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Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Horizontal Window Frames with Internal Cavities

Description: This paper assesses the accuracy of the simplified frame cavity conduction/convection and radiation models presented in ISO 15099 and used in software for rating and labeling window products. Temperatures and U-factors for typical horizontal window frames with internal cavities are compared; results from Computational Fluid Dynamics (CFD) simulations with detailed radiation modeling are used as a reference. Four different frames were studied. Two were made of polyvinyl chloride (PVC) and two of… more
Date: December 1, 2008
Creator: Gustavsen, Arlid; Kohler, Christian; Dalehaug, Arvid & Arasteh, Dariush
Partner: UNT Libraries Government Documents Department
open access

Development of Next Generation Multiphase Pipe Flow Prediction Tools

Description: The developments of fields in deep waters (5000 ft and more) is a common occurrence. It is inevitable that production systems will operate under multiphase flow conditions (simultaneous flow of gas-oil-and water possibly along with sand, hydrates, and waxes). Multiphase flow prediction tools are essential for every phase of the hydrocarbon recovery from design to operation. The recovery from deep-waters poses special challenges and requires accurate multiphase flow predictive tools for several … more
Date: August 31, 2008
Creator: Flow, Tulsa Fluid
Partner: UNT Libraries Government Documents Department
open access

Characterization of EGS Fracture Network Lifecycles

Description: Geothermal energy is relatively clean, and is an important non-hydrocarbon source of energy. It can potentially reduce our dependence on fossil fuels and contribute to reduction in carbon emissions. High-temperature geothermal areas can be used for electricity generation if they contain permeable reservoirs of hot water or steam that can be extracted. The biggest challenge to achieving the full potential of the nation’s resources of this kind is maintaining and creating the fracture networks re… more
Date: March 31, 2008
Creator: Foulger, Gillian R.
Partner: UNT Libraries Government Documents Department
open access

Grand Research Questions in the Solid-Earth Sciences Final Scientific/Technical Report

Description: Over the past three decades, Earth scientists have made great strides in understanding our planet’s workings and history. Yet this progress has served principally to lay bare more fundamental questions about the Earth. Expanding knowledge is generating new questions, while innovative technologies and new partnerships with other sciences provide new paths toward answers. A National Academies committee was established to frame some of the great intellectual challenges inherent in the study of the… more
Date: December 3, 2008
Creator: Linn, Anne M.
Partner: UNT Libraries Government Documents Department
open access

Ion Exclusion by Sub 2-nm Carbon Nanotube Pores

Description: Carbon nanotubes offer an outstanding platform for studying molecular transport at nanoscale, and have become promising materials for nanofluidics and membrane technology due to their unique combination of physical, chemical, mechanical, and electronic properties. In particular, both simulations and experiments have proved that fluid flow through carbon nanotubes of nanometer size diameter is exceptionally fast compared to what continuum hydrodynamic theories would predict when applied on this … more
Date: April 9, 2008
Creator: Fornasiero, F; Park, H G; Holt, J K; Stadermann, M; Grigoropoulos, C P; Noy, A et al.
Partner: UNT Libraries Government Documents Department
open access

Poroelastic modeling of fracture-seismic wave interaction

Description: Rock containing a compliant, fluid-filled fracture can be viewed as one case of heterogeneous poroelastic media. When this fracture is subjected to seismic waves, a strong contrast in the elastic stiffness between the fracture itself and the background can result in enhanced grain-scale local fluid flow. Because this flow--relaxing the pressure building up within the fracture--can increase the dynamic compliance of the fracture and change energy dissipation (attenuation), the scattering of seis… more
Date: August 15, 2008
Creator: Nakagawa, Seiji
Partner: UNT Libraries Government Documents Department
open access

Attenuated Vector Tomography -- An Approach to Image Flow Vector Fields with Doppler Ultrasonic Imaging

