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A 2-D Pore-Network Model of the Drying of Single-Component Liquids in Porous Media (open access)

A 2-D Pore-Network Model of the Drying of Single-Component Liquids in Porous Media

The drying of liquid-saturated porous media is typically approaching using macroscopic continuum models involving phenomenological coefficients. Insight on these coefficients can be obtained by a more fundamental study at the pore- and pore-network levels. In this report, a model based on pore-network representation of porous media that accounts for various process at the pore-scale is presented. These include mass transfer by advection and diffusion in the gas phase, viscous flow in liquid and gas phases and capillary effects at the gas-liquid menisci in the pore throats.
Date: January 20, 2000
Creator: Yortsos, Yanic C.; Yiotis, A. G.; Stubos, A. K. & Boundovis, A. G.
Object Type: Report
System: The UNT Digital Library
2-D Reflectometer Modeling for Optimizing the ITER Low-field Side Reflectometer System (open access)

2-D Reflectometer Modeling for Optimizing the ITER Low-field Side Reflectometer System

The response of a low-field side reflectometer system for ITER is simulated with a 2?D reflectometer code using a realistic plasma equilibrium. It is found that the reflected beam will often miss its launch point by as much as 40 cm and that a vertical array of receiving antennas is essential in order to observe a reflection on the low-field side of ITER.
Date: September 2, 2005
Creator: Kramer, G. J.; Nazikian, R.; Valeo, E. J.; Budny, R. V.; Kessel, C. & Johnson, D.
Object Type: Report
System: The UNT Digital Library
A 2-D Self-Consistent DSMC Model for Chemically Reacting Low Pressure Plasma Reactors (open access)

A 2-D Self-Consistent DSMC Model for Chemically Reacting Low Pressure Plasma Reactors

This paper will focus on the methodology of using a 2D plasma Direct Simulation Monte Carlo technique to simulate the species transport in an inductively coupled, low pressure, chemically reacting plasma system. The pressure in these systems is typically less than 20 mtorr with plasma densities of approximately 10{sup 17} {number_sign}/m{sup 3} and an ionization level of only 0.1%. This low ionization level tightly couples the neutral, ion, and electron chemistries and interactions in a system where the flow is subsonic. We present our strategy and compare simulation results to experimental data for Cl{sub 2} in a Gaseous Electronics Conference (GEC) reference cell modified with an inductive coil.
Date: June 17, 1999
Creator: Bartel, Timothy J.; Economou, Demetre & Johannes, Justine E.
Object Type: Article
System: The UNT Digital Library
2-D Simulations of Drainage Winds and Diffusion Compared to Observations (open access)

2-D Simulations of Drainage Winds and Diffusion Compared to Observations

A vertically integrated dynamical drainage flow model is developed from conservation equations for momentum and mass in a terrain-following coordinate system. Wind fields from the dynamical model drive a Monte Carlo transport and diffusion model. The model needs only topographic data, an Eulerian or Lagrangian time scale and a surface drag coefficient for input data, and can be started with a motionless atmosphere. Model wind and diffusion predictions are compared to observations from the rugged Geysers CA area. Model winds generally agree with observed surface winds, and in some cases may give better estimates of area-averaged flow than point observations. Tracer gas concentration contours agree qualitatively with observed contours, and point predictions of maximum concentrations were correctly predicted to within factors of 2 to 10. Standard statistical tests of model skill showed that the accuracy of the predictions varied significantly from canyon to canyon in the Geysers are a. Model wind predictions are also compared to observations from the Savannah River Plant of SC which has gently rolling terrain. The model correctly simulated the slower development of drainage winds and slower deepening of the drainage layer in the Savannah River Valley, relative to the Geysers CA simulations. The SC simulations …
Date: May 29, 2001
Creator: Garrett, A. J.
Object Type: Article
System: The UNT Digital Library
2-D skin-current toroidal-MHD-equilibrium code (open access)

