Sample records for type axial flow

  1. Title: Scalable Low-Head Axial-Type Venturi-Flow Energy Principal Investigator: Nadipuram Prasad

    E-Print Network [OSTI]

    Johnson, Eric E.

    a basis to design and develop a novel, scalable, low cost, easy to manufacture and assemble, modular and developed. Based upon the harvester specifications derived, NMSU will fabricate a 10kW hydropower harvester-of-river type water-flow mechanisms. Achieving this goal paves the way towards rapid commercialization

  2. Piezoelectric axial flow microvalve

    SciTech Connect (OSTI)

    Gemmen, Randall; Thornton, Jimmy; Vipperman, Jeffrey S.; Clark, William W.

    2007-01-09T23:59:59.000Z

    This invention is directed to a fuel cell operable with a quantity of fuel and a quantity of an oxidizer to produce electrical power, the fuel cell including a fuel cell body including a labyrinth system structured to permit the fuel and the oxidizer to flow therethrough; at least a first catalyst in fluid communication with the labyrinth; and at least a first microvalve operably disposed within at least a portion of the labyrinth. The microvalve utilizes a deflectable member operable upon the application of a voltage from a voltage source. The microvalve includes an elongated flow channel formed therein and extending substantially longitudinally between the first and second ends to permit substantially longitudinal flow of the fluid therethrough and between the first and second ends; and the deflectable member disposed on the valve body, the deflectable member including at least a first piezoelectric portion that is piezoelectrically operable to deflect the deflectable member between an open position and a closed position upon the application of a voltage, the deflectable member in the closed position being operable to resist the flow of the fluid through the flow channel.

  3. Flow Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY); LaBelle, James (Murrieta, CA)

    2000-02-22T23:59:59.000Z

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. An axially aligned outlet may also increase the flow efficiency. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane. A seal separator may increase the useful life of the seal between the fixed and rotatable portions.

  4. Study of casing treatment effects in axial flow compressors

    E-Print Network [OSTI]

    Schiller, Robert Neil

    1973-01-01T23:59:59.000Z

    to in- creased tip leakage between shroud and blade tip. Figure (I) shows a typical performance curve for an axial flow compressor. Note that as pressure ratio increases, the operating 'range between surge and stall is decreased, there by reducing... the surge to stall margin of the axial flow compressor. REFERENCES I 1 ~ 4 Koch, C. C. , "Experimental Evaluation of Outer Case Blowing or Bleeding of Single Stage Axial Flow Compressor". , Part IV. Rep. R 69AEG256, General Electric Co. , (NASA CR...

  5. An investigation of axial-flow compressor blade treatments

    E-Print Network [OSTI]

    Sangerhausen, Charles Roger

    1974-01-01T23:59:59.000Z

    of axial-flow compressor [5] . According to Schlicting [1], the basic methods of controlling the boundary layer on a body are (1) relative motion of the body surface w1th the flow, (2) acceleration of the boundary layer by blowing, (3) suction, (0) in...c methods. The literature survey revealed that three d1fferent techn1ques of boundary layer oontrol have been investigated for applicat1on to axial- flow compressor bladingi these are (1) the slotted blade, (2) the blade shape designed for a...

  6. Effect of circumferential groove casing treatment parameters on axial compressor flow range

    E-Print Network [OSTI]

    Hanley, Brian K. (Brian Kyle)

    2010-01-01T23:59:59.000Z

    The impact on compressor flow range of circumferential casing grooves of varying groove depth, groove axial location, and groove axial extent is assessed against that of a smooth casing wall using computational experiments. ...

  7. A simple criterion for three-dimensional flow separation in axial compressors

    E-Print Network [OSTI]

    Lei, Vai-Man

    2006-01-01T23:59:59.000Z

    Most modem blade designs in axial-flow compressors diffuse the flow efficiently over 20% to 80% of blade span and it is the endwall regions that set the limits in compressor performance. This thesis addresses the estimation, ...

  8. Secondary air interaction with main flow in axial turbines

    E-Print Network [OSTI]

    Zlatinov, Metodi B. (Metodi Blagoev)

    2011-01-01T23:59:59.000Z

    Secondary air, known as purge air, is injected through seals in the hub and shroud of axial turbines to prevent hot gas ingestion into the endwall cavities. An investigation into the interaction of purge ow with turbine ...

  9. axial flow pump: Topics by E-print Network

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

    and Information Sciences Websites Summary: of a configuration that includes an axial pump and a bundle of tubes that mimics the cool source of a heat exchangerEXPERIMENTAL AND...

  10. Performance characteristics of a low pressure cyclone for axial-flow fan exhausts

    E-Print Network [OSTI]

    Simpson, Shay Lynn

    1996-01-01T23:59:59.000Z

    on axial-flow fan exhausts to significantly reduce particulate emissions. Average emission concentrations, cut-point diameters, PMIO emission concentrations, and fractional efficiencies from this cyclone operating at different cyclone inlet velocities...

  11. Effect of flow oscillations on axial energy transport in a porous material

    SciTech Connect (OSTI)

    Siegel, R. (NASA Lewis Research Center, Cleveland, OH (USA))

    1987-02-01T23:59:59.000Z

    It has been shown analytically and experimentally that flow oscillations of a fluid within a channel can enhance the axial transfer of energy. The transport arises from an axial gradient in fluid temperature resulting from having reservoirs at different temperatures at either end of the channel. The present analysis develops relations for axial energy diffusion in a porous medium with oscillating flow. In some devices, such as the Sterling engine, there are regenerators with oscillating flow. Axial transport in the regenerator provides an energy loss; hence it is desirable to determine what factors can limit this diffusion. A regenerator in the form of a porous medium is difficult to model since the flow is continually disrupted by the irregularities of the porous structure. The formulation here will employ an internal heat transfer coefficient that couples the fluid and solid temperatures. The final result shows how the diffusion depends on the magnitude of the heat transfer coefficient and the maximum fluid displacement.

  12. EXPERIMENTAL AND NUMERICAL ANALYSIS OF THE FLOW INSIDE A CONFIGURATION INCLUDING AN AXIAL PUMP AND A TUBULAR

    E-Print Network [OSTI]

    Boyer, Edmond

    EXPERIMENTAL AND NUMERICAL ANALYSIS OF THE FLOW INSIDE A CONFIGURATION INCLUDING AN AXIAL PUMP-30723) In centrifugal and axial pumps, the flow is characterized by a turbulent and complex behavior and also of a configuration that includes an axial pump and a bundle of tubes that mimics the cool source of a heat exchanger

  13. Tip clearance flows in axial compressors: stall inception and stability enhancement

    E-Print Network [OSTI]

    Weichert, Stephanie April

    2012-02-07T23:59:59.000Z

    The flow in the rotor tip clearance gap in an axial compressor influences the loss levels and the stall onset point. The role of tip clearance flows in the stall inception process is still debated, though. The aim of this thesis is to improve...

  14. axial flow blood: Topics by E-print Network

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

    the case of an aneurism. Delestre, Olivier 2012-01-01 193 Blood-Flow Modelling Along and Trough a Braided Multi-Layer Metallic Stent CERN Preprints Summary: In this work we study...

  15. Role of tip clearance flow on axial compressor stability

    E-Print Network [OSTI]

    Vo, Huu Duc, 1971-

    2002-01-01T23:59:59.000Z

    An examination of the fluid dynamic phenomena that link tip clearance flow to the formation of short length-scale (spike) rotating stall disturbances has been carried out. It is found that the onset of growth in tip clearance ...

  16. Convective Heat Transfer and Reference Free-stream Temperature Determination near the Casing of an Axial Flow

    E-Print Network [OSTI]

    Camci, Cengiz

    of an Axial Flow Turbine B. Gumusel 2 and C. Camci 1 Turbomachinery Aero-Heat Transfer Laboratory Department on the casing of an axial flow turbine. The goal is to develop an accurate steady-state heat transfer method for the comparison of various casing surface and tip designs used for turbine performance improvements. The free

  17. The development of blade profiles for a supersonic axial flow compressor

    E-Print Network [OSTI]

    Bearden, John Lee

    1972-01-01T23:59:59.000Z

    . Therefore, the Mach number before the normal shock is reduced, thereby reducing the shock losses. The adiabatic efficiency obtained was fairly low (0. 67). The authors attributed this to the detached bow wave remaining at the rotor inlet... be used when ). (t/c) is small compared to unity (28) . The last condi- tion is satisfied as long as the bow or leading edge shock is attached. Applying linearized theory to the flow problem in axial com- pressor rotors and stators, equations can...

  18. Impact of unsteady flow processes on the performance of a high speed axial flow compressor

    E-Print Network [OSTI]

    Botros, Barbara Brenda

    2008-01-01T23:59:59.000Z

    This thesis examines the unsteady interactions between blade rows in a high Mach number, highly-loaded compressor stage. Two straight vane/rotor configurations with different axial spacing between vane and rotor are ...

  19. Impact of unsteady secondary air flow interaction with main flow on loss generation in axial turbines

    E-Print Network [OSTI]

    Clifton, David (David Madison)

    2014-01-01T23:59:59.000Z

    Secondary air, often called purge air, is injected through the endwall gap between stationary vanes and rotating rotors in axial turbines to prevent ingestion of the hot working gas into the endwall cavities. Three-dimensional ...

  20. Analysis Of Residence Time Distribution Of Fluid Flow By Axial Dispersion Model

    SciTech Connect (OSTI)

    Sugiharto [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia); Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Su'ud, Zaki; Kurniadi, Rizal; Waris, Abdul [Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Abidin, Zainal [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    2010-12-23T23:59:59.000Z

    Radioactive tracer {sup 82}Br in the form of KBr-82 with activity {+-} 1 mCi has been injected into steel pipeline to qualify the extent dispersion of water flowing inside it. Internal diameter of the pipe is 3 in. The water source was originated from water tank through which the water flow gravitically into the pipeline. Two collimated sodium iodide detectors were used in this experiment each of which was placed on the top of the pipeline at the distance of 8 and 11 m from injection point respectively. Residence time distribution (RTD) curves obtained from injection of tracer are elaborated numerically to find information of the fluid flow properties. The transit time of tracer calculated from the mean residence time (MRT) of each RTD curves is 14.9 s, therefore the flow velocity of the water is 0.2 m/s. The dispersion number, D/uL, for each RTD curve estimated by using axial dispersion model are 0.055 and 0.06 respectively. These calculations are performed after fitting the simulated axial dispersion model on the experiment curves. These results indicated that the extent of dispersion of water flowing in the pipeline is in the category of intermediate.

  1. Flow and axial dispersion in a sinusoidal-walled tube: Effects of inertial and unsteady flows

    SciTech Connect (OSTI)

    Richmond, Marshall C.; Perkins, William A.; Scheibe, Timothy D.; Lambert, Adam; Wood, Brian D.

    2013-12-01T23:59:59.000Z

    Dispersion in porous media flows has been the subject of much experimental, theoretical and numerical study. Here we consider a wavy-walled tube (a three-dimensional tube with sinusoidally-varying diameter) as a simplified conceptualization of flow in porous media, where constrictions represent pore throats and expansions pore bodies. A theoretical model for effective (macroscopic) longitudinal dispersion in this system has been developed by volume averaging the microscale velocity field. Direct numerical simulation using computational fluid dynamics (CFD) methods was used to compute velocity fields by solving the Navier-Stokes equations, and also to numerically solve the volume averaging closure problem, for a range of Reynolds numbers (Re) spanning the low-Re to inertial flow regimes, including one simulation at Re = 449 for which unsteady flow was observed. Dispersion values were computed using both the volume averaging solution and a random walk particle tracking method, and results of the two methods were shown to be consistent. Our results are compared to experimental measurements of dispersion in porous media and to previous theoretical results for the low-Re, Stokes flow regime. In the steady inertial regime we observe an power-law increase in effective longitudinal dispersion (DL) with Re, consistent with previous results. This rapid rate of increase is caused by trapping of solute in expansions due to flow separation (eddies). For the unsteady case (Re = 449), the rate of increase of DL with Re was smaller than that observed at lower Re. Velocity fluctuations in this regime lead to increased rates of solute mass transfer between the core flow and separated flow regions, thus diminishing the amount of tailing caused by solute trapping in eddies and thereby reducing longitudinal dispersion.

  2. Axial dispersion in segmented gas-liquid flow: Effects of alternating channel curvature

    E-Print Network [OSTI]

    Muradoglu, Metin

    processes such as two-phase catalytic monolith reactors,3­6 polymer blow molding, enhanced oil recovery,7 is periodically broken in the serpentine channel leading to enhanced axial dispersion. It is also found channel geometries. In addition to the enhanced mix- ing, the segmentation also reduces the axial

  3. Axial static mixer

    DOE Patents [OSTI]

    Sandrock, H.E.

    1982-05-06T23:59:59.000Z

    Static axial mixing apparatus includes a plurality of channels, forming flow paths of different dimensions. The axial mixer includes a flow adjusting device for adjustable selective control of flow resistance of various flow paths in order to provide substantially identical flows through the various channels, thereby reducing nonuniform coating of interior surfaces of the channels. The flow adjusting device may include diaphragm valves, and may further include a pressure regulating system therefor.

  4. Exit blade geometry and part-load performance of small axial flow propeller turbines: An experimental investigation

    SciTech Connect (OSTI)

    Singh, Punit; Nestmann, Franz [Institute for Water and River Basin Management (IWG), University of Karlsruhe, Kaiser Str. 12, D 76128 Karlsruhe (Germany)

    2010-09-15T23:59:59.000Z

    A detailed experimental investigation of the effects of exit blade geometry on the part-load performance of low-head, axial flow propeller turbines is presented. Even as these turbines find important applications in small-scale energy generation using micro-hydro, the relationship between the layout of blade profile, geometry and turbine performance continues to be poorly characterized. The experimental results presented here help understand the relationship between exit tip angle, discharge through the turbine, shaft power, and efficiency. The modification was implemented on two different propeller runners and it was found that the power and efficiency gains from decreasing the exit tip angle could be explained by a theoretical model presented here based on classical theory of turbomachines. In particular, the focus is on the behaviour of internal parameters like the runner loss coefficient, relative flow angle at exit, mean axial flow velocity and net tangential flow velocity. The study concluded that the effects of exit tip modification were significant. The introspective discussion on the theoretical model's limitation and test facility suggests wider and continued experimentation pertaining to the internal parameters like inlet vortex profile and exit swirl profile. It also recommends thorough validation of the model and its improvement so that it can be made capable for accurate characterization of blade geometric effects. (author)

  5. Computation of the Field in an Axial Gap, Trapped-Flux Type Superconducting Electric Machine

    E-Print Network [OSTI]

    Shen, Zejun; Ainslie, Mark D.; Campbell, Archie M.; Cardwell, David A.

    2014-11-04T23:59:59.000Z

    Abstract—The Bulk Superconductivity Group at the University of Cambridge is currently investigating the use of high temper- ature superconductors in wire and bulk form to increase the electrical and magnetic loading of an axial gap, trapped flux... electric machines are an importantapplication of superconducting materials in both bulk and wire forms. Bulk high temperature superconductors, in partic- ular, are capable of trapping magnetic fields greater than 17 T below 30 K [1], [2], as well as up to 3...

  6. Cylindrically confined pair-ion-electron and pair-ion plasmas having axial sheared flow and radial gradients

    SciTech Connect (OSTI)

    Batool, Nazia; Saleem, H. [National Centre for Physics (NCP), Quaid-i-Azam University Campus, Islamabad (Pakistan)] [National Centre for Physics (NCP), Quaid-i-Azam University Campus, Islamabad (Pakistan)

    2013-10-15T23:59:59.000Z

    The linear and nonlinear dynamics of pair-ion (PI) and pair-ion-electron plasmas (PIE) have been investigated in a cylindrical geometry with a sheared plasma flow along the axial direction having radial dependence. The coupled linear dispersion relation of low frequency electrostatic waves has been presented taking into account the Guassian profile of density and linear gradient of sheared flow. It is pointed out that the quasi-neutral cold inhomogeneous pure pair ion plasma supports only the obliquely propagating convective cell mode. The linear dispersion relation of this mode has been solved using boundary conditions. The nonlinear structures in the form of vortices formed by different waves have been discussed in PI and PIE plasmas.

  7. Evaporative capillary instability for flow in porous media under the influence of axial electric field

    SciTech Connect (OSTI)

    Kumar Awasthi, Mukesh, E-mail: mukeshiitr.kumar@gmail.com [Department of Mathematics, University of Petroleum and Energy Studies, Dehradun (India)

    2014-04-15T23:59:59.000Z

    We study the linear analysis of electrohydrodynamic capillary instability of the interface between two viscous, incompressible and electrically conducting fluids in a fully saturated porous medium, when the phases are enclosed between two horizontal cylindrical surfaces coaxial with the interface and, when there is mass and heat transfer across the interface. The fluids are subjected to a constant electric field in the axial direction. Here, we use an irrotational theory in which the motion and pressure are irrotational and the viscosity enters through the jump in the viscous normal stress in the normal stress balance at the interface. A quadratic dispersion relation that accounts for the growth of axisymmetric waves is obtained and stability criterion is given in terms of a critical value of wave number as well as electric field. It is observed that heat transfer has stabilizing effect on the stability of the considered system while medium porosity destabilizes the interface. The axial electric field has dual effect on the stability analysis.

  8. Suction recirculation and its effects upon axial-flow pump power consumption

    E-Print Network [OSTI]

    Prince, Tony M.

    1983-01-01T23:59:59.000Z

    strainer containing a metal screen cartridge is installed and acts as a water filter. Two gate valves are placed at the suction and the discharge and are used to throttle the flow. Two tubular flow straighteners, made of 1/2 inch diameter copper tubings...

  9. Blade tip clearance effect on the performance and flow field of a three stage axial turbine

    E-Print Network [OSTI]

    Abdel-Fattah, Sharef Aly

    2003-01-01T23:59:59.000Z

    The effect of a 1.5 % blade tip clearance on a rotating three stage turbine under different operating points was investigated using radially and circumferentially traversed five hole pressure probes. The probes were used to obtain flow field total...

  10. Typing Illegal Information Flows as Program Effects Draft

    E-Print Network [OSTI]

    Typing Illegal Information Flows as Program Effects ­ Draft Ana Almeida Matos Instituto de. To this end, sets of illegal information flows are represented as downward closure operators (here referred representations of flexible information flow policies. Illegal information flows can then be seen as program

  11. Typing Illegal Information Flows as Program Effects Ana Almeida Matos

    E-Print Network [OSTI]

    Lisboa, Universidade Técnica de

    Typing Illegal Information Flows as Program Effects Ana Almeida Matos Instituto Superior T labeling. To this end, sets of illegal information flows are represented as downward closure operators (here referred to as flow kernels) on a given lattice of security levels. Illegal information flows can

  12. Experimental study of blade thickness effects on the overall and local performances of a Controlled Vortex Designed axial-flow fan

    E-Print Network [OSTI]

    Boyer, Edmond

    the dissipation of energy in the von K´arm´an street behind the blades so that the per- formances of the fan Vortex Designed axial-flow fan C. Sarrafa , H. Nouria , F. Raveleta, , F. Bakira aArts et Metiers Paris

  13. Suction recirculation and its effects upon axial-flow pump power consumption 

    E-Print Network [OSTI]

    Prince, Tony M.

    1983-01-01T23:59:59.000Z

    1 Test Procedure Outline 2 Section and Pump Critical Flowrates and Speeds. 63 91 3 Power Coefficient and Reynolds Number Based on Cone Radius. 100 4 Power Coefficient and Reynolds Number Based on Surface Area. 101 5 Power Coefficient... Variation with NPSH with Q rl 54 Head Variation with NPSH with Q 2 . r2 55 Head Variation with NPSH with Q 3. r3' 120 128 129 130 131 134 135 136 CHAPTER I INTRODUCTION Pumps of different types are used to displace liquids from one location...

  14. Paper No. 11.02 1 Axial-Compressive Capacities of a New Type of Tapered Steel Pipe Pile at the

    E-Print Network [OSTI]

    Horvath, John S.

    Paper No. 11.02 1 Axial-Compressive Capacities of a New Type of Tapered Steel Pipe Pile at the John driven piles have been the deep foundation of choice at the well-known John F. Kennedy International. For many decades naturally tapered timber piles were used primarily but various brands of closed-end steel

  15. Scalable Low-head Axial-type Venturi-flow Energy Scavenger | 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 DataDepartment of Energy Your Density Isn'tOrigin ofEnergy atLLC - FE DKT. 10-160-LNG -EnergyProcess HeatingatSaw What?

  16. Experimental verification of J. S. Alford's mathematical model that predicts Alford's destabilizing force in axial flow machinery

    E-Print Network [OSTI]

    Laudadio, Frank James

    1981-01-01T23:59:59.000Z

    compressors and turbines causes unbalanced torque forces which, in turn, can cause severe rotor whirl; a rotordynamic instabzlity. In his 1965 paper, "Protecting Turbomachinery from Self Excited Rotor 'whirl", Alford presented the equations to predict... were prominent during operation of the rotors at high pressures and power levels. Alford presents two mechanisms which can cause severe rotor whirl in axial compressors and turbines. One is due to the circumferential variation of static pressure...

  17. Development of large flow-type proportional counters

    E-Print Network [OSTI]

    Torline, Norbert Kevin

    1967-01-01T23:59:59.000Z

    . . )2 13 ~ The minimum efficiency observed in the region of overlap of the proportional counters as a function of the amount of 1'k. Details of the installation of Kovar seal and tungsten wire. . . . . . . . . . . . . . . )8 vii LXST OF TABLES... proportional counters: (i) All counters are of the continuous gas flow-type a- described in the thesis by K. ~&!. Bull. 2 (2) All counters were constructed with brass cathodes and tungsten wire anodes, with bras" end plates and Kovar seal anode leads...

  18. A non-autonomous flow system with Plykin type attractor

    E-Print Network [OSTI]

    Sergey P. Kuznetsov

    2009-01-22T23:59:59.000Z

    A non-autonomous flow system is introduced with an attractor of Plykin type that may serve as a base for elaboration of real systems and devices demonstrating the structurally stable chaotic dynamics. The starting point is a map on a two-dimensional sphere, consisting of four stages of continuous geometrically evident transformations. The computations indicate that in a certain parameter range the map has a uniformly hyperbolic attractor. It may be represented on a plane by means of a stereographic projection. Accounting structural stability, a modification of the model is undertaken to obtain a set of two non-autonomous differential equations of the first order with smooth coefficients. As follows from computations, it has the Plykin type attractor in the Poincar\\'{e} cross-section.

  19. Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY)

    2000-08-29T23:59:59.000Z

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane.

  20. EQUIVARIANT FLOW EQUIVALENCE FOR SHIFTS OF FINITE TYPE, BY MATRIX EQUIVALENCE OVER

    E-Print Network [OSTI]

    Boyle, Mike

    EQUIVARIANT FLOW EQUIVALENCE FOR SHIFTS OF FINITE TYPE, BY MATRIX EQUIVALENCE OVER GROUP RINGS MIKE equivalence of nontrivial irreducible shifts of finite type in terms of (i) elementary equivalence of matrices. In the case G = Z/2, we have the classification for twistwise flow equivalence. We include some algebraic

  1. Stable loosely-coupled-type algorithm for fluid-structure interaction in blood flow

    E-Print Network [OSTI]

    Guidoboni, Giovanna

    Stable loosely-coupled-type algorithm for fluid-structure interaction in blood flow Giovanna Abstract We introduce a novel loosely coupled-type algorithm for fluid-structure interaction between blood. A major application is blood flow in human arteries. Understanding fluid- structure interaction between

  2. The effect of spacer ribs on Ledinegg type flow instabilities

    SciTech Connect (OSTI)

    Coutts, D.A.

    1993-09-09T23:59:59.000Z

    An experimental program has been completed which evaluated the effect of a flow obstruction in a heated channel on the onset of flow instability (OBI). The test channel was rectangular (80 {times} 3 mm), heated on one surface, and equipped with view ports. Tests were conducted in a flow controlled mode at heat fluxes of 370 kW/M{sup 2}, and 610 kW/m{sup 2}. Direct comparisons were made between the demand curve minimum for the unobstructed channel and a channel equipped with a 2.07 mm wide rib that was parallel to the flow and in contact with the heated surface. Data at OFI is presented in the nondimensional terms Of Q{sub ratio} (ratio of heat flux applied to heat flux required to achieve saturated liquid conditions at the exit), and the local Stanton number at the channel exit for each channel arrangement. The Q{sub ratio} and Stanton number values for the unobstructed channel and the rib equipped channel are then compared to produce an estimate of the rib effect.

