Modeling of geothermal reservoirs: Fundamental processes, computer simulation, and field applications (open access)

Modeling of geothermal reservoirs: Fundamental processes, computer simulation, and field applications

This article attempts to critically evaluate the present state of the art of geothermal reservoir simulation. Methodological aspects of geothermal reservoir modeling are briefly reviewed, with special emphasis on flow in fractured media. Then we examine applications of numerical simulation to studies of reservoir dynamics, well test design and analysis, and modeling of specific fields. Tangible impacts of reservoir simulation technology on geothermal energy development are pointed out. We conclude with considerations on possible future developments in the mathematical modeling of geothermal fields. 45 refs., 4 figs., 2 tabs.
Date: September 1, 1988
Creator: Pruess, K.
Object Type: Article
System: The UNT Digital Library
Models for aqueous electrolyte mixtures for systems extending from dilute range to the fused salt: Evaluation of parameters to high temperatures and pressures (open access)

Models for aqueous electrolyte mixtures for systems extending from dilute range to the fused salt: Evaluation of parameters to high temperatures and pressures

Models based on general equations for the excess Gibbs energy of the aqueous fluid provide thermodynamically consistent structures for evaluating and predicting aqueous electrolyte properties. These equations yield other quantities upon appropriate differentiation, including osmotic and activity coefficients, excess enthalpies, heat capacities, and volumes. For this reason a wide array of experimental data are available from which model parameters and their temperature or pressure dependence can be evaluated. For systems of moderate concentration, the most commonly used model at present is the ion-interaction approach and coworkers. For more concentrated solutions, including those extending to the fused salt, an alternate model based on a Margules-expansion and commonly used for nonelectrolytes was proposed. We discuss these two models and give examples of parameter evaluations for some geologically relevant systems to high temperatures and pressures; also we show applications of the models to calculations of solubility equilibria.
Date: September 1, 1988
Creator: Pabalan, R.T. & Pitzer, K.S.
Object Type: Article
System: The UNT Digital Library
Molecular thermodynamics of polymer melts at interfaces (open access)

Molecular thermodynamics of polymer melts at interfaces

A lattice model is developed for the prediction of structure and thermodynamic properties at free polymer melt surfaces and polymer melt/solid interfaces. Density variations in the interfacial region are taken into account by introducing voids in the lattice, in the spirit of the equation of state theory of Sanchez and Lacombe. Intramolecular energy (chain stiffness) effects are explicitly incorporated. The model is derived through a rigorous statistical mechanical and thermodynamic analysis, which is based on the concept of availability. Two cases are considered: ''full equilibrium,'' whereby the interfacial polymer is taken as free to exchange heat, work and mass with a bulk polymer phase at given temperature and pressure; and ''restricted equilibrium,'' whereby a thin polymer film is allowed to equilibrate locally in response to ambient temperature and pressure, but in which chains do not necessarily have the same chemical potential as in the unconstrained bulk. Techniques are developed for calculating surface tension, adhesion tension, density profiles, chain shape, bond orientation, as well as the distribution of segments of various orders in the interfacial region. 28 refs., 6 figs.
Date: September 1, 1988
Creator: Theodorou, D.N.
Object Type: Report
System: The UNT Digital Library
Multiaxial graphite test specimen (open access)

Multiaxial graphite test specimen

A multiaxial test program is to be conducted by Oak Ridge National Laboratory (ORNL) on the core component graphite. The objectives of the tests are to obtain failure data under uniaxial and biaxial states of stress in order to construct a failure surface in a two-dimensional stress space. These data will be used in verifying the accuracy of the maximum stress failure theory being proposed for use in designing the core graphite components. Tubular specimens are proposed to be used and are either loaded axially and/or subjected to internal pressure. This report includes a study on three specimen configurations. The conclusions of that study indicate that an elliptical transition geometry procedures the smallest discontinuity effects. Several loading combustions were studied using the elliptical transition specimen. The primary purpose is to establish the location of the highest stress state and its relation to the gage section for all of the loading conditions. The tension/internal pres sure loading condition (1:1) indicated that the high stress area is just outside the gage section but still should be acceptable. 5 refs., 18 figs.
Date: September 1, 1988
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Multiple Dissociation of /sup 16/O, /sup 14/N, and /sup 12/C at 32. 5 MeV/Nucleon (open access)

