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A fiber optic synchronous detector using sample-and-hold circuits

Pfeifer, Kent B.

A design for a synchronous driver and detector for single-ended optical fiber sensing applications is presented. The circuit is discussed in detail. A derivation of the equations relating the input to the output for the sampler is given. A brief discussion of the operation of the prototype is given. Finally, the paper concludes with an example of an application of the device. 8 refs., 7 figs.

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Weldability and weld doping of commercial purity molybdenum

Robino, Charles V.

The GTA weldability and fracture behavior of low and high carbon arc cast and powder metallurgy molybdenum has been examined. Defect-free welds were produced in the arc cast grades. For the PM grade, however, severe centerline cracking and large scale porosity were encountered. The center-line cracking and pore formation were found to result from the dissolution of oxygen-bearing inclusions present in the starting material. Moreover, titanium or hafnium additions, incorporated into the weld by RF sputter coating the joints prior to welding, had several beneficial effects. These were reductions in the centerline cracking and pore formation in the PM welds, hardening of the weld fusion zone, and a reduction in the tendency for intergranular failure in the fusion zone for all base materials. The mechanisms by which dopant additions improve the welding and fracture behavior is also discussed. 22 refs., 16 figs., 2 tabs.

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TORE SUPRA graphite inner first wall

Chappuis, P.; Aymar, R.; Deschamps, P.; Gabriel, M.; Croessman, C.

TORE SUPRA is a fairly large tokamak and has an original goal to withstand a large power removal (25 MW) during a 30 seconds long pulse. One of the main energy removal system's is the inner first wall which was originally designed for the following aims: protect the inner side of the vacuum vessel from normal plasma operation (participates to the plasma power removal) and against disruptive events (plasma energy quench and current decay); act as a toroidal belt limiter during steady state operation and plasma start up; and protect the vacuum vessel from the shine through of the neutral beam injectors and act as a beam dump for short shots. In order to match those different goals the design choice was oriented towards an actively cooled graphite wall capable to sustain an 1 MW/m/sup 2/ continuous heat flux. This paper discusses this design concept further.

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A calorimetric-based comparison of gas tungsten and plasma arc welding processes

Knorovsky, Gerald A.

Measurements of arc and melting efficiencies have been made for pulsed and continuous mode Gas Tungsten Arc Welding (GTAW) and Plasma Arc Welding (PAW) processes. Welds were made on 2.5 mm total thickness pure Ni and 304 Stainless Steel in a standing edge weld geometry at constant nominal machine output settings which varied average current with travel speed. Under continuous current conditions, the measured heat input remained approximately constant for the conditions examined (250-1250 mm/min), while melting efficiency increased dramatically (0-/approximately/0.4). Arc efficiencies were relatively constant, remaining in the range of /approximately/0.75-0.85 for GTAW and somewhat less for PAW. Values of melting efficiency for Ni were slightly less than those for 304 when compared at similar travel speeds, though both tended toward the same limit (/approximately/0.4). The PAW results were not appreciably higher than the GTAW. In addition to melting efficiency the centerline depth of penetration was also measured. In contrast to the GTAW results, which increased with speed at lower travel speeds and then plateaued at 0.8 mm, the PAW results increased monotonically with speed to a maximum of 1.0 mm. In conclusion, calorimetric measurements of nonconsumable arc welding processes have been found helpful in understanding conditions under which efficient arc welds with minimal heat inputs for a desired weld penetration can be made. 10 figs.

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Performance of the RHIC-II clean room facility at Sandia National Laboratories

Brown, N.E.; Van Geet, O.D.; Liu, B.Y.H.; O; Hanlon, J.F.

The clean rooms in the new Radiation Hardened Integrated Circuit (RHIC-II) Facility have become operational. Design philosophy and information on the air handling system, initial data on particulate contamination levels in clean bays, service chases and the make up air system will be presented. Data on power consumption, particulate levels before and after the HEPA filters and sound levels with air velocities from 95 to 57 feet per minute will be reported. 2 refs., 5 figs., 4 tabs.