2-D skin-current toroidal-MHD-equilibrium code

A two-dimensional, toroidal, ideal MHD skin-current equilibrium computer code is described. The code is suitable for interactive implementation on a minicomptuer. Some examples of the use of the code for design and interpretation of toroidal cusp experiments are presented.
Date: September 1, 1982
Creator: Feinberg, B.; Niland, R. A.; Coonrod, J. & Levine, M. A.
Object Type: Report
System: The UNT Digital Library
2-D time evolution of T/sub e/ during sawtooth crash based on fast ECE (electron cyclotron emission) measurements on TFTR (open access)

2-D time evolution of T/sub e/ during sawtooth crash based on fast ECE (electron cyclotron emission) measurements on TFTR

Electron cyclotron emission measurements taken at 20 locations in the horizontal midplane during a sawtooth crash have been analysed based on the assumption of fast rigid rotation of the plasma. Due to this fast rotation (approx.100..mu..sec), which remains fairly constant throughout the sawtooth crash, we have been able to make time-to-space reconstructions of half the poloidal plane using points which are separated in time by not more than 40..mu..sec. The existence of a temperature flattening in the precursor phase, which we interpret as an m = 1 temperature island, is clearly demonstrated, and its location and width agree well with local emissivity measurements from soft x-ray tomography viewing the same poloidal plane. The rotating temperature island in the precursor phase, the outward movement of the region of high T/sub c/ during the crash phase, and the shape of T/sub e/ during the crash phase, and the shape of T/sub e/ distribution after the crash during the successor phase have all been documented in a time sequence of color contours. 4 refs., 10 figs.
Date: December 1, 1988
Creator: Kuo-Petravic, G.
Object Type: Report
System: The UNT Digital Library
2-D Tomography With Bolometry in DIII-D (open access)

2-D Tomography With Bolometry in DIII-D

We have installed a 48-channel platinum-foil bolometer system on DIII-D achieve better spatial and temporal resolution of the radiated power in diverted discharges. Two 24-channel arrays provide complete plasma coverage with optimized views of the divertor. We have measured the divertor radiation profile for a series of radiative divertor and power balance experiments. We observe a rapid change in the magnitude and distribution of divertor radiation with heavy gas puffing. Unfolding the radiation profile with only two views requires us to treat the core and divertor radiation separately. The core radiation is fitted to a function of magnetic flux and is then subtracted from the divertor viewing chords. The divertor profile is then fit to a 2-D spline as a function of magnetic flux and poloidal angle.
Date: July 1, 1994
Creator: Leonard, A. W.; Meyer, W. H.; Geer, B.; Behne, D. M. & Hill, D. N.
Object Type: Article
System: The UNT Digital Library
S = -2 dibaryons and hypernuclei (open access)

S = -2 dibaryons and hypernuclei

Future prospects for the exploration of doubly strange hypernuclear systems are evaluated. Such systems may be produced via the double strangeness exchange reactions (K/sup -/,K/sup +/) or (K/sup -/,K/sup 0/) on nuclear targets. Theoretical estimates are given of the formation cross sections for Xi/sup -/ hypernuclear states via the one-step K/sup -/p ..-->.. K/sup +/Xi/sup -/ process, or discrete states of the ..lambda lambda.. hypernucleus in the two step reaction K/sup -/p ..-->.. ..pi../sup 0/..lambda.. followed by ..pi../sup 0/p ..-->.. K/sup +/..lambda... Recently, there has been much discussion of six quark (dibaryon) states in the Bag Model. Arguments are given which indicate that the (K/sup -/,K/sup +/) reaction on light nuclear targets (ex. /sup 3/He) affords a very promising way of producing the lowest-lying S = -2 dibaryon (called the H).
Date: January 1, 1982
Creator: Dover, C.B.
Object Type: Article
System: The UNT Digital Library
2-Dimensional studies of the disk-and-washer and side-coupled resonant cavity structures (open access)

2-Dimensional studies of the disk-and-washer and side-coupled resonant cavity structures