Multiple Dissociation of /sup 16/O, /sup 14/N, and /sup 12/C at 32. 5 MeV/Nucleon

An array of 34 fast/slow plastic scintillators has been used to identify fragments from the breakup of /sup 16/O, /sup 14/N, and /sup 12/C projectiles at 32.5 MeV/nucleon, scattered by a Au target. The dissociation of /sup 16/O into as many as five charged particles has been observed. The yields of the different channels correlate approximately with the threshold energy for separation of the projectile into the observed fragments. The excitation spectrum of the primary projectile fragment was deduced from the measured positions and kinetic energies of the individual fragments. These spectra show that, although most of the decomposition proceeds through excitation energies within /approximately/20 MeV of the lower particle-decay thresholds, excitation energies extending up to /approximately/80 MeV can be produced in the primary stage of the reaction. This represents a significant acquisition of energy by the projectile. Calculations of the yields based on a sequence of binary decays have been presented. Reactions in which one or two units of charge are acquired by the projectile were also observed. 25 refs., 10 figs.
Date: September 1, 1988
Creator: Stokstad, R. G.; Chan, Y. D.; Dacal, A.; DiGregorio, D. E.; Harmon, B. A.; Knop, R. et al.
Object Type: Article
System: The UNT Digital Library
New approaches to linear and nonlinear programming (open access)

New approaches to linear and nonlinear programming

This report describes technical progress during the past twelve months on DOE Contract DE-FG-87ER25030 and requests support for the third year. The project involves study of the theoretical properties and computational performance of techniques that solve linear and nonlinear programs by means of nonlinear transformations. The group at the Systems Optimization Laboratory (SOL) were the first to recognize the connection between Karmarkar's projective method and the logarithmic barrier method. It is now generally recognized that essentially all interior-point methods for linear programming inspired by Karmarkar's method are closely related to application of Newton's method to a sequence of barrier functions. Each barrier function is defined from the objective function and a barrier term that is infinite along the boundary of the feasible region. As the weight on the barrier term is reduced to zero, the solution of the subproblem becomes closer to the solution of the original problem.
Date: September 1, 1988
Creator: Murray, W. & Saunders, M.A.
Object Type: Report
System: The UNT Digital Library
New approaches to linear and nonlinear programming. Progress report, January 1, 1988--December 31, 1988 (open access)

New approaches to linear and nonlinear programming. Progress report, January 1, 1988--December 31, 1988

This report describes technical progress during the past twelve months on DOE Contract DE-FG-87ER25030 and requests support for the third year. The project involves study of the theoretical properties and computational performance of techniques that solve linear and nonlinear programs by means of nonlinear transformations. The group at the Systems Optimization Laboratory (SOL) were the first to recognize the connection between Karmarkar`s projective method and the logarithmic barrier method. It is now generally recognized that essentially all interior-point methods for linear programming inspired by Karmarkar`s method are closely related to application of Newton`s method to a sequence of barrier functions. Each barrier function is defined from the objective function and a barrier term that is infinite along the boundary of the feasible region. As the weight on the barrier term is reduced to zero, the solution of the subproblem becomes closer to the solution of the original problem.
Date: September 1, 1988
Creator: Murray, W. & Saunders, M. A.
Object Type: Report
System: The UNT Digital Library
New topological invariants for non-abelian antisymmetric tensor fields from extended BRS algebra (open access)

New topological invariants for non-abelian antisymmetric tensor fields from extended BRS algebra

