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Physical adsorption: rare gas atoms on solid surfaces. Progress report, June 1, 1980-May 31, 1981

Description: This project has entailed investigation of three areas during the current term: physical adsorption, photostimulated field emission (PSE), and phonon reflection at interfaces. The principal effort has been directed toward understanding interactions associated with physical adsorption and the associated properties of a film. The specific topics pursued include the detailed form of the long range interaction, the configuration space wave function, and the interaction between adatoms. Experimental confirmation of the last two come from neutron scattering and thermodynamic measurements, respectively. The research in PSE has yielded results which improve upon previous calculations. There is, however, a remaining disagreement with experiment; suggestions for the origin are discussed. The phonon reflection work is directed toward understanding the role of surface roughness, an important factor in increasing the energy transmission across interfaces. A formalism has been developed which will be evaluated in the future.
Date: February 1, 1981
Creator: Cole, M.W.
Partner: UNT Libraries Government Documents Department

Internal Technical Report, Software Requirements and Design Guide for the 5MW(e) Raft River Pilot Plant

Description: The 5MW(e) electrical generating plant is a demonstrational unit intended to provide engineering data basic to improvement of geothermal-electric technology. It is anticipated that the plant will operate on a production basis after initial testing, and that periodic re-testing will be done to measure the effects of fouling in heat exchanges and aging generally. The initial tests will confirm engineering estimates of performance, and will identify optimum feasible operatinq conditions and maximum power generating capacity. They will also identify any anomalous plant behavior not foreseen. Several tests will lead to quantification of constant and variable terms used in thermodynamic relationships descriptive of plant and subsystem behavior. Because the product of the testing will be confirmatory engineering data heretofore unavailable, the plant has been carefully instrumented, with either explicit or implicit instrumentation redundancy for most parameters to be measured. The 5MW(e) data system collects the data directly from the instrumentation. Enhancements such as on-line analytical routines may be added later, but initially, data capture shall be the sole activity of the data system. The 5MW(e) plant converts the energy of geothermally heated water to electrical energy conforming to 60 Hz commercial power standards. The plant capacity is sufficiently large to be useful in a demonstrational sense, but is limited to a capacity conservative of the geothermal energy resource, which hasn't been fully explored. The 5MW(e) plant will continue on a regular production basis after completion of the testing. Additional production units may be added at a later time.
Date: May 15, 1980
Creator: Metcalf, D.D. & Cole, M.S.
Partner: UNT Libraries Government Documents Department

Fabrication of the helical field coil components for the advanced toroidal facility

Description: The fabrication techniques used to manufacture the major components of the helical field (HF) coil segments for the Advanced Toroidal Facility (ATF) are described. The major components of an HF coil segment are 14 water-cooled, copper conductors and a T-shaped stainless steel support member (or ''tee''). Twenty-four of these segments were used in the fabrication of two coils for the ATF experiment. The helical shape, accurate position requirements, large size, and potential for high cost required unique approaches to the fabrication of these components. One method of fabrication was to use 44-mm-thick (standard size) plate to form the base and leg of the tee and to join the sections by welding. Because of the tolerance requirements, a thicker plate (70 mm) was used and then contour machined to the final shape. The second approach, conducted in parallel with the first, was to cast the tee as a single piece. The first attempts were to make the casting larger than required, then machine it to final size and shape. The cost of machining either the welded tee or the cast tee was extremely high, so several prototypes were fabricated until a cast tee that required no contour machining was produced. The shape and positional requirements were also the major problems in fabricating the copper conductors, or turns. The approach taken was to make an accurate fixture and position the turns in the fixture, then anneal to remove residual stresses and form the copper turns to the shape of the fixture. The lessons learned in pursuing these fabrication methods are presented. 5 refs., 3 figs.
Date: January 1, 1987
Creator: Cole, M.J.; Whitson, J.C. & Banks, B.J.
Partner: UNT Libraries Government Documents Department

