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A discontinuous Galerkin front tracking method for two-phase flows with surface tension

Description: A Discontinuous Galerkin method for solving hyperbolic systems of conservation laws involving interfaces is presented. The interfaces are represented by a collection of element boundaries and their position is updated using an arbitrary Lagrangian-Eulerian method. The motion of the interfaces and the numerical fluxes are obtained by solving a Riemann problem. As the interface is propagated, a simple and effective remeshing technique based on distance functions regenerates the grid to preserve i… more
Date: December 28, 2008
Creator: Nguyen, V. T.; Peraire, J.; Cheong, K. B. & Persson, P. O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A capillary valve for microfluidic systems.

Description: Microfluidic systems are becoming increasingly complicated as the number of applications grows. The use of microfluidic systems for chemical and biological agent detection, for example, requires that a given sample be subjected to many process steps, which requires microvalves to control the position and transport of the sample. Each microfluidic application has its own specific valve requirements and this has precipitated the wide variety of valve designs reported in the literature. Each of th… more
Date: October 1, 2004
Creator: Cummings, Eric B.; Kanouff, Michael P. & Rush, Brian M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Capillary-Pumped Passive Reactor Concept for Space Nuclear Power

Description: To develop the passively-cooled space reactor concept using the capillary-induced lithium flow, since molten lithium possesses a very favorable surface tension characteristic. In space where the gravitational field is minimal, the gravity-assisted natural convection cooling is not effective nor an option for reactor heat removal, the capillary induced cooling becomes an attractive means of providing reactor cooling.
Date: May 30, 2008
Creator: Lin, Dr. Thomas F.; Hughes, Dr. Thomas G. & Miller, Christopher G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fabrication and Characterization of Suspended Carbon Nanotube Devices in Liquid

Description: Suspended carbon nanotube devices are a promising platform for future bio-electronic applications. Suspended carbon nanotube transistors have been previously fabricated in air; however all previous attempts to bring them into liquid failed. We analyze forces acting on the suspended nanotube devices during immersion into liquids and during device operation and show that surface tension forces acting on the suspended nanotubes during transfer into the liquid phase are responsible for the nanotube… more
Date: October 30, 2006
Creator: Artyukhin, A.; Stadermann, M.; Stroeve, P.; Bakajin, O. & Noy, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Wet-Etch Figuring: Optical Surfacing by Controlled Application of Etchant Solution Using the marangoni Effect

Description: Wet-etch figuring (WEF), a computer-controlled method for generating arbitrarily shaped optical surfaces using wet chemical etching, has been developed. This method uses applicator geometry and surface tension gradients (the Marangoni Effect) to define and confine the footprint of a wetted etchant zone on the surface. Capillary forces attach the flowing etchant solution to the underside of the optic being figured. No mechanical or thermal stresses or residues are applied to the optic by this pr… more
Date: May 17, 2001
Creator: Rushford, M. C.; Britten, J. A.; Hoaglan, C. R.; Thomas, I. M.; Summers, L. J. & Dixit, S. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Seismic Absorption and Modulus Measurements in Porous Rocks in Lab and Field: Physical, Chemical, and Biological Effects of Fluids (Detecting a Biosurfactant Additive in a Field Irrigation Experiment)

Description: We have been exploring a new technology that is based on using low-frequency seismic attenuation data to monitor changes in fluid saturation conditions in two-fluid phase porous materials. The seismic attenuation mechanism is related to the loss of energy due to the hysteresis of resistance to meniscus movement (changes in surface tension, wettability) when a pore containing two fluids is stressed at very low frequencies (< 10 Hz). This technology has potential applications to monitoring cha… more
Date: May 1, 2006
Creator: Spetzler, Hartmut
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Foam Transport in Porous Media - A Review

Description: Amendment solutions with or without surfactants have been used to remove contaminants from soil. However, it has drawbacks such that the amendment solution often mobilizes the plume, and its movement is controlled by gravity and preferential flow paths. Foam is an emulsion-like, two-phase system in which gas cells are dispersed in a liquid and separated by thin liquid films called lamellae. Potential advantages of using foams in sub-surface remediation include providing better control on the vo… more
Date: November 11, 2009
Creator: Zhang, Z. F.; Freedman, Vicky L. & Zhong, Lirong
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mineral-Surfactant Interactions for Minimum Reagents Precipitation and Adsorption for Improved Oil Recovery

Description: Chemical EOR can be an effective method for increasing oil recovery and reducing the amount of produced water; however, reservoir fluids are chemically complex and may react adversely to the polymers and surfactants injected into the reservoir. While a major goal is to alter rock wettability and interfacial tension between oil and water, rock-fluid and fluid-fluid interactions must be understood and controlled to minimize reagent loss, maximize recovery and mitigate costly failures. The overall… more
Date: September 20, 2008
Creator: Somasundaran, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical and Microbial Characterization of North Slope Viscous Oils to Assess Viscosity Reduction and Enhanced Recovery

