Sample records for vortex tube project

  1. Heat Transfer Enhancement for Finned-Tube Heat Exchangers with Vortex Generators: Experimental and Numerical Results

    SciTech Connect (OSTI)

    O'Brien, James Edward; Sohal, Manohar Singh; Huff, George Albert

    2002-08-01T23:59:59.000Z

    A combined experimental and numerical investigation is under way to investigate heat transfer enhancement techniques that may be applicable to large-scale air-cooled condensers such as those used in geothermal power applications. The research is focused on whether air-side heat transfer can be improved through the use of finsurface vortex generators (winglets,) while maintaining low heat exchanger pressure drop. A transient heat transfer visualization and measurement technique has been employed in order to obtain detailed distributions of local heat transfer coefficients on model fin surfaces. Pressure drop measurements have also been acquired in a separate multiple-tube row apparatus. In addition, numerical modeling techniques have been developed to allow prediction of local and average heat transfer for these low-Reynolds-number flows with and without winglets. Representative experimental and numerical results presented in this paper reveal quantitative details of local fin-surface heat transfer in the vicinity of a circular tube with a single delta winglet pair downstream of the cylinder. The winglets were triangular (delta) with a 1:2 height/length aspect ratio and a height equal to 90% of the channel height. Overall mean fin-surface Nusselt-number results indicate a significant level of heat transfer enhancement (average enhancement ratio 35%) associated with the deployment of the winglets with oval tubes. Pressure drop measurements have also been obtained for a variety of tube and winglet configurations using a single-channel flow apparatus that includes four tube rows in a staggered array. Comparisons of heat transfer and pressure drop results for the elliptical tube versus a circular tube with and without winglets are provided. Heat transfer and pressure-drop results have been obtained for flow Reynolds numbers based on channel height and mean flow velocity ranging from 700 to 6500.

  2. Experimental Characterization of the Full Load Vortex Rope Pulsation in the Draft Tube of a Francis Turbine

    E-Print Network [OSTI]

    Turbine Objective Francis turbines working in off design operating conditions may experience the formation the stability of the machine operation, since it is a major source of pressure fluctuation in the hydraulic of the draft tube on a reduce scale model of a Francis turbine operating at full load. In particular

  3. Decontamination and dismantlement of the building 200/205 pneumatic transfer tube at Argonne National Laboratory-East project final report.

    SciTech Connect (OSTI)

    Wiese, E. C.

    1998-12-11T23:59:59.000Z

    The Building 200/205 Pneumatic Transfer Tube D&D Project was directed toward the following goals: Remove any radioactive and hazardous materials associated with the transfer tube; Survey the transfer tube to identify any external contamination; Remove the transfer tube and package for disposal; Survey the soil and sand surrounding the transfer tube for any contamination; and Backfill the trench in which the tube sat and restore the area to its original condition. These goals had been set in order to eliminate the radiological and hazardous safety concerns inherent in the buried transfer tube and to allow, upon completion of the project, the removal of this project from the ANL-E action item list. The physical condition of the transfer tube and possible nuclear fuel samples lost in the tube were the primary areas of concern, while the exact location of the transfer tube was of secondary concern. ANL-E health physics technicians collected characterization data from the ends of the Building 200/205 pneumatic transfer tube in January 1998. The characterization surveys identified contamination to a level of 67,000 dpm (1,117 Bq) ({beta}/{gamma}) and 20,000 dpm (333 Bq) {alpha} smearable at the opening.

  4. Vortex methods and vortex statistics

    SciTech Connect (OSTI)

    Chorin, A.J.

    1993-05-01T23:59:59.000Z

    Vortex methods originated from the observation that in incompressible, inviscid, isentropic flow vorticity (or, more accurately, circulation) is a conserved quantity, as can be readily deduced from the absence of tangential stresses. Thus if the vorticity is known at time t = 0, one can deduce the flow at a later time by simply following it around. In this narrow context, a vortex method is a numerical method that makes use of this observation. Even more generally, the analysis of vortex methods leads, to problems that are closely related to problems in quantum physics and field theory, as well as in harmonic analysis. A broad enough definition of vortex methods ends up by encompassing much of science. Even the purely computational aspects of vortex methods encompass a range of ideas for which vorticity may not be the best unifying theme. The author restricts himself in these lectures to a special class of numerical vortex methods, those that are based on a Lagrangian transport of vorticity in hydrodynamics by smoothed particles (``blobs``) and those whose understanding contributes to the understanding of blob methods. Vortex methods for inviscid flow lead to systems of ordinary differential equations that can be readily clothed in Hamiltonian form, both in three and two space dimensions, and they can preserve exactly a number of invariants of the Euler equations, including topological invariants. Their viscous versions resemble Langevin equations. As a result, they provide a very useful cartoon of statistical hydrodynamics, i.e., of turbulence, one that can to some extent be analyzed analytically and more importantly, explored numerically, with important implications also for superfluids, superconductors, and even polymers. In the authors view, vortex ``blob`` methods provide the most promising path to the understanding of these phenomena.

  5. Vortex methods

    SciTech Connect (OSTI)

    Chorin, A.J. [California Univ., Berkeley, CA (United States). Dept. of Mathematics]|[Lawrence Berkeley Lab., CA (United States)

    1993-06-01T23:59:59.000Z

    Vortex methods originated from the observation that in incompressible inviscid flow vorticity (or, more accurately, circulation) is a conserved quantity, as can be readily deduced from the absence of tangential stresses. Thus, if the vorticity is known at time t=0, one can find the flow at a later time by simply following the vorticity. In this narrow context, a vortex method is a numerical method that follows vorticity. The author restricts himself in these lectures to a special class of numerical vortex methods, those that are based on a Lagrangian transport of vorticity in hydrodynamics by smoothed particles (blobs) and those whose analysis contributes to the understanding of blob methods. Blob methods started in the 1930`s.

  6. Electron tube

    DOE Patents [OSTI]

    Suyama, Motohiro (Hamamatsu, JP); Fukasawa, Atsuhito (Hamamatsu, JP); Arisaka, Katsushi (Los Angeles, CA); Wang, Hanguo (North Hills, CA)

    2011-12-20T23:59:59.000Z

    An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

  7. Liquid Vortex Shielding for Fusion Energy Applications

    SciTech Connect (OSTI)

    Bardet, Philippe M. [University of California, Berkeley (United States); Supiot, Boris F. [University of California, Berkeley (United States); Peterson, Per F. [University of California, Berkeley (United States); Savas, Oemer [University of California, Berkeley (United States)

    2005-05-15T23:59:59.000Z

    Swirling liquid vortices can be used in fusion chambers to protect their first walls and critical elements from the harmful conditions resulting from fusion reactions. The beam tube structures in heavy ion fusion (HIF) must be shielded from high energy particles, such as neutrons, x-rays and vaporized coolant, that will cause damage. Here an annular wall jet, or vortex tube, is proposed for shielding and is generated by injecting liquid tangent to the inner surface of the tube both azimuthally and axially. Its effectiveness is closely related to the vortex tube flow properties. 3-D particle image velocimetry (PIV) is being conducted to precisely characterize its turbulent structure. The concept of annular vortex flow can be extended to a larger scale to serve as a liquid blanket for other inertial fusion and even magnetic fusion systems. For this purpose a periodic arrangement of injection and suction holes around the chamber circumference are used, generating the layer. Because it is important to match the index of refraction of the fluid with the tube material for optical measurement like PIV, a low viscosity mineral oil was identified and used that can also be employed to do scaled experiments of molten salts at high temperature.

  8. Reconnection of vortex filaments and Kolmogorov spectrum

    E-Print Network [OSTI]

    Sergey K. Nemirovskii

    2014-04-19T23:59:59.000Z

    The energy spectrum of the 3D velocity field, induced by collapsing vortex filaments is studied. One of the aims of this work is to clarify the appearance of the Kolmogorov type energy spectrum $E(k)\\varpropto k^{-5/3}$, observed in many numerical works on discrete vortex tubes (quantized vortex filaments in quantum fluids). Usually, explaining classical turbulent properties of quantum turbulence, the model of vortex bundles, is used. This model is necessary to mimic the vortex stretching, which is responsible for the energy transfer in classical turbulence. In our consideration we do not appeal to the possible "bundle arrangement" but explore alternative idea that the turbulent spectra appear from singular solution, which describe the collapsing line at moments of reconnection. One more aim is related to an important and intensively discussed topic - a role of hydrodynamic collapse in the formation of turbulent spectra. We demonstrated that the specific vortex filament configuration generated the spectrum $E(k)$ close to the Kolmogorov dependence and discussed the reason for this as well as the reason for deviation. We also discuss the obtained results from point of view of the both classical and quantum turbulence.

  9. TORP (Tertiary Oil Recovery Project) stream tube model for waterflood performance calculations in a reservoir with arbitrary well patterns and irregular boundaries

    SciTech Connect (OSTI)

    Vossoughi, S.

    1981-01-01T23:59:59.000Z

    The Tertiary Oil Recovery Project stream tube model was developed as a tool to help oil operators in Kansas evaluate and understand their waterflood projects in a more systematic approach. The model utilizes the stream tube concept and Buckley-Leverett theory and can be applied to any homogeneous reservoir with arbitrary well patterns and regular or irregular boundaries. It also can be applied to tracer projects to estimate tracer breakthrough time if the tracer is injected during the stage of high water-oil ratio. The computer package has been prepared in a fashion such that minimum effort and interaction are required for the user to obtain the final results from specified input data. The model was applied to an example problem consisting of a 5-spot pattern. 19 references.

  10. Improved vortex reactor system

    DOE Patents [OSTI]

    Diebold, James P. (Lakewood, CO); Scahill, John W. (Evergreen, CO)

    1995-01-01T23:59:59.000Z

    An improved vortex reactor system for affecting fast pyrolysis of biomass and Refuse Derived Fuel (RDF) feed materials comprising: a vortex reactor having its axis vertically disposed in relation to a jet of a horizontally disposed steam ejector that impels feed materials from a feeder and solids from a recycle loop along with a motive gas into a top part of said reactor.

  11. Vortex diode jet

    DOE Patents [OSTI]

    Houck, Edward D. (Idaho Falls, ID)

    1994-01-01T23:59:59.000Z

    A fluid transfer system that combines a vortex diode with a jet ejector to transfer liquid from one tank to a second tank by a gas pressurization method having no moving mechanical parts in the fluid system. The vortex diode is a device that has a high resistance to flow in one direction and a low resistance to flow in the other.

  12. Flux tubes in the SU(3) vacuum

    E-Print Network [OSTI]

    Mario S. Cardaci; Paolo Cea; Leonardo Cosmai; Rossella Falcone; Alessandro Papa

    2011-09-30T23:59:59.000Z

    We analyze the distribution of the chromoelectric field generated by a static quark-antiquark pair in the SU(3) vacuum. We find that the transverse profile of the flux tube resembles the dual version of the Abrikosov vortex field distribution and give an estimate of the London penetration length in the confined vacuum.

  13. Improved vortex reactor system

    DOE Patents [OSTI]

    Diebold, J.P.; Scahill, J.W.

    1995-05-09T23:59:59.000Z

    An improved vortex reactor system is described for affecting fast pyrolysis of biomass and Refuse Derived Fuel (RDF) feed materials comprising: a vortex reactor having its axis vertically disposed in relation to a jet of a horizontally disposed steam ejector that impels feed materials from a feeder and solids from a recycle loop along with a motive gas into a top part of said reactor. 12 figs.

  14. The Holographic Superconductor Vortex

    E-Print Network [OSTI]

    Marc Montull; Alex Pomarol; Pedro J. Silva

    2009-09-02T23:59:59.000Z

    A gravity dual of a superconductor at finite temperature has been recently proposed. We present the vortex configuration of this model and study its properties. In particular, we calculate the free energy as a function of an external magnetic field, the magnetization and the superconducting density. We also find the two critical magnetic fields that define the region in which the vortex configurations are energetically favorable.

  15. Feasibility of a vortex transistor

    SciTech Connect (OSTI)

    Nevirkovets, I.P.; Rudenko, E.M.

    1985-08-01T23:59:59.000Z

    An experimental test is reported of the feasibility of developing a vortex transistor using tunnel junctions made from tin. (AIP)

  16. Multiple tube premixing device

    DOE Patents [OSTI]

    Uhm, Jong Ho; Naidu, Balachandar; Ziminksy, Willy Steve; Kraemer, Gilbert Otto; Yilmaz, Ertan; Lacy, Benjamin; Stevenson, Christian; Felling, David

    2013-08-13T23:59:59.000Z

    The present application provides a premixer for a combustor. The premixer may include a fuel plenum with a number of fuel tubes and a burner tube with a number of air tubes. The fuel tubes extend about the air tubes.

  17. Multiple tube premixing device

    DOE Patents [OSTI]

    Uhm, Jong Ho; Varatharajan, Balachandar; Ziminsky, Willy Steve; Kraemer, Gilbert Otto; Yilmaz, Ertan; Lacy, Benjamin; Stevenson, Christian; Felling, David

    2012-12-11T23:59:59.000Z

    The present application provides a premixer for a combustor. The premixer may include a fuel plenum with a number of fuel tubes and a burner tube with a number of air tubes. The fuel tubes extend about the air tubes.

  18. Vortex-Based Aero- and Hydrodynamic Estimation

    E-Print Network [OSTI]

    Hemati, Maziar Sam

    2013-01-01T23:59:59.000Z

    2001. [Kra91] R. Krasny. “Vortex Sheet Computations: Roll-NK94] M. Nitsche and R. Krasny. “A Numerical Study of Vortex

  19. Neutron tubes

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Lou, Tak Pui (Berkeley, CA); Reijonen, Jani (Oakland, CA)

    2008-03-11T23:59:59.000Z

    A neutron tube or generator is based on a RF driven plasma ion source having a quartz or other chamber surrounded by an external RF antenna. A deuterium or mixed deuterium/tritium (or even just a tritium) plasma is generated in the chamber and D or D/T (or T) ions are extracted from the plasma. A neutron generating target is positioned so that the ion beam is incident thereon and loads the target. Incident ions cause D-D or D-T (or T-T) reactions which generate neutrons. Various embodiments differ primarily in size of the chamber and position and shape of the neutron generating target. Some neutron generators are small enough for implantation in the body. The target may be at the end of a catheter-like drift tube. The target may have a tapered or conical surface to increase target surface area.

  20. VORTEX BREAKDOWN INCIPIENCE: THEORETICAL CONSIDERATIONS

    E-Print Network [OSTI]

    Erlebacher, Gordon

    ­dimensional boundary layer (Hall 2;3 , Mager 4 ); (ii) vortex breakdown is a consequence of hydrodynamic instabilityVORTEX BREAKDOWN INCIPIENCE: THEORETICAL CONSIDERATIONS S. A. Berger Department of Mechanical in Science and Engineering NASA Langley Research Center Hampton, VA 23681­0001 ABSTRACT The sensitivity

  1. Variable residence time vortex combustor

    DOE Patents [OSTI]

    Melconian, Jerry O. (76 Beaver Rd., Reading, MA 01867)

    1987-01-01T23:59:59.000Z

    A variable residence time vortex combustor including a primary combustion chamber for containing a combustion vortex, and a plurality of louvres peripherally disposed about the primary combustion chamber and longitudinally distributed along its primary axis. The louvres are inclined to impel air about the primary combustion chamber to cool its interior surfaces and to impel air inwardly to assist in driving the combustion vortex in a first rotational direction and to feed combustion in the primary combustion chamber. The vortex combustor also includes a second combustion chamber having a secondary zone and a narrowed waist region in the primary combustion chamber interconnecting the output of the primary combustion chamber with the secondary zone for passing only lower density particles and trapping higher density particles in the combustion vortex in the primary combustion chamber for substantial combustion.

  2. Fluidized bed boiler convective zone tube replacement

    SciTech Connect (OSTI)

    Not Available

    1991-03-21T23:59:59.000Z

    A major problem with the Georgetown University Atomspheric-Pressure, Fluidized-Bed Combustor-Boiler (GU AFBC) experienced during the first six years of operation was tube erosion. Previous corrective measures for in-bed tube erosion appeared to be effective, but excessive wear of the convective zone tubes was still occurring, and the entire heat transfer tube bundle in the boiler required replacement. In the planned project,the eroded tubes would be replaced, and the convective zone modified to eliminate the problem. Progress is discussed.

  3. All-optical discrete vortex switch

    SciTech Connect (OSTI)

    Desyatnikov, Anton S. [Nonlinear Physics Center, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia); Dennis, Mark R. [H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Ferrando, Albert [Interdisciplinary Modeling Group, InterTech and Departament d'Optica, Universitat de Valencia, E-46100 Burjassot (Spain)

    2011-06-15T23:59:59.000Z

    We introduce discrete vortex solitons and vortex breathers in circular arrays of nonlinear waveguides. The simplest vortex breather in a four-waveguide coupler is a nonlinear dynamic state changing its topological charge between +1 and -1 periodically during propagation. We find the stability domain for this solution and suggest an all-optical vortex switching scheme.

  4. Tube furnace

    DOE Patents [OSTI]

    Foster, Kenneth G. (Livermore, CA); Frohwein, Eugene J. (San Ramon, CA); Taylor, Robert W. (Livermore, CA); Bowen, David W. (Livermore, CA)

    1991-01-01T23:59:59.000Z

    A vermiculite insulated tube furnace is heated by a helically-wound resistance wire positioned within a helical groove on the surface of a ceramic cylinder, that in turn is surroundingly disposed about a doubly slotted stainless steel cylindrical liner. For uniform heating, the pitch of the helix is of shorter length over the two end portions of the ceramic cylinder. The furnace is of large volume, provides uniform temperature, offers an extremely precise programmed heating capability, features very rapid cool-down, and has a modest electrical power requirement.

  5. Tapered pulse tube for pulse tube refrigerators

    DOE Patents [OSTI]

    Swift, Gregory W. (Sante Fe, NM); Olson, Jeffrey R. (San Mateo, CA)

    1999-01-01T23:59:59.000Z

    Thermal insulation of the pulse tube in a pulse-tube refrigerator is maintained by optimally varying the radius of the pulse tube to suppress convective heat loss from mass flux streaming in the pulse tube. A simple cone with an optimum taper angle will often provide sufficient improvement. Alternatively, the pulse tube radius r as a function of axial position x can be shaped with r(x) such that streaming is optimally suppressed at each x.

  6. Tube-in-tube thermophotovoltaic generator

    DOE Patents [OSTI]

    Ashcroft, J.; Campbell, B.; DePoy, D.

    1998-06-30T23:59:59.000Z

    A thermophotovoltaic device includes at least one thermal radiator tube, a cooling tube concentrically disposed within each thermal radiator tube and an array of thermophotovoltaic cells disposed on the exterior surface of the cooling tube. A shell having a first end and a second end surrounds the thermal radiator tube. Inner and outer tubesheets, each having an aperture corresponding to each cooling tube, are located at each end of the shell. The thermal radiator tube extends within the shell between the inner tubesheets. The cooling tube extends within the shell through the corresponding apertures of the two inner tubesheets to the corresponding apertures of the two outer tubesheets. A plurality of the thermal radiator tubes can be arranged in a staggered or an in-line configuration within the shell. 8 figs.

  7. A tube-in-tube thermophotovoltaic generator

    SciTech Connect (OSTI)

    Ashcroft, J.; Campbell, B.; Depoy, D.

    1996-12-31T23:59:59.000Z

    A thermophotovoltaic device includes at least one thermal radiator tube, a cooling tube concentrically disposed within each thermal radiator tube and an array of thermophotovoltaic cells disposed on the exterior surface of the cooling tube. A shell having a first end and a second end surrounds the thermal radiator tube. Inner and outer tubesheets, each having an aperture corresponding to each cooling tube, are located at each end of the shell. The thermal radiator tube extends within the shell between the inner tubesheets. The cooling tube extends within the shell through the corresponding apertures of the two inner tubesheets to the corresponding apertures of the two outer tubesheets. A plurality of the thermal radiator tubes can be arranged in a staggered or an in-line configuration within the shell.

  8. Gravity waves from vortex dipoles and jets

    E-Print Network [OSTI]

    Wang, Shuguang

    2009-05-15T23:59:59.000Z

    The dissertation first investigates gravity wave generation and propagation from jets within idealized vortex dipoles using a nonhydrostatic mesoscale model. Several initially balanced and localized jets induced by vortex dipoles are examined here...

  9. Reduction of vortex induced forces and motion through surface roughness control

    DOE Patents [OSTI]

    Bernitsas, Michael M; Raghavan, Kamaldev

    2014-04-01T23:59:59.000Z

    Roughness is added to the surface of a bluff body in a relative motion with respect to a fluid. The amount, size, and distribution of roughness on the body surface is controlled passively or actively to modify the flow around the body and subsequently the Vortex Induced Forces and Motion (VIFM). The added roughness, when designed and implemented appropriately, affects in a predetermined way the boundary layer, the separation of the boundary layer, the level of turbulence, the wake, the drag and lift forces, and consequently the Vortex Induced Motion (VIM), and the fluid-structure interaction. The goal of surface roughness control is to decrease/suppress Vortex Induced Forces and Motion. Suppression is required when fluid-structure interaction becomes destructive as in VIM of flexible cylinders or rigid cylinders on elastic support, such as underwater pipelines, marine risers, tubes in heat exchangers, nuclear fuel rods, cooling towers, SPAR offshore platforms.

  10. A Flexural Mode Tuning Technique for Membraned Boiler Tubing

    SciTech Connect (OSTI)

    Quarry, M J; Chinn, D J; Rose, J L

    2005-03-21T23:59:59.000Z

    Corrosion of tubing used in black-liquor recovery boilers is a major concern in all pulp and paper mills. Extensive corrosion in recovery boiler tubes can result in a significant safety and environmental hazard. Considerable plant resources are expended to inspect recovery boiler tubing. Currently, visual and ultrasonic inspections are primarily used during the annual maintenance shutdown to monitor corrosion rates and cracking of tubing. This project is developing guided acoustic waves for use on recovery boiler tubing. The feature of this acoustic technique is its cost-effectiveness in inspecting long lengths of tubes from a single inspection point. A piezoelectric or electromagnetic transducer induces guided waves into the tubes. The transducer detects fireside defects from the cold side or fireside of the tube. Cracking and thinning on recovery boiler tubes have been detected with this technique in both laboratory and field applications.

  11. Microhole Tubing Bending Report

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Oglesby, Ken

    A downhole tubing bending study was made and is reported herein. IT contains a report and 2 excel spreadsheets to calculate tubing bending and to estimate contact points of the tubing to the drilled hole wall (creating a new support point).

  12. Microhole Tubing Bending Report

    SciTech Connect (OSTI)

    Oglesby, Ken

    2012-01-01T23:59:59.000Z

    A downhole tubing bending study was made and is reported herein. IT contains a report and 2 excel spreadsheets to calculate tubing bending and to estimate contact points of the tubing to the drilled hole wall (creating a new support point).

  13. Energy Spectrum of Vortex Tangle

    E-Print Network [OSTI]

    Tsunehiko Araki; Makoto Tsubota; Sergey K. Nemirovskii

    2001-06-29T23:59:59.000Z

    The energy spectrum of superfluid turbulence in the absence of the normal fluid is studied numerically. In order to discuss the statistical properties, we calculated the energy spectra of the 3D velocity field induced by dilute and dense vortex tangles respectively, whose dynamics is calculated by the Biot-Savart law. In the case of a dense tangle, the slope of the energy spectrum is changed at $k=2\\pi/l$, where $l$ is the intervortex spacing. For $k>2\\pi/l$, the energy spectrum has $k^{-1}$ behavior in the same manner as the dilute vortex tangle, while otherwise the slope of the energy spectrum deviates from $k^{-1}$ behavior. We compare the behavior for $k<2\\pi/l$ with the Kolmogorov law.

  14. Divergence of optical vortex beams

    E-Print Network [OSTI]

    Reddy, Salla Gangi; Prabhakar, Shashi; Anwar, Ali; Banerji, J; Singh, R P

    2015-01-01T23:59:59.000Z

    We show, both theoretically and experimentally, that the propagation of optical vortices in free space can be analysed by using the width ($w(z)$) of the host Gaussian beam and the inner and outer radii of the vortex beam at the source plane ($z=0$) as defined in \\textit{Optics Letters \\textbf{39,} 4364-4367 (2014)}. We also studied the divergence of vortex beams, considered as the rate of change of inner or outer radius with the propagation distance, and found that it varies with the order in the same way as that of the inner and outer radii at zero propagation distance. These results may be useful in designing optical fibers for orbital angular momentum modes that play a crucial role in quantum communication.

  15. Computing Vortex Sheet Motion Robert Krasny

    E-Print Network [OSTI]

    Krasny, Robert

    Computing Vortex Sheet Motion Robert Krasny Department of Mathematics, University of Michigan, Ann;1574 Robert Krasny with respect to the time variable and obtained results consistent with Moore

  16. Superconducting vortex pinning with artificially prepared nanostructures

    E-Print Network [OSTI]

    Rosen, Yaniv Jacob

    K. Schuller, “Enhanced superconducting vortex pinning withat T/Tc = 0.99 of a superconducting Nb thin film on aof the triangles. The superconducting critical temperature

  17. aircraft vortex spacing: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    calculations and find that nontopological vortex solutions exist as well as Q-ball type solutions, but topological vortex solutions are not admitted. Inyong Cho; Youngone...

  18. Vortex Hydro Energy Develops Transformational Technology to Harness...

    Energy Savers [EERE]

    Vortex Hydro Energy Develops Transformational Technology to Harness Energy from Water Currents Vortex Hydro Energy Develops Transformational Technology to Harness Energy from Water...

  19. Light propagation around a relativistic vortex flow of dielectric medium

    E-Print Network [OSTI]

    B. Linet

    2000-11-06T23:59:59.000Z

    We determine the path of the light around a dielectric vortex described by the relativistic vortex flow of a perfect fluid.

  20. advanced vortex element: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    method with mesh adaptivity for computing vortex states in fastrotating BoseEinstein condensates Computer Technologies and Information Sciences Websites Summary: ) vortices, vortex...

  1. accelerated vortex ring: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rings and systems for controlled studies of vortex interactions in Bose-Einstein condensates HEP - Theory (arXiv) Summary: We study controlled methods of preparing vortex...

  2. Vortex dynamics in 4 Banavara N. Shashikanth

    E-Print Network [OSTI]

    Shashikanth, Banavara N.

    Vortex dynamics in 4 Banavara N. Shashikanth Citation: J. Math. Phys. 53, 013103 (2012); doi: 10 OF MATHEMATICAL PHYSICS 53, 013103 (2012) Vortex dynamics in R4 Banavara N. Shashikantha) Mechanical and Aerospace dynamics of Euler's equations for a constant density fluid flow in R4 is studied. Most of the paper focuses

  3. An investigation of the vortex method

    SciTech Connect (OSTI)

    Pryor, D.W. Jr.

    1994-05-01T23:59:59.000Z

    The vortex method is a numerical scheme for solving the vorticity transport equation. Chorin introduced modern vortex methods. The vortex method is a Lagrangian, grid free method which has less intrinsic diffusion than many grid schemes. It is adaptive in the sense that elements are needed only where the vorticity is non-zero. Our description of vortex methods begins with the point vortex method of Rosenhead for two dimensional inviscid flow, and builds upon it to eventually cover the case of three dimensional slightly viscous flow with boundaries. This section gives an introduction to the fundamentals of the vortex method. This is done in order to give a basic impression of the previous work and its line of development, as well as develop some notation and concepts which will be used later. The purpose here is not to give a full review of vortex methods or the contributions made by all the researchers in the field. Please refer to the excellent review papers in Sethian and Gustafson, chapters 1 Sethian, 2 Hald, 3 Sethian, 8 Chorin provide a solid introduction to vortex methods, including convergence theory, application in two dimensions and connection to statistical mechanics and polymers. Much of the information in this review is taken from those chapters, Chorin and Marsden and Batchelor, the chapters are also useful for their extensive bibliographies.

  4. Vortex rings impinging on permeable boundaries

    E-Print Network [OSTI]

    Mujal-Colilles, Anna; Dalziel, Stuart B.; Bateman, Allen

    2015-01-17T23:59:59.000Z

    , and the existence of a rebound of the core parallel to the formation of a secondary 47 vortex with opposite sign [14]. 48 More recently, attention has turned to the possibility of resuspension due to a vortex ring 49 impacting a bed of particles (e.g. [1], [15...

  5. Conduction cooled tube supports

    DOE Patents [OSTI]

    Worley, Arthur C. (Mt. Tabor, NJ); Becht, IV, Charles (Morristown, NJ)

    1984-01-01T23:59:59.000Z

    In boilers, process tubes are suspended by means of support studs that are in thermal contact with and attached to the metal roof casing of the boiler and the upper bend portions of the process tubes. The support studs are sufficiently short that when the boiler is in use, the support studs are cooled by conduction of heat to the process tubes and the roof casing thereby maintaining the temperature of the stud so that it does not exceed 1400.degree. F.

  6. Coiled Tubing Safety Manual

    SciTech Connect (OSTI)

    Crow, W.

    1999-04-06T23:59:59.000Z

    This document addresses safety concerns regarding the use of coiled tubing as it pertains to the preservation of personnel, environment and the wellbore.

  7. Ergoregion instability: The hydrodynamic vortex

    E-Print Network [OSTI]

    Leandro A. Oliveira; Vitor Cardoso; Luís C. B. Crispino

    2014-05-16T23:59:59.000Z

    Four-dimensional, asymptotically flat spacetimes with an ergoregion but no horizon have been shown to be linearly unstable against a superradiant-triggered mechanism. This result has wide implications in the search for astrophysically viable alternatives to black holes, but also in the understanding of black holes and Hawking evaporation. Here we investigate this instability in detail for a particular setup which can be realized in the laboratory: the {\\it hydrodynamic vortex}, an effective geometry for sound waves, with ergoregion and without an event horizon.

  8. The idea of vortex energy

    E-Print Network [OSTI]

    V. E. Shapiro

    2011-09-22T23:59:59.000Z

    This work formulates and gives grounds for general principles and theorems that question the energy function doctrine and its quantum version as a genuine law of nature without borders of adequacy. The emphasis is on the domain where the energy of systems is conserved -- I argue that only in its tiny part the energy is in the kinetic, potential and thermal forms describable by a generalized thermodynamic potential, whereas otherwise the conserved energy constitutes a whole linked to vortex forces, and can be a factor of things like persistent currents and dark matter.

  9. Vortex Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlin BaxinUmweltVillageGraph Home Wzeng'sVortex Energy Jump to:

  10. Steam generator tube failures

    SciTech Connect (OSTI)

    MacDonald, P.E.; Shah, V.N.; Ward, L.W.; Ellison, P.G.

    1996-04-01T23:59:59.000Z

    A review and summary of the available information on steam generator tubing failures and the impact of these failures on plant safety is presented. The following topics are covered: pressurized water reactor (PWR), Canadian deuterium uranium (CANDU) reactor, and Russian water moderated, water cooled energy reactor (VVER) steam generator degradation, PWR steam generator tube ruptures, the thermal-hydraulic response of a PWR plant with a faulted steam generator, the risk significance of steam generator tube rupture accidents, tubing inspection requirements and fitness-for-service criteria in various countries, and defect detection reliability and sizing accuracy. A significant number of steam generator tubes are defective and are removed from service or repaired each year. This wide spread damage has been caused by many diverse degradation mechanisms, some of which are difficult to detect and predict. In addition, spontaneous tube ruptures have occurred at the rate of about one every 2 years over the last 20 years, and incipient tube ruptures (tube failures usually identified with leak detection monitors just before rupture) have been occurring at the rate of about one per year. These ruptures have caused complex plant transients which have not always been easy for the reactor operators to control. Our analysis shows that if more than 15 tubes rupture during a main steam line break, the system response could lead to core melting. Although spontaneous and induced steam generator tube ruptures are small contributors to the total core damage frequency calculated in probabilistic risk assessments, they are risk significant because the radionuclides are likely to bypass the reactor containment building. The frequency of steam generator tube ruptures can be significantly reduced through appropriate and timely inspections and repairs or removal from service.

  11. Vortex pinning by inhomogeneities in type-II superconductors

    E-Print Network [OSTI]

    Chapman, Jon

    Vortex pinning by inhomogeneities in type-II superconductors S.J. Chapman #3;y G. Richardson zx of a curvilinear vortex in an inhomogeneous type-II superconducting material in the limit as the vortex core radius of the superconducting electrons acts as a pinning potential for the vortex, so that vortices will be attracted

  12. Spatiotemporal characterization of ultrashort optical vortex pulses

    E-Print Network [OSTI]

    Miranda, Miguel; Rudawski, Piotr; Guo, Chen; Harth, Anne; L'Huillier, Anne; Arnold, Cord L

    2015-01-01T23:59:59.000Z

    Generation of few-cycle optical vortex pulses is challenging due to the large spectral bandwidths, as most vortex generation techniques are designed for monochromatic light. In this work, we use a spiral phase plate to generate few-cycle optical vortices from an ultrafast titanium:sapphire oscillator, and characterize them in the spatiotemporal domain using a recently introduced technique based on spatially resolved Fourier transform spectrometry. The performance of this simple approach to the generation of optical vortices is analyzed from a wavelength dependent perspective, as well as in the spatiotemporal domain, allowing us to completely characterize ultrashort vortex pulses in space, frequency, and time.

  13. Guided wave acoustic monitoring of corrosion in recovery boiler tubing

    SciTech Connect (OSTI)

    Quarry, M J; Chinn, D J

    2004-02-19T23:59:59.000Z

    Corrosion of tubing used in black-liquor recovery boilers is a major concern in all pulp and paper mills. Extensive corrosion in recovery boiler tubes can result in a significant safety and environmental hazard. Considerable plant resources are expended to inspect recovery boiler tubing. Currently, visual and ultrasonic inspections are primarily used during the annual maintenance shutdown to monitor corrosion rates and cracking of tubing. This Department of Energy, Office of Industrial Technologies project is developing guided acoustic waves for use on recovery boiler tubing. The feature of this acoustic technique is its cost-effectiveness in inspecting long lengths of tubes from a single inspection point. A piezoelectric or electromagnetic transducer induces guided waves into the tubes. The transducer detects fireside defects from the coldside or fireside of the tube. Cracking and thinning on recovery boiler tubes have been detected with this technique in both laboratory and field applications. This technique appears very promising for recovery boiler tube application, potentially expediting annual inspection of tube integrity.

  14. The Life of a Vortex Knot

    E-Print Network [OSTI]

    Kleckner, Dustin; Irvine, William T M

    2013-01-01T23:59:59.000Z

    The idea that the knottedness (hydrodynamic Helicity) of a fluid flow is conserved has a long history in fluid mechanics. The quintessential example of a knotted flow is a knotted vortex filament, however, owing to experimental difficulties, it has not been possible until recently to directly generate knotted vortices in real fluids. Using 3D printed hydrofoils and high-speed laser scanning tomography, we generate vortex knots and links and measure their subsequent evolution. In both cases, we find that the vortices deform and stretch until a series of vortex reconnections occurs, eventually resulting several disjoint vortex rings. This article accompanies a fluid dynamics video entered into the Gallery of Fluid Motion at the 66th Annual Meeting of the APS Division of Fluid Dynamics.

  15. Josephson vortex lattice in layered superconductors

    SciTech Connect (OSTI)

    Koshelev, A. E., E-mail: koshelev@anl.gov [Argonne National Laboratory, Materials Science Division (United States); Dodgson, M. J. W. [Cavendish Laboratory, Theory of Condensed Matter Group (United Kingdom)] [Cavendish Laboratory, Theory of Condensed Matter Group (United Kingdom)

    2013-09-15T23:59:59.000Z

    Many superconducting materials are composed of weakly coupled conducting layers. Such a layered structure has a very strong influence on the properties of vortex matter in a magnetic field. This review focuses on the properties of the Josephson vortex lattice generated by the magnetic field applied in the direction of the layers. The theoretical description is based on the Lawrence-Doniach model in the London limit, which takes only the phase degree of freedom of the superconducting order parameter into account. In spite of its simplicity, this model leads to an amazingly rich set of phenomena. We review in detail the structure of an isolated vortex line and various properties of the vortex lattice, in both dilute and dense limits. In particular, we extensively discuss the influence of the layered structure and thermal fluctuations on the selection of lattice configurations at different magnetic fields.

  16. The multiple vortex nature of tropical cyclogenesis

    E-Print Network [OSTI]

    Sippel, Jason Allen

    2005-02-17T23:59:59.000Z

    cells and vortices are the respective source of PV production and building blocks for the meso-?-scale vortices. Finally, this thesis discusses issues related to the multiple vortex nature of tropical cyclone formation. For instance, the tracking...

  17. Direct Imaging of Antiferromagnetic Vortex States

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    H.W. Zhao, J. Bokor, and Z.Q. Qiu, "Direct observation of imprinted antiferromagnetic vortex states in CoOFeAg(001) discs," Nat. Phys. 7, 303 (2011). ALS Science Highlight 235...

  18. Direct Imaging of Antiferromagnetic Vortex States

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and Z.Q. Qiu, "Direct observation of imprinted antiferromagnetic vortex states in CoOFeAg(001) discs," Nat. Phys. 7, 303 (2011). ALS Science Highlight 235 ALSNews Vol. 324...

  19. Phases of Atom-Molecule Vortex Matter

    SciTech Connect (OSTI)

    Woo, S. J.; Bigelow, N. P. [Department of Physics and Astronomy, University of Rochester, Rochester, New York (United States); Park, Q-Han [Department of Physics, Korea University, Seoul (Korea, Republic of)

    2008-03-28T23:59:59.000Z

    We study ground state vortex configurations in a rotating atom-molecule Bose-Einstein condensate. It is found that the coherent coupling between the atomic and molecular condensates can render a pairing of atomic and molecular vortices into a composite structure that resembles a carbon dioxide molecule. Structural phase transitions of vortex lattices are also explored through different physical parameters including the rotational frequency of the system.

  20. Effects of Combustion-Induced Vortex Breakdown on Flashback Limits of Syngas-Fueled Gas Turbine Combustors

    SciTech Connect (OSTI)

    Ahsan Choudhuri

    2011-03-31T23:59:59.000Z

    Turbine combustors of advanced power systems have goals to achieve very low pollutants emissions, fuel variability, and fuel flexibility. Future generation gas turbine combustors should tolerate fuel compositions ranging from natural gas to a broad range of syngas without sacrificing operational advantages and low emission characteristics. Additionally, current designs of advanced turbine combustors use various degrees of swirl and lean premixing for stabilizing flames and controlling high temperature NOx formation zones. However, issues of fuel variability and NOx control through premixing also bring a number of concerns, especially combustor flashback and flame blowout. Flashback is a combustion condition at which the flame propagates upstream against the gas stream into the burner tube. Flashback is a critical issue for premixed combustor designs, because it not only causes serious hardware damages but also increases pollutant emissions. In swirl stabilized lean premixed turbine combustors onset of flashback may occur due to (i) boundary layer flame propagation (critical velocity gradient), (ii) turbulent flame propagation in core flow, (iii) combustion instabilities, and (iv) upstream flame propagation induced by combustion induced vortex breakdown (CIVB). Flashback due to first two foregoing mechanisms is a topic of classical interest and has been studied extensively. Generally, analytical theories and experimental determinations of laminar and turbulent burning velocities model these mechanisms with sufficient precision for design usages. However, the swirling flow complicates the flashback processes in premixed combustions and the first two mechanisms inadequately describe the flashback propensity of most practical combustor designs. The presence of hydrogen in syngas significantly increases the potential for flashback. Due to high laminar burning velocity and low lean flammability limit, hydrogen tends to shift the combustor operating conditions towards flashback regime. Even a small amount of hydrogen in a fuel blend triggers the onset of flashback by altering the kinetics and thermophysical characteristics of the mixture. Additionally, the presence of hydrogen in the fuel mixture modifies the response of the flame to the global effects of stretch and preferential diffusion. Despite its immense importance in fuel flexible combustor design, little is known about the magnitude of fuel effects on CIVB induced flashback mechanism. Hence, this project investigates the effects of syngas compositions on flashback resulting from combustion induced vortex breakdown. The project uses controlled experiments and parametric modeling to understand the velocity field and flame interaction leading to CIVB driven flashback.

  1. Vortex Hydro Energy (TRL 5 6 System) - Advanced Integration of...

    Broader source: Energy.gov (indexed) [DOE]

    Vortex Hydro Energy (TRL 5 6 System) - Advanced Integration of Power Take-Off in VIVACE Vortex Hydro Energy (TRL 5 6 System) - Advanced Integration of Power Take-Off in VIVACE...

  2. Stress-Assisted Corrosion in Boiler Tubes

    SciTech Connect (OSTI)

    Preet M Singh; Steven J Pawel

    2006-05-27T23:59:59.000Z

    A number of industrial boilers, including in the pulp and paper industry, needed to replace their lower furnace tubes or decommission many recovery boilers due to stress-assisted corrosion (SAC) on the waterside of boiler tubes. More than half of the power and recovery boilers that have been inspected reveal SAC damage, which portends significant energy and economic impacts. The goal of this project was to clarify the mechanism of stress-assisted corrosion (SAC) of boiler tubes for the purpose of determining key parameters in its mitigation and control. To accomplish this in-situ strain measurements on boiler tubes were made. Boiler water environment was simulated in the laboratory and effects of water chemistry on SAC initiation and growth were evaluated in terms of industrial operations. Results from this project have shown that the dissolved oxygen is single most important factor in SAC initiation on carbon steel samples. Control of dissolved oxygen can be used to mitigate SAC in industrial boilers. Results have also shown that sharp corrosion fatigue and bulbous SAC cracks have similar mechanism but the morphology is different due to availability of oxygen during boiler shutdown conditions. Results are described in the final technical report.

  3. Erosion of heat exchanger tubes in fluidized beds

    SciTech Connect (OSTI)

    Johnson, E.K.; Flemmer, R.L.C.

    1991-01-01T23:59:59.000Z

    This final report describes the activities of the 3-year project entitled Erosion of Heat Exchanger Tubes In Fluidized Beds.'' which was completed at the end of 1990. Project accomplishments include the collection of a substantial body of wear data In a 24in. [times] 24in. fluidized bed, comparative wear results In a 6in. [times] 6in. fluidized bed, the development of a dragometer and the collection of a comprehensive set of drag force data in the 24in. [times] 24in. bed, Fast Fourier Transform (FFT) analysis of bubble probe data to establish dominant bubble frequencies in the 24in. [times] 24in. bed, the use of a heat flux gauge for measurement of heat transfer coefficients in the 24in. [times] 24in. bed and the modeling of the tube wear in the 24in. [times] 24in. bed. Analysis of the wear data from the 24in. square bed indicates that tube wear increases with increase in superficial velocity, and with increase in tube height. The latter effect is a result of the tubes higher up in the bed seeing greater movement of dense phase than tubes lower down In the bed. In addition, tube wear was found to decrease with increase in particle size, for constant superficial velocity. Three models of tube wear were formulated and provided acceptable prediction of wear when compared with the experimental data.

  4. Fractal powers in Serrin's swirling vortex solutions

    E-Print Network [OSTI]

    Pavel B?lík; Douglas P. Dokken; Kurt Scholz; Mikhail M. Shvartsman

    2014-04-28T23:59:59.000Z

    We consider a modification of the fluid flow model for a tornado-like swirling vortex developed by J. Serrin, where velocity decreases as the reciprocal of the distance from the vortex axis. Recent studies, based on radar data of selected severe weather events, indicate that the angular momentum in a tornado may not be constant with the radius, and thus suggest a different scaling of the velocity/radial distance dependence. Motivated by this suggestion, we consider Serrin's approach with the assumption that the velocity decreases as the reciprocal of the distance from the vortex axis to the power $b$ with a general $b>0$. This leads to a boundary-value problem for a system of nonlinear differential equations. We analyze this problem for particular cases, both with nonzero and zero viscosity, discuss the question of existence of solutions, and use numerical techniques to describe those solutions that we cannot obtain analytically.

