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3-D Reservoir and Stochastic Fracture Network Modeling for Enhanced Oil Recovery, Circle Ridge Phosphoria/Tensleep Reservoir, Wind River Reservation, Arapaho and Shoshone Tribes, Wyoming

Description: This report describes the results made in fulfillment of contract DE-FG26-00BC15190, ''3-D Reservoir and Stochastic Fracture Network Modeling for Enhanced Oil Recovery, Circle Ridge Phosphoria/Tensleep Reservoir, Wind River Reservation, Arapaho and Shoshone Tribes, Wyoming''. The goal of this project is to improve the recovery of oil from the Tensleep and Phosphoria Formations in Circle Ridge Oilfield, located on the Wind River Reservation in Wyoming, through an innovative integration of matrix characterization, structural reconstruction, and the characterization of the fracturing in the reservoir through the use of discrete fracture network models. Fields in which natural fractures dominate reservoir permeability, such as the Circle Ridge Field, often experience sub-optimal recovery when recovery processes are designed and implemented that do not take advantage of the fracture systems. For example, a conventional waterflood in a main structural block of the Field was implemented and later suspended due to unattractive results. It is estimated that somewhere less than 20% of the OOIP in the Circle Ridge Field have been recovered after more than 50 years' production. Marathon Oil Company identified the Circle Ridge Field as an attractive candidate for several advanced IOR processes that explicitly take advantage of the natural fracture system. These processes require knowledge of the distribution of matrix porosity, permeability and oil saturations; and understanding of where fracturing is likely to be well-developed or poorly developed; how the fracturing may compartmentalize the reservoir; and how smaller, relatively untested subthrust fault blocks may be connected to the main overthrust block. For this reason, the project focused on improving knowledge of the matrix properties, the fault block architecture and to develop a model that could be used to predict fracture intensity, orientation and fluid flow/connectivity properties. Knowledge of matrix properties was greatly extended by calibrating wireline logs from 113 wells with incomplete or older-vintage ...
Date: November 18, 2002
Creator: La Pointe, Paul; Hermanson, Jan; Parney, Robert; Eiben, Thorsten; Dunleavy, Mike; Steele, Ken et al.
Partner: UNT Libraries Government Documents Department

A 3-Dimensional discrete fracture network generator to examine fracture-matrix interaction using TOUGH2

Description: Water fluxes in unsaturated, fractured rock involve the physical processes occurring at fracture-matrix interfaces within fracture networks. Modeling these water fluxes using a discrete fracture network model is a complicated effort. Existing preprocessors for TOUGH2 are not suitable to generate grids for fracture networks with various orientations and inclinations. There are several 3-D discrete-fracture-network simulators for flow and transport, but most of them do not capture fracture-matrix interaction. We have developed a new 3-D discrete-fracture-network mesh generator, FRACMESH, to provide TOUGH2 with information about the fracture network configuration and fracture-matrix interactions. FRACMESH transforms a discrete fracture network into a 3 dimensional uniform mesh, in which fractures are considered as elements with unique rock material properties and connected to surrounding matrix elements. Using FRACMESH, individual fractures may have uniform or random aperture distributions to consider heterogeneity. Fracture element volumes and interfacial areas are calculated from fracture geometry within individual elements. By using FRACMESH and TOUGH2, fractures with various inclinations and orientations, and fracture-matrix interaction, can be incorporated. In this paper, results of flow and transport simulations in a fractured rock block utilizing FRACMESH are presented.
Date: April 9, 2003
Creator: Ito, Kazumasa & Yongkoo, Seol
Partner: UNT Libraries Government Documents Department

4. pi. physics with the plastic ball

Description: 4 ..pi.. data taken with the Plastic Ball show that cluster production in relativistic nuclear collisions depends on both the size of the participant volume and the finite size of the cluster. The measurement of the degree of thermalization and the search for collective flow will permit the study of the applicability of macroscopic concepts such as temperature and density.
Date: October 1, 1982
Creator: Gutbrod, H.H.; Loehner, H.; Poskanzer, A.M.; Renner, T.; Riedesel, H.; Ritter, H.G. et al.
Partner: UNT Libraries Government Documents Department

