Computation of self-consistent 2-D MHD with neutral-beam and bootstrap currents in elongated plasmas (open access)

Computation of self-consistent 2-D MHD with neutral-beam and bootstrap currents in elongated plasmas

The observation of substantial current drive from neutral beam injection (NBI) in TFTR, JET and DIII-D has led to renewed interest in a steady state, non-inductively driven tokamak. The discovery of apparently considerable neoclassical (bootstrap) current in TFTR, makes a steady state device even more attractive since the bootstrap portion of the current could be obtained without additional power input. Motivated by these results, we have developed a code, ACCOME, which self-consistently computes the 2-D MHD equilibrium with the current driven by neutral beams, bootstrap and the electric field. In this paper we first describe some details of the code in the next section and in the subsequent section show some applications to DIII-D and to a possible ITER design.
Date: April 5, 1983
Creator: Devoto, R. S.; Tani, K. & Azumi, M.
System: The UNT Digital Library
Formation of H/sup -/ by charge transfer in alkaline-earth vapors (open access)

Formation of H/sup -/ by charge transfer in alkaline-earth vapors

Progress since the last symposium on the study of H/sup -/ formation by charge transfer in alkaline-earth vapors is reported. High yields are obtained at low energies, in agreement with theoretical predictions.
Date: December 5, 1983
Creator: Schlachter, A.S. & Morgan, T.J.
System: The UNT Digital Library
Shiva automatic pinhole alignment (open access)

Shiva automatic pinhole alignment

This paper describes a computer controlled closed loop alignment subsystem for Shiva, which represents the first use of video sensors for large laser alignment at LLNL. The techniques used on this now operational subsystem are serving as the basis for all closed loop alignment on Nova, the 200 terawatt successor to Shiva.
Date: September 5, 1980
Creator: Suski, G.J.
System: The UNT Digital Library
Time resolution performance studies of contemporary high speed photomultipliers (open access)

Time resolution performance studies of contemporary high speed photomultipliers

The time resolution capabilities of prototype microchannel plate and static crossed-field photomultipliers have been investigated. Measurements were made of electron transit time, rise time, time response, single photoelectron time spread and multiphotoelectron time spread for LEP HR350 proximity focused high gain curved microchannel plate and VPM-154A/1.6L static crossed-field photomultipliers. The experimental data have been compared with results obtained with conventionally designed RCS 8850 and C31024 high speed photomultipliers. Descriptions are given of both the measuring techniques and the measuring systems.
Date: October 5, 1977
Creator: Leskovar, B. & Lo, C.C.
System: The UNT Digital Library
Three-dimensional thermal analysis of a baseline spent fuel repository (open access)

Three-dimensional thermal analysis of a baseline spent fuel repository

A three-dimensional thermal analysis has been performed using finite difference techniques to determine the near-field response of a baseline spent fuel repository in a deep geologic salt medium. A baseline design incorporates previous thermal modeling experience and OWI recommendations for areal thermal loading in specifying the waste form properties, package details, and emplacement configuration. The base case in this thermal analysis considers one 10-year old PWR spent fuel assembly emplaced to yield a 36 kw/acre (8.9 w/m/sup 2/) loading. A unit cell model in an infinite array is used to simplify the problem and provide upper-bound temperatures. Boundary conditions are imposed which allow simulations to 1000 years. Variations studied include a comparison of ventilated and unventilated storage room conditions, emplacement packages with and without air gaps surrounding the canister, and room cool-down scenarios with ventilation following an unventilated state for retrieval purposes. At this low power level ventilating the emplacement room has an immediate cooling influence on the canister and effectively maintains the emplacement room floor near the temperature of the ventilating air. The annular gap separating the canister and sleeve causes the peak temperature of the canister surface to rise by 10/sup 0/F (5.6/sup 0/C) over that from a …
Date: June 5, 1980
Creator: Altenbach, T.J. & Lowry, W.E.
System: The UNT Digital Library
Axicell MFTF-B superconducting-magnet system (open access)

Axicell MFTF-B superconducting-magnet system

The Axicell MFTF-B magnet system will provide the field environment necessary for tandem mirror plasma physics investigation with thermal barriers. The performance of the device will stimulate DT to achieve energy break-even plasma conditions. Operation will be with deuterium only. There will be 24 superconducting coils consisting of 2 sets of yin-yang pairs, 14 central-cell solenoids, 2 sets of axicell mirror-coil pairs, and 2 transition coils between the axicell mirror coil-pairs and the yin-yang coils. This paper describes the progress in the design and construction of MFTF-B Superconducting-Magnet System.
Date: May 5, 1982
Creator: Wang, S. T.; Bulmer, R.; Hanson, C.; Hinkle, R.; Kozman, T.; Shimer, D. et al.
System: The UNT Digital Library
Chemiluminescence from the reaction of Ba /sup 3/D with nitric oxide (open access)

