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Design studies of a laser fusion power plant (open access)

Design studies of a laser fusion power plant

The conceptual design of a laser fusion power plant has been undertaken to exploit recent developments in target design. Advanced high-gain targets which have been developed make it possible to significantly relax the laser and optical system requirements. The power plant design features a reactor concept which utilizes a thick falling region of liquid lithium to protect the first-wall from the neutrons, x-rays, and charged particles that are produced in the thermonuclear microexplosion. The lithium waterfall has also been designed to be thick enough to significantly reduce the effects of 14 MeV neutrons and cyclical stresses on the blanket structure; thereby allowing us to consider smaller blanket structures which could last the lifetime of the plant. Fusion targets producing 700 MJ of thermonuclear energy are ignited by a 2 percent efficient, 1 MJ laser system at the rate of 1.4 Hz. Schemes for protecting the final focusing optics are described which are both compatible with this reactor system, and show promise of surviving a full year in order to minimize costly downtime.
Date: October 7, 1977
Creator: Maniscalco, J. A.; Meier, W. R. & Monsler, M. J.
System: The UNT Digital Library
Analysis of three-phase power-supply systems using computer-aided design programs (open access)

Analysis of three-phase power-supply systems using computer-aided design programs

A major concern of every designer of large, three-phase power-supply systems is the protection of system components from overvoltage transients. At present, three computer-aided circuit design programs are available in the Magnetic Fusion Energy (MFE) National Computer Center that can be used to analyze three-phase power systems: MINI SCEPTRE, SPICE I, and SPICE II. These programs have been used at Lawrence Livermore Laboratory (LLL) to analyze the operation of a 200-kV dc, 20-A acceleration power supply for the High Voltage Test Stand. Various overvoltage conditions are simulated and the effectiveness of system protective devices is observed. The simulated overvoltage conditions include such things as circuit breaker openings, pulsed loading, and commutation voltage surges in the rectifiers. These examples are used to illustrate the use of the computer-aided, circuit-design programs discussed in this paper.
Date: October 7, 1977
Creator: Oberst, E.F.
System: The UNT Digital Library
Reel support for wind the magnet of the Mirror Fusion Test Facility (open access)

Reel support for wind the magnet of the Mirror Fusion Test Facility

The reel support has three main functions. It must support the reel, which is 134 in. in diameter, 40 in. wide, and stores up to 8,600 ft of superconductor weighing 8,600 lb. It also must serve as a tensioning device for the superconductor, exerting a force of up to 600 lb. Further, the support must move the reel vertically and laterally to facilitate the winding of the magnets. The support has been designed and is now being fabricated. This paper describes the performance requirements of this device and the evolution of design from concept to completion.
Date: September 7, 1977
Creator: Ling, R.C.; Chang, Y. & Hunt, L.D.
System: The UNT Digital Library
Testing of developmental neutral beam sources for MFTF (open access)

Testing of developmental neutral beam sources for MFTF

The design of a four-grid, spherically-focused, 10-by-46-cm area accelerator and ion source for the Mirror Fusion Test Facility (MFTF) has been previously described. This source was designed to operate at 80 kV-80 A for 0.5 s, and along with a matching, three-grid 20-kV-100-A-10-ms accelerator, has been built and tested. The 80-kV source has operated beyond design specifications to 90 kV-90 A for 12 ms. Pulse duration was limited by a capacitor bank accelerator power supply. Tests to 0.5 s on the High Voltage Test Stand (HVTS) are in progress. The major change found necessary during testing was the installation of a grounded shield to block neutralizer plasma from flowing into the region between high voltage and ground. The D/sub 1//sup +/:D/sub 2//sup +/:D/sub 3//sup +/ ratio was measured by Doppler shift spectroscopy and momentum analysis to be 0.68:0.20:0.12. Accelerator grids are built to a 7-m-radius spherical surface that aims individual beamlets at the center of curvature.
Date: November 7, 1979
Creator: Molvik, A.W.
System: The UNT Digital Library
The Equilibrium Length of High-Current Bunches in Electron Storage Rings (open access)