  5. Texas Stream Team Special Projects

    E-Print Network [OSTI]

    Texas Stream Team Special Projects · TMDL and Watershed Protection Plan Projects · Steering ­ Transparency tube ­ E. coli · Web site resources · Materials ­ Maps, Watershed Models Orange County Adams training sessions · Quality control · NPS education sessions · Volunteers of the month · Orange county

  6. Removing the concavity of the thick center vortex potentials by fluctuating the vortex profile

    E-Print Network [OSTI]

    Sedigheh Deldar; Shahnoosh Rafibakhsh

    2010-03-14T23:59:59.000Z

    The thick center vortex model reproduces important aspects of the potentials between static quark sources as seen in lattice Yang-Mills calculations: Both the intermediate distance behavior, governed by Casimir scaling, as well as the long distance behavior, governed by N-ality, are obtained. However, when a fixed vortex profile is used, these two distance regimes do not connect naturally to each other. The transition in general violates concavity constraints on the potential, especially for higher representations of the gauge group. We demonstrate how this issue can be alleviated when the vortex profile is allowed to fluctuate within this simple model.

  7. Fluorescent Tube Lamps

    Broader source: Energy.gov [DOE]

    FEMP temporarily suspended its energy efficiency requirements for fluorescent tube lamps as it evaluates the market impact of the pending 2012 minimum efficiency standards for fluorescent lamps. The program will issue updated energy efficiency requirements when the market distribution of this product category stabilizes and when doing so has the potential to result in significant Federal energy savings.

  8. Shock Tube Design

    E-Print Network [OSTI]

    Koppenberger, Peter K.

    2010-07-14T23:59:59.000Z

    , and provide two driver sections to allow for dual shock capability. The tube was designed to accommodate a 2.5 MACH shockwave, and incorporated a factor of safety of 3 in the design. A modular approach to design was followed to allow further diversification...

  9. Acoustics of finite-aperture vortex beams

    E-Print Network [OSTI]

    Mitri, F G

    2014-01-01T23:59:59.000Z

    A method based on the Rayleigh-Sommerfeld surface integral is provided, which makes it feasible to rigorously model, evaluate and compute the acoustic scattering and other mechanical effects of finite-aperture vortex beams such as the acoustic radiation force and torque on a viscoelastic sphere in various applications in acoustic tweezers and microfluidics, particle entrapment, manipulation and rotation. Partial-wave series expansions are derived for the incident field of acoustic spiraling (vortex) beams, comprising high-order Bessel and Bessel-Gauss beams.

  10. Invariants for Tendex and Vortex Fields

    E-Print Network [OSTI]

    Kenneth A. Dennison; Thomas W. Baumgarte

    2012-08-06T23:59:59.000Z

    Tendex and vortex fields, defined by the eigenvectors and eigenvalues of the electric and magnetic parts of the Weyl curvature tensor, form the basis of a recently developed approach to visualizing spacetime curvature. In analogy to electric and magnetic fields, these fields are coordinate-dependent. However, in a further analogy, we can form invariants from the tendex and vortex fields that are invariant under coordinate transformations, just as certain combinations of the electric and magnetic fields are invariant under coordinate transformations. We derive these invariants, and provide a simple, analytical demonstration for non-spherically symmetric slices of a Schwarzschild spacetime.

  11. Forebay Computational Fluid Dynamics Modeling for The Dalles Dam to Support Vortex Suppress Device Studies

    SciTech Connect (OSTI)

    Rakowski, Cynthia L.; Richmond, Marshall C.; Serkowski, John A.

    2006-12-01T23:59:59.000Z

    A computational fluid dynamics (CFD) model was used in an investigation into the suppression of a surface vortex that forms and the south-most spilling bay at The Dalles Project. The CFD work complemented work at the prototype and the reduced-scale physical models. The CFD model was based on a model developed for other work in the forebay but had additional resolution added near the spillway. Vortex suppression devices (VSDs) were to placed between pier noses and/or in the bulkhead slot of the spillway bays. The simulations in this study showed that placing VSD structures or a combination of structures to suppress the vortex would still result in near-surface flows to be entrained in a vortex near the downstream spillwall. These results were supported by physical model and prototype studies. However, there was a consensus of the fish biologists at the physical model that the fish would most likely move north and if the fish went under the VSD it would immediately exit the forebay through the tainter gate and not get trapped between VSDs or the VSDs and the tainter gate if the VSDs were deep enough.

  12. Spectral Techniques for Solving PDE Stability Model of Vortex Rope

    E-Print Network [OSTI]

    Bistrian, Diana Alina

    2012-01-01T23:59:59.000Z

    In this paper spectral methods are applied to investigate the hydrodynamic instability of swirling flow with application to Francis hydraulic turbine. Spectral methods imply representing the problem solution as truncated series of smooth global functions. An L2 - projection and the collocation methods are developed assessing both analytically methodology and computational techniques using symbolic and numerical conversions. Remarks concerning the efficiency and the accuracy of each method in this case are presented. The model of the trailing vortex is used to validate the numerical algorithms with existing results in the literature. All the results are compared to existing ones and they prove to agree quite well. The advantages of using this methods in flow control problems are pointed out.

  13. Induction plasma tube

    DOE Patents [OSTI]

    Hull, D.E.

    1982-07-02T23:59:59.000Z

    An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.

  14. Induction plasma tube

    DOE Patents [OSTI]

    Hull, Donald E. (Los Alamos, NM)

    1984-01-01T23:59:59.000Z

    An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.

  15. Convergenceof Vortex Methods for Weak Solutionsto the

    E-Print Network [OSTI]

    Liu, Jian-Guo

    , Krasny applied such a method in his calculations of the evolution of vortex sheetseven past the time when numerical simulations;see Krasny, [16] and [17], and Baker and Shelley, [l]. It is thus important to analyze by Krasny (see [16] and [17]). Our analysis is closely related to that of [9], [lo], and [18], and based

  16. Quenching Processes in Flame-Vortex Interactions

    E-Print Network [OSTI]

    Zingale, Michael

    for Astrophysical Thermonuclear Flashes 1 , Chicago, IL 60637 y Department of Astronomy and Astrophysics, University-vortex interactions in order to understand quenching of thermonuclear ames. The key question is|can a ther- monuclear. If a ame encounters a 1) The Center for Astrophysical Thermonuclear Flashes is supported by the Department

  17. Bifurcation to vortex solutions in superconducting lms

    E-Print Network [OSTI]

    Chapman, Jon

    Bifurcation to vortex solutions in superconducting #12;lms T. Boeck #3; S.J. Chapman y Mathematical state to a superconducting state in a decreasing magnetic #12;eld is studied for a slab geometry of these behaviours will occur in practice. 1 Introduction If a superconducting body is placed in a suÃ?ciently strong

  18. Joined concentric tubes

    DOE Patents [OSTI]

    DeJonghe, Lutgard; Jacobson, Craig; Tucker, Michael; Visco, Steven

    2013-01-01T23:59:59.000Z

    Tubular objects having two or more concentric layers that have different properties are joined to one another during their manufacture primarily by compressive and friction forces generated by shrinkage during sintering and possibly mechanical interlocking. It is not necessary for the concentric tubes to display adhesive-, chemical- or sinter-bonding to each other in order to achieve a strong bond. This facilitates joining of dissimilar materials, such as ceramics and metals.

  19. Photomultiplier Tube Testing

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for RenewableSpeedingBiomassPPPOPetroleum Reserves Vision,4 Photomultiplier Tube Testing

  20. Concentric tube support assembly

    SciTech Connect (OSTI)

    Rubio, Mark F.; Glessner, John C.

    2012-09-04T23:59:59.000Z

    An assembly (45) includes a plurality of separate pie-shaped segments (72) forming a disk (70) around a central region (48) for retaining a plurality of tubes (46) in a concentrically spaced apart configuration. Each segment includes a support member (94) radially extending along an upstream face (96) of the segment and a plurality of annularly curved support arms (98) transversely attached to the support member and radially spaced apart from one another away from the central region for receiving respective upstream end portions of the tubes in arc-shaped spaces (100) between the arms. Each segment also includes a radial passageway (102) formed in the support member for receiving a fluid segment portion (106) and a plurality of annular passageways (104) formed in the support arms for receiving respective arm portions (108) of the fluid segment portion from the radial passageway and for conducting the respective arm portions into corresponding annular spaces (47) formed between the tubes retained by the disk.

  1. Neutron Scattering Studies of Vortex Matter in Type-II Superconductors

    SciTech Connect (OSTI)

    Xinsheng Ling

    2012-02-02T23:59:59.000Z

    The proposed program is an experimental study of the fundamental properties of Abrikosov vortex matter in type-II superconductors. Most superconducting materials used in applications such as MRI are type II and their transport properties are determined by the interplay between random pinning, interaction and thermal fluctuation effects in the vortex state. Given the technological importance of these materials, a fundamental understanding of the vortex matter is necessary. The vortex lines in type-II superconductors also form a useful model system for fundamental studies of a number of important issues in condensed matter physics, such as the presence of a symmetry-breaking phase transition in the presence of random pinning. Recent advances in neutron scattering facilities such as the major upgrade of the NIST cold source and the Spallation Neutron Source are providing unprecedented opportunities in addressing some of the longstanding issues in vortex physics. The core component of the proposed program is to use small angle neutron scattering and Bitter decoration experiments to provide the most stringent test of the Bragg glass theory by measuring the structure factor in both the real and reciprocal spaces. The proposed experiments include a neutron reflectometry experiment to measure the precise Q-dependence of the structure factor of the vortex lattice in the Bragg glass state. A second set of SANS experiments will be on a shear-strained Nb single crystal for testing a recently proposed theory of the stability of Bragg glass. The objective is to artificially create a set of parallel grain boundaries into a Nb single crystal and use SANS to measure the vortex matter diffraction pattern as a function of the changing angle between the applied magnetic field to the grain boundaries. The intrinsic merits of the proposed work are a new fundamental understanding of type-II superconductors on which superconducting technology is based, and a firm understanding of phases and phase transitions in condensed matter systems with random pinning. The broader impact of the program includes the training of future generation of neutron scientists, and further development of neutron scattering and complementary techniques for studies of superconducting materials. The graduate and undergraduate students participating in this project will learn the state-of-the-art neutron scattering techniques, acquire a wide range of materials research experiences, and participate in the frontier research of superconductivity. This should best prepare the students for future careers in academia, industry, or government.

  2. Strings, vortex rings, and modes of instability

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gubser, Steven S.; Nayar, Revant; Parikh, Sarthak

    2015-03-01T23:59:59.000Z

    We treat string propagation and interaction in the presence of a background Neveu–Schwarz three-form field strength, suitable for describing vortex rings in a superfluid or low-viscosity normal fluid. A circular vortex ring exhibits instabilities which have been recognized for many years, but whose precise boundaries we determine for the first time analytically in the small core limit. Two circular vortices colliding head-on exhibit stronger instabilities which cause splitting into many small vortices at late times. We provide an approximate analytic treatment of these instabilities and show that the most unstable wavelength is parametrically larger than a dynamically generated length scalemore »which in many hydrodynamic systems is close to the cutoff. We also summarize how the string construction we discuss can be derived from the Gross–Pitaevskii Lagrangian, and also how it compares to the action for giant gravitons.« less

  3. Deterministic Josephson Vortex Ratchet with a load

    E-Print Network [OSTI]

    M. Knufinke; K. Ilin; M. Siegel; D. Koelle; R. Kleiner; E. Goldobin

    2011-09-29T23:59:59.000Z

    We investigate experimentally a deterministic underdamped Josephson vortex ratchet -- a fluxon-particle moving along a Josephson junction in an asymmetric periodic potential. By applying a sinusoidal driving current one can compel the vortex to move in a certain direction, producing average dc voltage across the junction. Being in such a rectification regime we also load the ratchet, i.e., apply an additional dc bias current I_dc (counterforce) which tilts the potential so that the fluxon climbs uphill due to the ratchet effect. The value of the bias current at which the fluxon stops climbing up defines the strength of the ratchet effect and is determined experimentally. This allows us to estimate the loading capability of the ratchet, the output power and efficiency. For the quasi-static regime we present a simple model which delivers simple analytic expressions for the above mentioned figures of merit.

  4. Vortex state in a doped Mott insulator M. Franz and Z. Tesanovic

    E-Print Network [OSTI]

    Tesanovic, Zlatko

    predicts two types of singly quantized vortices: an insulating ``holon'' vortex in the underdoped and a metallic ``spinon'' vortex in the overdoped region of the phase diagram. We argue that the holon vortex

  5. Multiple precision, multiple processor vortex sheet roll-up computation

    SciTech Connect (OSTI)

    Bailey, D.H. [NASA Ames Research Center, Moffett Field, CA (United States); Krasny, R. [Univ. of Michigan, Ann Arbor, MI (United States); Pelz, R. [Rutgers Univ., Piscataway, NJ (United States)

    1993-12-31T23:59:59.000Z

    A vortex sheet in incompressible flow is a surface across which the tangential fluid velocity has a jump discontinuity. A basic idea in fluid dynamics going back to Prandtl is that the vortex sheet can be obtained as the zero viscosity limit of a sequence of smooth solutions to the Navier-Stokes equations. Thus, the investigation of vortex sheet motion may yield insight into the structure of high Reynolds number flow.

  6. Optical vortex interaction and generation via nonlinear wave mixing

    SciTech Connect (OSTI)

    Lenzini, F. [INLN, Universite de Nice-Sophia Antipolis, CNRS, 1361 route des Lucioles, FR-06560 Valbonne (France); Dipartimento di Fisica, Universita di Firenze, via Sansone 1, IT-50019 Sesto Fiorentino (Italy); Residori, S.; Bortolozzo, U. [INLN, Universite de Nice-Sophia Antipolis, CNRS, 1361 route des Lucioles, FR-06560 Valbonne (France); Arecchi, F. T. [Dipartimento di Fisica, Universita di Firenze, via Sansone 1, IT-50019 Sesto Fiorentino (Italy)

    2011-12-15T23:59:59.000Z

    Optical vortex beams are made to interact via degenerate two-wave mixing in a Kerr-like nonlinear medium. Vortex mixing is shown to occur inside the medium, leading to exchange of topological charge and cascaded generation of vortex beams. A mean-field model is developed and is shown to account for the selection rules of the topological charges observed after the wave-mixing process. Fractional charges are demonstrated to follow the same rules as for integer charges.

  7. Laboratory Analysis of Vortex Dynamics For Shallow Tidal Inlets

    E-Print Network [OSTI]

    Whilden, Kerri Ann

    2010-10-12T23:59:59.000Z

    of the secondary structures into the vortex system are shown as well as variations in characteristics such as trajectory, size, vorticity, and circulation for the vortices as they move downstream. iv To the loved ones who have encouraged me along the way. v.... : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 30 13 Non-Dimensional Vorticity at the Swirl Strength Peak for the Pri- mary Vortex Within the Vortex System Versus Non-Dimensional Horizontal Location of the Centroid. : : : : : : : : : : : : : : : : : : 31 14 Non-Dimensional Circulation...

  8. Reduced-vibration tube array

    DOE Patents [OSTI]

    Bruck, Gerald J.; Bartolomeo, Daniel R.

    2004-07-20T23:59:59.000Z

    A reduced-vibration tube array is disclosed. The array includes a plurality of tubes in a fixed arrangement and a plurality of damping members positioned within the tubes. The damping members include contoured interface regions characterized by bracing points that selectively contact the inner surface of an associated tube. Each interface region is sized and shaped in accordance with the associated tube, so that the damping member bracing points are spaced apart a vibration-reducing distance from the associated tube inner surfaces at equilibrium. During operation, mechanical interaction between the bracing points and the tube inner surfaces reduces vibration by a damage-reducing degree. In one embodiment, the interface regions are serpentine shaped. In another embodiment, the interface regions are helical in shape. The interface regions may be simultaneously helical and serpentine in shape. The damping members may be fixed within the associated tubes, and damping member may be customized several interference regions having attributes chosen in accordance with desired flow characteristics and associated tube properties.

  9. VFLOW2D - A Vorte-Based Code for Computing Flow Over Elastically Supported Tubes and Tube Arrays

    SciTech Connect (OSTI)

    WOLFE,WALTER P.; STRICKLAND,JAMES H.; HOMICZ,GREGORY F.; GOSSLER,ALBERT A.

    2000-10-11T23:59:59.000Z

    A numerical flow model is developed to simulate two-dimensional fluid flow past immersed, elastically supported tube arrays. This work is motivated by the objective of predicting forces and motion associated with both deep-water drilling and production risers in the oil industry. This work has other engineering applications including simulation of flow past tubular heat exchangers or submarine-towed sensor arrays and the flow about parachute ribbons. In the present work, a vortex method is used for solving the unsteady flow field. This method demonstrates inherent advantages over more conventional grid-based computational fluid dynamics. The vortex method is non-iterative, does not require artificial viscosity for stability, displays minimal numerical diffusion, can easily treat moving boundaries, and allows a greatly reduced computational domain since vorticity occupies only a small fraction of the fluid volume. A gridless approach is used in the flow sufficiently distant from surfaces. A Lagrangian remap scheme is used near surfaces to calculate diffusion and convection of vorticity. A fast multipole technique is utilized for efficient calculation of velocity from the vorticity field. The ability of the method to correctly predict lift and drag forces on simple stationary geometries over a broad range of Reynolds numbers is presented.

  10. active vortex generators: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    how an initial dusturbing cyclonic vortex is created by collision between two linear wind jets under certain conditions, which under favorable conditions, may mature into a...

  11. Eddy sensors for small diameter stainless steel tubes.

    SciTech Connect (OSTI)

    Skinner, Jack L.; Morales, Alfredo Martin; Grant, J. Brian; Korellis, Henry James; LaFord, Marianne Elizabeth; Van Blarigan, Benjamin; Andersen, Lisa E.

    2011-08-01T23:59:59.000Z

    The goal of this project was to develop non-destructive, minimally disruptive eddy sensors to inspect small diameter stainless steel metal tubes. Modifications to Sandia's Emphasis/EIGER code allowed for the modeling of eddy current bobbin sensors near or around 1/8-inch outer diameter stainless steel tubing. Modeling results indicated that an eddy sensor based on a single axial coil could effectively detect changes in the inner diameter of a stainless steel tubing. Based on the modeling results, sensor coils capable of detecting small changes in the inner diameter of a stainless steel tube were designed, built and tested. The observed sensor response agreed with the results of the modeling and with eddy sensor theory. A separate limited distribution SAND report is being issued demonstrating the application of this sensor.

  12. Instability of Non-vortex State toward a Quantized Vortex in Bose-Einstein Condensate under External Rotation

    E-Print Network [OSTI]

    Tomoya Isoshima; Kazushige Machida

    1999-02-27T23:59:59.000Z

    The instability condition of the non-vortex state toward vortex formation is exa mined within the Bogoliubov theory when a Bose-Einstein condensate is under exte rnally forced rotation. The obtained critical angular velocity combined with the previous stability cond itions for a votex yields a detailed phase diagram in the critical velocity vs t he system parameter. This facilitates vortex formation experiments for alkali atom gases confined in a harmonic potential.

  13. SINGLE CRYSTAL NIOBIUM TUBES FOR PARTICLE COLLIDERS ACCELERATOR CAVITIES

    SciTech Connect (OSTI)

    MURPHY, JAMES E [University of Nevada, Reno] [University of Nevada, Reno

    2013-02-28T23:59:59.000Z

    The objective of this research project is to produce single crystal niobium (Nb) tubes for use as particle accelerator cavities for the Fermi laboratory’s International Linear Collider project. Single crystal Nb tubes may have superior performance compared to a polycrystalline tubes because the absence of grain boundaries may permit the use of higher accelerating voltages. In addition, Nb tubes that are subjected to the high temperature, high vacuum crystallization process are very pure and well annealed. Any impurity with a significantly higher vapor pressure than Nb should be decreased by the relatively long exposure at high temperature to the high vacuum environment. After application of the single crystal process, the surfaces of the Nb tubes are bright and shiny, and the tube resembles an electro polished Nb tube. For these reasons, there is interest in single crystal Nb tubes and in a process that will produce single crystal tubes. To convert a polycrystalline niobium tube into a single crystal, the tube is heated to within a few hundred ?C of the melting temperature of niobium, which is 2477 ?C. RF heating is used to rapidly heat the tube in a narrow zone and after reaching the operating temperature, the hot zone is slowly passed along the length of the tube. For crystallization tests with Nb tubes, the traverse rate was in the range of 1-10 cm per hour. All the crystallization tests in this study were performed in a water-cooled, stainless steel chamber under a vacuum of 5 x10-6 torr or better. In earliest tests of the single crystal growth process, the Nb tubes had an OD of 1.9 cm and a wall thickness of 0.15 mm. With these relatively small Nb tubes, the single crystal process was always successful in producing single crystal tubes. In these early tests, the operating temperature was normally maintained at 2200 ?C, and the traverse rate was 5 cm per hour. In the next test series, the Nb tube size was increased to 3.8 cm OD and the wall thickness was increased 0.18 mm and eventually to 0.21 mm. Again, with these larger tubes, single crystal tubes were usually produced by the crystallization process. The power supply was generally operated at full output during these tests, and the traverse rate was 5 cm per hour. In a few tests, the traverse rate was increased to 10 cm per hour, and at the faster traverse rate, single crystal growth was not achieved. In these tests with a faster traverse rate, it was thought that the tube was not heated to a high enough temperature to achieve single crystal growth. In the next series of tests, the tube OD was unchanged at 3.8 cm and the wall thickness was increased to 0.30 mm. The increased wall thickness made it difficult to reach an operating temperature above 2,000 ?C, and although the single crystal process caused a large increase in the crystal grains, no single crystal tubes were produced. It was assumed that the operating temperature in these tests was not high enough to achieve single crystal growth. In FY 2012, a larger power supply was purchased and installed. With the new power supply, temperatures above the melting point of Nb were easily obtained regardless of the tube thickness. A series of crystallization tests was initiated to determine if indeed the operating temperature of the previous tests was too low to achieve single crystal growth. For these tests, the Nb tube OD remained at 3.8 cm and the wall thickness was 0.30 mm. The first test had an operating temperature of 2,000 ?C. and the operating temperature was increased by 50 ?C increments for each successive test. The final test was very near the Nb melting temperature, and indeed, the Nb tube eventually melted in the center of the tube. These tests showed that higher temperatures did yield larger grain sizes if the traverse rate was held constant at 5 cm per hour, but no single crystal tubes were produced even at the highest operating temperature. In addition, slowing the traverse rate to as low as 1 cm per hour did not yield a single crystal tube regardless of operating temperature. At this time, it

  14. Tubing pressurized firing apparatus for a tubing conveyed perforating gun

    SciTech Connect (OSTI)

    Davies, D. L.

    1985-11-26T23:59:59.000Z

    A tubing pressurized firing apparatus is shown for use with a tubing conveyed perforating gun of the type used to perforate a cased well bore. The firing apparatus has a tubular body with an upper end for connection in the well tubing string and with a lower end for connection to a well perforating gun. An inner mandrel is slidably mounted within the tubular body and has a ball seat formed in the interior bore thereof for receiving a ball dropped through the well tubing string. The ball and ball seat together form a pressure tight seal whereby tubing pressure in the well tubing string acts on the inner mandrel to slide the mandrel downwardly within the tubular body. A cocking mechanism located below the inner mandrel within the body includes a lockout member which is initially positioned between a detonating pin and a percussion detonator. The cocking mechanism is actuated by downward sliding movement of the inner mandrel to move the lockout member from between the detonating pin and percussion detonator whereby a subsequent release of tubing pressure and upward sliding movement of the inner mandrel exposes the detonating pin to the percussion detonator to actuate the detonator and fire the perforating gun.

  15. Center Manifold Analysis of a PointVortex Model of Vortex Shedding with Control

    E-Print Network [OSTI]

    Protas, Bartosz

    of the point vortex F¨oppl system with linear feedback control. The F¨oppl system was used in an earlier system. Key words: point vortices, flow control, dynamical systems, wake flows PACS: 47.15.Hg, 47.27.Rc, 47.27.Vf 1 Introduction Integration of rigorous methods of Modern Control Theory with Computational

  16. Center Vortex vs. Abelian models of the QCD vacuum

    E-Print Network [OSTI]

    Höllwieser, Roman

    2015-01-01T23:59:59.000Z

    We present evidence that the center vortex model of confinement is more consistent with lattice results than other currently available models. In particular we show that Abelian field distributions predicted by monopole plasma, caloron gas or dual superconductor models cannot reproduce the area-law falloff of double winding Wilson loops in full $SU(2)$ and center vortex only gauge fields.

  17. Vortex Lattice Modelling of Winglets on Wind Turbine Blades

    E-Print Network [OSTI]

    Vortex Lattice Modelling of Winglets on Wind Turbine Blades Mads Døssing Risø-R-1621(EN) Risø Title: Vortex Lattice Modelling of Winglets on Wind Turbine Blades Departments: Wind Energy Department turbines can be increased by the use of winglets without increasing the swept area. This makes them

  18. Geometrical statistics and vortex structures in helical and nonhelical turbulences

    E-Print Network [OSTI]

    Li, Yi

    , United Kingdom Received 4 August 2009; accepted 20 January 2010; published online 9 March 2010 explained in terms of the self-induced motions of local vortex structures, which tend to wind up the vortex­11,13­15 the effects of helicity on energy cascade,16 the interaction between helicity and energy dissipation,17

  19. Flux tubes in the SU(3) vacuum: London penetration depth and coherence length

    E-Print Network [OSTI]

    Paolo Cea; Leonardo Cosmai; Francesca Cuteri; Alessandro Papa

    2014-04-04T23:59:59.000Z

    Within the dual superconductor scenario for the QCD confining vacuum, the chromoelectric field generated by a static $q\\overline{q}$ pair can be fitted by a function derived, by dual analogy, from a simple variational model for the magnitude of the normalized order parameter of an isolated Abrikosov vortex. Previous results for the SU(3) vacuum are revisited, but here the transverse chromoelectric field is measured by means of the connected correlator of two Polyakov loops and, in order to reduce noise, the smearing procedure is used instead of cooling. The penetration and coherence lengths of the flux tube are then extracted from the fit and compared with previous results.

  20. Final Report: Guided Acoustic Wave Monitoring of Corrosion in Recovery Boiler Tubing

    SciTech Connect (OSTI)

    Chinn, D J; Quarry, M J; Rose, J L

    2005-03-31T23:59:59.000Z

    Corrosion of tubing used in black-liquor recovery boilers is a major concern in all pulp and paper mills. Extensive corrosion in recovery boiler tubes can result in a significant safety and environmental hazard. Considerable plant resources are expended to inspect recovery boiler tubing. Currently, visual and ultrasonic inspections are primarily used during the annual maintenance shutdown to monitor corrosion rates and cracking of tubing. This Department of Energy, Office of Industrial Technologies project is developing guided acoustic waves for use on recovery boiler tubing. The feature of this acoustic technique is its cost-effectiveness in inspecting long lengths of tubes from a single inspection point. A piezoelectric or electromagnetic transducer induces guided waves into the tubes. The transducer detects fireside defects from the cold side or fireside of the tube. Cracking and thinning on recovery boiler tubes have been detected with this technique in both laboratory and field applications. This technique appears very promising for recovery boiler tube application, potentially expediting annual inspection of tube integrity.

  1. Electron vortex beams in a magnetic field and spin filter

    E-Print Network [OSTI]

    Debashree Chowdhury; Banasri Basu; Pratul Bandyopadhyay

    2015-02-25T23:59:59.000Z

    We investigate the propagation of electron vortex beams in a magnetic field. It is pointed out that when electron vortex beams carrying orbital angular momentum propagate in a magnetic field, the Berry curvature associated with the scalar electron moving in a cyclic path around the vortex line is modified from that in free space. This alters the spin-orbit interaction, which affects the propagation of nonparaxial beams. The electron vortex beams with tilted vortex lead to spin Hall effect in free space. In presence of a magnetic field in time space we have spin filtering such that either positive or negative spin states emerge in spin Hall currents with clustering of spin $\\frac{1}{2}$ states.

  2. Vortex and Droplet Engineering in Holographic Superconductors

    E-Print Network [OSTI]

    Tameem Albash; Clifford V. Johnson

    2009-08-22T23:59:59.000Z

    We give a detailed account of the construction of non--trivial localized solutions in a 2+1 dimensional model of superconductors using a 3+1 dimensional gravitational dual theory of a black hole coupled to a scalar field. The solutions are found in the presence of a background magnetic field. We use numerical and analytic techniques to solve the full Maxwell--scalar equations of motion in the background geometry, finding condensate droplet solutions, and vortex solutions possessing a conserved winding number. These solutions and their properties, which we uncover, help shed light on key features of the (B,T) phase diagram.

  3. Vortex lattice for a holographic superconductor

    E-Print Network [OSTI]

    Kengo Maeda; Makoto Natsuume; Takashi Okamura

    2009-12-17T23:59:59.000Z

    We investigate the vortex lattice solution in a (2+1)-dimensional holographic model of superconductors constructed from a charged scalar condensate. The solution is obtained perturbatively near the second-order phase transition and is a holographic realization of the Abrikosov lattice. Below a critical value of magnetic field, the solution has a lower free energy than the normal state. Both the free energy density and the superconducting current are expressed by nonlocal functions, but they reduce to the expressions in the Ginzburg-Landau (GL) theory at long wavelength. As a result, a triangular lattice becomes the most favorable solution thermodynamically as in the GL theory of type II superconductors.

  4. Vortex Oscillation Technology Ltd | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTown of Ladoga,planningFlowmeterUtah: Energydba Vision MotorVolusiaVortex

  5. Vortex Hydro Energy LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTri Global EnergyUtility RateVirginia/WindCounty, California |Vortex Hydro

  6. Method of making straight fuel cell tubes

    DOE Patents [OSTI]

    Borglum, Brian P. (Edgewood, PA)

    2001-01-01T23:59:59.000Z

    A method and an apparatus for making straight fuel cell tubes are disclosed. Extruded tubes comprising powders of fuel cell material and a solvent are dried by rotating the extruded tubes. The rotation process provides uniform circumferential drying which results in uniform linear shrinkage of the tubes. The resultant dried tubes are very straight, thereby eliminating subsequent straightening steps required with conventional processes. The method is particularly useful for forming inner air electrode tubes of solid oxide fuel cells.

  7. Improving Vortex Generators to Enhance the Performance of Air-Cooled Condensers in a Geothermal Power Plant

    SciTech Connect (OSTI)

    Manohar S. Sohal

    2005-09-01T23:59:59.000Z

    This report summarizes work at the Idaho National Laboratory to develop strategies to enhance air-side heat transfer in geothermal air-cooled condensers such that it should not significantly increase pressure drop and parasitic fan pumping power. The work was sponsored by the U.S. Department of Energy, NEDO (New Energy and Industrial Technology Development Organization) of Japan, Yokohama National University, and the Indian Institute of Technology, Kanpur, India. A combined experimental and numerical investigation was performed to investigate heat transfer enhancement techniques that may be applicable to largescale air-cooled condensers such as those used in geothermal power applications. A transient heat transfer visualization and measurement technique was employed in order to obtain detailed distributions of local heat transfer coefficients on model fin surfaces. Pressure drop measurements were obtained for a variety of tube and winglet configurations using a single-channel flow apparatus that included four tube rows in a staggered array. Heat transfer and pressure drop measurements were also acquired in a separate multiple-tube row apparatus in the Single Blow Test Facility. In addition, a numerical modeling technique was developed to predict local and average heat transfer for these low-Reynolds number flows, with and without winglets. Representative experimental and numerical results were obtained that reveal quantitative details of local finsurface heat transfer in the vicinity of a circular tube with a single delta winglet pair downstream of the cylinder. Heat transfer and pressure-drop results were obtained for flow Reynolds numbers based on channel height and mean flow velocity ranging from 700 to 6500. The winglets were of triangular (delta) shape with a 1:2 or 1:3 height/length aspect ratio and a height equal to 90% of the channel height. Overall mean fin-surface heat transfer results indicate a significant level of heat transfer enhancement (in terms of Colburn j-factor) associated with deployment of the winglets with circular as well as oval tubes. In general, toe-in (common flow up) type winglets appear to have better performance than the toe-out (common flow down) type winglets. Comparisons of heat transfer and pressure drop results for the elliptical tube versus a circular tube with and without winglets are provided. During the course of their independent research, all of the researchers have established that about 10 to 30% enhancement in Colburn j-factor is expected. However, actual increase in heat transfer rate from a heat exchanger employing finned tubes with winglets may be smaller, perhaps on the order of 2 to 5%. It is also concluded that for any specific application, more full-size experimentation is needed to optimize the winglet design for a specific heat exchanger application. If in place of a circular tube, an oval tube can be economically used in a bundle, it is expected that the pressure drop across the tube bundle with the application of vortex generators (winglets) will be similar to that in a conventional circular tube bundle. It is hoped that the results of this research will demonstrate the benefits of applying vortex generators (winglets) on the fins to improve the heat transfer from the air-side of the tube bundle.

  8. American Institute of Aeronautics and Astronautics Numerical Investigation of the Evolution of Vortex

    E-Print Network [OSTI]

    Rohde, Axel

    and 1000 diameters, alternate vortex shedding begins, and a von Karman vortex street develops in the wake of Vortex Instability in a 2-D Compressible Flow over a Cylinder Axel Rohde Department of Aerospace start and reveals the evolution of vortex instability. After the cylinder has traveled between 100

  9. Non-Riemannian geometry of vortex acoustics

    SciTech Connect (OSTI)

    Garcia de Andrade, L.C. [Departamento de Fisica Teorica, Instituto de Fisica, Universidade Estadual do Rio de Janeiro, Rua Sao Francisco Xavier 524, Maracana, 20550, Rio de Janeiro, RJ (Brazil)

    2004-09-15T23:59:59.000Z

    The concept of acoustic torsion is introduced by making use of the scalar wave equation in Riemann-Cartan spacetime. Acoustic torsion extends the acoustic metric previously given by Unruh (PRL-1981). The wave equation describes irrotational perturbations in rotational nonrelativistic fluids. This physical motivation allows us to show that the acoustic line element can be conformally mapped to the line element of a stationary torsion loop in non-Riemannian gravity. Two examples of such sonic analogues are given. The first is the stationary torsion loop in teleparallel gravity. In the far from the vortex approximation, the Cartan torsion vector is shown to be proportional to the quantum vortex number of the superfluid. The torsion vector is also shown to be proportional to the superfluid vorticity in the presence of vortices. The formation of superfluid vortices is shown not to be favored by torsion loops in Riemann-Cartan spacetime, as long as this model is concerned. It is suggested that the teleparallel model may help to find a model for superfluid neutron stars vortices based on non-Riemannian gravity.

  10. Tube-wave seismic imaging

    DOE Patents [OSTI]

    Korneev, Valeri A. (Lafayette, CA); Bakulin, Andrey (Houston, TX)

    2009-10-13T23:59:59.000Z

    The detailed analysis of cross well seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded approximately 2000 feet above the reservoir. A tube-wave (150) is initiated in a source well (110) by a source (111), travels in the source well (110), is coupled to a geological feature (140), propagates (151) through the geological feature (140), is coupled back to a tube-wave (152) at a receiver well (120), and is and received by receiver(s) (121) in either the same (110) or a different receiving well (120). The tube-wave has been shown to be extremely sensitive to changes in reservoir characteristics. Tube-waves appear to couple most effectively to reservoirs where the well casing is perforated, allowing direct fluid contact from the interior of a well case to the reservoir.

  11. Tube-wave seismic imaging

    DOE Patents [OSTI]

    Korneev, Valeri A [LaFayette, CA

    2009-05-05T23:59:59.000Z

    The detailed analysis of cross well seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded approximately 2000 feet above the reservoir. A tube-wave (150) is initiated in a source well (110) by a source (111), travels in the source well (110), is coupled to a geological feature (140), propagates (151) through the geological feature (140), is coupled back to a tube-wave (152) at a receiver well (120), and is and received by receiver(s) (121) in either the same (110) or a different receiving well (120). The tube-wave has been shown to be extremely sensitive to changes in reservoir characteristics. Tube-waves appear to couple most effectively to reservoirs where the well casing is perforated, allowing direct fluid contact from the interior of a well case to the reservoir.

  12. Steam generator tube rupture study

    E-Print Network [OSTI]

    Free, Scott Thomas

    1986-01-01T23:59:59.000Z

    This report describes our investigation of steam generator behavior during a postulated tube rupture accident. Our study was performed using the steam generator, thermal-hydraulic analysis code THERMIT-UTSG. The purpose ...

  13. Microhole Coiled Tubing Bottom Hole Assemblies

    SciTech Connect (OSTI)

    Don Macune

    2008-06-30T23:59:59.000Z

    The original objective of the project, to deliver an integrated 3 1/8-inch diameter Measurement While Drilling (MWD) and Logging While Drilling (LWD) system for drilling small boreholes using coiled tubing drilling, has been achieved. Two prototype systems have been assembled and tested in the lab. One of the systems has been successfully tested downhole in a conventional rotary drilling environment. Development of the 3 1/8-inch system has also lead to development and commercialization of a slightly larger 3.5-inch diameter system. We are presently filling customer orders for the 3.5-inch system while continuing with commercialization of the 3 1/8-inch system. The equipment developed by this project will be offered for sale to multiple service providers around the world, enabling the more rapid expansion of both coiled tubing drilling and conventional small diameter drilling. The project was based on the reuse of existing technology whenever possible in order to minimize development costs, time, and risks. The project was begun initially by Ultima Labs, at the time a small company ({approx}12 employees) which had successfully developed a number of products for larger oil well service companies. In September, 2006, approximately 20 months after inception of the project, Ultima Labs was acquired by Sondex plc, a worldwide manufacturer of downhole instrumentation for cased hole and drilling applications. The acquisition provided access to proven technology for mud pulse telemetry, downhole directional and natural gamma ray measurements, and surface data acquisition and processing, as well as a global sales and support network. The acquisition accelerated commercialization through existing Sondex customers. Customer demand resulted in changes to the product specification to support hotter (150 C) and deeper drilling (20,000 psi pressure) than originally proposed. The Sondex acquisition resulted in some project delays as the resistivity collar was interfaced to a different MWD system and also as the mechanical design was revised for the new pressure requirements. However, the Sondex acquisition has resulted in a more robust system, secure funding for completion of the project, and more rapid commercialization.

  14. Ferroelectric nanostructure having switchable multi-stable vortex states

    DOE Patents [OSTI]

    Naumov, Ivan I. (Fayetteville, AR); Bellaiche, Laurent M. (Fayetteville, AR); Prosandeev, Sergey A. (Fayetteville, AR); Ponomareva, Inna V. (Fayetteville, AR); Kornev, Igor A. (Fayetteville, AR)

    2009-09-22T23:59:59.000Z

    A ferroelectric nanostructure formed as a low dimensional nano-scale ferroelectric material having at least one vortex ring of polarization generating an ordered toroid moment switchable between multi-stable states. A stress-free ferroelectric nanodot under open-circuit-like electrical boundary conditions maintains such a vortex structure for their local dipoles when subject to a transverse inhomogeneous static electric field controlling the direction of the macroscopic toroidal moment. Stress is also capable of controlling the vortex's chirality, because of the electromechanical coupling that exists in ferroelectric nanodots.

  15. Uranium Neutron Coincidence Collar Model Utilizing Boron-10 Lined Tubes

    SciTech Connect (OSTI)

    Rogers, Jeremy L.; Ely, James H.; Kouzes, Richard T.; Lintereur, Azaree T.; Siciliano, Edward R.

    2012-09-18T23:59:59.000Z

    The Department of Energy Office of Nuclear Safeguards and Security (NA-241) is supporting the project Coincidence Counting With Boron-Based Alternative Neutron Detection Technology at Pacific Northwest National Laboratory (PNNL) for the development of a 3He proportional counter alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a system based upon 10B-lined proportional tubes in a configuration typical for 3He-based coincidence counter applications. This report, providing results for model development of Alternative Boron-Based Uranium Neutron Coincidence Collar (ABUNCL) designs, is a deliverable under Task 2 of the project.

  16. Sound Wave in Vortex with Sink

    E-Print Network [OSTI]

    Soumen Basak

    2003-11-17T23:59:59.000Z

    Using Komar's definition, we give expressions for the mass and angular momentum of a rotating acoustic black hole. We show that the mass and angular momentum so defined, obey the equilibrium version of the first law of Black Hole thermodynamics. We also show that when a phonon passes by a vortex with a sink, its trajectory is bent. The angle of bending of the sound wave to leading order is quadratic in $A/cb$ and $B/cb$, where $b$ is the impact parameter and $A$ and $B$ are the parameters in the velocity of the fluid flow. The time delay in the propagation of sound wave which to first order depends only on $B/c^2$ and is independent of $A$.

  17. Numerical simulation of swirling flow in complex hydroturbine draft tube using unsteady statistical turbulence models

    SciTech Connect (OSTI)

    Paik, Joongcheol [University of Minnesota; Sotiropoulos, Fotis [University of Minnesota; Sale, Michael J [ORNL

    2005-06-01T23:59:59.000Z

    A numerical method is developed for carrying out unsteady Reynolds-averaged Navier-Stokes (URANS) simulations and detached-eddy simulations (DESs) in complex 3D geometries. The method is applied to simulate incompressible swirling flow in a typical hydroturbine draft tube, which consists of a strongly curved 90 degree elbow and two piers. The governing equations are solved with a second-order-accurate, finite-volume, dual-time-stepping artificial compressibility approach for a Reynolds number of 1.1 million on a mesh with 1.8 million nodes. The geometrical complexities of the draft tube are handled using domain decomposition with overset (chimera) grids. Numerical simulations show that unsteady statistical turbulence models can capture very complex 3D flow phenomena dominated by geometry-induced, large-scale instabilities and unsteady coherent structures such as the onset of vortex breakdown and the formation of the unsteady rope vortex downstream of the turbine runner. Both URANS and DES appear to yield the general shape and magnitude of mean velocity profiles in reasonable agreement with measurements. Significant discrepancies among the DES and URANS predictions of the turbulence statistics are also observed in the straight downstream diffuser.

  18. Fuel injection of coal slurry using vortex nozzles and valves

    DOE Patents [OSTI]

    Holmes, Allen B. (Rockville, MD)

    1989-01-01T23:59:59.000Z

    Injection of atomized coal slurry fuel into an engine combustion chamber is achieved at relatively low pressures by means of a vortex swirl nozzle. The outlet opening of the vortex nozzle is considerably larger than conventional nozzle outlets, thereby eliminating major sources of failure due to clogging by contaminants in the fuel. Control fluid, such as air, may be used to impart vorticity to the slurry and/or purge the nozzle of contaminants during the times between measured slurry charges. The measured slurry charges may be produced by a diaphragm pump or by vortex valves controlled by a separate control fluid. Fluidic circuitry, employing vortex valves to alternatively block and pass cool slurry fuel flow, is disclosed.

  19. Zero-Energy Flows and Vortex Patterns in Quantum Mechanics

    E-Print Network [OSTI]

    Tsunehiro Kobayashi

    2003-02-20T23:59:59.000Z

    We show that zero-energy flows appear in many particle systems as same as in single particle cases in 2-dimensions. Vortex patterns constructed from the zero-energy flows can be investigated in terms of the eigenstates in conjugate spaces of Gel'fand triplets. Stable patterns are written by the superposition of zero-energy eigenstates. On the other hand vortex creations and annihilations are described by the insertions of unstable eigenstates with complex-energy eigenvalues into the stable patterns. Some concrete examples are presented in the 2-dimensional parabolic potential barrier case. %, i.e., $-m \\gamma^2 (x^2+y^2)/2$. We point out three interesting properties of the zero-energy flows; (i) the absolute economy as for the energy consumption, (ii) the infinite variety of the vortex patterns, and (iii) the absolute stability of the vortex patterns .

  20. axisymmetric vortex breakdown: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fluid Motion at the 66th Annual Meeting of the APS Division of Fluid Dynamics. Kleckner, Dustin; Irvine, William T M 2013-01-01 325 The Taylor-vortex dynamo Christophe Gissinger...

  1. Desingularization of periodic vortex sheet roll-up

    SciTech Connect (OSTI)

    Krasny, R.

    1986-08-01T23:59:59.000Z

    The equations governing periodic vortex sheet roll-up from analytic initial data are desingularized. Linear stability analysis shows that this diminishes the vortex sheet model's short wavelength instability, yielding a numerically more tractable set of equations. Computational evidence is presented which indicates that this approximation converges, beyond the critical time of singularity formation in the vortex sheet, if the mesh is refined and the smoothing parameter is reduced in the proper order. The results suggest that the vortex sheet rolls up into a double branched spiral past the critical time. It is demonstrated that either higher machine precision or a spectra filter can be used to maintain computational accuracy as the smoothing parameter is decreased. Some conjectures on the model's long time asymptotic state are given.

