescence (PL) and PL excitation spectroscopy are used to identify and characterize donors and acceptors and to determine zinc molar fraction; and (2) electron paramagnetic resonance (EPR) and photoinduced EPR experiments are performed at liquid-helium temperature to identify paramagnetic point defects and to determine the concentration of these defects. Results from the two experimental focus areas are correlated with detector performance parameters (e.g., electron and hole {mu}{tau} products), crystal growth conditions, and microstructure analyses.
Date: June 25, 2003
Creator: Giles, Nancy C.
Partner: UNT Libraries Government Documents Department
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The Engineered Phytoremediation of Ionic and Methylmercury Pollution

Description: Our current specific objectives are to use transgenic plants to control the chemical species, electrochemical state, and above ground binding of mercury to (a) prevent methylmercury from entering the food-chain, (b) remove mercury from polluted sites, and (c) hyperaccumulate mercury in above ground tissues for later harvest.
Date: June 24, 2003
Creator: Meagher, Richard; Marshburn, Sarah; Heaton, Andrew; Zimer, Anne Marie & Rahman, Raoufa
Partner: UNT Libraries Government Documents Department
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OPTICAL FIBER SENSOR TECHNOLOGIES FOR EFFICIENT AND ECONOMICAL OIL RECOVERY

Description: Efficient recovery of petroleum reserves from existing oil wells has been proven to be difficult due to the lack of robust instrumentation that can accurately and reliably monitor processes in the downhole environment. Commercially available sensors for measurement of pressure, temperature, and fluid flow exhibit shortened lifetimes in the harsh downhole conditions, which are characterized by high pressures (up to 20 kpsi), temperatures up to 250 C, and exposure to chemically reactive fluids. Development of robust sensors that deliver continuous, real-time data on reservoir performance and petroleum flow pathways will facilitate application of advanced recovery technologies, including horizontal and multilateral wells. This is the final report for the four-year program ''Optical Fiber Sensor Technologies for Efficient and Economical Oil Recovery'', funded by the National Petroleum Technology Office of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech from October 1, 1999 to March 31, 2003. The main objective of this research program was to develop cost-effective, reliable optical fiber sensor instrumentation for real-time monitoring of various key parameters crucial to efficient and economical oil production. During the program, optical fiber sensors were demonstrated for the measurement of temperature, pressure, flow, and acoustic waves, including three successful field tests in the Chevron/Texaco oil fields in Coalinga, California, and at the world-class oil flow simulation facilities in Tulsa, Oklahoma. Research efforts included the design and fabrication of sensor probes, development of signal processing algorithms, construction of test systems, development and testing of strategies for the protection of optical fibers and sensors in the downhole environment, development of remote monitoring capabilities allowing real-time monitoring of the field test data from virtually anywhere in the world, and development of novel data processing techniques. Comprehensive testing was performed to …
Date: June 1, 2003
Creator: Wang, Anbo; Cooper, Kristie L. & Pickrell, Gary R.
Partner: UNT Libraries Government Documents Department
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Neutron Detection with a Cryogenic Spectrometer

Description: Cryogenic calorimeters are used for x-ray detection because of their exquisite energy resolution and have found application in x-ray astronomy, and the search for dark matter. These devices operate by detecting the heat pulse produced by ionization in an absorber cooled to temperatures below 1 K. Such temperatures are needed to lower the absorber's heat capacity to the point that the deposition of even a few eV results in a measurable temperature excursion. Typical absorbers for dark matter measurements are massive Si or Ge crystals, and, with Ge, have achieved a resolution of 650 eV at 10 keV. Chow, et al., report the measurement of the 60 keV emission from {sup 241}Am with 230 eV resolution using a superconducting tin absorber. Cunningham, et al., also using a superconducting tin absorber, have recently reported a four-fold improvement over Chow. With such results being reported from the x- and gamma-ray world it is natural to examine the possibilities for cryogenic neutron spectroscopy. Such a detector would operate by detecting the heat pulses caused by neutron capture and scattering. To date, {sup 6}LiF has been the absorber of choice because relatively large crystals can be grown, and it is an insulating material with low heat capacity. Silver reports the fabrication of a {sup 6}LiF spectrometer operating at 328 mK and achieving a resolution of 39 keV. De Marcillac reports the fabrication of a spectrometer operating at 80 mK and achieving 16 keV resolution when bombarded with 5 MeV alpha particles. In this paper, we report preliminary results with a TiB{sub 2} absorber exposed to thermal neutrons. In contrast to lithium, whose chemistry selects for LiF as the absorber, boron offers a rich chemistry from which to select materials with high boron content. We will discuss the considerations governing the choice of absorber material …
Date: June 23, 2003
Creator: Bell, Z. W.; Lamberti, V. E.; Carpenter, D. A. & Cristy, S. S.
Partner: UNT Libraries Government Documents Department
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Physical Property Models of Concentrated Cesium Eluate Solutions