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Heat removal considerations in a tokamak pump limiter design

Koski, Jorman A.

In experimental fusion energy devices such as tokamaks, pump limiters are used to define the plasma edge as well as control the plasma density and impurity. Since these devices must operate at the edge of the plasma, they are subject to high heat flux incidence from the plasma side. In this paper, one of the active heat removal schemes considered for the outboard pump limiter of Tore Supra, a tokamak under construction in Cadarache, France, is analyzed in some detail. The scheme involves cooling by forced convective nucleate boiling of water at the limiter leading edges and by forced convection of high pressure helium at its front face. 14 refs., 5 figs., 4 tabs.

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Magnetic Fusion Energy Program

Gauster, Wilhelm B.

This report discusses the projects and device support for the following thermonuclear reactors: Tokamak Fusion Test Reactor, Compact Ignition Tokamak, International Thermonuclear Experimental Reactor, Joint European Torus, Textor, Tore-Supra, DIII-D, and ASDEX and ASDEX Upgrade. This paper also discusses High-Heat Flux Materials and Components and Plasma Surface Interactions Research.

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NUMERICAL MODELING OF THE DRYING OF POROUS MATERIALS

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Hadley, G.R.

A numerical solution technique has been presented which solves in one dimension the coupled heat and mass flow equations for water, water vapor, and an inert gas moving through a porous medium. The physical effects included in the resulting computer program PETROS are more complete than for previous simulations, particularly for the gas phase transport. The latter includes effects due to binary gaseous diffusion and Knudsen diffusion as well as Darcy flow. PETROS is thus capable of simulating two-phase flow through porous media.

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Updated Drucker-Prager Constants for Anhydrite and Polyhalite

Morgan, H.S.; Krieg, R.D.

The Waste Isolation Pilot (WIPP) reference stratigraphy contains layers of both anhydrite and polyhalite which mush be included in models used to compute the response of WIPP rooms and drifts. These layers have usually been modeled as elastic materials due to the ease in implementing elastic models.

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The solar thermal report. Volume 3, Number 5

O'Canna, Myra L.

This report is published by the Jet Propulsion Laboratory for the DOE Solar Thermal Technology Division to provide an account of work sponsored by the Division and to aid the community of people interested in solar thermal technology in gaining access to technical information. Contents include articles entitled the following: Solar system supplies thermal energy for producing chemicals at USS plant; Solar thermal power module designed for small community market; Roof-mounted trough system supplies process heat for Caterpillar plant; Solar thermal update -- 10 MW(e) pilot plant and 3-MW(t) total energy system; Solar steam processes crude oil; New York investigates solar ponds as a source of thermal energy; On-farm solar -- Finding new uses for the sun; and Topical index of solar thermal report articles.

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Proposal to study stem forgings

O'Canna, Myra L.

Reservoir designs consist of two primary features including the stem(s) and the body segment. The stem is either an integral part of the reservoir or is joined at some point in the fabrication sequence. The current interest is in high strength stems for advanced reservoir designs. The processing necessary to achieve these strength levels may result in heavily cold worked microstructures which may not interface well with the stem requirements. For instance, cold worked 316 plate stock has shown decreased hydrogen compatibility when contrasted to the annealed version in laboratory tests. More recently, Precision Forge produced a 100 ksi yield strength, 304L stem forging with a heavily deformed microstructure which also may show decreased compatibility in hydrogen. The proposed forging contract will evaluate the influence of forging parameters on the microstructure and mechanical properties of 304L and 316 stem forgings. A summary of the data available on 304L stem forgings is shown graphically. The yield strength values are shown for each set of forging parameters. Tensile tests and microstructural examination will be conducted to complete the information for 304L and create a similar graph for 316 stem forgings.

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Solar energy at Sandia National Laboratories

O'Canna, Myra L.