Description: The measurement of flow obtained using continuous wave Doppler ultrasound is formulated as a directional projection of a flow vector field. When a continuous ultrasound wave bounces against a flowing particle, a signal is backscattered. This signal obtains a Doppler frequency shift proportional to the speed of the particle along the ultrasound beam. This occurs for each particle along the beam, giving rise to a Doppler velocity spectrum. The first moment of the spectrum provides the directional… more
Date: May 15, 2008
Creator: Huang, Qiu; Peng, Qiyu; Huang, Bin; Cheryauka, Arvi & Gullberg, Grant T.
Partner: UNT Libraries Government Documents Department
open access

Development of a Numerical Simulator for Analyzing the Geomechanical Performance of Hydrate-Bearing Sediments

Description: In this paper, we describe the development and application of a numerical simulator that analyzes the geomechanical performance of hydrate-bearing sediments, which may become an important future energy supply. The simulator is developed by coupling a robust numerical simulator of coupled fluid flow, hydrate thermodynamics, and phase behavior in geologic media (TOUGH+HYDRATE) with an established geomechanical code (FLAC3D). We demonstrate the current simulator capabilities and applicability for … more
Date: June 1, 2008
Creator: Rutqvist, Jonny; Rutqvist, J. & Moridis, G.J.
Partner: UNT Libraries Government Documents Department
open access

Investigation of the Richtmyer-Meshkov instability

Description: The present program is centered on the experimental study of shock-induced interfacial fluid instabilities. Both 2-D (near-sinusoids) and 3-D (spheres) initial conditions are studied in a large, vertical square shock tube facility. The evolution of the interface shape, its distortion, the modal growth rates and the mixing of the fluids at the interface are all objectives of the investigation. In parallel to the experiments, calculations are performed using the Raptor code, on platforms made ava… more
Date: December 22, 2008
Creator: Bonazza, Riccardo; Anderson, Mark & Oakley, Jason
Partner: UNT Libraries Government Documents Department
open access

Physical Model Development and Benchmarking for MHD Flows in Blanket Design

Description: An advanced simulation environment to model incompressible MHD flows relevant to blanket conditions in fusion reactors has been developed at HyPerComp in research collaboration with TEXCEL. The goals of this phase-II project are two-fold: The first is the incorporation of crucial physical phenomena such as induced magnetic field modeling, and extending the capabilities beyond fluid flow prediction to model heat transfer with natural convection and mass transfer including tritium transport and p… more
Date: June 5, 2008
Creator: Munipalli, Ramakanth; P.-Y.Huang; C.Chandler; C.Rowell; M.-J.Ni; N.Morley et al.
Partner: UNT Libraries Government Documents Department
open access

Slow Waves in Fractures Filled with Viscous Fluid

Description: Stoneley guided waves in a fluid-filled fracture generally have larger amplitudes than other waves, and therefore, their properties need to be incorporated in more realistic models. In this study, a fracture is modeled as an infinite layer of viscous fluid bounded by two elastic half-spaces with identical parameters. For small fracture thickness, I obtain a simple dispersion equation for wave-propagation velocity. This velocity is much smaller than the velocity of a fluid wave in a Biot-type so… more
Date: January 8, 2008
Creator: Korneev, Valeri
Partner: UNT Libraries Government Documents Department
open access

Dissipative Particle Dynamics and Other Particle Methods for Multiphase Fluid Flow in Fractured and Porous Media

Description: Particle methods are much less computationally efficient than grid based numerical solution of the Navier Stokes equation, and they have been used much less extensively, particularly for engineering applications. However, they have important advantages for some applications. These advantages include rigorous mast conservation, momentum conservation and isotropy. In addition, there is no need for explicit interface tracking/capturing. Code development effort is relatively low, and it is relative… more
Date: June 1, 2008
Creator: Meakin, Paul & Xu, Zhijie
Partner: UNT Libraries Government Documents Department
open access

Enhanced Geothermal Systems Research and Development: Models of Subsurface Chemical Processes Affecting Fluid Flow