Description: Major analytes expected to be present in the WTP cesium ion-exchange eluate solutions were identified from the available analytical data collected during radioactive bench-scale runs, and a test matrix of cesium eluate solutions was designed within the bounding concentration ranges of those major analytes. A computer model describing the semi-batch evaporation of cesium eluate solutions was built using the Environmental Simulation Program (ESP), licensed by OLI Systems, Inc., and was run to calculate the physical properties of each test matrix solution concentrated to the target endpoints of 80 percent and 100 percent bulk saturation. The calculated physical properties were then analyzed statistically and fitted into predetermined mathematical expressions for the bulk solubility, density, viscosity and heat capacity as a function of temperature and feed concentration of each species considered in the matrix. In addition, the volume reduction factor, which is defined as the ratio of total cumulative feed volume to that of the initial acid charge, was calculated and modeled for the 80 percent saturation case. The R2 of the resulting physical property models ranged from 0.89 to 0.99. Validation of these physical property models against the true experimental data was not part of the current work scope; instead, the results of model validation will be discussed later in another report, after all the necessary data for model validation have been collected and analyzed.
Date: June 18, 2003
Creator: Choi, A.S.
Partner: UNT Libraries Government Documents Department
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RESOURCE CHARACTERIZATION AND QUANTIFICATION OF NATURAL GAS-HYDRATE AND ASSOCIATED FREE-GAS ACCUMULATIONS IN THE PRUDHOE BAY - KUPARUK RIVER AREA ON THE NORTH SLOPE OF ALASKA

Description: Interim results are presented from the project designed to characterize, quantify, and determine the commercial feasibility of Alaska North Slope (ANS) gas-hydrate and associated free-gas resources in the Prudhoe Bay Unit (PBU), Kuparuk River Unit (KRU), and Milne Point Unit (MPU) areas. This collaborative research will provide practical input to reservoir and economic models, determine the technical feasibility of gas hydrate production, and influence future exploration and field extension of this potential ANS resource. The large magnitude of unconventional in-place gas (40-100 TCF) and conventional ANS gas commercialization evaluation creates industry-DOE alignment to assess this potential resource. This region uniquely combines known gas hydrate presence and existing production infrastructure. Many technical, economical, environmental, and safety issues require resolution before enabling gas hydrate commercial production. Gas hydrate energy resource potential has been studied for nearly three decades. However, this knowledge has not been applied to practical ANS gas hydrate resource development. ANS gas hydrate and associated free gas reservoirs are being studied to determine reservoir extent, stratigraphy, structure, continuity, quality, variability, and geophysical and petrophysical property distribution. Phase 1 will characterize reservoirs, lead to recoverable reserve and commercial potential estimates, and define procedures for gas hydrate drilling, data acquisition, completion, and production. Phases 2 and 3 will integrate well, core, log, and long-term production test data from additional wells, if justified by results from prior phases. The project could lead to future ANS gas hydrate pilot development. This project will help solve technical and economic issues to enable government and industry to make informed decisions regarding future commercialization of unconventional gas-hydrate resources.
Date: June 2, 2003
Creator: Hunter, Robert; Patil, Shirish; Casavant, Robert & Collett, Tim
Partner: UNT Libraries Government Documents Department
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Sludge Batch 3 Simulant Flowsheet Studies: Phase II SRAT/SME Results

Description: The Savannah River Technology Center (SRTC) - Immobilization Technology Section (ITS) was requested to perform simulant bench-scale flowsheet studies to qualify Sludge Batch 3 (SB3), the next sludge batch to be processed at the Defense Waste Processing Facility (DWPF). Simulant flowsheet runs have been performed for every sludge batch that has been qualified for DWPF processing to date. SB3 will consist primarily of Tank 7 sludge, but will also contain transfers from other tanks and processes at the SRS and other materials not considered typical for DWPF processing. Projections also indicate that SB3 may contain higher than previously observed levels of noble metals. Over the last year, SRTC has focused significant effort on studies to understand the behavior of SB3 and to evaluate any necessary process changes.
Date: June 17, 2003
Creator: Herman, C. C.
Partner: UNT Libraries Government Documents Department
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CH Packaging Operations Manual