Basic concepts for using the energy of the sun have been known for centuries. The challenge today, the goal of the Department of Energy`s National Solar Energy Program is to create the technology needed to establish solar energy as a practical, economical alternative to energy produced by depletable fuels--and to use that solar-produced energy in a wide variety of applications. To assist the DOE in this national effort, Sandia sponsors industrial and university research and development, manages a series of technical programs, operates solar experimental facilities, and carries out its own scientific and engineering research. This booklet describes their projects, their technical objectives, and explains how their experimental facilities are used to find the answers we`re seeking. Prospective participants from companies involved in solar-energy development or applications should find it especially useful since it outlines broad areas of opportunity. Projects include: central receiver technology; line-focus thermal technology; photovoltaic systems technology; wind turbine development; energy storage technology; and applied research in improved polycrystalline materials for solar cells and photoelectrolysis of water.

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MISR -- Solar and steam for industry

O'Canna, Myra L.

The goal of the MISR project is to assist industry in developing viable Solar Energy Systems which have high reliability and low cost because they do not require custom engineering and installation for each industrial site. The collector field, piping and steam generation equipment are pre-engineered to be suitable for a wide range of industrial steam applications. The approach of the MISR project is twofold: to develop line-focus industrial solar thermal energy systems which, like conventional packaged steam boilers, are based on the modular concept; and to install and operate a number (10 or less) of these systems at existing industrial plants, supplementing steam produced by conventional boilers. The project is briefly described.

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Modular Industrial Solar Retrofit fact sheet

O'Canna, Myra L.

The MISR project has two goals. One is to assist industry in developing viable Solar Energy Systems which have high reliability and low cost because they do not require tailored engineering and installation for each industrial site. The collector field, piping and steam generation equipment are pre-engineered to be suitable for a wide range of industrial steam applications. This is the Modular Concept. The second goal is to fabricate, install, and test qualification test systems (representative of full-size MISR designs in all but the size of the collector field) to determine design quality, fabrication and installation correctness, and system cost. This activity allows the designers to produce the first MISR system, experimentally verify its operation and performance before committing to large scale solar installations, thereby avoiding the risks associated with the first system. It provides the potential industrial user with information upon which to base solar energy decisions. Five separate system designs are being developed under the MISR project. Four of the designs are being tested at Sandia National Laboratories at Albuquerque, New Mexico and one is being tested at the Solar energy Research Institute in Golden, Colorado.

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The evaluation of Ontario Forge Company as a qualified forging vendor

O'Canna, Myra L.

There has been a long standing need to develop a second source of WR quality forgings for the manufacturing of J-line hardware at RF. With this objective, Ontario Forge Company was recently evaluated to determine if their equipment and skills were compatible with the forging requirements. The results of this evaluation were compared to test results on WR forgings of a similar design produced by Precision Forge Company. The Ontario Forge Company forgings exhibited mechanical properties, grain flow and microstructures equivalent to those of Precision Forge Company. The Ontario Forge Company performance on this contract justifies the qualification of their process for producing non-critical reservoir forgings. Qualifying Ontario Forge Company for critical reservoir forgings is recommended only after sufficient production experience and storage data is acquired.

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GeoEnergy technology

O'Canna, Myra L.

The goal of the GeoEnergy Technology Program is to improve the understanding and efficiency of energy extraction and conversion from geologic resources, hence maintaining domestic production capability of fossil energy resources and expanding the usage of geothermal energy. The GeoEnergy Technology Program conducts projects for the Department of Energy in four resource areas--coal, oil and gas, synthetic fuels and geothermal energy. These projects, which are conducted collaboratively with private industry and DOE`s Energy Technology Centers, draw heavily on expertise derived from the nuclear weapons engineering capabilities of Sandia. The primary technologies utilized in the program are instrumentation development and application, geotechnical engineering, drilling and well completions, and chemical and physical process research. Studies in all four resource areas are described.

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Particle beam fusion

O'Canna, Myra L.