  2. Vortex-induced vibration of slender structures in unsteady flow

    E-Print Network [OSTI]

    Liao, Jung-Chi, 1971-

    2002-01-01T23:59:59.000Z

    Vortex-induced vibration (VIV) results in fatigue damage of offshore oil exploration and production structures. In recent years, the offshore industry has begun to employ curved slender structures such as steel catenary ...

  3. Drag amplification and fatigue damage in vortex-induced vibrations

    E-Print Network [OSTI]

    Jhingran, Vikas Gopal

    2008-01-01T23:59:59.000Z

    Fatigue damage and drag force amplification due to Vortex-Induced-Vibrations (VIV) continue to cause significant problems in the design of structures which operate in ocean current environments. These problems are magnified ...

  4. Vortex hair on AdS black holes

    E-Print Network [OSTI]

    Gregory, Ruth; Kubiznak, David; Mann, Robert B; Wills, Danielle

    2014-01-01T23:59:59.000Z

    We analyse vortex hair for charged rotating asymptotically AdS black holes in the abelian Higgs model. We give analytical and numerical arguments to show how the vortex interacts with the horizon of the black hole, and how the solution extends to the boundary. The solution is very close to the corresponding asymptotically flat vortex, once one transforms to a frame that is non-rotating at the boundary. We show that there is a Meissner effect for extremal black holes, with the vortex flux being expelled from sufficiently small black holes. The phase transition is shown to be first order in the presence of rotation, but second order without rotation. We comment on applications to holography.

  5. Shallow gas well drilling with coiled tubing in the San Juan Basin

    SciTech Connect (OSTI)

    Moon, R.G.; Ovitz, R.W.; Guild, G.J.; Biggs, M.D.

    1996-12-31T23:59:59.000Z

    Coiled tubing is being utilized to drill new wells, for re-entry drilling to deepen or laterally extend existing wells, and for underbalanced drilling to prevent formation damage. Less than a decade old, coiled tubing drilling technology is still in its inaugral development stage. Initially, utilizing coiled tubing was viewed as a {open_quotes}science project{close_quotes} to determine the validity of performing drilling operations in-lieu of the conventional rotary rig. Like any new technology, the initial attempts were not always successful, but did show promise as an economical alternative if continued efforts were made in the refinement of equipment and operational procedures. A multiwell project has been completed in the San Juan Basin of Northwestern New Mexico which provides documentation indicating that coiled tubing can be an alternative to the conventional rotary rig. A 3-well pilot project, a 6-well project was completed uniquely utilizing the combined resources of a coiled tubing service company, a producing company, and a drilling contractor. This combination of resources aided in the refinement of surface equipment, personnel, mud systems, jointed pipe handling, and mobilization. The results of the project indicate that utilization of coiled tubing for the specific wells drilled was an economical alternative to the conventional rotary rig for drilling shallow gas wells.

  6. Nonclassicality of vortex Airy beams in the Wigner representation

    SciTech Connect (OSTI)

    Chen Ruipin [School of Sciences, Zhejiang A and F University, Lin'an, Zhejiang Province 311300 (China); Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Ooi, C. H. Raymond [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2011-10-15T23:59:59.000Z

    The Wigner distribution function (WDF) of a vortex Airy beam is calculated analytically. The WDF provides intuitive pictures of the intriguing features of vorticity in phase space. The nonclassical property of the vortex Airy beam and the Airy beam is analyzed through the negative parts of the WDF. The study shows that destructive interference of certain classical waves can mimic nonclassical lights such as those due to quantum effects.

  7. Opposed slant tube diabatic sorber

    DOE Patents [OSTI]

    Erickson, Donald C.

    2004-01-20T23:59:59.000Z

    A sorber comprised of at least three concentric coils of tubing contained in a shell with a flow path for liquid sorbent in one direction, a flow path for heat transfer fluid which is in counter-current heat exchange relationship with sorbent flow, a sorbate vapor port in communication with at least one of sorbent inlet or exit ports, wherein each coil is coiled in opposite direction to those coils adjoining it, whereby the opposed slant tube configuration is achieved, with structure for flow modification in the core space inside the innermost coil.

  8. Flash photolysis-shock tube studies

    SciTech Connect (OSTI)

    Michael, J.V. [Argonne National Laboratory, IL (United States)

    1993-12-01T23:59:59.000Z

    Even though this project in the past has concentrated on the measurement of thermal bimolecular reactions of atomic species with stable molecules by the flash or laser photolysis-shock tube (FP- or LP-ST) method using atomic resonance absorption spectrometry (ARAS) as the diagnostic technique, during the past year the authors have concentrated on studies of the thermal decompositions of selected chlorocarbon molecules. These studies are necessary if the degradation of chlorine containing organic molecules by incineration are to be understood at the molecular level. Clearly, destruction of these molecules will not only involve abstraction reactions, when possible, but also thermal decomposition followed by secondary reactions of the initially formed atoms and radicals. Studies on the thermal decomposition of CH{sub 3}Cl are complete, and the curve-of-growth for Cl-atom atomic resonance absorption has been determined. The new thermal decomposition studies are similar to those already reported for CH{sub 3}Cl.

  9. Erosion of heat exchanger tubes in fluidized beds. Annual report, 1990

    SciTech Connect (OSTI)

    Johnson, E.K.; Flemmer, R.L.C.

    1991-01-01T23:59:59.000Z

    This final report describes the activities of the 3-year project entitled ``Erosion of Heat Exchanger Tubes In Fluidized Beds.`` which was completed at the end of 1990. Project accomplishments include the collection of a substantial body of wear data In a 24in. {times} 24in. fluidized bed, comparative wear results In a 6in. {times} 6in. fluidized bed, the development of a dragometer and the collection of a comprehensive set of drag force data in the 24in. {times} 24in. bed, Fast Fourier Transform (FFT) analysis of bubble probe data to establish dominant bubble frequencies in the 24in. {times} 24in. bed, the use of a heat flux gauge for measurement of heat transfer coefficients in the 24in. {times} 24in. bed and the modeling of the tube wear in the 24in. {times} 24in. bed. Analysis of the wear data from the 24in. square bed indicates that tube wear increases with increase in superficial velocity, and with increase in tube height. The latter effect is a result of the tubes higher up in the bed seeing greater movement of dense phase than tubes lower down In the bed. In addition, tube wear was found to decrease with increase in particle size, for constant superficial velocity. Three models of tube wear were formulated and provided acceptable prediction of wear when compared with the experimental data.

  10. Dissipative dynamics of a vortex state in a trapped Bose-condensed gas

    E-Print Network [OSTI]

    P. O. Fedichev; G. V. Shlyapnikov

    1999-06-15T23:59:59.000Z

    We discuss dissipative dynamics of a vortex state in a trapped Bose-condensed gas at finite temperature and draw a scenario of decay of this state in a static trap. The interaction of the vortex with the thermal cloud transfers energy from the vortex to the cloud and induces the motion of the vortex core to the border of the condensate. Once the vortex reaches the border, it immediately decays through the creation of excitations. We calculate the characteristic life-time of a vortex state and address the question of how the dissipative dynamics of vortices can be studied experimentally.

  11. Apparatus for connecting aligned abutted tubes

    DOE Patents [OSTI]

    Williams, R.E.

    1984-11-29T23:59:59.000Z

    An apparatus for connecting abutted tubes and for maintaining their rotary alignment during connection. The apparatus comprises first and second tubes, a rotation prevention element, a collar and a retainer. Each tube has inside and outside walls, and first and second ends, each end having an inside and outside edge. The first tube has portions defining a first plurality of cavities located at the outside edge of its first end. An external threaded portion is on the outside wall of the first tube and next to the first plurality of cavities. The second tube has portions defining a second plurality of cavities located at the outside edge of its first end. The first plurality has a different number than the second plurality. The first ends of the first and second tubes have substantially the same outside diameter and are abutted during connection so that an orifice is formed whenever first and second tube cavities substantially overlap. A rotation prevension element is placed in the orifice to prevent rotation of the first and second tubes. A collar with an internal threaded portion is slidably disposed about the second tube. The internal threaded portion engages the external threaded portion of the first tube to connect the tubes. A lip connected to the collar prevents separation of the collar from the second tube.

  12. Alleviation of fuselage form drag using vortex flows: Final report

    SciTech Connect (OSTI)

    Wortman, A.

    1987-09-15T23:59:59.000Z

    The concept of using vortex generators to reduce the fuselage form drag of transport aircraft combines the outflow from the plane of symmetry which is induced by the rotational component of the vortex flow with the energization of the boundary layer to reduce the momentum thickness and to delay or eliminate flow separation. This idea was first advanced by the author in 1981. Under a DOE grant, the concept was validated in wind tunnel tests of approximately 1:17 scale models of fuselages of Boeing 747 and Lockheed C-5 aircraft. The search for the minimum drag involved three vortex generator configurations with three sizes of each in six locations clustered in the aft regions of the fuselages at the beginning of the tail upsweep. The local Reynolds number, which is referred to the length of boundary layer run from the nose, was approximately 10{sup 7} so that a fully developed turbulent boundary layer was present. Vortex generator planforms ranged from swept tapered, through swept straight, to swept reverse tapered wings whose semi-spans ranged from 50% to 125% of the local boundary layer thickness. Pitch angles of the vortex generators were varied by inboard actuators under the control of an external proportional digital radio controller. It was found that certain combinations of vortex generator parameters increased drag. However, with certain configurations, locations, and pitch angles of vortex generators, the highest drag reductions were 3% for the 747 and about 6% for the C-5, thus confirming the arguments that effectiveness increases with the rate of upsweep of the tail. Greatest gains in performance are therefore expected on aft loading military transports. 10 refs., 11 figs., 1 tab.

  13. Fracture compliance estimation using borehole tube waves

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    We tested two models, one for tube-wave generation and the other for tube-wave attenuation at a fracture intersecting a borehole that can be used to estimate fracture compliance, fracture aperture, and lateral extent. In ...

  14. Two phase flow in capillary tubes

    E-Print Network [OSTI]

    Suo, Mikio

    1963-01-01T23:59:59.000Z

    The flow of two phases, gas and liquid, has been studied in horizontal tubes of capillary diameter. The flow has been primarily studied in the regime where the gas flows as long bubbles separated from the wall of the tube ...

  15. Performance of drift tubes under high radiation

    E-Print Network [OSTI]

    Shi, Yue, S.B. Massachusetts Institute of Technology

    2005-01-01T23:59:59.000Z

    In this thesis, the aging and the rejuvenation of an ATLAS proportional drift tube are described. Firstly, the Diethorn model of gain is tested using pressure and sense-wire voltage measurements. The drift tube was then ...

  16. A PARAMETER STUDY FOR BAROCLINIC VORTEX AMPLIFICATION

    SciTech Connect (OSTI)

    Raettig, Natalie; Klahr, Hubert [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Lyra, Wladimir, E-mail: raettig@mpia.de, E-mail: klahr@mpia.de, E-mail: Wladimir.Lyra@jpl.nasa.gov [Department of Astrophysics, American Museum of Natural History, 79th Street at Central Park West, New York, NY 10024 (United States)

    2013-03-10T23:59:59.000Z

    Recent studies have shown that baroclinic vortex amplification is strongly dependent on certain factors, namely, the global entropy gradient, the efficiency of thermal diffusion and/or relaxation as well as numerical resolution. We conduct a comprehensive study of a broad range and combination of various entropy gradients, thermal diffusion and thermal relaxation timescales via local shearing sheet simulations covering the parameter space relevant for protoplanetary disks. We measure the Reynolds stresses as a function of our control parameters and see that there is angular momentum transport even for entropy gradients as low as {beta} = -dln s/dln r = 1/2. Values we expect in protoplanetary disks are between {beta} = 0.5-2.0 The amplification-rate of the perturbations, {Gamma}, appears to be proportional to {beta}{sup 2} and thus proportional to the square of the Brunt-Vaeisaelae frequency ({Gamma}{proportional_to}{beta}{sup 2}{proportional_to}N {sup 2}). The saturation level of Reynolds stresses, on the other hand, seems to be proportional to {beta}{sup 1/2}. This highlights the importance of baroclinic effects even for the low entropy gradients expected in protoplanetary disks.

  17. Ultra-Low NOx Advanced Vortex Combustor

    SciTech Connect (OSTI)

    Edmonds, R.G. (Ramgen Power Systems, Inc., Bellevue, WA); Steele, R.C. (Ramgen Power Systems, Inc., Bellevue, WA); Williams, J.T. (Ramgen Power Systems, Inc., Bellevue, WA); Straub, D.L.; Casleton, K.H.; Bining, Avtar (California Energy Commission, Sacramento, CA)

    2006-05-01T23:59:59.000Z

    An ultra lean-premixed Advanced Vortex Combustor (AVC) has been developed and tested. The natural gas fueled AVC was tested at the U.S. Department of Energy’s National Energy Technology Laboratory (USDOE NETL) test facility in Morgantown (WV). All testing was performed at elevated pressures and inlet temperatures and at lean fuel-air ratios representative of industrial gas turbines. The improved AVC design exhibited simultaneous NOx/CO/UHC emissions of 4/4/0 ppmv (all emissions are at 15% O2 dry). The design also achieved less than 3 ppmv NOx with combustion efficiencies in excess of 99.5%. The design demonstrated tremendous acoustic dynamic stability over a wide range of operating conditions which potentially makes this approach significantly more attractive than other lean premixed combustion approaches. In addition, a pressure drop of 1.75% was measured which is significantly lower than conventional gas turbine combustors. Potentially, this lower pressure drop characteristic of the AVC concept translates into overall gas turbine cycle efficiency improvements of up to one full percentage point. The relatively high velocities and low pressure drops achievable with this technology make the AVC approach an attractive alternative for syngas fuel applications.

  18. ULTRA-LOW NOX ADVANCED VORTEX COMBUSTOR

    SciTech Connect (OSTI)

    Ryan G. Edmonds; Robert C. Steele; Joseph T. Williams; Douglas L. Straub; Kent H. Casleton; Avtar Bining

    2006-05-01T23:59:59.000Z

    An ultra lean-premixed Advanced Vortex Combustor (AVC) has been developed and tested. The natural gas fueled AVC was tested at the U.S. Department of Energy’s National Energy Technology Laboratory (USDOE NETL) test facility in Morgantown (WV). All testing was performed at elevated pressures and inlet temperatures and at lean fuel-air ratios representative of industrial gas turbines. The improved AVC design exhibited simultaneous NOx/CO/UHC emissions of 4/4/0 ppmv (all emissions are at 15% O2 dry). The design also achieved less than 3 ppmv NOx with combustion efficiencies in excess of 99.5%. The design demonstrated tremendous acoustic dynamic stability over a wide range of operating conditions which potentially makes this approach significantly more attractive than other lean premixed combustion approaches. In addition, a pressure drop of 1.75% was measured which is significantly lower than conventional gas turbine combustors. Potentially, this lower pressure drop characteristic of the AVC concept translates into overall gas turbine cycle efficiency improvements of up to one full percentage point. The relatively high velocities and low pressure drops achievable with this technology make the AVC approach an attractive alternative for syngas fuel applications.

  19. Stability of tube rows in crossflow. [LMFBR

    SciTech Connect (OSTI)

    Chen, S.S.; Jendrzejczyk, J.A.

    1982-10-01T23:59:59.000Z

    A mathematical model for the instability of tube rows subjected to crossflow is examined. The theoretical model, based on the fluid-force data for a pitch-to-diameter ratio of 1.33, provides additional insight into the instability phenomenon. Tests are also conducted for three sets of tube rows. The effects of mass ratio, tube pitch, damping, detuning and finned tubes are investigated. Theoretical results and experimental data are in good agreement.

  20. Visualization of Intricate Flow Structures for Vortex Breakdown Analysis Xavier Tricoche

    E-Print Network [OSTI]

    Utah, University of

    Visualization of Intricate Flow Structures for Vortex Breakdown Analysis Xavier Tricoche University, synthetic depictions that permit new insight into the structural properties of vortex breakdowns. CR And Modeling-- Simulation Output Analysis J.2 [Physical Sciences and Engineer- ing]: Engineering--. Keywords

  1. Experimental Investigations of Vortex Induced Vibration of A Flat Plate in Pitch Oscillation

    E-Print Network [OSTI]

    Yang, Yi

    2012-02-14T23:59:59.000Z

    A bluff structure placed in a flowing fluid, may be subjected to vortex-induced vibrations (VIV). For a flat plate with only rotational degree of freedom, the VIV is rotational oscillation. Based on the experimental investigation, vortex...

  2. X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in...

  3. Vortex in a relativistic perfect isentropic fluid and Nambu Goto dynamics

    E-Print Network [OSTI]

    B. Boisseau

    1999-11-26T23:59:59.000Z

    By a weak deformation of the cylindrical symmetry of the potential vortex in a relativistic perfect isentropic fluid, we study the possible dynamics of the central line of this vortex. In "stiff" material the Nanbu-Goto equations are obtained

  4. Vortex Shedding from Superhydrophobic Cylinders Nangelie Ferrer, Robert Daniello and Jonathan Rothstein

    E-Print Network [OSTI]

    Mountziaris, T. J.

    Vortex Shedding from Superhydrophobic Cylinders Nangelie Ferrer, Robert Daniello and Jonathan Rothstein University of Massachusetts Amherst Abstract Superhydrophobic surfaces are ideal for applications to characterize the vortex shedding phenomenon observed within the wake region of the superhydrophobic cylinder

  5. Spring/dimple instrument tube restraint

    DOE Patents [OSTI]

    DeMario, E.E.; Lawson, C.N.

    1993-11-23T23:59:59.000Z

    A nuclear fuel assembly for a pressurized water nuclear reactor has a spring and dimple structure formed in a non-radioactive insert tube placed in the top of a sensor receiving instrumentation tube thimble disposed in the fuel assembly and attached at a top nozzle, a bottom nozzle, and intermediate grids. The instrumentation tube thimble is open at the top, where the sensor or its connection extends through the cooling water for coupling to a sensor signal processor. The spring and dimple insert tube is mounted within the instrumentation tube thimble and extends downwardly adjacent the top. The springs and dimples restrain the sensor and its connections against lateral displacement causing impact with the instrumentation tube thimble due to the strong axial flow of cooling water. The instrumentation tube has a stainless steel outer sleeve and a zirconium alloy inner sleeve below the insert tube adjacent the top. The insert tube is relatively non-radioactivated inconel alloy. The opposed springs and dimples are formed on diametrically opposite inner walls of the insert tube, the springs being formed as spaced axial cuts in the insert tube, with a web of the insert tube between the cuts bowed radially inwardly for forming the spring, and the dimples being formed as radially inward protrusions opposed to the springs. 7 figures.

  6. Manual tube-to-tubesheet welding torch

    DOE Patents [OSTI]

    Kiefer, Joseph H. (Tampa, FL); Smith, Danny J. (Tampa, FL)

    1982-01-01T23:59:59.000Z

    A welding torch made of a high temperature plastic which fits over a tube intermediate the ends thereof for welding the juncture between the tube and the back side of a tube plate and has a ballooned end in which an electrode, filler wire guide, fiber optic bundle, and blanketing gas duct are disposed.

  7. Studies of Degraded Smelt Spout Opening Tubes

    SciTech Connect (OSTI)

    Keiser, James R [ORNL; Kish, Joseph R. [Paprican; Willoughby, Adam W [ORNL; Longmire, Hu Foster [ORNL; Singbeil, Douglas [Paprican

    2007-01-01T23:59:59.000Z

    Co-extruded type 304L stainless steel/SA210 carbon steel tubes have been used on the floors and lower walls of many black liquor recovery boilers to address the wall thinning problem that had been an issue for boiler owners and operators. Use of these tubes greatly reduced the corrosion issue, but corrosion was still sometimes observed and cracking was discovered in some tubes, particularly those that are bent to form the openings for smelt spouts. Because cracks in the opening tubes were sometimes observed to extend a significant distance into the tube wall and because these cracks were found fairly frequently, tubes made from a number of alternate cladding materials were tried in place of the 304L clad opening tubes. This paper describes the results of examinations of spout opening tubes of the standard 304L/carbon steel and of several of the alternate materials that have been tried. In addition to the corrosion and cracking seen in the spout opening tubes, another issue associated with these tubes has been observed. Preferential corrosion of the cap welds is sometimes seen on butt welds attaching the spout opening tubes made with alternate cladding materials to the standard 304L/carbon steel co-extruded wall tubes. Some information on the observations of this corrosion is also included in this paper.

  8. Tubing carried perforating gun with insulation jacket

    SciTech Connect (OSTI)

    Donovan, J.F.; Yates, D.N.

    1991-05-21T23:59:59.000Z

    This patent describes a method of insulating a tubing carried perforating gun which is run through a subterranean wellbore. It includes making up at the well surface a tubing string for introduction within the well, the tubing string carrying a perforating gun assembly.

  9. Wave–vortex interactions in the nonlinear Schrödinger equation

    SciTech Connect (OSTI)

    Guo, Yuan, E-mail: yuanguo@cims.nyu.edu; Bühler, Oliver [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)] [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)

    2014-02-15T23:59:59.000Z

    This is a theoretical study of wave–vortex interaction effects in the two-dimensional nonlinear Schrödinger equation, which is a useful conceptual model for the limiting dynamics of superfluid quantum condensates at zero temperature. The particular wave–vortex interaction effects are associated with the scattering and refraction of small-scale linear waves by the straining flows induced by quantized point vortices and, crucially, with the concomitant nonlinear back-reaction, the remote recoil, that these scattered waves exert on the vortices. Our detailed model is a narrow, slowly varying wavetrain of small-amplitude waves refracted by one or two vortices. Weak interactions are studied using a suitable perturbation method in which the nonlinear recoil force on the vortex then arises at second order in wave amplitude, and is computed in terms of a Magnus-type force expression for both finite and infinite wavetrains. In the case of an infinite wavetrain, an explicit asymptotic formula for the scattering angle is also derived and cross-checked against numerical ray tracing. Finally, under suitable conditions a wavetrain can be so strongly refracted that it collapses all the way onto a zero-size point vortex. This is a strong wave–vortex interaction by definition. The conditions for such a collapse are derived and the validity of ray tracing theory during the singular collapse is investigated.

  10. Ionization tube simmer current circuit

    DOE Patents [OSTI]

    Steinkraus, Jr., Robert F. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current.

  11. Ionization tube simmer current circuit

    DOE Patents [OSTI]

    Steinkraus, R.F. Jr.

    1994-12-13T23:59:59.000Z

    A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current. 6 figures.

  12. Cold cathode vacuum discharge tube

    DOE Patents [OSTI]

    Boettcher, Gordon E. (Albuquerque, NM)

    1998-01-01T23:59:59.000Z

    A cold cathode vacuum discharge tube, and method for making same, with an interior surface of the trigger probe coated with carbon deposited by carbon vapor deposition (CVD) or diamond-like carbon (DLC) deposition. Preferably a solid graphite insert is employed in the probe-cathode structure in place of an aluminum bushing employed in the prior art. The CVD or DLC probe face is laser scribed to allow resistance trimming to match available trigger voltage signals and to reduce electrical aging.

  13. Vortex and structural dynamics of a flexible cylinder in cross-flow

    SciTech Connect (OSTI)

    Shang, Jessica K., E-mail: jshang@princeton.edu; Stone, Howard A. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Smits, Alexander J. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Monash University, VIC 3800 (Australia)

    2014-05-15T23:59:59.000Z

    A low-density, flexible cantilevered cylinder was permitted to vibrate freely under the influence of vortex shedding in the laminar flow regime. We find that the vortex-induced vibrations (VIV) of a flexible cantilever depart from those of a flexible cylinder that is fixed at both ends. In particular, we find discontinuous regions of VIV behavior – here called states – as a function of the reduced velocity U{sup *}. These states are demarcated by discrete changes in the dominant eigenmodes of the structural response as the cylinder vibrates in progressively higher structural modes with increasing U{sup *}. The contribution of structural modes can be identified readily by a modal projection of the cylinder oscillation onto known cantilever beam modes. Oscillation frequencies do not monotonically increase with U{sup *}. The wake response between different states is also found to have distinct characteristics; of particular note is the occurrence of a P+S wake over one of these regions, which is associated with a high-amplitude vibration of the cylinder that is due to the constructive interference of contributing eigenmodes.

  14. Vortex Interactions and Barotropic Aspects of Concentric Eyewall Formation HUNG-CHI KUO

    E-Print Network [OSTI]

    Schubert, Wayne H.

    of a tropical cyclone core with nearby weaker vorticity of various spatial scales. This paper considers, separation distance, companion vortex size, and core vortex skirt parameter. A vorticity skirt on the core­6 times as strong as the larger companion vortex. An additional requirement is that the separation

  15. Nonexistence of Lyapunov Functions and the Instability of the von Karman Vortex Streets

    E-Print Network [OSTI]

    Lim, Chjan C.

    Nonexistence of Lyapunov Functions and the Instability of the von Karman Vortex Streets Chjan Lim of the von Karman vortex streets and the existence of a global Lyapunov function at the special aspect ratio the equilibrium Karman streets are unlikely theoretical candidates for observed vortex trails. On the other hand

  16. Experimental and Numerical Investigations on the Asymmetric Wake Vortex Structures around an Oscillating Airfoil

    E-Print Network [OSTI]

    Hu, Hui

    of the reverse von Karman vortex street behind the flapping wing. However, it is challenging to fully understandExperimental and Numerical Investigations on the Asymmetric Wake Vortex Structures around of the vortex pair becomes more apparent, which is considered to be a vital element to form the asymmetric wake

  17. The effect of surface tension on the Moore singularity of vortex sheet dynamics

    E-Print Network [OSTI]

    Fontelos, Marco

    The effect of surface tension on the Moore singularity of vortex sheet dynamics F. de la Hoz , M's singularities by surface tension in the evolution of vortex sheets and its dependence on Weber number (which is inversely proportional to surface tension coefficient). The curvature of the vortex sheet, instead

  18. Traveling Waves from the Arclength Parameterization: Vortex Sheets with Surface Tension

    E-Print Network [OSTI]

    Wright, J. Douglas

    Traveling Waves from the Arclength Parameterization: Vortex Sheets with Surface Tension Benjamin for the vortex sheet with surface tension. We use the angle- arclength description of the interface rather than prove that there exist traveling vortex sheets with surface tension bifurcating from equilibrium. We

  19. Turbine nozzle stage having thermocouple guide tube

    DOE Patents [OSTI]

    Schotsch, Margaret Jones (Greer, SC); Kirkpatrick, Francis Lawrence (late of Galway, NY); Lapine, Eric Michael (Northwood, NH)

    2002-01-01T23:59:59.000Z

    A guide tube is fixed adjacent opposite ends in outer and inner covers of a nozzle stage segment. The guide tube is serpentine in shape between the outer and inner covers and extends through a nozzle vane. An insert is disposed in the nozzle vane and has apertures to accommodate serpentine portions of the guide tube. Cooling steam is also supplied through chambers of the insert on opposite sides of a central insert chamber containing the guide tube. The opposite ends of the guide tube are fixed to sleeves, in turn fixed to the outer and inner covers.

  20. Hydrodynamic loads on flexible marine structures due to vortex shedding

    SciTech Connect (OSTI)

    Every, M.J.; King, R.

    1982-12-01T23:59:59.000Z

    This paper makes a comparison of experimental measurements and a recently developed methodology for the prediction of the increase in the steady drag of a cylinder undergoing vortex-induced vibrations. The experimental results were obtained during the development of a means to reduce the flow-induced vibration of a cable-suspended pile of the COGNAC platform installation and agree well with the predictions made in this paper. Next, a brief consideration is made of some of the authors' experience of methods used to reduce vortex-induced vibrations, and hence stress levels. Finally, a reduction method which used an air-blowing manifold is described and results presented.

  1. Aluminum Tape Evaluation for Sealable Aluminum Tubes Containing Mark 22 Fuel Tubes

    SciTech Connect (OSTI)

    RHODES, WILLIAM

    2003-01-01T23:59:59.000Z

    As part of the HEU Blend Down project, aluminum tape is required to seal aluminum tubes that will hold contaminated Mark 22 fuel tubes for dissolution. From a large field of candidate tapes, Avery Dennison's Fasson 0802 tape (synthetic rubber adhesive system) was found to be acceptable for this application. This tape will disentangle in the normal H-Canyon dissolver solution and have no detrimental effect on the H-Canyon process. Upon placement of Fasson 0802 tape into the dissolver solution, nitric acid will attack and disentangle the block copolymer network and destroy the adhesive nature of the material, resulting in insoluble particles that can be removed via centrifuge operations (cake weight increase of no more than 1 percent). The addition of the tape will not generate off-gas products and the resultant solution characteristics (surface tension, viscosity, density, and disengagement time) will be unaffected. Further, the potential effect on the down-stream evaporation system is negligible. Since the tape will not be placed in a high radiation environment, radiation stability is not an issue. Through detailed discussions with Avery Dennison chemists and based on analytical tests, a fairly detailed understanding of the constituents comprising the proprietary adhesive system has been assembled. Most importantly, chlorine was not detected in the aluminum tape (neutron activation analysis detection limit is 16 ppm). Finally, application of this tape will not impact LEU specifications.

  2. Eur. .I. Mech. B/Fluids, 17, no 4, 5499560, 1998 Experimental evidencefor a new type of stretched vortex

    E-Print Network [OSTI]

    Wesfreid, José Eduardo

    , concentrated vorticity can appear as a result of instabilities such as the BCnard-Von Karman vortex street vortex P. PETITJEANS `*, J. H. ROBRES a, J. E. WESFREID a, N. KEVLAHAN b ABSTRACT. - Experimental vortex (which is a non-confined stretched vortex model) are observed and analyzed, 0 Elsevier, Paris 1

  3. Multi-tube arrangement for combustor and method of making the multi-tube arrangement

    DOE Patents [OSTI]

    Ziminsky, Willy Steve (Simpsonville, SC)

    2012-07-31T23:59:59.000Z

    A fuel injector tube includes a one piece, unitary, polygonal tube having an inlet end and an outlet end. The fuel injector tube further includes a fuel passage extending from the inlet end to the outlet end along a longitudinal axis of the polygonal tube, a plurality of air passages extending from the inlet end to the outlet end and surrounding the fuel passage, and a plurality of fuel holes. Each fuel hole connects an air passage with the fuel passage. The inlet end of the polygonal tube is formed into a fuel tube. A fuel injector includes a plurality of fuel injector tubes and a plate. The plurality of fuel tubes are connected to the plate adjacent the inlet ends of the plurality of fuel injector tubes.

  4. Investigation of Vortex Structures in Gas-Discharge Nonneutral Electron Plasma: II. Vortex Formation, Evolution and Dynamics

    E-Print Network [OSTI]

    Kervalishvili, N A

    2015-01-01T23:59:59.000Z

    The results of experimental investigations of inhomogeneities of gas-discharge nonneutral electron plasma obtained by using the nonperturbing experimental methods [N.A. Kervalishvili, arXiv:1502.02516 [physics.plasm-ph] (2015)] have been presented. Inhomogeneities are the dense solitary vortex structures stretched along the magnetic field, the lifetime of which is much greater than the time of electron-neutral collisions. The processes of formation, evolution and dynamics of vortex structures were studied. The periodic sequence of these processes is described for different geometries of discharge device.

  5. Cold cathode vacuum discharge tube

    DOE Patents [OSTI]

    Boettcher, G.E.

    1998-04-14T23:59:59.000Z

    A cold cathode vacuum discharge tube, and method for making same, with an interior surface of the trigger probe coated with carbon deposited by chemical vapor deposition (CVD) or diamond-like carbon (DLC) deposition are disclosed. Preferably a solid graphite insert is employed in the probe-cathode structure in place of an aluminum bushing employed in the prior art. The CVD or DLC probe face is laser scribed to allow resistance trimming to match available trigger voltage signals and to reduce electrical aging. 14 figs.

  6. Cold cathode vacuum discharge tube

    DOE Patents [OSTI]

    Boettcher, G.E.

    1998-03-10T23:59:59.000Z

    A cold cathode vacuum discharge tube, and method for making same, are disclosed with an interior surface of the trigger probe coated with carbon deposited by carbon vapor deposition (CVD) or diamond-like carbon (DLC) deposition. Preferably a solid graphite insert is employed in the probe-cathode structure in place of an aluminum bushing employed in the prior art. The CVD or DLC probe face is laser scribed to allow resistance trimming to match available trigger voltage signals and to reduce electrical aging. 15 figs.

  7. Project Funding Catalog of Services

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreakingMay 2015 < prev next >Presentations Program4DepartmentProjectProject

  8. MANAGING OXIDE SCALE EXFOLIATION IN BOILERS WITH TP347H SUPERHEATER TUBES

    SciTech Connect (OSTI)

    Sabau, Adrian S [ORNL] [ORNL; Wright, Ian G. [WrightHT, Inc.] [WrightHT, Inc.; Shingledecker, John P. [Electric Power Research Institute (EPRI)] [Electric Power Research Institute (EPRI); Tortorelli, Peter F [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    A model based on a concept of fraction of exfoliated area as a function of oxide scale strain energy was developed to predict the extent of exfoliation of steam-side scale from boiler tube superheater loops. As compared with the Armitt diagram, which can be used to predict when scale damage and exfoliation would be likely to occur, a fraction of exfoliated area approach provides an estimation of mass of scale released and the fraction of tube likely to be blocked by the exfoliation. This paper show results for the extent of blockage expected in a single bend of a superheater loop was predicted as a function of operating time, bend geometry, and outlet steam temperature under realistic service conditions that include outages. The deposits of exfoliated scale were assumed to be distributed horizontally the tubes bends. Three types of bends were considered: regular bends, short bends, and hairpin bends. The progressive increase in steam and tube temperatures along a single loop of superheater tubing and the ensuing variation of oxide scale thickness are considered. Numerical simulation results for a superheater loop made of TP347H austenitic steel indicated that tube blockage fractions larger than 50% are likely to occur within the first two years of boiler operation (with regularly scheduled outages) for outlet tube temperatures of 540-570oC, which is consistent with practical experience. Higher blockage fractions were predicted for tubes with short bends and hairpin bends than for tubes with regular bends, of length that are larger than five internal tube diameters. Finally, the blockage model presented can be used with some confidence to devise operating schedules for managing the consequences of oxide scale exfoliation based on projections of time to some critical blockage fraction for specific boiler operating conditions.

  9. Vortex phase-jitter in acoustically excited bluff body flames

    E-Print Network [OSTI]

    Lieuwen, Timothy C.

    Vortex phase-jitter in acoustically excited bluff body flames Santosh J. Shanbhogue, Michael disturbances. Phase locked particle image velocimetry was carried out over a range of conditions", manifested as cycle-to-cycle variation in flame and vorticity field at the same excitation phase. Phase

  10. Onset of superradiant instabilities in the hydrodynamic vortex model

    E-Print Network [OSTI]

    Shahar Hod

    2014-07-30T23:59:59.000Z

    The hydrodynamic vortex, an effective spacetime geometry for propagating sound waves, is studied analytically. In contrast with the familiar Kerr black-hole spacetime, the hydrodynamic vortex model is described by an effective acoustic geometry which has no horizons. However, this acoustic spacetime possesses an ergoregion, a property which it shares with the rotating Kerr spacetime. It has recently been shown numerically that this physical system is linearly unstable due to the superradiant scattering of sound waves in the ergoregion of the effective spacetime. In the present study we use analytical tools in order to explore the onset of these superradiant instabilities which characterize the effective spacetime geometry. In particular, we derive a simple analytical formula which describes the physical properties of the hydrodynamic vortex system in its critical (marginally-stable) state, the state which marks the boundary between stable and unstable fluid configurations. The analytically derived formula is shown to agree with the recently published numerical data for the hydrodynamic vortex system.

  11. AXISYMMETRIC VORTEX BREAKDOWN IN AN ENCLOSED CYLINDER FLOW.

    E-Print Network [OSTI]

    Lopez, John M.

    into the interior flow from the Ekman boundary layer on the rotating endwall is observed, as is the formation,. The boundary conditions are also defined precisely since the flow is confined in a fixed volume. As Re and and the flow remains oscillatory. This oscillatory behavior is mostly confined to the central vortex region. 2

  12. Modified Black Hole with Polar Jet and Vortex

    E-Print Network [OSTI]

    T. Tmmalm

    2001-12-06T23:59:59.000Z

    There are many models relating an accretion disk of Black Hole to jet outflow. The herein heuristic model describes the continuation of an external accretion disk to an internal accretion disk for less than Black Hole horizon, and subsequent polar jet outflow along polar axis out of polar vortex wherein the event horizon is no longer descriptive.

  13. Creation and pinning of vortex-antivortex pairs

    E-Print Network [OSTI]

    Kim, Sangbum; Hu, Chia-Ren; Andrews, Malcolm J.

    2006-01-01T23:59:59.000Z

    Computer modeling is reported about the creation and pinning of a magnetic vortex-antivortex (V-AV) pair in a superconducting thin film, due to the magnetic field of a vertical magnetic dipole above the film, and two antidot pins inside the film...

  14. -STABILITY AND VORTEX MOTION IN TYPE II SUPERCONDUCTORS

    E-Print Network [OSTI]

    Spirn, Daniel

    -STABILITY AND VORTEX MOTION IN TYPE II SUPERCONDUCTORS MATTHIAS KURZKE AND DANIEL SPIRN Abstract. 1. Introduction 1.1. Physical background. The evolution of a superconducting material is usu- ally of the magnetic field and the electric field potential for a superconducting sample R2 . The parameter

  15. LINEAR DISPERSIVE DECAY ESTIMATES FOR VORTEX SHEETS WITH SURFACE TENSION

    E-Print Network [OSTI]

    Spirn, Daniel

    governing irrotational vortex sheets and water waves with surface tension. Using oscillatory integral order, well- posedness theory poses difficulties; however, local-in-time existence for water waves by the kinematic condition in that the interface does not break. This implies the component of the velocity field

  16. Vortex Shedding on Hydrofoils Its dark and lonely down there...

    E-Print Network [OSTI]

    Vortex Shedding on Hydrofoils Its dark and lonely down there... Improving marine vehicle an underwater vehicle moves, it displaces water, genera6ng a unique velocity that it can u6lize rather than fight those flows, saving energy and improving

  17. Vortex stabilized electron beam compressed fusion grade plasma

    SciTech Connect (OSTI)

    Hershcovitch, Ady [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-03-19T23:59:59.000Z

    Most inertial confinement fusion schemes are comprised of highly compressed dense plasmas. Those schemes involve short, extremely high power, short pulses of beams (lasers, particles) applied to lower density plasmas or solid pellets. An alternative approach could be to shoot an intense electron beam through very dense, atmospheric pressure, vortex stabilized plasma.

  18. Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates

    E-Print Network [OSTI]

    Correggi, Michele

    2012-01-01T23:59:59.000Z

    We consider a 2D rotating Bose gas described by the Gross-Pitaevskii (GP) theory and investigate the properties of the ground state of the theory for rotational speeds close to the critical speed for vortex nucleation. While one could expect that the vortex distribution should be homogeneous within the condensate we prove by means of an asymptotic analysis in the strongly interacting (Thomas-Fermi) regime that it is not. More precisely we rigorously derive a formula due to Sheehy and Radzihovsky [Phys. Rev. A 70, 063620(R) (2004)] for the vortex distribution, a consequence of which is that the vortex distribution is strongly inhomogeneous close to the critical speed and gradually homogeneizes when the rotation speed is increased. From the mathematical point of view, a novelty of our approach is that we do not use any compactness argument in the proof, but instead provide explicit estimates on the difference between the vorticity measure of the GP ground state and the minimizer of a certain renormalized energy...

  19. Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    be homogeneous within the condensate we prove by means of an asymptotic analysis in the strongly interactingInhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates M. Correggia , N. Rougerieb, France. May 10, 2012 Abstract We consider a 2D rotating Bose gas described by the Gross-Pitaevskii (GP

  20. Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    should be homogeneous within the condensate we prove by means of an asymptotic analysis in the stronglyInhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates M. Correggia , N. Rougerieb, France. September 19, 2012 Abstract We consider a 2D rotating Bose gas described by the Gross

  1. Spacetime Defects: von Kármán vortex street like configurations

    E-Print Network [OSTI]

    Patricio S. Letelier

    2001-07-05T23:59:59.000Z

    A special arrangement of spinning strings with dislocations similar to a von K\\'arm\\'an vortex street is studied. We numerically solve the geodesic equations for the special case of a test particle moving along twoinfinite rows of pure dislocations and also discuss the case of pure spinning defects.

  2. Ultrasonic Concentration in a Line-Driven Cylindrical Tube

    SciTech Connect (OSTI)

    G.R. Goddard

    2004-12-15T23:59:59.000Z

    The fractionation of particles from their suspending fluid or noninvasive micromanipulation of particles in suspension has many applications ranging from the recovery of valuable reagents from process flows to the fabrication of microelectromechanical devices. Techniques based on size, density, solubility, or electromagnetic properties exist for fulfilling these needs, but many particles have traits that preclude their use such as small size, neutral buoyancy, or uniform electromagnetic characteristics. While separation by those techniques may not be possible, often compressibility differences exist between the particle and fluid that would allow fractionation by acoustic forces. The potential of acoustic separation is known, but due to inherent difficulties in achieving and maintaining accurate alignment of the transduction system, it is rarely utilized. The objective of this project is to investigate the use of structural excitation as a potentially efficient concentration/fractionation method for particles in suspension. It is demonstrated that structural excitation of a cylindrically symmetric cavity, such as a tube, allows non-invasive, fast, and low power concentration of particles suspended in a fluid. The inherent symmetry of the system eliminates the need for careful alignment inherent in current acoustic concentration devices. Structural excitation distributes the acoustic field throughout the volume of the cavity, which also significantly reduces temperature gradients and acoustic streaming in the fluid; cavitation is no longer an issue. The lowest-order coupled modes of a long cylindrical glass tube and fluid-filled cavity, driven by a line contact, are tuned, via material properties and aspect ratio, to achieve a coupled dipolar vibration of the system, shown to generate efficient concentration of particles to the central axis of the tube. A two dimensional elastodynamic model of the system was developed and subsequently utilized to optimize particle concentration within the system. The effects of tubing, fluid, and particle material properties, tube geometry, fluid flow, and tube length on the structural excitation and consequently power requirements and concentration quality within the tube were investigated theoretically and experimentally. Limitations of the method are discussed, as well as ways to minimize or compensate for deleterious effects. Finally a preliminary demonstration of the efficacy of acoustic concentration is presented.

  3. Large Diameter Lasing Tube Cooling Arrangement

    DOE Patents [OSTI]

    Hall, Jerome P.; Alger, Terry W.; Anderson, Andrew T.; Arnold, Philip A.

    2004-05-18T23:59:59.000Z

    A cooling structure (16) for use inside a ceramic cylindrical tube (11) of a metal vapor laser (10) to cool the plasma in the tube (11), the cooling structure (16) comprising a plurality of circular metal members (17,31) and mounting members (18, 34) that position the metal members (17,31) coaxially in the tube (11) to form an annular lasing volume, with the metal members (17, 31) being axially spaced from each other along the length of the tube (11) to prevent the metal members from shorting out the current flow through the plasma in the tube (11) and to provide spaces through which the heat from localized hot spots in the plasma may radiate to the other side of the tube (11).

  4. Large diameter lasing tube cooling arrangement

    DOE Patents [OSTI]

    Hall, Jerome P. (Livermore, CA); Alger, Terry W. (Tracy, CA); Anderson, Andrew T. (Livermore, CA); Arnold, Phillip A. (Livermore, CA)

    2004-05-18T23:59:59.000Z

    A cooling structure (16) for use inside a ceramic cylindrical tube (11) of a metal vapor laser (10) to cool the plasma in the tube (11), the cooling structure (16) comprising a plurality of circular metal members (17, 31) and mounting members (18, 34) that position the metal members (17, 31) coaxially in the tube (11) to form an annular lasing volume, with the metal members (17, 31) being axially spaced from each other along the length of the tube (11) to prevent the metal members from shorting out the current flow through the plasma in the tube (11) and to provide spaces through which the heat from localized hot spots in the plasma may radiate to the other side of the tube (11).