Chemiluminescence from the reaction of Ba /sup 3/D with nitric oxide

The reaction of laser excited Ba*(/sup 3/D) states with nitric oxide is presented. BaO product is not detected, although the channel is thermodynamically open, and instead chemiluminescence is observed. Experiments which suggest that radiative recombination, Ba + NO ..-->.. BaNO* ..-->.. BaNO, is the observed reaction channel will also be presented.
Date: January 5, 1977
Creator: Johnson, S. A.; Solarz, R. W.; Dubrin, J. W. & Brotzmann, R.
System: The UNT Digital Library
Inertial fusion research at Lawrence Livermore National Laboratory: program status and future applications (open access)

Inertial fusion research at Lawrence Livermore National Laboratory: program status and future applications

The objectives of the Lawrence Livermore National Laboratory (LLNL) Laser Fusion Program are to understand and develop the science and technology required to utilize inertial confinement fusion (ICF) for both military and commercial applications. The results of recent experiments are described. We point out the progress in our laser studies, where we continue to develop and test the concepts, components, and materials for present and future laser systems. While there are many potential commercial applications of ICF, we limit our discussions to electric power production.
Date: June 5, 1986
Creator: Meier, W. R. & Hogan, W. J.
System: The UNT Digital Library
Holographic and acoustic emission evaluation of pressure vessels (open access)

Holographic and acoustic emission evaluation of pressure vessels

Optical holographic interfereometry and acoustic emission monitoring were simultaneously used to evaluate two small, high pressure vessels during pressurization. The techniques provide pressure vessel designers with both quantitative information such as displacement/strain measurements and qualitative information such as flaw detection. The data from the holographic interferograms were analyzed for strain profiles. The acoustic emission signals were monitored for crack growth and vessel quality.
Date: March 5, 1980
Creator: Boyd, D.M.
System: The UNT Digital Library
Cryopumping system for TFTR neutral beam injectors (open access)

Cryopumping system for TFTR neutral beam injectors

The cryocondensation pumping system for the TFTR neutral beam injectors is described. Topics include hardware design, differential pumping and beam loss, operational modes, and response to massive vacuum breaks.
Date: October 5, 1977
Creator: Valby, L.E.
System: The UNT Digital Library
Application of digital image analysis techniques to the Geyser's data and topography (open access)

Application of digital image analysis techniques to the Geyser's data and topography

This paper describes the results of digital image analysis and techniques applied to acoustic sounder data and topographic relief in the Geyser's region. The two dimensional fast Fourier transform (2DFFT) represents the spacial variability of a photographic image. The spacial variability of topography in complex terrain can be represented in this way and insight into degree of complexity and dominating spacial wavelengths can be gained. This was performed for a 16 km square digitized topographic map of the Geyser's region with 63.5 m resolution. It was also of interest to compare facsimile recordings of acoustic sounder data to optical turbulence measurements.
Date: May 5, 1980
Creator: Porch, W.M.
System: The UNT Digital Library
Mechanisms of defect production and atomic mixing in high energy displacement cascades: A molecular dynamics study (open access)

Mechanisms of defect production and atomic mixing in high energy displacement cascades: A molecular dynamics study

We have performed molecular dynamics computer simulation studies of displacement cascades in Cu at low temperature. For 25 keV recoils we observe the splitting of a cascade into subcascades and show that cascades in Cu may lead to the formation of vacancy and interstitial dislocation loops. We discuss a new mechanism of defect production based on the observation of interstitial prismatic dislocation loop punching from cascades at 10 K. We also show that below the subcascade threshold, atomic mixing in the cascade is recoil-energy dependent and obtain a mixing efficiency that scales as the square root of the primary recoil energy. 44 refs., 12 figs.
Date: June 5, 1991
Creator: Diaz de la Rubia, T. & Guinan, M.W.
System: The UNT Digital Library
Development of an x-ray framing camera (open access)