The Equilibrium Length of High-Current Bunches in Electron Storage Rings

An equilibrium theory of the length of intense electron bunches circulating in a storage ring is presented. The consequence of electrical interaction with various resonant structures is expressed in terms of quadratures over the impedance of the structures, and impedance functions for a variety of elements are evaluated. It is shown that elements having resonances at high frequency can, above transition, cause bunches to increase in length with increasing current. The parametric dependence of the bunch lengthening is found to be in good agreement with observations, and numerical estimates, which are in substantial agreement with experiment, are presented.
Date: August 7, 1970
Creator: Pellegrini, C. & Sessler, A. M.
System: The UNT Digital Library
Silica control and materials tests at the Salton Sea geothermal field (open access)

Silica control and materials tests at the Salton Sea geothermal field

The Lawrence Livermore Laboratory maintains and operates a test facility near Niland, California, in the Imperial Valley for field studies on SSGF brine chemistry, scale and solids control, materials, and injection. Recent work in silica control and materials testing is reviewed.
Date: June 7, 1979
Creator: Quong, R.; Harrar, J. E.; McCright, R. D.; Locke, R. D.; Lorensen, L. E. & Tardiff, G. E.
System: The UNT Digital Library
Differencing asymptotic diffusion theory (open access)

Differencing asymptotic diffusion theory

A diffusion theory is presented which extends asymptotic diffusion to non-uniform material properties. Finite difference methods for the diffusion theory naturally result in jump conditions on interfaces when appropriate.
Date: June 7, 1979
Creator: Zimmerman, G.B.
System: The UNT Digital Library
Optical design of the TMX Thomson Scattering Diagnostic (open access)

Optical design of the TMX Thomson Scattering Diagnostic

The Thomson Scattering Diagnostic on TMX was built to measure the electron temperature in the plug. The design was based on the 2XII system built by Tom Simonen. Substantial improvements were realized over the original design, these include: (1) improved sensitivity, (2) simultaneous multiple position sampling, (3) multiple pulse capability, (4) achromatic imaging, (5) vacuum alignment capability, (6) high reliability, and (7) built in calibration and performance monitoring.
Date: November 7, 1979
Creator: Frank, A.M.
System: The UNT Digital Library
Start-up neutral-beam power supply system for MFTF (open access)

Start-up neutral-beam power supply system for MFTF

This paper describes some of the design features and considerations of the MFTF start-up neutral-beam power supplies. In particular, we emphasize features of the system that will ensure MFTF compatibility and achieve the required reliability/availability for the MFTF to be successful.
Date: November 7, 1979
Creator: Mooney, L. J.
System: The UNT Digital Library
Solving the geologic issues in nuclear waste disposal (open access)

Solving the geologic issues in nuclear waste disposal

Technical problems with nuclear waste disposal are largely geological. If these are not solved, curtailment of nuclear power development may follow, resulting in loss of an important element in the national energy supply. Present knowledge and credible advances are capable of solving these problems provided a systems view is preserved and a national development plan is followed. This requires identification of the critical controllable elements and a systematic underground test program to prove those critical elements. Waste migration can be understood and controlled by considering the key elements in the system: the system geometry, the hydrology, and the waste-rock-water chemistry. The waste program should: (1) identify and attack the critical problems first; (2) provide tests and demonstration at real disposal sites; and (3) schedule elements with long lead-times for early start and timely completion.
Date: September 7, 1979
Creator: Towse, D.
System: The UNT Digital Library
Progress on Lawrence Livermore Laboratory's superconducting High-Field Test Facility (open access)

Progress on Lawrence Livermore Laboratory's superconducting High-Field Test Facility

