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.
Object Type: Article
System: The UNT Digital Library
Application of microfabrication technology to thermionic energy conversion. Progress report 4, 1 May 1980 to 31 July 1980 (open access)

Application of microfabrication technology to thermionic energy conversion. Progress report 4, 1 May 1980 to 31 July 1980

Two applications of microfabrication technology to thermionic converters have been investigated theoretically. The first is a novel method of maintaining micron or submicron spacings over large areas (>1 cm/sup 2/), using metals of different expansion coefficients to eliminate the shear stresses on the insulating pillars separating the electrodes. The second uses low-voltage field-emission sources to create ions in a large (approx. 1 mm) interelectrode gap for space charge neutralization. The theoretical results for both these approaches are highly encouraging.
Date: September 5, 1980
Creator: Brodie, I.
Object Type: Report
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.
Object Type: Article
System: The UNT Digital Library
A Search for New Leptons with Heavy Neutrinos in e/sup +/e/sup -/ Annihilation at. sqrt. s = 29 GeV. [None] (open access)

A Search for New Leptons with Heavy Neutrinos in e/sup +/e/sup -/ Annihilation at. sqrt. s = 29 GeV. [None]

This thesis describes the results of a search for new leptons with associated heavy neutrinos. The search uses 68.1 pb/sup /minus/1/ of data taken with the TPC2..gamma.. detector at the PEP storage ring. New lepton pairs with charged lepton masses m/sub L/ < 12 GeV and mass differences in the approximate range 0.4 GeV < m/sub L/ /minus/ m/sub/nu/L/ < 2.5 GeV are excluded at the 99% confidence level. Results are also given of a study of search techniques for the region m/sub L/ < 12 GeV, m/sub L/ /minus/ m/sub ..nu..L/ < 0.4 GeV.
Date: May 5, 1988
Creator: Mathis, L. G.
Object Type: Report
System: The UNT Digital Library
Physical characterization of magmatic liquids. [Ultrasonic and Brillouin Scattering Studies of Natural and Synthetic Silicates and Oxides] (open access)

Physical characterization of magmatic liquids. [Ultrasonic and Brillouin Scattering Studies of Natural and Synthetic Silicates and Oxides]

This report describes a research project that was conducted from August 15, 1985 to February 28, 1992. The project was based on the ultrasonic studies of natural and synthetic silicate melts, and the study of Brillouin scattering of synthetic silicates and oxides. Measurements of the compressional wave velocity and attenuation can be established using the ultrasonic methods. Temperature dependences of silicates can be established by the Brillouin scattering. (MB)
Date: June 5, 1992
Creator: Manghnani, M.H.
Object Type: Report
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.
Object Type: Article
System: The UNT Digital Library
H4LM Graphite (open access)

H4LM Graphite

A commercial graphite useful in nuclear reactor construction is described. A survey of all currently available sources on chemical and physical properties was made and the information listed. Some data on cost and available sizes are also included. (auth)
Date: July 5, 1962
Creator: Merryman, R. G.; Wagner, P. & MacMillan, D. P.
Object Type: Report
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.
Object Type: Article
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.
Object Type: Article
System: The UNT Digital Library
High beta and second stability region transport and stability analysis (open access)

High beta and second stability region transport and stability analysis

This document describes ideal and resistive MHD studies of high-beta plasmas and of the second stability region. Significant progress is reported on the resistive stability properties of high beta poloidal supershot'' discharges. For these studies initial profiles were taken from the TRANSP code which is used extensively to analyze experimental data. When an ad hoc method of removing the finite pressure stabilization of tearing modes is implemented it is shown that there is substantial agreement between MHD stability computation and experiment. In particular, the mode structures observed experimentally are consistent with the predictions of the resistive MHD model. We also report on resistive stability near the transition to the second region in TFTR. Tearing modes associated with a nearby infernal mode may explain the increase in MHD activity seen in high beta supershots and which impede the realization of Q{approximately}1. We also report on a collaborative study with PPPL involving sawtooth stabilization with ICRF.
Date: September 5, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Literature review of the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on OTEC heat exchangers (open access)

Literature review of the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on OTEC heat exchangers