Description: A large proportion of Alaska North Slope (ANS) oil exists in the form of viscous deposits, which cannot be produced entirely using conventional methods. Microbially enhanced oil recovery (MEOR) is a promising approach for improving oil recovery for viscous deposits. MEOR can be achieved using either ex situ approaches such as flooding with microbial biosurfactants or injection of exogenous surfactant-producing microbes into the reservoir, or by in situ approaches such as biostimulation of indig… more
Date: December 31, 2008
Creator: Patil, Shirish; Dandekar, Abhijit & Leigh, Mary Beth
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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First principles study of the aggregation of oligo and polythiophene cations in solution

Description: The stacking of positively charged (or doped) terthiophene oligomers and quaterthiophene polymers in solution is investigated applying a recently developed unified electrostatic and cavitation model for first-principles calculations in a continuum solvent. The thermodynamic and structural patterns of the dimerization are explored in different solvents, and the distinctive roles of polarity and surface tension are characterized and analyzed. Interestingly, we discover a saturation in the stabili… more
Date: November 14, 2005
Creator: Scherlis, D A; Fattebert, J & Marzari, N
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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INEEL Biotechnology for Oilfield Application--Microbial Enhanced Oil Recovery FY-03 Report

Description: The Idaho National Engineering and Environmental Laboratory (INEEL) Biotechnology for Oilfield Operations program supports development, engineering, and application of biotechnology for exploration and production. This continuing INEEL program also supports mitigation of detrimental field conditions. The program is consistent with the United States Department of Energy mission to ¡§promote activities and policies through its oil technology and natural gas supply programs to enhance the efficien… more
Date: November 1, 2003
Creator: Bala, G. A.; Bruhn, D. F.; Fox, S. L.; Noah, K. S.; Schaller, K. D.; Robertson, E. P. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nanostructured surfaces for microfluidics and sensing applications.

Description: The present work demonstrates the use of light to move liquids on a photoresponsive monolayer, providing a new method for delivering analyses in lab-on-chip environments for microfluidic systems. The light-driven motion of liquids was achieved on photoresponsive azobenzene modified surfaces. The surface energy components of azobenzene modified surfaces were calculated by Van Oss theory. The motion of the liquid was achieved by generation of a surface tension gradient by isomerization of azobenz… more
Date: January 1, 2007
Creator: Picraux, Samuel Thomas (Arizona State University); Piech, Marcin (United Technologies Corp.); Schneider, John F.; Vail, Sean (Arizona State University); Hayes, Mark A. (Arizona State University); Garcia, Anthony A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Multiphase Flow in Complex Fracture Apertures under a Wide Range of Flow Conditions

Description: A better understanding of multiphase flow through fractures requires knowledge of the detailed physics of interfacial flows at the microscopic pore scale. The objective of our project was to develop tools for the simulation of such phenomena. Complementary work was performed by a group led by Dr.~Paul Meakin of the Idaho National Engineering and Environmental Laboratory. Our focus was on the lattice-Boltzmann (LB) method. In particular, we studied both the statics and dynamics of contact lines … more
Date: December 12, 2006
Creator: Rothman, Daniel H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wetting and free surface flow modeling for potting and encapsulation.

Description: As part of an effort to reduce costs and improve quality control in encapsulation and potting processes the Technology Initiative Project ''Defect Free Manufacturing and Assembly'' has completed a computational modeling study of flows representative of those seen in these processes. Flow solutions are obtained using a coupled, finite-element-based, numerical method based on the GOMA/ARIA suite of Sandia flow solvers. The evolution of the free surface is solved with an advanced level set algorit… more
Date: June 1, 2007
Creator: Brooks, Carlton, F.; Brooks, Michael J.; Graham, Alan Lyman; Noble, David Frederick; Notz, Patrick K.; Hopkins, Matthew Morgan et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Understanding metal vaporizaiton from laser welding.

Description: The production of metal vapor as a consequence of high intensity laser irradiation is a serious concern in laser welding. Despite the widespread use of lasers in manufacturing, little fundamental understanding of laser/material interaction in the weld pool exists. Laser welding experiments on 304 stainless steel have been completed which have advanced our fundamental understanding of the magnitude and the parameter dependence of metal vaporization in laser spot welding. Calculations using a thr… more
Date: September 1, 2003
Creator: DebRoy, Tarasankar (The Pennsylvania State University, University Park, PA); Fuerschbach, Phillip William; He, Xiuli (The Pennsylvania State University, University Park, PA) & Norris, Jerome T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effects of Microbial and Phosphate Amendments on the Bioavailability of Lead (Pb) in Shooting Range Soil