25 years of technical advances in RFQ accelerators

Description: The radio frequency quadrupole (RFQ) accelerator began as 'The ion linear accelerator with space-uniform strong focusing' conceived by I. M. Kapchinskii and V. A. Teplyakove. In 1979, R. H. Stokes, K. R. Crandall, J. E. Stovall and D. A. Swenson gave this concept the name RFQ. And by 1983, at least 15 laboratories throughout the world were working on various FWQ designs. In the early years, there were many types of geometry considered for the RFQ, but only a few types have survived. The two cavity geometries now used in almost all RFQs are the 4-vane and 4-rod structures. The 4-vane structure is the most popular because its operating frequency range (80 to -500 MHz) is suitable for light ions. Heavy ions require low frequencies (below 200 MHz). Because the 4-rod structure has smaller transverse dimensions than a 4-vane RFQ at the same frequency, the 4-rod RFQ is often preferred for these applications. This paper will describe how the RFQ accelerates and focuses the beam. The paper also discusses some of the important technical advances in designing and building RFQs.
Date: January 1, 2002
Creator: Young, L. M. (Lloyd M.)
Partner: UNT Libraries Government Documents Department

805 MHz and 201 MHz RF cavity development for MUCOOL

Description: A muon cooling channel calls for very high acceleratinggradient RF structures to restore the energy lost by muons in theabsorbers. The RF structures have to be operated in a strong magneticfield and thus the use of superconducting RF cavities is excluded. Toachieve a high shunt impedance while maintaining a large enough apertureto accommodate a large transverse emittance muon beam, the cavity designadopted is a pillbox-like geometry with thin Be foils to terminate theelectromagnetic field at the cavity iris. The possibility of using gridsof thin-walled metallic tubes for the termination is also being explored.Many of the RF-related issues for muon cooling channels are being studiedboth theoretically and experimentally using an 805 MHz cavity that has apillbox-like geometry with thin Be windows to terminate the cavityaperture. The design and performance of this cavity are reported here.High-power RF tests of the 805 MHz cavity are in progress at Lab G inFermilab. The cavity has exceeded its design gradient of 30 MV/m,reaching 34 MV/m without external magnetic field. No surface damage wasobserved at this gradient. The cavity is currently under conditioning atLab G with an external magnetic field of 2.5 T. We also present here a201 MHz cavity design for muoncooling channels. The proposed cavitydesign is also suitable for use in a proof-of-principle Muon IonizationCooling Experiment (MICE).
Date: October 10, 2002
Creator: DLi@lbl.gov
Partner: UNT Libraries Government Documents Department

1991 annual report to the National Science Foundation

Description: The Geometry Center research program has a number of different aspects, most of which involve longer term commitments, such as, development of research software, teams of individuals visually exploring mathematical structures and sponsoring of workshops. The Center is built on the research programs of its faculty. These programs have flourished and interacted under the Center umbrella. There are many interconnections and commonalities between the fields represented. Here, a summary of the research work of each of the faculty members. Some of the research topics are geometric calculus of variations, group theory, geometric algorithms, and computer graphics.
Date: December 1, 1991
Partner: UNT Libraries Government Documents Department

1992 annual report to the National Science Foundation

Description: The Geometry Center research program has a number of different aspects. This report documents the work of the past year. The activities described here are organized under intertwined areas: manifold geometry and associated group theory; optimal geometries; dynamical systems; and computational geometry and computer graphics.
Date: December 31, 1992
Partner: UNT Libraries Government Documents Department

2D accelerator design for SITEX negative ion source

Description: Solving the Poisson-Vlasov equations where the magnetic field, B, is assumed constant, we optimize the optical system of a SITEX negative ion source in infinite slot geometry. Algorithms designed to solve the above equations were modified to include the curved emitter boundary data appropriate to a negative ion source. Other configurations relevant to negative ion sources are examined.
Date: January 1, 1983
Creator: Whealton, J.H.; Raridon, R.J.; McGaffey, R.W.; McCollough, D.H.; Stirling, W.L. & Dagenhart, W.K.
Partner: UNT Libraries Government Documents Department

3D CFD Model of a Multi-Cell High Temperature Electrolysis Stack

Description: A three-dimensional computational fluid dynamics (CFD) electrochemical model has been created to model high-temperature electrolysis stack performance and steam electrolysis in the Idaho National Laboratory Integrated Lab Scale (ILS) experiment. The model is made of 60 planar cells stacked on top of each other operated as Solid Oxide Electrolysis Cells (SOEC). Details of the model geometry are specific to a stack that was fabricated by Ceramatec, Inc1. and tested at the Idaho National Laboratory. Inlet and outlet plenum flow and distribution are considered. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT2. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC userdefined subroutine was modified for this work to allow for operation in the SOEC mode. Model results provide detailed profiles of temperature, Nernst potential, operating potential, activation overpotential, anode-side gas composition, cathode-side gas composition, current density and hydrogen production over a range of stack operating conditions. Variations in flow distribution, and species concentration are discussed. End effects of flow and per-cell voltage are also considered.
Date: November 1, 2007
Creator: Hawkes, G. L.; O'Brien, J. E. & Stoots, C. M.
Partner: UNT Libraries Government Documents Department