  3. Crossflow instability in rotor-stator flows with throughflow , M.-P. Chauve

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Crossflow instability in rotor-stator flows with throughflow S. Poncet , M.-P. Chauve We study. As the axial velocity profiles exhibit inflexion points, this instability is of crossflow type. From

  4. EQUIVARIANT FLOW EQUIVALENCE FOR SHIFTS OF FINITE TYPE, BY MATRIX EQUIVALENCE OVER

    E-Print Network [OSTI]

    Sullivan, Michael

    EQUIVARIANT FLOW EQUIVALENCE FOR SHIFTS OF FINITE TYPE, BY MATRIX EQUIVALENCE OVER GROUP RINGS MIKE equivalence of nontrivial irreducible shifts of #12;nite type in terms of (i) elementary equivalence vertex. In the case G = Z=2, we have the classi#12;cation for twistwise ow equivalence. We include some

  5. Flow Characteristics Analysis of Widows' Creek Type Control Valve for Steam Turbine Control

    SciTech Connect (OSTI)

    Yoo, Yong H.; Sohn, Myoung S.; Suh, Kune Y. [PHILOSOPHIA, Inc., Seoul National University, San 56-1 Sillim-dong, Gwanak-gu, Seoul, 151-742 (Korea, Republic of)

    2006-07-01T23:59:59.000Z

    The steam turbine converts the kinetic energy of steam to mechanical energy of rotor blades in the power conversion system of fossil and nuclear power plants. The electric output from the generator of which the rotor is coupled with that of the steam turbine depends on the rotation velocity of the steam turbine bucket. The rotation velocity is proportional to the mass flow rate of steam entering the steam turbine through valves and nozzles. Thus, it is very important to control the steam mass flow rate for the load following operation of power plants. Among various valves that control the steam turbine, the control valve is most significant. The steam flow rate is determined by the area formed by the stem disk and the seat of the control valve. While the ideal control valve linearly controls the steam mass flow rate with its stem lift, the real control valve has various flow characteristic curves pursuant to the stem lift type. Thus, flow characteristic curves are needed to precisely design the control valves manufactured for the operating conditions of nuclear power plants. OMEGA (Optimized Multidimensional Experiment Geometric Apparatus) was built to experimentally study the flow characteristics of steam flowing inside the control valve. The Widows' Creek type control valve was selected for reference. Air was selected as the working fluid in the OMEGA loop to exclude the condensation effect in this simplified approach. Flow characteristic curves were plotted by calculating the ratio of the measured mass flow rate versus the theoretical mass flow rate of the air. The flow characteristic curves are expected to be utilized to accurately design and operate the control valve for fossil as well as nuclear plants. (authors)

  6. Measuring axial pump thrust

    DOE Patents [OSTI]

    Suchoza, B.P.; Becse, I.

    1988-11-08T23:59:59.000Z

    An apparatus for measuring the hydraulic axial thrust of a pump under operation conditions is disclosed. The axial thrust is determined by forcing the rotating impeller off of an associated thrust bearing by use of an elongate rod extending coaxially with the pump shaft. The elongate rod contacts an impeller retainer bolt where a bearing is provided. Suitable measuring devices measure when the rod moves to force the impeller off of the associated thrust bearing and the axial force exerted on the rod at that time. The elongate rod is preferably provided in a housing with a heat dissipation mechanism whereby the hot fluid does not affect the measuring devices. 1 fig.

  7. Measuring axial pump thrust

    DOE Patents [OSTI]

    Suchoza, Bernard P. (McMurray, PA); Becse, Imre (Washington, PA)

    1988-01-01T23:59:59.000Z

    An apparatus for measuring the hydraulic axial thrust of a pump under operation conditions is disclosed. The axial thrust is determined by forcing the rotating impeller off of an associated thrust bearing by use of an elongate rod extending coaxially with the pump shaft. The elongate rod contacts an impeller retainer bolt where a bearing is provided. Suitable measuring devices measure when the rod moves to force the impeller off of the associated thrust bearing and the axial force exerted on the rod at that time. The elongate rod is preferably provided in a housing with a heat dissipation mechanism whereby the hot fluid does not affect the measuring devices.

  8. Development of flow network analysis code for block type VHTR core by linear theory method

    SciTech Connect (OSTI)

    Lee, J. H.; Yoon, S. J. [Dept. of Nuclear Engr., Seoul National Univ., Daehak-dong, Gwanak-gu, Seoul, 151-742 (Korea, Republic of); Park, J. W. [Dept. of Nuclear and Energy Engr, Dongguk Univ., Seokjang-Dong, Gyeongju, Gyeongsangbuk-Do, 780-714 (Korea, Republic of); Park, G. C. [Dept. of Nuclear Engr., Seoul National Univ., Daehak-dong, Gwanak-gu, Seoul, 151-742 (Korea, Republic of)

    2012-07-01T23:59:59.000Z

    VHTR (Very High Temperature Reactor) is high-efficiency nuclear reactor which is capable of generating hydrogen with high temperature of coolant. PMR (Prismatic Modular Reactor) type reactor consists of hexagonal prismatic fuel blocks and reflector blocks. The flow paths in the prismatic VHTR core consist of coolant holes, bypass gaps and cross gaps. Complicated flow paths are formed in the core since the coolant holes and bypass gap are connected by the cross gap. Distributed coolant was mixed in the core through the cross gap so that the flow characteristics could not be modeled as a simple parallel pipe system. It requires lot of effort and takes very long time to analyze the core flow with CFD analysis. Hence, it is important to develop the code for VHTR core flow which can predict the core flow distribution fast and accurate. In this study, steady state flow network analysis code is developed using flow network algorithm. Developed flow network analysis code was named as FLASH code and it was validated with the experimental data and CFD simulation results. (authors)

  9. A Transonic Axial Compressor Facility for Fundamental Research

    E-Print Network [OSTI]

    Morris, Scott C.

    A Transonic Axial Compressor Facility for Fundamental Research and Flow Control Development Joshua, IN, 46556, USA A single-stage transonic axial compressor facility has been constructed in the the current generation of aero-gas turbine engines. The compressor stage and facility were designed

  10. Pinch-type instability experiments in magnetic Taylor-Couette flows

    E-Print Network [OSTI]

    Pinch-type instability experiments in magnetic Taylor-Couette flows G. R¨udiger1 and D.A. Shalybkov.F. Ioffe Institute of Physics and Technology, 194021 St. Petersburg, Russia E-mail: gruediger enough Hartmann numbers the toroidal field is always (pinch-)unstable independent of any details

  11. 44 (2007-5) Fig.1 Exploded view of a radial-flow-type combustor.

    E-Print Network [OSTI]

    Kasagi, Nobuhide

    44 (2007-5) Fig.1 Exploded view of a radial-flow-type combustor. On Catalyst Deployment for Uniform Temperature Distribution in Micro Ceramic Combustor * Takashi OKAMASA, Yuji SUZUKI and Nobuhide KASAGI catalytic combustor using high-precision ceramic tape-casting technology for micro thermophotovoltaic system

  12. A Viscosity Approach to Total Variation Flows of Non-Divergence Type

    E-Print Network [OSTI]

    Ishii, Hitoshi

    A Viscosity Approach to Total Variation Flows of Non-Divergence Type Norbert Poz´ar Graduate School, we will introduce a notion of viscosity solutions for a class of singular nonlinear parabolic viscosity theory does not apply is the unboundedness of the operator on the right-hand side of (5) at u = 0

  13. Molecular-Flow Properties of RIB Type Vapor-Transport Systems Using a Fast-Valve

    SciTech Connect (OSTI)

    Alton, Gerald D [ORNL] [ORNL; Bilheux, Hassina Z [ORNL] [ORNL; Zhang, Y. [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Liu, Yuan [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    The advent of the fast-valve device, described previously, permits measurement of molecular-flow times of chemically active or inactive gaseous species through radioactive ion beam (RIB) target ion source systems, independent of size, geometry and materials of construction. Thus, decay losses of short-half-life RIBs can be determined for a given target/vapor-transport system in advance of on-line operation, thereby ascertaining the feasibility of the system design for successful processing of a given isotope. In this article, molecular-flow-time theory and experimentally measured molecular-flow time data are given for serial- and parallel-coupled Ta metal RIB vapor-transport systems similar to those used at ISOL based RIB facilities. In addition, the effect of source type on the molecular-flow time properties of a given system is addressed, and a chemical passivation method for negating surface adsorption enthalpies for chemically active gaseous species on Ta surfaces is demonstrated.

  14. Performance of An Axial Gas Ionization Detector

    E-Print Network [OSTI]

    S. Adhikari; C. Basu; C. Samanta; S. S. Brahmachari; B. P. Das; P. Basu

    2006-10-11T23:59:59.000Z

    An axial gas ionization chamber has been fabricated for use as a $\\Delta E$ detector in heavy ion induced nuclear reactions. Different operating parameters such as gas type, pressure, anode voltage and anode structures have been optimized. The transparency of the anode structure is observed to play an important role in improving the energy resolution of the detector.

  15. Comparison of entropy production rates in two different types of self-organized flows: Benard convection and zonal flow

    SciTech Connect (OSTI)

    Kawazura, Y.; Yoshida, Z. [Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba 277-8561 (Japan)

    2012-01-15T23:59:59.000Z

    Two different types of self-organizing and sustaining ordered motion in fluids or plasmas--one is a Benard convection (or streamer) and the other is a zonal flow--have been compared by introducing a thermodynamic phenomenological model and evaluating the corresponding entropy production rates (EP). These two systems have different topologies in their equivalent circuits: the Benard convection is modeled by parallel connection of linear and nonlinear conductances, while the zonal flow is modeled by series connection. The ''power supply'' that drives the systems is also a determinant of operating modes. When the energy flux is a control parameter (as in usual plasma experiments), the driver is modeled by a constant-current power supply, and when the temperature difference between two separate boundaries is controlled (as in usual computational studies), the driver is modeled by a constant-voltage power supply. The parallel (series)-connection system tends to minimize (maximize) the total EP when a constant-current power supply drives the system. This minimum/maximum relation flips when a constant-voltage power supply is connected.

  16. Feedback control of inertial microfluidics using axial control forces

    E-Print Network [OSTI]

    Prohm, Christopher

    2014-01-01T23:59:59.000Z

    Inertial microfluidics is a promising tool for many lab-on-a-chip applications. Particles in channel flows with Reynolds numbers above one undergo cross-streamline migration to a discrete set of equilibrium positions in square and rectangular channel cross sections. This effect has been used extensively for particle sorting and the analysis of particle properties. Using the lattice Boltzmann method, we determine equilibrium positions in square and rectangular cross sections and classify their types of stability for different Reynolds numbers, particle sizes, and channel aspect ratios. Our findings thereby help to design microfluidic channels for particle sorting. Furthermore, we demonstrate how an axial control force, which slows down the particles, shifts the stable equilibrium position towards the channel center. Ultimately, the particles then stay on the centerline for forces exceeding a threshold value. This effect is sensitive to particle size and channel Reynolds number and therefore suggests an efficie...

  17. Decomposition of cumyl hydroperoxide in the presence of sulphonated silica in a flow-type system

    SciTech Connect (OSTI)

    Shelpakova, N.A.; Ioffa, A.F.

    1993-12-31T23:59:59.000Z

    An investigation has been made of the decomposition of cumyl hydroperoxide (CHP) in the presence of silica-based sulphocationites in a flow-type system. It was established that the given specimens are effective catalysts for the decomposition of CHP into phenol and acetone. It was shown that, in the course of the process, no irreversible poisoning of the surface of the catalyst by the products of CHP decomposition occurs. Data of chromatographic analysis of the products of CHP decomposition in the presence of sulphuric acid and silica-based sulphocationites are given.

  18. Type 2 diabetes severely impairs structural and functional adaptation of rat resistance arteries to chronic changes in blood flow

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Type 2 diabetes severely impairs structural and functional adaptation of rat resistance arteries : Diabetes impairs flow-mediated remodeling Address for Correspondence: Dr. Daniel Henrion, Pharm.D., Ph damages in type 2 diabetes. The capacity of the microcirculation to adapt or remodel in response

  19. Scalable control program for multiprecursor flow-type atomic layer deposition system

    SciTech Connect (OSTI)

    Selvaraj, Sathees Kannan [Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607 (United States); Takoudis, Christos G., E-mail: takoudis@uic.edu [Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607 and Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois 60607 (United States)

    2015-01-01T23:59:59.000Z

    The authors report the development and implementation of a scalable control program to control flow type atomic layer deposition (ALD) reactor with multiple precursor delivery lines. The program logic is written and tested in LABVIEW environment to control ALD reactor with four precursor delivery lines to deposit up to four layers of different materials in cyclic manner. The programming logic is conceived such that to facilitate scale up for depositing more layers with multiple precursors and scale down for using single layer with any one precursor in the ALD reactor. The program takes precursor and oxidizer exposure and purging times as input and controls the sequential opening and closing of the valves to facilitate the complex ALD process in cyclic manner. The program could be used to deposit materials from any single line or in tandem with other lines in any combination and in any sequence.

  20. Small core axial compressors for high efficiency jet aircraft

    E-Print Network [OSTI]

    DiOrio, Austin Graf

    2012-01-01T23:59:59.000Z

    This thesis quantifies mechanisms that limit efficiency in small core axial compressors, defined here as compressor exit corrected flow between 1.5 and 3.0 lbm/s. The first part of the thesis describes why a small engine ...

  1. Three-dimensional turbulent swirling flow in a cylinder: Experiments and computations

    E-Print Network [OSTI]

    Gupta, Amit

    is cycloning, where particles are separated from a fluid owing to centrifugal forces imparted by a swirling axial. But a few cylin- drical cyclones of the type described here have been used to separate liquid Abstract Dynamics of the three-dimensional flow in a cyclone with tangential inlet and tangential exit were

  2. Feedback control of inertial microfluidics using axial control forces

    E-Print Network [OSTI]

    Christopher Prohm; Holger Stark

    2014-02-03T23:59:59.000Z

    Inertial microfluidics is a promising tool for many lab-on-a-chip applications. Particles in channel flows with Reynolds numbers above one undergo cross-streamline migration to a discrete set of equilibrium positions in square and rectangular channel cross sections. This effect has been used extensively for particle sorting and the analysis of particle properties. Using the lattice Boltzmann method, we determine equilibrium positions in square and rectangular cross sections and classify their types of stability for different Reynolds numbers, particle sizes, and channel aspect ratios. Our findings thereby help to design microfluidic channels for particle sorting. Furthermore, we demonstrate how an axial control force, which slows down the particles, shifts the stable equilibrium position towards the channel center. Ultimately, the particles then stay on the centerline for forces exceeding a threshold value. This effect is sensitive to particle size and channel Reynolds number and therefore suggests an efficient method for particle separation. In combination with a hysteretic feedback scheme, we can even increase particle throughput.

  3. A note on axial symmetries

    E-Print Network [OSTI]

    Christopher Beetle; Shawn Wilder

    2013-12-31T23:59:59.000Z

    This note describes a local scheme to characterize and normalize an axial Killing field on a general Riemannian geometry. No global assumptions are necessary, such as that the orbits of the Killing field all have period $2 \\pi$. Rather, any Killing field that vanishes at at least one point necessarily has the expected global properties.

  4. Cyclone reactor with internal separation and axial recirculation

    DOE Patents [OSTI]

    Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA)

    1989-01-01T23:59:59.000Z

    A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combuston chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture of flue gas and ash may be tangentially withdrawn from the outlet end of the combustor chamber and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture.

  5. Cyclone reactor with internal separation and axial recirculation

    DOE Patents [OSTI]

    Becker, F.E.; Smolensky, L.A.

    1988-07-19T23:59:59.000Z

    A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture is described. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combustor chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture may be tangentially withdrawn from the outlet end and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture. 10 figs.

  6. Axially staggered seed-blanket reactor-fuel-module construction. [LWBR

    DOE Patents [OSTI]

    Cowell, G.K.; DiGuiseppe, C.P.

    1982-10-28T23:59:59.000Z

    A heterogeneous nuclear reactor of the seed-blanket type is provided wherein the fissile (seed) and fertile (blanket) nuclear fuels are segregated axially within each fuel element such that fissile and fertile regions occur in an alternating pattern along the length of the fuel element. Further, different axial stacking patterns are used for the fuel elements of at least two module types such that when modules of different types are positioned adjacent to one another, the fertile regions of the modules are offset or staggered. Thus, when a module of one type is surrounded by modules of the second type the fertile regions thereof will be surrounded on all sides by fissile material. This provides enhanced neutron communication both radially and axially, thereby resulting in greater power oscillation stability than other axial arrangements.

  7. Numerical analysis of a microwave torch with axial gas injection

    SciTech Connect (OSTI)

    Gritsinin, S. I.; Davydov, A. M.; Kossyi, I. A., E-mail: kossyi@fpl.gpi.ru [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation); Kulumbaev, E. B. [National Research University Belgorod State University (Russian Federation)] [National Research University Belgorod State University (Russian Federation); Lelevkin, V. M. [Kyrgyz-Russian Slavic University (Kyrgyzstan)] [Kyrgyz-Russian Slavic University (Kyrgyzstan)

    2013-07-15T23:59:59.000Z

    The characteristics of a microwave discharge in an argon jet injected axially into a coaxial channel with a shortened inner electrode are numerically analyzed using a self-consistent equilibrium gas-dynamic model. The specific features of the excitation and maintenance of the microwave discharge are determined, and the dependences of the discharge characteristics on the supplied electromagnetic power and gas flow rate are obtained. The calculated results are compared with experimental data.

  8. Experimental Study of Heat Transfer and Flow Characteristics for a New Type of Air Heater

    E-Print Network [OSTI]

    Zheng, H.; Fan, X.; Li, A.

    2006-01-01T23:59:59.000Z

    . It is found that the integrated characteristics of heat transfer and flow friction increase with the hole's diameter at the same hole density (which is equal to the ratio of the hole's total area to the baffle's area), and the heat transfer rate increases...

  9. Experimental Study of Heat Transfer and Flow Characteristics for a New Type of Air Heater 

    E-Print Network [OSTI]

    Zheng, H.; Fan, X.; Li, A.

    2006-01-01T23:59:59.000Z

    . It is found that the integrated characteristics of heat transfer and flow friction increase with the hole's diameter at the same hole density (which is equal to the ratio of the hole's total area to the baffle's area), and the heat transfer rate increases...

  10. Multi-axial fracture behaviour of notched carbon-fibre/epoxy laminates

    E-Print Network [OSTI]

    Tan, Julian Lip Yi

    2015-04-28T23:59:59.000Z

    conditions in structural systems such as aircrafts and automobiles has immensely motivated the development of controlled multi-axial and biaxial loading tests. According to Chen & Matthews (1993), two main types of specimens are used for combined loading...

  11. Experimental on two sensors combination used in horizontal pipe gas-water two-phase flow

    SciTech Connect (OSTI)

    Wu, Hao; Dong, Feng [Tianjin Key Laboratory of Process Measurement and Control, School of Electrical Engineering and Automation, Tianjin University, Tianjin (China)

    2014-04-11T23:59:59.000Z

    Gas-water two phase flow phenomenon widely exists in production and living and the measurement of it is meaningful. A new type of long-waist cone flow sensor has been designed to measure two-phase mass flow rate. Six rings structure of conductance probe is used to measure volume fraction and axial velocity. The calibration of them have been made. Two sensors have been combined in horizontal pipeline experiment to measure two-phase flow mass flow rate. Several model of gas-water two-phase flow has been discussed. The calculation errors of total mass flow rate measurement is less than 5% based on the revised homogeneous flow model.

  12. Axial interaction free-electron laser

    DOE Patents [OSTI]

    Carlsten, Bruce E. (Los Alamos, NM)

    1997-01-01T23:59:59.000Z

    Electron orbits from a helical axial wiggler in an axial guide field are absolutely unstable as power is extracted from the particles. For off-axis beams an axial FEL mechanism exists when the axial electric field in a TM mode is wiggled to interact with the axial velocity of the electrons that form the beam. The interaction strength is comparable to that for helical FELs and is insensitive to beam orbit errors. The orbits for this mechanism are extremely stable in the absence of space charge and lead to high extraction efficiencies without particle phasing incoherence or interception. This interaction mechanism is suitable for use with intense annular electron beams for high power generation at microwave frequencies.

  13. Axial interaction free-electron laser

    DOE Patents [OSTI]

    Carlsten, B.E.

    1997-09-02T23:59:59.000Z

    Electron orbits from a helical axial wiggler in an axial guide field are absolutely unstable as power is extracted from the particles. For off-axis beams an axial FEL mechanism exists when the axial electric field in a TM mode is wiggled to interact with the axial velocity of the electrons that form the beam. The interaction strength is comparable to that for helical FELs and is insensitive to beam orbit errors. The orbits for this mechanism are extremely stable in the absence of space charge and lead to high extraction efficiencies without particle phasing incoherence or interception. This interaction mechanism is suitable for use with intense annular electron beams for high power generation at microwave frequencies. 5 figs.

  14. Investigation of Non-synchronous Vibration Mechanism for a High Speed Axial Compressor Using Delayed DES

    E-Print Network [OSTI]

    Zha, Gecheng

    Investigation of Non-synchronous Vibration Mechanism for a High Speed Axial Compressor Using compressor. DDES is a hybrid model for turbulence simulation, which uses RANS model within the wall boundary of the compressor occurs due to the rotating flow instability in the vicinity of the rotor tip at a stable operation

  15. Instability inside a rotating gas cylinder subject to axial periodic strain Y. Duguet,a

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of viscous flow inside a closed circular cylinder rotating about its axis, periodically compressed by meansInstability inside a rotating gas cylinder subject to axial periodic strain Y. Duguet,a J. F. Scott are known to support inertial oscillations whose frequencies are less than twice the basic rotation rate.1

  16. Performance limits of axial turbomachine stages

    E-Print Network [OSTI]

    Hall, David Kenneth

    2011-01-01T23:59:59.000Z

    This thesis assesses the limits of stage efficiency for axial compressor and turbine stages. A stage model is developed, consisting of a specified geometry and a surface velocity distribution with turbulent boundary layers. ...

  17. axial piston type: Topics by E-print Network

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

    functions of n low order Ceragioli, Francesca 114 The Green Potential of Free-Piston Stirling Engines Engineering Websites Summary: a distillate fuel like gasoline and can...

  18. axial flow compressors: Topics by E-print Network

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

    compressor performance Peraire, Jaime 126 FEASIBILITY OF SOLAR-FIRED, COMPRESSOR-ASSISTED Energy Storage, Conversion and Utilization Websites Summary: FEASIBILITY OF...

  19. axial flow compressor: Topics by E-print Network

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

    compressor performance Peraire, Jaime 126 FEASIBILITY OF SOLAR-FIRED, COMPRESSOR-ASSISTED Energy Storage, Conversion and Utilization Websites Summary: FEASIBILITY OF...

  20. axial flow turbines: Topics by E-print Network

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

    Carver, Jeffrey C. 176 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  1. axial flow turbine: Topics by E-print Network

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

    Carver, Jeffrey C. 176 Development of a catalytic combustion system for the MIT Micro Gas Turbine Engine MIT - DSpace Summary: As part of the MIT micro-gas turbine engine...

  2. Nucleon Axial Form Factor from Lattice QCD

    E-Print Network [OSTI]

    Liu, K F; Draper, T; Wu, J M; Wilcox, W

    1994-01-01T23:59:59.000Z

    Results for the isovector axial form factors of the proton from a lattice QCD calculation are presented for both point-split and local currents. They are obtained on a quenched $16^{3} \\times 24$ lattice at $\\beta= 6.0$ with Wilson fermions for a range of quark masses from strange to charm. We determine the finite lattice renormalization for both the local and point-split currents of heavy quarks. Results extrapolated to the chiral limit show that the $q^2$ dependence of the axial form factor agrees reasonably well with experiment. The axial coupling constant $g_A$ calculated for the local and the point-split currents is about 6\\% and 12\\% smaller than the experimental value respectively.

  3. IMPACT OF PRESSURE EQUALIZATION SLOT IN FLOW CHANNEL INSERT ON TRITIUM TRANSPORT IN A DCLL-TYPE POLOIDAL DUCT

    E-Print Network [OSTI]

    Abdou, Mohamed

    -TYPE POLOIDAL DUCT H. Zhang, A. Ying, M. Abdou Mechanical and Aerospace Engineering Dept., UCLA, Los Angeles, CA

  4. Simulation of in-core neutron noise measurements for axial void profile reconstruction in boiling water reactors

    SciTech Connect (OSTI)

    Dykin, V.; Pazsit, I. [Chalmers Univ. of Technology, Div. of Nuclear Engineering, Dept. of Applied Physics, SE-412 96 Gothenburg (Sweden)

    2012-07-01T23:59:59.000Z

    A possibility to reconstruct the axial void profile from the simulated in-core neutron noise which is caused by density fluctuations in a Boiling Water Reactor (BWR) heated channel is considered. For this purpose, a self-contained model of the two-phase flow regime is constructed which has quantitatively and qualitatively similar properties to those observed in real BWRs. The model is subsequently used to simulate the signals of neutron detectors induced by the corresponding perturbations in the flow density. The bubbles are generated randomly in both space and time using Monte-Carlo techniques. The axial distribution of the bubble production is chosen such that the mean axial void fraction and void velocity follow the actual values of BWRs. The induced neutron noise signals are calculated and then processed by the standard signal analysis methods such as Auto-Power Spectral Density (APSD) and Cross-Power Spectral Density (CPSD). Two methods for axial void and velocity profiles reconstruction are discussed: the first one is based on the change of the break frequency of the neutron auto-power spectrum with axial core elevation, while the second refers to the estimation of transit times of propagating steam fluctuations between different axial detector positions. This paper summarizes the principles of the model and presents a numerical testing of the qualitative applicability to estimate the required parameters for the reconstruction of the void fraction profile from the neutron noise measurements. (authors)

  5. Co-axial, high energy gamma generator

    DOE Patents [OSTI]

    Reijonen, Jani Petteri (Princeton, NJ); Gicquel, Frederic (Pennington, NJ)

    2011-08-16T23:59:59.000Z

    A gamma ray generator includes an ion source in a first chamber. A second chamber is configured co-axially around the first chamber at a lower second pressure. Co-axially arranged plasma apertures separate the two chambers and provide for restricted passage of ions and gas from the first to the second chamber. The second chamber is formed by a puller electrode having at least one long channel aperture to draw ions from the first chamber when the puller electrode is subject to an appropriate applied potential. A plurality of electrodes rings in the third chamber in third pressure co-axially surround the puller electrode and have at least one channel corresponding to the at least one puller electrode aperture and plasma aperture. The electrode rings increase the energy of the ions to a selected energy in stages in passing between successive pairs of the electrodes by application of an accelerating voltage to the successive pairs of accelerator electrodes. A target disposed co-axially around the plurality of electrodes receives the beam of accelerated ions, producing gamma rays.