Extended non-linear BRS and Gauge transformations containing Lie algebra cocycles, and acting on non-abelian antisymmetric tensor fields are constructed in the context of free differential algebras. New topological invariants are given in this framework. 6 refs.
Date: September 1, 1988
Creator: Boukraa, S.; Maillet, J.M. & Nijhoff, F.
Object Type: Article
System: The UNT Digital Library
A new version of a free electron laser Two-Beam Accelerator (open access)

A new version of a free electron laser Two-Beam Accelerator

A new version of a Two-Beam Accelerator is proposed in which in each period of the drive structure a very small input microwave signal is amplified to a large power level and then completely removed and transferred to the accelerating structure. In this manner a number of difficulties with the original version are eliminated or greatly relieved; namely, rf phase and amplitude sensitivity, growth of sidebands, and rf manipulation (removal of the microwaves from the drive structure, and transmission of microwave power through the accelerating cavities). 11 refs., 6 figs., 2 tabs.
Date: September 1, 1988
Creator: Sessler, A. M.; Sternbach, E. & Wurtele, J. S.
Object Type: Article
System: The UNT Digital Library
Nonlinear gyrokinetic Maxwell-Vlasov equations using magnetic coordinates (open access)

Nonlinear gyrokinetic Maxwell-Vlasov equations using magnetic coordinates

A gyrokinetic formalism using magnetic coordinates is used to derive self-consistent, nonlinear Maxwell-Vlasov equations that are suitable for particle simulation studies of finite-..beta.. tokamak microturbulence and its associated anomalous transport. The use of magnetic coordinates is an important feature of this work as it introduces the toroidal geometry naturally into our gyrokinetic formalism. The gyrokinetic formalism itself is based on the use of the Action-variational Lie perturbation method of Cary and Littlejohn, and preserves the Hamiltonian structure of the original Maxwell-Vlasov system. Previous nonlinear gyrokinetic sets of equations suitable for particle simulation analysis have considered either electrostatic and shear-Alfven perturbations in slab geometry, or electrostatic perturbations in toroidal geometry. In this present work, fully electromagnetic perturbations in toroidal geometry are considered. 26 refs.
Date: September 1, 1988
Creator: Brizard, A.
Object Type: Report
System: The UNT Digital Library
Novel concept development of an internal recirculation catalyst for mild gasification (open access)

Novel concept development of an internal recirculation catalyst for mild gasification

The objective of this program is to provide an overall evaluation of a novel process concept for mild gasification by completing work in three major tasks: (1) Laboratory-Scale Experiments, (2) Bench-Scale Tests, and (3) Proof-of-Concept Tests and Evaluation (optional). During this quarter, experimental work involving zinc chloride as a potential recirculating catalyst for coal, initiated in the previous quarter, was continued. The design of an all-quartz laboratory-scale isothermal free-fall reactor was completed, and construction was begun. One free-fall experiment was performed in an existing stainless-steel free-fall reactor with methanol-treated Illinois No. 6 high-volatile bituminous coal. 1 ref., 2 figs., 2 tabs.
Date: September 1, 1988
Creator: Knight, R. A. & Babu, S. P.
Object Type: Report
System: The UNT Digital Library
Novel concept development of an internal recirculation catalyst for mild gasification. Progress report, March 1, 1988--May 31, 1988 (open access)

Novel concept development of an internal recirculation catalyst for mild gasification. Progress report, March 1, 1988--May 31, 1988

The objective of this program is to provide an overall evaluation of a novel process concept for mild gasification by completing work in three major tasks: (1) Laboratory-Scale Experiments, (2) Bench-Scale Tests, and (3) Proof-of-Concept Tests and Evaluation (optional). During this quarter, experimental work involving zinc chloride as a potential recirculating catalyst for coal, initiated in the previous quarter, was continued. The design of an all-quartz laboratory-scale isothermal free-fall reactor was completed, and construction was begun. One free-fall experiment was performed in an existing stainless-steel free-fall reactor with methanol-treated Illinois No. 6 high-volatile bituminous coal. 1 ref., 2 figs., 2 tabs.
Date: September 1, 1988
Creator: Knight, R. A. & Babu, S. P.
Object Type: Report
System: The UNT Digital Library
Nuclear effects in J//psi/ and lepton-pair production (open access)