A split pair of multifilamentary Nb/sub 3/Sn conductor coils, inside a set of Nb-Ti background coils, is being built at Lawrence Livermore Laboratory (LLL) for use in the High-Field Test Facility (HFTF). The inside diameter of the Nb/sub 3/Sn winding is 40 cm, the peak field is 12 T, and the nominal conductor current is 5 kA. The coils are being built as part of the LLL high-field superconducting development program in which characterization of short samples is followed by demonstration in coils incorporating production lengths of conductor. The HFTF will also be used to study the characteristics of prototype conductors designed to meet the requirements of tokamak toroidal field coils having a maximum field of 12 T. These conductors will be tested one at a time, inserted in the form of small coils in the split between the Nb/sub 3/Sn coils in the HFTF. The paper describes the coil system and gives a summary of the present state of its development and fabrication.
Date: November 7, 1979
Creator: Cornish, D. N.; Harrison, H. L.; Jewell, A. M.; Leber, R. L.; Rosdahl, A. R.; Scanlan, R. M. et al.
System: The UNT Digital Library
Shock initiation of explosive pellets at low temperature. [PETN, PBX-9407, HNS-1] (open access)

Shock initiation of explosive pellets at low temperature. [PETN, PBX-9407, HNS-1]

Electrically-driven flyer plates have been used to initiate the high explosives PETN, PBX-9407 and HNS-1 at 194/sup 0/K and 77/sup 0/K. Electrically-exploded aluminum foils accelerated 51-..mu..m thick plastic flyer plates to impact the explosive pellets. The flyer-plate components and the explosive pellets were cooled to the desired temperature by immersing them in dry ice (194/sup 0/K) or liquid nitrogen (77/sup 0/K). Two firing systems were used. In one system a 0.6..mu..F capacitor supplies energy to a 0.635 x 0.011mm bridgefoil. In the other system a 6.0..mu..F capacitor supplies energy to a 1 x 1 x 0.011mm bridgefoil. The change in threshold current for initiation due to temperature effects is discussed.
Date: February 7, 1979
Creator: Gilman, D.S.
System: The UNT Digital Library
Flash x-ray. [Nondestructive testing of material that is moving or changing very rapidly] (open access)

Flash x-ray. [Nondestructive testing of material that is moving or changing very rapidly]

The complementary techniques of flash x-ray radiography (FXR) and flash x-ray diffraction (FXD) provide access to a unique domain in nondestructive materials testing. FXR is useful in studies of macroscopic properties during extremely short time intervals, and FXD, the newer technique, is used in studies of microscopic properties. Although these techniques are similar in many respects, there are some substantial differences. FXD generally requires low-voltage, line-radiation sources and extremely accurate timing; FXR is usually less demanding. Phenomena which can be profitably studied by FXR often can also be studied by FXD to permit a complete materials characterization.
Date: September 7, 1976
Creator: Johnson, Q. & Pellinen, D.
System: The UNT Digital Library
Computing unit: a measure of total computer utilization (open access)

Computing unit: a measure of total computer utilization

The basis on which charges are calculated for use of computers at LBL is explained. CPU time, I/O requirements, and memory utilized are among the primary factors considered. (RWR)
Date: December 7, 1976
Creator: Stevens, D. F. & White, H. S.
System: The UNT Digital Library
Effects of cyclotron radiation in magnetically-confined p-/sup 11/B reactors (open access)

Effects of cyclotron radiation in magnetically-confined p-/sup 11/B reactors

Confinement parameters, ntau, are calculated for several possible magnetically-confined p-/sup 11/B reactor configurations using a computer code that evaluates cyclotron radiation emission by electrons and follows the energy distributions of the reactants and products explicitly as they undergo nuclear reactions and both low and high angle scattering. The present treatment of cyclotron radiation assumes a uniform magnetic field and an isotropic plasma. Reflectivity is included as an input parameter. The influence of cyclotron radiation on the energy balance of the various p-/sup 11/B reactor configurations is evaluated and the deviation of the electron distribution from a Maxwellian due to cyclotron radiation emission is studied.
Date: November 7, 1975
Creator: Chu, T. C.
System: The UNT Digital Library
Assessment of very high temperature reactors in process applications (open access)