  6. Reducing axial offset and improving stability in PWRs by using uraniumethorium fuel

    E-Print Network [OSTI]

    Demazière, Christophe

    Reducing axial offset and improving stability in PWRs by using uraniumethorium fuel Cheuk Wah Lau a that a new type uraniumethorium (UeTh) based fuel assembly could be used to achieve a more homogenous radial that a core containing UeTh fuel assemblies also reduces the AO and improves the core stability

  7. Description of Axial Detail for ROK Fuel

    SciTech Connect (OSTI)

    Trellue, Holly R [Los Alamos National Laboratory; Galloway, Jack D [Los Alamos National Laboratory

    2012-04-20T23:59:59.000Z

    For the purpose of NDA simulations of the ROK fuel assemblies, we have developed an axial burnup distribution to represent the pins themselves based on gamma scans of rods in the G23 assembly. For the purpose of modeling the G23 assembly (both at ORNL and LANL), the pin-by-pin burnup map as simulated by ROK is being assumed to represent the radial burnup distribution. However, both DA and NDA results indicate that this simulated estimate is not 100% correct. In particular, the burnup obtained from the axial gamma scan of 7 pins does not represent exactly the same 'average' pin burnup as the ROK simulation. Correction for this discrepancy is a goal of the well-characterized assembly task but will take time. For now, I have come up with a correlation for 26 axial points of the burnup as obtained by gamma scans of 7 different rods (C13, G01, G02, J11, K10, L02, and M04, neglecting K02 at this time) to the average burnup given by the simulation for each of the rods individually. The resulting fraction in each axial zone is then averaged for the 7 different rods so that it can represent every fuel pin in the assembly. The burnup in each of the 26 axial zones of rods in all ROK assemblies will then be directly adjusted using this fraction, which is given in Table 1. Note that the gamma scan data given by ROK for assembly G23 included a length of {approx}3686 mm, so the first 12 mm and the last 14 mm were ignored to give an actual rod length of {approx}366 cm. To represent assembly F02 in which no pin-by-pin burnup distribution is given by ROK, we must model it using infinitely-reflected geometry but can look at the effects of measuring in different axial zones by using intermediate burnup files (i.e. smaller burnups than 28 GWd/MTU) and determining which axial zone(s) each burnup represents. Details for assembly F02 are then given in Tables 2 and 3, which is given in Table 1 and has 44 total axial zones to represent the top meter in explicit detail in addition to the other 26 zones. Note that the MCNP files for F02 were created using the Monte Carlo burnup linkage code Monteburns, which saves MCNP input files with detailed compositions as a function of burnup. The 'intermediate burnup files' produced for F02 include a cooling time of 27 years. The axial location of 5 spacers was also included in the ROK F02 assembly in which each spacer contained a length of 3.81 cm. Note that due to the nature of Monteburns, which was run in a special fashion for this problem, the step number increments after the 27 year decay, so the second column of Table 2 refers to the step number that should be used in the Monteburns files.

  8. Review of Axial Burnup Distribution Considerations for Burnup Credit Calculations

    SciTech Connect (OSTI)

    Wagner, J.C.; DeHart, M.D.

    2000-03-01T23:59:59.000Z

    This report attempts to summarize and consolidate the existing knowledge on axial burnup distribution issues that are important to burnup credit criticality safety calculations. Recently released Nuclear Regulatory Commission (NRC) staff guidance permits limited burnup credit, and thus, has prompted resolution of the axial burnup distribution issue. The reactivity difference between the neutron multiplication factor (keff) calculated with explicit representation of the axial burnup distribution and keff calculated assuming a uniform axial burnup is referred to as the ``end effect.'' This end effect is shown to be dependent on many factors, including the axial-burnup profile, total accumulated burnup, cooling time, initial enrichment, assembly design, and the isotopics considered (i.e., actinide-only or actinides plus fission products). Axial modeling studies, efforts related to the development of axial-profile databases, and the determination of bounding axial profiles are also discussed. Finally, areas that could benefit from further efforts are identified.

  9. Field Examples of Axial Cracked Bearings in Wind Turbine Gearboxes...

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

    Field Examples of Axial Cracked Bearings in Wind Turbine Gearboxes Presented by Paul John Baker of FrontierPro Services at the Wind Turbine Tribology Seminar 2014. 141030 Axial...

  10. A novel target-type low pressure drop bidirectional optoelectronic air flow sensor for infant artificial ventilation: Measurement principle and static calibration

    SciTech Connect (OSTI)

    Saccomandi, Paola; Schena, Emiliano; Silvestri, Sergio [Faculty of Biomedical Engineering, University Campus Bio-Medico, Via Alvaro del Portillo, 21, 00128 Rome (Italy)

    2011-02-15T23:59:59.000Z

    An optoelectronic target-type volumetric air flow-rate transducer for bidirectional measurements is presented. The sensor is composed of a T-shaped target and two nominally identical LED-photodiode couples which are operated in differential mode. The sensitive surfaces of the photodiodes are differentially shadowed by the deflection of the target, which in turn depends on the gas flow-rate. The principle of operation is described in mathematical terms and the design parameters have been optimized in order to obtain the highest sensitivity along with minimal pressure drop and reduced dimensions. The sensor is placed in a 20 mm diameter hose and was tested with air flow-rate in the typical temperature range of mechanical ventilation between 20 and 40 deg. C. The theoretical model was validated through experiments carried out in the volumetric flow range from -7.0 to +7.0 l min{sup -1}. The nonlinear behavior allows sensitivities equal to 0.6 V l{sup -1} min for flow rates ranging from -2.0 to +2.0 l min{sup -1}, equal to 2.0 V l{sup -1} min for flow rates ranging from -3.0 to -2.0 l min{sup -1} and from +2.0 to +3.0 l min{sup -1}, up to 5.7 V l{sup -1} min at higher flow rates ranging from -7.0 to -3.0 l min{sup -1} and from +3.0 to +7.0 l min{sup -1}. The linear range extends from 3.0 to 7.0 l min{sup -1} with constant sensitivity equal to 5.7 V l{sup -1} min. The sensor is able to detect a flow-rate equal to 1.0 l min{sup -1} with a sensitivity of about 400 mV l{sup -1} min. The differential nature of the output minimizes the influence of the LEDs' power supply variations and allows to obtain a repeatability in the order of 3% of full scale output. The small pressure drop produced by the sensor placed in-line the fluid stream, of about 2.4 Pa at 7 l min{sup -1}, corresponds to a negligible fluid dynamic resistance lower than 0.34 Pa l{sup -1} min.

  11. Simulations on the Nonlinear Mode Coupling in Multiple-scale Drift-type Turbulence with Coherent Flow Structures

    E-Print Network [OSTI]

    Lin, Zhihong

    coupling, the same back-action process can deform the spectral distribution in inertia range from the powerTH/2-31 Simulations on the Nonlinear Mode Coupling in Multiple-scale Drift-type Turbulence@energy.kyoto-u.ac.jp Abstract: The dynamics of secondary, anisotropic coherent structures behaving as a stationary wave

  12. Gravitational waves from a test particle scattered by a neutron star: Axial mode case

    E-Print Network [OSTI]

    Kazuhiro Tominaga; Motoyuki Saijo; Kei-ichi Maeda

    1999-09-20T23:59:59.000Z

    Using a metric perturbation method, we study gravitational waves from a test particle scattered by a spherically symmetric relativistic star. We calculate the energy spectrum and the waveform of gravitational waves for axial modes. Since metric perturbations in axial modes do not couple to the matter fluid of the star, emitted waves for a normal neutron star show only one peak in the spectrum, which corresponds to the orbital frequency at the turning point, where the gravitational field is strongest. However, for an ultracompact star (the radius $R \\lesssim 3M$), another type of resonant periodic peak appears in the spectrum. This is just because of an excitation by a scattered particle of axial quasinormal modes, which were found by Chandrasekhar and Ferrari. This excitation comes from the existence of the potential minimum inside of a star. We also find for an ultracompact star many small periodic peaks at the frequency region beyond the maximum of the potential, which would be due to a resonance of two waves reflected by two potential barriers (Regge-Wheeler type and one at the center of the star). Such resonant peaks appear neither for a normal neutron star nor for a Schwarzschild black hole. Consequently, even if we analyze the energy spectrum of gravitational waves only for axial modes, it would be possible to distinguish between an ultracompact star and a normal neutron star (or a Schwarzschild black hole).

  13. Three-dimensional rotating stall inception and effects of rotating tip clearance asymmetry in axial compressors

    E-Print Network [OSTI]

    Gordon, Kenneth A. (Kenneth Andrew), 1970-

    1999-01-01T23:59:59.000Z

    The effects of two types of flow nonuniformity on stall inception behavior were assessed with linearized stability analyses of two compressor flow models. Response to rotating tip clearance asymmetries induced by a whirling ...

  14. Genetic pore typing as a means of characterizing reservoir flow units: san andres, sunflower field, terry country, texas 

    E-Print Network [OSTI]

    Humbolt, Aubrey Nicole

    2009-05-15T23:59:59.000Z

    . Poroperm values, measured petrophysical data, stratigraphic architecture, lithofacies, and genetic pore types from Sunflower field will be used to test pre-existing and modified techniques of reservoir characterization. From the resulting analysis, a... a depth of 5,300 feet. Sunflower pay is composed of several stacked, laterally continuous, high frequency cycles defined herein as parasequences. Dolomite, anhydritic dolomite, and thin bedded anhydrite serve as dominant facies although minor lime...

  15. Development of a full-flow burner regeneration type diesel particulate filter using SiC honeycomb

    SciTech Connect (OSTI)

    Okazoe, Hiroshi; Shimizu, Kenji; Watanabe, Yoshito; Santiago, E.; Kugland, P.; Ruth, W.

    1996-09-01T23:59:59.000Z

    A diesel particulate filter (DPF) for city buses was developed that combines a SiC filter and a full-now type burner for regeneration. Filter crack problems were averted by suppressing the peak temperature inside the filter to under 900 C. This was done by setting the maximum tolerable amount of collected particulate mass before regeneration at 50 g and controlling the burner so as to increase the regeneration gas temperature slowly up to a set value. This DPF was retrofitted to a Tokyo metropolitan bus to conduct a field test. The field test has been under way for half a year without any trouble or deterioration of system performance.

  16. Sweetspot: Near-infrared observations of 13 type Ia supernovae from a new NOAO survey probing the nearby smooth Hubble flow

    SciTech Connect (OSTI)

    Weyant, Anja; Wood-Vasey, W. Michael [Pittsburgh Particle physics, Astrophysics, and Cosmology Center (PITT PACC), Physics and Astronomy Department, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Allen, Lori; Joyce, Richard; Matheson, Thomas [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Garnavich, Peter M. [Department of Physics, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Jha, Saurabh W., E-mail: anw19@pitt.edu [Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States)

    2014-04-01T23:59:59.000Z

    We present 13 Type Ia supernovae (SNe Ia) observed in the rest-frame near-infrared (NIR) from 0.02 < z < 0.09 with the WIYN High-resolution Infrared Camera on the WIYN 3.5 m telescope. With only one to three points per light curve and a prior on the time of maximum from the spectrum used to type the object, we measure an H-band dispersion of spectroscopically normal SNe Ia of 0.164 mag. These observations continue to demonstrate the improved standard brightness of SNe Ia in an H band, even with limited data. Our sample includes two SNe Ia at z ? 0.09, which represent the most distant rest-frame NIR H-band observations published to date. This modest sample of 13 NIR SNe Ia represent the pilot sample for {sup S}weetSpot{sup —}a 3 yr NOAO Survey program that will observe 144 SNe Ia in the smooth Hubble flow. By the end of the survey we will have measured the relative distance to a redshift of z ? 0.05%-1%. Nearby Type Ia supernova (SN Ia) observations such as these will test the standard nature of SNe Ia in the rest-frame NIR, allow insight into the nature of dust, and provide a critical anchor for future cosmological SN Ia surveys at higher redshift.

  17. The linear and nonlinear stability of thread-annular flow

    E-Print Network [OSTI]

    Walton, Andrew G

    .walton@ic.ac.uk) The surgical technique of thread injection of medical implants is modelled by the axial pressure surgical trauma. The thread is stored on a spool and injected within a fluid by applying an axial pressure Navier­Stokes solution for sliding flow through an annulus (equation (1.1) below), they discovered

  18. Two-dimensional model of the air flow and temperature distribution in a cavity-type heat receiver of a solar stirling engine

    SciTech Connect (OSTI)

    Makhkamov, K.K.; Ingham, D.B.

    1999-11-01T23:59:59.000Z

    A theoretical study on the air flow and temperature in the heat receiver, affected by free convection, of a Stirling Engine for a Dish/Stirling Engine Power System is presented. The standard {kappa}-{epsilon} turbulence model for the fluid flow has been used and the boundary conditions employed were obtained using a second level mathematical model of the Stirling Engine working cycle. Physical models for the distribution of the solar insolation from the Concentrator on the bottom and side walls of the cavity-type heat receiver have been taken into account. The numerical results show that most of the heat losses in the receiver are due to re-radiation from the cavity and conduction through the walls of the cavity. It is in the region of the boundary of the input window of the heat receiver where there is a sensible reduction in the temperature in the shell of the heat exchangers and this is due to the free convection of the air. Further, the numerical results show that convective heat losses increase with decreasing tilt angle.

  19. The Shaft Torque of a Tandem Axial-Piston Pump

    E-Print Network [OSTI]

    Manring, Noah D.

    The Shaft Torque of a Tandem Axial- Piston Pump Noah D. Manring Viral S. Mehta Mechanical of this study is to identify the best indexed position of two rotating groups within a tandem axial-piston pump characteristics of the pump, other vibration aspects of the machine are also expected to be reduced. In particular

  20. Effects of inlet geometries on flow recirculation in an axial-flow pump

    E-Print Network [OSTI]

    Alpan, Kenan

    1984-01-01T23:59:59.000Z

    and mixing occurred. The problem was remedied for good by mounting two single lip seals back to back. Because of its availability, an automotive air conditioning con- denser was used as the heat exchanger for the cooling/lubricating system. The pressure... APPARATUS. 3. 1 Introduction. . . . ~ 3 ' 2 Test Pump 3. 3 Power Supply. 3. 4 Hydraulic Loop 3. 5 Lubricating and Cooling System. 3. 6 Inlet Geometries. ~ ~ ~ ~ ~ ~ ~ 3. 7 Instrumentation 'I P 14 14 14 19 23 23 30 33 CHAPTER IV. EXPERIMENTAL...

  1. Torsional Alfven Waves in Solar Magnetic Flux Tubes of Axial Symmetry

    E-Print Network [OSTI]

    Murawski, K; Musielak, Z E; Srivastava, A K; Kraskiewicz, J

    2015-01-01T23:59:59.000Z

    Aims: Propagation and energy transfer of torsional Alfv\\'en waves in solar magnetic flux tubes of axial symmetry is studied. Methods: An analytical model of a solar magnetic flux tube of axial symmetry is developed by specifying a magnetic flux and deriving general analytical formulae for the equilibrium mass density and a gas pressure. The main advantage of this model is that it can be easily adopted to any axisymmetric magnetic structure. The model is used to simulate numerically the propagation of nonlinear Alfv\\'en waves in such 2D flux tubes of axial symmetry embedded in the solar atmosphere. The waves are excited by a localized pulse in the azimuthal component of velocity and launched at the top of the solar photosphere, and they propagate through the solar chromosphere, transition region, and into the solar corona. Results: The results of our numerical simulations reveal a complex scenario of twisted magnetic field lines and flows associated with torsional Alfv\\'en waves as well as energy transfer to t...

  2. axial blanket experiments: Topics by E-print Network

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

    and ideas. We concentrate on the explanation and illustration of the key concept of bucket: its definition, formation and how it is used in generating the axial map. Keywords:...

  3. axial flux machine: Topics by E-print Network

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

    and ideas. We concentrate on the explanation and illustration of the key concept of bucket: its definition, formation and how it is used in generating the axial map. Keywords:...

  4. axial turbine cascade: Topics by E-print Network

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

    and ideas. We concentrate on the explanation and illustration of the key concept of bucket: its definition, formation and how it is used in generating the axial map. Keywords:...

  5. The axial behaviour of piled foundations in liquefiable soil

    E-Print Network [OSTI]

    Stringer, Mark

    2012-07-03T23:59:59.000Z

    Understanding the mechanisms by which any engineering structure resists load is an essential requirement for its consistent and reliable design. The axial resistance which can be mobilised by piled foundations in liquefiable soils when subjected...

  6. Applications of axial and radial compressor dynamic system modeling

    E-Print Network [OSTI]

    Spakovszky, Zoltán S. (Zoltán Sándor), 1972-

    2001-01-01T23:59:59.000Z

    The presented work is a compilation of four different projects related to axial and centrifugal compression systems. The projects are related by the underlying dynamic system modeling approach that is common in all of them. ...

  7. Optimization of the axial power shape in pressurized water reactors

    E-Print Network [OSTI]

    Melik, M. A.

    1981-01-01T23:59:59.000Z

    Analytical and numerical methods have been applied to find the optimum axial power profile in a PWR with respect to uranium utilization. The preferred shape was found to have a large central region of uniform power density, ...

  8. Axial clad strain behavior of sphere-pac fuel pins 

    E-Print Network [OSTI]

    Thomas, James Kelly

    1986-01-01T23:59:59.000Z

    quantitative di f f er ences exist. 17 CHAPTER III STEADY STATE MODELING Introduction This section descr ibes the analytic model developed to predict the axial shear load bearing capacity of a packed particle bed. The goal of this model development... par ticle beds. 36 CHAPTER IV VIBRATIONAL EXPERIMENTS Introduction The model developed in the previous chapter provides a method to predict the axial shear load bearing capacity of a packed particle bed under negligible vibr ation conditions...

  9. A wave refraction analysis for an axially symmetrical island

    E-Print Network [OSTI]

    Forst, Ronald John

    1966-01-01T23:59:59.000Z

    A WAVE REFRACTION ANALYSIS FOR AN AXIALLY SYMMETRICAL ISLAND A Thesis By LIEUTENANT RONALD J FORST UNITED STATES NAVY Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE l966 Major Subject Oceanography A WAVE REFRACTION ANALYSIS FOR AN AXIALLY SYMMETRICAL ISLAND A Thesis By LIEUTENANT RONALD J FORST UNITED STATES NAVY Approved as to style and content by; ( airma Committee) Head of Dep rtme t...

  10. Design of high temperature high speed electromagnetic axial thrust bearing

    E-Print Network [OSTI]

    Mohiuddin, Mohammad Waqar

    2002-01-01T23:59:59.000Z

    DESIGN OF HIGH TEMPERATURE HIGH SPEED ELECTROMAGNETIC AXIAL THRUST BEARING A Thesis by MOHAMMAD WAQAR MOHIUDDIN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 2002 Major Subject: Mechanical Engineering DESIGN OF HIGH TEMPERATURE HIGH SPEED ELECTROMAGNETIC AXIAL THRUST BEARING A Thesis by MOHAMMAD WAQAR MOHIUDDIN Submitted to Texas A&M University in partial fulfillment...

  11. Superfluid Phase Stability of 3 He in Axially Anisotropic Aerogel

    E-Print Network [OSTI]

    J. Pollanen; J. P. Davis; B. Reddy; K. R. Shirer; H. Choi

    Abstract. Measurements of superfluid 3 He in 98 % aerogel demonstrate the existence of a metastable A-like phase and a stable B-like phase. It has been suggested that the relative stability of these two phases is controlled by anisotropic quasiparticle scattering in the aerogel. Anisotropic scattering produced by axial compression of the aerogel has been predicted to stabilize the axial state of superfluid 3 He. To explore this possiblity, we used transverse acoustic impedance to map out the phase diagram of superfluid 3 He in a ? 98 % porous silica aerogel subjected to 17 % axial compression. We have previously shown that axial anisotropy in aerogel leads to optical birefringence and that optical cross-polarization studies can be used to characterize such anisotropy. Consequently, we have performed optical cross-polarization experiments to verify the presence and uniformity of the axial anisotropy in our aerogel sample. We find that uniform axial anisotropy introduced by 17 % compression does not stabilize the A-like phase. We also find an increase in the supercooling of the A-like phase at lower pressure, indicating a modification to B-like phase nucleation in globally anisotropic aerogels. 1.

  12. Design and market considerations for axial flux superconducting electric machine design

    E-Print Network [OSTI]

    Ainslie, Mark D; Shaw, Robert; Dawson, Lewis; Winfield, Andy; Steketee, Marina; Stockley, Simon

    2013-01-01T23:59:59.000Z

    In this paper, the authors investigate a number of design and market considerations for an axial flux superconducting electric machine design that uses high temperature superconductors. This work was carried out as part of the University of Cambridge's Centre for Entrepreneurial Learning ETECH Project programme, designed to accelerate entrepreneurship and diffusion of innovations based on early stage and potentially disruptive technologies from the University. The axial flux machine design is assumed to utilise high temperature superconductors in both wire (stator winding) and bulk (rotor field) forms, to operate over a temperature range of 65-77 K, and to have a power output in the range from 10s of kW up to 1 MW (typical for axial flux machines), with approximately 2-3 T as the peak trapped field in the bulk superconductors. The authors firstly investigate the applicability of this type of machine as a generator in small- and medium-sized wind turbines, including the current and forecasted market and pricin...

  13. Flow conditioner for fuel injector for combustor and method for low-NO.sub.x combustor

    DOE Patents [OSTI]

    Dutta, Partha; Smith, Kenneth O.; Ritz, Frank J.

    2013-09-10T23:59:59.000Z

    An injector for a gas turbine combustor including a catalyst coated surface forming a passage for feed gas flow and a channel for oxidant gas flow establishing an axial gas flow through a flow conditioner disposed at least partially within an inner wall of the injector. The flow conditioner includes a length with an interior passage opening into upstream and downstream ends for passage of the axial gas flow. An interior diameter of the interior passage smoothly reduces and then increases from upstream to downstream ends.

  14. Elbow mass flow meter

    DOE Patents [OSTI]

    McFarland, Andrew R. (College Station, TX); Rodgers, John C. (Santa Fe, NM); Ortiz, Carlos A. (Bryan, TX); Nelson, David C. (Santa Fe, NM)

    1994-01-01T23:59:59.000Z

    Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

  15. Impact of axial diffusion on nitric oxide exchange in the lungs

    E-Print Network [OSTI]

    George, Steven C.

    Impact of axial diffusion on nitric oxide exchange in the lungs HYE-WON SHIN1 AND STEVEN C. GEORGE1, Hye-Won, and Steven C. George. Impact of axial diffusion on nitric oxide exchange in the lungs. J Appl of the lungs, but neglects axial diffusion. We incorporated axial diffusion into a one-dimensional trumpet

  16. Analysis of rabbit intervertebral disc physiology based on water metabolism. II. Changes in normal intervertebral discs under axial vibratory load

    SciTech Connect (OSTI)

    Hirano, N.; Tsuji, H.; Ohshima, H.; Kitano, S.; Itoh, T.; Sano, A.

    1988-11-01T23:59:59.000Z

    Metabolic changes induced by axial vibratory load to the spine were investigated based on water metabolism in normal intervertebral discs of rabbits with or without pentobarbital anesthesia. Tritiated water concentration in the intervertebral discs of unanesthetized rabbits was reduced remarkably by axial vibration for 30 minutes using the vibration machine developed for this study. Repeated vibratory load for 18 and 42 hours duration showed the recovery of /sup 3/H/sub 2/O concentration of the intervertebral disc without anesthesia. Computer simulation suggested a reduction of blood flow surrounding the intervertebral disc following the vibration stress. However, no reduction of the /sup 3/H/sub 2/O concentration in the intervertebral disc was noted under anesthesia. Emotional stress cannot be excluded as a factor in water metabolism in the intervertebral disc.

  17. Axial Current Generation from Electric Field: Chiral Electric Separation Effect

    E-Print Network [OSTI]

    Xu-Guang Huang; Jinfeng Liao

    2013-06-07T23:59:59.000Z

    We study a relativistic plasma containing charged chiral fermions in an external electric field. We show that with the presence of both vector and axial charge densities, the electric field can induce an axial current along its direction and thus cause chirality separation. We call it the Chiral Electric Separation Effect (CESE). On very general basis, we argue that the strength of CESE is proportional to $\\mu_V\\mu_A$ with $\\mu_V$ and $\\mu_A$ the chemical potentials for vector charge and axial charge. We then explicitly calculate this CESE conductivity coefficient in thermal QED at leading-log order. The CESE can manifest a new gapless wave mode propagating along the electric field. Potential observable of CESE in heavy-ion collisions is also discussed.

  18. Axial Current Generation from Electric Field: Chiral Electric Separation Effect

    E-Print Network [OSTI]

    Huang, Xu-Guang

    2013-01-01T23:59:59.000Z

    We study a relativistic plasma containing charged chiral fermions in an external electric field. We show that with the presence of both vector and axial charge densities, the electric field can induce an axial current along its direction and thus cause chirality separation. We call it the Chiral Electric Separation Effect (CESE). On very general basis, we argue that the strength of CESE is proportional to $\\mu_V\\mu_A$ with $\\mu_V$ and $\\mu_A$ the chemical potentials for vector charge and axial charge. We then explicitly calculate this CESE conductivity coefficient in thermal QED at leading-log order. The CESE can manifest a new gapless wave mode propagating along the electric field. Potential observable of CESE in heavy-ion collisions is also discussed.