Development of an x-ray framing camera

We are presently developing an ultrafast x-ray framing camera, to be used in laser fusion experiments on the NOVA facility at LLNL. The framing camera will provide high-fidelity images with frame durations of less than 100 ps. The first prototype camera will generate a single image approximately one square centimeter in area, with a spatial resolution of approx.30 microns at the image plane. Coupling the framing camera to a 22 x Wolter x-ray microscope will provide resolution at the target of approx.2 microns. The camera will be optically triggered using a laser pulse that is synchronous with the NOVA driver beams.
Date: March 5, 1986
Creator: Stearns, D.G.; Wiedwald, J.; Cook, B.M. & Hanks, R.
System: The UNT Digital Library
Recent developments in nuclear reaction theories and calculations (open access)

Recent developments in nuclear reaction theories and calculations

A brief review is given of some recent developments in the fields of optical model potentials; level densities; and statistical model, precompound, and direct reaction codes and calculations. Significant developments have occurred in all of these fields since the 1977 Conference on Neutron Cross Sections, which will greatly enhance the ability to calculate high-energy neutron-induced reaction cross sections in the next few years. 11 figures, 3 tables.
Date: May 5, 1980
Creator: Gardner, D. G.
System: The UNT Digital Library
Low-temperature hydrothermal resource evaluation (open access)

Low-temperature hydrothermal resource evaluation

The objectives of testing low-temperature hydrothermal wells are to characterize well response to production (injection), determine resource characteristics and project reservoir longevity. Testing procedures and analysis techniques differ in some respects from proven procedures in the oil and gas and ground water fields. Some basic definitions and standard techniques necessary for the evaluation of a fluid resource in an intergranular permeable reservoir are presented. Problems particular to a non-ideal thermal resource are outlined and some analytical techniques are discussed.
Date: May 5, 1980
Creator: Goldman, D.
System: The UNT Digital Library
Nickel--chromium strain gages for cryogenic stress analysis of superconducting structures in high magnetic fields (open access)

Nickel--chromium strain gages for cryogenic stress analysis of superconducting structures in high magnetic fields

Evaluation and calibration measurements were performed on commercial nickel-chromium metal-foil strain gages in a high-magnetic-field (12 T), liquid-helium (4.2 K) environment. The purpose was to fully characterize strain gages for use at cryogenic temperatures in high magnetic fields. In this study, the magnetoresistance of a number of strain gages was measured in three orthogonal directions at mechanical strain levels to 8900 ..mu..m/m. As a result, a unique calibration curve was defined for magnetoresistance strain errors that is independent of strain level and field direction to 12 T at 4.2 K. A current strain-gage application is the measurement of superconductor mechanical properties. These gages will soon be used in the stress analysis of superconducting fusion magnets during cooldown from ambient temperatures and during operation at 4.2 K with magnetic fields to 12 T.
Date: October 5, 1977
Creator: Freynik, H.S. Jr.; Roach, D.R.; Deis, D.W. & Hirzel, D.G.
System: The UNT Digital Library
Testing of the MFTF magnets (open access)

Testing of the MFTF magnets

This paper describes the cooldown and testing of the first yin-yang magnet for the Mirror Fusion Test Facility. The introduction describes the superconducting magnet; the rest of the paper explains the tests prior to and including magnet cooldown and final acceptance testing. The MFTF (originally MX) was proposed in 1976 and the project was funded for construction start in October 1977. Construction of the first large superconducting magnet set was completed in May 1981 and testing started shortly thereafter. The acceptance test procedures were reviewed in May 1981 and the cooldown and final acceptance test were done by the end of February 1982. During this acceptance testing the magnet achieved its full design current and field.
Date: May 5, 1982
Creator: Kozman, T.A.; Chang, Y. & Dalder, E.N.C.
System: The UNT Digital Library
Technology development for high-salinity geothermal resources (open access)

Technology development for high-salinity geothermal resources

An impulse turbine for Total Flow utilization of geothermal fluids was tested. Performance measurements verify the calculational model. The research goal of 70% engine efficiency remains credible. Addition of acid to the brine prevents scaling and precipitation at moderate costs. Corrosion and erosion of turbine materials for the Total Flow Process are not severe. (JB)
Date: August 5, 1977
Creator: Lundberg, A.W.
System: The UNT Digital Library
Effects of doping on hybridization gapped materials (open access)