Today, in keeping with Sandia Laboratories` designation by the Department of Energy as the lead laboratory for the pulsed power approach to fusion, its efforts include major research activities and the construction of new facilities at its Albuquerque site. Additionally, in its capacity as lead laboratory, Sandia coordinates DOE-supported pulsed power fusion work at other government operated laboratories, with industrial contractors, and universities. The beginning of Sandia`s involvement in developing fusion power was an outgrowth of its contributions to the nation`s nuclear weapon program. The Laboratories` work in the early 1960`s emphasized the use of pulsed radiation environments to test the resistance of US nuclear weapons to enemy nuclear bursts. A careful study of options for fusion power indicated that Sandia`s expertise in the pulsed power field could provide a powerful match to ignite fusion fuel. Although creating test environments is an achieved goal of Sandia`s overall program, this work and other military tasks protected by appropriate security regulations will continue, making full use of the same pulsed power technology and accelerators as the fusion-for-energy program. Major goals of Sandia`s fusion program including the following: (1) complete a particle accelerator to deliver sufficient beam energy for igniting fusion targets; (2) obtain net energy gain, this goal would provide fusion energy output in excess of energy stored in the accelerator; (3) develop a technology base for the repetitive ignition of pellets in a power reactor. After accomplishing these goals, the technology will be introduced to the nation`s commercial sector.

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TIGER -- A technology to improve the delivery capability of nuclear bombs and the survivability of the delivery aircraft

O'Canna, Myra L.

The TIGER (Terminal guided and Extended-Range) Program was initiated in 1972 to study improved delivery capabilities for stockpiled tactical nuclear bombs. The Southeast Asia conflict fostered the development of air-delivered standoff conventional weapons utilizing terminal guidance systems. SNL initiated the TIGER program to determine if current nuclear bombs could be provided with a similarly accurate standoff capabilities. These conventional weapon delivery techniques, while allowing highly accurate attack, generally require entering the target area at high altitude to establish line of sight to the target. In parallel with the TIGER program, system studies analyzed this concept and showed marked improvement in aircraft and weapon survivability with moderate standoff (10--20 km) if low level deliveries (60 m) could be accomplished. As a result of this work, the TIGER program was redirected in early 1974 to demonstrate a standoff bomb with good accuracy (90 m CEP) when delivered from low flying aircraft. This program redirection resulted in the selection of an inertial guidance system to replace the earlier terminal guidance systems. This program was called the Extended-Range Bomb (ERB). In May 1974, a joint Air Force/DOE study identified the desirability of having a single tactical weapon which could be employed against either fixed, preselected targets, or mobile battlefield targets. Studies conducted on the ERB system showed that the inertially guided weapon could fly not only the standoff mission but also a return-to-target mission against the mobile battlefield targets whose locations are not known accurately enough to use a standoff delivery. The ERB program evolved from these initial investigations into an exploratory program to develop the hardware and demonstrate the technology required to fly standoff and return-to-target trajectories. The application of this technology in the form of field retrofit kits to the B61 bomb is called TIGER II.

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Particle-beam fusion research facilities at Sandia National Laboratories

O'Canna, Myra L.

Sandia research in inertial-confinement fusion (ICF) is based on pulse-power capabilities that grew out of earlier developments of intense relativistic electron-beam (e-beam) radiation sources for weapon effects studies. ICF involves irradiating a deuterium-tritium pellet with either laser light or particle beams until the center of the pellet is compressed and heated to the point of nuclear fusion. This publication focuses on the use of particle beams to achieve fusion, and on the various facilities that are used in support of the particle-beam fusion (PBF) program.

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Solar thermal repowering

O'Canna, Myra L.

Solar central receiver technology is developing steadily with a promise of becoming a real commercial alternative for energy generation in the late 1980s. Significant potential markets have been identified, research and development of important components is proceeding well, and the first full-system verification experiment at Barstow, California, is under construction. However, much work still lies ahead. A big step toward the realization of large-scale commercial use of solar energy was taken when the Department of Energy (DOE) issued a solicitation in March 1979 for utility repowering/industrial retrofit system conceptual design studies employing solar central receivers. Twenty-two responses were evaluated, and twelve were selected for funding. The results of the twelve studies, plus one study completed earlier and one privately funded, are sufficiently encouraging to warrant proceeding to the next stage of the program: cost-shared projects chosen through open competition. Eight of he fourteen studies are for electric utility repowering of existing oil or natural gas generating plants. The other six are the first site-specific studies of the use of solar central receiver systems for industrial process heat. The industrial processes include gypsum board drying, oil refining, enhanced oil recovery, uranium ore processing, natural gas processing, and ammonia production. Site descriptions, project summaries, conceptual designs, and functional descriptions are given for each of these 14 studies.