  5. Tube support grid and spacer therefor

    DOE Patents [OSTI]

    Ringsmuth, Richard J. (Solano Beach, CA); Kaufman, Jay S. (Del Mar, CA)

    1986-01-01T23:59:59.000Z

    A tube support grid and spacers therefor provide radially inward preloading of heat exchange tubes to minimize stress upon base welds due to differential thermal expansion. The grid comprises a concentric series of rings and spacers with opposing concave sides for conforming to the tubes and V-shaped ends to provide resilient flexibility. The flexibility aids in assembly and in transmitting seismic vibrations from the tubes to a shroud. The tube support grid may be assembled in place to achieve the desired inwardly radial preloading of the heat exchange tubes. Tab and slot assembly further minimizes stresses in the system. The radii of the grid rings may be preselected to effect the desired radially inward preloading.

  6. Noncommutative vortices and flux tubes from Yang-Mills theories with spontaneously generated fuzzy extra dimensions

    SciTech Connect (OSTI)

    Kuerkcueoglu, Seckin [Middle East Technical University, Department of Physics, Inoenue Boulevard, 06531, Ankara (Turkey)

    2010-11-15T23:59:59.000Z

    We consider a U(2) Yang-Mills theory on MxS{sub F}{sup 2}, where M is an arbitrary noncommutative manifold, and S{sub F}{sup 2} is a fuzzy sphere spontaneously generated from a noncommutative U(N) Yang-Mills theory on M, coupled to a triplet of scalars in the adjoint of U(N). Employing the SU(2)-equivariant gauge field constructed in [D. Harland and S. Kurkcuoglu, Nucl. Phys. B 821, 380 (2009).], we perform the dimensional reduction of the theory over the fuzzy sphere. The emergent model is a noncommutative U(1) gauge theory coupled adjointly to a set of scalar fields. We study this model on the Groenewald-Moyal plane M=R{sub {theta}}{sup 2} and find that, in certain limits, it admits noncommutative, non-Bogomol'nyi-Prasad-Somerfield vortex as well as flux-tube (fluxon) solutions and discuss some of their properties.

  7. Eddy current measurement of tube element spacing

    DOE Patents [OSTI]

    Latham, Wayne Meredith (Forest, VA); Hancock, Jimmy Wade (Lynchburg, VA); Grut, Jayne Marie (Madison Heights, VA)

    1998-01-01T23:59:59.000Z

    A method of electromagnetically measuring the distance between adjacent tube elements in a heat exchanger. A cylindrical, high magnetic permeability ferrite slug is placed in the tube adjacent the spacing to be measured. A bobbin or annular coil type probe operated in the absolute mode is inserted into a second tube adjacent the spacing to be measured. From prior calibrations on the response of the eddy current coil, the signals from the coil, when sensing the presence of the ferrite slug, are used to determine the spacing between the tubes.

  8. A Built for Purpose Micro-Hole Coiled Tubing Rig (MCTR)

    SciTech Connect (OSTI)

    Bart Patton

    2007-09-30T23:59:59.000Z

    This report will serve as the final report on the work performed from the contract period October 2005 thru April 2007. The project 'A Built for Purpose Microhole Coiled Tubing Rig (MCTR)' purpose was to upgrade an existing state-of-the-art Coiled Tubing Drilling Rig to a Microhole Coiled Tubing Rig (MCTR) capable of meeting the specifications and tasks of the Department of Energy. The individual tasks outlined to meet the Department of Energy's specifications are: (1) Concept and development of lubricator and tool deployment system; (2) Concept and development of process control and data acquisition; (3) Concept and development of safety and efficiency improvements; and (4) Final unit integration and testing. The end result of the MCTR upgrade has produced a unit capable of meeting the following requirements: (1) Capable of handling 1-inch through 2-3/8-inch coiled tubing (Currently dressed for 2-3/8-inch coiled tubing and capable of running up to 3-1/2-inch coiled tubing); (2) Capable of drilling and casing surface, intermediate, production and liner hole intervals; (3) Capable of drilling with coiled tubing and has all controls and installation piping for a top drive; (4) Rig is capable of running 7-5/8-inch range 2 casing; and (5) Capable of drilling 5,000 ft true vertical depth (TVD) and 6,000 ft true measured depth (TMD).

  9. Continuous-wave radar to detect defects within heat exchangers and steam generator tubes.

    SciTech Connect (OSTI)

    Nassersharif, Bahram (New Mexico State University, Las Cruces, NM); Caffey, Thurlow Washburn Howell; Jedlicka, Russell P. (New Mexico State University, Las Cruces, NM); Garcia, Gabe V. (New Mexico State University, Las Cruces, NM); Rochau, Gary Eugene

    2003-01-01T23:59:59.000Z

    A major cause of failures in heat exchangers and steam generators in nuclear power plants is degradation of the tubes within them. The tube failure is often caused by the development of cracks that begin on the outer surface of the tube and propagate both inwards and laterally. A new technique was researched for detection of defects using a continuous-wave radar method within metal tubing. The experimental program resulted in a completed product development schedule and the design of an experimental apparatus for studying handling of the probe and data acquisition. These tests were completed as far as the prototypical probe performance allowed. The prototype probe design did not have sufficient sensitivity to detect a defect signal using the defined radar technique and did not allow successful completion of all of the project milestones. The best results from the prototype probe could not detect a tube defect using the radar principle. Though a more precision probe may be possible, the cost of design and construction was beyond the scope of the project. This report describes the probe development and the status of the design at the termination of the project.

  10. Continuous-Wave Radar to Detect Defects Within Heat Exchangers and Steam Generator Tubes ; Revised September 3, 2003

    SciTech Connect (OSTI)

    Gary E. Rochau and Thurlow W.H. Caffey, Sandia National Laboratories, Albuquerque, NM 87185-0740; Bahram Nassersharif and Gabe V. Garcia, Department of Mechanical Engineering, New Mexico State University, Las Cruces, NM 88003-8001; Russell P. Jedlicka, Klipsch School of Electrical and Computer Engineering, New Mexico State University, Las Cruces, NM 88003-8001

    2003-05-01T23:59:59.000Z

    OAK B204 Continuous-Wave Radar to Detect Defects Within Heat Exchangers and Steam Generator Tubes ; Revised September 3, 2003. A major cause of failures in heat exchangers and steam generators in nuclear power plants is degradation of the tubes within them. The tube failure is often caused by the development of cracks that begin on the outer surface of the tube and propagate both inwards and laterally. A new technique was researched for detection of defects using a continuous-wave radar method within metal tubing. The technique is 100% volumetric, and may find smaller defects, more rapidly, and less expensively than present methods. The project described in this report was a joint development effort between Sandia National Laboratories (SNL) and New Mexico State University (NMSU) funded by the US Department of Energy. The goal of the project was to research, design, and develop a new concept utilizing a continuous wave radar to detect defects inside metallic tubes and in particular nuclear plant steam generator tubing. The project was divided into four parallel tracks: computational modeling, experimental prototyping, thermo-mechanical design, and signal detection and analysis.

  11. Pool boiling of R-114/oil mixtures from single tubes and tube bundles. Master's thesis

    SciTech Connect (OSTI)

    Murphy, T.J.

    1987-09-01T23:59:59.000Z

    An apparatus was designed, fabricated, and operated for the testing of horizontal tube bundles for boiling of R-114 with various concentrations of oil. Preliminary data were taken on the top tube in the bundle, with and without the other tubes in operation. Results showed up to a 37% increase in the boiling heat-transfer coefficient as a result of the favorable bundle effect. In a separate single-tube apparatus, three enhanced tubes were tested at a saturation temperature of 2.2 C with oil mass concentrations of 0, 1, 2, 3, 6 and 10%. The tubes were: 1) a finned tube with 1024 fins per meter, 2) a finned tube with 1575 fins per meter and 3) a Turbo-B tube. These tubes resulted in enhancement ratios in pure refrigerant of 2.8, 3.8 and 5.2, respectively, at a practical heat flux of 30 kW/sq. meter. With 3% oil, these ratios were decreased to 2.6, 3.5 and 5, while with 10% oil, these ratios were further reduced to 2.6, 3.2 and 4.7, respectively. Based on these results, the use of Turbo-B tubes is expected to result in significant savings in weight and size of evaporators over the finned tubes presently in use on board some naval vessels.

  12. Sampling Artifacts from Conductive Silicone Tubing

    SciTech Connect (OSTI)

    Timko, Michael T.; Yu, Zhenhong; Kroll, Jesse; Jayne, John T.; Worsnop, Douglas R.; Miake-Lye, Richard C.; Onasch, Timothy B.; Liscinsky, David; Kirchstetter, Thomas W.; Destaillats, Hugo; Holder, Amara L.; Smith, Jared D.; Wilson, Kevin R.

    2009-05-15T23:59:59.000Z

    We report evidence that carbon impregnated conductive silicone tubing used in aerosol sampling systems can introduce two types of experimental artifacts: 1) silicon tubing dynamically absorbs carbon dioxide gas, requiring greater than 5 minutes to reach equilibrium and 2) silicone tubing emits organic contaminants containing siloxane that adsorb onto particles traveling through it and onto downstream quartz fiber filters. The consequence can be substantial for engine exhaust measurements as both artifacts directly impact calculations of particulate mass-based emission indices. The emission of contaminants from the silicone tubing can result in overestimation of organic particle mass concentrations based on real-time aerosol mass spectrometry and the off-line thermal analysis of quartz filters. The adsorption of siloxane contaminants can affect the surface properties of aerosol particles; we observed a marked reduction in the water-affinity of soot particles passed through conductive silicone tubing. These combined observations suggest that the silicone tubing artifacts may have wide consequence for the aerosol community and should, therefore, be used with caution. Gentle heating, physical and chemical properties of the particle carriers, exposure to solvents, and tubing age may influence siloxane uptake. The amount of contamination is expected to increase as the tubing surface area increases and as the particle surface area increases. The effect is observed at ambient temperature and enhanced by mild heating (<100 oC). Further evaluation is warranted.

  13. Composite tube cracking in kraft recovery boilers: A state-of-the-art review

    SciTech Connect (OSTI)

    Singbeil, D.L.; Prescott, R. [Pulp and Paper Research Inst. of Canada, Vancouver, British Columbia (Canada); Keiser, J.R.; Swindeman, R.W. [Oak Ridge National Lab., TN (United States)

    1997-07-01T23:59:59.000Z

    Beginning in the mid-1960s, increasing energy costs in Finland and Sweden made energy recovery more critical to the cost-effective operation of a kraft pulp mill. Boiler designers responded to this need by raising the steam operating pressure, but almost immediately the wall tubes in these new boilers began to corrode rapidly. Test panels installed in the walls of the most severely corroding boiler identified austenitic stainless steel as sufficiently resistant to the new corrosive conditions, and discussions with Sandvik AB, a Swedish tube manufacturer, led to the suggestion that coextruded tubes be used for water wall service in kraft recovery boilers. Replacement of carbon steel by coextruded tubes has solved most of the corrosion problems experienced by carbon steel wall tubes, however, these tubes have not been problem-free. Beginning in early 1995, a multidisciplinary research program funded by the US Department of Energy was established to investigate the cause of cracking in coextruded tubes and to develop improved materials for use in water walls and floors of kraft recovery boilers. One portion of that program, a state-of-the-art review of public- and private-domain documents related to coextruded tube cracking in kraft recovery boilers is reported here. Sources of information that were consulted for this review include the following: tube manufacturers, boiler manufacturers, public-domain literature, companies operating kraft recovery boilers, consultants and failure analysis laboratories, and failure analyses conducted specifically for this project. Much of the information contained in this report involves cracking problems experienced in recovery boiler floors and those aspects of spout and air-port-opening cracking not readily attributable to thermal fatigue. 61 refs.

  14. Pressurized water nuclear reactor system with hot leg vortex mitigator

    DOE Patents [OSTI]

    Lau, Louis K. S. (Monroeville, PA)

    1990-01-01T23:59:59.000Z

    A pressurized water nuclear reactor system includes a vortex mitigator in the form of a cylindrical conduit between the hot leg conduit and a first section of residual heat removal conduit, which conduit leads to a pump and a second section of residual heat removal conduit leading back to the reactor pressure vessel. The cylindrical conduit is of such a size that where the hot leg has an inner diameter D.sub.1, the first section has an inner diameter D.sub.2, and the cylindrical conduit or step nozzle has a length L and an inner diameter of D.sub.3 ; D.sub.3 /D.sub.1 is at least 0.55, D.sub.2 is at least 1.9, and L/D.sub.3 is at least 1.44, whereby cavitation of the pump by a vortex formed in the hot leg is prevented.

  15. Vortex energy and 360 Neel walls in thinfilm

    E-Print Network [OSTI]

    .Ignat@math.u-psud.fr) Courant Institute, New York University, New York, NY 10012, USA (e-mail: knuepfer@cims.nyu.edu) 1 #12Vortex energy and 360 ­N´eel walls in thin­film micromagnetics Radu Ignat , Hans Kn¨upfer October-section. The model is based on the following energy functional: E2d (m) = Z B2 |m|2 dx + | ln | 2 Z R2 ||-1

  16. Vortex topology and the continuum limit of lattice gauge theories

    E-Print Network [OSTI]

    G. Burgio

    2007-10-02T23:59:59.000Z

    We study the stability of Z_2 topological vortex excitations in d+1 dimensional SU(2) Yang-Mills theory on the lattice at T=0. This is found to depend on d and on the coupling considered. We discuss the connection with lattice artifacts causing bulk transitions in the beta_A-beta_F plane and draw some conclusions regarding the continuum limit of the theory.

  17. Reduction of the planar 4-vortex system at zero momentum

    E-Print Network [OSTI]

    Patrick, George

    in the plane the nth vortex has location zn = xn + iyn Ppl (C2 )N . The Hamiltonian and symplectic form- nally on each factor C of Ppl by (ei , a) · z ei z + a. A momentum mapping is Jpl - N n=1 n 1 2 |zn|2]. To calculate the quotient µe : (Jpl )-1 (µe) (Ppl )µe (Jpl )-1 (µe)/SE(2), one may first translate

  18. Vortex energy and 360 Neel wall in thinfilm

    E-Print Network [OSTI]

    Ignat, Radu

    .Ignat@math.u-psud.fr) Courant Institute, New York University, New York, NY 10012, USA (e-mail: knuepfer@cims.nyu.edu) 1 #12Vortex energy and 360 ­N´eel wall in thin­film micromagnetics Radu Ignat , Hans Kn¨upfer October-section. The model is based on the following energy functional: E2d (m) = Z B2 |m|2 dx + | ln | 2 Z R2 ||-1

  19. High-precision calculations of vortex sheet motion

    SciTech Connect (OSTI)

    Ely, J.S. (Lewis and Clark College, Portland, OR (United States)); Baker, G.R. (Ohio State Univ., Columbus, OH (United States))

    1994-04-01T23:59:59.000Z

    The motion of a vortex sheet undergoing Kelvin-Helmholtz instability is known to be ill-posed, causing deterioration in numerical calculations from the rapid growth of round-off errors. In particular, it is the smallest scales (introduced by round-off) that grow the fastest. Krasny introduced a spectral filter to suppress the growth of round-off errors of the smallest scales. He was then able to detect evidence supporting asymptotic studies that indicate the formation of a curvature singularity in finite time. We use high precision interval arithmetic, coded in C + +, to re-examine the evolution of a vortex sheet from initial conditions used previously by several researchers. Most importantly, our results are free from the influence of round-off errors. We show excellent agreement between results obtained through high precision interval arithmetic and through the use of Krasny's spectral filter. In particular, our results support the formation of a curvature singularity in finite time. After the time of singularity formation, the markers move in peculiar patterns. We rule out any possibility of this motion resulting from round-off errors, but it does depend on the level of resolution. We find no consistent behavior in the motion of the markers as we improve the resolution of the vortex sheet. Also, we find some disagreement between the results obtained through high precision interval arithmetic and through the use of the spectral filter. 29 refs., 5 figs.

  20. Horizontal Beam Tubes - HFIR Technical Parameters | ORNL Neutron...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beam Tubes The reactor has four horizontal beam tubes that supply the neutrons to the neutron scattering instruments. Details for each beam tube and instrument can be found on...

  1. Photomultiplier Tubes: Calibration and Neutrino Physics

    SciTech Connect (OSTI)

    Damon, Edward; Maricic, Jelena [Drexel University, Philadelphia, PA 19104 (United States)

    2010-03-30T23:59:59.000Z

    Photomultiplier Tubes are devices designed to amplify very small light signals, on the order of single photons, to levels that are detectable by conventional electronics. Such a high level of amplification, however, comes with a quite a few potential problems, as the relationship between a light signal in and the current out- the response of the system- can be difficult to determine, meaning that photomultiplier tubes' use in scientific research requires a great deal of sensitive calibration. Once calibrated, the photomultiplier tube is a tool that can be used on a number of interesting problems, including the field of neutrino physics. This work deals with the use of photomultiplier tubes' use in the upcoming Double Chooz experiment to determine the mixing angle theta{sub 13}, between different neutrino mass eigenstates. Calibration of the tubes requires measurement of the charge characteristics, most notably, the gain, pedestal, and the dark rate of a tube. Moreover, for all modern tubes, there is an additional feature which can be used to calibrate the system, the single photo electron peak, which describes the response of the tube to a single photon. Some theories predict higher order effects, in addition to the single photoelectron peak, including things like incomplete multiplication of a single photon electron, features which are theoretically able to be determined by a detailed examination of the single photoelectron peak. This paper goes through the methods of calibrating a phototubes both with and without a single photoelectron peak, and is unable to determine conclusively whether or not partial multiplication is able to explain certain features of photomultiplier tubes with a single photoelectron peak.

  2. Multi-tube fuel nozzle with mixing features

    DOE Patents [OSTI]

    Hughes, Michael John

    2014-04-22T23:59:59.000Z

    A system includes a multi-tube fuel nozzle having an inlet plate and a plurality of tubes adjacent the inlet plate. The inlet plate includes a plurality of apertures, and each aperture includes an inlet feature. Each tube of the plurality of tubes is coupled to an aperture of the plurality of apertures. The multi-tube fuel nozzle includes a differential configuration of inlet features among the plurality of tubes.

  3. Scintillation probe with photomultiplier tube saturation indicator

    DOE Patents [OSTI]

    Ruch, Jeffrey F. (Bethel Park, PA); Urban, David J. (Glassport, PA)

    1996-01-01T23:59:59.000Z

    A photomultiplier tube saturation indicator is formed by supplying a supplemental light source, typically an light emitting diode (LED), adjacent to the photomultiplier tube. A switch allows the light source to be activated. The light is forwarded to the photomultiplier tube by an optical fiber. If the probe is properly light tight, then a meter attached to the indicator will register the light from the LED. If the probe is no longer light tight, and the saturation indicator is saturated, no signal will be registered when the LED is activated.

  4. Resonant absorption in dissipative flux tubes

    E-Print Network [OSTI]

    Safari, H; Karami, K; Sobouti, Y

    2005-01-01T23:59:59.000Z

    Oscillations of coronal loops are believed to be the primary cause of the solar corona heating. We study the resonant absorbtion of MHD waves in magnetized flux tubes with graded densities across the cross section of the tube. Within the approximation that resistive and viscous processes are operative in thin layers surrounding the singularities of the MHD equations, we give the full spectrum of the eigenfrequencies, damping rates, as well as, the eigenfields of the normal MHD modes of the tube. Both surface and body modes are analyzed and the contribution of each class to heating of the corona is commented on.

  5. Hydrogen Tube Trailers | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking of Blythe SolarContaminationCurrent Technology »Clean CoalTube Trailers

  6. Alternative Electrostatic Green's Function for a Long Tube. ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Alternative Electrostatic Green's Function for a Long Tube. Alternative Electrostatic Green's Function for a Long Tube. Abstract: This note describes an expression for the...

  7. Electric and Gas Fired Radiant Tubes 'ERT'

    E-Print Network [OSTI]

    Nilsen, E. K.

    1981-01-01T23:59:59.000Z

    The paper covers a unique development by the Surface Division of Midland Ross of a radiant tube heating element which will heat an industrial furnace with either gas or electric without any down time or physical conversion required...

  8. Electric and Gas Fired Radiant Tubes 'ERT' 

    E-Print Network [OSTI]

    Nilsen, E. K.

    1981-01-01T23:59:59.000Z

    The paper covers a unique development by the Surface Division of Midland Ross of a radiant tube heating element which will heat an industrial furnace with either gas or electric without any down time or physical conversion required...

  9. Staged multi-tube premixing injector

    DOE Patents [OSTI]

    Zuo, Baifang; Khan, Abdul Rafey; York, William David; Ziminsky, Willy Steve

    2012-10-02T23:59:59.000Z

    A fuel injection nozzle includes a body member having an upstream wall opposing a downstream wall, and an internal wall disposed between the upstream wall and the downstream wall, a first chamber partially defined by the an inner surface of the upstream wall and a surface of the internal wall, a second chamber partially defined by an inner surface of the downstream wall and a surface of the internal wall a first gas inlet communicative with the first chamber operative to emit a first gas into the first chamber, a second gas inlet communicative with the second chamber operative to emit a second gas into the second chamber, and a plurality of mixing tubes, each of the mixing tubes having a tube inner surface, a tube outer surface, a first inlet communicative with an aperture in the upstream wall operative to receive a third gas.

  10. Forced-convection condensation inside tubes

    E-Print Network [OSTI]

    Traviss, Donald P.

    1971-01-01T23:59:59.000Z

    High vapor velocity condensation inside a tube was studied analytically. The von Karman universal velocity distribution was applied to the condensate flow, pressure drops were calculated using the Lockhart- Martinelli ...

  11. Integrated Projects | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking of BlytheDepartmentEnergy Integrated Energy AnalysisIntegrated Projects

  12. SERC Projects | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreakingMay 2015 <Department of iiBiodiesel | Department ofSERC Projects SERC

  13. Vortex-induced vibration of a circular cylinder with combined in-line and cross-flow motion

    E-Print Network [OSTI]

    Dahl, Jason (Jason Michael)

    2008-01-01T23:59:59.000Z

    Deep water, string-like, marine risers subject to strong ocean currents, suffer from vortex-induced vibrations (VIV), where vortex shedding interacts with the structural properties of the riser, resulting in large amplitude ...

  14. Vortex Hydro Energy Develops Transformational Technology to Harness Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: SinceDevelopment | Department ofPartnerships Toolkit Voluntary Initiative:Departmentfrom Water

  15. Fluidized bed combustor and tube construction therefor

    DOE Patents [OSTI]

    De Feo, Angelo (Passaic, NJ); Hosek, William (Morris, NJ)

    1981-01-01T23:59:59.000Z

    A fluidized bed combustor comprises a reactor or a housing which has a windbox distributor plate adjacent the lower end thereof which contains a multiplicity of hole and air discharge nozzles for discharging air and coal into a fluidized bed which is maintained above the distributor plate and below a take-off connection or flue to a cyclone separator in which some of the products of combustion are treated to remove the dust which is returned into the fluidized bed. A windbox is spaced below the fluidized bed and it has a plurality of tubes passing therethrough with the passage of combustion air and fluidizing air which passes through an air space so that fluidizing air is discharged into the reaction chamber fluidized bed at the bottom thereof to maintain the bed in a fluidized condition. A fluid, such as air, is passed through the tubes which extend through the windbox and provide a preheating of the combustion air and into an annular space between telescoped inner and outer tubes which comprise heat exchanger tubes or cooling tubes which extend upwardly through the distributor plate into the fluidized bed. The heat exchanger tubes are advantageously arranged so that they may be exposed in groups within the reactor in a cluster which is arranged within holding rings.

  16. Tube construction for fluidized bed combustor

    DOE Patents [OSTI]

    De Feo, Angelo (Totowa, NJ); Hosek, William (Mt. Tabor, NJ)

    1984-01-01T23:59:59.000Z

    A fluidized bed combustor comprises a reactor or a housing which has a windbox distributor plate adjacent the lower end thereof which contains a multiplicity of hole and air discharge nozzles for discharging air and coal into a fluidized bed which is maintained above the distributor plate and below a take-off connection or flue to a cyclone separator in which some of the products of combustion are treated to remove the dust which is returned into the fluidized bed. A windbox is spaced below the fluidized bed and it has a plurality of tubes passing therethrough with the passage of combustion air and fluidizing air which passes through an air space so that fluidizing air is discharged into the reaction chamber fluidized bed at the bottom thereof to maintain the bed in a fluidized condition. A fluid, such as air, is passed through the tubes which extend through the windbox and provide a preheating of the combustion air and into an annular space between telescoped inner and outer tubes which comprise heat exchanger tubes or cooling tubes which extend upwardly through the distributor plate into the fluidized bed. The heat exchanger tubes are advantageously arranged so that they may be exposed in groups within the reactor in a cluster which is arranged within holding rings.

  17. Controlled Thermal-Mechanical Processing of Tubes and Pipes for Enhanced Manufacturing and Performance

    SciTech Connect (OSTI)

    Kolarik, Robert V.

    2005-11-11T23:59:59.000Z

    The Alloy Steel Business of The Timken Company won an award for the controlled thermo-mechanical processing (CTMP) project and assembled a strong international public/private partnership to execute the project. The premise of the CTMP work was to combine Timken's product understanding with its process expertise and knowledge of metallurgical and deformation fundamentals developed during the project to build a predictive process design capability. The CTMP effort succeeded in delivering a pc-based capability in the tube optimization model, with a virtual pilot plant (VPP) feature to represent the desired tube making process to predict the resultant microstructure tailored for the desired application. Additional tasks included a system for direct, online measurement of grain size and demonstration of application of CTMP via robotically enhanced manufacturing.

  18. A model for universal time scale of vortex ring formation Kamran Mohseni

    E-Print Network [OSTI]

    Mohseni, Kamran

    and Applied Science, 104-44, California Institute of Technology, Pasadena, California 91125 Morteza Gharib Graduate Aeronautical Laboratory, California Institute of Technology, Pasadena, California 91125 Received of the fluid out of the cylinder and the approximation of the vortex at the pinch off moment by a vortex

  19. Combustion in Meso-scale Vortex Chambers Ming-hsun Wu*

    E-Print Network [OSTI]

    Yang, Vigor

    1 Combustion in Meso-scale Vortex Chambers Ming-hsun Wu* , Yanxing Wang, Vigor Yang and Richard A) #12;2 COMBUSTION IN MESO-SCALE VORTEX CHAMBERS Ming-hsun Wu, Yanxing Wang, Vigor Yang and Richard A with the chemical energy varying from 25 to 174W. For the largest combustion volume, hydrogen and hydrocarbons

  20. The geometric phase and the geometrodynamics of relativistic electron vortex beams

    E-Print Network [OSTI]

    Pratul Bandyopadhyay; Banasri Basu; Debashree Chowdhury

    2013-11-28T23:59:59.000Z

    We have studied here the geometrodynamics of relativistic electron vortex beams from the perspective of the geometric phase associated with the scalar electron encircling the vortex line. It is pointed out that the electron vortex beam carrying orbital angular momentum is a natural consequence of the skyrmion model of a fermion. This follows from the quantization procedure of a fermion in the framework of Nelson's stochastic mechanics when a direction vector (vortex line) is introduced to depict the spin degrees of freedom. In this formalism a fermion is depicted as a scalar particle encircling a vortex line. It is here shown that when the Berry phase acquired by the scalar electron encircling the vortex line involves quantized Dirac monopole we have paraxial (non-paraxial) beam when the vortex line is parallel (orthogonal) to the wavefront propagation direction. Non-paraxial beams incorporate spin-orbit interaction. When the vortex line is tilted with respect to the propagation direction the Berry phase involves non-quantized monopole. The temporal variation of the direction of the tilted vortices is studied here taking into account the renormalization group flow of the monopole charge and it is predicted that this gives rise to spin Hall effect.

  1. Determination of magnetic vortex chirality using lateral spin-valve and Y. Otani

    E-Print Network [OSTI]

    Otani, Yoshichika

    Determination of magnetic vortex chirality using lateral spin-valve geometry T. Kimuraa and Y October 2005 We demonstrate the determination of the vortex chirality using a nonlocal spin-valve measurement technique in a lateral spin valve consisting of a Permalloy Py disk 1 m in diameter and a Py wire

  2. PHYSICAL REVIEW B 84, 144511 (2011) Rectification of vortex motion in a circular ratchet channel

    E-Print Network [OSTI]

    Plourde, Britton L. T.

    2011-01-01T23:59:59.000Z

    PHYSICAL REVIEW B 84, 144511 (2011) Rectification of vortex motion in a circular ratchet channel N and induces a net vortex flow without any unbiased external drive, i.e., the ratchet effect. We show containing a single weak-pinning circular ratchet channel in a Corbino geometry and observed a substantial

  3. Generalized London free energy for high-Tc vortex lattices Ian Affleck

    E-Print Network [OSTI]

    Franz, Marcel

    Generalized London free energy for high-Tc vortex lattices Ian Affleck Department of Physics-1829 97 50402-4 The London free energy provides a very simple way of studying the vortex lattice that this effect can arise from additional quartic derivative terms in the Ginzburg-Landau GL free energy4­7 or

  4. FABRICATION ET TUDE D'UN MONOCRISTAL DE VORTEX DANS LE NIOBIUM SUPRACONDUCTEUR

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    447 FABRICATION ET ÉTUDE D'UN MONOCRISTAL DE VORTEX DANS LE NIOBIUM SUPRACONDUCTEUR P. THOREL. 2014 Nous étudions expérimentalement par diffraction de neutrons le réseau de vortex dans le niobium ce V-cristal est liée à celle des axes cristallins du niobium, étant donné la forte anisotropie des

  5. GPU accelerated simulations of bluff body flows using vortex particle methods

    E-Print Network [OSTI]

    Cottet, Georges-Henri

    GPU accelerated simulations of bluff body flows using vortex particle methods Diego Rossinelli in press as: D. Rossinelli et al., GPU accelerated simulations of bluff body flows using vortex particle Penalization Bluff body flows a b s t r a c t We present a GPU accelerated solver for simulations of bluff body

  6. Lateral imaging of the superconducting vortex lattice using Doppler-modulated scanning tunneling microscopy

    E-Print Network [OSTI]

    Wei, John Y.T.

    Lateral imaging of the superconducting vortex lattice using Doppler-modulated scanning tunneling on the quasiparticle tunneling spectrum, we have laterally imaged the vortex lattice in superconducting 2H-NbSe2 that circulates along the sample edge. Above the lower critical field, field can penetrate into the superconductor

  7. Zero modes in vortex-fermion system with compact extra space

    E-Print Network [OSTI]

    A. Nakamula; K. Shiraishi

    2014-10-28T23:59:59.000Z

    The existence of fermionic zero modes is shown in the presence of vortex configuration of pure $SU(2)$ gauge field on the manifold $M_4 \\times S^2$. From the perspective of four-dimensional effective theory, these zero modes are almost the same as the Jackiw-Rossi type zero modes of the vortex-fermion system.

  8. Efficiently computing vortex lattices in fast rotating Bose-Einstein condensates Yanzhi Zhang1,2

    E-Print Network [OSTI]

    Bao, Weizhu

    Efficiently computing vortex lattices in fast rotating Bose-Einstein condensates Yanzhi Zhang1-Einstein condensates (BECs) with strongly repulsive interactions. The key ingredients of the method is to discretize method in time. Different vortex lattice structures of condensate ground state in two-dimensional (2D

  9. Progress in year 2001 1. Observation of Vortex Lattices in Bose-Einstein Condensates

    E-Print Network [OSTI]

    1 Progress in year 2001 1. Observation of Vortex Lattices in Bose-Einstein Condensates Quantized in rotating gaseous Bose-Einstein condensates (BEC) [2, 3]. We have observed the formation of highly-ordered vortex lattices in a rotating Bose- condensed gas [4]. They were produced by rotating the condensate

  10. Influence of slip on vortex-induced motion of a superhydrophobic cylinder

    E-Print Network [OSTI]

    Rothstein, Jonathan

    Influence of slip on vortex-induced motion of a superhydrophobic cylinder Robert Daniello, Pranesh: Superhydrophobic Ultrahydrophobic Superhydrophobicity Slip Partial slip Drag reduction Vortex Cylinder a b s t r a c t The partial slip boundary condition produced by a superhydrophobic surface in the Cassie state

  11. Elliptical-inertial instability of rotating Karman vortex streets A. Stegnera

    E-Print Network [OSTI]

    Stegner Alexandre

    Elliptical-inertial instability of rotating Karman vortex streets A. Stegnera Laboratoire de. Unlike the classical bidimensional Karman street, these observed vortex streets are affected by the earth Karman streets. A series of experiments were performed to study the wake of a cylinder in a rotating deep

  12. Vortex ratchet effects in films with a periodic array of antidots Clcio C. de Souza Silva,1,

    E-Print Network [OSTI]

    Moshchalkov, Victor V.

    Vortex ratchet effects in films with a periodic array of antidots Clécio C. de Souza Silva,1, * J The vortex ratchet effect has been studied in Al films patterned with square arrays of submicron antidots. We. In addition, the experiments reveal interesting collective phenomena in the vortex ratchet effect. At fields

  13. American Institute of Aeronautics and Astronautics A Numerical Study of Vortex-Dominated Flow around an Oscillating

    E-Print Network [OSTI]

    Hu, Hui

    flapping motion is due to the reverse von Karman vortex street. Recently, Bohl and Koochesfahani1 haveAmerican Institute of Aeronautics and Astronautics 1 A Numerical Study of Vortex-Dominated Flow at the Reynolds (Re) number of 12600. The effects of the reduced frequency and Strouhal number on the wake vortex

  14. Bluff Body Flow Simulation Using a Vortex Element Method

    SciTech Connect (OSTI)

    Anthony Leonard; Phillippe Chatelain; Michael Rebel

    2004-09-30T23:59:59.000Z

    Heavy ground vehicles, especially those involved in long-haul freight transportation, consume a significant part of our nation's energy supply. it is therefore of utmost importance to improve their efficiency, both to reduce emissions and to decrease reliance on imported oil. At highway speeds, more than half of the power consumed by a typical semi truck goes into overcoming aerodynamic drag, a fraction which increases with speed and crosswind. Thanks to better tools and increased awareness, recent years have seen substantial aerodynamic improvements by the truck industry, such as tractor/trailer height matching, radiator area reduction, and swept fairings. However, there remains substantial room for improvement as understanding of turbulent fluid dynamics grows. The group's research effort focused on vortex particle methods, a novel approach for computational fluid dynamics (CFD). Where common CFD methods solve or model the Navier-Stokes equations on a grid which stretches from the truck surface outward, vortex particle methods solve the vorticity equation on a Lagrangian basis of smooth particles and do not require a grid. They worked to advance the state of the art in vortex particle methods, improving their ability to handle the complicated, high Reynolds number flow around heavy vehicles. Specific challenges that they have addressed include finding strategies to accurate capture vorticity generation and resultant forces at the truck wall, handling the aerodynamics of spinning bodies such as tires, application of the method to the GTS model, computation time reduction through improved integration methods, a closest point transform for particle method in complex geometrics, and work on large eddy simulation (LES) turbulence modeling.

  15. Vortex nozzle for segmenting and transporting metal chips from turning operations

    DOE Patents [OSTI]

    Bieg, L.F.

    1993-04-20T23:59:59.000Z

    Apparatus for collecting, segmenting and conveying metal chips from machining operations utilizes a compressed gas driven vortex nozzle for receiving the chip and twisting it to cause the chip to segment through the application of torsional forces to the chip. The vortex nozzle is open ended and generally tubular in shape with a converging inlet end, a constant diameter throat section and a diverging exhaust end. Compressed gas is discharged through angled vortex ports in the nozzle throat section to create vortex flow in the nozzle and through an annular inlet at the entrance to the converging inlet end to create suction at the nozzle inlet and cause ambient air to enter the nozzle. The vortex flow in the nozzle causes the metal chip to segment and the segments thus formed to pass out of the discharge end of the nozzle where they are collected, cleaned and compacted as needed.

  16. Magnetic Vortex Core Reversal by Low-Field Excitations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9November 6, InaprilU .Magnetic Vortex Core

  17. Magnetic Vortex Core Reversal by Low-Field Excitations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9November 6, InaprilU .Magnetic Vortex CoreMagnetic

  18. Magnetic Vortex Core Reversal by Low-Field Excitations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9November 6, InaprilU .Magnetic Vortex

  19. Magnetic Vortex Core Reversal by Low-Field Excitations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9November 6, InaprilU .Magnetic VortexMagnetic

  20. Magnetic Vortex Core Reversal by Low-Field Excitations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9November 6, InaprilU .MagneticMagnetic Vortex Core

  1. Magnetic Vortex Core Reversal by Low-Field Excitations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |IsLove Your Home and It'll Love YouTokamak| NationalMagnetic Vortex

  2. Project Year Project Title

    E-Print Network [OSTI]

    Gray, Jeffrey J.

    Project Year 2011-2012 Project Title Using M-Health and GIS Technology in the Field to Improve-specialized, but practically useless skill. Solution One goal of this summer's Applied Geographic Information Systems in Public lessons about observational epidemiology. Technologies Used Geographic Info System (GIS), Blackboard

  3. The Relation Between Dry Vortex Merger and Tropical Cyclone Genesis over the Atlantic Ocean

    SciTech Connect (OSTI)

    Chen, Shu-Hua; Liu, Yi-Chin

    2014-10-27T23:59:59.000Z

    A strong, convective African tropical disturbance has a greater chance to develop into a Tropical 23 Depression (TD) if it merges with a shallow, dry vortex (D-vortex) from the north of the African 24 easterly jet (AEJ) after leaving the western coast. Using 11-year reanalysis data we found that the 25 western tip of a vortex strip at northwestern Africa can serve as dry vortices for the D-vortex 26 merger if it shifts southward. Another source of D-vortices is the westward propagating lows 27 along the southern edge of the Saharan air. The D-vortex merger process occurred for 63.5% of 28 tropical cyclones (TCs) or developing systems over the main development region of the Atlantic 29 Ocean, while it occurred for 54% of non-developing systems. TC genesis could be largely 30 controlled by the large-scale environment, but the differences in characteristics of vortices 31 associated with the D-vortex merger between developing and non-developing systems could 32 potentially help determine their destinies; in general, developing systems were dominated by a 33 more intense and moist south vortex, while non-developing systems were dominated by a north 34 vortex which was more intense, drier, and larger in size. Analysis also shows that 74% of intense 35 developing systems were involved with the D-vortex merger process. More attention needs to be 36 paid to the D-vortex merger and the characteristics of those vortices as they can play significant 37 roles or have a strong indication in Atlantic TC genesis.

  4. Particle seeding flow system for horizontal shock tube

    SciTech Connect (OSTI)

    Johnston, Stephen [Los Alamos National Laboratory; Garcia, Nicolas J. [Los Alamos National Laboratory; Martinez, Adam A. [Los Alamos National Laboratory; Orlicz, Gregory C. [Los Alamos National Laboratory; Prestridge, Katherine P. [Los Alamos National Laboratory

    2012-08-01T23:59:59.000Z

    The Extreme Fluids Team in P-23, Physics Division, studies fluid dynamics at high speeds using high resolution diagnostics. The unsteady forces on a particle driven by a shock wave are not well understood, and they are difficult to model. A horizontal shock tube (HST) is being modified to collect data about the behavior of particles accelerated by shocks. The HST has been used previously for studies of Richtmyer-Meshkov instability using Planar Laser-Induced Fluorescence (PLIF) as well as Particle Image Velocimetry (PIV), diagnostics that measure density and velocity. The purpose of our project is to design a flow system that will introduce particles into the HST. The requirements for this particle flow system (PFS) are that it be non-intrusive, be able to introduce either solid or liquid particles, have an exhaust capability, not interfere with existing diagnostics, and couple with the existing HST components. In addition, the particles must flow through the tube in a uniform way. We met these design criteria by first drawing the existing shock tube and diagnostics and doing an initial design of the ducts for the PFS. We then estimated the losses through the particle flow system from friction and researched possible fans that could be used to drive the particles. Finally, the most challenging component of the design was the coupling to the HST. If we used large inlets, the shock would lose strength as it passed by the inlet, so we designed a novel coupling inlet and outlet that minimize the losses to the shock wave. Our design was reviewed by the Extreme Fluids Team, and it is now being manufactured and built based upon our technical drawings.

  5. Automated Diagnosis and Classification of Steam Generator Tube Defects

    SciTech Connect (OSTI)

    Dr. Gabe V. Garcia

    2004-10-01T23:59:59.000Z

    A major cause of failure in nuclear steam generators is tube degradation. Tube defects are divided into seven categories, one of which is intergranular attack/stress corrosion cracking (IGA/SCC). Defects of this type usually begin on the outer surface of the tubes and propagate both inward and laterally. In many cases these defects occur at or near the tube support plates. Several different methods exist for the nondestructive evaluation of nuclear steam generator tubes for defect characterization.

  6. Design and evaluate finned tube bundles

    SciTech Connect (OSTI)

    Ganapathy, V. [ABCO Industries, Abilene, TX (United States)

    1996-09-01T23:59:59.000Z

    Finned tube bundles are widely used in heat exchangers, air coolers, waste heat boilers and fired heaters where energy transfer occurs between clean flue gases and a fluid with a high heat-transfer coefficient. They have several advantages including compactness, low gas pressure drop and low weight for a given duty compared to bare tube bundles. Choosing a fin type, arrangement and fin configuration requires a thorough analysis and economic evaluation. The solution is not unique since it depends on material and labor costs. Surface areas vary widely in finned tube designs for the same duty and gas pressure drop. Therefore, decisions should not be based on surface area alone. Plant engineers and consultants should consider operating costs in their evaluation because they accrue year after year. Selecting a boiler based on initial costs alone is not prudent. The paper discusses heat transfer and gas pressure drop with finned tubes, determining fin efficiency and effectiveness,g as pressure drop, tube wall and fin top temperatures, an example calculation, the effect of fin configuration on design, the effect of inline versus staggered arrangements and solid versus serrated fins, and concerns with high fin-density designs.

  7. The STACEE Project

    E-Print Network [OSTI]

    Ong, R A; Ong, Rene A.; Covault, Corbin E.

    1997-01-01T23:59:59.000Z

    The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is a telescope designed to explore the gamma-ray sky between 20 and 250 GeV using the atmospheric Cherenkov technique. STACEE is currently under construction. When completed, it will use 48 large heliostat mirrors at the solar research facility at Sandia National Laboratories (Albuquerque, NM) to reflect Cherenkov light created in gamma-ray air showers to secondary mirrors on a central tower. The secondary mirrors image this light onto photomultiplier tube cameras. This paper provides an overview of the STACEE project, including a description of the experimental site and an outline of the current design for the detector components.

  8. The STACEE Project

    E-Print Network [OSTI]

    Rene A. Ong; Corbin E. Covault

    1997-11-25T23:59:59.000Z

    The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is a telescope designed to explore the gamma-ray sky between 20 and 250 GeV using the atmospheric Cherenkov technique. STACEE is currently under construction. When completed, it will use 48 large heliostat mirrors at the solar research facility at Sandia National Laboratories (Albuquerque, NM) to reflect Cherenkov light created in gamma-ray air showers to secondary mirrors on a central tower. The secondary mirrors image this light onto photomultiplier tube cameras. This paper provides an overview of the STACEE project, including a description of the experimental site and an outline of the current design for the detector components.

  9. Project Fact Sheet Project Update

    E-Print Network [OSTI]

    & Figures: Budget: £51,074,000 Funding Source: Capital Plan Construction Project Programme: Start on SiteProject Fact Sheet Project Update: Project Brief: The concept of the new scheme is to redevelop Gardens project http://www.imperial.ac.uk/princesgardens/ Construction Project Team: Project Facts

  10. The U-tube sampling methodology and real-time analysis of geofluids

    SciTech Connect (OSTI)

    Freifeld, Barry; Perkins, Ernie; Underschultz, James; Boreham, Chris

    2009-03-01T23:59:59.000Z

    The U-tube geochemical sampling methodology, an extension of the porous cup technique proposed by Wood [1973], provides minimally contaminated aliquots of multiphase fluids from deep reservoirs and allows for accurate determination of dissolved gas composition. The initial deployment of the U-tube during the Frio Brine Pilot CO{sub 2} storage experiment, Liberty County, Texas, obtained representative samples of brine and supercritical CO{sub 2} from a depth of 1.5 km. A quadrupole mass spectrometer provided real-time analysis of dissolved gas composition. Since the initial demonstration, the U-tube has been deployed for (1) sampling of fluids down gradient of the proposed Yucca Mountain High-Level Waste Repository, Armagosa Valley, Nevada (2) acquiring fluid samples beneath permafrost in Nunuvut Territory, Canada, and (3) at a CO{sub 2} storage demonstration project within a depleted gas reservoir, Otway Basin, Victoria, Australia. The addition of in-line high-pressure pH and EC sensors allows for continuous monitoring of fluid during sample collection. Difficulties have arisen during U-tube sampling, such as blockage of sample lines from naturally occurring waxes or from freezing conditions; however, workarounds such as solvent flushing or heating have been used to address these problems. The U-tube methodology has proven to be robust, and with careful consideration of the constraints and limitations, can provide high quality geochemical samples.