  19. Axial magnetic field and toroidally streaming fast ions in the dense plasma focus are natural consequences of conservation laws in the curved axisymmetric geometry of the current sheath

    E-Print Network [OSTI]

    Auluck, S K H

    2014-01-01T23:59:59.000Z

    Direct measurement of axial magnetic field in the PF-1000 dense plasma focus (DPF), and its reported correlation with neutron emission, call for a fresh look at previous reports of existence of axial magnetic field component in the DPF from other laboratories, and associated data suggesting toroidal directionality of fast ions participating in fusion reactions, with a view to understand the underlying physics. In this context, recent work dealing with application of the hyperbolic conservation law formalism to the DPF is extended in this paper to a curvilinear coordinate system, which reflects the shape of the DPF current sheath. Locally-unidirectional shock propagation in this coordinate system enables construction of a system of 7 one-dimensional hyperbolic conservation law equations with geometric source terms, taking into account all the components of magnetic field and flow velocity. Rankine-Hugoniot jump conditions for this system lead to expressions for the axial magnetic field and three components of ...

  20. Study of Laminar Flow Forced Convection Heat Transfer Behavior of a Phase Change Material Fluid

    E-Print Network [OSTI]

    Ravi, Gurunarayana

    2010-01-14T23:59:59.000Z

    with constant peripheral temperature and uniform axial and peripheral temperature, were considered in the case of circular tubes. An effective specific heat technique was used to model the phase change process assuming a hydrodynamically fully-developed flow...

  1. Neutrino Physics and Nuclear Axial Two-Body Interactions

    E-Print Network [OSTI]

    A. B. Balantekin; H. Yuksel

    2004-11-06T23:59:59.000Z

    We consider the counter-term describing isoscalar axial two-body currents in the nucleon-nucleon interaction, L1A, in the effective field theory approach. We determine this quantity using the solar neutrino data. We investigate the variation of L1A when different sets of data are used.

  2. Proceedings of the Axial Offset Anomaly (AOA) Science Workshop

    SciTech Connect (OSTI)

    None

    2003-06-01T23:59:59.000Z

    This report presents proceedings of the Axial Offset Anomaly (AOA) Science Workshop, held February 10-11 in Palo Alto, California. Twenty-two papers were presented on various aspects of AOA by utilities, EPRI Robust Fuel Program contractors, staff from EPRI and universities, international researchers, and equipment vendors.

  3. Collective quantization of axially symmetric gravitating B=2 skyrmion

    E-Print Network [OSTI]

    Hisayuki Sato; Nobuyuki Sawado; Noriko Shiiki

    2007-01-05T23:59:59.000Z

    In this paper we perform collective quantization of an axially symmetric skyrmion with baryon number two.The rotational and isorotational modes are quantized to obtain the static properties of a deuteron and other dibaryonic objects such as masses, charge densities, magnetic moments. We discuss how the gravity affects to those observables.

  4. The deep structure of Axial Volcano Michael West

    E-Print Network [OSTI]

    West, Michael

    the competing roles or ocean ridge and hot spot at Axial Volcano Provide a template on which long-term studies;Airgun survey April '99 20 gun array 8670 in3 volume 8 days #12;Airgun survey, April '99 5000+ shots 1225

  5. Operational benefits of relaxed axial power distribution control limits

    SciTech Connect (OSTI)

    Kitlan, M.S. Jr.; Miller, R.W.

    1987-01-01T23:59:59.000Z

    Constant axial offset control (CAOC) was developed in the early 1970s in response to lower loss-of-coolant accident-based peaking factor limits. Th CAOC requires control of the axial power distribution within a specified band, typically +/- 5% or +3, -12% axial flux difference (AFD), about a measured target value of AFD. Operational outside of the CAOC limits results in the accumulation of penalty time. One hour of penalty time in any 24-h period is permitted. Although CAOC is sufficient to ensure peaking factor limits are satisfied, operation outside of CAOC limits is beneficial under certain conditions. Allowing a relaxation in CAOC restrictions can be used both to enhance the load follow capability of the plant by allowing control strategies that minimize the boron system duty or increase the return to power capability and to greatly increase the ability to return to power after a plant trip or shutdown. To achieve these benefits, relaxed axial offset control (RAOC) was developed. Other benefits of RAOC include a simplified technical specification and the ability to perform in-core/ex-core calibrations at higher powers. Duke Power Company has benefited in many of these ways by changing from CAOC power distribution limits to RAOC power distribution limits at the McGuire Nuclear Station. One of the chief benefits has been the ability to achieve full power much more quickly following shutdowns of short duration and reactor trips during the last half of the cycle lifetime.

  6. ELECTROMECHANICAL RELIABILITY TESTING OF THREE-AXIAL SILICON FORCE SENSORS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , available automatic test equipment for integrated circuits (ICs) can be leveraged [2]. The reliabilityELECTROMECHANICAL RELIABILITY TESTING OF THREE-AXIAL SILICON FORCE SENSORS S. Spinner1,2, J the measurement results. 1. INTRODUCTION The reliability of microelectromechanical systems (MEMS) receives growing

  7. axial fuel optimization: Topics by E-print Network

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

    axial fuel optimization First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Trajectory optimization for...

  8. Axial force imparted by a current-free magnetically expanding plasma

    SciTech Connect (OSTI)

    Takahashi, Kazunori [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Department of Electrical Engineering and Computer Science, Iwate University, Morioka 020-8551 (Japan); Lafleur, Trevor; Charles, Christine; Alexander, Peter; Boswell, Rod W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia)

    2012-08-15T23:59:59.000Z

    The axial force imparted from a magnetically expanding, current-free, radiofrequency plasma is directly measured. For an argon gas flow rate of 25 sccm and an effective rf input power of {approx}800W, a maximum force of {approx}6mN is obtained; {approx}3mN of which is transmitted via the expanding magnetic field. The measured forces are reasonably compared with a simple fluid model associated with the measured electron pressure. The model suggests that the total force is the sum of an electron pressure inside the source and a Lorentz force due to the electron diamagnetic drift current and the applied radial magnetic field. It is shown that the Lorentz force is greatest near the magnetic nozzle surface where the radial pressure gradient is largest.

  9. A TURBINE RESEARCH FACILITY TO STUDY TIP DESENSITIZATION INCLUDING COOLING FLOWS

    E-Print Network [OSTI]

    Camci, Cengiz

    CC-1 A TURBINE RESEARCH FACILITY TO STUDY TIP DESENSITIZATION INCLUDING COOLING FLOWS Cengiz Camci with the description of the Axial Flow Turbine Research Facility (AFTRF) installed at the Turbomachinery Laboratory of the Pennsylvania State University. The AFTRF is a single-stage cold flow turbine specifically designed for studying

  10. Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow

    E-Print Network [OSTI]

    Boyer, Edmond

    Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S modeling of the turbulent flow in a rotor-stator cavity subjected to a superimposed throughflow with heat the dynamical effects from the heat transfer process. The fluid flow in an enclosed disk system with axial

  11. Determing Degradation Of Fiberboard In The 9975 Shipping Package By Measuring Axial Gap

    SciTech Connect (OSTI)

    Hackney, E. R.; Dougherty, W. L.; Dunn, K. A.; Stefek, T. M

    2013-08-01T23:59:59.000Z

    Currently, thousands of model 9975 transportation packages are in use by the US Department of Energy (DOE); the design of which has been certified by DOE for shipment of Type B radioactive and fissile materials in accordance with Part 71, Title 10 Code of Federal Regulations (CFR), or 10 CFR 71, Packaging and Transportation of Radioactive Material. These transportation packages are also approved for the storage of DOE-STD-3013 containers at the Savannah River Site (SRS). As such, the 9975 has been continuously exposed to the service environment for a period of time greater than the approved transportation service life. In order to ensure the material integrity as specified in the safety basis, an extensive surveillance program is in place in K-Area Complex (KAC) to monitor the structural and thermal properties of the fiberboard of the 9975 shipping packages. The surveillance approach uses a combination of Non-Destructive Examination (NDE) field surveillance and Destructive Examination (DE) lab testing to validate the 9975 performance assumptions. The fiberboard in the 9975 is credited with thermal insulation, criticality control and resistance to crushing. During surveillance monitoring in KAC, an increased axial gap of the fiberboard was discovered on selected items packaged at Rocky Flats Environmental Technology Site (RFETS). Many of these packages were later found to contain excess moisture. Savannah River National Laboratory (SRNL) testing has resulted in a better understanding of the relationship between the fiberboard moisture level and compaction of the fiberboard under storage conditions and during transport. In laboratory testing, the higher moisture content has been shown to correspond to higher total compaction of fiberboard material and compaction rate. The fiberboard height is reduced by compression of the layers. This change is observed directly in the axial gap between the flange and the air shield. The axial gap measurement is made during the pre-use inspection or during the annual recertification process and is a screening measurement for changes in the fiberboard.

  12. Molecular-Level Study of the Effect of Prior Axial Compression/Torsion on the Axial-Tensile Strength

    E-Print Network [OSTI]

    Grujicic, Mica

    that prior axial torsion can induce major changes in the material microstructure, causing significant, such as bullets, detonated-mine-induced soil ejecta, improvised explosive devices (IEDs), shell or turbine frag of high-fidelity material-constitutive models capa- ble of describing the behavior of fibers

  13. Plate Fin Heat Exchanger Model with Axial Conduction and Variable Properties

    SciTech Connect (OSTI)

    Hansen, B.J.; White, M.J.; Klebaner, A.; /Fermilab

    2011-06-10T23:59:59.000Z

    Future superconducting radio frequency (SRF) cavities, as part of Project X at Fermilab, will be cooled to superfluid helium temperatures by a cryogenic distribution system supplying cold supercritical helium. To reduce vapor fraction during the final Joule-Thomson (J-T) expansion into the superfluid helium cooling bath, counter-flow, plate-fin heat exchangers will be utilized. Due to their compact size and ease of fabrication, plate-fin heat exchangers are an effective option. However, the design of compact and high-effectiveness cryogenic heat exchangers operating at liquid helium temperatures requires consideration of axial heat conduction along the direction of flow, in addition to variable fluid properties. Here we present a numerical model that includes the effects of axial conduction and variable properties for a plate fin heat exchanger. The model is used to guide design decisions on heat exchanger material choice and geometry. In addition, the J-T expansion process is modeled with the heat exchanger to analyze the effect of heat load and cryogenic supply parameters. A numerical model that includes the effects of axial conduction and variable properties for a plate fin heat exchanger was developed and the effect of various design parameters on overall heat exchanger size was investigated. It was found that highly conductive metals should be avoided in the design of compact JT heat exchangers. For the geometry considered, the optimal conductivity is around 3.5 W/m-K and can range from 0.3-10 W/m-K without a large loss in performance. The model was implemented with an isenthalpic expansion process. Increasing the cold side inlet temperature from 2K to 2.2 K decreased the liquid fraction from 0.856 to 0.839 which corresponds to a 0.12 g/s increase in supercritical helium supply needed to maintain liquid level in the cooling bath. Lastly, it was found that the effectiveness increased when the heat load was below the design value. Therefore, the heat exchanger should be sized on the high end of the required heat load.

  14. Modeling of FRP-jacketed RC columns subject to combined axial and lateral loads

    E-Print Network [OSTI]

    Lee, Chung-Sheng

    2006-01-01T23:59:59.000Z

    LOCATIONS #6 u-bars @ 4" 3" PVC for axial load and verticalsteel Steel jacket encasing load stub 2" PVC for clevisattatch 3" PVC for axial load A B Vertical tiedown Column

  15. European Fusion Theory Conference Non-local features of transport in the axial tokamak region

    E-Print Network [OSTI]

    9th European Fusion Theory Conference Non-local features of transport in the axial tokamak region J effects in the axial region of an axi- symmetric tokamak equilibrium. The starting point is the guiding

  16. A Comparative Study of Modular Axial Flux Podded Generators for Marine Current Turbines

    E-Print Network [OSTI]

    Brest, Université de

    A Comparative Study of Modular Axial Flux Podded Generators for Marine Current Turbines Sofiane turbines (MCTs). Due to the submarine environment, maintenance operations are very hard, very costly current turbine, axial flux permanent magnet generator, design, optimization. Nomenclature MCT = Marine

  17. Technological cost%3CU%2B2010%3Ereduction pathways for axial%3CU%2B2010%3Eflow turbines in the marine hydrokinetic environment.

    SciTech Connect (OSTI)

    Laird, Daniel L.; Johnson, Erick L.; Ochs, Margaret Ellen; Boren, Blake [Oregon State University, Corvallis, OR

    2013-05-01T23:59:59.000Z

    This report considers and prioritizes potential technical costreduction pathways for axialflow turbines designed for tidal, river, and ocean current resources. This report focuses on technical research and development costreduction pathways related to the device technology rather than environmental monitoring or permitting opportunities. Three sources of information were utilized to understand current cost drivers and develop a list of potential costreduction pathways: a literature review of technical work related to axialflow turbines, the U.S. Department of Energy Reference Model effort, and informal webinars and other targeted interactions with industry developers. Data from these various information sources were aggregated and prioritized with respect to potential impact on the lifetime levelized cost of energy. The four most promising costreduction pathways include structural design optimization; improved deployment, maintenance, and recovery; system simplicity and reliability; and array optimization.

  18. The influence of current collectors on Tayler instability and electro-vortex flows in liquid metal batteries

    E-Print Network [OSTI]

    Weber, N; Priede, J; Stefani, F; Weier, T

    2014-01-01T23:59:59.000Z

    The Tayler instability is a kink-type flow instability which occurs when the electrical current through a conducting fluid exceeds a certain critical value. Originally studied in the astrophysical context, the instability was recently shown to be also a limiting factor for the upward scalability of liquid metal batteries. In this paper, we continue our efforts to simulate this instability for liquid metals within the framework of an integro-differential equation approach. The original solver is enhanced by multi-domain support with Dirichlet-Neumann partitioning for the static boundaries. Particular focus is laid on the detailed influence of the axial electrical boundary conditions on the characteristic features of the Tayler instability, and, secondly, on the occurrence of electro-vortex flows and their relevance for liquid metal batteries.

  19. Correction to "Threedimensional computational axial tomography scan of a volcano with cosmic ray muon radiography"

    E-Print Network [OSTI]

    Aoki, Yosuke

    Correction to "Threedimensional computational axial tomography scan of a volcano with cosmic ray.1029/2011JB008256. [1] In the paper "Threedimensional computational axial tomography scan of a volcano. Aoki, R. Nishiyama, D. Shoji, and H. Tsuiji (2011), Correction to "Threedimensional computational axial

  20. AXIAL-FIELD SYNCHRONOUS MACHINE WITH HOMOPOLAR FLUX IN THE AIRGAP FOR A FLYWHEEL ACCUMULATOR

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    AXIAL-FIELD SYNCHRONOUS MACHINE WITH HOMOPOLAR FLUX IN THE AIRGAP FOR A FLYWHEEL ACCUMULATOR@bretagne.ens-cachan.fr Abstract: A new axial-field synchronous machine designed for a flywheel accumulator is presented herein with experimental results. Keywords: flywheel accumulator, axial-field synchronous machine, double-face printed

  1. Flow Field Results of the Cambridge Stratified Swirl Burner Using Laser Doppler Anemometer

    E-Print Network [OSTI]

    Zhou, Ruigang; Sweeney, Mark; Hochgreb, Simone

    2012-06-08T23:59:59.000Z

    : outer annulus axial flow plenum; C: outer annulus swirl flow plenum; D: locating collar; E: outer tube; F: middle tube; G: inner tube; H: flow straighteners; I: swirl generating collar; J: ceramic cap; K: wire mesh; L: honeycomb section; M: perforated... the upper plenum joins the outer annulus through a swirl collar {I}, via a radially symmetric pattern of inlets angled at 30? to the annulus and at 30? to the horizontal. These angled jets induce a tangential component to the axial flow from the middle...

  2. Axially staged combustion system for a gas turbine engine

    DOE Patents [OSTI]

    Bland, Robert J. (Oviedo, FL)

    2009-12-15T23:59:59.000Z

    An axially staged combustion system is provided for a gas turbine engine comprising a main body structure having a plurality of first and second injectors. First structure provides fuel to at least one of the first injectors. The fuel provided to the one first injector is adapted to mix with air and ignite to produce a flame such that the flame associated with the one first injector defines a flame front having an average length when measured from a reference surface of the main body structure. Each of the second injectors comprising a section extending from the reference surface of the main body structure through the flame front and having a length greater than the average length of the flame front. Second structure provides fuel to at least one of the second injectors. The fuel passes through the one second injector and exits the one second injector at a location axially spaced from the flame front.

  3. Axial SiGe Heteronanowire Tunneling Field-Effect Transistors

    SciTech Connect (OSTI)

    Le, Son T.; Jannaty, P.; Luo, Xu; Zaslavsky, A.; Perea, Daniel E.; Dayeh, Shadi A.; Picraux, Samuel T.

    2012-10-31T23:59:59.000Z

    We present silicon-compatible tri-gated p-Ge/i-Si/n-Si axial heteronanowire tunneling field-effect transistors (TFETs), where on-state tunneling occurs in the Ge drain section, while off-state leakage is dominated by the Si junction in the source. Our TFETs have high ION ~ 2 µA/µm, fully suppressed ambipolarity, and a sub-threshold slope SS ~ 140 mV/decade over 4 decades of current with lowest SS ~ 50 mV/decade. Device operation in the tunneling mode is confirmed by three-dimensional TCAD simulation. Interestingly, in addition to the TFET mode, our devices work as standard nanowire FETs with good ION/IOFF ratio when the source-drain junction is forward-biased. The improved transport in both biasing modes confirms the benefits of utilizing bandgap engineered axial nanowires for enhancing device performance.

  4. Measurement of axial injection displacement with trim coil current unbalance

    SciTech Connect (OSTI)

    Covo, Michel Kireeff, E-mail: mkireeffcovo@lbl.gov [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States)

    2014-08-15T23:59:59.000Z

    The Dee probe used for measuring internal radial beam intensity shows large losses inside the radius of 20 cm of the 88 in. cyclotron. The current of the top and bottom innermost trim coil 1 is unbalanced to study effects of the axial injection displacement. A beam profile monitor images the ion beam bunches, turn by turn. The experimental bunch center of mass position is compared with calculations of the magnetic mirror effect displacement and shows good agreement.

  5. Coral Extension Rate Analysis Using Computed Axial Tomography

    E-Print Network [OSTI]

    Yudelman, Eleanor Ann

    2014-01-10T23:59:59.000Z

    CORAL EXTENSION RATE ANALYSIS USING COMPUTED AXIAL TOMOGRAPHY A Thesis by ELEANOR ANN YUDELMAN Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE Chair of Committee, Niall Slowey Committee Members, Deborah Thomas Benjamin Giese George P. Schmahl Head of Department, Deborah Thomas May 2014 Major Subject: Oceanography Copyright 2014 Eleanor Ann Yudelman ii ABSTRACT...

  6. Enhanced betatron X-rays from axially modulated plasma wakefields

    E-Print Network [OSTI]

    Palastro, J P; Gordon, D

    2015-01-01T23:59:59.000Z

    In the cavitation regime of plasma-based accelerators, a population of high-energy electrons tailing the driver can undergo betatron motion. The motion results in X-ray emission, but the brilliance and photon energy are limited by the electrons' initial transverse coordinate. To overcome this, we exploit parametrically unstable betatron motion in a cavitated, axially modulated plasma. Theory and simulations are presented showing that the unstable oscillations increase both the total X-ray energy and average photon energy.

  7. Nuclear reactor control rod with uniformly changeable axial worth

    SciTech Connect (OSTI)

    Freeman, T.R.

    1987-11-17T23:59:59.000Z

    In combination with a fuel assembly having at least one hollow guide thimble, means to compensate for a reduction in reactivity occurring generally uniformly in a transverse direction and symmetric in the axial direction is described, comprising: (a) a control rod inserted in the guide thimble including (i) an elongated inner cylindrical member having a lower end, (ii) an elongated outer cylindrical member surrounding the inner member and having a lower end with concentrically-arranged lower inner and outer edge portions defined thereon, (iii) each of the members being composed of alternating poison and nonpoison regions, (iv) the inner member being axially movable relative to the outer member, (v) an outwardly projecting ledge adapted to support in a rest relationship the lower end of the outer member; and (b) means for retaining the outer member in a stationary position in the guide thimble while the inner member is movable axially relative thereto to adjust the degree to which the poison regions of the members overlap with the nonpoison regions and thereby change the overall worth of the rod. (c) The retaining means are in a lower portion of the guide thimble and sized to support the lower end of the outer member at its lower outer edge portion. The retaining means have a central hole sized to allow passage of the lower end and ledge of the inner member therethrough.

  8. Axial-vector coupling constants and chiral-symmetry restoration

    SciTech Connect (OSTI)

    Henley, E.M. (Department of Physics FM-15 and Institute for Nuclear Theory HN-12, University of Washington, Seattle, Washington 98195 (United States)); Hwang, W.P. (Department of Physics, National Taiwan University, Taipei, Taiwan 10764 (Taiwan, Province of China)); Kisslinger, L.S. (Department of Physics, Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213 (United States))

    1992-07-01T23:59:59.000Z

    The isovector axial-vector coupling constant {ital g}{sub {ital A}} is determined by using the method of QCD sum rules. A sum rule for ({ital g}{sub {ital A}}{minus}1) is obtained, and it is shown that, with standard values of the quark condensates, {ital g}{sub {ital A}}=1.26{plus minus}0.08. It is also shown that the isovector axial-vector coupling ({ital g}{sub {ital A}}{minus}1)=0 in the limit in which chiral symmetry is restored, and the quark condensate vanishes. A sum rule is also obtained for the isoscalar'' axial-vector coupling constant {ital g}{sub {ital A}}{sup {ital S}}, which is found to be 0.13 if the isovector values of susceptibilities are used. On the other hand, {ital g}{sub {ital A}}{sup {ital S}}={minus}0.68 if the quark condensate is set to zero while {ital g}{sub {ital A}}{sup {ital S}}={minus}1.00 if both the quark and gluon condensates vanish in the event of chiral-symmetry restoration. The values of {ital g}{sub {ital A}} and {ital g}{sub {ital A}}{sup {ital S}} allow us to deduce {Delta}{ital u} and {Delta}{ital d} in the proton.

  9. Convective cores in galactic cooling flows

    E-Print Network [OSTI]

    A. Kritsuk; T. Plewa; E. Mueller

    2001-05-02T23:59:59.000Z

    We use hydrodynamic simulations with adaptive grid refinement to study the dependence of hot gas flows in X-ray luminous giant elliptical galaxies on the efficiency of heat supply to the gas. We consider a number of potential heating mechanisms including Type Ia supernovae and sporadic nuclear activity of a central supermassive black hole. As a starting point for this research we use an equilibrium hydrostatic recycling model (Kritsuk 1996). We show that a compact cooling inflow develops, if the heating is slightly insufficient to counterbalance radiative cooling of the hot gas in the central few kiloparsecs. An excessive heating in the centre, instead, drives a convectively unstable outflow. We model the onset of the instability and a quasi-steady convective regime in the core of the galaxy in two-dimensions assuming axial symmetry. Provided the power of net energy supply in the core is not too high, the convection remains subsonic. The convective pattern is dominated by buoyancy driven large-scale mushroom-like structures. Unlike in the case of a cooling inflow, the X-ray surface brightness of an (on average) isentropic convective core does not display a sharp maximum at the centre. A hybrid model, which combines a subsonic peripheral cooling inflow with an inner convective core, appears to be stable. We also discuss observational implications of these results.

  10. Exploring multi-layer flow network of international trade based on flow distances

    E-Print Network [OSTI]

    Shen, Bin; Zheng, Qiuhua

    2015-01-01T23:59:59.000Z

    Based on the approach of flow distances, the international trade flow system is studied from the perspective of multi-layer flow network. A model of multi-layer flow network is proposed for modelling and analyzing multiple types of flows in flow systems. Then, flow distances are introduced, and symmetric minimum flow distance is presented. Subsequently, we discuss the establishment of the multi-layer flow networks of international trade from two coupled viewpoints, i.e., the viewpoint of commodity flow and that of money flow. Thus, the multi-layer flow networks of international trade is explored. First, trading "trophic levels" are adopted to depict positions that economies occupied in the flow network. We find that the distributions of trading "trophic levels" have the similar clustering pattern for different types of commodity, and there are some regularities between money flow network and commodity flow network. Second, we find that active and competitive countries trade a wide spectrum of products, while ...

  11. Flow characteristics in underground coal gasification

    SciTech Connect (OSTI)

    Chang, H.L.; Himmelblau, D.M.; Edgar, T.F.

    1982-01-01T23:59:59.000Z

    During the Hoe Creek No. 2 (Wyoming) underground-coal-gasification field test, researchers introduced helium pulses to characterize the flow field and to estimate the coefficients in dispersion models of the flow. Flow models such as the axial-dispersion and parallel tanks-in-series models allowed interpretation of the in situ combustion flow field from the residence time distribution of the tracer gas. A quantitative analysis of the Hoe Creek tracer response curves revealed an increasing departure from a plug-flow regime with time, which was due to the combined effects of the free and forced convection in addition to the complex nonuniformity of the flow field. The Peclet number was a function of temperature, pressure, gas recovery, and characteristic velocity, as well as the split of the gas between the parallel streams in the model.