Description: Heavy metals including lead (Pb) are released continually into the environment as a result of industrial, recreational, and military activities. Lead ranked number two on the CERCLA Priority List of Hazardous Substances and was identified as a major hazardous chemical found on 47% of USEPA's National Priorities List sites (Hettiarachchi and Pierzynski 2004). In-situ remediation of lead (Pb) contaminated soils may be accomplished by changing the soil chemistry and structure with the application … more
Date: June 16, 2005
Creator: Brigmon, Robin; Wilson, Christina; Knox, Anna; Seaman, John & Smith, Garriet
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Aluminum Leaching of ''Archived'' Sludge from Tanks 8F, 11H, and 12H

Description: Aluminum can promote formation or dissolution of networks in hydroxide solid solutions. When present in large amounts it will act as a network former increasing both the viscosity and the surface tension of melts. This translates into poor free flow properties that affect pour rate of glass production in the Defense Waste Processing Facility (DWPF). To mitigate this situation, DWPF operations limit the amount of aluminum contained in sludge. This study investigated the leaching of aluminum comp… more
Date: March 12, 2004
Creator: Fondeur, Fernando F.; Hobbs, D. T. & Fink, S. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High Resolution Prediction of Gas Injection Process Performance for Heterogeneous Reservoirs Quarterly Report

Description: This report outlines progress in the second quarter of the third year of the DOE project ''High Resolution Prediction of Gas Injection Process Performance for Heterogeneous Reservoirs''. This report presents results of an investigation of the effects of variation in interfacial tension (IFT) on three-phase relative permeability. We report experimental results that demonstrate the effect of low IFT between two of three phases on the three-phase relative permeabilities. In order to create three-p… more
Date: March 31, 2003
Creator: Franklin M. Orr, Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rapid Migration of Radionuclides Leaked from High-Level Waste Tanks: A Study of Salinity Gradients, Wetted Path Geometry, and Water Vapor Transport

Description: This study combines laboratory, field, and numerical experiments with the following objectives: to investigate the effect of elevated surface tension, density, and viscosity of highly saline fluids on soil water-retention properties, wetting front instability, the formation and persistence of fingers, and contaminant mobility to investigate the conditions under which osmotically driven vapor flux is operative and quantify its impact on plume transport to develop and incorporate a theory describ… more
Date: June 1, 2000
Creator: Ward, Anderson L.; Gee, Glendon; Selker, John & Tyler, Scott
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of Microorganisms with Improved Transport and Biosurfactant Activity for Enhanced Oil Recovery: Final Report

Description: The project had three objectives: (1) to develop microbial strains with improved biosurfactant properties that use cost-effective nutrients, (2) to obtain biosurfactant strains with improved transport properties through sandstones, and (3) to determine the empirical relationship between surfactant concentration and interfacial tension and whether in situ reactions kinetics and biosurfactant concentration meets appropriate engineering design criteria. Here, we show that a lipopeptide biosurfacta… more
Date: August 15, 2005
Creator: McInerney, M. J.; Duncan, K. E.; Youssef, N.; Fincher, T.; Maudgalya, S. K.; Folmsbee, M. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Prevention of Porosity Formation and Other Effects of Gaseous Elements in Iron Castings

Description: Iron foundries have observed porosity primarily as interdendritic porosity in large freezing range alloys such as Ni-Hard I and hypoeutectic high Cr alloys or pinholes and fissure defects in gray and ductile irons. For most iron foundries, porosity problems occur sporadically, but even occasional outbreaks can be costly since even a very small amount of porosity can significantly reduce the mechanical properties of the castings. As a result when porosity is detected, the castings are scrapped a… more
Date: April 1, 2005
Creator: Center, Albany Research
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of Dewatering Aids for Minerals and Coal Fines

Description: MCT has developed a suite of novel dewatering chemicals (or aids) that are designed to cause a decrease in the capillary pressures of the water trapped in a filter cake by (1) decreasing the surface tension of water, (2) increasing the contact angles of the particles to be dewatered, and (3) causing the particles to coagulate, all at the same time. The decrease in capillary pressure in turn causes an increase in the rate filtration, an increase in throughput, and a decrease in pressure drop req… more
Date: July 1, 2004
Creator: Yoon, Roe-Hoam; Asmatulu, Ramazan; Yildirim, Ismail; Jansen, William; Zhang, Jinmig; Atkinson, Brad et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flow of two-dimensional liquid metal jet in a strong magnetic field.

Description: Steady, two-dimensional flow of a liquid metal jet pouring vertically down from a nozzle in the presence of crossed magnetic and electric fields has been investigated. The magnetic field is supposed to have a single component transverse to the flow. An asymptotic, high Hartmann number model has been used to study a combined effect of surface tension, nonuniform magnetic field, gravity and inertia. Relations have been obtained for a jet issuing from a duct, pouring into a draining duct, pouring … more
Date: November 4, 2002
Creator: Reed, C. B. & Molokov, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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