Description: Introduction - This procedure provides instructions for assembling the following CH packaging payload: -Drum payload assembly -Standard Waste Box (SWB) assembly -Ten-Drum Overpack (TDOP).
Date: June 26, 2003
Creator: Westinghouse TRU Solutions LLC
Partner: UNT Libraries Government Documents Department
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Technetium Eluate Evaporation Solubility and Precipitation Performance

Description: The baseline flowsheet for low activity waste in the Hanford River Protection Project Waste Treatment Plant includes pretreatment of supernatant by removing technetium using ion exchange. The primary purpose of this work is validation of the predictions of the Tc eluate computer model.
Date: June 17, 2003
Creator: Johnson, J. D.
Partner: UNT Libraries Government Documents Department
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Probabilistic and numerical techniques in the study of statistical theories of turbulence. Final Technical Report

Description: In this research project we made fundamental advances in a number of problems arising in statistical equilibrium theories of turbulence. Here are the highlights. In most cases the mathematical analysis was supplemented by numerical calculations. (a) Maximum entropy principles. We analyzed in a unified framework the Miller-Robert continuum model of equilibrium states in an ideal fluid and a modification of that model due to Turkington. (b) Equivalence and nonequivalence of ensembles. We gave a complete analysis of the equivalence and nonequivalence of the microcanonical, canonical, and mixed ensembles at the level of equilibrium macrostates for a large class of models of turbulence. (c) Nonlinear stability of flows. We refined the well known Arnold stability theorems by proving the nonlinear stability of steady mean flows for the quasi-geostrophic potential vorticity equation in the case when the ensembles are nonequivalent. (d) Geophysical application. The theories developed in items (a), (b), and (c) were applied to predict the emergence and persistence of coherent structures in the active weather layer of the Jovian atmosphere. This is the first work in which sophisticated statistical theories are synthesized with actual observations data from the Voyager and Galileo space missions. (e) Nonlinear dispersive waves. For a class of nonlinear Schroedinger equations we demonstrated that the self-organization of solutions into a ground-state solitary wave immersed in fine-scale fluctuations is a relaxation into statistical equilibrium.
Date: June 9, 2003
Creator: Ellis, Richard S. & Turkington, B.
Partner: UNT Libraries Government Documents Department
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DE-FG03-01ER15237 Annual Progress Report 2003

Description: OAK B262 Annual report. We have investigated the thermodynamics of several nanoscale systems: Iron oxides: We have completed and published heat capacity and entropy data on goethite, lepidocrocite, and maghemite, as well as measured their heats of formation. We also have enthalpy of formation data for several poorly crystalline nanophase oxides (schwertmannite, ferrihydrite, and epsilon-Fe{sub 2}O{sub 3}). The next step is to measure thermodynamic properties as a function of surface area for several oxides. CoO-MgO: Thermochemical data for bulk samples are in press. Heat capacities have been measured for CoO, MgO, and some intermediate samples. Nanosized samples at several compositions are being prepared this summer. Thin films have been prepared and some solution calorimetry done, but additional sample preparation and characterization is needed. Hydration energetics: Our setups for gas adsorption calorimetry and water immersion calorimetry are being completed. We will test them with known materials (Al{sub 2}O{sub 3}, selected zeolites) and then proceed to work on TiO{sub 2}, Fe{sub 2}O{sub 3}, and zeolites.
Date: June 6, 2003
Creator: Navrotsky, Alexandra
Partner: UNT Libraries Government Documents Department
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ULTRA-LIGHTWEIGHT CEMENT

Description: The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report discusses testing that was performed for analyzing the alkali-silica reactivity of ULHS in cement slurries. Laboratory testing during the tenth quarter focused on evaluation of the alkali-silica reaction of eight different cement compositions, four of which contain ULHS. The original laboratory procedure for measuring set cement expansion resulted in test specimen erosion that was unacceptable. A different expansion procedure is being evaluated. This report provides a progress summary of ASR testing. The testing program initiated in November produced questionable initial results so the procedure was modified slightly and the testing was reinitiated. The results obtained with the modified procedure showed improvement over data obtained with the original procedure, but questionable data were obtained from several of the compositions. Additional modification of test procedures for compositions containing TXI Lightweight cement are being implemented and testing is ongoing.
Date: June 16, 2003
Creator: Sabins, Fred
Partner: UNT Libraries Government Documents Department
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SUNY beamline facilities at the National Synchrotron Light Source (Final Report)