3D Magnetotelluic characterization of the Coso GeothermalField

Description: Electrical resistivity may contribute to progress inunderstanding geothermal systems by imaging the geometry, bounds andcontrolling structures in existing production, and thereby perhapssuggesting new areas for field expansion. To these ends, a dense grid ofmagnetotelluric (MT) stations plus a single line of contiguous bipolearray profiling has been acquired over the east flank of the Cosogeothermal system. Acquiring good quality MT data in producing geothermalsystems is a challenge due to production related electromagnetic (EM)noise and, in the case of Coso, due to proximity of a regional DCintertie power transmission line. To achieve good results, a remotereference completely outside the influence of the dominant source of EMnoise must be established. Experimental results so far indicate thatemplacing a reference site in Amargosa Valley, NV, 65 miles from the DCintertie, isstill insufficient for noise cancellation much of the time.Even though the DC line EM fields are planar at this distance, theyremain coherent with the nonplanar fields in the Coso area hence remotereferencing produces incorrect responses. We have successfully unwrappedand applied MT times series from the permanent observatory at Parkfield,CA, and these appear adequate to suppress the interference of thecultural EM noise. The efficacy of this observatory is confirmed bycomparison to stations taken using an ultra-distant reference site eastof Socorro, NM. Operation of the latter reference was successful by usingfast ftp internet communication between Coso Junction and the New MexicoInstitute of Mining and Technology, using the University of Utah site asintermediary, and allowed referencing within a few hours of datadownloading at Coso. A grid of 102 MT stations was acquired over the Cosogeothermal area in 2003 and an additional 23 stations were acquired toaugment coverage in the southern flank of the first survey area in 2005.These data have been inverted to a fully three-dimensional conductivitymodel. Initial analysis of the Coso MT data was carried out using ...
Date: April 23, 2007
Creator: Newman, Gregory A.; Hoversten, G. Michael; Wannamaker, Philip E. & Gasperikova, Erika
Partner: UNT Libraries Government Documents Department

3D Magnetotelluric characterization of the COSO GeothermalField

Description: Knowledge of the subsurface electrical resistivity/conductivity can contribute to a better understanding of complex hydrothermal systems, typified by Coso geothermal field, through mapping the geometry (bounds and controlling structures) over existing production. Three-dimensional magnetotelluric (MT) inversion is now an emerging technology for characterizing the resistivity structures of complex geothermal systems. The method appears to hold great promise, but histories exploiting truly 3D inversion that demonstrate the advantages that can be gained by acquiring and analyzing MT data in three dimensions are still few in number. This project will address said issue, by applying 3D MT forward modeling and inversion to a MT data set acquired over the Coso geothermal field. The goal of the project is to provide the capability to image large geothermal reservoirs in a single self-consistent model. Initial analysis of the Coso MT data has been carried out using 2D MT imaging technology to construct an initial 3D resistivity model from a series of 2D resistivity images obtained using the inline electric field measurements (Zxy impedance elements) along different measurement transects. This model will be subsequently refined through a 3D inversion process. The initial 3D resistivity model clearly shows the controlling geological structures possibly influencing well production at Coso. The field data however, also show clear three dimensionality below 1 Hz, demonstrating the limitations of 2D resistivity imaging. The 3D MT predicted data arising from this starting model show good correspondence in dominant components of the impedance tensor (Zxy and Zyx) above 1Hz. Below 1 Hz there is significant differences between the field data and the 2D model data.
Date: January 1, 2005
Creator: Newman, Gregory A.; Hoversten, Michael; Gasperikova, Erika & Wannamaker, Philip E.
Partner: UNT Libraries Government Documents Department

3D visualization for the MARS14 Code

Description: A new three-dimensional visualization engine has been developed for the MARS14 code system. It is based on the OPENINVENTOR graphics library and integrated with the MARS built-in two-dimensional Graphical-User Interface, MARS-GUI-SLICE. The integrated package allows thorough checking of complex geometry systems and their fragments, materials, magnetic fields, particle tracks along with a visualization of calculated 2-D histograms. The algorithms and their optimization are described for two geometry classes along with examples in accelerator and detector applications.
Date: January 23, 2003
Creator: Rzepecki, Jaroslaw P.; Kostin, Mikhail A. & Mokhov, Nikolai V.
Partner: UNT Libraries Government Documents Department

Ablation Front Rayleigh-Taylor Growth Experiments in Spherically Convergent Geometry