Effects of doping on hybridization gapped materials

Doping studies are presented on three materials exhibiting hybridization gaps: Ce{sub 3}Bi{sub 4}Pt{sub 3}, U{sub 3}Sb{sub 4}Pt{sub 3}, and CeRhSb. In the case of trivalent La, Y, or Lu substituting for Ce or U, there is a suppression of the low temperature gap and an increase in the electronic specific heat, {gamma}. In the case of tetravalent Th substitutions for U there is no change in {gamma} and in the case of tetravalent Zr substitution for Ce in CeRhSb, there is an enhanced semiconductor-like behavior in the electrical resistance. These results are discussed in the light of a simple model of hybridization gapped systems. 12 refs., 3 figs.
Date: June 5, 1991
Creator: Canfield, P. C.; Thompson, J. D.; Hundley, M. F.; Lacerda, A. & Fisk, Z.
System: The UNT Digital Library
Strain-critical current data for large multifilament Nb/sub 3/Sn conductors (open access)

Strain-critical current data for large multifilament Nb/sub 3/Sn conductors

Strain-critical current measurements of monolithic, multifilament Nb/sub 3/Sn conductors are extended to larger conductors carrying approximately 3.5 kA at 12 T. Measurements were made under pure tension up to 0.9 percent strain and under combined tensile (up to 0.36 percent) and bending (+-0.53 percent) strain. Our results came close to those obtained previously on smaller (1 to 2 kA) conductors. These latest data served as our basis to design a prototype 5-kA, 12-T conductor for a 40-cm-bore magnet.
Date: October 5, 1977
Creator: Deis, D.W.; Cornish, D.N.; Hirzel, D.G. & Rosdahl, A.R.
System: The UNT Digital Library
New Evidence From Soudan 1 for Underground Muons Associated With Cygnus X-3 (open access)

New Evidence From Soudan 1 for Underground Muons Associated With Cygnus X-3

The Soudan 1 experiment has obtained additional evidence for underground muons associated with the x-ray pulsar Cygnus X-3. We report the preliminary analysis of data recorded during the October 1985 radio outburst of Cygnus X-3, which show a significant excess of muons for a narrow range of Cygnus X-3 phases.
Date: June 5, 1986
Creator: Ayres, D. S.
System: The UNT Digital Library
Ion beam and defect-related research in the Solid State Division. [LiNbO/sub 3/, Al/sub 2/O/sub 3/] (open access)

Ion beam and defect-related research in the Solid State Division. [LiNbO/sub 3/, Al/sub 2/O/sub 3/]

This paper contains viewgraphs on the topic of radiation effects of solid state materials. In particular, it elaborates on ion beam deposition of thin film structures, ion implantation damage in crystals of Al/sub 2/O/sub 3/, and ion implanted optical waveguides in LiNbO/sub 3/. (LSP)
Date: August 5, 1986
Creator: Roberto, J.B.
System: The UNT Digital Library
Engineering design of a 40 kV neutral-beam source (open access)

Engineering design of a 40 kV neutral-beam source

Sections of the 40-kV, 40-A, TMX source are shown. This module is comprised of the arc chamber and accelerator sections. The source accelerator section uses a single rectangular insulator to perform three functions: providing voltage standoff, forming the supporting structure, and acting as the vacuum wall. Both machinable glass ceramic (Corning Macor/sup TM/) and F.R.P. (Nema G-10) have been used for this insulater. In either case, the insulator is joined to the titanium base plate and extractor electrode by thermal-setting-epoxy adhesive. The parts are self jigging; the bonding is done at 120 to 130 /sup 0/C under a load of .34 MPa (50 psi).
Date: November 5, 1979
Creator: Duffy, T. J.; Molvik, A. W.; Baird, E. D.; Correll, D. L.; Munger, R. H.; Gillespie, K. et al.
System: The UNT Digital Library
Reactor Operations Management Plan (open access)

Reactor Operations Management Plan

The K-Reactor last operated in April 1988. At that time, K-Reactor was one of three operating reactors at the Savannah River Site (SRS). Following an incident in P-Reactor in August 1988, it was decided to discontinue SRS reactor operation and conduct an extensive program to upgrade operating practices and plant hardware prior to restart of any of the reactors. The K-reactor was the first of three reactors scheduled to resume production. At the present time, it is the only reactor with planned restart. WSRC assumed management of SRS on April 1, 1989. WSRC established the Safety Basis for Restart and a listing of the actions planned to satisfy the Safety Basis. In consultation with DOE, it was determined that proper management of the restart activities would require a single plan that integrated the numerous activities. The plan was entitled the Reactor Operations Management Plan and is referred to simply as the ROMP. The initial version of ROMP was produced in July of 1989. Subsequent modifications led to Revision 3 which was approved by DOE in May, 1990. Other changes were made in a formal change process, resulting in the latest version, Revision 5, being issued in October, 1990. The ROMP …
Date: December 5, 1991
Creator: Rice, P.D.
System: The UNT Digital Library