The work done consists of three parts: optimizing the disk-and-washer (DAW) structure at ..beta.. = 0.5662 corresponding to E = 200 MeV; comparing the DAW structure with the side-coupled (SCS) structure at various values of beta, ranging from ..beta.. = 0.4569 and E = 116 MeV to ..beta.. = 0.7131 and E = 400 MeV; and re-optimizing the DAW structure at ..beta.. = 0.7131. 4 refs., 51 figs., 41 tabs.
Date: December 1, 1987
Creator: Larry, L.D. Jr.
Object Type: Report
System: The UNT Digital Library

2-Fold G.M. Coincidence Unit

Report containing a diagram of a coincidence unit, outlining resistor values and other technical specifications.
Date: 1947
Creator: U.S. Atomic Energy Commission
Object Type: Technical Drawing
System: The UNT Digital Library
A 2-GHz Rectangular Corrugated Horn (open access)

A 2-GHz Rectangular Corrugated Horn

We have designed, constructed and tested a large, rectangular horn antenna with a center frequency of 2.0 GHz, corrugated on the E-plane walls, made out of aluminum sheet. A new technique has been developed to solder thin aluminum strips onto the back plane to form the corrugations. The radiation beam pattern shows half-power beamwidths of 12{sup 0} and 14{sup 0} in the H and E planes respectively, and side lobe response below -40 dB at angles greater than 50{sup 0} from horn axis. The measured return loss is less than -20 dB (VSWR < 1.22) between 1.7 and 2.3 GHz; insertion loss is less than 0.15 dB.
Date: October 1, 1991
Creator: Bersanelli, M.; Bensadoun, M.; De Amici, Giovanni; Limon, M.; Smoot, George F.; Tanaka, S. et al.
Object Type: Article
System: The UNT Digital Library
2 Hz, 30 T Split Pulse Water Cooled Magnet for Neutron Scattering Experiments (Materials Characterization and Design Options) (open access)

2 Hz, 30 T Split Pulse Water Cooled Magnet for Neutron Scattering Experiments (Materials Characterization and Design Options)

None
Date: August 26, 1997
Creator: Eyssa, Y. M.; Walsh, R. P.; Miller, J. R.; Miller, G. E.; Pernambuco-Wise, P.; Bird, M. D. et al.
Object Type: Report
System: The UNT Digital Library
2 Letters from concerned citizens in response to the recommendation regarding the Defense Office of Hearings and Appeals in Fort Meade (open access)

2 Letters from concerned citizens in response to the recommendation regarding the Defense Office of Hearings and Appeals in Fort Meade

Community Correspondence - 2 Letters from concerned citizens in response to the recommendation regarding the Defense Office of Hearings and Appeals in Fort Meade
Date: July 30, 2005
Creator: unknown
Object Type: Legal Document
System: The UNT Digital Library
2 letters from George H. Newman in response to the recommendations regarding Eglin Air Force Base (open access)

2 letters from George H. Newman in response to the recommendations regarding Eglin Air Force Base

Community Correspondence - 2 letters from George H. Newman in response to the recommendations regarding Eglin Air Force Base
Date: July 30, 2005
Creator: Newman, George H. Major
Object Type: Letter
System: The UNT Digital Library
A 2-Liter, 2000 MPa Air Source for the Radiatively Driven Hypersonic Wind Tunnel (open access)

A 2-Liter, 2000 MPa Air Source for the Radiatively Driven Hypersonic Wind Tunnel

The A2 LITE is a 2 liter, 2000 MPa, 750 K ultra-high pressure (UHP) vessel used to demonstrate UHP technology and to provide an air flow for wind tunnel nozzle development. It is the largest volume UHP vessel in the world. The design is based on a 100:1 pressure intensification using a hydraulic ram as a low pressure driver and a three-layer compound cylinder UHP section. Active control of the 900 mm piston stroke in the 63.5 mm bore permits pressure-time profiles ranging from static to constant pressure during flow through a 1 mm throat diameter nozzle for 1 second.
Date: May 30, 2002
Creator: Costantino, M & Lofftus, D
Object Type: Article
System: The UNT Digital Library
N = 2 Maxwell-Einstein Supergravity Theories: Their Compact and Non-Compact Gaugings and Jordan Algebras (open access)

