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TOUGH Short Course for Scientists and Engineers

Description: The TOUGH family of codes is a suite of computer programs for the simulation of multiphase fluid and heat flows in porous and fractured media with applications to geothermal reservoir engineering, nuclear waste disposal in geologic formations, geologic carbon sequestration, gas hydrate research, vadose zone hydrology, environmental remediation, oil and gas reservoir engineering, and other mass transport and energy transfer problems in complex geologic settings. TOUGH has been developed in the E… more
Date: August 1, 2006
Creator: Kowalsky, Michael B. & Finsterle, Stefan
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Application of Argonne's Glass Furnace Model to Longhor Glass Corporation Oxy-Fuel Furnace for the Production of Amber Glass.

Description: The objective of this project is to apply the Argonne National Laboratory's Glass Furnace Model (GFM) to the Longhorn oxy-fuel furnace to improve energy efficiency and to investigate the transport of gases released from the batch/melt into the exhaust. The model will make preliminary estimates of the local concentrations of water, carbon dioxide, elemental oxygen, and other subspecies in the entire combustion space as well as the concentration of these species in the furnace exhaust gas. This i… more
Date: September 6, 2006
Creator: Golchert, B.; Shell, J.; Jones, S.; Systems, Energy; Consulting, Shell Glass & Group, Anheuser-Busch Packaging
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: During this reporting period, further fundamental studies were conducted to understand the mechanism of the interactions between surfactants and minerals with the aim of minimizing chemical loss by adsorption. The effects of pH and mixing ratio on the chemical loss by adsorption were investigated. Some preliminary modeling work has been done towards the aim of developing a guide book to design optimal polymer/surfactant formula based on the understanding of adsorption and orientation of surfact… more
Date: April 30, 2006
Creator: Somasundaran, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preliminary Assessment of Potential Impacts to Dungeness Crabs from Disposal of Dredged Materials from the Columbia River

Description: Dredging of the Columbia River navigation channel has raised concerns about dredging-related impacts on Dungeness crabs (Cancer magister). The overall objectives of this effort are to synthesize what is known about disposal effects on Dungeness crabs (Phase 1) and to offer approaches to quantify the effects, including approaches to gain a population-level perspective on any effects found in subsequent studies (Phase 2). This report documents Phase 1, which included (1) development of a conceptu… more
Date: February 1, 2006
Creator: Pearson, Walter H.; Miller, Martin C.; Williams, Greg D.; Kohn, Nancy P. & Skalski, John R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

FIELD INVESTIGATIONS OF THE DRIFT SHADOW

Description: The ''Drift Shadow'' is defined as the relatively drier region that forms below subsurface cavities or drifts in unsaturated rock. Its existence has been predicted through analytical and numerical models of unsaturated flow. However, these theoretical predictions have not been demonstrated empirically to date. In this project they plan to test the drift shadow concept through field investigations and compare our observations to simulations. Based on modeling studies they have an identified suit… more
Date: January 15, 2006
Creator: G. W. Su, T. J. Kneafsey, T. A. Ghezzehei, B. D. Marshall, and P. J. Cook
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling the Cathodic Region in Crevice Corrosion Under a Thin Electrolyte Film Including Particulates

Description: Crevice corrosion may be limited by the capacity of the external cathodic region to support anodic dissolution currents within the crevice. The analysis here focuses on behavior of metal surfaces covered by a thin ({approx}microns) layer of the electrolyte film including particulates. The particulates can affect the cathode current capacity (I{sub total}) by increasing the solution resistance (''volume effect'') and by decreasing the electrode area (''surface effect''). In addition, there can b… more
Date: March 14, 2006
Creator: Agarwal, A. S.; Landau, U.; Shan, X. & Payer, J. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Challenges to Coupling Dynamic Geospatial Models

Description: Many applications of modeling spatial dynamic systems focus on a single system and a single process, ignoring the geographic and systemic context of the processes being modeled. A solution to this problem is the coupled modeling of spatial dynamic systems. Coupled modeling is challenging for both technical reasons, as well as conceptual reasons. This paper explores the benefits and challenges to coupling or linking spatial dynamic models, from loose coupling, where information transfer between … more
Date: June 23, 2006
Creator: Goldstein, N
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Accelerating DSMC data extraction.