  12. Microscopic derivation of nuclear rotation-vibration model, axially symmetric case

    E-Print Network [OSTI]

    Gulshani, Parviz

    2015-01-01T23:59:59.000Z

    We derive from first principles the successful phenomenological hydrodynamic model of Bohr-Davydov-Faessler-Greiner for rotation-vibration motion of an axially symmetric deformed nucleus. The derivation is not limited to small oscillation amplitude, and provides microscopic expressions for the interaction operators among the rotation, vibration, and intrinsic motions, for the moment of inertia, vibration mass, and for the deformation variables. The method uses canonical transformations to collective co-ordinates, followed by a constrained variational method, with the associated constraints imposed on the wavefunction rather than on the particle co-ordinates. The approach yields three self-consistent, time-reversal invariant, cranking-type Schrodinger equations for the rotation-vibration and intrinsic motions, and a self-consistency equation. For deformed harmonic oscillator mean-field potentials, these equations are solved in closed forms for the energies, moments of inertia, quadrupole moments and transition...

  13. Anomalous junctions characterized by Raman spectroscopy in Si{sub x}Ge{sub 1?x} nanowires with axially degraded components

    SciTech Connect (OSTI)

    Xia, Minggang, E-mail: xiamg@mail.xjtu.edu.cn [Laboratory of Nanostructure and Physics Properties, and MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi'an Jiaotong University, 710049 (China); Department of Optical Information Science and Technology, School of Science, Xi'an Jiaotong University, 710049 (China); Han, Jinyun; Cheng, Zhaofang; Liang, Chunping; Zhang, Shengli [Laboratory of Nanostructure and Physics Properties, and MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi'an Jiaotong University, 710049 (China); Department of Applied Physics, School of Science, Xi'an Jiaotong University, Shaanxi 710049 (China)

    2014-09-08T23:59:59.000Z

    The characterization of junctions in nanowires by high-resolution transmission electron microscopy with spherical aberration correction is tricky and tedious. Many disadvantages also exist, including rigorous sample preparation and structural damage inflicted by high-energy electrons. In this work, we present a simple, low-cost, and non-destructive Raman spectroscopy method of characterizing anomalous junctions in nanowires with axially degraded components. The Raman spectra of Si{sub x}Ge{sub 1?x} nanowires with axially degraded components are studied in detail using a confocal micro-Raman spectrometer. Three Raman peaks (?{sub Si–Si}?=?490?cm{sup ?1}, ?{sub Si–Ge}?=?400?cm{sup ?1}, and ?{sub Ge–Ge}?=?284?cm{sup ?1}) up-shift with increased Si content. This up-shift originates in the bond compression induced by a confined effect on the radial direction of nanowire. The anomalous junctions in Si{sub x}Ge{sub 1?x} nanowires with axially degraded components are then observed by Raman spectroscopy and verified by transmission electron microscopy energy-dispersive X-ray spectroscopy. The anomalous junctions of Si{sub x}Ge{sub 1?x} nanowires with axially degraded components are due to the vortex flow of inlet SiH{sub 4} and GeH{sub 4} gas in their synthesis. The anomalous junctions can be used as raw materials for fabricating devices with special functions.

  14. Tri-axial magnetic anisotropies in RE{sub 2}Ba{sub 4}Cu{sub 7}O{sub 15?y} superconductors

    SciTech Connect (OSTI)

    Horii, Shigeru, E-mail: horii.shigeru.7e@kyoto-u.ac.jp; Doi, Toshiya [Graduate School of Energy Science, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan); Okuhira, Shota; Yamaki, Momoko [Department of Environmental Systems Engineering, Kochi University of Technology, Tosa-Yamada, Kami-shi, Kochi 782-8502 (Japan); Kishio, Kohji; Shimoyama, Jun-ichi [Department of Applied Chemistry, University of Tokyo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2014-03-21T23:59:59.000Z

    We report a novel quantification method of tri-axial magnetic anisotropy in orthorhombic substances containing rare earth (RE) ions using tri-axial magnetic alignment and tri-axial magnetic anisotropies depending on the type of RE in RE-based cuprate superconductors. From the changes in the axes for magnetization in magnetically aligned powders of (RE?{sub 1?x}RE?{sub x}){sub 2}Ba{sub 4}Cu{sub 7}O{sub y} [(RE?,RE?)247] containing RE ions with different single-ion magnetic anisotropies, the ratios of three-dimensional magnetic anisotropies between RE?247 and RE?247 could be determined. The results in (Y,Er)247, (Dy,Er)247, (Ho,Er)247, and (Y,Eu)247 systems suggest that magnetic anisotropies largely depended on the type of RE? (or RE?), even in the heavy RE ions with higher magnetic anisotropies. An appropriate choice of RE ions in RE-based cuprate superconductors enables the reduction of the required magnetic field for the production of their bulks and thick films based on the tri-axial magnetic alignment technique using modulated rotation magnetic fields.

  15. axial-gap type synchronous: Topics by E-print Network

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

    CB2 1PZ, U.K. (e-mail: szj10@mails. tsinghua.edu.cn). M. D. Ainslie, A. M. Campbell, and D. A. Cardwell are with the Bulk Su- perconductivity Group... Shen, Zejun; Ainslie, Mark...

  16. axial-flow turbojet engine: Topics by E-print Network

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

    Engineering Business Minor for Engineering Students Civil Infrastructure Computer Science Electrical & Computer Engineering Engineering Physics Environmental Engineering...

  17. axial flow multi-stage: Topics by E-print Network

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

    Iris Segmentation Framework. In A. Campilho and M. Kamel, editors, Proceedings of the 9th International Conference on Image Analysis and Recognition (ICIAR'12), volume Computer...

  18. axial-flow helium gas: Topics by E-print Network

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

    per atom (dpa) and helium production levels as a function of position within the high flux regions of a recent conceptual model for the "next-step" fusion device DEMO....

  19. Design, build and test of an axial flow hydrokinetic turbine with fatigue analysis

    E-Print Network [OSTI]

    Ketcham, Jerod W

    2010-01-01T23:59:59.000Z

    OpenProp is an open source propeller and turbine design and analysis code that has been in development since 2007 by MIT graduate students under the supervision of Professor Richard Kimball. In order to test the performance ...

  20. axial-flow gas turbine-propeller: Topics by E-print Network

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

    of a blade to it's back is 1 1316 inches. The blade diameter is 6 inches and the bucket height is 1 inch. 'Ihe rotor is press-fit onto a shaft and a balancing top is added......

  1. axial-flow hydraulic turbines: Topics by E-print Network

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

    per year (Anderson et al. 1999). This metric has 83 WIND TURBINE SITING IN AN URBAN ENVIRONMENT: THE HULL, MA 660 KW TURBINE Renewable Energy Websites Summary: 1 WIND TURBINE...

  2. Combustion in a Transonic Flow with Large Axial and Transverse Pressure Gradients

    E-Print Network [OSTI]

    Liu, Feng

    in turbine passages of a gas turbine engine presents exciting new challenges and opportunities. Combustion in the stators and perhaps eventually in the rotors of the gas turbine engine is a new proposed strategy that can of turbojet and turbofan engines as well as ground-based gas turbine engines through the use of augmented

  3. Estimation of axial compressor body forces using three-dimensional flow computations

    E-Print Network [OSTI]

    Reichstein, Georg A

    2009-01-01T23:59:59.000Z

    This thesis presents an examination of body force distributions in a single stage low speed compressor. The body force distributions are developed using two different computational procedures, an axisymmetric streamline ...

  4. axial-flow ventricular assist: Topics by E-print Network

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

    pattern, although some minor discrepancies were observed in the morphology of the 12-lead electrocardiogram. Keywords: Bidomain theory, hybrid model, anisotropy, ventricles,...

  5. Effects of Large Energetic Vortices on Axial-Flow Hydrokinetic Turbines

    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 for4,645 3,625govInstrumentstdmadapInactiveVisitingContract ManagementDiscoveringESnetEffective safety ...

  6. Axial Ge/Si nanowire heterostructure tunnel FETs.

    SciTech Connect (OSTI)

    Dayeh, Shadi A. (Los Alamos National Laboratory); Gin, Aaron V.; Huang, Jian Yu; Picraux, Samuel Thomas (Los Alamos National Laboratory)

    2010-03-01T23:59:59.000Z

    Axial Ge/Si heterostructure nanowires (NWs) allow energy band-edge engineering along the axis of the NW, which is the charge transport direction, and the realization of asymmetric devices for novel device architectures. This work reports on two significant advances in the area of heterostructure NWs and tunnel FETs: (i) the realization of 100% compositionally modulated Si/Ge axial heterostructure NWs with lengths suitable for device fabrication and (ii) the design and implementation of Schottky barrier tunnel FETs on these NWs for high-on currents and suppressed ambipolar behavior. Initial prototype devices with 10 nm PECVD SiN{sub x} gate dielectric resulted in a very high current drive in excess of 100 {micro}A/{micro}m (I/{pi}D) and 10{sup 5} I{sub on}/I{sub off} ratios. Prior work on the synthesis of Ge/Si axial NW heterostructures through the VLS mechanism have resulted in axial Si/Si{sub 1-x}Ge{sub x} NW heterostructures with x{sub max} {approx} 0.3, and more recently 100% composition modulation was achieved with a solid growth catalyst. In this latter case, the thickness of the heterostructure cannot exceed few atomic layers due to the slow axial growth rate and concurrent radial deposition on the NW sidewalls leading to a mixture of axial and radial deposition, which imposes a big challenge for fabricating useful devices form these NWs in the near future. Here, we report the VLS growth of 100% doping and composition modulated axial Ge/Si heterostructure NWs with lengths appropriate for device fabrication by devising a growth procedure that eliminates Au diffusion on the NW sidewalls and minimizes random kinking in the heterostructure NWs as deduced from detailed microscopy analysis. Fig. 1 a shows a cross-sectional SEM image of epitaxial Ge/Si axial NW heterostructures grown on a Ge(111) surface. The interface abruptness in these Ge/Si heterostructure NWs is of the order of the NW diameter. Some of these NWs develop a crystallographic kink that is {approx}20{sup o} off the <111> axis at about 300 nm away from the Ge/Si interface. This provides a natural marker for placing the gate contact electrodes and gate metal at appropriate location for desired high-on current and reduced ambipolarity as shown in Fig. 2. The 1D heterostructures allow band-edge engineering in the transport direction, not easily accessible in planar devices, providing an additional degree of freedom for designing tunnel FETs (TFETs). For instance, a Ge tunnel source can be used for efficient electron/hole tunneling and a Si drain can be used for reduced back-tunneling and ambipolar behavior. Interface abruptness on the other hand (particularly for doping) imposes challenges in these structures and others for realizing high performance TFETs in p-i-n junctions. Since the metal-semiconductor contacts provide a sharp interface with band-edge control, we use properly designed Schottky contacts (aided by 3D Silvaco simulations) as the tunnel barriers both at the source and drain and utilize the asymmetry in the Ge/Si channel bandgap to reduce ambipolar transport behavior generally observed in TFETs. Fig. 3 shows the room-temperature transfer curves of a Ge/Si heterostructure TFET (H-TFET) for different V{sub DS} values showing a maximum on-current of {approx}7 {micro}A, {approx}170 mV/decade inverse subthreshold slope and 5 orders of magnitude I{sub on}/I{sub off} ratios for all V{sub DS} biases considered here. This high on-current value is {approx}1750 X higher than that obtained with Si p-i-n{sup +} NW TFETs and {approx}35 X higher than that obtained with CNT TFET. The I{sub on}/I{sub off} ratio and inverse subthreshold slope compare favorably to that of Si {approx} 10{sup 3} I{sub on}/I{sub off} and {approx} 800 mV/decade SS{sup -1} but lags behind those of CNT TFET due to poor PECVD nitride gate oxide quality ({var_epsilon}{sub r} {approx} 3-4). The asymmetry in the Schottky barrier heights used here eliminates the stringent requirements of abrupt doped interfaces used in p-i-n based TFETs, which is hard to achieve both in thin-film and

  7. Electrostatic waves in carbon nanotubes with an axial magnetic field

    SciTech Connect (OSTI)

    Abdikian, Alireza [Department of Physics, Malayer University, Malayer 65719-95863 (Iran, Islamic Republic of)] [Department of Physics, Malayer University, Malayer 65719-95863 (Iran, Islamic Republic of); Bagheri, Mehran [Laser and Plasma Research Institute, Shahid Beheshti University, G. C., Evin, Tehran 19835-63113 (Iran, Islamic Republic of)] [Laser and Plasma Research Institute, Shahid Beheshti University, G. C., Evin, Tehran 19835-63113 (Iran, Islamic Republic of)

    2013-10-15T23:59:59.000Z

    Based on a linearized hydrodynamic model and within the quasi-static approximation, the dispersion relation of electrostatic waves propagating through single-walled carbon nanotubes subject to an axial magnetic field is theoretically explored. In the classical limit, we obtain two main possible waves which in turn are divided into two branches, a low-frequency acoustical and a high-frequency optical plasmon branch. In the quantum case, we have found that the dispersion relation is substantially modified when the electron wavelength becomes large enough compared to the propagation wavelength of the electrostatic waves in the quantum plasma. We also show that the axial magnetic field manifest itself on the perturbed electron density through the quantum term and gives rise to the propagation of the electrostatic waves within the quantum plasma. As a result, the effect of the magnetic field is pronounced in the plasma dispersion relations in such a way that their curves approach to zero when the magnetic field is weak; and for the strong magnetic field, they asymptotically meet the constant lines.

  8. Competition between modes with different axial structures in gyrotrons

    SciTech Connect (OSTI)

    Khutoryan, Eduard M. [O. Ya. Usikov Institute for Radiophysics and Electronics, 12, Proskura str., Kharkiv 61085 (Ukraine); Nusinovich, Gregory S.; Sinitsyn, Oleksandr V. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742-3511 (United States)

    2014-09-15T23:59:59.000Z

    This study was motivated by some experiments in which it was found that during the voltage rise, instead of expected excitation of a high-frequency parasitic mode, the excitation of a lower-frequency parasitic mode takes place in a certain range of voltages. For explaining this fact, the dependence of start currents of possible competing modes on the beam voltage was carried out in the cold-cavity approximation and by using the self-consistent approach. It was found that in the case of cavities, which consist of the combination of a section of constant radius waveguide and a slightly uptapered waveguide, these two approaches yield completely different results. Thus, experimentally observed excitation of the low-frequency parasitic mode can be explained by the self-consistent modification of the axial profile of the excited field, which has strong influence on the diffractive quality factor of competing modes. This modification is especially pronounced in the case of excitation of modes with many axial variations which can be excited in the region of beam interaction with the backward-wave component of such modes.

  9. ME 360L Compressible Flow and Turbomachinery ABET EC2000 syllabus

    E-Print Network [OSTI]

    Ben-Yakar, Adela

    displacement and dynamic rotating machinery; pumps, compressors, and turbines; performance characteristics. Centrifugal Fans, Blowers, and Compressors (1) 20. Flow over an Airfoil 21. Axial Flow Compressors engineering and science fundamentals to real problems. e 2. Ability to formulate and solve open

  10. axial crushing loads: Topics by E-print Network

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

    right-handed fermions with opposite signs, may generate an equilibrium dissipationless energy flow of fermions in the direction of the field even in the presence of interactions....

  11. Maintenance and elimination of long-term axial progenitors in mouse 

    E-Print Network [OSTI]

    Wymeersch, Filip Jos

    2012-06-22T23:59:59.000Z

    Elongation of the vertebrate rostrocaudal axis depends on localised populations of axial progenitors. Previous work has demonstrated the presence of Neuromesodermal (NM) progenitors that behave a ...

  12. The $N-?$ Weak Axial-Vector Amplitude $C_{5}^a(0)$

    E-Print Network [OSTI]

    Milton Dean Slaughter

    1999-03-01T23:59:59.000Z

    The weak $N-\\Delta$ axial-vector transition amplitude $$ - important in $N^{*}$ production processes in general and in isobar models describing $\

  13. Progress in Z-Pinch driven dynamic-hohlraums for high-temperature radiation-flow and ICF experiments at Sandia National Laboratories.

    SciTech Connect (OSTI)

    Bailey, James E.; Haines, Malcolm G. (Imperial College, London, United Kingdom); Chandler, Gordon Andrew; Bliss, David Emery; Olson, Richard Edward; Sanford, Thomas W. L.; Olson, Craig Lee; Nash, Thomas J.; Ruiz, Carlos L.; Matzen, Maurice Keith; Idzorek, George C. (Los Alamos National Laboratory, Los Alamos, NM); Stygar, William A.; Apruzese, John P. (Naval Research Laboratory, Washington DC); Cuneo, Michael Edward; Cooper, Gary Wayne (University of New Mexico, Albuquerque, NM); Chittenden, Jeremy Paul (Imperial College, London, United Kingdom); Chrien, Robert E. (Los Alamos National Laboratory, Los Alamos, NM); Slutz, Stephen A.; Mock, Raymond Cecil; Leeper, Ramon Joe; Sarkisov, Gennady Sergeevich (Ktech Corporation, Albuquerque, NM); Peterson, Darrell L. (Los Alamos National Laboratory, Los Alamos, NM); Lemke, Raymond William; Mehlhorn, Thomas Alan; Roderick, Norman Frederick (University of New Mexico, Albuquerque, NM); Watt, Robert G. (Los Alamos National Laboratory, Los Alamos, New MM)

    2004-06-01T23:59:59.000Z

    Progress in understanding the physics of dynamic-hohlraums is reviewed for a system capable of generating 13 TW of axial radiation for high temperature (>200 eV) radiation-flow experiments and ICF capsule implosions.

  14. A benchmark study of 2D and 3D finite element calculations simulating dynamic pulse buckling tests of cylindrical shells under axial impact

    SciTech Connect (OSTI)

    Hoffman, E.L.; Ammerman, D.J.

    1993-08-01T23:59:59.000Z

    A series of tests investigating dynamic pulse buckling of a cylindrical shell under axial impact is compared to several finite element simulations of the event. The purpose of the study is to compare the performance of the various analysis codes and element types with respect to a problem which is applicable to radioactive material transport packages, and ultimately to develop a benchmark problem to qualify finite element analysis codes for the transport package design industry.

  15. Creep Testing Plastic-Bonded Explosives in Uni-axial Compression

    SciTech Connect (OSTI)

    Gagliardi, F J; Cunningham, B J

    2008-03-13T23:59:59.000Z

    High fidelity measurements of time-dependent strain in the plastic-bonded explosives LX-17-1 and PBX 9502 have been performed under constant, uni-axial, compressive load using a custom designed apparatus. The apparatus uses a combination of extensometers and linear variable differential transformers coupled with a data acquisition system, thermal controls, and gravitational loading. The materials being tested consist of a crystalline explosive material mixed with a polymeric binder. The behavior of each material is related to the type of explosive and to the percentage and type of binder. For any given plastic-bonded explosive, the creep behavior is also dependent on the stress level and test temperature. Experiments were conducted using a 3 x 3 stress-temperature matrix with a temperature range of 24 C to 70 C and with stresses ranging from 250-psi to 780-psi. Analysis of the data has shown that logarithmic curve fits provide an accurate means of quantification and facilitate a long-term predictive capability. This paper will discuss the design of the apparatus, experimental results, and analyses.

  16. Nuclear reactor control rod with uniformly changeable axial worth

    SciTech Connect (OSTI)

    Freeman, T.R.

    1989-04-11T23:59:59.000Z

    A control rod is described for use in a nuclear reactor core to provide xenon compensation, comprising: (a) an elongated inner cylindrical member having a lower end; and (b) an elongated outer cylindrical member surrounding the inner member and having a lower end with concentrically-arranged inner and outer edge portions defined thereon; (c) each of the members being composed of alternating poison and nonpoison regions; (d) the inner member being axially movable relative to the outer member to adjust the degree to which the poison regions of the members overlap with the nonpoison regions thereof and thereby change the overall worth of the rod; and (e) the lower end of the inner member having defined thereon a radially outwardly projecting ledge for supporting in a rest relationship thereon the lower end of the outer member at only its inner edge portion for retaining the outer member about the inner member.

  17. Nucleon axial form factors from two-flavour Lattice QCD

    E-Print Network [OSTI]

    P. M. Junnarkar; S. Capitani; D. Djukanovic; G. von Hippel; J. Hua; B. Jäger; H. B. Meyer; T. D. Rae; H. Wittig

    2014-11-21T23:59:59.000Z

    We present preliminary results on the axial form factor $G_A(Q^2)$ and the induced pseudoscalar form factor $G_P(Q^2)$ of the nucleon. A systematic analysis of the excited-state contributions to form factors is performed on the CLS ensemble `N6' with $m_\\pi = 340 \\ \\text{MeV}$ and lattice spacing $a \\sim 0.05 \\ \\text{fm}$. The relevant three-point functions were computed with source-sink separations ranging from $t_s \\sim 0.6 \\ \\text{fm}$ to $t_s \\sim \\ 1.4 \\ \\text{fm}$. We observe that the form factors suffer from non-trivial excited-state contributions at the source-sink separations available to us. It is noted that naive plateau fits underestimate the excited-state contributions and that the method of summed operator insertions correctly accounts for these effects.

  18. Fluid flow monitoring device

    DOE Patents [OSTI]

    McKay, M.D.; Sweeney, C.E.; Spangler, B.S. Jr.

    1993-11-30T23:59:59.000Z

    A flow meter and temperature measuring device are described comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips. 7 figures.

  19. Fluid flow monitoring device

    DOE Patents [OSTI]

    McKay, Mark D. (1426 Socastee Dr., North Augusta, SC 29841); Sweeney, Chad E. (3600 Westhampton Dr., Martinez, GA 30907-3036); Spangler, Jr., B. Samuel (2715 Margate Dr., Augusta, GA 30909)

    1993-01-01T23:59:59.000Z

    A flow meter and temperature measuring device comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips.

  20. A Moore-Greitzer axial compressor model with spool Jan Tommy Gravdahl and Olav Egeland

    E-Print Network [OSTI]

    Gravdahl, Jan Tommy

    A Moore-Greitzer axial compressor model with spool dynamics. Jan Tommy Gravdahl and Olav Egeland, N-7034 Trondheim, Norway Email: fTommy.Gravdahl,Olav.Egelandg@itk.ntnu.no Abstract The compressor-parameter on the post stall transients of an axial compressor is demonstrated through simulations of a compression

  1. On the linear stability of the extreme Kerr black hole under axially symmetric perturbations

    E-Print Network [OSTI]

    Sergio Dain; Ivan Gentile de Austria

    2014-09-19T23:59:59.000Z

    We prove that for axially symmetric linear gravitational perturbations of the extreme Kerr black hole there exists a positive definite and conserved energy. This provides a basic criteria for linear stability in axial symmetry. In the particular case of Minkowski, using this energy we also prove pointwise boundedness of the perturbation in a remarkable simple way.

  2. 1 Mayne & Schneider EVALUATING AXIAL DRILLED SHAFT RESPONSE BY SEISMIC CONE

    E-Print Network [OSTI]

    Mayne, Paul W.

    1 Mayne & Schneider EVALUATING AXIAL DRILLED SHAFT RESPONSE BY SEISMIC CONE Paul W. Mayne1 , M using the results of seismic piezocone penetration tests (SCPTU) to provide continuous profiles of small to discuss the use of seismic piezocone testing for the evaluation of both axial capacity (obtained from

  3. Pressure balanced drag turbine mass flow meter

    DOE Patents [OSTI]

    Dacus, Michael W. (Gilbert, AR); Cole, Jack H. (Fayetteville, AR)

    1982-01-01T23:59:59.000Z

    The density of the fluid flowing through a tubular member may be measured by a device comprising a rotor assembly suspended within the tubular member, a fluid bearing medium for the rotor assembly shaft, independent fluid flow lines to each bearing chamber, and a scheme for detection of any difference between the upstream and downstream bearing fluid pressures. The rotor assembly reacts to fluid flow both by rotation and axial displacement; therefore concurrent measurements may be made of the velocity of blade rotation and also bearing pressure changes, where the pressure changes may be equated to the fluid momentum flux imparted to the rotor blades. From these parameters the flow velocity and density of the fluid may be deduced.

  4. Pressure balanced drag turbine mass flow meter

    DOE Patents [OSTI]

    Dacus, M.W.; Cole, J.H.

    1980-04-23T23:59:59.000Z

    The density of the fluid flowing through a tubular member may be measured by a device comprising a rotor assembly suspended within the tubular member, a fluid bearing medium for the rotor assembly shaft, independent fluid flow lines to each bearing chamber, and a scheme for detection of any difference between the upstream and downstream bearing fluid pressures. The rotor assembly reacts to fluid flow both by rotation and axial displacement; therefore concurrent measurements may be made of the velocity of blade rotation and also bearing pressure changes, where the pressure changes may be equated to the fluid momentum flux imparted to the rotor blades. From these parameters the flow velocity and density of the fluid may be deduced.

  5. Tuning linear and nonlinear optical properties of wurtzite GaN by c-axial stress

    E-Print Network [OSTI]

    Cai, Duanjun; 10.1088/0022-3727/42/18/185107

    2009-01-01T23:59:59.000Z

    We study the linear and nonlinear optical properties of wurtzite GaN under c-axial stress field, using density functional theory calculations. The fully structural optimization at each c-axial strain was performed. The calculated dielectric functions show that tensile c-axial strain effectively improves the linear optical efficiency, especially for the band-edge transitions, and significantly increase the mobility of electrons in the conduction band. Second-order nonlinear optical susceptibilities show that the tensile c-axial strain will enhance the zero- and low-frequency nonlinear responses of GaN. The enhancement of the nonlinear optical property is explained by the reduction of the polarization of wurtzite GaN under tensile c-axial strains. Based on these findings, we propose a method for improving the electrical and optical properties of the crystal through imposing appropriate stress on the high symmetry crystalline directions.