  11. Alternate Materials for Recovery Boiler Superheater Tubes

    SciTech Connect (OSTI)

    Keiser, James R [ORNL; Kish, Joseph [McMaster University; Singbeil, Douglas [FPInnovations

    2009-01-01T23:59:59.000Z

    The ever escalating demands for increased efficiency of all types of boilers would most sensibly be realized by an increase in the steam parameters of temperature and pressure. However, materials and corrosion limitations in the steam generating components, particularly the superheater tubes, present major obstacles to boiler designers in achieving systems that can operate under the more severe conditions. This paper will address the issues associated with superheater tube selection for many types of boilers; particularly chemical recovery boilers, but also addressing the similarities in issues for biomass and coal fired boilers. It will also review our recent study of materials for recovery boiler superheaters. Additional, more extensive studies, both laboratory and field, are needed to gain a better understanding of the variables that affect superheater tube corrosion and to better determine the best means to control this corrosion to ultimately permit operation of recovery boilers at higher temperatures and pressures.

  12. Circumferential cracking of steam generator tubes

    SciTech Connect (OSTI)

    Karwoski, K.J.

    1997-04-01T23:59:59.000Z

    On April 28, 1995, the U.S. Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 95-03, {open_quote}Circumferential Cracking of Steam Generator Tubes.{close_quote} GL 95-03 was issued to obtain information needed to verify licensee compliance with existing regulatory requirements regarding the integrity of steam generator tubes in domestic pressurized-water reactors (PWRs). This report briefly describes the design and function of domestic steam generators and summarizes the staff`s assessment of the responses to GL 95-03. The report concludes with several observations related to steam generator operating experience. This report is intended to be representative of significant operating experience pertaining to circumferential cracking of steam generator tubes from April 1995 through December 1996. Operating experience prior to April 1995 is discussed throughout the report, as necessary, for completeness.

  13. Zero dead volume tube to surface seal

    DOE Patents [OSTI]

    Benett, William J. (Livermore, CA); Folta, James A. (Livermore, CA)

    2000-01-01T23:59:59.000Z

    A method and apparatus for connecting a tube to a surface that creates a dead volume seal. The apparatus is composed of three components, a body, a ferrule, and a threaded fitting. The ferrule is compressed onto a tube and a seal is formed between the tube and a device retained in the body by threading the fitting into the body which provides pressure that seals the face of the ferrule to a mating surface on the device. This seal can be used at elevated temperatures depending on the materials used. While the invention has been developed for use with micro-machined silicon wafers used in Capillary Gas Chromatograph (GC), it can be utilized anywhere for making a gas or fluid face seal to the surface of a device that has near zero dead volume.

  14. Project Funding

    Broader source: Energy.gov [DOE]

    Federal energy projects require funding to generate results. Carefully matching available funding options with specific project needs can make the difference between a stalled, unfunded project and a successful project generating energy and cost savings.

  15. Pulse tube coolers for Meteosat third generation

    SciTech Connect (OSTI)

    Butterworth, James; Aigouy, Gérald; Chassaing, Clement; Debray, Benoît; Huguet, Alexandre [Air Liquide Advanced Technologies, 2 Rue de Clémencière, F-38600 Sassenage (France)

    2014-01-29T23:59:59.000Z

    Air Liquide's Large Pulse Tube Coolers (LPTC) will be used to cool the focal planes of the Infrared Sounder (IRS) and Flexible Combined Imager (FCI) instruments aboard the ESA/Eumetsat satellites Meteosat Third Generation (MTG). This cooler consists of an opposed piston linear compressor driving a pulse tube cold head and the associated drive electronics including temperature regulation and vibration cancellation algorithms. Preparations for flight qualification of the cooler are now underway. In this paper we present results of the optimization and qualification activities as well as an update on endurance testing.

  16. Field Demonstraton of Existing Microhole Coiled Tubing Rig (MCTR) Technology

    SciTech Connect (OSTI)

    Kent Perry; Samih Batarseh; Sheriff Gowelly; Thomas Hayes

    2006-05-09T23:59:59.000Z

    The performance of an advanced Microhole Coiled Tubing Rig (MCTR) has been measured in the field during the drilling of 25 test wells in the Niobrara formation of Western Kansas and Eastern Colorado. The coiled tubing (CT) rig designed, built and operated by Advanced Drilling Technologies (ADT), was documented in its performance by GTI staff in the course of drilling wells ranging in depth from 500 to nearly 3,000 feet. Access to well sites in the Niobrara for documenting CT rig performance was provided by Rosewood Resources of Arlington, VA. The ADT CT rig was selected for field performance evaluation because it is one of the most advanced commercial CT rig designs that demonstrate a high degree of process integration and ease of set-up and operation. Employing an information collection protocol, data was collected from the ADT CT rig during 25 drilling events that encompassed a wide range of depths and drilling conditions in the Niobrara. Information collected included time-function data, selected parametric information indicating CT rig operational conditions, staffing levels, and field observations of the CT rig in each phase of operation, from rig up to rig down. The data obtained in this field evaluation indicates that the ADT CT rig exhibited excellent performance in the drilling and completion of more than 25 wells in the Niobrara under varied drilling depths and formation conditions. In the majority of the 25 project well drilling events, ROP values ranged between 300 and 620 feet per hour. For all but the lowest 2 wells, ROP values averaged approximately 400 feet per hour, representing an excellent drilling capability. Most wells of depths between 500 and 2,000 feet were drilled at a total functional rig time of less than 16 hours; for wells as deep at 2,500 to 3,000 feet, the total rig time for the CT unit is usually well under one day. About 40-55 percent of the functional rig time is divided evenly between drilling and casing/cementing. The balance of time is divided among the remaining four functions of rig up/rig down, logging, lay down bottomhole assembly, and pick up bottomhole assembly. Observations made during all phases of CT rig operation at each of the project well installations have verified a number of characteristics of the technology that represent advantages that can produce significant savings of 25-35 percent per well. Attributes of the CT rig performance include: (1) Excellent hole quality with hole deviation amounting to 1-2 degrees; (2) Reduced need for auxiliary equipment; (3) Efficient rig mobilization requiring only four trailers; (4) Capability of ''Zero Discharge'' operation; (5) Improved safety; and, (6) Measurement while drilling capability. In addition, commercial cost data indicates that the CT rig reduces drilling costs by 25 to 35% compared to conventional drilling technology. Widespread commercial use of the Microhole Coiled Tubing technology in the United States for onshore Lower-48 drilling has the potential of achieving substantially positive impacts in terms of savings to the industry and resource expansion. Successfully commercialized Microhole CT Rig Technology is projected to achieve cumulative savings in Lower-48 onshore drilling expenditures of approximately 6.8 billion dollars by 2025. The reduced cost of CT microhole drilling is projected to enable the development of gas resources that would not have been economic with conventional methods. Because of the reduced cost of drilling achieved with CT rig technology, it is estimated that an additional 22 Tcf of gas resource will become economic to develop. In the future, the Microhole Coiled Tubing Rig represents an important platform for the continued improvement of drilling that draws on a new generation of various technologies to achieve goals of improved drilling cost and reduced impact to the environment.

  17. Microhole High-Pressure Jet Drill for Coiled Tubing

    SciTech Connect (OSTI)

    Ken Theimer; Jack Kolle

    2007-06-30T23:59:59.000Z

    Tempress Small Mechanically-Assisted High-Pressure Waterjet Drilling Tool project centered on the development of a downhole intensifier (DHI) to boost the hydraulic pressure available from conventional coiled tubing to the level required for high-pressure jet erosion of rock. We reviewed two techniques for implementing this technology (1) pure high-pressure jet drilling and (2) mechanically-assisted jet drilling. Due to the difficulties associated with modifying a downhole motor for mechanically-assisted jet drilling, it was determined that the pure high-pressure jet drilling tool was the best candidate for development and commercialization. It was also determined that this tool needs to run on commingled nitrogen and water to provide adequate downhole differential pressure and to facilitate controlled pressure drilling and descaling applications in low pressure wells. The resulting Microhole jet drilling bottomhole assembly (BHA) drills a 3.625-inch diameter hole with 2-inch coil tubing. The BHA consists of a self-rotating multi-nozzle drilling head, a high-pressure rotary seal/bearing section, an intensifier and a gas separator. Commingled nitrogen and water are separated into two streams in the gas separator. The water stream is pressurized to 3 times the inlet pressure by the downhole intensifier and discharged through nozzles in the drilling head. The energy in the gas-rich stream is used to power the intensifier. Gas-rich exhaust from the intensifier is conducted to the nozzle head where it is used to shroud the jets, increasing their effective range. The prototype BHA was tested at operational pressures and flows in a test chamber and on the end of conventional coiled tubing in a test well. During instrumented runs at downhole conditions, the BHA developed downhole differential pressures of 74 MPa (11,000 psi, median) and 90 MPa (13,000 psi, peaks). The median output differential pressure was nearly 3 times the input differential pressure available from the coiled tubing. In a chamber test, the BHA delivered up to 50 kW (67 hhp) hydraulic power. The tool drilled uncertified class-G cement samples cast into casing at a rate of 0.04 to 0.17 m/min (8 to 33 ft/hr), within the range projected for this tool but slower than a conventional PDM. While the tool met most of the performance goals, reliability requires further improvement. It will be difficult for this tool, as currently configured, to compete with conventional positive displacement downhole motors for most coil tubing drill applications. Mechanical cutters on the rotating nozzle head would improve cutting. This tool can be easily adapted for well descaling operations. A variant of the Microhole jet drilling gas separator was further developed for use with positive displacement downhole motors (PDM) operating on commingled nitrogen and water. A fit-for-purpose motor gas separator was designed and yard tested within the Microhole program. Four commercial units of that design are currently involved in a 10-well field demonstration with Baker Oil Tools in Wyoming. Initial results indicate that the motor gas separators provide significant benefit.

  18. Magnetic response of holographic Lifshitz superconductors:Vortex and Droplet solutions

    E-Print Network [OSTI]

    Arindam Lala

    2014-07-04T23:59:59.000Z

    In this paper a holographic model of $s$-wave superconductor with anisotropic Lifshitz scaling has been considered. In the presence of an external magnetic field our holographic model exhibits both vortex and droplet solutions. Based on analytic methods we have shown that the anisotropy has no effect on the vortex and droplet solutions whereas it may affect the condensation. Our vortex solution closely resembles the Ginzburg-Landau theory and a relation between the upper critical magnetic field and superconducting coherence length has been speculated from this comparison. Using Sturm-Liouville method, the effect of anisotropy on the critical parameters in insulator/superconductor phase transitions has been analyzed.

  19. Digital radiographic systems detect boiler tube cracks

    SciTech Connect (OSTI)

    Walker, S. [EPRI, Charlotte, NC (United States)

    2008-06-15T23:59:59.000Z

    Boiler water wall leaks have been a major cause of steam plant forced outages. But conventional nondestructive evaluation techniques have a poor track record of detecting corrosion fatigue cracking on the inside surface of the cold side of waterwall tubing. EPRI is performing field trials of a prototype direct-digital radiographic system that promises to be a game changer. 8 figs.

  20. Wave guides: vacuum w/ tube of conductor

    E-Print Network [OSTI]

    Hart, Gus

    Wave guides: vacuum w/ tube of conductor boundary conditions for conductor Properties: non-transverse waves except TEM mode in coaxial cable speed normal modes (from Liouville problem) TE or TM TEM for coaxial cable cuto frequency otherwise evanescent waves separation into and components with 1 #12;B

  1. Composite Tube Trailer Design/Manufacturing Needs

    E-Print Network [OSTI]

    composite tube trailers and can, therefore, address issues with: ­ Design ­ Materials ­ Manufacturing in the system ­ Lower cost of carbon fiber ($/strength) ­ Identify material with lower net cost ($/strength) ­ Identify lower cost resin system (raw material & manufacture) ­ Reduce carbon fiber safety factor

  2. Energies of Quantum QED Flux Tubes

    E-Print Network [OSTI]

    H Weigel

    2006-01-26T23:59:59.000Z

    In this talk I present recent studies on vacuum polarization energies and energy densities induced by QED flux tubes. I focus on comparing three and four dimensional scenarios and the discussion of various approximation schemes in view of the exact treatment.

  3. "Fine grain Nb tube for SRF cavities"

    SciTech Connect (OSTI)

    Robert E. Barber

    2012-07-08T23:59:59.000Z

    Superconducting radio frequency (SRF) cavities used in charged particle linear accelerators, are currently fabricated by deep drawing niobium sheets and welding the drawn dishes together. The Nb sheet has a non-uniform microstructure, which leads to unpredictable cavity shape and surface roughness, and inconsistent "spring-back" during forming. In addition, weld zones cause hot spots during cavity operation. These factors limit linear accelerator performance and increase cavity manufacturing cost. Equal channel angular extrusion (ECAE) can be used to refine and homogenize the microstructure of Nb tube for subsequent hydroforming into SRF cavities. Careful selection of deformation and heat treatment conditions during the processing steps can give a uniform and consistent microstructure in the tube, leading to improved deformability and lower manufacturing costs. Favorable microstructures were achieved in short test samples of RRR Nb tube, which may be particularly suitable for hydroforming into SRF cavity strings. The approach demonstrated could be applicable to microstructure engineering of other tube materials including tantalum, titanium, and zirconium.

  4. Decay of helical Kelvin waves on a quantum vortex filament

    SciTech Connect (OSTI)

    Van Gorder, Robert A., E-mail: rav@knights.ucf.edu [Department of Mathematics, University of Central Florida, Orlando, Florida 32816-1364 (United States)

    2014-07-15T23:59:59.000Z

    We study the dynamics of helical Kelvin waves moving along a quantum vortex filament driven by a normal fluid flow. We employ the vector form of the quantum local induction approximation (LIA) due to Schwarz. For an isolated filament, this is an adequate approximation to the full Hall-Vinen-Bekarevich-Khalatnikov dynamics. The motion of such Kelvin waves is both translational (along the quantum vortex filament) and rotational (in the plane orthogonal to the reference axis). We first present an exact closed form solution for the motion of these Kelvin waves in the case of a constant amplitude helix. Such solutions exist for a critical wave number and correspond exactly to the Donnelly-Glaberson instability, so perturbations of such solutions either decay to line filaments or blow-up. This leads us to consider helical Kelvin waves which decay to line filaments. Unlike in the case of constant amplitude helical solutions, the dynamics are much more complicated for the decaying helical waves, owing to the fact that the rate of decay of the helical perturbations along the vortex filament is not constant in time. We give an analytical and numerical description of the motion of decaying helical Kelvin waves, from which we are able to ascertain the influence of the physical parameters on the decay, translational motion along the filament, and rotational motion, of these waves (all of which depend nonlinearly on time). One interesting finding is that the helical Kelvin waves do not decay uniformly. Rather, such waves decay slowly for small time scales, and more rapidly for large time scales. The rotational and translational velocity of the Kelvin waves depend strongly on this rate of decay, and we find that the speed of propagation of a helical Kelvin wave along a quantum filament is large for small time while the wave asymptotically slows as it decays. The rotational velocity of such Kelvin waves along the filament will increase over time, asymptotically reaching a finite value. These decaying Kelvin waves correspond to wave number below the critical value for the Donnelly-Glaberson instability, and hence our results on the Schwarz quantum LIA correspond exactly to what one would expect from prior work on the Donnelly-Glaberson instability.

  5. Math 13900 YouTube Quiz 2013 Find a video on YouTube that ...

    E-Print Network [OSTI]

    Roames, Renee S

    2013-01-02T23:59:59.000Z

    Find a video on YouTube that addresses the idea of symmetry – either for 2 dimensions or 3 as we have been studying in lessons 9 and 10. The video should be ...

  6. Gas turbine engine combustor can with trapped vortex cavity

    DOE Patents [OSTI]

    Burrus, David Louis; Joshi, Narendra Digamber; Haynes, Joel Meier; Feitelberg, Alan S.

    2005-10-04T23:59:59.000Z

    A gas turbine engine combustor can downstream of a pre-mixer has a pre-mixer flowpath therein and circumferentially spaced apart swirling vanes disposed across the pre-mixer flowpath. A primary fuel injector is positioned for injecting fuel into the pre-mixer flowpath. A combustion chamber surrounded by an annular combustor liner disposed in supply flow communication with the pre-mixer. An annular trapped dual vortex cavity located at an upstream end of the combustor liner is defined between an annular aft wall, an annular forward wall, and a circular radially outer wall formed therebetween. A cavity opening at a radially inner end of the cavity is spaced apart from the radially outer wall. Air injection first holes are disposed through the forward wall and air injection second holes are disposed through the aft wall. Fuel injection holes are disposed through at least one of the forward and aft walls.

  7. Vortex flow in the technology of radiation wave cracking (RWC)

    E-Print Network [OSTI]

    L. A. Tsoy; V. N. Kolushov; A. G. Komarov; A. N. Tsoy

    2012-09-16T23:59:59.000Z

    This article examines the theory of vortex flows in relation to the processes occurring in the radiation-wave cracking of crude oil, when the crude oil is sprayed into the gas stream in the form of a mist and then is fed into the reactor, where it is treated by the accelerated electrons and the UHF radiation. The output of this process are the products with the specified parameters (high-octane petroleum products). This process operates at the ambient pressure and temperature, which makes the process safer for industrial purposes. Besides the process itself, the authors described the equipment used in this process, as well as the parameters of the optimal process.

  8. Exact moduli space metrics for hyperbolic vortex polygons

    SciTech Connect (OSTI)

    Krusch, S. [School of Mathematics, Statistics and Actuarial Science, University of Kent, Canterbury CT2 7NF (United Kingdom); Speight, J. M. [Department of Pure Mathematics, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2010-02-15T23:59:59.000Z

    Exact metrics on some totally geodesic submanifolds of the moduli space of static hyperbolic N-vortices are derived. These submanifolds, denoted as {sigma}{sub n,m}, are spaces of C{sub n}-invariant vortex configurations with n single vortices at the vertices of a regular polygon and m=N-n coincident vortices at the polygon's center. The geometric properties of {sigma}{sub n,m} are investigated, and it is found that {sigma}{sub n,n-1} is isometric to the hyperbolic plane of curvature -(3{pi}n){sup -1}. The geodesic flow on {sigma}{sub n,m} and a geometrically natural variant of geodesic flow recently proposed by Collie and Tong ['The dynamics of Chern-Simons vortices', Phys. Rev. D Part. Fields Gravit. Cosmol. 78, 065013 (2008);e-print arXiv:hep-th/0805.0602] are analyzed in detail.

  9. Vortex and gap generation in gauge models of graphene

    E-Print Network [OSTI]

    O. Oliveira; C. E. Cordeiro; A. Delfino; W. de Paula; T. Frederico

    2011-04-22T23:59:59.000Z

    Effective quantum field theoretical continuum models for graphene are investigated. The models include a complex scalar field and a vector gauge field. Different gauge theories are considered and their gap patterns for the scalar, vector, and fermion excitations are investigated. Different gauge groups lead to different relations between the gaps, which can be used to experimentally distinguish the gauge theories. In this class of models the fermionic gap is a dynamic quantity. The finite-energy vortex solutions of the gauge models have the flux of the "magnetic field" quantized, making the Bohm-Aharonov effect active even when external electromagnetic fields are absent. The flux comes proportional to the scalar field angular momentum quantum number. The zero modes of the Dirac equation show that the gauge models considered here are compatible with fractionalization.

  10. Vortex life cycles in two-and three-layer quasi-geostrophic models 

    E-Print Network [OSTI]

    Fox, Amanda Katherine

    2000-01-01T23:59:59.000Z

    Coherent vortices and their properties were studied in two- and three-layer quasi-geostrophic beta-plane turbulence. Much research has discussed vortex characteristics in a number of applications, but no significant study of vortices in turbulent...

  11. On the vortex parameter estimation using wide band signals in active acoustic system

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    is an important operation in a large number of applications such as turbine monitoring, de- tection of a vortex in a closed hydraulic test loop. The objective of the work is to emphasize the effect

  12. Falling, flapping, flying, swimming,... : high-Re fluid-solid interactions with vortex shedding

    E-Print Network [OSTI]

    Michelin, Sébastien Honoré Roland

    2009-01-01T23:59:59.000Z

    Meckh. , 1, 79–86. Krasny, R. , 1986a: Desingularisation ofJ. Comp. Phys. , 65, 292–313. Krasny, R. , 1986b: A study ofvortex sheet equation (Krasny, 1986a,b). The vortex sheet

  13. Under consideration for publication in J. Fluid Mech. 1 Mixing in a vortex breakdown flow

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    & Kohlman 1971; Hall 1972; Lowson & Riley 1995) where it creates a sudden drop of the lift and an increase the core of the vortex. Artificial tornadoes within a chimney have been proposed as a way of converting

  14. The vortex merger rate in freely decaying, two-dimensional turbulence J. H. LaCascea

    E-Print Network [OSTI]

    LaCasce, Joseph H.

    vortex models in which energy-conserving mergers were allowed. Trizac19 used a molecular dynamics in laboratory experiments in which vortices were generated by electromagnetic excitation in an electrolyte.10

  15. A Model of Compressor Blade Row Interaction with Shock Induced Vortex Shedding

    E-Print Network [OSTI]

    Cincinnati, University of

    A Model of Compressor Blade Row Interaction with Shock Induced Vortex Shedding Mark G. Turner = circulation = trailing edge thickness = shock angle = density I. Introduction ransonic compressor stages AIAA. Research Scientist, Compressor Aerodynamic Research Laboratory, Associate Fellow AIAA

  16. Hierarchical Colloidal Vortex Rings in a Constant Electric Field Yilong Han and David G. Grier

    E-Print Network [OSTI]

    Grier, David

    15 1050 15 (b) (c) (d) (e) packed close- core vortex ring (d) (e)(b) (c) (a) (f) corona t [sec] Rg) tracking its radius of gyration Rg over time. spheres is surrounded by a diffuse circulating corona

  17. Hierarchical Colloidal Vortex Rings in a Constant Electric Field Yilong Han and David G. Grier

    E-Print Network [OSTI]

    Grier, David

    15 10 5 0 15 (b) (c) (d) (e) packed close- core vortex ring (d) (e) (b) (c) (a) (f) corona t [sec] Rg corona that extends outward for tens of micrometers. Although these clusters somewhat resemble

  18. Steady-state and equilibrium vortex configurations, transitions, and evolution in a mesoscopic superconducting cylinder

    E-Print Network [OSTI]

    Kim, S.; Hu, Chia-Ren; Andrews, MJ.

    2004-01-01T23:59:59.000Z

    that the system passes through nearly metastable intermediate configurations while seeking the final minimum-energy steady state consistent with the square symmetry of the sample. An efficient scheme to determine the equilibrium vortex configuration in a...

  19. Effect of traveling waves on Vortex-Induced Vibration of long flexible cylinders

    E-Print Network [OSTI]

    Jaiswal, Vivek, Ph. D. Massachusetts Institute of Technology

    2009-01-01T23:59:59.000Z

    Offshore marine risers and pipelines, exposed to ocean currents, are susceptible to Vortex-Induced Vibration (VIV). Accurate prediction of VIV is necessary for estimating the fatigue life as well as for taking corrective ...

  20. Interaction between magnetic vortex cores in a pair of nonidentical nanodisks

    SciTech Connect (OSTI)

    Sinnecker, J. P.; Vigo-Cotrina, H.; Garcia, F.; Novais, E. R. P.; Guimarães, A. P., E-mail: apguima@cbpf.br [Centro Brasileiro de Pesquisas Físicas, 22290-180, Rio de Janeiro, Rio de Janeiro (Brazil)

    2014-05-28T23:59:59.000Z

    The coupling of two nonidentical magnetic nanodisks, i.e., with different vortex gyrotropic frequencies, is studied. From the analytical approach, the interactions between the nanodisks along x and y directions (the coupling integrals) were obtained as a function of distance. From the numerical solution of Thiele's equation, we derived the eigenfrequencies of the vortex cores as a function of distance. The motion of the two vortex cores and, consequently, the time dependence of the total magnetization M(t) were derived both using Thiele's equation and by micromagnetic simulation. From M(t), a recently developed method, the magnetic vortex echoes, analogous to the Nuclear Magnetic Resonance spin echoes, was used to compute the distance dependence of the magnetic coupling strength. The results of the two approaches differ by approximately 10%; using one single term, a dependence with distance found is broadly in agreement with studies employing other techniques.

  1. Interacting vortex pairs in inviscid and viscous planar flows Thierry Gallay

    E-Print Network [OSTI]

    Gallay, Thierry

    Interacting vortex pairs in inviscid and viscous planar flows Thierry Gallay Universitâ??e de Grenoble I Institut Fourier, UMR CNRS 5582 B.P. 74 F­38402 Saint­Martin­d'Hâ??eres, France Thierry.Gallay

  2. Interacting vortex pairs in inviscid and viscous planar flows Thierry Gallay

    E-Print Network [OSTI]

    Gallay, Thierry

    Interacting vortex pairs in inviscid and viscous planar flows Thierry Gallay Universit´e de Grenoble I Institut Fourier, UMR CNRS 5582 B.P. 74 F-38402 Saint-Martin-d'H`eres, France Thierry.Gallay

  3. Vortex-induced vibration of marine risers : motion and force reconstruction from field and experimental data

    E-Print Network [OSTI]

    Mukundan, Harish

    2008-01-01T23:59:59.000Z

    Vortex-induced vibration (VIV) of long flexible cylindrical structures enduring ocean currents is ubiquitous in the offshore industry. Though significant effort has gone into understanding this complicated fluid-structure ...

  4. Vortex-induced vibration of flexible cylinders in time-varying flows

    E-Print Network [OSTI]

    Resvanis, Themistocles L

    2014-01-01T23:59:59.000Z

    This thesis investigates two aspects of Vortex-Induced Vibrations (VIV) on long flexible cylinders. The work is split into a minor and major part. The minor part addresses the effect of Reynolds number on flexible cylinder ...

  5. Vortex Induced Vibrations of cylinders : experiments in reducing drag force and amplitude of motion

    E-Print Network [OSTI]

    Farrell, David Emmanuel

    2007-01-01T23:59:59.000Z

    Reducing the deleterious effect of Vortex Induced Vibrations (VIV) in marine risers is an important task for ocean engineers; and many competing factors exist in the design of VIV suppression devices. This thesis explores ...

  6. Vortex-induced vibrations of a long flexible cylinder in shear flow

    E-Print Network [OSTI]

    Triantafyllou, Michael S.

    We investigate the in-line and cross-flow vortex-induced vibrations of a long cylindrical tensioned beam, with length to diameter ratio L/D = 200, placed within a linearly sheared oncoming flow, using three-dimensional ...

  7. Enhancement of vortex induced forces and motion through surface roughness control

    DOE Patents [OSTI]

    Bernitsas, Michael M. (Saline, MI); Raghavan, Kamaldev (Houston, TX)

    2011-11-01T23:59:59.000Z

    Roughness is added to the surface of a bluff body in a relative motion with respect to a fluid. The amount, size, and distribution of roughness on the body surface is controlled passively or actively to modify the flow around the body and subsequently the Vortex Induced Forces and Motion (VIFM). The added roughness, when designed and implemented appropriately, affects in a predetermined way the boundary layer, the separation of the boundary layer, the level of turbulence, the wake, the drag and lift forces, and consequently the Vortex Induced Motion (VIM), and the fluid-structure interaction. The goal of surface roughness control is to increase Vortex Induced Forces and Motion. Enhancement is needed in such applications as harnessing of clean and renewable energy from ocean/river currents using the ocean energy converter VIVACE (Vortex Induced Vibration for Aquatic Clean Energy).

  8. Insulated laser tube structure and method of making same

    DOE Patents [OSTI]

    Dittbenner, Gerald R. (4353 Findlay Way, Livermore, CA 94550)

    1999-01-01T23:59:59.000Z

    An insulated high temperature ceramic laser tube having substantially uniform insulation along the length of the tube is disclosed having particulate ceramic insulation positioned between the outer wall of the ceramic laser tube and the inner surface of tubular ceramic fiber insulation which surrounds the ceramic laser tube. The particulate ceramic insulation is preferably a ceramic capable of sintering to the outer surface of the ceramic laser tube and to the inner surface of the tubular ceramic fiber insulation. The addition of the particulate ceramic insulation to fill all the voids between the ceramic laser tube and the fibrous ceramic insulation permits the laser tube to be operated at a substantially uniform temperature throughout the length of the laser tube.

  9. Refrigerant forced-convection condensation inside horizontal tubes

    E-Print Network [OSTI]

    Bae, Soonhoon

    1968-01-01T23:59:59.000Z

    Condensing heat transfer rates inside a horizontal tube were investigated -for large quality changes across the tube. The proposed correlation is a modification of the work of Rohsenow, Webber and Ling [29]. The result of ...

  10. Fouling of HVAC fin and tube heat exchangers

    E-Print Network [OSTI]

    Siegel, Jeffrey; Carey, Van P.

    2001-01-01T23:59:59.000Z

    air ? air ? part ? part FPI HVAC REFERENCES Anonymous, 1987,LBNL-47668 Fouling of HVAC Fin and Tube Heat ExchangersCIEE SPONSOR. FOULING OF HVAC FIN AND TUBE HEAT EXCHANGERS

  11. Nonlinear axisymmetric deformations of an elastic tube under external pressure

    E-Print Network [OSTI]

    Luo, Xiaoyu

    tube subject to pressure on its external lateral boundaries and zero displacement on its ends) performed a numerical simulation of the post-buckling behaviour of tubes under external pressure

  12. Vortex in a weakly relativistic Bose gas at zero temperature and relativistic fluid approximation

    E-Print Network [OSTI]

    B. Boisseau

    2004-09-14T23:59:59.000Z

    The Bogoliubov procedure in quantum field theory is used to describe a relativistic almost ideal Bose gas at zero temperature. Special attention is given to the study of a vortex. The radius of the vortex in the field description is compared to that obtained in the relativistic fluid approximation. The Kelvin waves are studied and, for long wavelengths, the dispersion relation is obtained by an asymptotic matching method and compared with the non relativistic result.

  13. Department of Mechanical Engineering RESEARCH PROJECT

    E-Print Network [OSTI]

    Barthelat, Francois

    and aircraft engines PROJECTS · Non-catalytic reformation of fuels to hydrogen for fuel cell vehicles · Combustion properties of biofuels, including biodiesel and biojet fuels · Shock tube ignition experiments and flame studies using laser diagnostics LABORATORY · Macdonald Engineering 257, 051 Prof. Jeff Bergthorson

  14. Project Title:

    Broader source: Energy.gov (indexed) [DOE]

    Repair flowline 61-66-SX-3 DOE Code: Project Lead: Wes Riesland NEPA COMPLIANCE SURVEY 291 Project Information Date: 31 12010 Contractor Code: Project Overview In order to...

  15. Heat transfer of finned tube bundles in crossflow

    SciTech Connect (OSTI)

    Stasiulevicius, J.; Skrinska, A.; Zukauskas, A.

    1988-01-01T23:59:59.000Z

    This volume correlates findings on heat transfer and hydraulic drag of bundles of finned tubes in crossflow at Reynolds numbers from 10/sup 4/ to 10/sup 6/. These studies illustrate fin, local, and mean heat transfer coefficients; effects of geometric parameters of the fins; effect of tube location within the bundle on heat transfer and hydraulic drag; and resistance of finned tube bundles.

  16. Iterative Learning Control Applications to High Power Microwave Tubes

    E-Print Network [OSTI]

    day high-peak power microwave (HPM) sources typically operate in the * *single shot regime because commercial HPM systems that operate at modest repetition rates, two examples of* * which include a system the control algorithms on a * *physical tube in order to build a "smart tube" HPM source. By smart tube we

  17. The universal criterion for switching a magnetic vortex core in soft magnetic nanodots

    SciTech Connect (OSTI)

    Lee, K.-S.; Kim, S.-K.; Yu, Y.-S.; Choi, Y.-S.; Guslienko, K. Y.; Jung, H.; Fischer, P.

    2008-10-01T23:59:59.000Z

    The universal criterion for ultrafast vortex core switching between core-up and -down vortex bi-states in soft magnetic nanodots was empirically investigated by micromagnetic simulations and combined with an analytical approach. Vortex-core switching occurs whenever the velocity of vortex core motion reaches a critical value, which is {nu}{sub c} = 330 {+-} 37 m/s for Permalloy, as estimated from numerical simulations. This critical velocity was found to be {nu}{sub c} = {eta}{sub c}{gamma} {radical}A{sub ex} with A{sub ex} the exchange stiffness, {gamma} the gyromagnetic ratio, and an estimated proportional constant {eta}{sub c} = 1.66 {+-} 0.18. This criterion does neither depend on driving force parameters nor on the dimension or geometry of the magnetic specimen. The phase diagrams for the vortex core switching criterion and its switching time with respect to both the strength and angular frequency of circular rotating magnetic fields were derived, which offer practical guidance for implementing vortex core switching into future solid state information storage devices.

  18. Investigation of pressure-tube and calandria-tube deformation following a single channel blockage event in ACR-700

    E-Print Network [OSTI]

    Gerardi, Craig Douglas

    2006-01-01T23:59:59.000Z

    The ACR-700 is an advanced pressure-tube (PT) reactor being developed by Atomic Energy of Canada Limited (AECL). As in conventional CANDU reactors, the PTs are horizontal. Each PT is surrounded by a calandria tube (CT), ...

  19. Investigation of Pressure-Tube and Calandria-Tube Deformation Following a Single Channel Blockage Event in ACR-700

    E-Print Network [OSTI]

    Gerardi, C.

    The ACR-700 is an advanced pressure-tube (PT) reactor being developed by Atomic Energy of Canada Limited (AECL). As in conventional CANDU reactors, the PTs are horizontal. Each PT is surrounded by a calandria tube (CT), ...

  20. Entanglement spectrum: Identification of the transition from vortex-liquid to vortex-lattice state in a weakly interacting rotating Bose-Einstein condensate

    SciTech Connect (OSTI)

    Liu Zhao; Guo Hongli; Fan Heng [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Vedral, Vlatko [Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543 (Singapore); Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore)

    2011-01-15T23:59:59.000Z

    We use entanglement to investigate the transition from vortex-liquid phase to vortex-lattice phase in a weakly interacting rotating Bose-Einstein condensate. For the torus geometry, the ground-state entanglement spectrum is analyzed to distinguish these two phases. The low-lying part of the ground-state entanglement spectrum, as well as the behavior of its lowest level, changes clearly when the transition occurs. For the sphere geometry, the entanglement gap in the conformal limit is also studied. We also show that the decrease in entanglement between particles can be regarded as a signal of the transition.

  1. Sheared bioconvection in a horizontal tube

    E-Print Network [OSTI]

    Croze, O A; Bees, M A; 10.1088/1478-3975/7/4/046001

    2010-01-01T23:59:59.000Z

    The recent interest in using microorganisms for biofuels is motivation enough to study bioconvection and cell dispersion in tubes subject to imposed flow. To optimize light and nutrient uptake, many microorganisms swim in directions biased by environmental cues (e.g. phototaxis in algae and chemotaxis in bacteria). Such taxes inevitably lead to accumulations of cells, which, as many microorganisms have a density different to the fluid, can induce hydrodynamic instabilites. The large-scale fluid flow and spectacular patterns that arise are termed bioconvection. However, the extent to which bioconvection is affected or suppressed by an imposed fluid flow, and how bioconvection influences the mean flow profile and cell transport are open questions. This experimental study is the first to address these issues by quantifying the patterns due to suspensions of the gravitactic and gyrotactic green biflagellate alga Chlamydomonas in horizontal tubes subject to an imposed flow. With no flow, the dependence of the domi...

  2. Laced permanent magnet quadrupole drift tube magnets

    SciTech Connect (OSTI)

    Feinberg, B.; Behrsing, G.U.; Halbach, K.; Marks, J.S.; Morrison, M.E.; Nelson, D.H.

    1989-03-01T23:59:59.000Z

    Twenty-three laced permanent magnet quadrupole drift tube magnets have been constructed, tested, and installed in the SuperHILAC heavy ion linear accelerator at LBL, marking the first accelerator use of this new type of quadrupole. The magnets consist of conventional tape-wound quadrupole electromagnets, using iron pole-pieces, with permanent magnet material (samarium cobalt) inserted between the poles to reduce the effects of saturation. The iron is preloaded with magnetic flux generated by the permanent magnet material, resulting in an asymmetrical saturation curve. Since the polarity of the individual quadrupole magnets in a drift tube linac is never reversed, we can take advantage of this asymmetrical saturation to provide about 20% greater focusing strength than is available with conventional quadrupoles, while replacing the vanadium permendur poletips with iron poletips. Comparisons between these magnets and conventional tape-wound quadrupoles will be presented. 3 refs., 5 figs.

  3. Fission of a multiphase membrane tube

    E-Print Network [OSTI]

    Jean-Marc Allain; Cornelis Storm; Aurelien Roux; Martine Ben Amar; Jean-Francois Joanny

    2004-09-01T23:59:59.000Z

    A common mechanism for intracellular transport is the use of controlled deformations of the membrane to create spherical or tubular buds. While the basic physical properties of homogeneous membranes are relatively well-known, the effects of inhomogeneities within membranes are very much an active field of study. Membrane domains enriched in certain lipids in particular are attracting much attention, and in this Letter we investigate the effect of such domains on the shape and fate of membrane tubes. Recent experiments have demonstrated that forced lipid phase separation can trigger tube fission, and we demonstrate how this can be understood purely from the difference in elastic constants between the domains. Moreover, the proposed model predicts timescales for fission that agree well with experimental findings.

  4. Ion sources for sealed neutron tubes

    SciTech Connect (OSTI)

    Burns, E.J.T. [Sandia National Labs., Albuquerque, NM (United States). Neutron Tube Dept.; Bischoff, G.C. [Lockheed Martin Specialty Components, Largo, FL (United States)

    1996-11-01T23:59:59.000Z

    Fast and thermal neutron activation analysis with sealed neutron generators has been used to detect oil (oil logging), hazardous waste, fissile material, explosives, and contraband (drugs). Sealed neutron generators, used in the above applications, must be small and portable, have good electrical efficiency and long life. The ion sources used in the sealed neutron tubes require high gas utilization efficiencies or low pressure operation with high ionization efficiencies. In this paper, the authors compare a number of gas ion sources that can be used in sealed neutron tubes. The characteristics of the most popular ion source, the axial Penning discharge will be discussed as part of the zetatron neutron generator. Other sources to be discussed include the SAMIS source and RF ion source.

  5. Coupled-cavity drift-tube linac

    DOE Patents [OSTI]

    Billen, J.H.

    1996-11-26T23:59:59.000Z

    A coupled-cavity drift-tube linac (CCDTL) combines features of the Alvarez drift-tube linac (DTL) and the {pi}-mode coupled-cavity linac (CCL). In one embodiment, each accelerating cavity is a two-cell, 0-mode DTL. The center-to-center distance between accelerating gaps is {beta}{lambda}, where {lambda} is the free-space wavelength of the resonant mode. Adjacent accelerating cavities have oppositely directed electric fields, alternating in phase by 180 degrees. The chain of cavities operates in a {pi}/2 structure mode so the coupling cavities are nominally unexcited. The CCDTL configuration provides an rf structure with high shunt impedance for intermediate velocity charged particles, i.e., particles with energies in the 20-200 MeV range. 5 figs.

  6. Source Terms for HFIR Beam Tube Shielding Analyses, and a Complete Shielding Analysis of the HB-3 Tube

    SciTech Connect (OSTI)

    Bucholz, J.A.

    2000-07-01T23:59:59.000Z

    The High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory is in the midst of a massive upgrade program to enhance experimental facilities. The reactor presently has four horizontal experimental beam tubes, all of which will be replaced or redesigned. The HB-2 beam tube will be enlarged to support more guide tubes, while the HB-4 beam tube will soon include a cold neutron source.

  7. The internal structure of a vortex in a two-dimensional superfluid with long healing length and its implications

    SciTech Connect (OSTI)

    Klein, Avraham [The Racah Institute of Physics, The Hebrew University of Jerusalem, 91904 (Israel); Aleiner, Igor L., E-mail: aleiner@phys.columbia.edu [Physics Department, Columbia University, New York, NY 10027 (United States); Agam, Oded [The Racah Institute of Physics, The Hebrew University of Jerusalem, 91904 (Israel); Physics Department, Columbia University, New York, NY 10027 (United States)

    2014-07-15T23:59:59.000Z

    We analyze the motion of quantum vortices in a two-dimensional spinless superfluid within Popov’s hydrodynamic description. In the long healing length limit (where a large number of particles are inside the vortex core) the superfluid dynamics is determined by saddle points of Popov’s action, which, in particular, allows for weak solutions of the Gross–Pitaevskii equation. We solve the resulting equations of motion for a vortex moving with respect to the superfluid and find the reconstruction of the vortex core to be a non-analytic function of the force applied on the vortex. This response produces an anomalously large dipole moment of the vortex and, as a result, the spectrum associated with the vortex motion exhibits narrow resonances lying within the phonon part of the spectrum, contrary to traditional view.

  8. Sheared bioconvection in a horizontal tube

    E-Print Network [OSTI]

    O. A. Croze; E. E. Ashraf; M. A. Bees

    2010-10-01T23:59:59.000Z

    The recent interest in using microorganisms for biofuels is motivation enough to study bioconvection and cell dispersion in tubes subject to imposed flow. To optimize light and nutrient uptake, many microorganisms swim in directions biased by environmental cues (e.g. phototaxis in algae and chemotaxis in bacteria). Such taxes inevitably lead to accumulations of cells, which, as many microorganisms have a density different to the fluid, can induce hydrodynamic instabilites. The large-scale fluid flow and spectacular patterns that arise are termed bioconvection. However, the extent to which bioconvection is affected or suppressed by an imposed fluid flow, and how bioconvection influences the mean flow profile and cell transport are open questions. This experimental study is the first to address these issues by quantifying the patterns due to suspensions of the gravitactic and gyrotactic green biflagellate alga Chlamydomonas in horizontal tubes subject to an imposed flow. With no flow, the dependence of the dominant pattern wavelength at pattern onset on cell concentration is established for three different tube diameters. For small imposed flows, the vertical plumes of cells are observed merely to bow in the direction of flow. For sufficiently high flow rates, the plumes progressively fragment into piecewise linear diagonal plumes, unexpectedly inclined at constant angles and translating at fixed speeds. The pattern wavelength generally grows with flow rate, with transitions at critical rates that depend on concentration. Even at high imposed flow rates, bioconvection is not wholly suppressed and perturbs the flow field.

  9. Sulphidation resistance of composite boiler tube materials

    SciTech Connect (OSTI)

    Kish, Joseph [McMaster University; Eng, Philip [FPInnovations; Singbeil, Douglas [FPInnovations; Keiser, James R [ORNL

    2008-01-01T23:59:59.000Z

    A lab-based testing program was undertaken to generate data to better define the sulphidation resistance of composite tubes installed in the lower-furnace section of black liquor recovery boilers. All composite tube cladding alloys tested were observed to have an acceptable corrosion rate at normal operating temperatures (up to 400 C) in the synthetic lower-furnace gaseous environment tested (1% H{sub 2}S-99% N{sub 2}). This acceptable corrosion resistance is due to the expected formation of a relatively protective chromium-rich inner sulphide scale. An increase in temperature up to 560 C was found to significantly increase the corrosion rate. Of the various alloys tested, Alloy HR11N exhibited the lowest corrosion rate at each of the three temperatures tested. Moreover, the corrosion rate was found not to be strongly dependent on the fabrication route (weld overlay versus co-extruded). To minimize corrosion, operating conditions that promote prolonged exposure to elevated temperatures in the lower-furnace section of black liquor recovery boilers should be avoided, regardless of the type of composite tube installed.