Nuclear effects in J//psi/ and lepton-pair production

High-energy processes in nuclear media provide important tests of quantum chromodynamics, since in principle one can use the nuclear environment to perturb and study the mechanisms involved in confinement and hadronization. In this talk several examples of nuclear effects in QCD will be discussed that affect the propagation and hadronization of quarks and gluons in nuclear matter. The issues include: possible signatures for quark-gluon plasma formation in heavy ion collisions, particularly J//psi/ production; hadronization due to jet coalescence; the limits of validity of QCD factorization formulae due to initial- and final-state interactions; formation zone physics; shadowing of the quark and gluon structure functions of nuclei; and color transparency in hard quasielastic reactions inside of nuclei. 29 refs., 4 figs.
Date: September 1, 1988
Creator: Brodsky, Stanley J.
Object Type: Article
System: The UNT Digital Library
Nuclear facility decommissioning and site remedial actions: A selected bibliography, volume 9 (open access)

Nuclear facility decommissioning and site remedial actions: A selected bibliography, volume 9

The 604 abstracted references on nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the ninth in a series of reports prepared annually for the US Department of Energy's Remedial Action Programs. Foreign and domestic literature of all types--technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions--has been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy's remedial action programs. Major sections are (1) Surplus Facilities Management Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Program, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Uranium Mill Tailings Management, (7) Technical Measurements Center, and (8) General Remedial Action Program Studies. Subsections for sections 1, 2, 5, and 6 include: Design, Planning, and Regulations; Environmental Studies and Site Surveys; Health, Safety, and Biomedical Studies; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication description. Indexes are provided for author, corporate affiliation, …
Date: September 1, 1988
Creator: Owen, P. T.; Knox, N. P.; Michelson, D. C. & Turmer, G. S.
Object Type: Report
System: The UNT Digital Library
Nuclear fission and transuranium elements: Fifty years ago (open access)

Nuclear fission and transuranium elements: Fifty years ago

This paper reviews some historical aspects of the knowledge and discovery of transuranium elements. This fission of plutonium is discussed also. 12 refs., 6 figs.
Date: September 1, 1988
Creator: Seaborg, G. T.
Object Type: Article
System: The UNT Digital Library
Nuclear Science Division annual report, October 1, 1986--September 30, 1987 (open access)

Nuclear Science Division annual report, October 1, 1986--September 30, 1987

This report summarizes the activities of the Nuclear Science Division during the period October 1, 1986 to September 30, 1987. A highlight of the experimental program during this time was the completion of the first round of heavy-ion running at CERN with ultrarelativistic oxygen and sulfur beams. Very rapid progress is being made in the analysis of these important experiments and preliminary results are presented in this report. During this period, the Bevalac also continued to produce significant new physics results, while demand for beam time remained high. An important new community of users has arrived on the scene, eager to exploit the unique low-energy heavy-beam capabilities of the Bevalac. Another major highlight of the program has been the performance of the Dilepton Spectrometer which has entered into production running. Dileptons have been observed in the p + Be and Ca + Ca reactions at several bombarding energies. New data on pion production with heavy beams measured in the streamer chamber to shed light on the question of nuclear compressibility, while posing some new questions concerning the role of Coulomb forces on the observed pion spectra. In another quite different area, the pioneering research with radioactive beams is continuing and …
Date: September 1, 1988
Creator: Mahoney, J. (ed.)
Object Type: Report
System: The UNT Digital Library
Nuclear waste treatment program: Annual report for FY 1987 (open access)