  6. Dispersion relation and growth rate in a Cherenkov free electron laser: Finite axial magnetic field

    SciTech Connect (OSTI)

    Kheiri, Golshad; Esmaeilzadeh, Mahdi [Department of Physics, Iran University of Science and Technology, Tehran 16844 (Iran, Islamic Republic of)] [Department of Physics, Iran University of Science and Technology, Tehran 16844 (Iran, Islamic Republic of)

    2013-12-15T23:59:59.000Z

    A theoretical analysis is presented for dispersion relation and growth rate in a Cherenkov free electron laser with finite axial magnetic field. It is shown that the growth rate and the resonance frequency of Cherenkov free electron laser increase with increasing axial magnetic field for low axial magnetic fields, while for high axial magnetic fields, they go to a saturation value. The growth rate and resonance frequency saturation values are exactly the same as those for infinite axial magnetic field approximation. The effects of electron beam self-fields on growth rate are investigated, and it is shown that the growth rate decreases in the presence of self-fields. It is found that there is an optimum value for electron beam density and Lorentz relativistic factor at which the maximum growth rate can take place. Also, the effects of velocity spread of electron beam are studied and it is found that the growth rate decreases due to the electron velocity spread.

  7. Axial magnetic field and toroidally streaming fast ions in the dense plasma focus are natural consequences of conservation laws in the curved axisymmetric geometry of the current sheath

    SciTech Connect (OSTI)

    Auluck, S. K. H. [Physics Group, Bhabha Atomic Research Center, Mumbai 400085 (India)

    2014-10-15T23:59:59.000Z

    Direct measurement of axial magnetic field in the PF-1000 dense plasma focus (DPF), and its reported correlation with neutron emission, call for a fresh look at previous reports of existence of axial magnetic field component in the DPF from other laboratories, and associated data suggesting toroidal directionality of fast ions participating in fusion reactions, with a view to understand the underlying physics. In this context, recent work dealing with application of the hyperbolic conservation law formalism to the DPF is extended in this paper to a curvilinear coordinate system, which reflects the shape of the DPF current sheath. Locally unidirectional shock propagation in this coordinate system enables construction of a system of 7 one-dimensional hyperbolic conservation law equations with geometric source terms, taking into account all the components of magnetic field and flow velocity. Rankine-Hugoniot jump conditions for this system lead to expressions for the axial magnetic field and three components of fluid velocity having high ion kinetic energy.

  8. Air flow through common type window openings

    E-Print Network [OSTI]

    Holleman, Theo Rufus

    1951-01-01T23:59:59.000Z

    surface pressures surrounding it? WIM O TA L E AIR WASHER LOUVERS- EXCELSIOR MAT WATER SPRAY ~-- ? EGG CRATE ~ ? CHEESE -CLOTH / Figure 4 Wind Tunnel (Flan and Section) Courtesy of Texas Engineering Exgerirent Station psgure 4-p Wind Tunnel...

  9. 5, 11751204, 2008 Surface flow types

    E-Print Network [OSTI]

    Boyer, Edmond

    ., 2002; Biggs et al., 2005; Brooks et al., 2005). Hydraulic conditions influence biota directly on the supply5 of dissolved gases and nutrients for metabolic processes (Quinn et al., 1996; Biggs et al., 2005).

  10. Applications in MPC and Network Flows

    E-Print Network [OSTI]

    2013-05-08T23:59:59.000Z

    control should be performed using the least amount of energy. Network flow ...... some type of energy consumption that we want to minimize. ...... Trends Mach.

  11. 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.

  12. Flow chamber

    DOE Patents [OSTI]

    Morozov, Victor (Manassas, VA)

    2011-01-18T23:59:59.000Z

    A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

  13. Flow Measurement with Tangential Paddlewheel Flow Meters: Analysis of Experimental Results and in-situ Diagnostics

    E-Print Network [OSTI]

    Watt, J. B.; Haberl, J. S.

    the premature drop-out of magnetic-type tangential paddlewheel sensors, as well as several in-situ diagnostic measures for ascertaining whether or not a flow meter is experiencing turbulent conditions or if a flow sensor's output signal is suffering a degraded... per second for magnetic-type, and 0.5 to 2 feet per second for non-magnetic-type flow sensors deviated from the actual flow by 20% or more which makes the measurement of flow and thermal energy use in this regime highly suspect. Figure 4 also indicates...

  14. Geological flows

    E-Print Network [OSTI]

    Yu. N. Bratkov

    2008-11-19T23:59:59.000Z

    In this paper geology and planetology are considered using new conceptual basis of high-speed flow dynamics. Recent photo technics allow to see all details of a flow, 'cause the flow is static during very short time interval. On the other hand, maps and images of many planets are accessible. Identity of geological flows and high-speed gas dynamics is demonstrated. There is another time scale, and no more. All results, as far as the concept, are new and belong to the author. No formulae, pictures only.

  15. Determination of the ?(1232) axial and pseudoscalar form factors from lattice QCD

    E-Print Network [OSTI]

    Alexandrou, Constantia

    We present a lattice QCD calculation of the ?(1232) matrix elements of the axial-vector and pseudoscalar currents. The decomposition of these matrix elements into the appropriate Lorentz invariant form factors is carried ...

  16. Møller Energy-Momentum Complex for an Axially Symmetric Scalar Field

    E-Print Network [OSTI]

    I. Radinschi

    2002-03-25T23:59:59.000Z

    We calculate the energy-distribution for an axially symmetric scalar field in the M{\\o}ller prescription. The total energy is given by the parameter m of the space-time.

  17. On the solution of the static Maxwell system in axially symmetric inhomogeneous media

    E-Print Network [OSTI]

    Kira V. Khmelnytskaya; Vladislav V. Kravchenko; Hector Oviedo

    2007-04-11T23:59:59.000Z

    We consider the static Maxwell system with an axially symmetric dielectric permittivity and construct complete systems of its solutions which can be used for analytic and numerical solution of corresponding boundary value problems.

  18. The effect of nonuniform axial heat flux distribution on the critical heat flux

    E-Print Network [OSTI]

    Todreas, Neil E.

    1965-01-01T23:59:59.000Z

    A systematic experimental and analytic investigation of the effect of nonuniform axial heat flux distribution on critical heat rilux was performed with water in the quality condition. Utilizing a model which ascribes the ...

  19. Relativistic Hartree-Fock-Bogoliubov Theory With Density Dependent Meson Couplings in Axial Symmetry

    SciTech Connect (OSTI)

    Ebran, J.-P.; Khan, E.; Arteaga, D. Pena; Grasso, M. [Institut de Physique Nucleaire, 15 rue Georges Clemenceau 91406 Orsay Cedex (France); Vretenar, D. [Physics Department, Faculty of Science, University of Zagreb, 10 000 Zagreb (Croatia)

    2009-08-26T23:59:59.000Z

    Most nuclei on the nuclear chart are deformed, and the development of new RIB facilities allows the study of exotic nuclei near the drip lines where a successful theoretical description requires both realistic pairing and deformation approaches. Relativistic Hartree-Fock-Bogoliubov model taking into account axial deformation and pairing correlations is introduced. Preliminary illustrative results with density dependent meson-nucleon couplings in axial symmetry will be discussed.

  20. Electron Diamagnetic Effect on Axial Force in an Expanding Plasma: Experiments and Theory

    SciTech Connect (OSTI)

    Takahashi, Kazunori [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Department of Electrical Engineering and Computer Science, Iwate University, Morioka 020-8551 (Japan); Lafleur, Trevor; Charles, Christine; Alexander, Peter; Boswell, Rod W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2011-12-02T23:59:59.000Z

    The axial force imparted from a magnetically expanding current-free plasma is directly measured for three different experimental configurations and compared with a two-dimensional fluid theory. The force component solely resulting from the expanding field is directly measured and identified as an axial force produced by the azimuthal current due to an electron diamagnetic drift and the radial component of the magnetic field. The experimentally measured forces are well described by the theory.

  1. Neutron tomography of axially symmetric objects using 14 MeV neutrons from a portable neutron generator

    SciTech Connect (OSTI)

    Andersson, P., E-mail: peter.andersson@physics.uu.se; Andersson-Sunden, E.; Sjöstrand, H.; Jacobsson-Svärd, S. [Department of Physics and Astronomy, Division of Applied Nuclear Physics, Uppsala University, Lägerhyddsgatan 1, 751 20 Uppsala (Sweden)

    2014-08-01T23:59:59.000Z

    In nuclear boiling water reactor cores, the distribution of water and steam (void) is essential for both safety and efficiency reasons. In order to enhance predictive capabilities, void distribution assessment is performed in two-phase test-loops under reactor-relevant conditions. This article proposes the novel technique of fast-neutron tomography using a portable deuterium-tritium neutron generator to determine the time-averaged void distribution in these loops. Fast neutrons have the advantage of high transmission through the metallic structures and pipes typically concealing a thermal-hydraulic test loop, while still being fairly sensitive to the water/void content. However, commercially available fast-neutron generators also have the disadvantage of a relatively low yield and fast-neutron detection also suffers from relatively low detection efficiency. Fortunately, some loops are axially symmetric, a property which can be exploited to reduce the amount of data needed for tomographic measurement, thus limiting the interrogation time needed. In this article, three axially symmetric test objects depicting a thermal-hydraulic test loop have been examined; steel pipes with outer diameter 24 mm, thickness 1.5 mm, and with three different distributions of the plastic material POM inside the pipes. Data recorded with the FANTOM fast-neutron tomography instrument have been used to perform tomographic reconstructions to assess their radial material distribution. Here, a dedicated tomographic algorithm that exploits the symmetry of these objects has been applied, which is described in the paper. Results are demonstrated in 20 rixel (radial pixel) reconstructions of the interior constitution and 2D visualization of the pipe interior is demonstrated. The local POM attenuation coefficients in the rixels were measured with errors (RMS) of 0.025, 0.020, and 0.022 cm{sup ?1}, solid POM attenuation coefficient. The accuracy and precision is high enough to provide a useful indication on the flow mode, and a visualization of the radial material distribution can be obtained. A benefit of this system is its potential to be mounted at any axial height of a two-phase test section without requirements for pre-fabricated entrances or windows. This could mean a significant increase in flexibility of the void distribution assessment capability at many existing two-phase test loops.

  2. Flow field studies of a new series of turbulent premixed stratified flames

    SciTech Connect (OSTI)

    Seffrin, F.; Fuest, F.; Dreizler, A. [Technische Universitaet Darmstadt, Center of Smart Interfaces, Reaktive Stroemungen und Messtechnik, Petersenstr. 32, 64287 Darmstadt (Germany); Geyer, D. [Hochschule Darmstadt, Thermodynamik und Alternative Antriebe, Haardtring 100, 64295 Darmstadt (Germany)

    2010-02-15T23:59:59.000Z

    This paper presents a new burner design for lean premixed stratified combustion for experiments to validate models for numerical simulations. The burner demonstrates combustion phenomena relevant to technological applications, where flames are often turbulent, lean premixed, and stratified. The generic burner was designed for high Reynolds number flows and can stabilize a variety of different lean premixed flames. The burner's design and its versatile operational conditions are introduced. Shear, stratification, and fuel type are parametrically varied to provide a sound database of related flow configurations. Reacting and corresponding non-reacting configurations are examined. Experimental setups and the results of laser Doppler velocimetry (LDV) and particle image velocimetry (PIV) are presented and discussed. LDV measurements provide radial profiles of mean axial velocity, mean radial velocity, and turbulent kinetic energy as well as integral time scales. High-speed PIV is introduced as a novel technique to determine integral time and length scales and provide 2D 2-component velocity fields and related quantities, such as vorticity. (author)

  3. PERFORMANCE IMPROVEMENT OF CROSS-FLOW FILTRATION FOR HIGH LEVEL WASTE TREATMENT

    SciTech Connect (OSTI)

    Duignan, M.; Nash, C.; Poirier, M.

    2011-01-12T23:59:59.000Z

    In the interest of accelerating waste treatment processing, the DOE has funded studies to better understand filtration with the goal of improving filter fluxes in existing cross-flow equipment. The Savannah River National Laboratory (SRNL) was included in those studies, with a focus on start-up techniques, filter cake development, the application of filter aids (cake forming solid precoats), and body feeds (flux enhancing polymers). This paper discusses the progress of those filter studies. Cross-flow filtration is a key process step in many operating and planned waste treatment facilities to separate undissolved solids from supernate slurries. This separation technology generally has the advantage of self-cleaning through the action of wall shear stress created by the flow of waste slurry through the filter tubes. However, the ability of filter wall self-cleaning depends on the slurry being filtered. Many of the alkaline radioactive wastes are extremely challenging to filtration, e.g., those containing compounds of aluminum and iron, which have particles whose size and morphology reduce permeability. Unfortunately, low filter flux can be a bottleneck in waste processing facilities such as the Savannah River Modular Caustic Side Solvent Extraction Unit and the Hanford Waste Treatment Plant. Any improvement to the filtration rate would lead directly to increased throughput of the entire process. To date increased rates are generally realized by either increasing the cross-flow filter axial flowrate, limited by pump capacity, or by increasing filter surface area, limited by space and increasing the required pump load. SRNL set up both dead-end and cross-flow filter tests to better understand filter performance based on filter media structure, flow conditions, filter cleaning, and several different types of filter aids and body feeds. Using non-radioactive simulated wastes, both chemically and physically similar to the actual radioactive wastes, the authors performed several tests to demonstrate increases in filter performance. With the proper use of filter flow conditions and filter enhancers, filter flow rates can be increased over rates currently realized today.

  4. An experimental investigation of flow control for supersonic inlets

    E-Print Network [OSTI]

    Titchener, Neil

    2013-07-09T23:59:59.000Z

    and in severe cases can lead to engine surge. In the early days of inlet design pressure recovery was generally considered the most im- portant parameter in inlet flow, however, the development of axial compressors with higher tip speeds and blade loadings... descriptors shown above. 7 Chapter 2. Inlet Design–A Brief Introduction For more details on distortion, especially the influence of unsteadiness, the reader should refer to the details of the flight testing trouble encountered with the F-111 described...

  5. Rotordynamic characteritics of incompressible-flow labyrinth seals

    E-Print Network [OSTI]

    Ghali, Anupama

    1993-01-01T23:59:59.000Z

    ) . Parsons (1938) was apparently the first to introduce the labyrinth seal in his development of a steam turbine near the turn of the century The objective of the seal is to create a highly frictional flow path between high-pressure and low... to point out the unstable vibrations due to labyrinth seals. He discovered that the circumferential variation of pressure in the labyrinth seal caused excitation forces, which in turn were responsible for the rotor whirl in axial compressors...

  6. Operation of a test bed axial-gap brushless DC rotor with a superconducting stator

    SciTech Connect (OSTI)

    McKeever, J.W.; Sohns, C.W.; Schwenterly, S.W.; Young, R.W. Sr.; Campbell, V.W.; Hickey, M.H.; Ott, G.W. [Oak Ridge National Lab., TN (United States); Bailey, J.M. [Univ. of Tennessee, Knoxville, TN (United States)

    1994-12-31T23:59:59.000Z

    A variable-speed axial-gap motor with a stator consisting of four liquid helium cooled superconducting electromagnets (two pole pairs) was built and proof tested up to 608 rpm in November 1990 as a tool for joint industry-laboratory evaluation of coils fabricated from high-temperature oxide superconductors. A second rotor was fabricated with improved material, winding configuration, and wire type, and the drive system was modified to eliminate current spiking. The modified motor was characterized to design speed, 188 rad/s (1800 rpm), to acquire a performance baseline for future comparison with that of high-temperature superconducting (HTS) wire. As it becomes commercially available, HTS wire will replace the low-temperature electromagnet wire in a stator modified to control wire temperatures between 4 K and 77 K. Measurements of the superconducting electromagnetic field and locked rotor torque as functions of cryocurrent and dc current through two phases of the rotor, respectively, provided data to estimate power that could be developed by the rotor. Back emf and parasitic mechanical and electromagnetic drag torques were measured as functions of angular velocity to calculate actual rotor power developed and to quantify losses, which reduce the motor`s efficiency. A detailed measurement of motor power at design speed confirmed the developed power equation. When subsequently operated at the 33-A maximum available rotor current, the motor delivered 15.3 kW (20.5 hp) to the load. In a final test, the cryostat was operated at 2500 A, 200 A below its critical current. At rotor design current of 60 A and 2500 A stator current, the extrapolated developed power would be 44.2 kW (59.2 hp) with 94% efficiency.

  7. ANALYSIS OF THE AXIAL GAP VS FIBERBOARD MOISTURE CONTENT IN A 9975 SHIPPING PACKAGE

    SciTech Connect (OSTI)

    Daugherty, W.

    2013-09-30T23:59:59.000Z

    The fiberboard assembly within a 9975 shipping package contains a modest amount of moisture, which can migrate to the cooler regions of the package when an internal heat load is present. Typically, this leads to increased moisture levels in the bottom fiberboard layers, along with elevated chloride levels which can leach from the fiberboard. Concerns have been raised that this condition could lead to corrosion of the stainless steel drum. It has been postulated that checking the axial gap at the top of the package against the current 1 inch maximum criterion provides a sufficient indication regarding the integrity of the fiberboard and drum. This report estimates the increase in axial gap that might be expected for a given moisture increase in the bottom fiberboard layers, and the likelihood that the increase will create a nonconforming condition that will lead to identification of the moisture increase. Using data relating the fiberboard moisture content with the degree of compaction under load, the present analysis indicates that the axial gap will increase by 0.282 inch as the bottom fiberboard layers approach the saturation point. This increase will cause approximately 58% of packages with otherwise nominal package component dimensions to fail the axial gap criterion, based on a survey of axial gap values recorded in K-Area surveillance activities. As the moisture content increases above saturation, the predicted increase in axial gap jumps to 0.405 inch, which would result in 92% or more of all packages failing the axial gap criterion. The data and analysis described in this report are specific to cane fiberboard. While it is expected that softwood fiberboard will behave similarly, such behavior has not yet been demonstrated.

  8. Tornado type wind turbines

    DOE Patents [OSTI]

    Hsu, Cheng-Ting (Ames, IA)

    1984-01-01T23:59:59.000Z

    A tornado type wind turbine has a vertically disposed wind collecting tower with spaced apart inner and outer walls and a central bore. The upper end of the tower is open while the lower end of the structure is in communication with a wind intake chamber. An opening in the wind chamber is positioned over a turbine which is in driving communication with an electrical generator. An opening between the inner and outer walls at the lower end of the tower permits radially flowing air to enter the space between the inner and outer walls while a vertically disposed opening in the wind collecting tower permits tangentially flowing air to enter the central bore. A porous portion of the inner wall permits the radially flowing air to interact with the tangentially flowing air so as to create an intensified vortex flow which exits out of the top opening of the tower so as to create a low pressure core and thus draw air through the opening of the wind intake chamber so as to drive the turbine.

  9. Cooling Flows or Heating Flows?

    E-Print Network [OSTI]

    James Binney

    2003-10-08T23:59:59.000Z

    It is now clear that AGN heat cooling flows, largely by driving winds. The winds may contain a relativistic component that generates powerful synchrotron radiation, but it is not clear that all winds do so. The spatial and temporal stability of the AGN/cooling flow interaction are discussed. Collimation of the winds probably provides spatial stability. Temporal stability may be possible only for black holes with masses above a critical value. Both the failure of cooling flows to have adiabatic cores and the existence of X-ray cavities confirm the importance of collimated outflows. I quantify the scale of the convective flow that the AGN Hydra would need to drive if it balanced radiative inward flow by outward flow parallel to the jets. At least in Virgo any such flow must be confined to r<~20 kpc. Hydrodynamical simulations suggest that AGN outbursts cannot last longer than ~25 Myr. Data for four clusters with well studied X-ray cavities suggests that heating associated with cavity formation approximately balances radiative cooling. The role of cosmic infall and the mechanism of filament formation are briefly touched on.

  10. Effect of Axial Loading on Quench Performance in Nb3Sn Magnets

    SciTech Connect (OSTI)

    Ambrosio, G.; Bordini, B.; Caspi, S.; Dietderich, D.R.; Felice, H.; Hafalia, A.R.; Hannaford, C.R.; Lizarazo, J.; Lietzke, A.F.; McInturff, A.D.; Sabbi, G.L.; DiMarco, J.D.; Tartaglia, M.; Vedrice, P.; Ferracin, P.

    2008-06-01T23:59:59.000Z

    A series of tests has been performed at Lawrence Berkeley National Laboratory (LBNL) and Fermi National Accelerator Laboratory (FNAL) with the goal of assessing the influence of coil axial pre-load on Nb{sub 3}Sn magnet training. The tests involved two subscale Nb{sub 3}Sn magnets: SQ02, a quadrupole magnet fabricated as part of the US LHC Accelerator Research Program (LARP), and SD01, a dipole magnet developed in collaboration between CEA/Saclay and LBNL. Both magnets used similar Nb{sub 3}Sn flat racetrack coils from LBNL Subscale Magnet Program, and implemented an axial support system composed of stainless steel end-plates and aluminum rods. The system was designed to withstand full longitudinal electro-magnetic forces and provide controllable preloads. Quench performances, training, and quench locations have been recorded in various axial loading conditions. Test results are reported.

  11. Flexural support member having a high ratio of lateral-to-axial stiffness

    DOE Patents [OSTI]

    Haas, W.M.B.

    1983-06-23T23:59:59.000Z

    A convoluted flexible support structure is provided which is capable of supplying a lateral to axial spring rate in excess of 1000 to 1. A support member in the form of a steel disc having a specified number of rather large radius, concentric convolutions and a thickness in the range of from about 0.01 to 0.02 inch has an axial stiffness of about 50 pounds/inch while the lateral stiffness is about 100,000 pounds/inch. The support member may be used to support a vibration device where the lateral motion of the vibrator must be highly restricted while providing relatively free axial displacement of about +-0.25 inch.

  12. Axial seal system for a gas turbine steam-cooled rotor

    DOE Patents [OSTI]

    Mashey, Thomas Charles (Anderson, SC)

    2002-01-01T23:59:59.000Z

    An axial seal assembly is provided at the interface between adjacent wheels and spacers of a gas turbine rotor and disposed about tubes passing through openings in the rotor adjacent the rotor rim and carrying a thermal medium. Each seal assembly includes a support bushing for supporting a land of the thermal medium carrying tube, an axially registering seat bushing disposed in the opposed opening and a frustoconical seal between the seal bushing and seat. The seal bushing includes a radial flange having an annular recess for retaining the outer diameter edge of the seal, while the seat bushing has an axially facing annular surface forming a seat for engagement by the inner diameter edge of the seal.

  13. Production of low axial energy spread ion beams with multicusp sources

    SciTech Connect (OSTI)

    Lee, Y.H.Y. [Univ. of California, Berkeley, CA (United States)

    1998-05-01T23:59:59.000Z

    Multicusp ion sources are capable of producing ions with low axial energy spread which are necessary in applications such as: ion projection lithography (IPL) and focused ion beams for the next generation lithographic tools and nuclear science experiments such as radioactive ion beam production. The axial ion energy spread for multicusp source is approximately 6 eV which is too large for IPL and radioactive ion beam applications. The addition of a magnetic filter which consists of a pair of permanent magnets to the multicusp source reduces the energy spread considerably. The reduction is due to the improvement in the uniformity of the axial plasma potential distribution in the discharge region. Axial ion energy spread of the filament driven ion source has been measured using three different techniques. In all cases, it was found to be less than 2 eV. Energy spread of the radio frequency (RF) driven source has also been explored, and it was found to be less than 3 eV with the proper RF-shielding. A new multicusp source configuration has been designed and constructed to further reduce the energy spread. To achieve a more uniform axial plasma potential distribution, a cylindrical magnetic filter has been designed and constructed for a 2-cm-diameter source. This new source configuration, the co-axial source, is new in its kind. The energy spread in this source has been measured to be a record low of 0.6 eV. Because of the novelty of this device, some plasma parameters inside the source have been studied. Langmuir probe has been used to measure the plasma potential, the electron temperature and the density distribution.

  14. Cardy-Verlinde formula for an axially symmetric dilaton-axion black hole

    E-Print Network [OSTI]

    Mubasher Jamil; M. Akbar; M. R. Setare

    2011-05-30T23:59:59.000Z

    It is shown that the Bekenstein-Hawking entropy of an axially symmetric dilaton-axion black hole can be expressed as a Cardy-Verlinde formula. By utilizing the first order quantum correction in the Bekenstein-Hawking entropy we find the modified expressions for the Casimir energy and pure extensive energy. The first order correction to the Cardy-Verlinde formula in the context of axially symmetric dilaton-axion black hole are obtained with the use of modified Casimir and pure extensive energies.

  15. Note: Simultaneous measurement of transverse speed and axial velocity from a single optical beam

    SciTech Connect (OSTI)

    Moro, Erik A.; Briggs, Matthew E. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2013-01-15T23:59:59.000Z

    A method is introduced for simultaneously measuring transverse speed and axial velocity using a single optical beam and a standard photon Doppler velocimetry (PDV) sensing architecture. This result is of particular interest given the recent, widespread use of PDV and the fact that optical velocimetry has thus far been limited to measuring motion in one dimension per probe. Further, this result demonstrates that both axial velocity data and transverse speed data (at least qualitative) may be obtained entirely through signal analysis; not requiring hardware modification. This result is immediately relevant to analyses of existing PDV data and to future efforts in high-speed optical velocimetry.