An investigation of available data on the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on Ocean Thermal Energy Conversion (OTEC) heat exchangers has been carried out. Pertinent oceanographic data is lacking at or near potential OTEC sites for the calculation of the degree of saturation of seawater with respect to calcium carbonate. Consequently, only ''extrapolated'' saturation values can be used. These indicate that near surface seawater is probably supersaturated, with respect to the calcium carbonate phases calcite and aragonite, at all potential OTEC sites. The deep seawater that would be brought to the surface at the potential Atlantic Ocean sites is also likely to be supersaturated with respect to calcium carbonate. The deep seawater at the potential Pacific Ocean sites may be slightly undersaturated. The fact that OTEC heat exchangers will be operating in seawater, which is supersaturated with respect to calcium carbonate, means that if nucleation of calcite or aragonite occurs on the heat exchanger surfaces, significant growth rates of calcium carbonate scale may be expected. The potential for calcium carbonate nucleation is highest at cathodic metal surface locations, which are produced as the result of aluminum corrosion in seawater. …
Date: April 5, 1978
Creator: Morse, J. W.; de Kanel, J. & Craig, Jr., H. L.
Object Type: Report
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.
Object Type: Article
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.
Object Type: Article
System: The UNT Digital Library
Detection and measurement of Post-Rosenbluth convective instability in MFTF with a hybrid CO/sub 2/ laser--heterodyne diagnostic system (open access)

Detection and measurement of Post-Rosenbluth convective instability in MFTF with a hybrid CO/sub 2/ laser--heterodyne diagnostic system

To measure and classify the Post-Rosenbluth convective loss-cone instability in MFTF, we propose to use a CO/sub 2/ laser consisting of a TEA-pulsed section and a low pressure CW section, together with a light mixing receiver. Calculations show that this system offers sufficient power and sensitivity to detect instability throughout the range from strong coherent light scattering to weak incoherent scattering when the instability is eliminated.
Date: October 5, 1977
Creator: Peratt, A.L.
Object Type: Report
System: The UNT Digital Library
Shawnee test program: TVA Shawnee Test Facility. Technical progress report, April 6-May 6, 1981 (open access)

Shawnee test program: TVA Shawnee Test Facility. Technical progress report, April 6-May 6, 1981

The test obtective for April was to evaluate sodium thiosulfate in limestone scrubber slurry as inhibitor of sulfite oxidation. The resulting effect on saturation levels of calcium sulfate (CaSO/sub 4/.2 H/sub 2/O; gypsum) and scaling in the system was of prime importance. As an antioxidant, S/sub 2/O/sub 3//sup =/ functions as a scale inhibitor by reducing SO/sub 4//sup =/, a known scale former. To meet the test objective, the scrubber was operated in a scaling mode as a base case; finally, the changes resulting from addition of sodium thiosulfate were evaluated. Train 100 was operated at two pH levels and with low and high sulfur coal in April. Because of several delays explained below, only base cases were completed in April.
Date: November 5, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
In-Home Performance of Exempt Pellet Stoves in Medford, Oregon. (open access)

In-Home Performance of Exempt Pellet Stoves in Medford, Oregon.

Pellet stoves that are considered exempt'' operate at an air-to-fuel ratio in excess of 35:1. They therefore qualify for exemption from the emissions certification process. A primary goal of this project was to determine how a sample of such stoves, operated in homes, would perform compared to their certified cousins,'' which were evaluated the previous year. In-home performance data documenting emissions from exempt stoves and net delivered efficiencies was particularly desired. This project evaluated six pellet stoves representing three major brands in Medford, Oregon. There were three Breckwell model P24FS, one Horizon Eclipse, one Horizon Destiny, and one Earth Stove TP40. The stoves were monitored for four week-long intervals in January and February 1991, for a total of 24 tests. Evaluations were conducted for particulate, CO (carbon monoxide) and PAH (polycyclic aromatic hydrocarbon) emissions and net efficiency. Monitoring was conducted using the AWES (automated woodstove emissions sampler) sampling system. A new data logger, developed for this project, was used to control the AWES and record real time data. 22 refs., 17 figs., 6 tabs.
Date: July 5, 1991
Creator: Barnett, Stockton G. & Fields, Paula G.
Object Type: Report
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.
Object Type: Article
System: The UNT Digital Library
Preliminary examination of the Linear Free-Electron Laser (open access)

Preliminary examination of the Linear Free-Electron Laser

The Linear Free Electron Laser is numerically analyzed in the one dimensional limit by following an average (resonant) particle. Several different wiggler schemes are presented, and electron beam current density requirements are discussed. A variable phase angle buncher is also proposed.
Date: February 5, 1979
Creator: Prosnitz, D. & Szoke, A.
Object Type: Report
System: The UNT Digital Library
Chief financial officer's task force on rationing feasibility, cost and schedule. Final report (open access)

Chief financial officer's task force on rationing feasibility, cost and schedule. Final report

The purpose of this memorandum is to report our realistic assessment of the feasibility, cost, and time frame for bringing a rationing program to 90-day readiness. The basic aspects of the nature of the rationing plan are discussed. The plan has been changed in several respects in response to comments from the Congress, the general public and the ECC, since the previous version was rejected by the Congress in May 1979. Three changes in particular impact the preimplementation process: The range of entities accorded status as priority firms has increased to cover such groups as telecommunications firms and for-hire delivery firms; All firms (not just priority users) are alloted rights for a percentage of their historical gasoline usage; States have more influence on the division of the total state supply between state reserves and vehicle allotments. The rationing plan, is described on a chart depicting the interaction of the principal components is included. The rationing process starts when checks for coupons are sent to owners of registered vehicles. The biggest single problem area appears to be delivering these checks into the hands of the vehicle registrants who are entitled to them. (DMC)
Date: March 5, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Improving the performance of brine wells at Gulf Coast strategic petroleum reserve sites (open access)

