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in subjects: "Flow Models"

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Pressure losses in fracture-dominated reservoirs: the wellbore constriction effect

Improved energy production from many types of energy reservoirs such as hot dry rock geothermal as well as hydraulically fractured oil, gas, and other geothermal reservoirs requires a better understanding of the fluid mechanics in the vicinity of the fracture-wellbore intersection. Typically, the aperture (smallest dimension) of a hydraulic fracture is only of the order of 1 mm (0.04 in.) so that reasonable energy production rates from geothermal systems require fairly large flow velocities wit… more

Date: January 1, 1980

Creator: Murphy, H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Evaluation of proposed designs for streamflow monitoring structures at waste disposal sites

Design of small surface water monitoring stations associated with waste sites requires an approach that balances several problems. The monitoring site must have a capacity for a wide range of flows, allow accurate measurements over the full performance range, minimize effects from accumulation of contaminated sediments, and minimize costs of construction and operation. Selecting a station design that takes these factors into consideration can be done systematically through use of formal decisio… more

Date: January 1, 1991

Creator: Clapp, R. B.; Borders, D. M.; Tardiff, M. F. & Huff, D. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ocean thermal difference power plant turbine design

No Description Available.

Date: November 1, 1973

Creator: Ambs, L. L. & Marshall, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Coordinate system control: adaptive meshes

The discussion of the formulation and properties of the adaptive mesh algorithm is as complete as space permits. As should be clear from the discussion, adaptive gridding is most useful for singular perturbation problems where localized regions with large gradients develop spontaneously. Often, choosing the correct weight function is not trivial, and, sometimes, it is appropriate to cause the mesh to respond to structure in several dependent variables simultaneously.

Date: January 1, 1982

Creator: Brackbill, J.U.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A Theoretical Study of the Transient Operation and Stability of Two-Phase Natural Circulation Loops

Mathematical models of the time-dependent behavior of two-phase natural- circulation loops were used to predict the operation and to explain the unusual instability sometimes observed. The initial results obtained for a loop similar to the Univ. of Minnesota loop were used to formulate a more complex and accurate model, and the predicted transient behavior was in close agreement with the experimental results from the Minnesota loop. For a 300psia, high-pressure loop, unstable oscillatory behavi… more

Date: June 1, 1961

Creator: Garlid, K.; Amundson, N. R. & Isbin, H. S.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Identification of fluid-flow paths in the Cerro Prieto geothermal field

A hydrogeologic model of the Cerro Prieto geothermal field has been developed based on geophysical and lithologic well logs, downhole temperature, and well completion data from about 90 deep wells. The hot brines seem to originate in the eastern part of the field, flowing in a westward direction and rising through gaps in the shaly layers which otherwise act as partial caprocks to the geothermal resource.

Date: May 1, 1982

Creator: Halfman, S. E.; Lippmann, M. J.; Zelwer, R. & Howard, J. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A survey of air flow models for multizone structures

Air flow models are used to simulate the rates of incoming and outgoing air flows for a building with known leakage under given weather and shielding conditions. Additional information about the flow paths and air-mass flows inside the building can only by using multizone air flow models. In order to obtain more information on multizone air flow models, a literature review was performed in 1984. A second literature review and a questionnaire survey performed in 1989, revealed the existence of 5… more

Date: March 1, 1991

Creator: Feustel, H.E. & Dieris, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Critical flow: General theory and spurious solutions

It is hardly necessary to emphasize the importance that an accurate prediction of the parameters of critical flow plays in a number of industries, notably in nuclear reactor safety calculations and in metering. In spite of its importance, the literature of the subject still contains erroneous statements. Many of them result from an unjustified belief in the generality of certain conclusions drawn in the elementary study of one-dimensional isentropic flow of a perfect gas with constant specific … more

Date: May 1, 1991

Creator: Kestin, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

TOPAZ - the transient one-dimensional pipe flow analyzer: code validation and sample problems

TOPAZ is a ''user friendly'' computer code for modeling the one-dimensional-transient physics of multi-species gas transfer in arbitrary arrangements of pipes, valves, vessels, and flow branches. This document presents a series of sample problems designed to aid potential users in creating TOPAZ input files. To the extent possible, sample problems were selected for which analytical solutions currently exist. TOPAZ comparisons with such solutions are intended to provide a measure of code validat… more