N = 2 Maxwell-Einstein Supergravity Theories: Their Compact and Non-Compact Gaugings and Jordan Algebras

In this talk we give a review of our work on the construction and classification of N = 2 Maxwell-Einstein Supergravity theories (MESGT), study of the underlying algebraical and geometrical structure of these theories, and their compact and non-compact gaugings. We begin by summarizing our construction of the N = 2 MESGT's in five dimensions and give a geometrical interpretation to various scalar dependent quantities in the Lagrangian, based on the constraiants implied by supersymmetry. This is followed by a complete classification of the N = 2 MESGT's whose target manifolds parametrized by the scalar fields are symmetric spaces. 39 refs.
Date: January 1, 1985
Creator: Guenaydin, M.; Sierra, G. & Townsend, P.K.
Object Type: Article
System: The UNT Digital Library
2 meg-ampere prototype levitated coil for multipole fusion (open access)

2 meg-ampere prototype levitated coil for multipole fusion

The coils major diameter is 1.0 meter and it occupies a cross-section which is about 0.2 meter minor in diameter. The prototype coil will carry four times the current of the largest such magnet built to date. As a result, the peak induction in the coil is about 8 T and the stored magnetic energy will be around 3 MJ. The paper describes the proposed Nb/sub 3/SN superconductor, the quench protection system which is based on the LBL shorted secondary concept, the isochroic refrigeration storage system which stores about 5 kJ of refrigeration between 4.5/sup 0/K and 7/sup 0/K, and the persistent switch.
Date: November 1, 1979
Creator: Green, M. A. & Glueck, R.
Object Type: Article
System: The UNT Digital Library
A 2-Megawatt load for testing high voltage dc power supplies (open access)

A 2-Megawatt load for testing high voltage dc power supplies

A high power water-cooled resistive load, capable of dissipating 2 Megawatts at 95 kilovolts is being designed and built. The load utilizes wirewound resistor elements suspended inside insulating tubing contained within a pressure vessel which is supplied a continuous flow of deionized water for coolant. A sub-system of the load is composed of non-inductive resistor elements in an oil tank. Power tests conducted on various resistor types indicate that dissipation levels as high as 22 times the rated dissipation in air can be achieved when the resistors are placed in a turbulent water flow of at least 15 gallons per minute. Using this data, the load w.as designed using 100 resistor elements in a series arrangement A single-wall 316 stainless steel pressure vessel with flanged torispherical heads is built to contain the resistor assembly and deionized water. The resistors are suspended within G-11 tubing which span the cylindrical length of the vessel. These tubes are supported by G-10 baffles which also increase convection from the tubes by promoting turbulence within the surrounding water.
Date: June 1, 1993
Creator: Horan, D.; Kustom, R.; Ferguson, M. & Primdahl, K.
Object Type: Article
System: The UNT Digital Library
A 2-MeV microwave thermionic gun (open access)

A 2-MeV microwave thermionic gun

A high-gradient, S-band microwave gun with a thermionic cathode is being developed in a collaborative effort by AET, Varian, and SSRL. A prototype design using an upgraded Varian dispenser cathode mounted with thermal isolation directly in the first half-cell of a 1-1/2 cell, side-coupled, standing-wave cavity has been fabricated and is being tested. Optimization of the cavity shape and beam formation was done using SUPERFISH, MASK, and PARMELA. An overview of design details, as well as the status of in-progress beam tests, will be presented. 9 refs., 6 figs.
Date: August 1, 1989
Creator: Tanabe, E.; Borland, M.; Green, M. C.; Miller, R. H.; Nelson, L. V.; Weaver, J. N. et al.
Object Type: Article
System: The UNT Digital Library
2-mm microwave interferometer (open access)