Description: Experiments were performed on the Nova laser, using indirectly driven capsules mounted in cylindrical gold hohlraums, to measure the Rayleigh-Taylor growth at the ablation front by time-resolved radiography. Modulations were preformed on the surface of Ge-doped plastic capsules. With initial modulations of 4 {micro}m, growth factors of about 6 in optical depth were seen, in agreement with simulations using the radiation hydrocode FCI2. With initial modulations of 1 {micro}m, growth factors of about 100-150 in optical depth were seen. The Rayleigh-Taylor (RT) instability at the ablation front in an inertial confinement fusion capsule has been the subject of considerable investigation. Much of this research has been concentrated on planar experiments, in which RT growth is inferred from radiography. The evolution is somewhat different in a converging geometry; the spatial wavelength decreases (affecting the onset of nonlinear saturation), and the shell thickens and compresses rather than decompressing as in a planar geometry. In a cylindrically convergent geometry, the latter effect is proportional to the radius, while in spherically convergent geometry, the latter effect is proportional to the radius squared. Experiments were performed on the Nova and Omega lasers in cylindrical geometry (using both direct and indirect drive) and have been performed in spherical geometry using direct drive.
Date: November 3, 1999
Creator: Glendinning, S.G.; Cherfils, C.; Colvin, J.; Divol, L.; Galmiche, D.; Haan, S. et al.
Partner: UNT Libraries Government Documents Department

Accelerating Battery Design Using Computer-Aided Engineering Tools: Preprint

Description: Computer-aided engineering (CAE) is a proven pathway, especially in the automotive industry, to improve performance by resolving the relevant physics in complex systems, shortening the product development design cycle, thus reducing cost, and providing an efficient way to evaluate parameters for robust designs. Academic models include the relevant physics details, but neglect engineering complexities. Industry models include the relevant macroscopic geometry and system conditions, but simplify the fundamental physics too much. Most of the CAE battery tools for in-house use are custom model codes and require expert users. There is a need to make these battery modeling and design tools more accessible to end users such as battery developers, pack integrators, and vehicle makers. Developing integrated and physics-based CAE battery tools can reduce the design, build, test, break, re-design, re-build, and re-test cycle and help lower costs. NREL has been involved in developing various models to predict the thermal and electrochemical performance of large-format cells and has used in commercial three-dimensional finite-element analysis and computational fluid dynamics to study battery pack thermal issues. These NREL cell and pack design tools can be integrated to help support the automotive industry and to accelerate battery design.
Date: January 1, 2011
Creator: Pesaran, A.; Heon, G. H. & Smith, K.
Partner: UNT Libraries Government Documents Department

Accelerating Design of Batteries Using Computer-Aided Engineering Tools (Presentation)

Description: Computer-aided engineering (CAE) is a proven pathway, especially in the automotive industry, to improve performance by resolving the relevant physics in complex systems, shortening the product development design cycle, thus reducing cost, and providing an efficient way to evaluate parameters for robust designs. Academic models include the relevant physics details, but neglect engineering complexities. Industry models include the relevant macroscopic geometry and system conditions, but simplify the fundamental physics too much. Most of the CAE battery tools for in-house use are custom model codes and require expert users. There is a need to make these battery modeling and design tools more accessible to end users such as battery developers, pack integrators, and vehicle makers. Developing integrated and physics-based CAE battery tools can reduce the design, build, test, break, re-design, re-build, and re-test cycle and help lower costs. NREL has been involved in developing various models to predict the thermal and electrochemical performance of large-format cells and has used in commercial three-dimensional finite-element analysis and computational fluid dynamics to study battery pack thermal issues. These NREL cell and pack design tools can be integrated to help support the automotive industry and to accelerate battery design.
Date: November 1, 2010
Creator: Pesaran, A.; Kim, G. H. & Smith, K.
Partner: UNT Libraries Government Documents Department

Accurate monotonicity-preserving cubic interpolation

Description: A simple and effective algorithm to construct a monotonicity-preserving cubic Hermite interpolant for data with rapid variations is presented. Constraining the derivatives of the interpolant according to geometric considerations makes the interpolant consistent with local monotonicity properties of the data. Numerical examples are given that compare the quality and accuracy of the proposed interpolation method with other standard interpolants.
Date: February 1, 1982
Creator: Hyman, J. M.
Partner: UNT Libraries Government Documents Department

Acquisition of building geometry in the simulation of energy performance

Description: Building geometry is essential to any simulation of building performance. This paper examines the importing of building geometry into simulation of energy performance from the users' point of view. It lists performance requirements for graphic user interfaces that input building geometry, and discusses the basic options in moving from two- to three-dimensional definition of geometry and the ways to import that geometry into energy simulation. The obvious answer lies in software interoperability. With the BLIS group of interoperable software one can interactively import building geometry from CAD into EnergyPlus and dramatically reduce the effort otherwise needed for manual input.The resulting savings may greatly increase the value obtained from simulation, the number of projects in which energy performance simulation is used, and expedite decision making in the design process.
Date: June 28, 2001
Creator: Bazjanac, Vladimir
Partner: UNT Libraries Government Documents Department