  10. THE DYNAMIC EVOLUTION OF TWISTED MAGNETIC FLUX TUBES IN A THREE-DIMENSIONAL CONVECTING FLOW. I. UNIFORMLY BUOYANT HORIZONTAL TUBES

    E-Print Network [OSTI]

    Abbett, Bill

    THE DYNAMIC EVOLUTION OF TWISTED MAGNETIC FLUX TUBES IN A THREE-DIMENSIONAL CONVECTING FLOW. I. UNIFORMLY BUOYANT HORIZONTAL TUBES Y. Fan High Altitude Observatory, National Center for Atmospheric-dimensional numerical simulations of the dynamic evolution of uniformly buoyant, twisted horizontal magnetic flux tubes

  11. Tube cutter tool and method of use for coupon removal

    DOE Patents [OSTI]

    Nachbar, Henry D. (Ballston Lake, NY); Etten, Jr., Marvin P. (Ballston Lake, NY); Kurowski, Paul A. (Scotia, NY)

    1997-01-01T23:59:59.000Z

    A tube cutter tool is insertable into a tube for cutting a coupon from a damaged site on the exterior of the tube. Prior to using the tool, the damaged site is first located from the interior of the tube using a multi-coil pancake eddy current test probe. The damaged site is then marked. A fiber optic probe is used to monitor the subsequent cutting procedure which is performed using a hole saw mounted on the tube cutter tool. Prior to completion of the cutting procedure, a drill in the center of the hole saw is drilled into the coupon to hold it in place.

  12. Tube cutter tool and method of use for coupon removal

    DOE Patents [OSTI]

    Nachbar, H.D.; Etten, M.P. Jr.; Kurowski, P.A.

    1997-05-06T23:59:59.000Z

    A tube cutter tool is insertable into a tube for cutting a coupon from a damaged site on the exterior of the tube. Prior to using the tool, the damaged site is first located from the interior of the tube using a multi-coil pancake eddy current test probe. The damaged site is then marked. A fiber optic probe is used to monitor the subsequent cutting procedure which is performed using a hole saw mounted on the tube cutter tool. Prior to completion of the cutting procedure, a drill in the center of the hole saw is drilled into the coupon to hold it in place. 4 figs.

  13. Recirculating wedges for metal-vapor plasma tubes

    DOE Patents [OSTI]

    Hall, J.P.; Sawvel, R.M.; Draggoo, V.G.

    1994-06-28T23:59:59.000Z

    A metal vapor laser is disclosed that recycles condensed metal located at the terminal ends of a plasma tube back toward the center of the tube. A pair of arcuate wedges are incorporated on the bottom of the plasma tube near the terminal ends. The wedges slope downward toward the center so that condensed metal may be transported under the force of gravity away from the terminal ends. The wedges are curved to fit the plasma tube to thereby avoid forming any gaps within the tube interior. 8 figures.

  14. Recirculating wedges for metal-vapor plasma tubes

    DOE Patents [OSTI]

    Hall, Jerome P. (Livermore, CA); Sawvel, Robert M. (Modesto, CA); Draggoo, Vaughn G. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    A metal vapor laser is disclosed that recycles condensed metal located at the terminal ends of a plasma tube back toward the center of the tube. A pair of arcuate wedges are incorporated on the bottom of the plasma tube near the terminal ends. The wedges slope downward toward the center so that condensed metal may be transported under the force of gravity away from the terminal ends. The wedges are curved to fit the plasma tube to thereby avoid forming any gaps within the tube interior.

  15. Dynamics of a relativistic Rankine vortex for a two-constituent superfluid in a weak perturbation of cylindrical symmetry

    E-Print Network [OSTI]

    B. Boisseau

    1999-01-18T23:59:59.000Z

    From a recent study of a stationary cylindrical solution for a relativistic two-constituent superfluid at low temperature limit, we propose to specify this solution under the form of a relativistic generalisation of a Rankine vortex (Potential vortex whose the core has a solid body rotation).Then we establish the dynamics of the central line of this vortex by supposing that the deviation from the cylindrical configuration is weak in the neighbourhood of the core of the vortex. In "stiff" material the Nambu-Goto equations are obtained.

  16. Segmented lasing tube for high temperature laser assembly

    DOE Patents [OSTI]

    Sawicki, Richard H. (Danville, CA); Alger, Terry W. (Tracy, CA); Finucane, Raymond G. (Pleasanton, CA); Hall, Jerome P. (Livermore, CA)

    1996-01-01T23:59:59.000Z

    A high temperature laser assembly capable of withstanding operating temperatures in excess of 1500.degree. C. is described comprising a segmented cylindrical ceramic lasing tube having a plurality of cylindrical ceramic lasing tube segments of the same inner and outer diameters non-rigidly joined together in axial alignment; insulation of uniform thickness surround the walls of the ceramic lasing tube; a ceramic casing, preferably of quartz, surrounding the insulation; and a fluid cooled metal jacket surrounds the ceramic casing. In a preferred embodiment, the inner surface of each of the ceramic lasing tube segments are provided with a pair of oppositely spaced grooves in the wall thereof parallel to the center axis of the segmented cylindrical ceramic lasing tube, and both of the grooves and the center axis of the segmented cylindrical ceramic lasing tube lie in a common plane, with the grooves in each ceramic lasing tube segment in circumferential alignment with the grooves in the adjoining ceramic lasing tube segments; and one or more ceramic plates, all lying in a common plane to one another and with the central axis of the segmented ceramic lasing tube, are received in the grooves to provide additional wall area in the segmented ceramic lasing tube for collision and return to ground state of metastable metal atoms within the segmented ceramic lasing tube.

  17. Synthesis and characterization of Fe(III)-silicate precipitation tubes

    SciTech Connect (OSTI)

    Parmar, K.; Pramanik, A.K. [National Metallurgical Laboratory, Council of Scientific and Industrial Research, Burmamines, Jamshedpur 831007 (India)] [National Metallurgical Laboratory, Council of Scientific and Industrial Research, Burmamines, Jamshedpur 831007 (India); Bandyopadhya, N.R. [Bengal Engineering and Science University, Shibpur, Howrah 711103 (India)] [Bengal Engineering and Science University, Shibpur, Howrah 711103 (India); Bhattacharjee, S., E-mail: santanu@nmlindia.org [National Metallurgical Laboratory, Council of Scientific and Industrial Research, Burmamines, Jamshedpur 831007 (India)

    2010-09-15T23:59:59.000Z

    Fe(III)-silicate precipitation tubes synthesized through 'silica garden' route have been characterized using a number of analytical techniques including X-ray diffraction, infrared spectroscopy, atomic force microscopy, scanning and transmission electron microscopy. These tubes are brittle and amorphous and are hierarchically built from smaller tubes of 5-10 nm diameters. They remain amorphous at least up to 650 {sup o}C. Crystobalite and hematite are the major phases present in Fe(III)-silicate tubes heated at 850 {sup o}C. Morphology and chemical compositions at the external and internal walls of these tubes are remarkably different. These tubes are porous with high BET surface area of 291.2 m{sup 2}/g. Fe(III)-silicate tubes contain significant amount of physically and chemically bound moisture. They show promise as an adsorbent for Pb(II), Zn(II), and Cr(III) in aqueous medium.

  18. Project Controls

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1997-03-28T23:59:59.000Z

    Project controls are systems used to plan, schedule, budget, and measure the performance of a project/program. The cost estimation package is one of the documents that is used to establish the baseline for project controls. This chapter gives a brief description of project controls and the role the cost estimation package plays.

  19. The London theory of the crossing-vortex lattice in highly anisotropic layered superconductors

    E-Print Network [OSTI]

    S. E. Savel'ev; J. Mirkovic; K. Kadowaki

    2001-05-18T23:59:59.000Z

    A novel description of Josephson vortices (JVs) crossed by the pancake vortices (PVs) is proposed on the basis of the anisotropic London theory. The field distribution of a JV and its energy have been calculated for both dense ($a\\lambda_J$) PV lattices with distance $a$ between PVs, and the nonlinear JV core size $\\lambda_J$. It is shown that the ``shifted'' PV lattice (PVs displaced mainly along JVs in the crossing vortex lattice structure), formed in high out-of-plane magnetic fields transforms into the PV lattice ``trapped'' by the JV sublattice at a certain field, lower than $\\Phi_0/\\gamma^2s^2$, where $\\Phi_0$ is the flux quantum, $\\gamma$ is the anisotropy parameter and $s$ is the distance between CuO$_2$ planes. With further decreasing $B_z$, the free energy of the crossing vortex lattice structure (PV and JV sublattices coexist separately) can exceed the free energy of the tilted lattice (common PV-JV vortex structure) in the case of $\\gamma s<\\lambda_{ab}$ with the in-plane penetration depth $\\lambda_{ab}$ if the low ($B_x<\\gamma\\Phi_0/\\lambda_{ab}^2$) or high ($B_x\\gtrsim \\Phi_0/\\gamma s^2$) in-plane magnetic field is applied. It means that the crossing vortex structure is realized in the intermediate field orientations, while the tilted vortex lattice can exist if the magnetic field is aligned near the $c$-axis and the $ab$-plane as well. In the intermediate in-plane fields $\\gamma\\Phi_0/\\lambda_{ab}^2\\lesssim B_x \\lesssim \\Phi_0/\\gamma s^2$, the crossing vortex structure with the ``trapped'' PV sublattice seems to settle in until the lock-in transition occurs since this structure has the lower energy with respect to the tilted vortex structure in the magnetic field ${\\vec H}$ oriented near the $ab$-plane.

  20. Past START Projects | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking ofOilNEWResponse(Expired) |CERCLA ProcessDepartmentPast START Projects Past

  1. Power Metering Project | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreakingMay 2015 < prev next > Sun Mon Tue Wed May 28-29,Metering Project Power

  2. Instream Flow Project | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking of BlytheDepartment ofEnergy1Energy MaintainingInstream Flow Project

  3. Funding Federal Energy and Water Projects

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdf Flash2006-52.pdf0.pdfDepartment ofEnergy 3 FuelModel |MinimalProjectsFEDERAL

  4. Improving Project Management | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking of BlytheDepartment of Energy IRSJuly 2012|| DepartmentImproving Project

  5. Project Fact Sheet Project Update

    E-Print Network [OSTI]

    Project Fact Sheet Project Update: Project Brief: The works cover the refurbishment of floors 4, 5, with `wet' labs for molecular biology, materials characterisation, cell culture and flow studies, and `dry operating theatre. The Bionanotechnology Centre is one of the projects funded from the UK Government's £20

  6. Project Fact Sheet Project Brief

    E-Print Network [OSTI]

    .union.ic.ac.uk/marketing/building Construction Project Team: Project Facts & Figures: Budget: £1,400,000 Funding Source: Capital PlanProject Fact Sheet Project Brief: In the first phase of the Union Building re that it adapts to meet the needs of a changing student body. The re-development plans are grounded in a full

  7. Project Fact Sheet Project Brief

    E-Print Network [OSTI]

    Facts & Figures: Budget: £3,500,000 Funding Source: SRIF III Construction Project Programme: StartProject Fact Sheet Project Brief: This project refurbished half of the 5th and 7th floors of work includes: · Building fabric replacement and revised space planning · New mechanical and electrical

  8. Vortex generation in protoplanetary disks with an embedded giant planet

    E-Print Network [OSTI]

    M. de Val-Borro; P. Artymowicz; G. D'Angelo; A. Peplinski

    2007-06-21T23:59:59.000Z

    Vortices in protoplanetary disks can capture solid particles and form planetary cores within shorter timescales than those involved in the standard core-accretion model. We investigate vortex generation in thin unmagnetized protoplanetary disks with an embedded giant planet with planet to star mass ratio $10^{-4}$ and $10^{-3}$. Two-dimensional hydrodynamical simulations of a protoplanetary disk with a planet are performed using two different numerical methods. The results of the non-linear simulations are compared with a time-resolved modal analysis of the azimuthally averaged surface density profiles using linear perturbation theory. Finite-difference methods implemented in polar coordinates generate vortices moving along the gap created by Neptune-mass to Jupiter-mass planets. The modal analysis shows that unstable modes are generated with growth rate of order $0.3 \\Omega_K$ for azimuthal numbers m=4,5,6, where $\\Omega_K$ is the local Keplerian frequency. Shock-capturing Cartesian-grid codes do not generate very much vorticity around a giant planet in a standard protoplanetary disk. Modal calculations confirm that the obtained radial profiles of density are less susceptible to the growth of linear modes on timescales of several hundreds of orbital periods. Navier-Stokes viscosity of the order $\

  9. Topological superconductivity, topological confinement, and the vortex quantum Hall effect

    SciTech Connect (OSTI)

    Diamantini, M. Cristina; Trugenberger, Carlo A. [INFN and Dipartimento di Fisica, University of Perugia, via A. Pascoli, I-06100 Perugia (Italy); SwissScientific, chemin Diodati 10, CH-1223 Cologny (Switzerland)

    2011-09-01T23:59:59.000Z

    Topological matter is characterized by the presence of a topological BF term in its long-distance effective action. Topological defects due to the compactness of the U(1) gauge fields induce quantum phase transitions between topological insulators, topological superconductors, and topological confinement. In conventional superconductivity, because of spontaneous symmetry breaking, the photon acquires a mass due to the Anderson-Higgs mechanism. In this paper we derive the corresponding effective actions for the electromagnetic field in topological superconductors and topological confinement phases. In topological superconductors magnetic flux is confined and the photon acquires a topological mass through the BF mechanism: no symmetry breaking is involved, the ground state has topological order, and the transition is induced by quantum fluctuations. In topological confinement, instead, electric charge is linearly confined and the photon becomes a massive antisymmetric tensor via the Stueckelberg mechanism. Oblique confinement phases arise when the string condensate carries both magnetic and electric flux (dyonic strings). Such phases are characterized by a vortex quantum Hall effect potentially relevant for the dissipationless transport of information stored on vortices.

  10. EM International Project Submission Template | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the YouTube|6721 Federal Register / Vol.6: Record ofRecordCollaboratesDepartment ofProject

  11. CERCLA Sites Quality Assurance Project Plan | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the YouTube platformBuilding Removal OngoingCERCLA Sites Quality Assurance Project Plan

  12. (SSS)Project Dashboard 2015-05-28.xls

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the YouTube platform is always evolving, so are our1pm EST |Department'Project

  13. 2014 Solid-State Lighting Project Portfolio | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the YouTube platform is always evolving, soFuel Cell24 Solid-State Lighting Project

  14. The Benjamin Shock Tube Problem in KULL

    SciTech Connect (OSTI)

    Ulitsky, M

    2005-08-26T23:59:59.000Z

    The goal of the EZturb mix model in KULL is to predict the turbulent mixing process as it evolves from Rayleigh-Taylor, Richtmyer-Meshkov, or Kelvin-Helmholtz instabilities. In this report we focus on a simple example of the Richtmyer-Meshkov instability (which occurs when a shock hits an interface between fluids of different densities) without the complication of reshock. The experiment by Benjamin et al. involving a Mach 1.21 incident shock striking an air / SF6 interface, is a good one to model and understand before moving onto shock tubes that follow the growth of the turbulent mixing zone from first shock through well after reshock.

  15. Effects of grids in drift tubes

    SciTech Connect (OSTI)

    Okamura M.; Yamauchi, H.

    2012-05-20T23:59:59.000Z

    In 2011, we upgraded a 201 MHz buncher in the proton injector for the alternating gradient synchrotron (AGS) - relativistic heavy ion collider (RHIC) complex. In the buncher we installed four grids made of tungsten to improve the transit time factor. The grid installed drift tubes have 32 mm of inner diameter and the each grid consists of four quadrants. The quadrants were cut out precisely from 1mm thick tungsten plates by a computerized numerically controlled (CNC) wire cutting electrical discharge machining (EDM). The 3D electric field of the grid was simulated.

  16. Sound Coiled-Tubing Drilling Practices

    SciTech Connect (OSTI)

    Williams, Thomas; Deskins, Greg (Maurer Technology Inc.); Ward, Stephen L. (Advantage Energy Services Ltd); Hightower, Mel

    2001-09-30T23:59:59.000Z

    This Coiled-Tubing Drilling (CTD) Sound Practices Manual provides tools needed by CTD engineers and supervisors to plan, design and perform safe, successful CTD operations. As emphasized throughout, both careful planning and attention to detail are mandatory for success. A bibliography of many useful CTD references is presented in Chapter 6. This manual is organized according to three processes: 1) Pre-Job Planning Process, 2) Operations Execution Process, and 3) Post-Job Review Process. Each is discussed in a logical and sequential format.

  17. The Monitored Drift Tube Chambers of Atlas

    SciTech Connect (OSTI)

    Ventura, S. [INFN - Laboratori Nazionali di Frascati (Italy)

    2005-10-12T23:59:59.000Z

    The Atlas experiment has been designed to explore the high energy physics frontier at the TeV energy scale and to investigate on the physics of the Standard Model and beyond at the Large Hadron Collider (LHC) at Cern. The Muon Spectrometer represents the most part of the Atlas detector. It has been designed to provide standalone measurement of the transverse muon momenta with a relative accuracy of 3% over a wide momentum range up to 10% for momenta of 1 TeV. This high accuracy is provided by the Monitored Drift-Tube chambers (MDT) which can determine the track trajectory with a precision of 40 {mu}m.

  18. YouTube | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directed off Energy.gov. Are you sure you wantJoin us for|IdahotheWhat is the FOIA ? WhatWork PlansYouTube

  19. Widget:YouTube | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTri GlobalJumpGoogleAreaMapUtilityRateEntryHelperVideoVimeo JumpYouTube

  20. Fuel cell tubes and method of making same

    DOE Patents [OSTI]

    Borglum, Brian P. (Edgewood, PA)

    1999-11-30T23:59:59.000Z

    A method of manufacturing porous ceramic tubes for fuel cells with improved properties and higher manufacturing yield is disclosed. The method involves extruding a closed end fuel cell tube, such as an air electrode of a solid oxide fuel cell, in which the closed end also functions as the sintering support. The resultant fuel cell tube has a superior porosity distribution which allows improved diffusion of oxygen at the closed end of the tube during operation of the fuel cell. Because this region has the highest current density, performance enhancement and improved reliability of the fuel cell tube result. Furthermore, the higher manufacturing yield associated with the present method decreases the overall fuel cell cost. A method of manufacturing porous ceramic tubes for fuel cells with improved properties and higher manufacturing yield is disclosed. The method involves extruding a closed end fuel cell tube, such as an air electrode of a solid oxide fuel cell, in which the closed end also functions as the sintering support. The resultant fuel cell tube has a superior porosity distribution which allows improved diffusion of oxygen at the closed end of the tube during operation of the fuel cell. Because this region has the highest current density, performance enhancement and improved reliability of the fuel cell tube result. Furthermore, the higher manufacturing yield associated with the present method decreases the overall fuel cell cost.

  1. OTEC cold water pipe design for problems caused by vortex-excited oscillations

    SciTech Connect (OSTI)

    Griffin, O. M.

    1980-03-14T23:59:59.000Z

    Vortex-excited oscillations of marine structures result in reduced fatigue life, large hydrodynamic forces and induced stresses, and sometimes lead to structural damage and to diestructive failures. The cold water pipe of an OTEC plant is nominally a bluff, flexible cylinder with a large aspect ratio (L/D = length/diameter), and is likely to be susceptible to resonant vortex-excited oscillations. The objective of this report is to survey recent results pertaining to the vortex-excited oscillations of structures in general and to consider the application of these findings to the design of the OTEC cold water pipe. Practical design calculations are given as examples throughout the various sections of the report. This report is limited in scope to the problems of vortex shedding from bluff, flexible structures in steady currents and the resulting vortex-excited oscillations. The effects of flow non-uniformities, surface roughness of the cylinder, and inclination to the incident flow are considered in addition to the case of a smooth cyliner in a uniform stream. Emphasis is placed upon design procedures, hydrodynamic coefficients applicable in practice, and the specification of structural response parameters relevant to the OTEC cold water pipe. There are important problems associated with in shedding of vortices from cylinders in waves and from the combined action of waves and currents, but these complex fluid/structure interactions are not considered in this report.

  2. A Robust Numerical Method for Integration of Point-Vortex Trajectories in Two Dimensions

    E-Print Network [OSTI]

    Spencer A. Smith; Bruce M. Boghosian

    2010-11-19T23:59:59.000Z

    The venerable 2D point-vortex model plays an important role as a simplified version of many disparate physical systems, including superfluids, Bose-Einstein condensates, certain plasma configurations, and inviscid turbulence. This system is also a veritable mathematical playground, touching upon many different disciplines from topology to dynamic systems theory. Point-vortex dynamics are described by a relatively simple system of nonlinear ODEs which can easily be integrated numerically using an appropriate adaptive time stepping method. As the separation between a pair of vortices relative to all other inter-vortex length scales decreases, however, the computational time required diverges. Accuracy is usually the most discouraging casualty when trying to account for such vortex motion, though the varying energy of this ostensibly Hamiltonian system is a potentially more serious problem. We solve these problems by a series of coordinate transformations: We first transform to action-angle coordinates, which, to lowest order, treat the close pair as a single vortex amongst all others with an internal degree of freedom. We next, and most importantly, apply Lie transform perturbation theory to remove the higher-order correction terms in succession. The overall transformation drastically increases the numerical efficiency and ensures that the total energy remains constant to high accuracy.

  3. Numerical study of Kelvin-Helmholtz instability by the point vortex method

    SciTech Connect (OSTI)

    Krasny, R.

    1983-01-01T23:59:59.000Z

    Rosenhead's classical point vortex numerical method for studying the evolution of a vortex sheet from analytic initial data (Kelvin-Helmholtz instability) is examined using the discrete Fourier analysis techniques of Sulem, Sulem and Frisch. One cause for the chaotic motion previously observed in computations using a large number of vortices is that short wavelength perturbations are introduced spuriously by finite precision arithmetic and become amplified by the model's dynamics. Methods for controlling this source of error are given, and the results confirm the formation of a singularity in a finite time which was previously found by Moore and Meiron, Baker and Orszag using different techniques of analysis. A cusp forms in the vortex sheet strength at the critical time, explaining the onset of erratic particle motion in applications of the numerical methods of Van de Vooren and Fink and Soh to this problem. Unlike those methods, the point vortex approximation remains consistent at the critical time and results of a long time calculation are presented. The singularity is interpreted physically as a discontinuity in the strain rate along the vortex sheet and also as the start of roll up on a small scale. The author numerically studies some aspects of the dependence of the solution on the initial condition and finds agreement with Moore's asymptotic relation between the initial amplitude and the critial time.

  4. Wake Tracking and the Detection of Vortex Rings by the Canal Lateral Line of Fish Jan-Moritz P. Franosch,1

    E-Print Network [OSTI]

    van Hemmen, J. Leo

    that pass a fish later- ally [19] as well as vortex rings that are part of a von Ka´rma´n vortex street [20 by the lateral-line sensors so as to enable fish to follow a vortex street. DOI: 10.1103/PhysRevLett.103Wake Tracking and the Detection of Vortex Rings by the Canal Lateral Line of Fish Jan-Moritz P

  5. Final Technical Report - High-Performance, Oxide-Dispersion-Strengthened Tubes for Production of Ethylene adn Other Industrial Chemicals

    SciTech Connect (OSTI)

    McKimpson, Marvin G.

    2006-04-06T23:59:59.000Z

    This project was undertaken by Michigan Technological University and Special Metals Corporation to develop creep-resistant, coking-resistant oxide-dispersion-strengthened (ODS) tubes for use in industrial-scale ethylene pyrolysis and steam methane reforming operations. Ethylene pyrolysis tubes are exposed to some of the most severe service conditions for metallic materials found anywhere in the chemical process industries, including elevated temperatures, oxidizing atmospheres and high carbon potentials. During service, hard deposits of carbon (coke) build up on the inner wall of the tube, reducing heat transfer and restricting the flow of the hydrocarbon feedstocks. About every 20 to 60 days, the reactor must be taken off-line and decoked by burning out the accumulated carbon. This decoking costs on the order of $9 million per year per ethylene plant, accelerates tube degradation, and requires that tubes be replaced about every 5 years. The technology developed under this program seeks to reduce the energy and economic cost of coking by creating novel bimetallic tubes offering a combination of improved coking resistance, creep resistance and fabricability not available in current single-alloy tubes. The inner core of this tube consists of Incoloy(R) MA956, a commercial ferritic Fe-Cr-Al alloy offering a 50% reduction in coke buildup combined with improved carburization resistance. The outer sheath consists of a new material - oxide dispersion strengthened (ODS) Alloy 803(R) developed under the program. This new alloy retains the good fireside environmental resistance of Alloy 803, a commercial wrought alloy currently used for ethylene production, and provides an austenitic casing to alleviate the inherently-limited fabricability of the ferritic Incoloy(R) MA956 core. To provide mechanical compatibility between the two alloys and maximize creep resistance of the bimetallic tube, both the inner Incoloy(R) MA956 and the outer ODS Alloy 803 are oxide dispersion strengthened materials produced using mechanical alloying technology. To minimize cost, the bimetallic tube is produced by direct powder co-extrusion. This technology has potential for domestic energy savings of up to 4.1 trillion BTU/year (4.3 x 1015J/year) and a reduction of 370,000 tons (340,000 tonnes) of CO2 emissions in short-residence-time ethylene furnaces. This represents an energy savings and CO2 emissions reduction of about 3.3%. If the technology is also applied to other types of ethylene pyrolysis furnaces, total energy savings and CO2 emissions reductions could increase by up to five times. The work involved: Developing powder and consolidation processing protocols to produce an oxide-dispersion strengthened variant of Alloy 803 exhibiting creep strength comparable to Incoloy? Alloy MA956, Developing a direct powder co-extrusion protocol for fabricating co-extruded bimetallic Incoloy? Alloy MA956 / ODS Alloy 803 tubes, Characterizing the properties of the ODS Alloy 803 material, the welding characteristics of the bimetallic tubes, and the coking characteristics of the Incoloy? MA956 alloy, and Documenting the potential energy savings and user requirements for these bimetallic pyrolysis furnace tubes. The project demonstrated that oxide dispersion strengthened Alloy 803 can be produced successfully using conventional mechanical alloying technology. The oxide dispersion strengthened bimetallic radiant coil technology explored under this program has significant potential for energy savings and productivity improvements for domestic ethylene producers. In today's competitive market, however, domestic furnace manufacturers and ethylene producers appear reluctant to pay any cost premium for higher-performance coil materials offering either higher temperature capabilities or longer service life. Interest in oxide dispersion strengthened radiant coils is likely to increase if furnace and ethylene producers begin to focus more on increasing tube wall temperatures to improve productivity.

  6. Laced permanent magnet quadrupole drift tube magnets

    SciTech Connect (OSTI)

    Feinberg, B.; Behrsing, G.U.; Halbach, K.; Marks, J.S.; Morrison, M.E.; Nelson, D.H.

    1988-10-01T23:59:59.000Z

    A laced permanent magnet quadrupole drift tube magnet has been constructed for a proof-of-principle test. The magnet is a conventional tape-wound quadrupole electromagnet, using iron pole- pieces, with the addition of permanent magnet material (neodymium iron) between the poles to reduce the effects of saturation. The iron is preloaded with magnetic flux generated by the permanent magnet material, resulting in an asymmetrical saturation curve. Since the polarity of the quadrupole magnets in a drift tube linac is not reversed we can take advantage of this asymmetrical saturation to provide greater focusing strength. The magnet configuration has been optimized and the vanadium permendur poles needed in a conventional quadrupole have been replaced with iron poles. The use of permanent magnet material has allowed us to increase the focusing strength of the magnet by about 20% over that of a conventional tape-wound quadrupole. Comparisons will be made between this magnet and the conventional tape-wound quadrupole. 3 refs., 5 figs.

  7. Femtosecond laser fabrication of micro and nano-disks in single layer graphene using vortex Bessel beams

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Femtosecond laser fabrication of micro and nano-disks in single layer graphene using vortex Bessel deposition graphene on glass substrate using femtosecond laser ablation with vortex Bessel beams. The fabricated graphene disks with diameters ranging from 650 nm to 4 µm were characterized by spatially resolved

  8. Joule heating induced by vortex motion in a type-II superconductor Z. L. Xiao and E. Y. Andrei

    E-Print Network [OSTI]

    Andrei, Eva Y.

    Joule heating induced by vortex motion in a type-II superconductor Z. L. Xiao and E. Y. Andrei-II superconductor due to Joule heating induced by vortex motion. The effect of Joule heating is detected s duration, where the Joule heating is negligible and saturates, respectively. The thermometry is based

  9. Bow-wave-like hydraulic jump and horseshoe vortex around an obstacle in a supercritical open channel flow

    E-Print Network [OSTI]

    Boyer, Edmond

    Bow-wave-like hydraulic jump and horseshoe vortex around an obstacle in a supercritical open the obstacle, two main flow structures are observed: i a hydraulic jump in the near-surface region and ii turbulent regime , the detachment length of the hydraulic jump exceeds the one of the horseshoe vortex

  10. Vortex dipoles by PIV method Click here to see the images and the short movies from this lab

    E-Print Network [OSTI]

    deYoung, Brad

    Introduction A vortex dipole is a jet flow with a system of two vortices of opposite sign at its front. Vortex of density stratification. The simplest case of stratification is a two-layer system. A Plexiglas tank a two-layer system without mixing the fluids, one can float a sheet of paper on top of the salt water

  11. Quantitative determination of vortex core dimensions in head-to-head domain walls using off-axis electron holography

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    transformations.7 Recent experimental reports confirm these predictions of domain wall movement8Quantitative determination of vortex core dimensions in head-to-head domain walls using off-dimensional characterization of vortex core spin structures, which is important for future magnetic data storage based

  12. Role of the Vortex-Core Energy on the Berezinskii-Kosterlitz-Thouless Transition in Thin Films of NbN

    E-Print Network [OSTI]

    Raychaudhuri, Pratap

    Role of the Vortex-Core Energy on the Berezinskii-Kosterlitz-Thouless Transition in Thin Films-Kosterlitz-Thouless (BKT) transition in thin films of NbN at various film thickness, by probing the effect of vortex played by the vortex-core energy in determining the characteristic signatures of the BKT physics, and we

  13. A model of the lateral line of fish for vortex sensing This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Mohseni, Kamran

    field around a fish's body in the presence of a Karman vortex street. Karman and reverse Karman streets LLTC model could explain how a fish identifies the characteristics of a Karman vortex street shed that the main characteristics of a vortex street including the magnitude of vortices, their translational speed

  14. Heat transfer in bundles of finned tubes in crossflow

    SciTech Connect (OSTI)

    Stasiulevicius, J.; Skrinska, A.; Zukauskas, A.; Hewitt, G.F.

    1986-01-01T23:59:59.000Z

    This book provides correlations of heat transfer and hydraulic data for bundles of finned tubes in crossflow at high Reynolds numbers. Results of studies of the effectiveness of the fin, local, and mean heat transfer coefficients are presented. The effect of geometric parameters of the fins and of the location of tubes in the bundle on heat transfer and hydraulic drag are described. The resistance of the finned tube bundles under study and other factors are examined.

  15. LANSCE Drift Tube Linac Water Control System Refurbishment

    SciTech Connect (OSTI)

    Marroquin, Pilar S. [Los Alamos National Laboratory

    2011-01-01T23:59:59.000Z

    There are several refurbishment projects underway at the Los Alamos National Laboratory LANSCE linear accelerator. Systems involved are: RF, water cooling, networks, diagnostics, timing, controls, etc. The Drift Tube Linac (DTL) portion of the accelerator consists of four DTL tanks, each with three independent water control systems. The systems are about 40 years old, use outdated and non-replaceable equipment and NIM bin control modules, are beyond their design life and provide unstable temperature control. Insufficient instrumentation and documentation further complicate efforts at maintaining system performance. Detailed design of the replacement cooling systems is currently in progress. Previous design experience on the SNS accelerator water cooling systems will be leveraged, see the SNS DTL FDR. Plans call for replacement of water piping, manifolds, pumps, valves, mix tanks, instrumentation (flow, pressure and temperature) and control system hardware and software. This presentation will focus on the control system design with specific attention on planned use of the National Instruments Compact RIO platform with the Experimental Physics and Industrial Control system (EPICS) software toolkit.

  16. Photomultiplier tube failure under hydrostatic pressure in future neutrino detectors

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chambliss, K.; Diwan, M.; Simos, N.; Sundaram, S. K.

    2014-10-01T23:59:59.000Z

    Failure of photomultiplier tubes (PMTs) under hydrostatic pressure is a concern in neutrino detection, specifically, in the proposed Long-Baseline Neutrino Experiment project. Controlled hydrostatic implosion tests were performed on prototypic PMT bulbs of 10-inch diameter and recorded using high speed filming techniques to capture failures in detail. These high-speed videos were analyzed frame-by-frame in order to identify the origin of a crack, measure the progression of individual crack along the surface of the bulb as it propagates through the glass, and estimate crack velocity. Crack velocity was calculated for each individual crack, and an average velocity was determined for allmore »measurable cracks on each bulb. Overall, 32 cracks were measured in 9 different bulbs tested. Finite element modeling (FEM) of crack formation and growth in prototypic PMT shows stress concentration near the middle section of the PMT bulbs that correlates well with our crack velocity measurements in that section. The FEM model predicts a crack velocity value that is close to the terminal crack velocity reported. Our measurements also reveal significantly reduced crack velocities compared to terminal crack velocities measured in glasses using fracture mechanics testing and reported in literature.« less

  17. Photomultiplier tube failure under hydrostatic pressure in future neutrino detectors

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chambliss, K. [Alfred Univ., Alfred, NY (United States). Multifunctional Materials Lab, Kazuo Inamori School of Engineering; Diwan, M. [Alfred Univ., Alfred, NY (United States). Multifunctional Materials Lab, Kazuo Inamori School of Engineering; Simos, N. [Brookhaven National Laboratory (BNL), Upton, NY (United States); Sundaram, S. K. [Alfred Univ., Alfred, NY (United States). Brookhaven National Laboratory (BNL), Upton, NY (United States)

    2014-10-01T23:59:59.000Z

    Failure of photomultiplier tubes (PMTs) under hydrostatic pressure is a concern in neutrino detection, specifically, in the proposed Long-Baseline Neutrino Experiment project. Controlled hydrostatic implosion tests were performed on prototypic PMT bulbs of 10-inch diameter and recorded using high speed filming techniques to capture failures in detail. These high-speed videos were analyzed frame-by-frame in order to identify the origin of a crack, measure the progression of individual crack along the surface of the bulb as it propagates through the glass, and estimate crack velocity. Crack velocity was calculated for each individual crack, and an average velocity was determined for all measurable cracks on each bulb. Overall, 32 cracks were measured in 9 different bulbs tested. Finite element modeling (FEM) of crack formation and growth in prototypic PMT shows stress concentration near the middle section of the PMT bulbs that correlates well with our crack velocity measurements in that section. The FEM model predicts a crack velocity value that is close to the terminal crack velocity reported. Our measurements also reveal significantly reduced crack velocities compared to terminal crack velocities measured in glasses using fracture mechanics testing and reported in literature.

  18. Vortex combustor for low NOX emissions when burning lean premixed high hydrogen content fuel

    DOE Patents [OSTI]

    Steele, Robert C; Edmonds, Ryan G; Williams, Joseph T; Baldwin, Stephen P

    2012-11-20T23:59:59.000Z

    A trapped vortex combustor. The trapped vortex combustor is configured for receiving a lean premixed gaseous fuel and oxidant stream, where the fuel includes hydrogen gas. The trapped vortex combustor is configured to receive the lean premixed fuel and oxidant stream at a velocity which significantly exceeds combustion flame speed in a selected lean premixed fuel and oxidant mixture. The combustor is configured to operate at relatively high bulk fluid velocities while maintaining stable combustion, and low NOx emissions. The combustor is useful in gas turbines in a process of burning synfuels, as it offers the opportunity to avoid use of diluent gas to reduce combustion temperatures. The combustor also offers the possibility of avoiding the use of selected catalytic reaction units for removal of oxides of nitrogen from combustion gases exiting a gas turbine.

  19. Random Vortex-Street Model for a Self-Similar Plane Turbulent Jet

    E-Print Network [OSTI]

    Victor L'vov; Anna Pomyalov; Itamar Procaccia; Rama Govindarajan

    2008-03-18T23:59:59.000Z

    We ask what determines the (small) angle of turbulent jets. To answer this question we first construct a deterministic vortex-street model representing the large scale structure in a self-similar plane turbulent jet. Without adjustable parameters the model reproduces the mean velocity profiles and the transverse positions of the large scale structures, including their mean sweeping velocities, in a quantitative agreement with experiments. Nevertheless the exact self similar arrangement of the vortices (or any other deterministic model) necessarily leads to a collapse of the jet angle. The observed (small) angle results from a competition between vortex sweeping tending to strongly collapse the jet and randomness in the vortex structure, with the latter resulting in a weak spreading of the jet.

  20. Shear Banding and Spatiotemporal Oscillations in Vortex Matter in Nanostructured Superconductors

    E-Print Network [OSTI]

    C. Reichhardt; C. J. Olson Reichhardt

    2009-12-16T23:59:59.000Z

    We propose a simple nanostructured pinning array geometry where a rich variety of complex vortex shear banding phenomena can be realized. A single row of pinning sites is removed from a square pinning array. Shear banding effects arise when vortex motion in the pin-free channel nucleates motion of vortices in the surrounding pinned regions, creating discrete steps in the vortex velocity profile away from the channel. Near the global depinning transition, the width of the band of moving vortices undergoes oscillations or fluctuations that can span the entire system. We use simulations to show that these effects should be observable in the transport properties of the system. Similar large oscillations and shear banding effects are known to occur for sheared complex fluids in which different dynamical phases coexist.

  1. Vortex combustor for low NOx emissions when burning lean premixed high hydrogen content fuel

    DOE Patents [OSTI]

    Steele, Robert C. (Woodinville, WA); Edmonds, Ryan G. (Renton, WA); Williams, Joseph T. (Kirkland, WA); Baldwin, Stephen P. (Winchester, MA)

    2009-10-20T23:59:59.000Z

    A trapped vortex combustor. The trapped vortex combustor is configured for receiving a lean premixed gaseous fuel and oxidant stream, where the fuel includes hydrogen gas. The trapped vortex combustor is configured to receive the lean premixed fuel and oxidant stream at a velocity which significantly exceeds combustion flame speed in a selected lean premixed fuel and oxidant mixture. The combustor is configured to operate at relatively high bulk fluid velocities while maintaining stable combustion, and low NOx emissions. The combustor is useful in gas turbines in a process of burning synfuels, as it offers the opportunity to avoid use of diluent gas to reduce combustion temperatures. The combustor also offers the possibility of avoiding the use of selected catalytic reaction units for removal of oxides of nitrogen from combustion gases exiting a gas turbine.

  2. HIGH-POWER TURBODRILL AND DRILL BIT FOR DRILLING WITH COILED TUBING

    SciTech Connect (OSTI)

    Robert Radtke; David Glowka; Man Mohan Rai; David Conroy; Tim Beaton; Rocky Seale; Joseph Hanna; Smith Neyrfor; Homer Robertson

    2008-03-31T23:59:59.000Z

    Commercial introduction of Microhole Technology to the gas and oil drilling industry requires an effective downhole drive mechanism which operates efficiently at relatively high RPM and low bit weight for delivering efficient power to the special high RPM drill bit for ensuring both high penetration rate and long bit life. This project entails developing and testing a more efficient 2-7/8 in. diameter Turbodrill and a novel 4-1/8 in. diameter drill bit for drilling with coiled tubing. The high-power Turbodrill were developed to deliver efficient power, and the more durable drill bit employed high-temperature cutters that can more effectively drill hard and abrasive rock. This project teams Schlumberger Smith Neyrfor and Smith Bits, and NASA AMES Research Center with Technology International, Inc (TII), to deliver a downhole, hydraulically-driven power unit, matched with a custom drill bit designed to drill 4-1/8 in. boreholes with a purpose-built coiled tubing rig. The U.S. Department of Energy National Energy Technology Laboratory has funded Technology International Inc. Houston, Texas to develop a higher power Turbodrill and drill bit for use in drilling with a coiled tubing unit. This project entails developing and testing an effective downhole drive mechanism and a novel drill bit for drilling 'microholes' with coiled tubing. The new higher power Turbodrill is shorter, delivers power more efficiently, operates at relatively high revolutions per minute, and requires low weight on bit. The more durable thermally stable diamond drill bit employs high-temperature TSP (thermally stable) diamond cutters that can more effectively drill hard and abrasive rock. Expectations are that widespread adoption of microhole technology could spawn a wave of 'infill development' drilling of wells spaced between existing wells, which could tap potentially billions of barrels of bypassed oil at shallow depths in mature producing areas. At the same time, microhole coiled tube drilling offers the opportunity to dramatically cut producers' exploration risk to a level comparable to that of drilling development wells. Together, such efforts hold great promise for economically recovering a sizeable portion of the estimated remaining shallow (less than 5,000 feet subsurface) oil resource in the United States. The DOE estimates this U.S. targeted shallow resource at 218 billion barrels. Furthermore, the smaller 'footprint' of the lightweight rigs utilized for microhole drilling and the accompanying reduced drilling waste disposal volumes offer the bonus of added environmental benefits. DOE analysis shows that microhole technology has the potential to cut exploratory drilling costs by at least a third and to slash development drilling costs in half.

  3. Estimating dispersion from a tornado vortex and mesocyclone

    SciTech Connect (OSTI)

    Weber, A.H.; Hunter, C.H.

    1996-06-01T23:59:59.000Z

    Atmospheric dispersion modeling is required to ensure that a postulated breach in radionuclide storage containers at the Savannah River Site (SRS) from a tornado strike of Fujita-scale intensity F2 or higher will not result in an unacceptable dose to individuals. Fujita-scale tornado descriptions are included in Appendix A of this report. Dispersion models previously used at SRS for estimating dispersion following a tornado strike were developed by D.W. Pepper in 1975 (DP-1387, Dispersion of Small Particles) and H.R. Haynes and D.W. Taylor in 1983 (DPST-82-982, Estimating Doses from Tornado Winds). Research conducted in 1983 on the formation and evolution of tornadic thunderstorms has lead to a more complete understanding of the tornado vortex and associated persistent updraft and downdraft regions within the parent thunderstorm. To ensure that appropriate, contemporary methods are used for safety analysis, the Pepper model and the Haynes and Taylor model were evaluated with respect to current knowledge of circulations within tornadic thunderstorms. Pepper`s model is complex numerically but contains most of the desired physical parameterizations. Haynes and Taylor`s model is used with the Puff-Plume model (an emergency response model on the Weather INformation and Display System at SRS) and has provisions for radionuclide deposition and rainout. Haynes and Taylor assumed heavy rain following the tornado for a period of ten minutes, followed by a lighter rain for another ten minutes, then no rain for the period when the material is transported to 100 km downwind. However, neither model incorporates the effects of a nearby thunderstorm downdraft.

  4. Formation of multi-solitons and vortex bright solitons in Bose-condensed alkali-metal atoms

    E-Print Network [OSTI]

    Luca Salasnich

    2003-09-02T23:59:59.000Z

    Formation of multi-solitons and vortex bright solitons in Bose-condensed alkali-metal atoms is analyzed by using the nonpolynomial Schordinger equation. A train of bright solitons is obtained from an axially homogeneous Bose-Einstein condensate by a sudden change of the scattering length from repulsive to attractive. We derive an analytical expression for the number of bright solitons generated by using this mechanism. The formula generalizes a previous formula obtained with the 1D Gross-Pitaevskii equation. In the second part we consider vortex bright solitons, namely cigar-shaped bright solitons with a nonzero angular quantum number $k$ along the axial direction. By using a variational approach we determine the shape of vortex bright solitons, showing that the critical number of atoms for the collapse of the vortex soliton increases with a larger $k$. Finally we calculate monopole and quadrupole collective oscillations of these vortex bright solitons.

  5. alloy pressure tubes: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    employed by India during this CRP and Indias performance on flaw detection and sizing in pressure tube samples. Based on the analysis of inspection results, the most...

  6. Penetrameter positioner for bore-side radiography of tubes

    DOE Patents [OSTI]

    Davis, E.V.; Foster, B.E.