Results of Compact Stellarator Engineering Trade Studies

Description: number of technical requirements and performance criteria can drive stellarator costs, e.g., tight tolerances, accurate coil positioning, low aspect ratio (compactness), choice of assembly strategy, metrology, and complexity of the stellarator coil geometry. With the completion of a seven-year design and construction effort of the National Compact Stellarator Experiment (NCSX) it is useful to interject the NCSX experience along with the collective experiences of the NCSX stellarator community to improving the stellarator configuration. Can improvements in maintenance be achieved by altering the stellarator magnet configuration with changes in the coil shape or with the combination of trim coils? Can a mechanical configuration be identified that incorporates a partial set of shaped fixed stellarator coils along with some removable coil set to enhance the overall machine maintenance? Are there other approaches that will simplify the concepts, improve access for maintenance, reduce overall cost and improve the reliability of a stellarator based power plant? Using ARIES-CS and NCSX as reference cases, alternative approaches have been studied and developed to show how these modifications would favorably impact the stellarator power plant and experimental projects. The current status of the alternate stellarator configurations being developed will be described and a comparison made to the recently designed and partially built NCSX device and the ARIES-CS reactor design study.
Date: May 27, 2009
Creator: Brown, Tom; Bromberg, L. & Cole, M.
Partner: UNT Libraries Government Documents Department

Initial results from a folded waveguide ICRF antenna development project

Description: A folded waveguide (FWG) ICRF launcher has been built and preliminary high power tests completed. This project is intended to provide a proof-of-principle test, using a high density plasma load, of the high power density capability and other ITER-relevant advanced features of the FWG. The design is a 12 vane, 57 MHz unit with a quarter-wavelength resonator configuration. This FWG has a 0.31 m square cross section that can be installed with either fast wave or ion-Bernstein wave polarization and can also be retracted behind a vacuum isolation valve. A primary issue to be addressed by this project is the plasma loading and maximum power capability of the FWG. Initial high power tests on the ORNL Radio Frequency Test Facility have been conducted. Modeling of the FWG electromagnetic fields and calculations of loading have been performed as well as an investigation of alternate face plate designs that improve the coupling by allowing greater magnetic field penetration into the plasma. This FWG was originally designed for TFTR or PBX-M and is now being considered for the DIII-D tokamak at GA, the NSTX small aspect ratio device under construction at PPPL and the possible FSX experiment at PPPL.
Date: August 1, 1997
Creator: Bigelow, T.S.; Cole, M.J. & Fadnek, A.
Partner: UNT Libraries Government Documents Department

Design Construction and Test Results of a HTS Solenoid For Energy Recovery Linac

Description: An innovative feature of the proposed Energy Recovery Linac (ERL) is the use of a solenoid made with High Temperature Superconductor (HTS) with the Superconducting RF cavity. The use of HTS allows solenoid to be placed in close proximity to the cavity and thus provides early focusing of the electron beam. In addition, cryogenic testing at {approx}77 K is simpler and cheaper than 4 K testing. This paper will present the design, construction and test results of this HTS solenoid. The HTS solenoid in the proposed ERL will be situated in the transition region between the superconducting cavity at {approx}4 K and the cryostat at the room temperature. Solenoid inside the cryogenic structure provides an early focusing and hence low emittance beam. The temperature in the transition region will be too high for a conventional low temperature superconductor and resistive heat load from copper coils will be too high on cryogenic system. HTS coils also allow much higher current density and significant reduction in size as compared to copper coils. Hence HTS solenoid provide a unique and technically superior solution. The use of a HTS solenoid with superconducting cavity offers a unique option as it can be placed in a cold to warm transition region to provide early focussing without using additional space. Construction and test results so far are very encouraging for its use in the ERL project.
Date: March 28, 2011
Creator: Anerella, M; Ben-Zvi, I; Kayran, D; McIntyre, G; Muratore, J; Plate, S et al.
Partner: UNT Libraries Government Documents Department

Corrosion studies of titanium in borated water for TPX

Description: Corrosion testing was performed to demonstrate the compatibility of the titanium vacuum vessel with borated water. Borated water is proposed to fill the annulus of the double wall vacuum vessel to provide effective radiation shielding. Borating the water with 110 grams of boric acid per liter is sufficient to reduce the nuclear heating in the Toroidal Field Coil set and limit the activation of components external to the vacuum vessel. Constant extension rate tensile (CERT) and electrochemical potentiodynamic tests were performed. Results of the CERT tests confirm that stress corrosion cracking is not significant for Ti-6Al4V or Ti-3AI-2.5V. Welded and unwelded specimens were tested in air and in borated water at 150{degree}C. Strength, elongation, and time to failure were nearly identical for all test conditions, and all the samples exhibited ductile failure. Potentiodynamic tests on Ti-6A1-4V and Ti in borated water as a function of temperature showed low corrosion rates over a wide passive potential range. Further, this passivity appeared stable to anodic potentials substantially greater than those expected from MHD effects.
Date: December 31, 1995
Creator: Wilson, D.F.; Pawel, S.J.; DeVan, J.H.; Cole, M.J. & Nelson, B.E.
Partner: UNT Libraries Government Documents Department