Description: The DOE sponsored SUNY synchrotron project has involved close cooperation among faculty at several SUNY campuses. A large number of students and postdoctoral associates have participated in its operation which was centered at the X3 beamline of the National Synchrotron Light Source at Brookhaven National Laboratory. Four stations with capabilities for Small Angle Scattering, Single Crystal and Powder and Surface diffraction and EXAFS were designed and operated with capability to perform experiments at very low as well as elevated temperatures and under high vacuum. A large amount of cutting-edge science was performed at the facility, which in addition provided excellent training for students and postdoctoral scientists in the field.
Date: June 22, 2003
Creator: Coppens, Philip
Partner: UNT Libraries Government Documents Department
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Preliminary Modeling Results of Evaporated Tc-Eluate Physical Properties

Description: The original scope of this task was to develop mathematical expressions for the apparent solubility, density and heat capacity of concentrated technetium eluate solutions as a function of temperature and concentrations of significant analytes present in the as-received eluate feeds. The task scope was later expanded to develop additional correlations for viscosity and the volume reduction factor that can be achieved at 80 percent of the prescribed evaporation endpoint.
Date: June 3, 2003
Creator: Choi, A.S.
Partner: UNT Libraries Government Documents Department
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Impermeable Thin Al2O3 Overlay for TBC Protection From Sulfate and Vanadate Attack in Gas Turbines Quarterly Report

Description: In order to improve the hot corrosion resistance of yttria-stabilized zirconia (YSZ), an Al{sub 2}O{sub 3} overlay has been deposited on the surface of YSZ by electron-beam physical vapor deposition. Currently, hot corrosion tests were performed on the YSZ coatings with and without Al{sub 2}O{sub 3} overlay in molten salt mixture (Na{sub 2}SO{sub 4} + 0 {approx} 15wt%V{sub 2}O{sub 5}) at 950 C in order to investigate the effect of amount of vanadate on the hot corrosion behaviors. The results showed that the presence of in V{sub 2}O{sub 5} the molten salt exacerbates the degradation of both the monolithic YSZ coating and the composite YSZ/Al{sub 2}O{sub 3} system. The formation of low-melting Na{sub 2}O-V{sub 2}O{sub 5}-Al{sub 2}O{sub 3} liquid phase is responsible for degradation of the Al{sub 2}O{sub 3} overlay. The Al{sub 2}O{sub 3} overlay acts as a barrier against the infiltration of the molten salt into the YSZ coating during exposure to the molten salt mixture with <5wt% vanadate. In the next reporting period, we will use XPS and SIMS to study the interactions between alumina overlay and molten salt containing vanadate.
Date: June 10, 2003
Creator: Mao, Scott X.
Partner: UNT Libraries Government Documents Department
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Energetic Ion Behavior in the National Spherical Torus Experiment

Description: The National Spherical Torus Experiment (NSTX) is a low aspect ratio (R/a approximately equal to 1.3) device with auxiliary heating from neutral beam injection (NBI) and high harmonic fast wave (HHFW) heating. Typical NSTX parameters are R(sub)0 = 85 cm, a = 67 cm, I(sub)p less than or equal to 1.5 MA, B(sub)T = 0.3-0.6 T. Three co-directed deuterium neutral beam sources have injected P(sub)NB less than or equal to 6.2 MW at energies E(sub)b less than or equal to 100 keV. HHFW heating has delivered up to P(sub)RF approximately equal to 6 MW to deuterium and helium plasmas.
Date: June 26, 2003
Creator: Medley, S. S.; Bell, R. E.; Fredrickson, E. D. & Roquemore, A. L.
Partner: UNT Libraries Government Documents Department
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A preliminary comparative study of the electron-cloud effect for the PSR, ISIS, and the ESS