    1980-02-05T23:59:59.000Z

    A positioner is provided for placing plaque or wire penetrameters, as used in radiographic inspection, in close proximity with the inner wall of tubing at any desired location along the tubing. The positioner head carrying the penetrameter is inflatable whereby it is positioned in tte deflated condition, inflated to place the penetrameter against a weld to be inspected in the tubing wall, and then deflated during removal. If desired, the penetrameter holder may be used to center the radiographic source on the axis of the tube.

  7. Method Of Making Closed End Ceramic Fuel Cell Tubes

    DOE Patents [OSTI]

    Borglum, Brian P. (Edgewood, PA)

    2002-04-30T23:59:59.000Z

    A method of manufacturing closed end ceramic fuel cell tubes with improved properties and higher manufacturing yield is disclosed. The method involves bonding an unfired cap to a hollow unfired tube to form a compound joint. The assembly is then fired to net shape without subsequent machining. The resultant closed end tube is superior in that it provides a leak-tight seal and its porosity is substantially identical to that of the tube wall. The higher manufacturing yield associated with the present method decreases overall fuel cell cost significantly.

  8. Bore tube assembly for steam cooling a turbine rotor

    DOE Patents [OSTI]

    DeStefano, Thomas Daniel (Ballston Lake, NY); Wilson, Ian David (Clifton Park, NY)

    2002-01-01T23:59:59.000Z

    An axial bore tube assembly for a turbine is provided to supply cooling steam to hot gas components of the turbine wheels and return the spent cooling steam. A pair of inner and outer tubes define a steam supply passage concentric about an inner return passage. The forward ends of the tubes communicate with an end cap assembly having sets of peripheral holes communicating with first and second sets of radial tubes whereby cooling steam from the concentric passage is supplied through the end cap holes to radial tubes for cooling the buckets and return steam from the buckets is provided through the second set of radial tubes through a second set of openings of the end cap into the coaxial return passage. A radial-to-axial flow transitioning device, including anti-swirling vanes is provided in the end cap. A strut ring adjacent the aft end of the bore tube assembly permits axial and radial thermal expansion of the inner tube relative to the outer tube.

  9. Numerical study of Kelvin-Helmholtz instability by the point vortex method

    SciTech Connect (OSTI)

    Krasny, R.

    1983-12-01T23:59:59.000Z

    Rosenhead's classical point vortex numerical method for studying the evolution of a vortex sheet from analytic initial data (Kelvin-Helmholtz instability) is examined using the discrete Fourier analysis techniques of Sulem, Sulem and Frisch. One cause for the chaotic motion previously observed in computations using a large number of vortices is that short wavelength perturbations are introduced spuriously by finite precision arithmetic and become amplified by the model's dynamics. Methods for controlling this source of error are given and the results confirm the formation of a singularity in a finite time which was previously found by Moore and Meiron, Baker and Orszag using different techniques of analysis. A cusp forms in the vortex sheet strength at the critical time, explaining the onset of erratic particle motion in applications of the numerical methods of Van de Vooren and Fink and Soh to this problem. Unlike those methods, the point vortex approximation remains consistent at the critical time and we present the results of a long time calculation. The singularity is interpreted physically as a discontinuity in the strain rate along the vortex sheet and also as the start of roll up on a small scale. We numerically study some aspects of the dependence of the solution on the initial condition and find agreement with Moore's asymptotic relation between the initial amplitude and the critical time. For large initial amplitudes, two cusps form in the sheet strength, corresponding to double roll up. We explain why the Poincare recurrenc theorem does not imply that the sheet will eventually unroll. Our results suggest that beyond the critical time, the vortex sheet becomes a spiral with infinite arclength although we have doubts about the approximation's accuracy in that regime. 36 references, 30 figures, 3 tables.

  10. The effects of a jet on vortex breakdown over a sharp leading-edge delta wing

    E-Print Network [OSTI]

    Maynard, Ian Kenneth

    1985-01-01T23:59:59.000Z

    THE EFFECTS OF A JET ON VORTEX BREAKDOWN OVER A SHARP LEADING-EDGE DELTA WING A Thesis Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December 1985... Major Subject: Aerospace Engineering THE EFFECTS OF A JET ON VORTEX BREAKDOWN OVER A SHARP LEADING-EDGE DELTA WING A Thesis by IAN KENNETH MAYNARD Approved as to style and content by: Cyrus Ostowar (Chairman of Committee) Stan J Miley (M er...

  11. Streamline topology and dilute particle dynamics in a Karman vortex street flow

    E-Print Network [OSTI]

    Wu, Z B

    2003-01-01T23:59:59.000Z

    Three types of streamline topology in a Karman vortex street flow are shown under the variation of spatial parameters. For the motion of dilute particles in the K\\'arm\\'an vortex street flow, there exist a route of bifurcation to a chaotic orbit and more attractors in a bifurcation diagram for the proportion of particle density to fluid density. Along with the increase of spatial parameters in the flow filed, the bifurcation process is suspended, as well as more and more attractors emerge. In the motion of dilute particles, a drag term and gravity term dominate and result in the bifurcation phenomenon.

  12. Glass heat pipe evacuated tube solar collector

    DOE Patents [OSTI]

    McConnell, Robert D. (Lakewood, CO); Vansant, James H. (Tracy, CA)

    1984-01-01T23:59:59.000Z

    A glass heat pipe is adapted for use as a solar energy absorber in an evacuated tube solar collector and for transferring the absorbed solar energy to a working fluid medium or heat sink for storage or practical use. A capillary wick is formed of granular glass particles fused together by heat on the inside surface of the heat pipe with a water glass binder solution to enhance capillary drive distribution of the thermal transfer fluid in the heat pipe throughout the entire inside surface of the evaporator portion of the heat pipe. Selective coatings are used on the heat pipe surface to maximize solar absorption and minimize energy radiation, and the glass wick can alternatively be fabricated with granular particles of black glass or obsidian.

  13. Project Implementation Seminar Series: Creating a Climate for Successful Project Implementation, December 9, 2009

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreakingMay 2015 < prev next >PresentationsNow LEADER Web Conference 1 Project

  14. New tube bundle heat transfer correlations and flow regime maps for a Once Through Steam Generator 

    E-Print Network [OSTI]

    Blanchat, Thomas Kevin

    1988-01-01T23:59:59.000Z

    Support Group for their many helpful discussions and comments throughout this project. I would like to thank Mr. Richard Wagner at EGgrG, Idaho, for his patient explanations of the mechanics of the RELAP5/MOD2 code which enabled me to perform the code... completed which allow the user to input the pitch and tube o. d. for the system. Predicted RELAP5/MOD2 heat transfer coefficients from correlations have been reviewed for single phase liquid convection, subcooled, and saturated nu- cleate boiling...

  15. Variable-energy drift-tube linear accelerator

    DOE Patents [OSTI]

    Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM); Potter, James M. (Los Alamos, NM); Stovall, James E. (Los Alamos, NM)

    1984-01-01T23:59:59.000Z

    A linear accelerator system includes a plurality of post-coupled drift-tubes wherein each post coupler is bistably positionable to either of two positions which result in different field distributions. With binary control over a plurality of post couplers, a significant accumlative effect in the resulting field distribution is achieved yielding a variable-energy drift-tube linear accelerator.

  16. Analysis of tubes filled with charged electron gas

    E-Print Network [OSTI]

    Stefan Karrmann

    2011-02-24T23:59:59.000Z

    We show that tubes filled with electron gas, as presented by A.Bolonkin, are not possible with current materials. First, the pressure of the charges on the outer surface cancel almost all of the electrostatic pressure of the inner electrons. Second, due to the mutually repulsion most of the electrons are in the outmost shell of the tube and not individually free.

  17. Aquifer Sampling Tube Results for Fiscal Year 2003

    SciTech Connect (OSTI)

    Hartman, Mary J.; Peterson, Robert E.

    2003-10-27T23:59:59.000Z

    This report presents and discusses results of the fiscal year 2003 sampling event associated with aquifer tubes along the Columbia River in the northern Hanford Site. Aquifer tube data help define the extent of groundwater contamination near the river, determine vertical variations in contamination, monitor the performance of interim remedial actions near the river, and support impact studies.

  18. Drift tube suspension for high intensity linear accelerators

    DOE Patents [OSTI]

    Liska, D.J.; Schamaun, R.G.; Clark, D.C.; Potter, R.C.; Frank, J.A.

    1980-03-11T23:59:59.000Z

    The disclosure relates to a drift tube suspension for high intensity linear accelerators. The system comprises a series of box-sections girders independently adjustably mounted on a linear accelerator. A plurality of drift tube holding stems are individually adjustably mounted on each girder.

  19. The effect of roughness on aerosol deposition in tubes

    E-Print Network [OSTI]

    Chavez, Mario Cesar

    1997-01-01T23:59:59.000Z

    Experimental measurements of simulated roughness within tubes and the subsequent aerosol penetration performance through these tubes were conducted for a aerosol particle size range of 5 nm to 20 nm and a flow rate range of 28 L/min to 169.9 L...

  20. Heat exchanger with leak detecting double wall tubes

    SciTech Connect (OSTI)

    Bieberbach, George (Tampa, FL); Bongaards, Donald J. (Seminole, FL); Lohmeier, Alfred (Tampa, FL); Duke, James M. (St. Petersburg, all of, FL)

    1981-01-01T23:59:59.000Z

    A straight shell and tube heat exchanger utilizing double wall tubes and three tubesheets to ensure separation of the primary and secondary fluid and reliable leak detection of a leak in either the primary or the secondary fluids to further ensure that there is no mixing of the two fluids.

  1. Iterative Learning Control Applications to High Power Microwave Tubes

    E-Print Network [OSTI]

    high­peak power microwave (HPM) sources typically operate in the single shot regime because commercial HPM systems that operate at modest repetition rates, two examples of which include a system based is then to implement the control algorithms on a physical tube in order to build a ``smart tube'' HPM source. By smart

  2. Iterative Learning Control Applications to High Power Microwave Tubes

    E-Print Network [OSTI]

    high-peak power microwave (HPM) sources typically operate in the single shot regime because commercial HPM systems that operate at modest repetition rates, two examples of which include a system based is then to implement the control algorithms on a physical tube in order to build a "smart tube" HPM source. By smart

  3. Characterization of Bead Trajectories Through the Draft Tube of a Turbine Physical Model.

    SciTech Connect (OSTI)

    Weiland, Mark A.; Mueller, Robert P.; Carlson, Thomas J.; Deng, Zhiquan; McKinstry, Craig A.

    2005-02-18T23:59:59.000Z

    Using high-speed video imaging, trajectories, and kinematics of beads passing below the turbine runner and through the draft tube region of the 1:25 scale model of a single turbine unit from Bonneville Dam powerhouse 1 were collected from May 6-9, 2003 at U.S. Army Corps of Engineers (USACE) Environmental Research and Development Center (ERDC) in Vicksburg, MS. An individual camera was used to produce 2-dimensional trajectories and paired cameras with overlapping fields of view were used to produce 3-dimension trajectories of near neutrally buoyant beads as they passed through the draft tube region of the turbine model. Image data was collected at two turbine operating levels, lower 1% efficiency and maximum rated output for beads released mid-depth into the turbine intake from each of the three gatewell slots. The purpose of this study was to determine the feasibility of using video imaging to track the trajectories of beads through the draft tube of turbine physical models and from the trajectories calculate the kinematics of the bead trajectory and the beads response to turbulence in the model. This project is part of a research program supported by the U.S. Department of Energy Advanced Hydropower Turbine System Program (AHTS) who's goal is to increase the operating potential of hydroelectric facilities while also reducing the reducing the risk of injury and death to fish as they pass through the turbines.

  4. Status Report on Studies of Recovery Boiler Composite Floor Tube Cracking

    SciTech Connect (OSTI)

    Eng, P.; Frederick, L.A.; Hoffmann, C.M.; Keiser, J.R.; Mahmood, J.; Maziasz, P.J.; Prescott, R.; Sarma, G.B.; Singbeil, D.L.; Singh, P.M.; Swindeman, R.W.; Wang, X.-L.

    1999-09-12T23:59:59.000Z

    Cracking of the stainless steel layer of co-extruded 304L stainless steel/SA210 Gd A 1 carbon steel black liquor recovery boiler floor tubes has been identified as one of the most serious material problems in the pulp and paper industry. A DOE-funded study was initiated in 1995 with the goal of determining the cause of and possible solutions to this cracking problem. These studies have characterized tube cracking as well as the chemical and thermal environment and stress state of floor tubes. Investigations of possible cracking mechanisms indicate that stress corrosion cracking rather than thermal fatigue is a more likely cause of crack initiation. The cracking mechanism appears to require the presence of hydrated sodium sulfide and is most likely active during shut-downs and/or start-ups. Based on these results and operating experience, certain alloys appear to be more resistant than others to cracking in the floor environment, and certain operating practices appear to significantly lessen the likelihood of cracking. This report is the latest in a series of progress reports presented on this project.

  5. Effects of hydrophilic surface treatment on evaporation heat transfer at the outside wall of horizontal tubes

    E-Print Network [OSTI]

    Kim, Ho-Young

    of horizontal tubes H.-Y. Kim a , B.H. Kang b,* a Thermal/Flow Control Research Center, Korea Institute hydrophilic treatment induces film flow on the tubes while sessile drops are formed on untreated tubes liquid film on horizontal low-finned tubes is 60­100% more efficient than that on plain tubes. When

  6. Hierarchical Part-Based Detection of 3D Flexible Tubes: Application to CT Colonoscopy

    E-Print Network [OSTI]

    Barbu, Adrian

    operations (region growing). Fig. 1. The rectal tubes are flexible and have variable shape and appearance and tube segments to the whole flexible tube. To increase the speed of the algorithm, can- didate parts are generated using a voting strategy. The detected tube segments are combined into a flexible tube using

  7. Magnesium Projects

    Broader source: Energy.gov (indexed) [DOE]

    cyberinfrastructure projects and will be augmented by original research in Computer Science and Software Engineering towards the creation of large, distributed, autonomic and...

  8. Project Construction

    Broader source: Energy.gov [DOE]

    Integrating renewable energy into Federal new construction or major renovations requires effective structuring of the construction team and project schedule. This overview discusses key construction team considerations for renewable energy as well as timing and expectations for the construction phase. The project construction phase begins after a project is completely designed and the construction documents (100%) have been issued. Construction team skills and experience with renewable energy technologies are crucial during construction, as is how the integration of renewable energy affects the project construction schedule.

  9. Effect of asymmetric axial strain on the behavior of the juncture vortex system

    E-Print Network [OSTI]

    Trosper, Jeffrey Randall

    1994-01-01T23:59:59.000Z

    The objective of this research was to investigate the behavior of the vortex formed in a wing-body juncture in a water tunnel flow. The wing-body juncture was created by mounting a symmetrical airfoil with an elliptical leading edge normal to a flat...

  10. A Lagrangian approach to identifying vortex pinch-off Clara O'Farrell1

    E-Print Network [OSTI]

    Dabiri, John O.

    A Lagrangian approach to identifying vortex pinch-off Clara O'Farrell1 and John O. Dabiri2 1 Control and Dynamical Systems, California Institute of Technology, Pasadena, California 91125, USA 2 Graduate Aeronautical Laboratories and Bioengineering, California Institute of Technology, Pasadena

  11. Crown copyright Met Office Hurricane dynamics: on the role of Vortex Rossby Waves (VRWs).

    E-Print Network [OSTI]

    © Crown copyright Met Office Hurricane dynamics: on the role of Vortex Rossby Waves (VRWs). Gilbert of numerical weather prediction: hurricanes, typhoons and tropical cyclones · Hurricane intensity · Conclusion #12;© Crown copyright Met Office Hurricane Juan, 28 September 2003, Halifax 75°N 110°W 10°E5°N

  12. Indirect Combustion Noise: Experimental Investigation of the Vortex Sound Generation in a Choked

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Indirect Combustion Noise: Experimental Investigation of the Vortex Sound Generation in a Choked-27 April 2012, Nantes, France 2315 #12;Combustion noise in gas turbines consists of direct noise related to the unsteady combustion process itself and indirect noise. As known, indirect noise is produced when entropy

  13. Observations of wave-generated vortex ripples on the North Carolina continental shelf

    E-Print Network [OSTI]

    Kirby, James T.

    October 2002. [1] Sand ripples with wavelengths between 0.5 and 3 m were observed on the bottom across, 1882; Forel, 1883; Dingler, 1974; Vincent and Osborne, 1993; Gallagher et al., 1998; Traykovski et al ripples'' by Bagnold [1946], exert a much larger drag on the flow than friction on sand grains. Vortex

  14. Simulation of vortex sheet roll-up: chaos, azimuthal waves, ring merger

    E-Print Network [OSTI]

    Krasny, Robert

    Simulation of vortex sheet roll-up: chaos, azimuthal waves, ring merger Robert KRASNY1 , Keith-1109 USA krasny@umich.edu National Center for Atmospheric Research, Climate andGlobal Dynamics Boulder, axisymmetric, and three- dimensional flow Krasny &Nitsche 2001; Lindsay & Krasny 2001. Vor- tex sheet

  15. On the bifurcation structure of axisyrnmetric vortex breakdown in a constricted pipe

    E-Print Network [OSTI]

    Lopez, John M.

    On the bifurcation structure of axisyrnmetric vortex breakdown in a constricted pipe J. M. Lopez Department of Mathematics and Earth SystemScienceCenter;The PennsylvaniaState University, Universiv Park, Pennsylvania 16802 (Received 5 April 1994; accepted 20 July 1994) The bifurcation structure is presented

  16. Complex Langevin simulation of quantum vortex nucleation in the Bose-Einstein condensate

    E-Print Network [OSTI]

    Tomoya Hayata; Arata Yamamoto

    2014-11-19T23:59:59.000Z

    The ab-initio simulation of quantum vortex nucleation in the Bose-Einstein condensate is performed by adopting the complex Langevin techniques. We simulate the two-component boson field theory at a finite chemical potential under rotation. In the superfluid phase, vortices are generated above a critical angular velocity and the circulation is clearly quantized even in the presence of quantum fluctuations.

  17. Wavelet analysis of vortex breakdown Jori E. Ruppert-Felsot1

    E-Print Network [OSTI]

    École Normale Supérieure

    Wavelet analysis of vortex breakdown Jori E. Ruppert-Felsot1 , Marie Farge1 , and Philippe the experimentally mea- sured flow field using orthogonal wavelets to observe the time evolution of the bursting. The discrete wavelet transform is used to separate the flow field into a coherent component, capturing

  18. 2094 OPTICS LETTERS / Vol. 28, No. 21 / November 1, 2003 Fundamental and vortex solitons in a

    E-Print Network [OSTI]

    Yang, Jianke

    2094 OPTICS LETTERS / Vol. 28, No. 21 / November 1, 2003 Fundamental and vortex solitons in a two-dimensional optical lattice Jianke Yang Department of Mathematics and Statistics, University of Vermont, Burlington-dimensional optically induced waveguide array are reported. In the strong localization regime the fundamental soliton

  19. Vortex Ring Interaction with a Particle Layer: Implications for Sediment Transport

    E-Print Network [OSTI]

    Dalziel, Stuart

    resuspension has been studied much less. This is an important mechanism, however, as it represents an integral conducted to study particle resuspension by vortex rings colliding with a particle bed. The dynamics at the resuspension onset are investigated, showing that the deformable particle bed resembles a free slip boundary

  20. Reduced gravity rankine cycle design and optimization with passive vortex phase separation 

    E-Print Network [OSTI]

    Supak, Kevin Robert

    2009-05-15T23:59:59.000Z

    Interphase Transport Phenomena kW(e) Kilowatts-Electric MVS Microgravity Vortex Separator ORNL Oak Ridge National Laboratory SNAP Systems For Nuclear Auxiliary Power MPRE Medium Power Reactor Experiment RFMD Rotary Fluid Management Device RPM...............................................................................................3 History of Space Rankine Cycle Development .....................................6 ORNL Rankine Cycle Design..............................................................10 Space Rankine Cycle Components...

  1. Reduced gravity Rankine cycle system design and optimization study with passive vortex phase separation 

    E-Print Network [OSTI]

    Supak, Kevin Robert

    2008-10-10T23:59:59.000Z

    Interphase Transport Phenomena kW(e) Kilowatts-Electric MVS Microgravity Vortex Separator ORNL Oak Ridge National Laboratory SNAP Systems For Nuclear Auxiliary Power MPRE Medium Power Reactor Experiment RFMD Rotary Fluid Management Device RPM...............................................................................................3 History of Space Rankine Cycle Development .....................................6 ORNL Rankine Cycle Design..............................................................10 Space Rankine Cycle Components...

  2. Vortex Liquid Crystals in Anisotropic Type II Superconductors E.W. Carlson,1,2

    E-Print Network [OSTI]

    Carlson, Erica

    Vortex Liquid Crystals in Anisotropic Type II Superconductors E.W. Carlson,1,2 A. H. Castro Neto,1 September 2002; published 25 February 2003) In an isotropic type II superconductor in a moderate magnetic been much interest in high tem- perature superconductors in a magnetic field. Various ex- periments

  3. Two regimes of vortex penetration into platelet-shaped type-II superconductors

    SciTech Connect (OSTI)

    Brandt, E. H. [Max-Planck-Institut fuer Metallforschung (Germany)] [Max-Planck-Institut fuer Metallforschung (Germany); Mikitik, G. P., E-mail: mikitik@ilt.kharkov.ua [Ukrainian Academy of Sciences, Verkin Institute for Low Temperature Physics and Engineering (Ukraine); Zeldov, E. [Weizmann Institute of Science, Department of Condensed Matter Physics (Israel)] [Weizmann Institute of Science, Department of Condensed Matter Physics (Israel)

    2013-09-15T23:59:59.000Z

    Vortex penetration into a thin superconducting strip of a rectangular cross section is considered at an increasing applied magnetic field H{sub a}, taking an interplay between the Bean-Livingston and the geometric barriers in the sample into account. We calculate the magnetic field H{sub p} at which the penetration begins and show that two regimes of vortex penetration are possible. In the first regime, vortices appearing at the corners of the strip at H{sub a} = H{sub p} immediately move to its center, where a vortex dome starts to develop. In the second regime, the penetration occurs in two stages. In the first stage, at H{sub a} < H{sub p}, tilted vortices penetrate into the edge regions of the strip, where novel domes are shown to be formed at the top, bottom, and lateral surfaces. In the second stage, at H{sub a} = H{sub p}, the vortex propagation to the center becomes possible. The difference between the regimes manifests itself in slightly different dependences of the magnetic moment of the strip on H{sub a}.

  4. Origin of Reversed Vortex Ratchet Motion W. Gillijns, A. V. Silhanek, and V. V. Moshchalkov

    E-Print Network [OSTI]

    Moshchalkov, Victor V.

    Origin of Reversed Vortex Ratchet Motion W. Gillijns, A. V. Silhanek, and V. V. Moshchalkov INPAC. This rectified motion of particles, known as a rocked ratchet, is basically the result of the broken spatial that the particles (flux lines) cannot be regarded as independent entities leads to a far richer ratchet motion

  5. Evolution of an initially columnar vortex terminating normal to a no-slip wall

    E-Print Network [OSTI]

    Lopez, John M.

    Èdewadt-type spatially oscillatory boundary layer within the core region and a potential-like vortex boundary layer at large radii. The toroidal structure results from the interaction between these two boundary layers's theo- retical study only applied to the boundary layer formed away from the core, as have most other

  6. BAROCLINIC VORTICITY PRODUCTION IN PROTOPLANETARY DISKS. II. VORTEX GROWTH AND LONGEVITY

    E-Print Network [OSTI]

    Julien, Keith

    BAROCLINIC VORTICITY PRODUCTION IN PROTOPLANETARY DISKS. II. VORTEX GROWTH AND LONGEVITY Mark R -- instabilities -- methods: numerical -- solar system: formation -- turbulence Online material: color figures 1 the surface. Thus, the potential energy of the tilted isopycnals is converted into the kinetic energy

  7. Vortex avalanches with robust statistics observed in superconducting niobium E. Altshuler,1,2

    E-Print Network [OSTI]

    Zeldov, Eli

    Vortex avalanches with robust statistics observed in superconducting niobium E. Altshuler,1,2 T. H topography of superconducting niobium samples as the external field is slowly increased. The avalanche size in Ref. 11, was quite limited, being based on only a few hundred events. Nowak et al.12 studied niobium

  8. Vortex-Pair Dynamics in Anisotropic Bistable Media: A Kinematic Approach Aric Hagberg1

    E-Print Network [OSTI]

    Hagberg, Aric

    Vortex-Pair Dynamics in Anisotropic Bistable Media: A Kinematic Approach Aric Hagberg1 and Ehud typically evolves into rotating spiral waves. In an anisotropic system, instead of spiral waves, the vortices can form wave fragments that propagate with a constant speed in a given direction determined

  9. Particle resuspension by an impacting vortex ring RICK J. MUNRO & STUART B. DALZIEL

    E-Print Network [OSTI]

    Dalziel, Stuart

    Particle resuspension by an impacting vortex ring RICK J. MUNRO & STUART B. DALZIEL Department results from a set of visualization experiments conducted to analyse the hydrodynamic resuspension of particles from a thick horizontal sediment layer. The mechanism employed to produce the resuspension

  10. Resuspension onset and crater erosion by a vortex ring interacting with a particle layer

    E-Print Network [OSTI]

    Dalziel, Stuart

    Resuspension onset and crater erosion by a vortex ring interacting with a particle layer N. Bethke://pof.aip.org/features/most_downloaded Information for Authors: http://pof.aip.org/authors #12;PHYSICS OF FLUIDS 24, 063301 (2012) Resuspension onset layer. The flow dynamics during the onset of particle resuspension are analysed using particle image

  11. Sediment resuspension and erosion by vortex rings R. J. Munro,1,a

    E-Print Network [OSTI]

    Dalziel, Stuart

    Sediment resuspension and erosion by vortex rings R. J. Munro,1,a N. Bethke,2 and S. B. Dalziel2 1; accepted 26 January 2009; published online 8 April 2009 Particle resuspension and erosion induced-ring propagation speed. The critical conditions for resuspension whereby particles are only just resuspended were

  12. Fluid Dynamics Research 33 (2003) 333356 Leapfrogging vortex rings: Hamiltonian structure, geometric

    E-Print Network [OSTI]

    Shashikanth, Banavara N.

    2003-01-01T23:59:59.000Z

    Fluid Dynamics Research 33 (2003) 333­356 Leapfrogging vortex rings: Hamiltonian structure that if the rings are modeled as coaxial circular ÿlaments, their dynamics and Hamil- tonian structure is derivable of Mechanical Engineering, New Mexico State University, Las Cruces, NM 88003, USA b Control and Dynamical

  13. Vortex-peak interaction and lattice shape in rotating two-component Bose-Einstein condensates

    E-Print Network [OSTI]

    Wei, Jun-cheng

    Vortex-peak interaction and lattice shape in rotating two-component Bose-Einstein condensates: November 28, 2011) When a two component Bose-Einstein condensate is placed into rotation, a lattice component condensate is set into rotation, topological defects of both order parameters are created, which

  14. Formation and Decay of Vortex Lattices in Bose-Einstein Condensates at Finite Temperatures

    E-Print Network [OSTI]

    Formation and Decay of Vortex Lattices in Bose-Einstein Condensates at Finite Temperatures Gaseous Bose-Einstein condensates (BEC) are a testbed for many-body theory. Recently, rotating condensates was observed non-destructively by monitoring the centrifugal distortions of the rotating condensate

  15. ccsd00003161, Vortex patterns in a fast rotating Bose-Einstein condensate

    E-Print Network [OSTI]

    . Furthermore we restrict our analysis to the case of a two-dimensional gas in the xy plane, assumingccsd­00003161, version 1 ­ 26 Oct 2004 Vortex patterns in a fast rotating Bose-Einstein condensate, France (Dated: October 26, 2004) For a fast rotating condensate in a harmonic trap, we investigate

  16. Spacetime Defects von K\\'arm\\'an vortex street like configurations

    E-Print Network [OSTI]

    Letelier, P S

    2001-01-01T23:59:59.000Z

    A special arrangement of spinning strings with dislocations similar to a von K\\'arm\\'an vortex street is studied. We numerically solve the geodesic equations for the special case of a test particle moving along twoinfinite rows of pure dislocations and also discuss the case of pure spinning defects.

  17. Theory of vortex crystal formation in two-dimensional turbulence* Dezhe Z. Jin

    E-Print Network [OSTI]

    California at San Diego, University of

    Theory of vortex crystal formation in two-dimensional turbulence* Dezhe Z. Jin and Daniel H. E are symmetric arrays of strong vortices within a background of weaker vorticity. This paper presents a theory, a theory is advanced that allows us to predict from the initial conditions the approximate number

  18. Proceedings: International Conference on Boiler Tube Failures and Heat Recovery Steam Generator (HRSG) Tube Failures and Inspections

    SciTech Connect (OSTI)

    None

    2002-10-01T23:59:59.000Z

    Tube failures remain the leading cause of availability loss in conventional fossil plants and combined cycle/heat recovery steam generator (HRSG) plants. These conference proceedings address state-of-the-art practices and techniques worldwide for understanding and reducing tube failures.

  19. ORIGIN OF MACROSPICULE AND JET IN POLAR CORONA BY A SMALL-SCALE KINKED FLUX TUBE

    SciTech Connect (OSTI)

    Kayshap, P.; Srivastava, Abhishek K. [Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Nainital 263129 (India); Murawski, K. [Group of Astrophysics, UMCS, ul. Radziszewskiego 10, 20-031 Lublin (Poland); Tripathi, Durgesh, E-mail: pradeep.kashyap@aries.res.in, E-mail: aks@aries.res.in, E-mail: kmur@kft.umcs.lublin.pl, E-mail: durgesh@iucaa.ernet.in [Inter-University Centre for Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India)

    2013-06-10T23:59:59.000Z

    We report an observation of a small-scale flux tube that undergoes kinking and triggers the macrospicule and a jet on 2010 November 11 in the north polar corona. The small-scale flux tube emerged well before the triggering of the macrospicule and as time progresses the two opposite halves of this omega-shaped flux tube bent transversely and approach each other. After {approx}2 minutes, the two approaching halves of the kinked flux tube touch each other and an internal reconnection as well as an energy release takes place at the adjoining location and a macrospicule was launched which goes up to a height of 12 Mm. Plasma begins to move horizontally as well as vertically upward along with the onset of the macrospicule and thereafter converts into a large-scale jet in which the core denser plasma reaches up to {approx}40 Mm in the solar atmosphere with a projected speed of {approx}95 km s{sup -1}. The fainter and decelerating plasma chunks of this jet were also seen up to {approx}60 Mm. We perform a two-dimensional numerical simulation by considering the VAL-C initial atmospheric conditions to understand the physical scenario of the observed macrospicule and associated jet. The simulation results show that reconnection-generated velocity pulse in the lower solar atmosphere steepens into slow shock and the cool plasma is driven behind it in the form of macrospicule. The horizontal surface waves also appeared with shock fronts at different heights, which most likely drove and spread the large-scale jet associated with the macrospicule.

  20. Condensation of Refrigerant-11 on the outside of horizontal and inclined enhanced tubes

    SciTech Connect (OSTI)

    Domingo, N.

    1982-12-01T23:59:59.000Z

    Heat transfer condensation tests with Refrigerant-11 were performed on the outside of a smooth tube and a variety of enhanced tubes oriented horizontally and at various tube inclinations. One smooth tube and seven enhanced (externally fluted, roped, spiraled, and externally finned) tubes of 2.54-cm (1-in.) nominal outside diameter and 1.17-m (4-ft) length were tested. Several of the tested tubes featured internal enhanced geometries, which were caused by the heat transfer enhancing geometry on the tube's external surface. Condensing heat transfer coefficients are reported as composite coefficients, which combine the resistance of the condensing film and the tube wall, and are based on total tube outside surface area. Results show that in the horizontal condensing mode, the rank order (best to worst) of the tube geometries tested was spiral-shaped tubes, rope-shaped tubes, smooth tube, externally finned tube, and externally fluted tube. For a spiral-shaped tube, horizontal composite coefficients were up to 2.0 times the corresponding horizontal smooth tube values. For tilt angles greater than or equal to 60/sup 0/ from the horizontal, the condensing performance of the externally fluted tube was best of all the tubes tested.

  1. Projection Radiography Polytechnic University, Brooklyn, NY 11201

    E-Print Network [OSTI]

    Suel, Torsten

    : · The produced x-ray power Px (in[W]) is given by: ­ Material constant k = 1.1×10-9 for Tungsten (Z=74). 2 tube tubeI V I 2 / : x-ray production efficiency x tube tube tube tube tube x tube tube P k Z V I kZ V P P P sizes) · Anode ­ Tungsten, Zw = 74, Tmelt = 2250 ºC ­ Embedded in copper for heat dissipation ­ Angled

  2. Mining data on usage of electronic nicotine delivery systems (ENDS) from YouTube videos

    E-Print Network [OSTI]

    Talbot, Prue

    2013-01-01T23:59:59.000Z

    systems (ENDS) from YouTube videos My Hua, Henry Yip, PrueENDS) and conventional cigarettes in YouTube videos.Methods Video data from YouTube videos were analysed to

  3. Benchmarking gyrokinetic simulations in a toroidal flux-tube

    SciTech Connect (OSTI)

    Chen, Y.; Parker, S. E.; Wan, W. [University of Colorado at Boulder, Boulder, Colorado 80309 (United States)] [University of Colorado at Boulder, Boulder, Colorado 80309 (United States); Bravenec, R. [Fourth-State Research, Austin, Texas 78704 (United States)] [Fourth-State Research, Austin, Texas 78704 (United States)

    2013-09-15T23:59:59.000Z

    A flux-tube model is implemented in the global turbulence code GEM [Y. Chen and S. E. Parker, J. Comput. Phys. 220, 839 (2007)] in order to facilitate benchmarking with Eulerian codes. The global GEM assumes the magnetic equilibrium to be completely given. The initial flux-tube implementation simply selects a radial location as the center of the flux-tube and a radial size of the flux-tube, sets all equilibrium quantities (B, ?B, etc.) to be equal to the values at the center of the flux-tube, and retains only a linear radial profile of the safety factor needed for boundary conditions. This implementation shows disagreement with Eulerian codes in linear simulations. An alternative flux-tube model based on a complete local equilibrium solution of the Grad-Shafranov equation [J. Candy, Plasma Phys. Controlled Fusion 51, 105009 (2009)] is then implemented. This results in better agreement between Eulerian codes and the particle-in-cell (PIC) method. The PIC algorithm based on the v{sub ||}-formalism [J. Reynders, Ph.D. dissertation, Princeton University, 1992] and the gyrokinetic ion/fluid electron hybrid model with kinetic electron closure [Y. Chan and S. E. Parker, Phys. Plasmas 18, 055703 (2011)] are also implemented in the flux-tube geometry and compared with the direct method for both the ion temperature gradient driven modes and the kinetic ballooning modes.

  4. Residual stresses in weld overlay tubes: A finite element study

    SciTech Connect (OSTI)

    Taljat, B.; Zacharia, T.; Wang, X.L.; Keiser, J.R. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.; Feng, Z. [Edison Welding Inst., Columbus, OH (United States); Jirinec, M.J. [Welding Services, Inc., Norcross, GA (United States)

    1997-01-03T23:59:59.000Z

    Residual stresses and strains in a tube with circumferential weld overlay were analyzed by the finite element (FE) method. The objective of this work was to develop and verify a FE model, to determine the magnitude and distribution of residual stresses in the weld overlay tube, and to evaluate the significance of two contributing factors to residual stress: (1) difference in material properties between tube and weld material, and (2) thermal gradients in the weld. An axisymmetric FE model was developed to simulate the circumferential two-layer welding process of alloy 625 overlay on SA210 tube. The first layer was modeled as a gas metal arc welding process with filler metal, whereas the autogenous gas tungsten arc welding process was modeled for the second layer. Neutron diffraction technique was used to experimentally determine residual elastic strains in the weld overlay tube. Comparison with the FE results shows overall good agreement. Both the experimental and FE results show high compressive stresses at the inside tube surface and high tensile stresses in the weld overlay. This suggests that weld overlay may be used to relieve tensile or produce compressive stresses at the inside tube surface, which is significant for applications where crack initiation is found at the root pass of the joining weld.

  5. Coiled tubing deployed ESP works well for Shell in North Sea field

    SciTech Connect (OSTI)

    Watkins, P. [Centrilift, Aberdeen (United Kingdom); Stewart, D.

    1996-06-01T23:59:59.000Z

    What is believed to be the world`s first offshore coiled tubing deployed ESP system was installed by Centrilift, a Division of Baker Hughes Ltd., on Shell Expro`s Auk field Alpha platform in March 1995. After one year, the system is working well and is now viewed as a major step forward in alternative deployment methods for ESPs. Basic features of the system and project background are overviewed here. Shell U.K. Exploration and Production (Expro) operates in the UK Sector of the North Sea on behalf of Shell and Esso. Centrilift worked closely with Shell on this high-profile project and is active on several others, all aimed at reducing the operator`s cost for installing ESPs by using alternative deployment methods.

  6. Silver Peak Innovative Exploration Project

    Broader source: Energy.gov (indexed) [DOE]

    hyperspectral imaging for the discovery of blind geothermal resources * Coiled-tube drilling - Demonstrate coiled tube drilling in a geothermal environment 5 | US DOE Geothermal...

  7. The effect of charcoal tube geometry on breakthrough volume

    E-Print Network [OSTI]

    Strange, Jay B.

    1989-01-01T23:59:59.000Z

    on the breakthrough volume using parameters established by the National Institute for Occupational Safety and Health (NIOSH). Glass tubes with internal diameters of 2, 4 and 6 mm, each containing 100 mg of charcoal, were exposed to acetone concentrations... of approximately 1500, 750 and 375 ppm at flowrates of 200, 100 and 50 cc/min. The average bed lengths for the 2, 4 and 6 mm tubes were 57. 1, 14. 3 and 6. 3 mm respectively. Eighty-one hand packed charcoal tubes were used in twenty-seven experimental runs...

  8. Why Do Kraft Recovery Boiler Composite Floor Tubes Crack?

    SciTech Connect (OSTI)

    Keiser, J.R.

    2001-10-22T23:59:59.000Z

    Cracks were first reported in 1992 in co-extruded 304L stainless steel/SA210 Gd Al carbon steel floor tubes of North American black liquor recovery boilers. Since then, a considerable amount of information has been collected on the tube environment, crack characteristics, the stress state of the tubes, and the crack initiation and propagation mechanisms. These studies have identified both operating procedures that apparently can greatly lessen the likelihood of crack formation in the stainless steel layer and alternate materials that appear to be much more resistant to cracking than is 304L stainless.

  9. Composite Tube Trailer Design/Manufacturing Needs | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the YouTube platformBuildingCoalComplex Flow Workshop Report January 17-18,51429 Vol.

  10. Heat transfer from a finned circular tube and from a finned streamlined tube by forced convection

    E-Print Network [OSTI]

    Adams, David Michael

    1960-01-01T23:59:59.000Z

    Ilimansions P/J' " Units 4. oj. Air static pressure drop a r oas I!. VV' not ele Ai. r static pressure drop across tost section and test chambe. Air stat' pressure drop across t'est acct~ on Air static pressure drop across L lenSth of duct.... ty of water Mass of dry air flowing through nozzle and duct Mass of water flowing through test section Reynolds Number over test section Reynolds Number over finned circular tube based on D' Nusselt Number for Dimensions L2 Units Used 2...

  11. Contributions of the wall boundary layer to the formation of the counter-rotating vortex pair in transverse jets

    E-Print Network [OSTI]

    Schlegel, Fabrice

    Using high-resolution 3-D vortex simulations, this study seeks a mechanistic understanding of vorticity dynamics in transverse jets at a finite Reynolds number. A full no-slip boundary condition, rigorously formulated in ...

  12. Coiled tubing drilling with supercritical carbon dioxide

    DOE Patents [OSTI]

    Kolle , Jack J. (Seattle, WA)

    2002-01-01T23:59:59.000Z

    A method for increasing the efficiency of drilling operations by using a drilling fluid material that exists as supercritical fluid or a dense gas at temperature and pressure conditions existing at a drill site. The material can be used to reduce mechanical drilling forces, to remove cuttings, or to jet erode a substrate. In one embodiment, carbon dioxide (CO.sub.2) is used as the material for drilling within wells in the earth, where the normal temperature and pressure conditions cause CO.sub.2 to exist as a supercritical fluid. Supercritical carbon dioxide (SC--CO.sub.2) is preferably used with coiled tube (CT) drilling equipment. The very low viscosity SC--CO.sub.2 provides efficient cooling of the drill head, and efficient cuttings removal. Further, the diffusivity of SC--CO.sub.2 within the pores of petroleum formations is significantly higher than that of water, making jet erosion using SC--CO.sub.2 much more effective than water jet erosion. SC--CO.sub.2 jets can be used to assist mechanical drilling, for erosion drilling, or for scale removal. A choke manifold at the well head or mud cap drilling equipment can be used to control the pressure within the borehole, to ensure that the temperature and pressure conditions necessary for CO.sub.2 to exist as either a supercritical fluid or a dense gas occur at the drill site. Spent CO.sub.2 can be vented to the atmosphere, collected for reuse, or directed into the formation to aid in the recovery of petroleum.

  13. Project Manager

    Broader source: Energy.gov [DOE]

    A successful candidate in this position will serve as a project manager in the Fuel Cell Technologies Office in the DOE-EERE Office of Transportation responsible for a wide variety of highly...

  14. RENOTER Project

    Broader source: Energy.gov [DOE]

    Overview of French project on thermoelectric waste heat recovery for cars and trucks with focus on cheap, available, efficient, and sustainable TE materials, as well as efficient material integration and production process.

  15. Utilization of coal-water fuels in fire-tube boilers. Final report, October 1990--August 1994

    SciTech Connect (OSTI)

    Sommer, T.; Melick, T.; Morrison, D.

    1994-12-31T23:59:59.000Z

    The objective of this DOE sponsored project was to successfully fire coal-water slurry in a fire-tube boiler that was designed for oil/gas firing and establish a data base that will be relevant to a large number of existing installations. Firing slurry in a fire-tube configuration is a very demanding application because of the extremely high heat release rates and the correspondingly low furnace volume where combustion can be completed. Recognizing that combustion efficiency is the major obstacle when firing slurry in a fire-tube boiler, the program was focused on innovative approaches for improving carbon burnout without major modifications to the boiler. The boiler system was successfully designed and operated to fire coal-water slurry for extended periods of time with few slurry related operational problems. The host facility was a 3.8 million Btu/hr Cleaver-Brooks fire-tube boiler located on the University of Alabama Campus. A slurry atomizer was designed that provided outstanding atomization and was not susceptible to pluggage. The boiler was operated for over 1000 hours and 12 shipments of slurry were delivered. The new equipment engineered for the coal-water slurry system consisted of the following: combustion air and slurry heaters; cyclone; baghouse; fly ash reinjection system; new control system; air compressor; CWS/gas burner and gas valve train; and storage tank and slurry handling system.

  16. Pool boiling heat transfer enhancement over cylindrical tubes with water at atmospheric pressure, Part I: Experimental results

    E-Print Network [OSTI]

    Kandlikar, Satish

    tubes are generated by performing further pro- cesses on the finned tubes. They tested these surfaces and was fairly similar for all tubes. Huebner and Kuenstler [4] tested similar tubes with n-hexane and propane

  17. Direct observation of the topological charge of a terahertz vortex beam generated by a Tsurupica spiral phase plate

    SciTech Connect (OSTI)

    Miyamoto, K., E-mail: k-miyamoto@faculty.chiba-u.jp [Graduate School of Advanced Integration Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); Suizu, K.; Akiba, T. [Department of Electrical, Electronics and Computer Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016 (Japan); Omatsu, T. [Graduate School of Advanced Integration Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); CREST Japan Science and Technology Agency, Sanbancho, Chiyoda-ku, Tokyo 102-0075 (Japan)

    2014-06-30T23:59:59.000Z

    A terahertz (THz) spiral phase plate with high transmission (>90% after Fresnel correction) and low dispersion has been developed based on the Tsurupica olefin polymer. Direct observations of the topological charge (both magnitude and sign) of a THz vortex beam are performed by using a THz camera with tilted lens focusing and radial defect introduction. The vortex outputs with a topological charge of ±1 (or ±2) are obtained at a frequency of 2 (or 4) THz.