Helical coil alignment in the advanced toroidal facility

Description: This paper presents a brief overview of the helical coil design concept, detailed descriptions of the method for installation and alignment, and discussions of segment installation and alignment equipment. Alignment is accomplished by optical methods using electronic theodolites connected to a microcomputer to form a coordinate measurement system. The coordinate measurement system is described in detail, along with target selection and fixturing for manipulation of the helical coil segments during installation. In addition, software is described including vendor-supplied software used in the coordinate measurement system and in-house-developed software used to calibrate segment and positioning fixture motion. 2 refs., 8 figs.
Date: January 1, 1985
Creator: Taylor, D.J.; Cole, M.J.; Johnson, R.L.; Nelson, B.E.; Warwick, J.E. & Whitson, J.C.
Partner: UNT Libraries Government Documents Department

Thermodynamic implications of band structure effects for rare gases on graphite

Description: Recent analyses of atomic beam scattering data have suggested that an anisotropic He-C pair interaction is appropriate to the problem of He on graphite. This results in considerably more corrugated equipotential surfaces than previously assumed, and correspondingly manifest band structure effects. These have been observed for He/graphite in the specific heat for temperature T > 3/sup 0/K. The implications for other gases and temperatures and for the effective adatom-adatom interaction are discussed.
Date: January 1, 1980
Creator: Carlos, W.E.; Cole, M.W.; Rauber, S.; Vidali, G.; Silva-Moreira, A.F.; Codona, J.L. et al.
Partner: UNT Libraries Government Documents Department

Interpretation of Wild 2 Dust Fine Structure: Comparison of Stardust Aluminium Foil Craters to the Three-Dimensional Shape of Experimental Impacts by Artificial Aggregate Particles and Meteorite Powders

Description: New experimental results show that Stardust crater morphology is consistent with interpretation of many larger Wild 2 dust grains being aggregates, albeit most of low porosity and therefore relatively high density. The majority of large Stardust grains (i.e. those carrying most of the cometary dust mass) probably had density of 2.4 g cm{sup -3} (similar to soda-lime glass used in earlier calibration experiments) or greater, and porosity of 25% or less, akin to consolidated carbonaceous chondrite meteorites, and much lower than the 80% suggested for fractal dust aggregates. Although better size calibration is required for interpretation of the very smallest impacting grains, we suggest that aggregates could have dense components dominated by {micro}m-scale and smaller sub-grains. If porosity of the Wild 2 nucleus is high, with similar bulk density to other comets, much of the pore-space may be at a scale of tens of micrometers, between coarser, denser grains. Successful demonstration of aggregate projectile impacts in the laboratory now opens the possibility of experiments to further constrain the conditions for creation of bulbous (Type C) tracks in aerogel, which we have observed in recent shots. We are also using mixed mineral aggregates to document differential survival of pristine composition and crystalline structure in diverse fine-grained components of aggregate cometary dust analogues, impacted onto both foil and aerogel under Stardust encounter conditions.
Date: December 10, 2009
Creator: Kearsley, A T; Burchell, M J; Price, M C; Graham, G A; Wozniakiewicz, P J; Cole, M J et al.
Partner: UNT Libraries Government Documents Department

Diagnostics Plan for the National Compact Stellarator Experiment

Description: The National Compact Stellarator Experiment (NCSX) is a stellarator-tokamak hybrid seeking to combine the good confinement, high beta and moderate aspect ratio of the tokamak with the quasi-steady-state operation and good stability properties of the stellarator. A preliminary list of measurement requirements, intended to satisfy the needs of the phased research plan, provides the basis for a full complement of plasma diagnostics. It is important to consider this full set, even at this early stage, to assess the adequacy of the stellarator design for diagnostic port access. The 3-D nature of the plasma is a measurement challenge, as is the necessity for high spatial resolution to assess the quality of magnetic surfaces. Other diagnostic requirements include the need for re-entrant views that penetrate the cryostat, for a convenient e-beam probe for field line mapping, and for a diagnostic neutral beam for active spectroscopy.
Date: July 12, 2002
Creator: Johnson, D.; Brown, T.; Neilson, H.; Schilling, G.; Takahashi, H.; Zarnstorff, M. et al.
Partner: UNT Libraries Government Documents Department