Nuclear waste treatment program: Annual report for FY 1987

Two of the US Department of Energy's (DOE) nuclear waste management-related goals are to ensure that waste management is not an obstacle to the further development of light-water reactors and the closure of the nuclear fuel cycle and to fulfill its institutional responsibility for providing safe storage and disposal of existing and future nuclear wastes. As part of its approach to achieving these goals, the Office of Remedial Action and Waste Technology of DOE established what is now called the Nuclear Waste Treatment Program (NWTP) at the Pacific Northwest Laboratory during the second half of FY 1982. To support DOE's attainment of its goals, the NWTP is to provide technology necessary for the design and operation of nuclear waste treatment facilities by commercial enterprises as part of a licensed waste management system and problem-specific treatment approaches, waste form and treatment process adaptations, equipment designs, and trouble-shooting assistance, as required to treat existing wastes. This annual report describes progress during FY 1987 towards meeting these two objectives. 24 refs., 59 figs., 24 tabs.
Date: September 1, 1988
Creator: Brouns, R. A. & Powell, J. A. (comps.)
Object Type: Report
System: The UNT Digital Library
Observed asymptotic properties of low-degree solar gravity-mode eigenfrequencies (open access)

Observed asymptotic properties of low-degree solar gravity-mode eigenfrequencies

The asymptotic properties of the low-degree solar gravity modes classified by Hill and Gu are studied in the framework of first- and second-order asymptotic theory predictions. The results of this analysis demonstrate the necessity of retaining the second-order term in asymptotic theory to describe the eigenfrequency spectrum. In this theory, there are two first-order parameters, T/sub 0/ and delta, and two second-order parameters, V/sub 1/ and V/sub 2/. Values of the parameters obtained in this analysis are: T/sub 0/ = 36.31 +- 0.12 min, delta = /minus/0.43 +- 0.13, V/sub 1/ = 0.35, and V/sub 2/ = 4.76. There remain differences of approx.0.3 ..mu..Hz between the asymptotic theory eigenfrequencies and observed eigenfrequencies which are quasi-periodic functions of the radial order n for a given value of the degree /ell/. 26 refs., 1 fig., 1 tab.
Date: September 1988
Creator: Gu, Ye-ming; Hill, Henry A. & Rosenwald, Ross D.
Object Type: Article
System: The UNT Digital Library
On the algebraic structure of integrable systems in multidimensions (open access)

On the algebraic structure of integrable systems in multidimensions

The d-simplex equations are multidimensional generalizations of the Yang-Baxter (triangle) equations. We discuss the algebraic structure of the hierarchy of the d-simplex equations and their relevance to the notion of quantum and classical integrability. A multidimensional generalization of the notion of lax pair is given. 7 refs.
Date: September 1, 1988
Creator: Maillet, J.M. & Nijhoff, F.
Object Type: Article
System: The UNT Digital Library
Optimized conical shaped charge design using the SCAP (Shaped Charge Analysis Program) code (open access)

Optimized conical shaped charge design using the SCAP (Shaped Charge Analysis Program) code

The Shaped Charge Analysis Program (SCAP) is used to analytically model and optimize the design of Conical Shaped Charges (CSC). A variety of existing CSCs are initially modeled with the SCAP code and the predicted jet tip velocities, jet penetrations, and optimum standoffs are compared to previously published experimental results. The CSCs vary in size from 0.69 inch (1.75 cm) to 9.125 inch (23.18 cm) conical liner inside diameter. Two liner materials (copper and steel) and several explosives (Octol, Comp B, PBX-9501) are included in the CSCs modeled. The target material was mild steel. A parametric study was conducted using the SCAP code to obtain the optimum design for a 3.86 inch (9.8 cm) CSC. The variables optimized in this study included the CSC apex angle, conical liner thickness, explosive height, optimum standoff, tamper/confinement thickness, and explosive width. The non-dimensionalized jet penetration to diameter ratio versus the above parameters are graphically presented. 12 refs., 10 figs., 7 tabs.
Date: September 1, 1988
Creator: Vigil, M.G.
Object Type: Report
System: The UNT Digital Library
The organization and operation of the Savannah River Plant`s groundwater monitoring program. Revision 3 (open access)