Description: Successful exploitation of the vast amount of heat stored beneath the earth’s surface in hydrothermal and fluid-limited, low permeability geothermal resources would greatly expand the Nation’s domestic energy inventory and thereby promote a more secure energy supply, a stronger economy and a cleaner environment. However, a major factor limiting the expanded development of current hydrothermal resources as well as the production of enhanced geothermal systems (EGS) is insufficient knowledge abou… more
Date: May 29, 2008
Creator: Moller, Nancy & H., Weare J.
Partner: UNT Libraries Government Documents Department
open access

Recovery Discontinuous Galerkin Jacobian-Free Newton-Krylov Method for All-Speed Flows

Description: A novel numerical algorithm (rDG-JFNK) for all-speed fluid flows with heat conduction and viscosity is introduced. The rDG-JFNK combines the Discontinuous Galerkin spatial discretization with the implicit Runge-Kutta time integration under the Jacobian-free Newton-Krylov framework. We solve fully-compressible Navier-Stokes equations without operator-splitting of hyperbolic, diffusion and reaction terms, which enables fully-coupled high-order temporal discretization. The stability constraint is … more
Date: July 1, 2008
Creator: Park, HyeongKae; Nourgaliev, Robert; Mousseau, Vincent & Knoll, Dana
Partner: UNT Libraries Government Documents Department
open access

Reservoir permeability from seismic attribute analysis

Description: In case of porous fluid-saturated medium the Biot's poroelasticity theory predicts a movement of the pore fluid relative to the skeleton on seismic wave propagation through the medium. This phenomenon opens an opportunity for investigation of the flow properties of the hydrocarbon-saturated reservoirs. It is well known that relative fluid movement becomes negligible at seismic frequencies if porous material is homogeneous and well cemented. In this case the theory predicts an underestimated sei… more
Date: February 15, 2008
Creator: Silin, Dmitriy; Goloshubin, G.; Silin, D.; Vingalov, V.; Takkand, G. & Latfullin, M.
Partner: UNT Libraries Government Documents Department
open access

Numerical Prediction of the Performance of Integrated Planar Solid-Oxide Fuel Cells, with Comparisons of Results from Several Codes

Description: A numerical study of the thermal and electrochemical performance of a single-tube Integrated Planar Solid Oxide Fuel Cell (IP-SOFC) has been performed. Results obtained from two finite-volume computational fluid dynamics (CFD) codes FLUENT and SOHAB and from a two-dimensional inhouse developed finite-volume GENOA model are presented and compared. Each tool uses physical and geometric models of differing complexity and comparisons are made to assess their relative merits. Several single-tube sim… more
Date: June 1, 2008
Creator: Hawkes, G. L.; O'Brien, J. E.; Haberman, B. A.; Marquis, A. J.; Baca, C. M.; Tripepi, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Thermal-chemical-mechanical feedback during fluid-rock interactions: Implications for chemical transport and scales of equilibria in the crust

Description: Our research evaluates the hypothesis that feedback amongst thermal-chemical-mechanical processes operative in fluid-rock systems alters the fluid flow dynamics of the system which, in turn, affects chemical transport and temporal and spatial scales of equilibria, thus impacting the resultant mineral textural development of rocks. Our methods include computational experimentation and detailed analyses of fluid-infiltrated rocks from well-characterized terranes. This work focuses on metamorphic … more
Date: August 13, 2008
Creator: Dutrow, Barbara
Partner: UNT Libraries Government Documents Department
open access

Discrete Fracture Network Models for Risk Assessment of Carbon Sequestration in Coal

Description: A software package called DFNModeler has been developed to assess the potential risks associated with carbon sequestration in coal. Natural fractures provide the principal conduits for fluid flow in coal-bearing strata, and these fractures present the most tangible risks for the leakage of injected carbon dioxide. The objectives of this study were to develop discrete fracture network (DFN) modeling tools for risk assessment and to use these tools to assess risks in the Black Warrior Basin of Al… more
Date: July 1, 2008
Creator: Pashin, Jack; Jin, Guohai; Zheng, Chunmiao; Chen, Song & McIntyre, Marcella
Partner: UNT Libraries Government Documents Department
open access

TOUGHREACT User's Guide: A Simulation Program for Non-isothermal Multiphase Reactive Geochemical Transport in Variably Saturated Geologic Media, V1.2.1