Assessment of very high temperature reactors in process applications

In April 1974, the United States Energy Research and Development Administration (ERDA) authorized General Atomic Company, General Electric Company, and Westinghouse Astronuclear Laboratory to assess the available technology for producing process heat utilizing a very high temperature nuclear reactor (VHTR). The VHTR is defined as a gas-cooled graphite-moderated reactor. Oak Ridge National Laboratory has been given a lead role in evaluating the VHTR reactor studies and potential applications of the VHTR. Process temperatures up to the 760 to 871/sup 0/C range appear to be achievable with near-term technology. The major development considerations are high temperature materials, the safety questions (especially regarding the need for an intermediate heat exchanger) and the process heat exchanger. The potential advantages of the VHTR over competing fossil energy sources are conservation of fossil fuels and reduced atmospheric impacts. Costs are developed for nuclear process heat supplied from a 3000-MW(th) VHTR. The range of cost in process applications is competitive with current fossil fuel alternatives.
Date: April 7, 1976
Creator: Jones, J. E. Jr.; Spiewak, I. & Gambill, W. R.
System: The UNT Digital Library
MHSS: a material handling system simulator (open access)

MHSS: a material handling system simulator

A Material Handling System Simulator (MHSS) program is described that provides specialized functional blocks for modeling and simulation of nuclear material handling systems. Models of nuclear fuel fabrication plants may be built using functional blocks that simulate material receiving, storage, transport, inventory, processing, and shipping operations as well as the control and reporting tasks of operators or on-line computers. Blocks are also provided that allow the user to observe and gather statistical information on the dynamic behavior of simulated plants over single or replicated runs. Although it is currently being developed for the nuclear materials handling application, MHSS can be adapted to other industries in which material accountability is important. In this paper, emphasis is on the simulation methodology of the MHSS program with application to the nuclear material safeguards problem. (auth)
Date: April 7, 1976
Creator: Pomernacki, L. & Hollstien, R. B.
System: The UNT Digital Library
Collective behavior in recent laser-plasma experiments (open access)

Collective behavior in recent laser-plasma experiments

The absorption of 1.06 ..mu.. light focused on small C/sub 8/H/sub 8/ discs has been measured in the intensity range of 10/sup 15/ - 10/sup 17/ W/cm. The data confirms the importance of collective plasma effects in determining the absorption of intense light. The measured absorption efficiencies are in the range of 30 to 40 percent, and the scattered light has a polarization dependence. The measured absorptions are shown to be inconsistent with classical inverse bremsstrahlung. Both the magnitude of the absorption and the observed polarization dependence of the scattered light are shown to be consistent with recent calculations of light absorption via collective processes. Comparisons are made, and improved models of the light absorption are discussed with reference to the data. In addition, the heated electron energies deduced from the x-ray data are consistent with those expected via collective processes.
Date: June 7, 1976
Creator: Kruer, W. L.; Haas, R. A.; Mead, W. C.; Phillion, D. W. & Rupert, V. C.
System: The UNT Digital Library
Assessment of a chemical getter for scavenging tritium from an inert gas (open access)

Assessment of a chemical getter for scavenging tritium from an inert gas

Results are presented of a study aimed at determining the feasibility of using chemical getter beds to scavenge tritium from inert gases. Two types of getter bed, fixed and fluidized, were considered, using cerium as the getter material. Mathematical-modeling results and capital-cost estimates indicate that not only is the gettering approach technically feasible, it could lead to considerable cost savings over catalytic oxidation, the tritium-removal method traditionally used.
Date: May 7, 1976
Creator: Maienschein, J. L.
System: The UNT Digital Library
Summary review of rock mechanics workshop on radioactive waste disposal (open access)