Date: October 1, 1985

Creator: Winters, W.S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Analysis of the mist lift process for mist flow open-cycle OTEC

Preliminary results are presented of a numerical analysis to study the open-cycle mist flow process for ocean thermal energy conversion (OTEC). Emphasis in the analysis is on the mass transfer and fluid mechanics of the steady-state mist flow. The analysis is based on two one-dimensional models of the mist lift process: a single-group model describes a mist composed of a single size of drops and a multigroup model considers a spectrum of drop sizes. The single-group model predicts that the lift… more

Date: June 1, 1980

Creator: Davenport, R. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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ICRF (Ion Cyclotron Range of Frequencies) edge modeling studies

Theoretical models have been developed, and are currently being refined, to explain the edge plasma-antenna interaction that occurs during ICRF heating. The periodic structure of a Faraday shielded antenna is found to result in strong ponderomotive force in the vicinity of the antenna. A fluid model, which incorporates the ponderomotive force, shows an increase in transport to the Faraday shield. A kinetic model shows that the strong antenna near fields act to increase the energy of deuterons w… more

Date: January 1, 1989

Creator: Lehrman, I.S. (Grumman Aerospace Corp., Princeton, NJ (USA). Corporate Research Center) & Colestock, P.L. (Princeton Univ., NJ (USA). Plasma Physics Lab.)

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A subregion block iteration to 3-D finite element modeling of subsurface flow

A subregion block iteration (SBI) technique has been developed in conjunction with finite element approximations of saturated-unsaturated flow equations. The proposed SBI technique is implemented in a three-dimensional finite element saturated-unsaturated flow model. The model is verified with a nonlinear diffusion equation having an analytical solution. It is then applied to a burial trench problem. It is not possible to solve this field problem using the direct elimination finite element meth… more

Date: January 1, 1988

Creator: Yeh, G.T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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PORMC: A model for Monte Carlo simulation of fluid flow, heat, and mass transport in variably saturated geologic media

This computer program was developed in support of environmental restoration activities being conducted at the Hanford Site to comply with the Resource Conservation and Recovery Act of 1976 and its 1984 amendum; the Comprehensive Environmental Response, Compensation, and Liability Act as amended in 1986; and the Hanford Federal Facility Agreement and Consent Order (Ecology et al. 1990). The results of analyses made using the computer program will be used in remedial investigations to study the p… more

Date: September 1, 1991

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Flow regimes

Internal boundaries in multiphase flow greatly complicate fluid-dynamic and heat-transfer descriptions. Different flow regimes or topological configurations can have radically dissimilar interfacial and wall mass, momentum, and energy exchanges. To model the flow dynamics properly requires estimates of these rates. In this paper the common flow regimes for gas-liquid systems are defined and the techniques used to estimate the extent of a particular regime are described. Also, the current comput… more

Date: January 1, 1982

Creator: Liles, D.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The renormalization group and lattice QCD

This report discusses the following topics: scaling of thermodynamic quantities and critical exponents; scaling relations; block spin idea of Kadanoff; exact RG solution of the 1-d Ising model; Wilson's formulation of the renormalization group; linearized transformation matrix and classification of exponents; derivation of exponents from the eigenvalues of {Tau}{sub {alpha}{beta}}; simple field theory: the gaussian model; linear renormalization group transformations; numerical methods: MCRG; bl… more

Date: January 1, 1989

Creator: Gupta, R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Installation restoration program: Hydrologic measurements with an estimated hydrologic budget for the Joliet Army Ammunition Plant, Joliet, Illinois. [Contains maps of monitoring well locations, topography and hydrologic basins]

Hydrologic data were gathered from the 36.8-mi{sup 2} Joliet Army Ammunition Plant (JAAP) located in Joliet, Illinois. Surface water levels were measured continuously, and groundwater levels were measured monthly. The resulting information was entered into a database that could be used as part of numerical flow model validation for the site. Deep sandstone aquifers supply much of the water in the JAAP region. These aquifers are successively overlain by confining shales and a dolomite aquifer of… more

Date: July 1, 1991

Creator: Diodato, D. M.; Cho, H. E. & Sundell, R. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Development and utilization of new diagnostics for dense-phase pneumatic transport