Improving the performance of brine wells at Gulf Coast strategic petroleum reserve sites

At the request of the Department of Energy, field techniques were developed to evaluate and improve the injection of brine into wells at Strategic Petroleum Reserve (SPR) sites. These wells are necessary for the disposal of saturated brine removed from salt domes where oil is being stored. The wells, which were accepting brine at 50 percent or less of their initial design rates, were impaired by saturated brine containing particulates that deposited on the sand face and in the geologic formation next to the wellbore. Corrosion of the brine-disposal pipelines and injection wells contributed to the impairment by adding significant amounts of particulates in the form of corrosion products. When tests were implemented at the SPR sites, it was found that the poor quality of injected brines was the primary cause of impaired injection; that granular-media filtration, when used with chemical pretreatment, is an effective method for removing particulates from hypersaline brine; that satisfactory injection-well performance can be attained with prefiltered brines; and that corrosion rates can be substantially reduced by oxygen-scavenging.
Date: November 5, 1979
Creator: Owen, L.B. & Quong, R. (eds.)
Object Type: Report
System: The UNT Digital Library
Investigation of photovoltaic mechanisms in polycrystalline thin-film solar cells. Interim technical report, November 1, 1980-July 31, 1981 (open access)

Investigation of photovoltaic mechanisms in polycrystalline thin-film solar cells. Interim technical report, November 1, 1980-July 31, 1981

Effort is reported on measurement technique development to assess the utility of Deep-Level Transient Spectroscopy (DLTS) methods in characterizing polycrystalline silicon that was deliberately doped with Ti during growth. Difficulties encountered with lateral DLTS measurements are discussed. In this approach, modulation of the grain boundary, double-depletion region produces the entire DLTS signal. Major effort has been applied in grain boundary characterization and control. The most significant accomplishments to date have involved laser scanning of slices of Wacker SILSO polysilicon having nearly identical grain structure. By using various kinds of treatments and by comparing treated and untreated substrates having nearly identical grain structure, control of grain boundary photocurrent suppression (..delta..I/sub ph/) over the range 1% less than or equal to ..delta..I/sub ph/ less than or equal to 40% was demonstrated.
Date: March 5, 1982
Creator: Temofonte, T. A.; Szedon, J. R. & O'Keeffe, T. W.
Object Type: Report
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.
Object Type: Article
System: The UNT Digital Library
Investigation of Clean Water Test Sites for Prototype Turbomachinery (open access)

Investigation of Clean Water Test Sites for Prototype Turbomachinery

Expanded development of total-flow expander technology in order to obtain efficient energy extraction from the liquid flow component of the geothermal well flow, in addition to steam enthalpy conversion, has been undertaken by the University of California, Lawrence Livermore Laboratory (LLL). The flow conditions necessary for this type of complete system performance characterization are beyond the capabilities of the test facility utilized in the preliminary tests at the LLL hot-water test facility. As an alternative to increasing the existing facility to meet the expanded test requirements, test facilities in the industrial California community are being surveyed to assess their capability in supporting future tests of the LLL expander. Biphase Engines, Inc. of Santa Monica, California was contracted by LLL to perform this survey. The goal of the Biphase Engines survey is to identify organizations with, first, an interest in supporting the LLL turbine test program and, second, to review their test capabilities with respect to the turbine test requirements. The results of the survey are described in the following sections which includes a listing of all organizations contacted. The responses to all inquiries are given. The affirmative responses to the test-support requirement are detailed with a description of the test …
Date: January 5, 1978
Creator: Cerini, Donald J.
Object Type: Report
System: The UNT Digital Library
ARM tropical pacific experiment (ATPEX): Role of cloud, water vapor and convection feedbacks in the coupled ocean/atmosphere system (open access)

ARM tropical pacific experiment (ATPEX): Role of cloud, water vapor and convection feedbacks in the coupled ocean/atmosphere system

We have initiated studies that include radiation model validation, improved treatment of the three-dimensional structure of cloud-radiation interactions, and sensitivity runs that will unravel the role of cloud-convection-radiation interactions in the Pacific Sear Surface Temperatures and the overlying Walker and Hadley circulation. The research program is divided into three phases: (1) radiation, (2) cloud parameterization issues; (3) feedback and ocean-atmosphere interactions.
Date: March 5, 1992
Creator: Ramanathan, V. & Barnett, T.P.
Object Type: Report
System: The UNT Digital Library