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

Description: 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.
Partner: UNT Libraries Government Documents Department
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Reliability of large superconducting magnets through design

Description: As superconducting magnet systems grow larger and become the central component of major systems involving fusion, magnetohydrodynamics, and high-energy physics, their reliability must be commensurate with the enormous capital investment in the projects. Although the magnet may represent only 15% of the cost of a large system such as the Mirror Fusion Test Facility, its failure would be catastrophic to the entire investment. Effective quality control during construction is one method of ensuring success. However, if the design is unforgiving, even an inordinate amount of effort expended on quality control may be inadequate. Creative design is the most effective way of ensuring magnet reliability and providing a reasonable limit on the amount of quality control needed. For example, by subjecting the last drawing operation is superconductor manufacture to a stress larger than the magnet design stress, a 100% proof test is achieved; cabled conductors offer mechanical redundancy, as do some methods of conductor joining; ground-plane insulation should be multilayered to prevent arcs, and interturn and interlayer insulation spaced to be compatible with the self-extinguishing of arcs during quench voltages; electrical leads should be thermally protected; and guard vacuum spaces can be incorporated to control helium leaks. Many reliable design options are known to magnet designers. These options need to be documented and organized to produce a design guide. Eventually, standard procedures, safety factors, and design codes can lead to reliability in magnets comparable to that obtained in pressure vessels and other structures. Wihout such reliability, large-scale applications in major systems employing magnetic fusion energy, magnetohydrodynamics, or high-energy physics would present unacceptable economic risks.
Date: September 5, 1980
Creator: Henning, C.D.
Partner: UNT Libraries Government Documents Department
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Application of microfabrication technology to thermionic energy conversion. Progress report 4, 1 May 1980 to 31 July 1980

Description: 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.
Partner: UNT Libraries Government Documents Department
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A Search for New Leptons with Heavy Neutrinos in e/sup +/e/sup -/ Annihilation at. sqrt. s = 29 GeV. [None]

Description: 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.
Partner: UNT Libraries Government Documents Department
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Physical characterization of magmatic liquids. [Ultrasonic and Brillouin Scattering Studies of Natural and Synthetic Silicates and Oxides]

Description: 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.
Partner: UNT Libraries Government Documents Department
open access

Development and testing of shingle-type solar cell modules. Quarterly report No. 2

Description: The details of a shingle module design which produces in excess of 97 watts/m/sup 2/ of module area at 1 kW/m/sup 2/ insolation and at 60/sup 0/C are reported. This selected design employs a tempered glass coverplate to provide the primary solar cell structural support. The use of the B.F. Goodrich FLEXSEAL roofing system as the outer skin of the shingle substrate provides a high confidence of achieving the 15 year service life goal. The fabrication and testing of a preproduction module of this design has demonstrated that this selected approach will meet the environmental testing requirements imposed by the contract. Attempts to fabricate a preproduction module of an alternative design, which embeds the solar cell assembly within a methyl methacrylate casting, proved unsuccessful.
Date: January 5, 1978
Creator: Shepard, N.F.
Partner: UNT Libraries Government Documents Department

[Students in Homecoming Parade]

Description: Photograph of UNT students in the back of trucks during the Homecoming Parade. The truck in front is decorated with a soccer ball, basketball and softball and is pulling a trailer with students wearing hard hats. The truck behind them has a UNT flag on its hood. Students are also walking beside the vehicles.
Date: November 5, 2016
Creator: Clark, Junebug
Partner: UNT Libraries Special Collections
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