Design, analysis, and testing of a high thermal conductivity waveguide window for use in a free-electron laser

Description: Design, analysis and testing of a waveguide window with a goal of propagating greater than 100 kW average power operating at 1500 Mhz has been performed. This is made possible by the favorable material properties of Beryllia (BeO). Brazing the window to a soft copper frame and then brazing the frame to a KOVAR flange provides the vacuum seal. RF analysis combined with thermal/structural analysis shows the benefits of the material. The KOVAR flange with a CTE,coefficient of thermal expansion, that matches that of BeO enables a strong braze joint. RF testing to 35 kW has been successful, and higher powers will be tested in the near future. The basics of this design can be expanded to applications with lower frequencies and higher average power.
Date: August 1, 1998
Creator: Schultheiss, T.; Christina, V.; Cole, M.; Rathke, J.; Elliott, T.; Nguyen, V. et al.
Partner: UNT Libraries Government Documents Department

A high thermal conductivity waveguide window for use in a free electron laser

Description: Design, analysis, and testing of a waveguide window with a goal of propagating greater than 100 kW average power operating at 1500 Mhz has been performed. This is made possible by the favorable material properties of beryllia (BeO). Brazing the window to a soft copper frame and then brazing the frame to a KOVAR flange provides the vacuum seal. RF analysis combined with thermal/structural analysis shows the benefits of the material. The KOVAR flange with a CTE, coefficient of thermal expansion, that matches that of BeO enables a strong braze joint. RF testing to 35 kW has been successful. The basics of this design can be expanded to applications with lower frequencies and higher average power. A paper similar to this was presented at LINAC 98.
Date: April 1, 1999
Creator: Elliott, T.; Nguyen, V.; Phillips, L.; Lab), J. Preble (Jefferson; Schultheiss, T.; Christina, V. et al.
Partner: UNT Libraries Government Documents Department

RF DESIGN AND OPERATING PERFORMANCE OF THE BNL/AES 1.3 GHZ SINGLE CELL SUPERCONDUCTING RF PHOTOCATHODE ELECTRON GUN.

Description: Over the past several years Advanced Energy Systems and BNL have been collaborating on the development and testing of a fully superconducting photocathode electron gun. Over the past year we have begun to realize significant results which have been published elsewhere [1]. This paper will review the RF design of the gun under test and present results of its performance under various operating conditions. Results for cavity quality factor will be presented for various operating temperatures and cavity field gradients. We will also discuss future plans for testing using this gun.
Date: May 16, 2005
Creator: COLE, M.; KNEISEL, P.; BEN-ZVI, I.; BURRILL, A.; HAHN, G.; RAO, T. et al.
Partner: UNT Libraries Government Documents Department

Design description of the helical field coils for the Advanced Toroidal Facility

Description: The Helical Field (HF) Coils for the Advanced Toroidal Facility will consist of two coils, which wrap around the plasma six times. The major radius of the coils will be 2.1 m with a minor radius of 45.75 cm to the coil current center. The coils will be positioned at assembly to within a 2 mm diameter around the winding law, Theta = 1/6 Phi. The coils will be fabricated as a set of 24 identical segments, 12 upper segments and 12 lower segments. These segments will be joined into continuous coils at the installation site by means of field assembled joints at the horizontal centerline of the machine. One special joint on each coil will contain the coil leads. The HF coils will consist of 14 copper turns and a structural member of stainless steel which has a cross section in the shape of a T. These pieces will be fabricated in accordance with the winding law Theta = 1/6 Phi. The copper turns will be water cooled and formed from CDA 101 or 102 copper. The 14 copper turns will be positioned such that 7 turns will be placed on each side of the structural tee. The structural tee will be fabricated from 44.45 mm thick stainless steel with a minimum yield strength of 205 MPa and a tensile strength of 485 MPa.
Date: January 1, 1983
Creator: Cole, M.J.; Thompson, P.B.; Jernigan, T.C.; Nelson, B.E.; Vinyard, L.M.; Johnson, R.L. et al.
Partner: UNT Libraries Government Documents Department