  16. An axially propagating two-stream instability in the Hall thruster plasma

    SciTech Connect (OSTI)

    Tsikata, S., E-mail: sedina.tsikata@cnrs-orleans.fr [ICARE, CNRS (UPR 3021), 1C ave. de la Recherche Scientifique, 45071 Orléans (France); Cavalier, J. [Institute of Plasma Physics ASCR, Prague (Czech Republic); Héron, A. [CPHT, CNRS (UMR 7644), Ecole Polytechnique, Route de Saclay, 91128 Palaiseau (France); Honoré, C.; Grésillon, D. [LPP, CNRS (UMR 7648), Ecole Polytechnique-Univ. Paris-Sud-UPMC Univ. Paris 06, Route de Saclay, 91128 Palaiseau (France); Lemoine, N.; Coulette, D. [IJL, CNRS (UMR 7198), Université de Lorraine, BP 70239, 54506 Vandoeuvre-lès-Nancy (France)

    2014-07-15T23:59:59.000Z

    Collective Thomson scattering experiments reveal the presence of high-frequency, axial electron density fluctuations at millimetric wavelengths in the Hall thruster plasma. The properties of these fluctuations are investigated experimentally and via linear kinetic theory. The relative drift of electrons and ions in the axial direction is found to be insufficient to cause excitation of the observed mode. Instead, the mode is determined to be a two-stream instability arising due to the velocity difference between singly and doubly charged ion populations in the plume.

  17. Droplet sizes, dynamics and deposition in vertical annular flow

    SciTech Connect (OSTI)

    Lopes, J C.B.; Dukler, A E

    1985-10-01T23:59:59.000Z

    The role of droplets in vertical upwards annular flow is investigated, focusing on the droplet size distributions, dynamics, and deposition phenomena. An experimental program was performed based on a new laser optical technique developed in these laboratories and implemented here for annular flow. This permitted the simultaneous measurement of droplet size, axial and radial velocity. The dependence of droplet size distributions on flow conditions is analyzed. The Upper-Log Normal function proves to be a good model for the size distribution. The mechanism controlling the maximum stable drop size was found to result from the interaction of the pressure fluctuations of the turbulent flow of the gas core with the droplet. The average axial droplet velocity showed a weak dependence on gas rates. This can be explained once the droplet size distribution and droplet size-velocity relationship are analyzed simultaneously. The surprising result from the droplet conditional analysis is that larger droplet travel faster than smaller ones. This dependence cannot be explained if the drag curves used do not take into account the high levels of turbulence present in the gas core in annular flow. If these are considered, then interesting new situations of multiplicity and stability of droplet terminal velocities are encountered. Also, the observed size-velocity relationship can be explained. A droplet deposition is formulated based on the particle inertia control. This permitted the calculation of rates of drop deposition directly from the droplet size and velocities data.

  18. Non-Newtonian fluid flow

    E-Print Network [OSTI]

    Osinski, Charles Anthony

    1963-01-01T23:59:59.000Z

    zero and unity. The Ostwald- de Waele Equation (4), commonly known as the power law, is sometimes used to describe fluid behavior of this type. The rheological equation is (4) where the parameters "k" and "n" are constant for a particular fluid... be extended to include Reynolds numbers and the type of flow determined to be laminar and/or turbulent. It is assumed that the transition from laminar to turbulent flow occurs at a Reynolds number of 2100, the numeric distribution of Reynolds numbers...

  19. Uncertainty quantification using multiscale methods for porous media flows

    E-Print Network [OSTI]

    Dostert, Paul Francis

    2009-05-15T23:59:59.000Z

    numerical models. When solving the flow and transport through heterogeneous porous media some type of upscaling or coarsening is needed due to scale disparity. We describe multiscale techniques used for solving the spatial component of the stochastic flow...

  20. Boundary Element Method for Internal Axisymmetric Flow Dr. Alexander Gokhman

    E-Print Network [OSTI]

    Gokhman, Dmitry

    to the practical cases of axisymmetric flow in Francis and Kaplan turbine passages with conical and of the method to the computation of flow in turbomachines of Kaplan and Francis types. 1 Introduction

  1. OPPDIF: A Fortran program for computing opposed-flow diffusion flames

    SciTech Connect (OSTI)

    Lutz, A.E.; Kee, R.J.; Grcar, J.F.; Rupley, F.M. [Sandia National Labs., Livermore, CA (United States). Thermal and Plasma Processes Dept.

    1997-05-01T23:59:59.000Z

    OPPDIF is a Fortran program that computes the diffusion flame between two opposing nozzles. A similarity transformation reduces the two-dimensional axisymmetric flow field to a one-dimensional problem. Assuming that the radial component of velocity is linear in radius, the dependent variables become functions of the axial direction only. OPPDIF solves for the temperature, species mass fractions, axial and radial velocity components, and radial pressure gradient, which is an eigenvalue in the problem. The TWOPNT software solves the two-point boundary value problem for the steady-state form of the discretized equations. The CHEMKIN package evaluates chemical reaction rates and thermodynamic and transport properties.

  2. Preventing Buckling of Slender Cylindrical Structures by Internal Viscous Flows

    E-Print Network [OSTI]

    Max Linshits; Amir D. Gat

    2015-02-10T23:59:59.000Z

    Viscous flows within an elastic structure apply stress on the solid-liquid interface. The stress-field created by the viscous flow can be utilized to counter stress created by external forces and thus may be applied as a tool for delaying the onset of structural failure. To illustrate this concept we study viscous flow within an elastic cylinder under compressive axial force. We obtain a closed-form expression showing an approximately linear relation between the critical buckling load and the liquid inlet pressure. Our results are validated by numerical computations. We discuss future research directions of fluid-solid composite materials which create flow under external stress, yielding enhanced resistance to structural failure.

  3. Synthesis, structural characterization and properties of aluminum (III) meso-tetraphenylporphyrin complexes axially

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ) complexes axially bonded to phosphinate anions and present their properties as supramolecular building free base (H2TPP) as starting material (Figure 1). H2TPP was treated with AlMe3 and the phosphinic acid in high yield (85-87%). Figure 2. X-ray structure of [1.EtOH] supramolecular chains. Light gray, C

  4. New Structural Model for Multicomponent Pile Cross Sections under Axial Load

    E-Print Network [OSTI]

    Horvath, John S.

    New Structural Model for Multicomponent Pile Cross Sections under Axial Load John S. Horvath, Ph.D., P.E., M.ASCE1 Abstract: Piles composed of more than one material in their cross section have been used for more than 100 years. Originally this was limited to driven steel shell or pipe piles filled

  5. MOISTURE EFFECT ON DURABILITY OF AXIALLY LOADED CONCRETE-FILLED TUBULAR FRP PILES

    E-Print Network [OSTI]

    MOISTURE EFFECT ON DURABILITY OF AXIALLY LOADED CONCRETE-FILLED TUBULAR FRP PILES Miguel Pando, Ph_rizkalla@ncsu.edu ABSTRACT Fiber reinforced polymer (FRP) composite piles are a possible foundation alternative for projects located in harsh marine environments. Problems associated with traditional pile materials used in harsh

  6. Cost effective combined axial fan and throttling valve control of ventilation rate

    E-Print Network [OSTI]

    Sengun, Mehmet Haluk

    Cost effective combined axial fan and throttling valve control of ventilation rate C.J. Taylor 1 P with Proportional-Integral-Plus (PIP) control of ventilation rate in mechanically ventilated agricultural buildings ventilation. The new combined fan/valve configuration is compared with a commercially available PID

  7. Single pulse ultrafast laser imprinting of axial dot arrays in bulk glasses C. Mauclair,1,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Single pulse ultrafast laser imprinting of axial dot arrays in bulk glasses C. Mauclair,1, A sam- ples were irradiated with 160 fs pulses from an 800 nm Ti:Sapphire amplified ultrafast laser.mauclair@univ-st-etienne.fr Compiled December 20, 2010 Ultrafast laser processing of bulk transparent materials can significantly gain

  8. Axial and radial preliminary results of the neutron radiation from miniature plasma focus devices.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Axial and radial preliminary results of the neutron radiation from miniature plasma focus devices. Introduction. The plasma focus (PF) is a dense transient plasma source of high temperature, when it operate of understanding the physics related to the plasma focus working at this limit of unexplored energy, b) to develop

  9. Earth Planets Space, 64, 113120, 2012 Upper ionosphere of Mars is not axially symmetrical

    E-Print Network [OSTI]

    Gurnett, Donald A.

    Earth Planets Space, 64, 113­120, 2012 Upper ionosphere of Mars is not axially symmetrical E to the ionosphere providing momentum and energy transfer to the upper layers of the ionospheric plasma. While dependence rather closely follow the Chapman model (Gurnett et al., 2008; Morgan et al., 2008; Withers, 2009

  10. Optimization of a Microscale, Axial-Flux, Permanent-Magnet Generator D. P. Arnold1*

    E-Print Network [OSTI]

    -phase, axial- flux, PM machine, consisting of a stator with Cu surface windings and a multi-pole SmCo PM rotor of the overall machine geometry and stator winding patterns. 2. MACHINE OVERVIEW The generator is a three back iron and a stator with Cu surface windings on a magnetically soft substrate, which serves

  11. Influence of constraints on axial growth reduction of cylindrical Li-ion battery electrode particles

    E-Print Network [OSTI]

    Jeevanjyoti Chakraborty; Colin P. Please; Alain Goriely; S. Jonathan Chapman

    2014-11-24T23:59:59.000Z

    Volumetric expansion of silicon anode particles in a lithium-ion battery during charging may lead to the generation of undesirable internal stresses. For a cylindrical particle such growth may also lead to failure by buckling if the expansion is constrained in the axial direction due to other particles or supporting structures. To mitigate this problem, the possibility of reducing axial growth is investigated theoretically by studying simple modifications of the solid cylinder geometry. First, an annular cylinder is considered with lithiation either from the inside or from the outside. In both cases, the reduction of axial growth is not found to be significant. Next, explicit physical constraints are studied by addition of a non-growing elasto-plastic material: first, an outer annular constraint on a solid silicon cylinder, and second a rod-like inner constraint for an annular silicon cylinder. In both cases, it is found that axial growth can be reduced if the yield stress of the constraining material is significantly higher than that of silicon and/or the thickness of the constraint is relatively high. Phase diagrams are presented for both the outer and the inner constraint cases to identify desirable operating zones. Finally, to interpret the phase diagrams and isolate the key physical principles two different simplified models are presented and are shown to recover important qualitative trends of the numerical simulation results.

  12. Non-Axial Octupole Deformations and Tetrahedral Symmetry in Heavy Nuclei

    SciTech Connect (OSTI)

    Mazurek, Katarzyna [Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Cracow (Poland); Dudek, Jerzy [Institut de Recherches Subatomiques, F-67037 Strasbourg Cedex 2 (France); Universite Louis Pasteur, F-67037 Strasbourg Cedex 2 (France)

    2005-11-21T23:59:59.000Z

    The total energies of about 120 nuclei in the Thorium region have been calculated within the macroscopic-microscopic method in the 5-dimensional space of deformation parameters {alpha}20, {alpha}22, {alpha}30, {alpha}32 and {alpha}40. The macroscopic energy term contains the nuclear surface-curvature dependence as proposed within the LSD approach. The microscopic energies are calculated with the Woods-Saxon single particle potential employing the universal set of parameters.We study a possible presence of the octupole axial and non-axial degrees of freedom all-over in the ({beta}, {gamma})-plane focussing on the ground-states, secondary minima and in the saddle points. In fact, a competition between axial and tri-axial octupole deformation parameters is obtained at the saddle points and in the secondary minima for many isotones with N > 136. The presence of the tetrahedral symmetry minima is predicted in numerous nuclei in the discussed region, although most of the time at relatively high excitation energies.

  13. VASCONCELOS, BARRETO: RELATIVE POSE BETWEEN AXIAL CAMERAS 1 Towards a minimal solution for the relative

    E-Print Network [OSTI]

    Barreto, Joao

    is central iff all the back-projection rays intersect in a single point in 3D, that is the viewpoint in 3D (the axis). The axial camera can be used to model vision systems and imaging situations of practical interest. Examples include any catadioptric system that combines a revolution mirror

  14. Nucleon axial charge from quenched lattice QCD with domain wall fermions

    E-Print Network [OSTI]

    Shoichi Sasaki; Kostas Orginos; Shigemi Ohta; Tom Blum; for the RBCK Collaboration

    2003-07-18T23:59:59.000Z

    We present a quenched lattice calculation of the nucleon isovector vector and axial-vector charges gV and gA. The chiral symmetry of domain wall fermions makes the calculation of the nucleon axial charge particularly easy since the Ward-Takahashi identity requires the vector and axial-vector currents to have the same renormalization, up to lattice spacing errors of order O(a^2). The DBW2 gauge action provides enhancement of the good chiral symmetry properties of domain wall fermions at larger lattice spacing than the conventional Wilson gauge action. Taking advantage of these methods and performing a high statistics simulation, we find a significant finite volume effect between the nucleon axial charges calculated on lattices with (1.2 fm)^3 and (2.4 fm)^3 volumes (with lattice spacing, a, of about 0.15 fm). On the large volume we find gA = 1.212 +/- 0.027(statistical error) +/- 0.024(normalization error). The quoted systematic error is the dominant (known) one, corresponding to current renormalization. We discuss other possible remaining sources of error. This theoretical first principles calculation, which does not yet include isospin breaking effects, yields a value of gA only a little bit below the experimental one, 1.2670 +/- 0.0030.

  15. HIGH-SPEED AXIAL-FLUX PERMANENT MAGNET MICROMOTORS WITH ELECTROPLATED WINDINGS

    E-Print Network [OSTI]

    the other. The folded-coil stator fabrication process is detailed, followed by the motor driver topology- plated multi-phase stator windings and their use in a high-speed permanent magnet micromotor. As the stator windings of an axial- flux micromotor, both single-plated folded coils, and two-layer double

  16. Proterozoic low orbital obliquity and axial-dipolar geomagnetic field from

    E-Print Network [OSTI]

    record. Magnetic inclinations are consistent with low orbital obliquity and a geocentric-axial-dipole magnetic field for most of the past two billion years, and the snowball Earth hypothesis accordingly tropical oceans6,7 . An alternative to global refrigeration invokes a high Precambrian planetary obliquity

  17. Hydrogen bonding preference of equatorial versus axial hydroxyl groups in pyran and cyclohexane rings in organic crystals

    E-Print Network [OSTI]

    de Gispert, Adrià

    Paper Hydrogen bonding preference of equatorial versus axial hydroxyl groups in pyran of the hydrogen bonding counts in crystalline pyranose monosaccharides, we noticed that equatorial hydroxyls formed more hydrogen bonds, on average, than axial groups. A survey of the Cambridge Structural Database

  18. 516 OPTICS LETTERS / Vol. 28, No. 7 / April 1, 2003 Optical bistability in axially modulated OmniGuide fibers

    E-Print Network [OSTI]

    demonstrate the feasibility of optical bistability in an axially modulated nonlinear OmniGuide fiber through516 OPTICS LETTERS / Vol. 28, No. 7 / April 1, 2003 Optical bistability in axially modulated OmniGuide fibers Marin Soljacic´, Mihai Ibanescu, Steven G. Johnson, and J. D. Joannopoulos Department of Physics

  19. Volume 152, number 4,s CHEMICAL PHYSICS LETTERS 18 November 1988 NON-INTRUSIVE MEASUREMENT OF AXIAL ELECTRIC FIELDS

    E-Print Network [OSTI]

    Cohen, Ronald C.

    Volume 152, number 4,s CHEMICAL PHYSICS LETTERS 18 November 1988 NON-INTRUSIVE MEASUREMENT OF AXIAL pertur- bations by sheath accumulation. Non-intrusive mea- surements of the electric fields through for the non- perturbative measurement of the axial electric fields in glow discharges. The A `n, + X I&+ (4

  20. Confined flow of suspensions modeled by a frictional rheology

    E-Print Network [OSTI]

    Brice Lecampion; Dmitry I. Garagash

    2014-09-19T23:59:59.000Z

    We investigate in detail the problem of confined pressure-driven laminar flow of neutrally buoyant non-Brownian suspensions using a frictional rheology based on the recent proposal of Boyer et al., 2011. The friction coefficient and solid volume fraction are taken as functions of the dimensionless viscous number I defined as the ratio between the fluid shear stress and the particle normal stress. We clarify the contributions of the contact and hydrodynamic interactions on the evolution of the friction coefficient between the dilute and dense regimes reducing the phenomenological constitutive description to three physical parameters. We also propose an extension of this constitutive law from the flowing regime to the fully jammed state. We obtain an analytical solution of the fully-developed flow in channel and pipe for the frictional suspension rheology. The result can be transposed to dry granular flow upon appropriate redefinition of the dimensionless number I. The predictions are in excellent agreement with available experimental results, when using the values of the constitutive parameters obtained independently from stress-controlled rheological measurements. In particular, the frictional rheology correctly predicts the transition from Poiseuille to plug flow and the associated particles migration with the increase of the entrance solid volume fraction. We numerically solve for the axial development of the flow from the inlet of the channel/pipe toward the fully-developed state. The available experimental data are in good agreement with our predictions. The solution of the axial development of the flow provides a quantitative estimation of the entrance length effect in pipe for suspensions. A analytical expression for development length is shown to encapsulate the numerical solution in the entire range of flow conditions from dilute to dense.

  1. Linear and nonlinear stability analysis for two-dimensional ideal magnetohydrodynamics with incompressible flows

    SciTech Connect (OSTI)

    Khater, A.H.; Moawad, S.M.; Callebaut, D.K. [Department of Mathematics, Faculty of Science, Cairo University, Beni-Suef (Egypt); Departement Natuurkunde, Campus Drie Eiken, Universiteit Antwerpen - UA, B-2610 Antwerpen (Belgium)

    2005-01-01T23:59:59.000Z

    The equilibrium and Lyapunov stability properties for two-dimensional ideal magnetohydrodynamic (MHD) plasmas with incompressible and homogeneous (i.e., constant density) flows are investigated. In the unperturbed steady state, both the velocity and magnetic field are nonzero and have three components in a Cartesian coordinate system with translational symmetry (i.e., one ignorable spatial coordinate). It is proved that (a) the solutions of the ideal MHD steady state equations with incompressible and homogeneous flows in the plane are also valid for equilibria with the axial velocity component being a free flux function and the axial magnetic field component being a constant (b) the conditions of linearized Lyapunov stability for these MHD flows in the planar case (in which the fields have only two components) are also valid for symmetric equilibria that have a nonplanar velocity field component as well as a nonplanar magnetic field component. On using the method of convexity estimates, nonlinear stability conditions are established.

  2. Non-Darcy flow in geothermal reservoirs

    SciTech Connect (OSTI)

    Zyvoloski, G.

    1982-01-01T23:59:59.000Z

    The effects of non-Darcy flow laws are investigated for two geothermal reservoir types: multiphase and Hot Dry Rock (HDR). Long-term thermal behavior is emphasized as short-term pressure transient behavior is addressed in the oil field literature. Comparisons of Darcy and non-Darcy flow laws are made.

  3. Award Types

    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 Office511041cloth DocumentationProductsAlternativeOperationalAugust AugustInstruments on theAward Types Types of

  4. Convective heat flow probe

    DOE Patents [OSTI]

    Dunn, J.C.; Hardee, H.C.; Striker, R.P.

    1984-01-09T23:59:59.000Z

    A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

  5. Radiofrequency hydrogen ion source with permanent magnets providing axial magnetic field

    SciTech Connect (OSTI)

    Oikawa, Kohei, E-mail: oikawa@ecei.tohoku.ac.jp; Saito, Yuta; Komizunai, Shota; Takahashi, Kazunori; Ando, Akira [Department of Electrical Engineering, Tohoku University, Sendai 980-8579 (Japan)] [Department of Electrical Engineering, Tohoku University, Sendai 980-8579 (Japan)

    2014-02-15T23:59:59.000Z

    Uniform axial magnetic field of about 70 G is applied to a radiofrequency (rf) hydrogen ion source by arrays of permanent magnets. The plasma density and electron temperature downstream of the source and near the magnetic filter are compared with those in the previously described ion source, where the axial field has been applied by two solenoids. The source is operated at ?350 kHz and above 10 kW rf power with a field-effect-transistor-based invertor power supply in 1.5 Pa hydrogen. The results show that the plasma density of ?10{sup 19} m{sup ?3} near the source exit and ?10{sup 18} m{sup ?3} near the magnetic filter can be obtained, which are higher than those with the solenoids.

  6. Theoretical and experimental investigation of axial power extraction from a magnetically insulated transmission line oscillator

    SciTech Connect (OSTI)

    Lemke, R.W.; DeMuth, G.E.; Biggs, A.W. (Sandia National Labs., Albuquerque, NM (USA); Air Force Weapons Lab., Kirtland AFB, NM (USA); Alabama Univ., Huntsville, AL (USA). Dept. of Electrical and Computer Engineering)

    1989-01-01T23:59:59.000Z

    The utility of the magnetically insulated transmission line oscillator (MILO) as a high power microwave source depends on how efficiently power can be extracted from it. We have designed a slow-wave stepped transformer for the purpose of axially extracting microwave power from a 3.6 GHz coaxial MILO. The slow-wave transformer design was optimized using particle-in-cell simulation, and tested in experiments performed on the HPM Simulation Division's GEMINI and GYPSY water Blumlein pulse power sources. In this paper we summarize the slow-wave stepped transformer design, and describe MILO axial power extraction experiments which yielded up to 300 MW of radiated power. 10 refs., 4 figs., 2 tabs.

  7. Axial anomaly of QED in a strong magnetic field and noncommutative anomaly

    SciTech Connect (OSTI)

    Sadooghi, N. [Department of Physics, Sharif University of Technology, P.O. Box 11365-9161, Tehran (Iran, Islamic Republic of); Institute for Studies in Theoretical Physics and Mathematics (IPM), School of Physics, P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Jafari Salim, A. [Department of Physics, Sharif University of Technology, P.O. Box 11365-9161, Tehran (Iran, Islamic Republic of)

    2006-10-15T23:59:59.000Z

    The Adler-Bell-Jackiw (ABJ) anomaly of a 3+1 dimensional QED is calculated in the presence of a strong magnetic field. It is shown that in the regime with the lowest Landau level (LLL) dominance a dimensional reduction from D=4 to D=2 dimensions occurs in the longitudinal sector of the low energy effective field theory. In the chiral limit, the resulting anomaly is therefore comparable with the axial anomaly of a two-dimensional massless Schwinger model. It is further shown that the U{sub A}(1) anomaly of QED in a strong magnetic field is closely related to the nonplanar axial anomaly of a conventional noncommutative U(1) gauge theory.

  8. Neutrino- and antineutrino-deuteron elastic scattering and the axial isoscalar nucleon current

    SciTech Connect (OSTI)

    Frederico, T.; Henley, E.M.; Pollock, S.J.; Ying, S. (Department of Physics, FM-15 and Institute for Nuclear Theory, HN-12, University of Washington, Seattle, Washington 98195 (United States))

    1992-07-01T23:59:59.000Z

    We calculate the neutrino and antineutrino elastic scattering cross section on unpolarized deuterons at energies from a few MeV to several GeV and squared momentum transfers up to 5 GeV{sup 2}. These cross sections can be used to deduce the unknown weak SU(2) isoscalar and SU(3) flavor-scalar axial-vector coupling to nucleons. This observable can be related to the strangeness axial-vector matrix element in the absence of QCD radiative or isospin-violating corrections. We show that the unknown weak magnetic vector coupling may also be gleaned from these measurements. We use different techniques at different energies, including light-cone impulse approximation at the highest energies, and show that they connect smoothly to each other.

  9. Comments on the U(1) axial symmetry and the chiral transition in QCD

    E-Print Network [OSTI]

    Enrico Meggiolaro

    2014-10-14T23:59:59.000Z

    We analyze (using a chiral effective Lagrangian model) the scalar and pseudoscalar meson mass spectrum of QCD at finite temperature, above the chiral transition at $T_c$, looking, in particular, for signatures of a possible breaking of the $U(1)$ axial symmetry above $T_c$. A detailed comparison between the case with a number of light quark flavors $N_f\\geq 3$ and the (remarkably different) case $N_f=2$ is performed.

  10. Scattering of particles by neutron stars: Time-evolutions for axial perturbations

    E-Print Network [OSTI]

    V. Ferrari; K. D. Kokkotas

    2000-08-23T23:59:59.000Z

    The excitation of the axial quasi-normal modes of a relativistic star by scattered particles is studied by evolving the time dependent perturbation equations. This work is the first step towards the understanding of more complicated perturbative processes, like the capture or the scattering of particles by rotating stars. In addition, it may serve as a test for the results of the full nonlinear evolution of binary systems.

  11. Charmless Hadronic B Decays into Vector, Axial Vector and Tensor Final States at BaBar

    SciTech Connect (OSTI)

    Gandini, Paolo; /Milan U. /INFN, Milan

    2012-04-06T23:59:59.000Z

    We present experimental measurements of branching fraction and longitudinal polarization fraction in charmless hadronic B decays into vector, axial vector and tensor final states with the final dataset of BABAR. Measurements of such kind of decays are a powerful tool both to test the Standard Model and search possible sources of new physics. In this document we present a short review of the last experimental results at BABAR concerning charmless quasi two-body decays in final states containing particles with spin 1 or spin 2 and different parities. This kind of decays has received considerable theoretical interest in the last few years and this particular attention has led to interesting experimental results at the current b-factories. In fact, the study of longitudinal polarization fraction f{sub L} in charmless B decays to vector vector (VV), vector axial-vector (VA) and axial-vector axial-vector (AA) mesons provides information on the underlying helicity structure of the decay mechanism. Naive helicity conservation arguments predict a dominant longitudinal polarization fraction f{sub L} {approx} 1 for both tree and penguin dominated decays and this pattern seems to be confirmed by tree-dominated B {yields} {rho}{rho} and B{sup +} {yields} {Omega}{rho}{sup +} decays. Other penguin dominated decays, instead, show a different behavior: the measured value of f{sub L} {approx} 0.5 in B {yields} {phi}K* decays is in contrast with naive Standard Model (SM) calculations. Several solutions have been proposed such as the introduction of non-factorizable terms and penguin-annihilation amplitudes, while other explanations invoke new physics. New modes have been investigated to shed more light on the problem.

