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Added mass and damping coefficients for hexagonal tube arrays

Description: An analytical investigation of the fluid coupling effects from an array of hexagonal cylindrical ducts undergoing harmonic oscillations is presented. A closed form solution for the velocity and pressure is obtained under a thin gap approximation for the case of moderate frequencies. From this solution, the usual viscous and inertial fluid coupling coefficients are easily obtained. These analytically derived coefficients indicate a strong dependence upon gap spacing and oscillating Reynolds number.
Date: August 1, 1979
Creator: Wilson, D.E.
Partner: UNT Libraries Government Documents Department

One dimensional multi-phase moving boundary problems with phases of different densities

Description: Density changes occur naturally in phase change problems. It is customary in analyzing such problems to ignore the bulk movement of material thus introduced and assume the densities to be equal. However, for one dimensional problems the complexity introduced by this bulk movement is more apparent than real. This can be demonstrated by posing the problem in local coordinates fixed in each phase. In this report we show how to define suitable moving coordinates and, using them, pose and solve a one dimensional, multi-phase Stefan problem with phases of distinct densities. This explicit solution is essentially a similarity solution in the local coordinates. However, utility of these local coordinates is not limited to problems for which similarity solutions exist. They could be used with finite element or finite difference schemes to analyze more complex problems.
Date: January 1, 1982
Creator: Wilson, D.G.
Partner: UNT Libraries Government Documents Department

Evaluation of regional effects of effluents from uranium production in New Mexico

Description: The Grants Uranium Region is a 2500 mile area of northcentral New Mexico which has produced about 40 percent of all domestic uranium, and holds over one-half of the current reserves. The increasing demand for uranium to fuel commercial nuclear power plants is resulting in rapid growth of the uranium industry and economic, social, and environmental changes are occurring. One of the environmental issues of this region is the concern for eventually unacceptable levels of air and water pollution from effluents from uranium mill tailings piles. This study addresses these potential impacts in relation to industrial environmental control practices, siting features, and other regional/temporal variables, including rates of production, locations and sizes of new mills, and population distributions.
Date: October 4, 1977
Creator: Wilson, D.W.
Partner: UNT Libraries Government Documents Department

Solar heating and cooling working fluids released to the ecosystem

Description: Gylcols, polygloycols, silicone oils, hydrocarbon oils and various corrosion inhibitors and biocides used in solar heating and cooling systems are tested and evaluated for their potential effects on soils, vegetation, and in regard to potential groundwater contamination. Experimental tests include measurement of the effects of additions of these substances to soils on soil microbial respiration, above ground vegetation, and on the mobilization of chemicals in soil water, including the test substance and any significant biodegradation products. Experimental work aims at developing the data base necessary to evaluate the environmental acceptability of the wide range of materials used for this purpose, addressing the need for development of disposal practices and the means of mitigating effects on the environment due to accidental releases.
Date: January 1, 1978
Creator: Wilson, D.W. & Miera, F.R. Jr.
Partner: UNT Libraries Government Documents Department


Description: Downhole logging and workover operations on 12-20 year old wells in several high temperature, liquid-dominated geothermal fields in New Zealand has shown that severe corrosion has commonly occurred in the production casing string where this is unprotected by larger diameter casings. To date corrosion products from only one well have been examined in detail. These indicate that corrosion attack commences at the outer casing wall and continues at a rate as great as 0.8mm/year. Rapid corrosion has been attributed to neutral or slightly acid high bicarbonate waters formed by the absorption of steam and gas into shallow aquifers not directly connected to the deeper, high chloride reservoir.
Date: January 22, 1985
Creator: Bixley, P.F. & Wilson, D.M.
Partner: UNT Libraries Government Documents Department

Year 2011 Gulfwide Emission Inventory Study

Description: A report assessing the potential impacts of air pollutant emissions from offshore oil and gas exploration, development, and production sources on the Outer Continental Shelf for the year 2011.
Date: November 2014
Creator: Wilson, D.; Billings, R.; Chang, R.; Perez, H. & Sellers, J.
Partner: UNT Libraries Government Documents Department

[Project Summary: The Data Quality Control and Emissions Inventories of OCS Oil and Gas Production Activities in the Breton Area of the Gulf of Mexico]

Description: Report summary describing the work completed at Eastern Research Group, Inc. for 'The Data Quality Control and Emissions Inventories of OCS Oil and Gas Production Activities in the Breton Area of the Gulf of Mexico'. It includes background information on the project funding and sponsorship, goals, methodology, and findings.
Date: October 2004
Creator: Eastern Research Group, Inc.
Partner: UNT Libraries Government Documents Department