Field evaluation of sampling methods for pressurized geothermal liquids, gases, and suspended solids

Description: Many different sampling methods were tested and compared for collecting samples for measurement of brine chemistry, gases, and suspended solids from pressurized geothermal systems. The tests were conducted on the 6-2 wellhead and a test loop at the Department of Energy's Geothermal Test Facility at East Mesa, California. The recommended methods for single-phase liquid or single-phase steam (with gases) are presented, together with detailed procedures. The results of testing methods for sampling two phase liquid-steam systems showed significant errors can result. It was recommended that two-phase flowing wells be directed to a full flow separator and the single-phase liquid and single-phase steam sampled separately using the recommended methods.
Date: January 1, 1980
Creator: Shannon, D.W.; Cole, M.W.; DeMonia, D.D.; Divine, J.R.; Jensen, G.A.; Kindle, C.H. et al.
Partner: UNT Libraries Government Documents Department

Design and Fabrication of the RHIC Electron-Cooling Experiment High Beta Cavity and Cryomodule

Description: The summary of this report is: (1) A high-current SRF cavity for an Energy Recovery Linac (ERL) has been designed by BNL and AES and fabricated by AES; (2) The cavity was cleaned and tested by JLAB with BNL personnel support; (3) Cavity performance exceeded goal of 20 MV/m at Q{sub 0} > 1 x 10{sup 10} and far exceeded requirement of 15 MV/m at Q{sub 0} > 1 x 10{sup 10}; (4) Hermetic String assembled at JLAB with BNL personnel support and shipped to BNL; and (5) BNL has recently completed Cryomodule assembly and unit is ready for installation in the ERL vault.
Date: November 17, 2008
Creator: Holmes,D.; Calderaro, M.; Cole, M.; Falletta, M.; Peterson, E.; Rathke, J. et al.
Partner: UNT Libraries Government Documents Department

NCSX Vacuum Vessel Fabrication

Description: The National Compact Stellarator Experiment (NCSX) is being constructed at the Princeton Plasma Physics Laboratory (PPPL) in conjunction with the Oak Ridge National Laboratory (ORNL). The goal of this experiment is to develop a device which has the steady state properties of a traditional stellarator along with the high performance characteristics of a tokamak. A key element of this device is its highly shaped Inconel 625 vacuum vessel. This paper describes the manufacturing of the vessel. The vessel is being fabricated by Major Tool and Machine, Inc. (MTM) in three identical 120º vessel segments, corresponding to the three NCSX field periods, in order to accommodate assembly of the device. The port extensions are welded on, leak checked, cut off within 1" of the vessel surface at MTM and then reattached at PPPL, to accommodate assembly of the close-fitting modular coils that surround the vessel. The 120º vessel segments are formed by welding two 60º segments together. Each 60º segment is fabricated by welding ten press-formed panels together over a collapsible welding fixture which is needed to precisely position the panels. The vessel is joined at assembly by welding via custom machined 8" (20.3 cm) wide spacer "spool pieces." The vessel must have a total leak rate less than 5 X 10-6 t-l/s, magnetic permeability less than 1.02μ, and its contours must be within 0.188" (4.76 mm). It is scheduled for completion in January 2006.
Date: October 7, 2005
Creator: Viola, M. E.; Brown, T.; Heitzenroeder, P.; Malinowski, F.; Reiersen, W.; Sutton, L. et al.
Partner: UNT Libraries Government Documents Department