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Sandia Laboratories radiation facilities. Second edition

O'Canna, Myra L.

This brochure is designed as a basic source of information for prospective users of Sandia Laboratories Radiation Facilities. It contains a brief description of the various major radiation sources, a summary of their output characteristics, and additional information useful to experimenters. Radiation source development and source upgrading is an ongoing program, with new source configurations and modes of operation continually being devised to satisfy the ever-changing radiation requirements of the users. For most cases, the information presented here should allow a potential user to assess the applicability of a particular radiation facility to a proposed experiment and to permit some preirradiation calculations and planning.

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Particle beam fusion research at Sandia National Laboratories

O'Canna, Myra L.

Sandia`s Particle Beam Fusion Program is investigating several driver options, based on pulsed power technology, with the goal of demonstrating a practical ignitor for Inertial Confinement Fusion (ICF) Reactors. The interrelated aspects of power conditioning and compression, beam-target interaction, and target ignition are being studied. The issues of efficiency, reliability and multiple pulse capability are being integrated into the program to provide a viable approach to an experimental power reactor. On a shorter time scale the authors expect to derive important military-related benefits from attendant research and facility development. The two most important advantages of pulsed power driven fusion are the inherent low cost and high efficiency of high current particle accelerators. However, comparison of the relative merits of particle beams and focused laser beams must include many other factors such as beam transport, and target coupling, as well as target design and fabrication. These issues are being investigated to determine if the perceived practical benefits of particle beam fusion can indeed be realized. The practical considerations are exemplified in a comparison of the leading ICF drivers. The plan being followed by Sandia involves using the Electron Beam Fusion Accelerator (EBFA) to meet three objectives by 1985: significant burn using EBFA 1, net energy gain based on an upgrade of EBFA to the 2 megajoule (MJ) level (EBFA 2), and demonstration of a single module of EBFA 2 operated in the repetitive pulse mode. These goals are dependent, of course, on success in solving several key technical problems under investigation. If these technical problems can be solved, then practical applications to fusion power could be considered. The potential for these applications has been studied using economic models that allow one to derive the cost of power based on various assumptions.

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Flexible armored blanket development

O'Canna, Myra L.

An exploratory development contract was undertaken on December 23, 1977 which had as its purpose the development and demonstration of a flexible armored blanket design suitable for providing ballistic protection to nuclear weapons during shipment. Objectives were to design and fabricate a prototype blanket which will conform to the weapon shape, is troop-handleable in the field, and which, singly or in multiple layers, can defeat a range of kinetic energy armor piercing (AP) ammunition potentially capable of damaging the critical portion of the nuclear weapon. Following empirical testing, including the firing of threat ammunition under controlled laboratory and field test conditions, materials were selected and assembled into two blanket designs, each weighing approximately 54 kg/m{sup 2} (11 lbs/ft{sup 2}) and estimated to cost from $111 to $180 per ft{sup 2} in production. A firing demonstration to evidence blanket performance against terrorist/light infantry weapons, heavy infantry weapons, and aircraft cannon was conducted for representatives of the DOD and interested Sandia employees on April 12, 1978. The blankets performed better than anticipated defeating bullets up to 7.62 mm x 51 mm AP with one layer and projectiles up to 23 mm HEI with two layers. Based on these preliminary tests it is recommended that development work be continued with the following objectives: (1) the selection by the DOD of priority applications, (2) the specific design and fabrication of sufficient quantities of armored blankets for field testing, (3) the evaluation of the blankets by DOD operational units, with reports to Sandia Laboratories to enable final design.

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Results 99126–99150 of 99,299
Results 99126–99150 of 99,299