2-mm microwave interferometer

A 2-mm microwave interferometer has been developed, and phase shift measurements have been made on the Baseball II experiment. The interferometer system employs a 140-GHz receiver for double down conversion of the plasma signal to a 60-MHz, IF frequency. The 140-GHz references signal is also down-converted and compared with the plasma signal to provide the desired phase change of the signal passing through the plasma. A feedback voltage from a 60-MHz discriminator to a voltage-controlled oscillator in the receiver provides frequency stability of the 60-MHz IF signals.
Date: March 1, 1977
Creator: Futch, A. H. & Mortensen, W. K.
Object Type: Report
System: The UNT Digital Library
2-MV electrostatic quadrupole injector for heavy-ion fusion (open access)

2-MV electrostatic quadrupole injector for heavy-ion fusion

High current and low emittance are principal requirements for heavy-ion injection into a linac driver for inertial fusion energy. An electrostatic quadrupole (ESQ) injector is capable of providing these high charge density and low emittance beams. We have modified the existing 2-MV Injector to reduce beam emittance and to double the pulse length. We characterize the beam delivered by the modified injector to the High Current Transport Experiment (HCX) and the effects of finite rise time of the extraction voltage pulse in the diode on the beam head. We demonstrate techniques for mitigating aberrations and reducing beam emittance growth in the injector.
Date: November 10, 2004
Creator: Bieniosek, F. M.; Celata, C. M.; Henestroza, E.; Kwan, J. W.; Prost, L. & Seidl, P. A.
Object Type: Article
System: The UNT Digital Library
2 MV Injector as the Elise Front-End and as an Experimental Facility (open access)

2 MV Injector as the Elise Front-End and as an Experimental Facility

We report on progress in the preparation of the 2 MV Injector at LBNL as the front-end of Elise, and as a multi-purpose experimental facility for Heavy Ion Fusion beam dynamics studies. Recent advances on the performance and understanding of the injector are described, and some of the on-going experimental activities are summarized.
Date: December 7, 1999
Creator: Yu, S. S.; Eylon, S.; Henestroza, E.; Peters, C.; Reginato, L.; Tauschwitz, A. et al.
Object Type: Report
System: The UNT Digital Library
A 2-MV multi-beam injector for heavy ion fusion (open access)

A 2-MV multi-beam injector for heavy ion fusion

Construction of a sixteen beam (0.5 A per beam) injector for use in scaled heavy ion fusion experiments is underway at LBL. The machine was designed and partially constructed at LANL. The injector is designed to use carbon arc sources which will provide 25 mA/cm/sup 2/ of extractable current density. The plasma from the arcs is confined electrostatically from drifting into the ion gun before firing the extraction pulse. The acceleration column consists of a set of aperture lenses which both transport the beam and attenuate backstreaming electrons. The acceleration column is mounted inside a 28-inch diameter brazed alumina insulating module. The high voltage for the injector is provided by an inductively loaded and graded Marx generator which resides inside a pressure vessel filled with a 65 psig mixture of 30/percent/ SF/sub 6/ and 70/percent/ N/sub 2/. Data is presented showing the performance of single and multiple carbon arc sources. Measurements show that adequate current density is available. Emittance measurements and efforts to improve emittance and reproducibility are shown. Tests with a 5-tray section of the full 18 tray generator are described showing the evolution of the generator design. 5 refs., 3 figs.
Date: June 1, 1988
Creator: Rutkowski, H. L.; Faltens, A.; Vanecek, D.; Pike, C.; Humphries, S., Jr. & Meyer, E. A.
Object Type: Article
System: The UNT Digital Library
2 MW 110 GHz ECH heating system for DIII-D (open access)

2 MW 110 GHz ECH heating system for DIII-D

A 2 MW 110 GHz ECH system using Varian 0.5 MW gyrotrons is under construction for use on the DIII-D tokamak by late 1991. Most of the components are being design and fabricated at General Atomics, including the gyrotron tanks, superconducting magnets, and transmission line. These components are intended for operation with 10 second pulses and, in the future, with 1 MW gyrotrons. 6 refs., 5 figs.
Date: September 1990
Creator: Moeller, C.; Prater, R.; Callis, R.; Remsen, D.; Doane, J.; Cary, W. et al.
Object Type: Article
System: The UNT Digital Library