Progress In NCSX and QPS Design and Construction

Description: The National Compact Stellarator Experiment (NCSX) is being constructed at the Princeton Plasma Physics Laboratory (PPPL) in partnership with the Oak Ridge National Laboratory (ORNL). The stellarator core is designed to produce a compact 3-D plasma that combines stellarator and tokamak physics advantages. The engineering challenges of NCSX stem from its complex geometry. From the project's start in April, 2003 to September, 2004, the fabrication specifications for the project's two long-lead components, the modular coil winding forms and the vacuum vessel, were developed. An industrial manufacturing R&D program refined the processes for their fabrication as well as production cost and schedule estimates. The project passed a series of reviews and established its performance baseline with the Department of Energy. In September 2004, fabrication was approved and contracts for these components were awarded. The suppliers have completed the engineering and tooling preparations and are in production. Meanwhile, the project completed preparations for winding the coils at PPPL by installing a coil manufacturing facility and developing all necessary processes through R&D. The main activities for the next two years will be component manufacture, coil winding, and sub-assembly of the vacuum vessel and coil subsets. Machine sector sub-assembly, machine assembly, and testing will follow, leading to First Plasma in July 2009.
Date: October 20, 2005
Creator: Reiersen, W.; Heitzenroeder, P.; Neilson, G. H.; Nelson, B.; Zarnstorff, M.; Brown, T. et al.
Partner: UNT Libraries Government Documents Department

TUNING SECTION 2 OF THE LEDA CCDTL

Description: As part of the Low-Energy Demonstration Accelerator (LEDA) portion of the Advanced Accelerator Applications (AAA) project we have fabricated and will perform high-power RF tests on Section 2 of the 700-MHz Coupled-Cavity Drift-Tube Linac (CCDTL). This CCDTL section contains six, two-gap accelerating cells. This portion of the CCDTL was designed to accelerate the 100-mA, LEDA RFQ proton beam to 7.3 MeV. This paper reports on the process and results of tuning Section 2 leading up to high-power RF testing.
Date: January 1, 2001
Creator: Rybarcyk, L. J. (Lawrence J.); L.), Wood R. L. (Richard; Leslie, P. O. (Paul O.); Valdiviez, R. (Robert); Cole, M. D. (Michael D.) & Potter, J. M. (James M.)
Partner: UNT Libraries Government Documents Department

Analytical Scanning and Transmission Electron Microscopy of Laboratory Impacts on Stardust Aluminium Foils: Interpreting Impact Crater Morphology and the Composition of Impact Residues.

Description: The known encounter velocity (6.1kms{sup -1}) between the Stardust spacecraft and the dust emanating from the nucleus of comet Wild 2 has allowed realistic simulation of dust collection in laboratory experiments designed to validate analytical methods for the interpretation of dust impacts on the aluminium foil components of the Stardust collector. In this report we present information on crater gross morphology, the pre-existing major and trace element composition of the foil, geometrical issues for energy dispersive X-ray analysis of the impact residues in scanning electron microscopes, and the modification of dust chemical composition during creation of impact craters as revealed by analytical transmission electron microscopy. Together, these observations help to underpin the interpretation of size, density and composition for particles impacted upon the Stardust aluminium foils.
Date: October 19, 2006
Creator: Kearsley, A T; Graham, G A; Burchell, M J; Cole, M J; Dai, Z R; Teslich, N et al.
Partner: UNT Libraries Government Documents Department

Design Of JET ELM Control Coils For Operation At 350 C

Description: A study has confirmed the feasibility of designing, fabricating and installing resonant magnetic field perturbation (RMP) coils in JET1 with the objective of controlling edge localized modes (ELM). A system of two rows of in-vessel coils, above the machine midplane, has been chosen as it not only can investigate the physics of and achieve the empirical criteria for ELM suppression, but also permits variation of the spectra allowing for comparison with other experiments. These coils present several engineering challenges. Conditions in JET necessitate the installation of these coils via remote handling, which will impose weight, dimensional and logistical limitations. And while the encased coils are designed to be conventionally wound and bonded, they will not have the usual benefit of active cooling. Accordingly, coil temperatures are expected to reach 350 C during bakeout as well as during plasma operations. These elevated temperatures are beyond the safe operating limits of conventional OFHC copper and the epoxies that bond and insulate the turns of typical coils. This has necessitated the use of an alternative copper alloy conductor C18150 (CuCrZr). More importantly, an alternative to epoxy had to be found. An R&D program was initiated to find the best available insulating and bonding material. The search included polyimides and ceramic polymers. The scope and status of this R&D program, as well as the critical engineering issues encountered to date are reviewed and discussed.
Date: September 20, 2010
Creator: Zatz, I. J.; Brooks, A.; Cole, M.; Neilson, G. H.; Lowry, C.; Mardenfeld, M. et al.
Partner: UNT Libraries Government Documents Department