Summary review of rock mechanics workshop on radioactive waste disposal

Presentations, critiques and recommendations for the disposal of commercial radioactive waste based upon an analysis of the information presented at the Rock Mechanics Review/Workshop, Denver, Colorado, December 16-17, 1976 are summarized. The workshop, comprised of both formal and informal sessions, with about 50 participants, was hosted by RE/SPEC Inc. and Dr. Paul F. Gnirk, President and was sponsored by the Office of Waste Isolation (OWI), led by Dr. William C. McClain. The panel of reviewers, responsible for this report, consisted of Neville L. Carter, Richard E. Goodman, and Robert H. Merrill. These panel members were selected not only on the basis of their experience in various aspects of Rock Mechanics and Mining Engineering but also because they have had no previous active participation in problems concerning disposal of radioactive waste. By way of a general comment, the review panel was very favorably impressed with the Rock Mechanics research efforts, supported by OWI, on this problem and with the level of technical competence of those carrying out the research. Despite the rather preliminary nature of the results presented and the youth of the program itself, it is clear that the essential ingredients for a successful program are at hand, especially as …
Date: February 7, 1977
Creator: Carter, N. L.; Goodman, R. E. & Merrill, R. H.
System: The UNT Digital Library
Vacuum engineering for fusion research and fusion reactors (open access)

Vacuum engineering for fusion research and fusion reactors

The following topics are described: (1) surface pumping by cryogenic condensation, (2) operation of large condensing cryopumps, (3) pumping for large fusion experiments, and (4) vacuum technology for fusion reactors. (MOW)
Date: September 7, 1976
Creator: Pittenger, L. C.
System: The UNT Digital Library
Human semen assays for workplace monitoring. [Monitoring of hazardous materials by determining effects on semen of personnel] (open access)

Human semen assays for workplace monitoring. [Monitoring of hazardous materials by determining effects on semen of personnel]

Decades of human semen studies have yielded compelling evidence that sperm can be used to access reproductive potential and diagnose pathology. With these studies as background, the small number of detailed semen studies of men exposed to physical and chemical agents point with optimism to the application of human semen assays as efficient, effective means to monitor for reproductive hazards in the workplace. Sperm are the most accessible of human gonadal tissue and provide a means of monitoring exposure induced changes in the human testes, changes which may result in infertility and increased frequencies of genetically abnormal gametes. The focus on semen has precipitated the development of new sperm bioassays which use older conventional andrological methods (i.e., sperm counts, motility, and morphology) as well as recently developed high speed flow and scanning methods for automated cytological analyses. The status of these sperm assays for workplace surveillance is reviewed, procedures are suggested with examples of use, and their effectiveness is evaluated. The available mouse models of induced semen changes are briefly described and the importance of these models for evaluating the genetic implications of findings in human semen is discussed.
Date: November 7, 1978
Creator: Wyrobek, A.J. & Gledhill, B.L.
System: The UNT Digital Library
Time-dependent FEM solution of the incompressible Navier--Stokes equations in two- and three-dimensions (open access)

Time-dependent FEM solution of the incompressible Navier--Stokes equations in two- and three-dimensions

Future prospects regarding the numerical solution of the Navier-Stokes equations using the finite element method are discussed. Since the ultimate goal is to solve these equations in three-dimensions, only the primitive variable (u,P) formulation is considered. A novel feature of the two-dimensional solution technique relates to the methodology developed and employed for solving the semi-discretized system of ordinary differential equations, which are outlined in the section describing the development of the two-dimensional code. Following the discussion of numerical results from two-dimensional calculations, three-dimensional flows are discussed, where several potentially viable options are considered. (TFD)
Date: July 7, 1978
Creator: Gresho, P.M.; Lee, R.L.; Sani, R.L. & Stullich, T.W.
System: The UNT Digital Library
Effects of various polishing media and techniques on the surface finish and behavior of laser glasses (open access)

Effects of various polishing media and techniques on the surface finish and behavior of laser glasses

The advance of high-power laser technology is dependent on the rate of advancement in laser glass forming and surface preparation. The threshold damage of glass surfaces continues to be a weak link in the overall advancement of laser technology. Methods were developed and used in the evaluation of existing glass surface preparation techniques. Modified procedures were evaluated to reduce surface contamination and subsurface defects. Polishing rates were monitored under controlled polishing conditions (purity, pH, particle size distribution, particle concentration, etc.). Future work at LLL for this ongoing investigation is described.
Date: November 7, 1978
Creator: Landingham, R. L.; Casey, A. W. & Lindahl, R. O.
System: The UNT Digital Library