The organization and operation of the Savannah River Plant`s groundwater monitoring program. Revision 3

The Savannah River Plant (SRP) is operated by Du Pont for the Department of Energy. The plant has been operating since 1952 and is one of the largest industrial facilities in the nation. Its function is to produce nuclear materials for the national defense. This paper describes the organization and operation of the Groundwater Monitoring Program (GMP) at the SRP. Groundwater has been actively monitored for radiological parameters at the SRP since the commencement of site operations in the 1950s. More recently, monitoring expanded to include chemical parameters and numerous additional facilities. The GMP is a large monitoring program. Over 700 wells monitor more than 70 facilities which are spread over 300 square miles. The program includes both Du Pont personnel and contractors and is responsible for all phases of groundwater monitoring: the installation (or abandonment) of monitoring wells, the determination of water quality (sample collection, analysis, data review, etc.), and the generation of reports.
Date: September 1988
Creator: Olson, C. M. & Heffner, J. D.
Object Type: Report
System: The UNT Digital Library
The Pacific Northwest residential consumer: Perceptions and preferences of home heating fuels, major appliances, and appliance fuels (open access)

The Pacific Northwest residential consumer: Perceptions and preferences of home heating fuels, major appliances, and appliance fuels

In 1983 the Bonneville Power Administration contracted with the Pacific Northwest Laboratory (PNL) to conduct an analysis of the marketing environment for Bonneville's conservation activities. Since this baseline residential study, PNL has conducted two follow up market research projects: Phase 2 in 1985, and Phase 3, in 1988. In this report the respondents' perceptions, preferences, and fuel switching possibilities of fuels for home heating and major appliances are examined. To aid in effective target marketing, the report identifies market segments according to consumers' demographics, life-cycle, attitudes, and opinions.
Date: September 1, 1988
Creator: Harkreader, S. A. & Hattrup, M. P.
Object Type: Report
System: The UNT Digital Library
Partitioning of hydrogen in the vanadium-lithium-hydrogen system at elevated temperatures (open access)

Partitioning of hydrogen in the vanadium-lithium-hydrogen system at elevated temperatures

Equilibrium concentrations of hydrogen in vanadium-base alloys exposed to flowing lithium at temperatures from 350 to 550/degree/C in a forced-circulation loop were measured by residual gas analysis and the vacuum fusion method. Residual gas analysis and removal of material from the surface allowed a determination of the spatial hydrogen distribution in the alloys. These experimental results were compared with calculated thermodynamic distribution coefficients for hydrogen in the vanadium/lithium system. Small amounts of other solutes in the molten lithium and in the alloys affected the solubility, diffusivity, and resultant distribution of hydrogen. Thermodynamic calculations demonstrated the importance of major alloying elements to the partitioning of hydrogen. 12 refs., 5 figs., 2 tabs.
Date: September 1, 1988
Creator: Hull, A. B.; Chopra, O. K.; Loomis, B. A. & Smith, D. L.
Object Type: Article
System: The UNT Digital Library
PEGASYS: A proposed internal target-spectrometer facility for the PEP storage ring (open access)

PEGASYS: A proposed internal target-spectrometer facility for the PEP storage ring

A proposal for an internal gas-jet target and forward spectrometer for the PEP storage ring is described. The beam structure, allowable luminosity (L=10/sup 33/ cm/sup /minus/2/s/sup /minus/1/ for H/sub 2/, D/sub 2/ decreasing as Z/sup /minus/1.75/ for nuclear targets) and energy (E/sub e/less than or equal to 15 GeV) make the ring ideal for multiparticle coincidence studies in the scaling regime, and where perturbative QCD may be an apt description of some exclusive and semi-inclusive reactions. 17 refs., 5 figs.
Date: September 1, 1988
Creator: Van Bibber, K.
Object Type: Article
System: The UNT Digital Library