Description: Coupled modeling of subsurface multiphase fluid and heat flow, solute transport, and chemical reactions can be applied to many geologic systems and environmental problems, including geothermal systems, diagenetic and weathering processes, subsurface waste disposal, acid mine drainage remediation, contaminant transport, and groundwater quality. TOUGHREACT has been developed as a comprehensive non-isothermal multi-component reactive fluid flow and geochemical transport simulator to investigate th… more
Date: September 29, 2008
Creator: Xu, Tianfu; Sonnenthal, Eric; Spycher, Nicolas & Pruess, Karsten
Partner: UNT Libraries Government Documents Department
open access

Two-phase viscoelastic jetting

Description: A coupled finite difference algorithm on rectangular grids is developed for viscoelastic ink ejection simulations. The ink is modeled by the Oldroyd-B viscoelastic fluid model. The coupled algorithm seamlessly incorporates several things: (1) a coupled level set-projection method for incompressible immiscible two-phase fluid flows; (2) a higher-order Godunov type algorithm for the convection terms in the momentum and level set equations; (3) a simple first-order upwind algorithm for the convect… more
Date: December 10, 2008
Creator: Yu, J.-D.; Sakai, S. & Sethian, J. A.
Partner: UNT Libraries Government Documents Department
open access

Final Report: "Large-Eddy Simulation of Anisotropic MHD Turbulence"

Description: To acquire better understanding of turbulence in flows of liquid metals and other electrically conducting fluids in the presence of steady magnetic fields and to develop an accurate and physically adequate LES (large-eddy simulation) model for such flows. The scientific objectives formulated in the project proposal have been fully completed. Several new directions were initiated and advanced in the course of work. Particular achievements include a detailed study of transformation of turbulence … more
Date: June 23, 2008
Creator: Zikanov, Oleg
Partner: UNT Libraries Government Documents Department
open access

A comparative simulation study of coupled THM processes and their effect on fractured rock permeability around nuclear waste repositories

Description: This paper presents an international, multiple-code, simulation study of coupled thermal, hydrological, and mechanical (THM) processes and their effect on permeability and fluid flow in fractured rock around heated underground nuclear waste emplacement drifts. Simulations were conducted considering two types of repository settings: (a) open emplacement drifts in relatively shallow unsaturated volcanic rock, and (b) backfilled emplacement drifts in deeper saturated crystalline rock. The results … more
Date: October 23, 2008
Creator: Rutqvist, Jonny; Barr, Deborah; Birkholzer, Jens T.; Fujisaki, Kiyoshi; Kolditz, Olf; Liu, Quan-Shen et al.
Partner: UNT Libraries Government Documents Department
open access

Geomechanical Performance of Hydrate-Bearing Sediment in Offshore Environments

Description: The objective of this multi-year, multi-institutional research project was to develop the knowledge base and quantitative predictive capability for the description of geomechanical performance of hydrate-bearing sediments (hereafter referred to as HBS) in oceanic environments. The focus was on the determination of the envelope of hydrate stability under conditions typical of those related to the construction and operation of offshore platforms. We have developed a robust numerical simulator of … more
Date: March 31, 2008
Creator: Holditch, Stephen; Patzek, Tad; Rutqvist, Jonny; Moridis, George & Plumb, Richard
Partner: UNT Libraries Government Documents Department
open access

A method for the three-dimensional simulation of superfluid helium

Description: Transport phenomena in superfluid helium can be described using the two-fluid Landau-Khalatnikov model and the Gorter-Mellink mutual friction. Here we discuss a mathematical formulation of the two-fluid model that uses macroscopic conservation balances of mass, momentum and energy of each species, and assumes local thermodynamic equilibrium. A particularity of this model is that it describes the state of He II as well as that of each of the two-fluid components in terms of pressure p and temper… more
Date: January 1, 2008
Creator: Bottura, L.; /CERN; Darve, C.; U., /Fermilab /Northwestern; Patankar, N.A.; U., /Northwestern et al.
Partner: UNT Libraries Government Documents Department
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