  18. automatic tube current: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    G. S. Bali; K. Schilling 1997-09-25 100 Observation of flux tube crossings in the solar wind CERN Preprints Summary: Current sheets are ubiquitous in the solar wind.They are a...

  19. Pressure tube testing test plan document production assurance program

    SciTech Connect (OSTI)

    Zaloudek, F.R. [Pacific Northwest Lab., Richland, WA (United States); Ruff, E.S. [UNC Nuclear Industries, Richland, WA (United States)

    1986-04-01T23:59:59.000Z

    UNC Nuclear Industries (UNC) has initiated a plan for the manufacture of zirconium alloy pressure tubes required for the future operation of N-Reactor. As part of this plan, UNC is establishing a program to qualify and develop a manufacturing process capable of fabricating these pressure tubes to the requirements of UNC specification HWS 6502, REV 4, Amendment 1. The objective of the task described in this test plan is to support the UNC program by performing physical/chemical testing on prototype tubes sections produced or procured during FY-1986, 1987 and 1988 and to test samples from production runs after 1988 as may be required. The types of tests included in this pressure tube testing task will be as follows: (1) Tensile tests; (2) Burst testing; (3) Tests to evaluate fracture properties; (4) Corrosion tests; (5) Spectrographic analysis of chemical composition; (6) Metallographic evaluation of grain size and oxide layer thickness.

  20. Design and Test of Tube & Shell Heat Exchangers for Potential

    E-Print Network [OSTI]

    Design and Test of Tube & Shell Heat Exchangers for Potential OTEC Application Jeong-Tae Kwon1 University, South Korea 2Department of Mechanical Engineering, Sunmoon University, South Korea 3Offshore CCS

  1. Midcontinent well operators learn advantages of coiled-tubing techniques

    SciTech Connect (OSTI)

    Lyle, D.

    1995-07-01T23:59:59.000Z

    From well cleanup to velocity strings to squeeze jobs, more Midcontinent operators are adding coiled-tubing methods to their oilfield techniques. The advantages of these techniques are discussed.

  2. Pressure drop with surface boiling in small-diameter tubes

    E-Print Network [OSTI]

    Dr?mer, Thomas

    1964-01-01T23:59:59.000Z

    Pressure drop for water flowing in small-diameter tubes under isothermal, nonboiling, and surface-boiling conditions was investigated. Experimental results for local pressure gradient and heattransfer coefficients are ...

  3. Defect specific maintenance of SG tubes -- How safe is it?

    SciTech Connect (OSTI)

    Cizelj, L.; Mavko, B.; Dvorsek, T. [Jozef Stefan Institute, Ljubljana (Slovenia)

    1997-02-01T23:59:59.000Z

    The efficiency of the defect specific plugging criterion for outside diameter stress corrosion cracking at tube support plates is assessed. The efficiency is defined by three parameters: (1) number of plugged tubes, (2) probability of steam generator tube rupture and (3) predicted accidental leak rate through the defects. A probabilistic model is proposed to quantify the probability of tube rupture, while procedures available in literature were used to define the accidental leak rates. The defect specific plugging criterion was then compared to the performance of traditional (45%) plugging criterion using realistic data from Krsko nuclear power plant. Advantages of the defect specific approach over the traditional one are clearly shown. Some hints on the optimization of safe life of steam generator are also given.

  4. TiN Coatings on Fuel Cladding Tube 

    E-Print Network [OSTI]

    Yu, Zhichao 1987-

    2012-05-04T23:59:59.000Z

    demonstrate this new design and deposite TiN on the tubes. A systematic physical property study including surface characterization (SEM), mechanical testing (hardness and scratch test), thermal cycle test and thermal conductivity measurements, was conducted...

  5. Design and fabrication of pressure-compensating compliant tubes

    E-Print Network [OSTI]

    Martin, Ian (Ian P.)

    2014-01-01T23:59:59.000Z

    Different fabrication methods are evaluated for producing pressure-compensating tubes for use in low-pressure drip irrigation systems. Such devices would allow drip irrigation systems to operate at driving pressures much ...

  6. Flow of Navier-Stokes Fluids in Cylindrical Elastic Tubes

    E-Print Network [OSTI]

    Sochi, Taha

    2013-01-01T23:59:59.000Z

    Analytical expressions correlating the volumetric flow rate to the inlet and outlet pressures are derived for the time-independent flow of Newtonian fluids in cylindrically-shaped elastic tubes using a one-dimensional Navier-Stokes flow model with two pressure-area constitutive relations. These expressions for elastic tubes are the equivalent of Poiseuille and Poiseuille-type expressions for rigid tubes which were previously derived for the flow of Newtonian and non-Newtonian fluids under various flow conditions. Formulae and procedures for identifying the pressure field and tube geometric profile are also presented. The results are validated by a finite element method implementation. Sensible trends in the analytical and numerical results are observed and documented.

  7. alloy clad tubes: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the reversal requires a certain relative velocity difference between plasma inside the flux tube and the environment, the ins... Holzwarth, Volkmar 2008-01-01 99 Liquid-core...

  8. Continuous Flow Coupling and Decarboxylation Reactions Promoted by Copper Tubing

    E-Print Network [OSTI]

    Zhang, Yun

    A convenient and efficient flow method for Ullmann condensations, Sonogashira couplings, and decarboxylation reactions using a commercially available copper tube flow reactor (CTFR) is described. The heated CTFR effects ...

  9. ab electronic tubes: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    advanced pressure-tube (PT) reactor being developed by Atomic Energy of Canada Limited (AECL). As in conventional CANDU reactors, the PTs are horizontal. Each PT is surrounded by a...

  10. aspiration neural tube: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    advanced pressure-tube (PT) reactor being developed by Atomic Energy of Canada Limited (AECL). As in conventional CANDU reactors, the PTs are horizontal. Each PT is surrounded by a...

  11. aluminium alloy tubes: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    advanced pressure-tube (PT) reactor being developed by Atomic Energy of Canada Limited (AECL). As in conventional CANDU reactors, the PTs are horizontal. Each PT is surrounded by a...

  12. alloy tubes application: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    advanced pressure-tube (PT) reactor being developed by Atomic Energy of Canada Limited (AECL). As in conventional CANDU reactors, the PTs are horizontal. Each PT is surrounded by a...

  13. advanced ceramic tube: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    advanced pressure-tube (PT) reactor being developed by Atomic Energy of Canada Limited (AECL). As in conventional CANDU reactors, the PTs are horizontal. Each PT is surrounded by a...

  14. Refrigerant forced-convection condensation inside horizontal tubes

    E-Print Network [OSTI]

    Bae, Soonhoon

    1970-01-01T23:59:59.000Z

    High vapor velocity condensation inside a tube was studied theoretically. The heat transfer coefficients were calculated by the momentum and heat transfer analogy. The Von Karman universal velocity distribution was applied ...

  15. Refrigerant forced-convection condensation inside horizontal tubes

    E-Print Network [OSTI]

    Bae, Soonhoon

    1969-01-01T23:59:59.000Z

    High vapor velocity condensation inside a tube was studied theoretically. The heat transfer coefficients were calculated by the momentum and heat transfer analogy. The Von Karman universal velocity distribution was applied ...

  16. assessing tube wall: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    tube drawing is a metal Paris-Sud XI, Universit de 35 LIFE CYCLE ASSESSMENT OF A HEMP CONCRETE WALL: IMPACT OF THICKNESS AND COATING. Physics Websites Summary: to reduce...

  17. X-ray tube with magnetic electron steering

    DOE Patents [OSTI]

    Reed, Kim W. (Albuquerque, NM); Turman, Bobby N. (Albuquerque, NM); Kaye, Ronald J. (Albuquerque, NM); Schneider, Larry X. (Albuquerque, NM)

    2000-01-01T23:59:59.000Z

    An X-ray tube uses a magnetic field to steer electrons. The magnetic field urges electrons toward the anode, increasing the proportion of electrons emitted from the cathode that reach desired portions of the anode and consequently contribute to X-ray production. The magnetic field also urges electrons reflected from the anode back to the anode, further increasing the efficiency of the tube.

  18. Methanation in catalyst-sprayed tube wall reactors: a review

    SciTech Connect (OSTI)

    Pennline, H. W.; Schehl, R. R.; Haynes, W. P.; Forney, A. J.

    1980-09-01T23:59:59.000Z

    The design and operation of catalyst-sprayed tube wall reactors for methanation are discussed. Reactor tubes were either coated on the inner surface or on the outer surface with a Raney nickel catalyst. A liquid coolant, which was opposite the catalyst-reactant gas-side, removed the heat of methanation. Catalyst performance, reactor operating conditions, spent catalyst analyses, and other results are presented for five PDU tests.

  19. Heat transfer in a two-pass internally ribbed turbine blade coolant channel with cylindrical vortex generators

    SciTech Connect (OSTI)

    Hibbs, R.; Chen, Y.; Nikitopoulos, D. [Louisiana State Univ., Baton Rouge, LA (United States)] [and others

    1995-10-01T23:59:59.000Z

    The effect of vortex generators on the mass (heat) transfer from the ribbed passage of a two pass turbine blade coolant channel is investigated with the intent of optimizing the vortex generator geometry so that significant enhancements in mass/heat transfer can be achieved. In the experimental configuration considered, ribs are mounted on two opposite walls; all four walls along each pass are active and have mass transfer from their surfaces but the ribs are non-participating. Mass transfer measurements, in the form of Sherwood number ratios, are made along the centerline and in selected inter-rib modules. Results are presented for Reynolds number in the range of 5,000 to 40,000, pitch to rib height ratios of 10.5 and 21, and vortex generator-rib spacing to rib height ratios of 0.55, and 1.5. Centerline and spanwise averaged Sherwood number ratios are presented along with contours of the Sherwood number ratios. Results indicate that the vortex generators induce substantial increases in the local mass transfer rates, particularly along the side walls, and modest increases in the average mass transfer rates. The vortex generators have the effect of making the inter-rib profiles along the ribbed walls more uniform. Along the side walls, horse-shoe vortices that characterize the vortex generator wake are associated with significant mass transfer enhancements. The wake effects and the levels of enhancement decrease somewhat with increasing Reynolds number and decreasing pitch.

  20. Heat transfer in a two-pass internally ribbed turbine blade coolant channel with cylindrical vortex generators

    SciTech Connect (OSTI)

    Hibbs, R.; Acharya, S.; Chen, Y. [Louisiana State Univ., Baton Rouge, LA (United States)] [and others

    1995-12-31T23:59:59.000Z

    The effect of vortex generators on the mass (heat) transfer from the ribbed passage of a two pass turbine blade coolant channel is investigated with the intent of optimizing the vortex generator geometry so that significant enhancements in mass/heat transfer can be achieved. In the experimental configuration considered, ribs are mounted on two opposite walls; all four walls along each pass are active and have mass transfer from their surfaces but the ribs are non-participating. Mass transfer measurements, in the form of Sherwood number ratios, are made along the centerline and in selected inter-rib modules. Results are presented for Reynolds number in the range of 5,000 to 40,000, pitch to rib height ratios of 10.5 and 21, and vortex generator-rib spacing to rib height ratios of 0.55, and 1.5. Centerline and spanwise averaged Sherwood number ratios are presented along with contours of the Sherwood number ratios. Results indicate that the vortex generators induce substantial increases in the local mass transfer rates, particularly along the side walls, and modest increases in the average mass transfer rates. The vortex generators have the effect of making the inter-rib profiles along the ribbed walls more uniform. Along the side walls, horse-shoe vortices that characterize the vortex generator wake are associated with significant mass transfer enhancements. The wake effects and the levels of enhancement decrease somewhat with increasing Reynolds number and decreasing pitch.

  1. Heat transfer in a two-pass internally ribbed turbine blade coolant channel with cylindrical vortex generators

    SciTech Connect (OSTI)

    Hibbs, R.G.; Acharya, S.; Chen, Y.; Nikitopoulos, D.E.; Myrum, T.A. [Louisiana State Univ., Baton Rouge, LA (United States). Mechanical Engineering Dept.

    1998-07-01T23:59:59.000Z

    The effect of vortex generators on the mass (heat) transfer from the ribbed passage of a two-pass turbine blade coolant channel is investigated with the intent of optimizing the vortex generator geometry so that significant enhancements in mass/heat transfer can be achieved. In the experimental configuration considered, ribs are mounted on two opposite walls; all four walls along each pass are active and have mass transfer from their surfaces but the ribs are nonparticipating. Mass transfer measurements, in the form of Sherwood number ratios, are made along the centerline and in selected interrib modules. Results are presented for Reynolds number in the range of 5000 to 40,000 pitch to rib height ratios of 10.5 and 21, and vortex generator-rib spacing to rib height ratios of 0.55 and 1.5. Centerline and spanwise-averaged Sherwood number ratios are presented along with contours of the Sherwood number ratios. Results indicate that the vortex generators lead to substantial increases in the local mass transfer rates, particularly along the side walls, and modest increases in the average mass transfer rates. The vortex generators have the effect of making the interrib profiles along the ribbed walls more uniform. Along the side walls, vortices that characterize the vortex generator wake are associated with significant mass transfer enhancements. The wake effects and the levels of enhancement decrease somewhat with increasing Reynolds number and decreasing pitch.

  2. General rotating quantum vortex filaments in the low-temperature Svistunov model of the local induction approximation

    SciTech Connect (OSTI)

    Van Gorder, Robert A., E-mail: rav@knights.ucf.edu [Department of Mathematics, University of Central Florida, Orlando, Florida 32816-1364 (United States)

    2014-06-15T23:59:59.000Z

    In his study of superfluid turbulence in the low-temperature limit, Svistunov [“Superfluid turbulence in the low-temperature limit,” Phys. Rev. B 52, 3647 (1995)] derived a Hamiltonian equation for the self-induced motion of a vortex filament. Under the local induction approximation (LIA), the Svistunov formulation is equivalent to a nonlinear dispersive partial differential equation. In this paper, we consider a family of rotating vortex filament solutions for the LIA reduction of the Svistunov formulation, which we refer to as the 2D LIA (since it permits a potential formulation in terms of two of the three Cartesian coordinates). This class of solutions holds the well-known Hasimoto-type planar vortex filament [H. Hasimoto, “Motion of a vortex filament and its relation to elastica,” J. Phys. Soc. Jpn. 31, 293 (1971)] as one reduction and helical solutions as another. More generally, we obtain solutions which are periodic in the space variable. A systematic analytical study of the behavior of such solutions is carried out. In the case where vortex filaments have small deviations from the axis of rotation, closed analytical forms of the filament solutions are given. A variety of numerical simulations are provided to demonstrate the wide range of rotating filament behaviors possible. Doing so, we are able to determine a number of vortex filament structures not previously studied. We find that the solution structure progresses from planar to helical, and then to more intricate and complex filament structures, possibly indicating the onset of superfluid turbulence.

  3. Methods for batch fabrication of cold cathode vacuum switch tubes

    DOE Patents [OSTI]

    Walker, Charles A. (Albuquerque, NM); Trowbridge, Frank R. (Albuquerque, NM)

    2011-05-10T23:59:59.000Z

    Methods are disclosed for batch fabrication of vacuum switch tubes that reduce manufacturing costs and improve tube to tube uniformity. The disclosed methods comprise creating a stacked assembly of layers containing a plurality of adjacently spaced switch tube sub-assemblies aligned and registered through common layers. The layers include trigger electrode layer, cathode layer including a metallic support/contact with graphite cathode inserts, trigger probe sub-assembly layer, ceramic (e.g. tube body) insulator layer, and metallic anode sub-assembly layer. Braze alloy layers are incorporated into the stacked assembly of layers, and can include active metal braze alloys or direct braze alloys, to eliminate costs associated with traditional metallization of the ceramic insulator layers. The entire stacked assembly is then heated to braze/join/bond the stack-up into a cohesive body, after which individual switch tubes are singulated by methods such as sawing. The inventive methods provide for simultaneously fabricating a plurality of devices as opposed to traditional methods that rely on skilled craftsman to essentially hand build individual devices.

  4. Recomplete deep hot wells successfully with coiled tubing

    SciTech Connect (OSTI)

    Garner, T.; Fleckenstein, W. [Bechtel Petroleum Operations, Tupman, CA (United States); Shelley, B. [Halliburton Energy Services, Bakersfield, CA (United States)

    1995-06-01T23:59:59.000Z

    A squeeze reperforation procedure in the Elk Hills, California field using coiled tubing included contaminating excess cement and jetting it from the well bore to eliminate the need to drill out cement before shooting new perforations. The 324-7R well was producing 260 b/d of oil through 2 7/8-in. production tubing, with a 20,000-scf/bbl gas-oil ratio (GOR). Bottomhole static temperature was 250 F. After pumping a cement squeeze to 9,000 ft trough 1{1/2}-in. coiled tubing (CT) run inside the production tubing, oil production increased to 550 b/d of oil, and the GOR decreased to 5,000 scf/bbl when new perforations were shot. Cement was pumped 9,000 ft through the CT and circulated back through the production tubing/CT annulus. Operation cost was estimated at 20% less than for a comparable job performance with conventional tubing. Cost of the CT squeeze was recovered by 58 days incremental production.

  5. Colour flux-tubes in static Pentaquark systems

    E-Print Network [OSTI]

    Pedro Bicudo; Nuno Cardoso; Marco Cardoso

    2011-11-01T23:59:59.000Z

    The colour fields created by the static tetraquark and pentaquark systems are computed in quenched SU(3) lattice QCD, with gauge invariant lattice operators, in a 24^3 x 48 lattice at beta=6.2 . We generate our quenched configurations with GPUs, and detail the respective benchmanrks in different SU(N) groups. While at smaller distances the coulomb potential is expected to dominate, at larger distances it is expected that fundamental flux tubes, similar to the flux-tube between a quark and an antiquark, emerge and confine the quarks. In order to minimize the potential the fundamental flux tubes should connect at 120o angles. We compute the square of the colour fields utilizing plaquettes, and locate the static sources with generalized Wilson loops and with APE smearing. The tetraquark system is well described by a double-Y-shaped flux-tube, with two Steiner points, but when quark-antiquark pairs are close enough the two junctions collapse and we have an X-shaped flux-tube, with one Steiner point. The pentaquark system is well described by a three-Y-shaped flux-tube where the three flux the junctions are Steiner points.

  6. MHK Technologies/SeaUrchin Vortex Reaction Turbine | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOfRose Bend < MHK ProjectsFlagshipNARECRhoInformation SeaUrchin

  7. Large amplitude spin torque vortex oscillations at zero external field using a perpendicular spin polarizer

    SciTech Connect (OSTI)

    Dussaux, A.; Rache Salles, B.; Jenkins, A. S.; Bortolotti, P.; Grollier, J.; Cros, V.; Fert, A. [Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France); Grimaldi, E., E-mail: eva.grimaldi@thalesgroup.com [Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France); CNES, 1 Avenue Edouard Belin, 31400 Toulouse (France); Khvalkovskiy, A. V. [Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France); A.M. Prokhorov General Physics Institute of RAS, Vavilova Str. 38, 119991 Moscow (Russian Federation); Kubota, H.; Fukushima, A.; Yakushiji, K.; Yuasa, S. [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan)

    2014-07-14T23:59:59.000Z

    We investigate the microwave response of a spin transfer vortex based oscillator in a magnetic tunnel junction with an in-plane reference layer combined with a spin valve with an out-of-plane magnetization spin polarizing layer. The main advantage of this perpendicular spin polarizer is to induce a large spin transfer force even at zero magnetic field, thus leading to a record emitted power (up to 0.6??W) associated to a very narrow spectral linewidth of a few hundreds of kHz. The characteristics of this hybrid vortex based spin transfer nano-oscillator obtained at zero field and room temperature are of great importance for applications based on rf spintronic devices as integrated and tunable microwave source and/or microwave detector.

  8. Von K\\'arm\\'an Vortex Street within an Impacting Drop

    E-Print Network [OSTI]

    Thoraval, Marie-Jean; Etoh, Takeharu Goji; Popinet, Stephane; Ray, Pascal; Josserand, Christophe; Zaleski, Stephane; Thoroddsen, Sigurdur

    2012-01-01T23:59:59.000Z

    The splashing of a drop impacting onto a liquid pool produces a range of different sized micro-droplets. At high impact velocities, the most significant source of these droplets is a thin liquid jet emerging at the start of the impact from the neck that connects the drop to the pool. We use ultra-high-speed video imaging in combination with high-resolution numerical simulations to show how the ejecta gives way to irregular splashing. At higher Reynolds number, its base becomes unstable, shedding vortex rings into the liquid from the free surface in an axisymmetric von K\\'arm\\'an vortex street, thus breaking the ejecta sheet as it forms.

  9. Analytical Tendex and Vortex Fields for Perturbative Black Hole Initial Data

    E-Print Network [OSTI]

    Kenneth A. Dennison; Thomas W. Baumgarte

    2012-07-10T23:59:59.000Z

    Tendex and vortex fields, defined by the eigenvectors and eigenvalues of the electric and magnetic parts of the Weyl curvature tensor, form the basis of a recently developed approach to visualizing spacetime curvature. In particular, this method has been proposed as a tool for interpreting results from numerical binary black hole simulations, providing a deeper insight into the physical processes governing the merger of black holes and the emission of gravitational radiation. Here we apply this approach to approximate but analytical initial data for both single boosted and binary black holes. These perturbative data become exact in the limit of small boost or large binary separation. We hope that these calculations will provide additional insight into the properties of tendex and vortex fields, and will form a useful test for future numerical calculations.

  10. Tripolar vortex formation in dense quantum plasma with ion-temperature-gradients

    SciTech Connect (OSTI)

    Qamar, Anisa; Ata-ur-Rahman [Institute of Physics and Electronics, University of Peshawar, Khyber Pakhtoon Khwa 25000 (Pakistan); National Center for Physics Shahdrah Valley Road, Islamabad 44000 (Pakistan); Mirza, Arshad M. [Theoretical Plasma Physics Group, Physics Department, Quaid-i-Azam University, Islamabad 45320 (Pakistan)

    2012-05-15T23:59:59.000Z

    We have derived system of nonlinear equations governing the dynamics of low-frequency electrostatic toroidal ion-temperature-gradient mode for dense quantum magnetoplasma. For some specific profiles of the equilibrium density, temperature, and ion velocity gradients, the nonlinear equations admit a stationary solution in the form of a tripolar vortex. These results are relevant to understand nonlinear structure formation in dense quantum plasmas in the presence of equilibrium ion-temperature and density gradients.

  11. Hierarchical Colloidal Vortex Rings in a Constant Electric Field Yilong Han and David G. Grier

    E-Print Network [OSTI]

    Grier, David

    often, the dense ring of 30 25 20 15 10 5 0 15 (b) (c) (d) (e) packed close- core vortex ring (d) (e) (b) (c) (a) (f) corona t [sec] Rg (t) [µm] +V h H 20 µm glass slide cluster electrode R g 20 µm FIG. 1 is surrounded by a di#11;use circulating corona that extends outward for tens of micrometers. Although

  12. Under consideration for publication in J. Fluid Mech. 1 Three-dimensional vortex dynamics in

    E-Print Network [OSTI]

    Pawlak, Geno

    , the boundary layer can become centrifugally unstable (Honji 1981), leading to well-developed G¨ortler vortices dissipation and boundary layer dynamics. It is widely accepted that vortex shedding is a dominant pr in oscillatory flow separation M I G U E L C A N A L S AND G E N O P A W L A K Department of Ocean and Resources

  13. Vortex free energy and deconfinement in center-blind discretizations of Yang-Mills theories

    E-Print Network [OSTI]

    Burgio, G; Kerler, W; Müller-Preussker, M

    2006-01-01T23:59:59.000Z

    Maximal 't Hooft loops are studied in SO(3) lattice gauge theory at finite temperature T. Tunneling barriers among twist sectors causing loss of ergodicity for local update algorithms are overcome through parallel tempering, enabling us to measure the vortex free energy F and to identify a deconfinement transition at some $\\beta_A^{crit}$. The behavior of F below $\\beta_A^{crit}$ shows however striking differences with what is expected from discretizations in the fundamental representation.

  14. Nanoscale strain-induced pair suppression as a vortex-pinning mechanism in high- temperature superconductors

    SciTech Connect (OSTI)

    Llordes, Anna [ICMAB, Barcelona, Spain; Palau, A. [ICMAB, Barcelona, Spain; Gazquez, J. [Oak Ridge National Laboratory (ORNL); Coll, M. [ICMAB, Barcelona, Spain; Vlad, R. [ICMAB, Barcelona, Spain; Pomar, A. [ICMAB, Barcelona, Spain; Arbiol, Jordi [ICMAB, Barcelona, Spain; Guzman, Roger [ICMAB, Barcelona, Spain; Ye, S. [ICMAB, Barcelona, Spain; Rouco, V [ICMAB, Barcelona, Spain; Sandiumenge, Felip [ICMAB, Barcelona, Spain; Ricart, Susagna [ICMAB, Barcelona, Spain; Puig, Teresa [ICMAB, Barcelona, Spain; Varela del Arco, Maria [ORNL; Chataigner, D. [CRISMAT, Caen, France; Vanacken, J. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Gutierrez, J. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Moschalkov, V. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Deutscher, G. [Tel Aviv University; Magen Dominguez, Cesar [ORNL; Obradors, Xavier [ICMAB, Barcelona, Spain

    2012-01-01T23:59:59.000Z

    Boosting large-scale superconductor applications require nanostructured conductors with artificial pinning centres immobilizing quantized vortices at high temperature and magnetic fields. Here we demonstrate a highly effective mechanism of artificial pinning centers in solution-derived high-temperature superconductor nanocomposites through generation of nanostrained regions where Cooper pair formation is suppressed. The nanostrained regions identified from transmission electron microscopy devise a very high concentration of partial dislocations associated with intergrowths generated between the randomly oriented nanodots and the epitaxial YBa{sub 2}Cu{sub 3}O{sub 7} matrix. Consequently, an outstanding vortex-pinning enhancement correlated to the nanostrain is demonstrated for four types of randomly oriented nanodot, and a unique evolution towards an isotropic vortex-pinning behaviour, even in the effective anisotropy, is achieved as the nanostrain turns isotropic. We suggest a new vortex-pinning mechanism based on the bond-contraction pairing model, where pair formation is quenched under tensile strain, forming new and effective core-pinning regions.

  15. Cloudnet Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Hogan, Robin

    Cloudnet is a research project supported by the European Commission. This project aims to use data obtained quasi-continuously for the development and implementation of cloud remote sensing synergy algorithms. The use of active instruments (lidar and radar) results in detailed vertical profiles of important cloud parameters which cannot be derived from current satellite sensing techniques. A network of three already existing cloud remote sensing stations (CRS-stations) will be operated for a two year period, activities will be co-ordinated, data formats harmonised and analysis of the data performed to evaluate the representation of clouds in four major european weather forecast models.

  16. Observations of erosion of in-bed tubes in the Great Lake AFBC

    SciTech Connect (OSTI)

    Kantesaria, P.P.; Jukkola, G.D.

    1983-10-01T23:59:59.000Z

    Erosion measurements have been made on evaporator tubes, superheater tubes and front wall tubes in the atmospheric, fluidised-bed combustor, demonstration plant at Great Lakes Naval Base, Chicago. A brief indication of the results obtained is given. High erosion rates on vertical tube surfaces were attributed to the tendency of bubbles rising through the bed to follow preferred paths along the vertical surfaces.

  17. Apparatus and method for controlling heat transfer between a fluidized bed and tubes immersed therein

    DOE Patents [OSTI]

    Hodges, James L. (3 Hilltop Ave., Vernon, CT 06066); Cerkanowicz, Anthony E. (8 Fieldstone Dr., Livingston, NJ 07039)

    1983-01-01T23:59:59.000Z

    In a fluidized bed of solid particles having one or more heat exchange tubes immersed therein, the rate of heat transfer between the fluidized particles and a fluid flowing through the immersed heat exchange tubes is controlled by rotating an arcuate shield apparatus about each tube to selectively expose various portions of the tube to the fluidized particles.

  18. Apparatus and method for controlling heat transfer between a fluidized bed and tubes immersed therein

    DOE Patents [OSTI]

    Hodges, James L. (3 Hilltop Ave., Vernon, CT 06066); Cerkanowicz, Anthony E. (8 Fieldstone Dr., Livingston, NJ 07039)

    1982-01-01T23:59:59.000Z

    In a fluidized bed of solid particles having one or more heat exchange tubes immersed therein, the rate of heat transfer between the fluidized particles and a fluid flowing through the immersed heat exchange tubes is controlled by rotating an arcuate shield apparatus about each tube to selectively expose various portions of the tube to the fluidized particles.

  19. Method and apparatus for selective retraction of a tubing carried perforating gun

    SciTech Connect (OSTI)

    Rubbo, R.P.

    1990-12-25T23:59:59.000Z

    This patent describes apparatus for telescopically retracting a subterranean well tubing carried perforating gun.

  20. Facilitation of macroalgae by the sedimentary tube forming polychaete Diopatra cuprea

    E-Print Network [OSTI]

    McGlathery, Karen

    ). Seventy percent of the number of mudflat macroalgae were found incorporated into protruding D. cuprea tube

  1. Residual stress in laser welded dissimilar steel tube-to-tube joints

    SciTech Connect (OSTI)

    Sun, Zheng (Technical Research Centre of Finland, Espoo (Finland). Lab. of Production Engineering)

    1993-09-01T23:59:59.000Z

    Austenitic-ferritic dissimilar steel joints are widely used in power generation systems. Their utilization has proved to be efficient in terms of satisfactory properties and the economics. These types of joints have usually been produced using conventional welding processes, such as tungsten inert gas (TIG) welding. With the rapid development of high power lasers, laser welding has received considerable attention. Laser welding offers many advantages over conventional welding processes, e.g. low heat input, small heat-affected zone (HAZ), small distortion, and welding in an exact and reproducible manner. Residual stress distribution in laser welds may also differ from those made by conventional welding processes due to its special features. Residual stress, particularly tensile residual stress in the weld, can be very important factor in controlling the quality and service life of the welded structure. The formation of tensile residual stress in the weld may result in the initiation of fatigue cracking, stress corrosion cracking or other types of fractures. It is useful, therefore, to understand the distribution of residual stress in austenitic-ferritic laser welds, and thus evaluate the quality of the joints. Although residual stress distribution in the welded joints has been extensively investigated, little data are available for the residual stress distribution in laser welds. The aim of the work was to examine residual stress distribution along laser welds of dissimilar steel tube-to-tube joints, which were made by both autogeneous welding and welding with filler wire. The results were also compared with the joints made by plasma arc and TIG welding.

  2. Los Alamos National Laboratory W76 Pit Tube Lifetime Study

    SciTech Connect (OSTI)

    Abeln, Terri G. [Los Alamos National Laboratory

    2012-04-25T23:59:59.000Z

    A metallurgical study was requested as part of the Los Alamos National Laboratory (LANL) W76-1 life-extension program (LEP) involving a lifetime analysis of type 304 stainless steel pit tubes subject to repeat bending loads during assembly and disassembly operations at BWXT/Pantex. This initial test phase was completed during the calendar years of 2004-2006 and the report not issued until additional recommended tests could be performed. These tests have not been funded to this date and therefore this report is considered final. Tubes were reportedly fabricated according to Rocky Flats specification P14548 - Seamless Type 304 VIM/VAR Stainless Steel Tubing. Tube diameter was specified as 0.125 inches and wall thickness as 0.028 inches. A heat treat condition is not specified and the hardness range specification can be characteristic of both 1/8 and 1/4 hard conditions. Properties of all tubes tested were within specification. Metallographic analysis could not conclusively determine a specified limit to number of bends allowable. A statistical analysis suggests a range of 5-7 bends with a 99.95% confidence limit. See the 'Statistical Analysis' section of this report. The initial phase of this study involved two separate sets of test specimens. The first group was part of an investigation originating in the ESA-GTS [now Gas Transfer Systems (W-7) Group]. After the bend cycle test parameters were chosen (all three required bends subjected to the same amount of bend cycles) and the tubes bent, the investigation was transferred to Terri Abeln (Metallurgical Science and Engineering) for analysis. Subsequently, another limited quantity of tubes became available for testing and were cycled with the same bending fixture, but with different test parameters determined by T. Abeln.

  3. Spent Nuclear Fuel project, project management plan

    SciTech Connect (OSTI)

    Fuquay, B.J.

    1995-10-25T23:59:59.000Z

    The Hanford Spent Nuclear Fuel Project has been established to safely store spent nuclear fuel at the Hanford Site. This Project Management Plan sets forth the management basis for the Spent Nuclear Fuel Project. The plan applies to all fabrication and construction projects, operation of the Spent Nuclear Fuel Project facilities, and necessary engineering and management functions within the scope of the project

  4. ERIS Project 

    E-Print Network [OSTI]

    Hunter, Philip

    repositories. If these (generally) smaller institutions wished to continue to have access to these hosted repository spaces after the end of the project, it was proposed that these repository-lite services would be administered by the SDLC (the Scottish Digital...

  5. PROJECT SELECTIONS FOR DOE PHASE III XLERATOR SMALL BUSINESS PROGRAM |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking ofOilNEWResponse(Expired) | DepartmentINLDepartment of Energy PROJECT

  6. Project Financing: From Identification to Implementation | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreakingMay 2015 < prev next >Presentations Program4DepartmentProject

  7. Funding & Financing for Energy Projects | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdf Flash2006-52.pdf0.pdfDepartment ofEnergy 3 FuelModel |MinimalProjects Funding

  8. Applying a tapered electrode on a porous ceramic support tube by masking a band inside the tube and drawing in electrode material from the outside of the tube by suction

    DOE Patents [OSTI]

    Vasilow, T.R.; Zymboly, G.E.

    1991-12-17T23:59:59.000Z

    An electrode is deposited on a support by providing a porous ceramic support tube having an open end and closed end; masking at least one circumferential interior band inside the tube; evacuating air from the tube by an evacuation system, to provide a permeability gradient between the masked part and unmasked part of the tube; applying a liquid dispersion of solid electrode particles to the outside surface of the support tube, where liquid flows through the wall, forming a uniform coating over the unmasked support part and a tapered coating over the masked part. 2 figures.

  9. Reliability of steam generator tubes with axial cracks

    SciTech Connect (OSTI)

    Cizelj, L.; Mavko, B. [Jozef Stefan Inst., Ljubljana (Slovenia). Reactor Engineering Div.; Vencelj, P. [Univ. of Ljubljana (Slovenia). Faculty of Mathematics and Physics

    1996-11-01T23:59:59.000Z

    An approach for estimating the failure probability of tubes containing through-wall axial cracks has already been proposed by the authors. It is based on probabilistic fracture mechanics and accounts for scatter in tube geometry and material properties, scatter in residual and operational stresses responsible for crack propagation, and characteristics of nondestructive examination and plugging procedures (e.g., detection probability, sizing accuracy, human errors). Results of preliminary tests demonstrated wide applicability of this approach and triggered some improvements. The additions to the model are extensively discussed in this paper. Capabilities are demonstrated by results of analysis of steam generator no. 1 in Slovenian nuclear power plant located in Krsko after the 1992 inspection and plugging campaign. First, the number of cracked tubes and the crack length distribution were estimated using data obtained by the 100% motorized pancake coil inspection. The inspection and plugging activities were simulated in the second step to estimate the efficiency of maintenance in terms of single and multiple-tube rupture probabilities. They were calculated as a function of maximum allowable crack length. The importance of human errors and some limitations of present nondestructive examination techniques were identified. The traditional wall thickness and crack-length-based plugging criteria are compared. The crack-length-based criterion is shown to be more efficient and more safe, especially because of strong suppression effect on probability of multiple-tube rupture. The results are considered to be important for safety and maintenance of existing plants and for further research.

  10. The Dynamics of Flux Tubes in a High Beta Plasma

    E-Print Network [OSTI]

    E. T. Vishniac

    1994-07-21T23:59:59.000Z

    We suggest a new model for the structure of a magnetic field embedded high $\\beta$ turbulent plasma, based on the popular notion that the magnetic field will tend to separate into individual flux tubes. We point out that interactions between the flux tubes will be dominated by coherent effects stemming from the turbulent wakes created as the fluid streams by the flux tubes. Balancing the attraction caused by shielding effects with turbulent diffusion we find that flux tubes have typical radii comparable to the local Mach number squared times the large scale eddy length, are arranged in a one dimensional fractal pattern, have a radius of curvature comparable to the largest scale eddies in the turbulence, and have an internal magnetic pressure comparable to the ambient pressure. When the average magnetic energy density is much less than the turbulent energy density the radius, internal magnetic field and curvature scale of the flux tubes will be smaller than these estimates. Realistic resistivity does not alter the macroscopic properties of the fluid or the large scale magnetic field. In either case we show that the Sweet-Parker reconnection rate is much faster than an eddy turnover time. Realistic stellar plasmas are expected to either be in the ideal limit (e.g. the solar photosphere) or the resistive limit (most of the solar convection zone). All current numerical simulations of three dimensional MHD turbulence are in the viscous regime and are inapplicable to stars or accretion disks.

  11. An improved model for flashing flow in short tubes

    SciTech Connect (OSTI)

    Tilton, J.D.; Kornhauser, A.A. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Dept. of Mechanical Engineering

    1996-12-31T23:59:59.000Z

    Short tube restrictors are commonly used as expansion devices in refrigeration and heat pumping systems. Flashing flow through short tubes is choked, i.e. independent of downstream conditions. Flow rate is typically predicted by empirically correcting the flow rate of compressed liquid from upstream pressure to saturation pressure at upstream temperature. The empirical correction factors depend on pressure and temperature, on short tube geometry, and on the refrigerant used. This work extends and improves a model of short tube flow based on the physics of the observed flow phenomena. Short tube flow is believed to consist of a core of superheated liquid surrounded by an annulus of vapor. Evaporation is driven by heat transfer form the core to tine interface, and the flow is choked by the evaporated vapor. Flow rate is modeled by calculating the heat transfer rate, the evaporation rate, and the choking effect of the vapor. The model attempts to improve on previous work by improving the accuracy with which thermodynamic properties are approximated, by improving the heat transfer model, and by including the effects of frictional heating of the liquid. In comparisons with experimental data it is found that the improved thermodynamic modeling increases accuracy, but the change to the heat transfer model reduces accuracy. For the data examined the effects of the frictional heating are small. The heat transfer model is based on an existing analytic solution with a mixing-length turbulence model. It appears that this model must be further improved, perhaps through empirical modification.

  12. Project Fact Sheet Project Brief

    E-Print Network [OSTI]

    Name: Centre for Assisted Robotic Surgery Number: BESS1002b Project Champion: Professor Guang-Zong Yang of the refurbishment is to renew and expand the laboratory space for Robotic Assisted Surgery at the South Kensington Campus as par to the Hamlyn Centre for Robotic Surgery. The overall programme incorpo- rates both core

  13. Heat exchanger performance calculations for enhanced-tube condenser applications

    SciTech Connect (OSTI)

    Rabas, T.J.

    1992-01-01T23:59:59.000Z

    The lack of a prediction method is sometimes used for the rejection of enhanced tubes for some condenser applications even though there is ample data from single-tube condensing experiments. Three methods are discussed that can be used to rate and/or size these multitube units based on the single-tube experimental results. The Kern vertical-number correction appears to be quite adequate for most operating conditions, the exceptions being large sizes and/or deep vacuum operation. The bundle-factor method is preferred for these applications; however, field test results are required to obtain this factor. If performance data are not available, pointwise or numerical methods are required but special care must be taken to insure that the adverse effects of noncondensable gas pockets and the saturation-temperature depression are properly addressed.

  14. Heat exchanger performance calculations for enhanced-tube condenser applications

    SciTech Connect (OSTI)

    Rabas, T.J.

    1992-07-01T23:59:59.000Z

    The lack of a prediction method is sometimes used for the rejection of enhanced tubes for some condenser applications even though there is ample data from single-tube condensing experiments. Three methods are discussed that can be used to rate and/or size these multitube units based on the single-tube experimental results. The Kern vertical-number correction appears to be quite adequate for most operating conditions, the exceptions being large sizes and/or deep vacuum operation. The bundle-factor method is preferred for these applications; however, field test results are required to obtain this factor. If performance data are not available, pointwise or numerical methods are required but special care must be taken to insure that the adverse effects of noncondensable gas pockets and the saturation-temperature depression are properly addressed.

  15. Friction Factor Measurements in an Equally Spaced Triangular Tube Array

    SciTech Connect (OSTI)

    Vassallo P, Symolon P

    2007-03-19T23:59:59.000Z

    Friction factor data for adiabatic cross-flow of water in a staggered tube array was obtained over a Reynolds number range (based on hydraulic diameter and gap velocity) of about 10,000 to 250,000. The tubes were 12.7mm (0.5 inch) outer diameter, in a uniformly spaced triangular arrangement with a pitch-to-diameter ratio of 1.5. The friction factor was compared to several literature correlations, and was found to be best matched by the Idelchik correlation. Other correlations were found to vary significantly from the test data. Based on the test data, a new correlation is proposed for this tube bundle geometry which covers the entire Reynolds number range tested.

  16. Thermal Behavior of Floor Tubes in a Kraft Recovery Boiler

    SciTech Connect (OSTI)

    Barker, R.E.; Choudhury, K.A.; Gorog, J.P.; Hall, L.M.; Keiser, J.R.; Sarma, G.B.

    1999-09-12T23:59:59.000Z

    The temperatures of floor tubes in a slope-floored black liquor recovery boiler were measured using an array of thermocouples located on the tube crowns. It was found that sudden, short duration temperature increases occurred with a frequency that increased with distance from the spout wall. To determine if the temperature pulses were associated with material falling from the convective section of the boiler, the pattern of sootblower operation was recorded and compared with the pattern of temperature pulses. During the period from September, 1998, through February, 1999, it was found that more than 2/3 of the temperature pulses occurred during the time when one of the fast eight sootblowers, which are directed at the back of the screen tubes and the leading edge of the first superheater bank, was operating.

  17. Interaction of a monopole vortex with an isolated topographic feature in a three-layer geophysical flow

    E-Print Network [OSTI]

    Evgeny A. Ryzhov; K. V. Koshel

    2012-09-27T23:59:59.000Z

    In the frame of a three-layer quasi-geostrophic analytical model of a $f$-plane geophysical flow, Lagrangian advection being induced by the interaction of a monopole vortex with an isolated topographic feature is addressed. Two different cases when the monopole locates either within the upper or the middle layer are of our interest. In the bottom layer, there is a delta function topographic feature, which generates a closed recirculation region in its vicinity due to the background flow. This recirculation region extends to the middle and upper layers, and it plays the role of a topographic vortex. The interaction between the monopole and the topographic vortex causes complex, including chaotic, advection of fluid particles. We show that the model's parameters, namely, the monopole and topographic vortices' strengths and initial positions, the layers' depths and densities are responsible for the diverse advection patterns. While the patterns are rather complicated, however, one can single out two major processes, which mostly govern fluid particle advection. The first one is the variation in time of the system's phase space structure, so that within the closed region of the topographic vortex, there appear periodically unclosed particle pathways by which the particles leave the topographic vortex. The second one is chaotic advection that arises from the nonstationarity of the monopole-topography interaction.

  18. Improving Efficiency of Tube Drawing Bench | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

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  19. Method for forming a layer of synthetic corrosion products on tubing surfaces

    DOE Patents [OSTI]

    Lane, Michael H. (Clifton Park, NY); Salamon, Eugene J. M. (Clifton Park, NY)

    1996-01-01T23:59:59.000Z

    A method is provided for forming a synthetic corrosion product layer on tube surfaces. The method utilizes two dissimilar materials with different coefficients of thermal expansion. An object tube and sacrificial tube are positioned one inside the other such that an annular region is created between the two tubes' surfaces. A slurry of synthetic corrosion products is injected into this annular region and the assembly is heat treated. This heat causes the tubes to expand, the inner tube with the higher coefficient of expansion expanding more than the outer tube, thereby creating internal pressures which consolidate the corrosion products and adhere the corrosion products to the tubing surfaces. The sacrificial tube may then be removed by conventional chemical etching or mechanical methods.

  20. Controlled propagation of locally excited vortex dynamics in linear nanomagnet arrays This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Otani, Yoshichika

    Controlled propagation of locally excited vortex dynamics in linear nanomagnet arrays This article. Here, we present a controlled propagation of locally excited magnetic vortex dynamics through a linear. Phys. D: Appl. Phys. 43 (2010) 335001 (7pp) doi:10.1088/0022-3727/43/33/335001 Controlled propagation