Gallium-cladding compatibility testing plan. Phases 1 and 2: Test plan for gallium corrosion tests; Revision 2

Description: This test plan is a Level-2 document as defined in the Fissile Materials Disposition Program Light-Water-Reactor Mixed-Oxide Fuel Irradiation Test Project Plan. The plan summarizes and updates the projected Phases 1 and 2 Gallium-Cladding compatibility corrosion testing and the following post-test examination. This work will characterize the reactions and changes, if any, in mechanical properties that occur between Zircaloy clad and gallium or gallium oxide in the temperature range 30--700 C.
Date: May 1, 1998
Creator: Wilson, D.F. & Morris, R.N.
Partner: UNT Libraries Government Documents Department

Mushy-zone model with an exact solution

Description: In this paper we propose a very simple model of a mushy zone which admits of an explicit solution. To our knowledge, it is the only instance where an actual observation of the mushy zone width and structure is used as a partial basis for the model definition. The model rests upon two unknown parameters. The first determines the relation between the equilibrium temperature gradient and the mushy zone width. The second depends upon the dendritic structure in the mushy zone, and is related to the solid fraction. Both can be estimated from experiments. We will limit ourselves to defining the model, presenting its closed form solution, and giving tables from which the solution can be found explicitly. It is shown that in most cases the predicted mushy zone is of very negligible importance.
Date: April 1, 1982
Creator: Solomon, A. D.; Wilson, D. G. & Alexiades, V.
Partner: UNT Libraries Government Documents Department

High-temperature thermal storage systems for advanced solar receivers materials selections

Description: Advanced space power systems that use solar energy and Brayton or Stirling heat engines require thermal energy storage (TES) systems to operate continuously through periods of shade. The receiver storage units, key elements in both Brayton and Stirling systems, are designed to use the latent heat of fusion of phase-change materials (PCMs). The power systems under current consideration for near-future National Aeronautics and Space Administration space missions require working fluid temperatures in the 1100 to 1400 K range. The PCMs under current investigation that gave liquidus temperatures within this range are the fluoride family of salts. However, these salts have low thermal conductivity, which causes large temperature gradients in the storage systems. Improvements can be obtained, however, with the use of thermal conductivity enhancements or metallic PCMs. In fact, if suitable containment materials can be found, the use of metallic PCMs would virtually eliminate the orbit associated temperature variations in TES systems. The high thermal conductivity and generally low volume change on melting of germanium and alloys based on silicon make them attractive for storage of thermal energy in space power systems. An approach to solving the containment problem, involving both chemical and physical compatibility, preparation of NiSi/NiSi{sub 2}, and initial results for containment of germanium and NiSi/NiSi{sub 2}, are presented. 7 refs., 10 figs., 4 tabs.
Date: September 1, 1990
Creator: Wilson, D.F.; DeVan, J.H. & Howell, M.
Partner: UNT Libraries Government Documents Department

Bibliography on moving boundary problems with key word index

Description: This bibliography concentrates mainly on time-dependent moving-boundary problems of heat and mass transfer. The bibliography is in two parts, a list of the references ordered by last name of the first author and a key word index to the titles. Few references from before 1965 are included. (RWR)
Date: October 1, 1979
Creator: Wilson, D.G.; Solomon, A.D. & Trent, J.S.
Partner: UNT Libraries Government Documents Department

Analysis of mixed oxide fuel irradiated in EBR-II: measured vs. predicted burnup

Description: The calculation of burnup in mixed-oxide fuel pins irradiated in EBR-II is shown to agree with burnup measured by postirradiation radiochemical analysis. The mean percent deviation is 0.12% with a variance of 2.49%. This gives a high level of confidence that HIST, which uses 91% of the nominal EBR-II power, provides an accurate estimate of burnup.
Date: May 1, 1978
Creator: Scott, L.D.; Dutt, D.S. & Wilson, D.R.
Partner: UNT Libraries Government Documents Department