Description: In many direct simulation Monte Carlo (DSMC) simulations, the majority of computation time is consumed after the flowfield reaches a steady state. This situation occurs when the desired output quantities are small compared to the background fluctuations. For example, gas flows in many microelectromechanical systems (MEMS) have mean speeds more than two orders of magnitude smaller than the thermal speeds of the molecules themselves. The current solution to this problem is to collect sufficient s… more
Date: October 1, 2006
Creator: Gallis, Michail A. & Piekos, Edward Stanley
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modal testing of the TX-100 wind turbine blade.

Description: This test report covers the SNL modal test results for two nominally identical TX-100 wind turbine blades. The TX-100 blade design is unique in that it features a passive braking, force-shedding mechanism where bending and torsion are coupled to produce desirable aerodynamic characteristics. A specific aim of this test is to characterize the coupling between bending and torsional dynamics. The results of the modal tests and the subsequent analysis characterize the natural frequencies, damping, … more
Date: May 1, 2006
Creator: Reese, Sarah; Griffith, Daniel Todd; Casias, Miguel; Simmermacher, Todd William & Smith, Gregory A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

An Exact Solution of Transport in Porous Media with Equilibrium and Kinetic Reactions

Description: This paper presents an analytical solution of reactive transport with equilibrium and kinetic reactions. A benchmark model of A {leftrightarrow} B {leftrightarrow} C {yields} chain reactions is developed for the purpose of verifying numerical computer codes and qualifying mathematical models. A reaction matrix is derived for both the equilibrium and first-order kinetic reactions and further decoupled as a diagonal matrix. Therefore, the partial differential equations (PDEs) coupled by the react… more
Date: April 12, 2006
Creator: Lu, X. & Sun, Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Reheating metastable O'Raifeartaigh models

Description: In theories with multiple vacua, reheating to a temperature greater than the height of a barrier can stimulate transitions from a desirable metastable vacuum to a lower energy state. We discuss the constraints this places on various theories and demonstrate that in a class of supersymmetric models this transition does not occur even for arbitrarily high reheating temperature.
Date: November 1, 2006
Creator: Fox, Patrick; Craig, Nathaniel J.; Fox, Patrick J. & Wacker, Jay G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Reheating Metastable O'Raifeartaigh Models

Description: In theories with multiple vacua, reheating to a temperature greater than the height of a barrier can stimulate transitions from a desirable metastable vacuum to a lower energy state. We discuss the constraints this places on various theories and demonstrate that in a class of supersymmetric models this transition does not occur even for arbitrarily high reheating temperature.
Date: December 5, 2006
Creator: Craig, Nathaniel J.; Fox, Patrick J. & Wacker, Jay G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Chemical Fate of Contaminants in the Environment: Chlorinated Hydrocarbons in the Groundwater

Description: Chlorinated hydrocarbons (CHCs) are the most common contaminant found at hazardous waste sites and are the most prevalent contaminants on U.S. Department of Energy (DOE) weapons production sites. Many of the CHCs are either known or suspected carcinogens and thus pose health risks to the public and/or site workers. Unlike simple hydrocarbons, CHCs are resistant to biodegradation, but can degrade by abiotic processes such as hydrolysis, nucleophilic substitution, and dehydrochlorination. Unfortu… more
Date: September 21, 2006
Creator: Truhlar, Donald G.; Cramer, Christopher; Gao, Jiali; Garrett, Bruce C.; Dupuis, Michel; Straatsma, TP et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Penetrator reliability investigation and design exploration : from conventional design processes to innovative uncertainty-capturing algorithms.

Description: This project focused on research and algorithmic development in optimization under uncertainty (OUU) problems driven by earth penetrator (EP) designs. While taking into account uncertainty, we addressed three challenges in current simulation-based engineering design and analysis processes. The first challenge required leveraging small local samples, already constructed by optimization algorithms, to build effective surrogate models. We used Gaussian Process (GP) models to construct these surrog… more
Date: November 1, 2006
Creator: Martinez-Canales, Monica L.; Heaphy, Robert; Gramacy, Robert B.; Taddy, Matt; Chiesa, Michael L.; Thomas, Stephen W. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Assessment of Current Process Modeling Approaches to Determine Their Limitations, Applicability and Developments Needed for Long-Fiber Thermoplastic Injection Molded Composites