Dense-phase pneumatic transport is an attractive means of conveying solids. Unfortunately, because of the high solid concentrations, this transport method is a difficult regime in which to carry out detailed measurements. Hence most details of the flow are unknown. In this context, the main objective of this work is to develop probes for local measurements of solid velocity and holdup in dense gas-solid flows. Because we anticipate the recent theories of rapid granular flows will bring insight … more

Date: January 1, 1991

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development and evaluation of a meter for measuring return line fluid flow rates during drilling

The most costly problem routinely encountered in geothermal drilling is lost circulation, which occurs when drilling fluid is lost to the formation rather than circulating back to the surface. The successful and economical treatment of lost circulation requires the accurate measurement of drilling fluid flow rate both into and out of the well. This report documents the development of a meter for measuring drilling fluid outflow rates in the return line of a drilling rig. The meter employs a rol… more

Date: June 1, 1992

Creator: Loeppke, G. E.; Schafer, D. M.; Glowka, D. A.; Scott, D. D.; Wernig, M. D. & Wright, E. K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Detailed report on tested models companion report 2 to simulation of geothermal subsidence (LBL 10571)

An assessment was performed of existing mathematical models for subsidence simulation and prediction. Detailed analyses are presented of the theory, power, usability, and performance of the seven models used in conjunction with an ongoing research program aimed at improved understanding and control of ground movements caused by geothermal power production. The models used were: hand-calculation techniques; the nucleus-of-strain method; the one-dimensional Terzaghi consolidation method; the two-… more

Date: March 1, 1980

Creator: Miller, I.; Dershowitz, W.; Jones, K.; Myer, L.; Roman, K. & Schauer, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Conceptual model for regional radionuclide transport from a salt dome repository: a technical memorandum

Disposal of high-level radioactive wastes is a major environmental problem influencing further development of nuclear energy in this country. Salt domes in the Gulf Coast Basin are being investigated as repository sites. A major concern is geologic and hydrologic stability of candidate domes and potential transport of radionuclides by groundwater to the biosphere prior to their degradation to harmless levels of activity. This report conceptualizes a regional geohydrologic model for transport of… more

Date: May 30, 1980

Creator: Kier, R.S.; Showalter, P.A. & Dettinger, M.D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Characterization of Open-Cycle Coal-Fired MHD Generators. 16th Quarterly Technical Progress Report, December 16, 1980-March 31, 1981

The successful design of full-scale, open-cycle, coal-fired MHD generators for baseload electrical production requires a detailed understanding of the plasma chemical and plasma dynamic characteristics of anticipated combustor and channel fluids. Progress in efforts to model the efficiency of an open-cycle, coal-fired MHD channel based on the characterization of the channel flow as well as laboratory experiments to validate the modeling effort is reported. In addition, studies related to unders… more

Date: May 1, 1981

Creator: Wormhoudt, J.; Yousefian, V.; Weinberg, M.; Kolb, C.; Martinez-Sanchez, M.; Cheng, W. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Stability of flows in fluidized beds

In this paper we carry out a systematic linearized stability analysis of the state of uniform fluidization for a fluid infused with granular particles. We carry out an interesting optimization procedure which leads to bounds for certain parameters, within which the state of uniform fluidization is stable. We find that this stability depends critically on the structure of the pressure-like term. (VC)

Date: January 1, 1992

Creator: Rajagopal, C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Quench detection by fluid dynamic means in cable-in-conduit superconductors

The tight confinement of the helium in cable-in-conduit superconductors creates protection problems because of the substantial pressure rise that can occur during a quench. But the same pressure rise offers the useful possibility of a non-electrical means of detecting incipient quenches by monitoring the outflow from the various hydraulic paths of the magnet. If the method is to work, the signal must be large enough to be detected unambiguously at an early enough time, and the signal must not d… more

Date: June 1, 1987

Creator: Dresner, L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Behavior of temperature and concentration of shallow groundwater in the Raft River Geothermal Area

A moderate-temperature (140/sup 0/C) geothermal power plant demonstration, sponsored by the Department of Energy, is currently under development in South Central Idaho. Environmental concerns about the quality of the local shallow groundwater prompted a modeling study. Simulation results (1) suggest significant thermal and quality levels within the 30-year projected plant operation and (2) makes obvious the importance of understanding the interconnected hydraulic systems.

Date: May 1, 1980

Creator: Tang, D.H.; Goldman, D.; Martinez, J.A. & Lantz, R.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department