Indirectly driven targets for ignition

Description: Both Los Alamos and Lawrence Livermore Laboratories have studied capsule and laser driven target designs for the National Ignition Facility. The current hohlraum design is a 2.76mm radius, 9.5mm long gold cylinder with 1.39mm radius laser entrance holes covered by 1{mu}m thick plastic foils. Laser beams strike the inside cylinder wall from two separate cones with a peak power less than 400 TW. The problem with a pressure pulse caused by wall plasma stagnating on axis has been overcome by filling the hohlraum with gas. Currently this is equi-molar hydrogen-helium gas at 0.83 mg/cc density. One capsule uses a 160 {mu}m plastic ablator doped with oxygen and bromine surrounding an 80 {mu}m thick DT ice layer with an inner radius of 0.87 mm. Los Alamos integrated calculations of the hohlraum and this capsule using 1.4 MJ of laser energy achieve yields of 4.9 MJ using LTE atomic physics, and 3.5 MJ with non-LTE. This confirms Livermore calculations of ignition. For radiation driven implosions, a beryllium ablator offers a viable alternative to plastic. It is strong enough to contain high DT pressures. Copper, soluble at required levels, is an excellent dopant to add opacity. A beryllium capsule with a 155 {mu}m thick ablator doped with 0.9 atom % copper, and the same inner dimensions as the plastic capsule, placed in a similar hohlraum , yields 6.9 MJ with LTE. Although these calculations show the designs are sensitive, they add to the confidence that NIF can achieve ignition. Using their best integrated calculations which are not yet fully optimized, they confirm Livermore calculations of ignition with a plastic capsule, and have added an alternate capsule design with a beryllium ablator.
Date: December 31, 1994
Creator: Wilson, D. C. & Krauser, W. J.
Partner: UNT Libraries Government Documents Department

[Studies of the genetic regulation of the Thermomonospora cellulase complex]. Progress report, June 1, 1990--January 10, 1992

Description: The goals of this project are to determine the molecular mechanisms regulating cellulose synthesis in the soil bacterium Thermomonosporafusca and to determine the molecular mechanism by which T.fusca cellulases degrade crystalline cellulose. We have determined a structure for the T.fusca E{sub 2} catalytic subunit (E{sub 2}-30) by x-ray crystallography. This structure is quite similar to that of T.reesei CBHU but there are a number of differences. One is that the E{sub 2} active site is in a cleft while that of CBHII is in a tunnel. This is an expected result since E{sub 2} is an endocellulase. Large amounts of homogenous E{sub 5} catalytic subunit have been prepared and attempts to crystallize it are underway. Crystals of E{sub 2}-30 were soaked in cellobiose and modified crystals detracted well, however difference Fourier analysis showed many changes, so that we could not localize cellobiose in the 3-D structure of E{sub 2}-30. This implies that binding of cellobiose causes a significant change in the structure of E{sub 2}-30. The stereochemistry of the cleavage catalyzed by E{sub l}, E{sub 2} and E{sub 5} was determined in collaboration with Dr. Stephen Withers and E{sub 1} and 2 inverted the glycoside linkage while E{sub 5} does not. The entire E{sub l} and E{sub 4} genes have been induced into Streptomyces lividans where they are expressed at a high level and the E{sub l} and E{sub 4} are completely secreted into the medium. Studies on the synergism between the exocellulase E{sub 3} and the endocellulases E{sub 2} or E{sub 5} show that both exo and endocellulase activities are stimulated when they are assayed together.
Date: August 1, 1992
Creator: Wilson, D. B.
Partner: UNT Libraries Government Documents Department

Characterization and Suppression of the Electromagnetic Interference Induced Phase Shift in the JLab FEL Photo - Injector Advanced Drive Laser System

Description: The drive laser for the photo-cathode gun used in the JLab Free Electron Laser (FEL) facility had been experiencing various phase shifts on the order of tens of degrees (>20{sup o} at 1497 MHz or >40ps) when changing the Advanced Drive Laser (ADL) [2][3][4] micro-pulse frequencies. These phase shifts introduced multiple complications when trying to setup the accelerator for operation, ultimately inhibiting the robustness and overall performance of the FEL. Through rigorous phase measurements and systematic characterizations, we determined that the phase shifts could be attributed to electromagnetic interference (EMI) coupling into the ADL phase control loop, and subsequently resolved the issue of phase shift to within tenths of a degree (<0.5{sup o} at 1497 MHz or <1ps). The diagnostic method developed and the knowledge gained through the entire process will prove to be invaluable for future designs of similar systems.
Date: September 1, 2011
Creator: F. G. Wilson, D. Sexton, S. Zhang
Partner: UNT Libraries Government Documents Department

[Project Summary: Gulfwide Emission Inventory for the Regional Haze and Ozone Modeling Effort]

Description: Summary describing the work completed at Eastern Research Group, Inc. for 'Gulfwide Emission Inventory for the Regional Haze and Ozone Modeling Effort'. It includes background information on the project funding and sponsorship, goals, methodology, and findings.
Date: October 2004
Creator: Eastern Research Group, Inc.
Partner: UNT Libraries Government Documents Department