Description: We present preliminary electron-cloud simulation results for the Proton Storage Ring (PSR) at LANL, ISIS at RAL, and the European Spallation Source (ESS). For each storage ring, we simulate the build-up and dissipation of the electron cloud (EC) in a representative field-free section of the vacuum chamber. For all three cases, we choose the same residual gas temperature, secondary emission yield (SEY), and secondary emission spectrum. Other variables such as proton loss rate, bunch profile, intensity and energy, residual gas pressure and chamber geometry, are set at the corresponding values for each machine. Under these assumptions, we conclude that, of the three machines, the PSR is the most severely affected by the electron cloud effect (ECE), followed by the ESS, with ISIS a distant third. We illustrate a strong sensitivity of the ECE to the longitudinal bunch profile by choosing two different shapes for the case of the PSR, and a weak sensitivity to residual gas pressure. This preliminary study does not address the ECE in other regions of the machine, nor the beam instability that might arise from the EC.
Date: June 20, 2003
Creator: Furman, M. A. & Pivi, M. T. F.
Partner: UNT Libraries Government Documents Department
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High performance computing: Clusters, constellations, MPPs, and future directions

Description: Last year's paper by Bell and Gray [1] examined past trends in high performance computing and asserted likely future directions based on market forces. While many of the insights drawn from this perspective have merit and suggest elements governing likely future directions for HPC, there are a number of points put forth that we feel require further discussion and, in certain cases, suggest alternative, more likely views. One area of concern relates to the nature and use of key terms to describe and distinguish among classes of high end computing systems, in particular the authors use of ''cluster'' to relate to essentially all parallel computers derived through the integration of replicated components. The taxonomy implicit in their previous paper, while arguable and supported by some elements of our community, fails to provide the essential semantic discrimination critical to the effectiveness of descriptive terms as tools in managing the conceptual space of consideration. In this paper, we present a perspective that retains the descriptive richness while providing a unifying framework. A second area of discourse that calls for additional commentary is the likely future path of system evolution that will lead to effective and affordable Petaflops-scale computing including the future role of computer centers as facilities for supporting high performance computing environments. This paper addresses the key issues of taxonomy, future directions towards Petaflops computing, and the important role of computer centers in the 21st century.
Date: June 10, 2003
Creator: Dongarra, Jack; Sterling, Thomas; Simon, Horst & Strohmaier, Erich
Partner: UNT Libraries Government Documents Department
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GILA User's Manual

Description: GILA is a finite element code that has been developed specifically to attack the class of transient, incompressible, viscous, fluid dynamics problems that are predominant in the world that surrounds us. The purpose for this document is to provide sufficient information for an experienced analyst to use GILA in an effective way. The GILA User's Manual presents a technical outline of the governing equations for time-dependent incompressible flow, and the explicit and semi-implicit projection methods used in GILA to solve the equations. This manual also presents a brief overview of some of GILA's capabilities along with the keyword input syntax and sample problems.
Date: June 1, 2003
Creator: CHRISTON, MARK A.
Partner: UNT Libraries Government Documents Department
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A Thermoelastic Hydraulic Fracture Design Tool for Geothermal Reservoir Development

Description: Geothermal energy is recovered by circulating water through heat exchange areas within a hot rock mass. Geothermal reservoir rock masses generally consist of igneous and metamorphic rocks that have low matrix permeability. Therefore, cracks and fractures play a significant role in extraction of geothermal energy by providing the major pathways for fluid flow and heat exchange. Thus, knowledge of conditions leading to formation of fractures and fracture networks is of paramount importance. Furthermore, in the absence of natural fractures or adequate connectivity, artificial fracture are created in the reservoir using hydraulic fracturing. At times, the practice aims to create a number of parallel fractures connecting a pair of wells. Multiple fractures are preferred because of the large size necessary when using only a single fracture. Although the basic idea is rather simple, hydraulic fracturing is a complex process involving interactions of high pressure fluid injections with a stressed hot rock mass, mechanical interaction of induced fractures with existing natural fractures, and the spatial and temporal variations of in-situ stress. As a result it is necessary to develop tools that can be used to study these interactions as an integral part of a comprehensive approach to geothermal reservoir development, particularly enhanced geothermal systems. In response to this need we have set out to develop advanced thermo-mechanical models for design of artificial fractures and rock fracture research in geothermal reservoirs. These models consider the significant hydraulic and thermo-mechanical processes and their interaction with the in-situ stress state. Wellbore failure and fracture initiation is studied using a model that fully couples poro-mechanical and thermo-mechanical effects. The fracture propagation model is based on a complex variable and regular displacement discontinuity formulations. In the complex variable approach the displacement discontinuities are defined from the numerical solution of a complex hypersingular integral equation written for a …
Date: June 30, 2003
Creator: Ghassemi, Ahmad
Partner: UNT Libraries Government Documents Department
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