Description: This report describes the status of the current process modeling approaches to predict the behavior and flow of fiber-filled thermoplastics under injection molding conditions. Previously, models have been developed to simulate the injection molding of short-fiber thermoplastics, and an as-formed composite part or component can then be predicted that contains a microstructure resulting from the constituents’ material properties and characteristics as well as the processing parameters. Our object… more
Date: November 30, 2006
Creator: Nguyen, Ba Nghiep; Holbery, Jim; Smith, Mark T.; Kunc, Vlastimil; Norris, Robert E.; Phelps, Jay et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Helium bubble linkage and the transition to rapid He release in aging Pd tritide.

Description: A model is presented for the linking of helium bubbles growing in aging metal tritides. Stresses created by neighboring bubbles are found to produce bubble growth toward coalescence. This process is interrupted by the fracture of ligaments between bubble arrays. The condition for ligament fracture percolates through the material to reach external surfaces, leading to material micro-cracking and the release of helium within the linked-bubble cluster. A comparison of pure coalescence and pure fra… more
Date: February 1, 2006
Creator: Cowgill, Donald F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Fundamentals of reservoir surface energy as related to surface properties, wettability, capillary action, and oil recovery from fractured reservoirs by spontaneous imbibition

Description: The objective of this project is to increase oil recovery from fractured reservoirs through improved fundamental understanding of the process of spontaneous imbibition by which oil is displaced from the rock matrix into the fractures. Spontaneous imbibition is fundamentally dependent on the reservoir surface free energy but this has never been investigated for rocks. In this project, the surface free energy of rocks will be determined by using liquids that can be solidified within the rock pore… more
Date: June 8, 2006
Creator: Morrow, Norman R.; Fischer, Herbert; Li, Yu; Mason, Geoffrey; Ruth, Douglas; Seth, Siddhartha et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modeling the Effects of Crevice Former, Particulates , and the Evolving Surface Profile in Crevice Corrosion

Description: Crevice corrosion may initiate in confined regions due to transport limitations, followed by an accumulation of a highly corrosive chemistry, capable of dissolving the metal. The metal and the crevice former surface roughness, the presence of particulates under the crevice former and the accumulation of solid corrosion products at the corroding site would significantly affect the current and potential distribution at the anode by increasing the ohmic potential drop. Most crevice corrosion model… more
Date: December 21, 2006
Creator: Agarwal, A. S.; Landau, U.; Shan, X. & Payer, J. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hydrogen Production via a Commercially Ready Inorganic Membrane Reactor Semi-Annual Technical Progress Report: April-September 2006

Description: In the last report, we covered the experimental verification of the mathematical model we developed for WGS-MR, specifically in the aspect of CO conversion ratio, and the effect of the permeate sweep. Bench-top experimental study has been continuing in this period to verify the remaining aspects of the reactor performance, including hydrogen recovery ratio, hydrogen purity and CO contaminant level. Based upon the comparison of experimental vs simulated results in this period along with the resu… more
Date: September 30, 2006
Creator: Liu, Paul K. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

SINGLE-TRANSVERSE SPIN ASYMMETRIES

Description: We give a brief overview of some of the recent results on single-transverse spin asymmetries, highlighting in particular progress in theoretical understanding.
Date: October 2, 2006
Creator: VOGELSANG, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Computaional Modeling of the Stability of Crevice Corrosion of Wetted SS316L

Description: The stability of localized corrosion sites on SS 316L exposed to atmospheric conditions was studied computationally. The localized corrosion system was decoupled computationally by considering the wetted cathode and the crevice anode separately and linking them via a constant potential boundary condition at the mouth of the crevice. The potential of interest for stability was the repassivation potential. The limitations on the ability of the cathode that are inherent due to the restricted geome… more
Date: April 17, 2006
Creator: Cui, F.; Presuel-Moreno, F.J. & Kelly, R.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Geomechanical Performance of Hydrate-Bearing Sediments in Offshore Environments

Description: The main objective of this study is to develop the necessary 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 is on the determination of the envelope of hydrate stability under conditions typical of those related to the construction and operation of offshore platforms. To achieve this objective, we have developed a robust numerical simulator of hyd… more
Date: December 31, 2006
Creator: Holditch, Stephen A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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