  12. Using electron scattering to constrain the axial-vector form factor

    E-Print Network [OSTI]

    R. González-Jiménez; J. A. Caballero; T. W. Donnelly

    2015-01-16T23:59:59.000Z

    We present an analysis of elastic and quasielastic parity-violating (PV) electron scattering processes. These reactions can help to constrain the weak neutral current form factors of the nucleon that play an essential role in the description of neutrino cross sections at intermediate energies. We show that combining information from the analysis of elastic and quasielastic reactions the current knowledge on the strange and axial-vector form factors can be significantly improved.

  13. Using electron scattering to constrain the axial-vector form factor

    E-Print Network [OSTI]

    González-Jiménez, R; Donnelly, T W

    2015-01-01T23:59:59.000Z

    We present an analysis of elastic and quasielastic parity-violating (PV) electron scattering processes. These reactions can help to constrain the weak neutral current form factors of the nucleon that play an essential role in the description of neutrino cross sections at intermediate energies. We show that combining information from the analysis of elastic and quasielastic reactions the current knowledge on the strange and axial-vector form factors can be significantly improved.

  14. Manipulating Magnetism: Ru-2(5+) Paddlewheels Devoid of Axial Interactions

    SciTech Connect (OSTI)

    Chiarella, Gina M [Texas A& M University; Cotton, F. A. [Texas A& M University; Murillo, Carlos A [Texas A& M University; Ventura, Karen [University of Texas at El Paso; Vilagran, Dino [University of Texas at El Paso; Wang, Xiaoping [ORNL

    2014-01-01T23:59:59.000Z

    Variable-temperature magnetic and structural data of two pairs of diruthenium isomers, one pair having an axial ligand and the formula Ru-2(DArF)(4)Cl (where DArF is the anion of a diarylformamidine isomer and Ar = p-anisyl or m-anisyl) and the other one being essentially identical but devoid of axial ligands and having the formula [Ru-2(DArF)(4)]BF4, show that the axial ligand has a significant effect on the electronic structure of the diruthenium unit. Variable temperature crystallographic and magnetic data as well as density functional theory calculations unequivocally demonstrate the occurrence of pi interactions between the p orbitals of the chlorine ligand and the pi* orbitals in the Ru-2(5+) units. The magnetic and structural data are consistent with the existence of combined ligand sigma/metal sigma and ligand p pi/metal-d pi interactions. Electron paramagnetic resonance data show unambiguously that the unpaired electrons are in metal-based molecular orbitals.

  15. Effect of Temporal Acquisition Parameters on the Image Quality of Ultrasound Axial Strain Time-constant Elastograms

    E-Print Network [OSTI]

    Varghese, Joshua

    2011-08-02T23:59:59.000Z

    constant (TC) have been developed. The axial strain TC is a parameter that is related to the viscoelastic and poroelastic behavior of tissues. Estimation of this parameter can be done using curve fitting methods. However, the effect of temporal...

  16. Horizontal Air Flow Drying Foods at Home Safely

    E-Print Network [OSTI]

    Horizontal Air Flow Drying Foods at Home Safely Choosing a Food Dehydrator Drying is one. The thermostat should go up to 160 degrees F. The unit should have a fan or blower for air circulation. Mesh purposes. Types of Dehydrators There are two main types of dehydrators: those with vertical air flow

  17. Dynamic pulse buckling of cylindrical shells under axial impact: A benchmark study of 2D and 3D finite element calculations

    SciTech Connect (OSTI)

    Hoffman, E.L.; Ammerman, D.J.

    1995-04-01T23:59:59.000Z

    A series of tests investigating dynamic pulse buckling of a cylindrical shell under axial impact is compared to several 2D and 3D finite element simulations of the event. The purpose of the work is to investigate the performance of various analysis codes and element types on a problem which is applicable to radioactive material transport packages, and ultimately to develop a benchmark problem to qualify finite element analysis codes for the transport package design industry. During the pulse buckling tests, a buckle formed at each end of the cylinder, and one of the two buckles became unstable and collapsed. Numerical simulations of the test were performed using PRONTO, a Sandia developed transient dynamics analysis code, and ABAQUS/Explicit with both shell and continuum elements. The calculations are compared to the tests with respect to deformed shape and impact load history.

  18. Low volume flow meter

    DOE Patents [OSTI]

    Meixler, Lewis D. (East Windsor, NJ)

    1993-01-01T23:59:59.000Z

    The low flow monitor provides a means for determining if a fluid flow meets a minimum threshold level of flow. The low flow monitor operates with a minimum of intrusion by the flow detection device into the flow. The electrical portion of the monitor is externally located with respect to the fluid stream which allows for repairs to the monitor without disrupting the flow. The electronics provide for the adjustment of the threshold level to meet the required conditions. The apparatus can be modified to provide an upper limit to the flow monitor by providing for a parallel electronic circuit which provides for a bracketing of the desired flow rate.

  19. Method for operating a nuclear reactor to accommodate load follow while maintaining a substantially constant axial power distribution

    SciTech Connect (OSTI)

    Mueller, N.P.; Rossi, C.E.; Scherpereel, L.R.

    1980-09-16T23:59:59.000Z

    This invention provides a method of operating a nuclear reactor having a negative reactivity moderator temperature coefficient with the object of maintaining a uniform and symmetric xenon distribution above and below substantially the center of the core over a substantial axial length of the core during normal reactor operation including load follow. In one embodiment variations in the xenon distribution are controlled by maintaining a substantially symmetric axial power distribution. The axial offset, which is employed as an indication of the axial power distribution, is maintained substantially equal to a target value , which is modified periodically to account for core burnup. A neutron absorbing element within the core coolant, or moderator, is employed to assist control of reactivity changes associated with changes in power, with the full-length control rods mainly employed to adjust variations in the axial power distribution while the part-length rodsremain completely withdrawn from the fuel region of the core. Rapid changes in reactivity are implemented, to accommodate corresponding changes in load, by a controlled reduction of the core coolant temperature. Thus, active core coolant temperature control is employed to control the reactivity of the core during load follow operation and effectively increase the spinning reserve capability of a power plant without altering the axial power distribution.

  20. Bacteria in shear flow

    E-Print Network [OSTI]

    Marcos, Ph.D. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    Bacteria are ubiquitous and play a critical role in many contexts. Their environment is nearly always dynamic due to the prevalence of fluid flow: creeping flow in soil, highly sheared flow in bodily conduits, and turbulent ...

  1. Dispersed flow film boiling

    E-Print Network [OSTI]

    Yoder, Graydon L.

    1980-01-01T23:59:59.000Z

    Dispersed flow consists of small liquid droplets entrained in a flowing vapor. This flow regime can occur in cryogenic equipment, in steam generators, and during nuclear reactor loss of coolant accidents. A theoretical ...

  2. Multiphase flow calculation software

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2003-04-15T23:59:59.000Z

    Multiphase flow calculation software and computer-readable media carrying computer executable instructions for calculating liquid and gas phase mass flow rates of high void fraction multiphase flows. The multiphase flow calculation software employs various given, or experimentally determined, parameters in conjunction with a plurality of pressure differentials of a multiphase flow, preferably supplied by a differential pressure flowmeter or the like, to determine liquid and gas phase mass flow rates of the high void fraction multiphase flows. Embodiments of the multiphase flow calculation software are suitable for use in a variety of applications, including real-time management and control of an object system.

  3. Determination of the Axial-Vector Weak Coupling Constant with Ultracold Neutrons

    E-Print Network [OSTI]

    UCNA Collaboration; J. Liu; M. P. Mendenhall; A. T. Holley; H. O. Back; T. J. Bowles; L. J. Broussard; R. Carr; S. Clayton; S. Currie; B. W. Filippone; A. Garcia; P. Geltenbort; K. P. Hickerson; J. Hoagland; G. E. Hogan; B. Hona; T. M. Ito; C. -Y. Liu; M. Makela; R. R. Mammei; J. W. Martin; D. Melconian; C. L. Morris; R. W. Pattie Jr.; A. Perez Galvan; M. L. Pitt; B. Plaster; J. C. Ramsey; R. Rios; R. Russell; A. Saunders; S. J. Seestrom; W. E. Sondheim; E. Tatar; R. B. Vogelaar; B. VornDick; C. Wrede; H. Yan; A. R. Young

    2010-09-25T23:59:59.000Z

    A precise measurement of the neutron decay $\\beta$-asymmetry $A_0$ has been carried out using polarized ultracold neutrons (UCN) from the pulsed spallation UCN source at the Los Alamos Neutron Science Center (LANSCE). Combining data obtained in 2008 and 2009, we report $A_0 = -0.11966 \\pm 0.00089_{-0.00140}^{+0.00123}$, from which we determine the ratio of the axial-vector to vector weak coupling of the nucleon $g_A/g_V = -1.27590_{-0.00445}^{+0.00409}$.

  4. Determination of the Axial-Vector Weak Coupling Constant with Polarized Ultracold Neutrons

    E-Print Network [OSTI]

    Liu, J; Holley, A T; Back, H O; Bowles, T J; Broussard, L J; Carr, R; Clayton, S; Currie, S; Filippone, B W; Garcia, A; Geltenbort, P; Hickerson, K P; Hoagland, J; Hogan, G E; Hona, B; Ito, T M; Liu, C -Y; Makela, M; Mammei, R R; Martin, J W; Melconian, D; Morris, C L; Pattie, R W; Galvan, A Perez; Pitt, M L; Plaster, B; Ramsey, J C; Rios, R; Russell, R; Saunders, A; Seestrom, S; Sondheim, W E; Tatar, E; Vogelaar, R B; VornDick, B; Wrede, C; Yan, H; Young, A R

    2010-01-01T23:59:59.000Z

    A precise measurement of the neutron decay $\\beta$-asymmetry $A_0$ has been carried out using polarized ultracold neutrons (UCN) from the pulsed spallation UCN source at the Los Alamos Neutron Science Center (LANSCE). Combining data obtained in 2008 and 2009, we report $A_0 = -0.11966 \\pm 0.00089 _{-0.00140}^{+0.00123}$, from which we determine the ratio of the axial-vector to vector weak coupling of the nucleon $g_A/g_V = -1.27590 _{-0.00445}^{+0.00409}$.

  5. Spatiotemporal evolution of ponderomotive electron heating in axially inhomogeneous collisionless plasma

    SciTech Connect (OSTI)

    Mishra, S. K. [Institute for Plasma Research (IPR), Gandhinagar (India)] [Institute for Plasma Research (IPR), Gandhinagar (India); Sharma, A. [Institute of Physics, University of Pecs, Pecs 7624 (Hungary)] [Institute of Physics, University of Pecs, Pecs 7624 (Hungary)

    2013-07-15T23:59:59.000Z

    We investigate the spatiotemporal focusing dynamics of a Gaussian laser pulse in preformed collisionless plasma subjected to an axial nonuniformity in the plasma density. In order to follow up the pulse dynamics, a nonlinear Schrödinger wave equation characterizing the beam spot size in space and time frame has been derived and solved numerically to investigate the propagation characteristics as the pulse advances in the plasma. The effect of inhomogeneity on focusing length and ponderomotive electron heating have been analyzed and illustrated graphically. It is seen that ponderomotive heating is quite sensitive to the inhomogeneity parameters and the energy gain by electrons can be optimized by suitable choice of parameters.

  6. Axial force imparted by a conical radiofrequency magneto-plasma thruster

    SciTech Connect (OSTI)

    Charles, C.; Takahashi, K.; Boswell, R. W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, ACT 0200 (Australia)

    2012-03-12T23:59:59.000Z

    Direct thrust measurements of a low pressure ({approx}0.133 Pa) conical radiofrequency (rf at 13.56 MHz) argon plasma source show a total axial force of about 5 mN for an effective rf power of 650 W and a maximum magnetic field of 0.018 T, of which a measured value of 2.5 mN is imparted by the magnetic nozzle. A simplified model of thrust including contributions from the electron pressure and from the magnetic field pressure is developed. The magnetic nozzle is modelled as a ''physical'' nozzle of increasing cross-sectional area.

  7. Rotordynamic performance of a rotor supported on bump-type foil bearings: experiments and predictions

    E-Print Network [OSTI]

    Rubio Tabares, Dario

    2006-08-16T23:59:59.000Z

    Ww P L D= ? ? , Load coefficient Wn Bearing load [N] X, Y Horizontal and vertical rotor displacements xG Distance between the rotor CG to the free end [mm] z Damping ratio ? ( ) K E T t? = ? . FB dimensionless stiffness coefficient ? 26... length [mm] m Imbalance mass [kg] zm ? z z D ? = ? ?? , Total axial flow rate [kg/s] M, MB Rotor mass and bearing mass [kg] zM ? ( )2 23 24 s a z V g P PcM R T L ? ? = ? ? ? ? , Mass flow rate per bearing circumferential length [kg/m.s] N1...

  8. Fracture analysis of axially cracked pressure tube of pressurized heavy water reactor

    SciTech Connect (OSTI)

    Krishnan, S.; Bhasin, V.; Mahajan, S.C. [Bhabha Atomic Research Centre, Bombay (India)] [and others

    1997-04-01T23:59:59.000Z

    Three Dimensional (313) finite element elastic plastic fracture analysis was done for through wall axially cracked thin pressure tubes of 220 MWe Indian Pressurized Heavy Water Reactor. The analysis was done for Zr-2 and Zr-2.5Nb pressure tubes operating at 300{degrees}C and subjected to 9.5 Mpa internal pressure. Critical crack length was determined based on tearing instability concept. The analysis included the effect of crack face pressure due to the leaking fluid from tube. This effect was found to be significant for pressure tubes. The available formulae for calculating J (for axially cracked tubes) do not take into account the effect of crack face pressure. 3D finite element analysis also gives insight into variation of J across the thickness of pressure tube. It was observed that J is highest at the mid-surface of tube. The results have been presented in the form of across the thickness average J value and a peak factor on J. Peak factor on J is ratio of J at mid surface to average J value. Crack opening area for different cracked lengths was calculated from finite element results. The fracture assessment of pressure tubes was also done using Central Electricity Generating Board R-6 method. Ductile tearing was considered.

  9. Broken axial symmetry as essential feature to predict radiative capture in heavy nuclei

    E-Print Network [OSTI]

    Grosse, Eckart; Massarczyk, Ralph

    2014-01-01T23:59:59.000Z

    Cross sections for neutron capture in the range of unresolved resonances are predicted for more than 140 spin-0 target nuclei with A > 50. Allowing the breaking of spherical and axial symmetry in nearly all these nuclei a combined parameterization for both, level density and photon strength is obtained which employs a surprisingly small number of parameters only. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians. They are based on theoretical predictions for the A-dependence of pole energies and spreading widths and add up to the TRK sum rule. For the small spins reached by capture resonance spacings are well described by a level density parameter close to the nuclear matter value; a significant collective enhancement is apparent due to the deviation from axial symmetry. Reliable predictions for compound nuclear reactions also outside the valley of stability (as important for nuclear astrophysics and for the transmutation of nuclear waste) are expected to re...

  10. Broken axial symmetry as essential feature to predict radiative capture in heavy nuclei

    E-Print Network [OSTI]

    Eckart Grosse; Arnd R. Junghans; Ralph Massarczyk

    2015-01-14T23:59:59.000Z

    Cross sections for neutron capture in the range of unresolved resonances are predicted for more than 140 spin-0 target nuclei with A > 50. Allowing the breaking of spherical and axial symmetry in nearly all these nuclei a combined parameterization for both, level density and photon strength is obtained which employs a surprisingly small number of parameters only. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians. They are based on theoretical predictions for the A-dependence of pole energies and spreading widths and add up to the TRK sum rule. For the small spins reached by capture resonance spacings are well described by a level density parameter close to the nuclear matter value; a significant collective enhancement is apparent due to the deviation from axial symmetry. Reliable predictions for compound nuclear reactions also outside the valley of stability (as important for nuclear astrophysics and for the transmutation of nuclear waste) are expected to result from the global parameterization presented.

  11. A two-dimensional (azimuthal-axial) particle-in-cell model of a Hall thruster

    SciTech Connect (OSTI)

    Coche, P.; Garrigues, L., E-mail: laurent.garrigues@laplace.univ-tlse.fr [LAPLACE (Laboratoire Plasma et Conversion d'Energie), Université de Toulouse, UPS, INPT Toulouse 118, route de Narbonne, F-31062 Toulouse cedex 9 (France); CNRS, LAPLACE, F-31062 Toulouse (France)

    2014-02-15T23:59:59.000Z

    We have developed a two-dimensional Particle-In-Cell model in the azimuthal and axial directions of the Hall thruster. A scaling method that consists to work at a lower plasma density to overcome constraints on time-step and grid-spacing is used. Calculations are able to reproduce the breathing mode due to a periodic depletion of neutral atoms without the introduction of a supplementary anomalous mechanism, as in fluid and hybrid models. Results show that during the increase of the discharge current, an electron-cyclotron drift instability (frequency in the range of MHz and wave number on the order of 3000 rad s{sup ?1}) is formed in the region of the negative gradient of magnetic field. During the current decrease, an axial electric wave propagates from the channel toward the exhaust (whose frequency is on the order of 400?kHz) leading to a broadening of the ion energy distribution function. A discussion about the influence of the scaling method on the calculation results is also proposed.

  12. Measuring the axial form factor of {sup 3}He using weak capture of polarized electrons

    SciTech Connect (OSTI)

    Dutta, D. [Mississippi State University, Mississippi State, MS 39762 (United States)

    2013-11-07T23:59:59.000Z

    A low energy, high intensity polarized electron beam could enable the extraction of the A=3 weak axial form factors F{sub A} using the reaction ?e+{sup 3}He?{sup 3}H+?. These form factors have never been measured before. We discuss the feasibility of such an experiment using a small toroidal magnet and a radial low energy recoil detector to tag the recoil tritons. A moderately high intensity polarized electron beam (>500 ?A) with beam energies between 50 - 150 MeV is necessary for the cross section measurement and to provides a free clean measurement of the background. Moreover, in addition to the cross section, by measuring the electron spin and recoil triton correlation coefficient it may be possible to search for second class currents and to extract the ratio of the axial to the vector form factor of the nucleon. Such novel electron scattering based measurements would have a completely different set of systematic uncertainties compared to polarized neutron beta decay, neutrino scattering and muon capture experiments which are typically used to extract the weak form-factors.

  13. Clean measurements of the nucleon axial-vector and free-neutron magnetic form factors

    E-Print Network [OSTI]

    Alexandre Deur

    2014-07-21T23:59:59.000Z

    We discuss the feasibility of a weak charged current experiment using a low energy electron beam. A first goal is to measure the Q^2 dependence of the axial-vector form factor g_a(Q^2). It can be measured model-independently and as robustly as for electromagnetic form factors from typical electron scattering experiments, in contrast to the methods used so far to measure g_a(Q^2). If g_a(Q^2) follows a dipole form, the axial mass can be extracted with a better accuracy than the world data altogether. The most important detection equipment would be a segmented neutron detector with good momentum and angular resolution that is symmetric about the beam direction, and covers a moderate angular range. A high intensity beam (100 uA) is necessary. Beam polarization is highly desirable as it provides a clean measurement of the backgrounds. Beam energies between 70 and 110 MeV are ideal. This range would provide a Q^2 mapping of g_a between 0.01

  14. Freshwater Flow Charts - 1995

    SciTech Connect (OSTI)

    Kaiper, G V

    2003-11-21T23:59:59.000Z

    This report covers the following: (1) Explanation of Charts Showing Freshwater Flow in 1995; (2) Estimated U.S. Freshwater Flow in 1995 (chart); (3) Estimated California Freshwater Flow in 1995 (chart); (4) Estimated New Mexico Freshwater Flow in 1995 (chart); and (5) Web locations and credits.

  15. Energy of eigen-modes in magnetohydrodynamic flows of ideal fluids

    E-Print Network [OSTI]

    I. V. Khalzov; A. I. Smolyakov; V. I. Ilgisonis

    2007-12-11T23:59:59.000Z

    Analytical expression for energy of eigen-modes in magnetohydrodynamic flows of ideal fluids is obtained. It is shown that the energy of unstable modes is zero, while the energy of stable oscillatory modes (waves) can assume both positive and negative values. Negative energy waves always correspond to non-symmetric eigen-modes -- modes that have a component of wave-vector along the equilibrium velocity. These results suggest that all non-symmetric instabilities in ideal MHD systems with flows are associated with coupling of positive and negative energy waves. As an example the energy of eigen-modes is calculated for incompressible conducting fluid rotating in axial magnetic field.

  16. Portable wastewater flow meter

    DOE Patents [OSTI]

    Hunter, Robert M. (320 S. Wilson Ave., Bozeman, MT 59715)

    1990-01-01T23:59:59.000Z

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under full pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  17. Portable wastewater flow meter

    DOE Patents [OSTI]

    Hunter, Robert M. (320 S. Wilson Ave., Bozeman, MT 59715)

    1999-02-02T23:59:59.000Z

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under fill pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  18. Geometric solitons of Hamiltonian flows on manifolds

    SciTech Connect (OSTI)

    Song, Chong, E-mail: songchong@xmu.edu.cn [School of Mathematical Sciences, Xiamen University, Xiamen 361005 (China)] [School of Mathematical Sciences, Xiamen University, Xiamen 361005 (China); Sun, Xiaowei, E-mail: sunxw@cufe.edu.cn [School of Applied Mathematics, Central University of Finance and Economics, Beijing 100081 (China)] [School of Applied Mathematics, Central University of Finance and Economics, Beijing 100081 (China); Wang, Youde, E-mail: wyd@math.ac.cn [Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China)] [Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China)

    2013-12-15T23:59:59.000Z

    It is well-known that the LIE (Locally Induction Equation) admit soliton-type solutions and same soliton solutions arise from different and apparently irrelevant physical models. By comparing the solitons of LIE and Killing magnetic geodesics, we observe that these solitons are essentially decided by two families of isometries of the domain and the target space, respectively. With this insight, we propose the new concept of geometric solitons of Hamiltonian flows on manifolds, such as geometric Schrödinger flows and KdV flows for maps. Moreover, we give several examples of geometric solitons of the Schrödinger flow and geometric KdV flow, including magnetic curves as geometric Schrödinger solitons and explicit geometric KdV solitons on surfaces of revolution.

  19. Measurement of the forming limit stress curve using a multi-axial tube expansion test with a digital image correlation system

    SciTech Connect (OSTI)

    Hakoyama, Tomoyuki [Department of Mechanical Systems Engineering, Graduate school of Engineering, Tokyo University of Agriculture and Technology, 2-24-16, Nakacho, Koganei-shi, Tokyo, 184-8588 (Japan); Kuwabara, Toshihiko [Division of Advanced Mechanical Systems Engineering, Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16, Nakacho, Koganei-shi, Tokyo, 184-8588 (Japan)

    2013-12-16T23:59:59.000Z

    A servo-controlled tension-internal pressure testing machine with an optical 3D deformation analysis system (ARAMIS) was used to measure the multi-axial plastic deformation behavior of a high-strength steel sheet for a range of strain from initial yield to fracture. The testing machine is capable of applying arbitrary principal stress or strain paths to a tubular specimen using an electrical, closed-loop servo-control system for axial force and internal pressure. Tubular specimens with an inner diameter of 44.6 mm were fabricated from a high-strength steel sheet with a tensile strength of 590 MPa and a thickness of 1.2 mm by roller bending and laser welding. Several linear and non-linear stress paths in the first quadrant of the stress space were applied to the tubular specimens in order to measure the forming limit curve (FLC) and forming limit stress curve (FLSC) of the as-received test material, in addition to the contours of plastic work and the directions of plastic strain rates. The contours of plastic work and the directions of plastic strain rates measured for the linear stress path experiments were compared with those calculated using selected yield functions in order to identify the most appropriate yield function for the test material. Moreover, a Marciniak-Kuczy?ski type (M-K) forming limit analysis was performed using the most appropriate yield function. The calculated and measured FLC and FLSC were compared in order to validate the M-K approach. The path-dependence of the FLC and FLSC was also investigated.

  20. Natural Circulation and Linear Stability Analysis for Liquid-Metal Reactors with the Effect of Fluid Axial Conduction

    SciTech Connect (OSTI)

    Piyush Sabharwall; Qiao Wu; James J. Sienicki

    2012-06-01T23:59:59.000Z

    The effect of fluid axial thermal conduction on one-dimensional liquid metal natural circulation and its linear stability was performed through nondimensional analysis, steady-state assessment, and linear perturbation evaluation. The Nyquist criterion and a root-search method were employed to find the linear stability boundary of both forward and backward circulations. The study provided a relatively complete analysis method for one-dimensional natural circulation problems with the consideration of fluid axial heat conduction. The results suggest that fluid axial heat conduction in a natural circulation loop should be considered only when the modified Peclet number is {approx}1 or less, which is significantly smaller than the practical value of a lead liquid metal-cooled reactor.

  1. Nucleon and Delta axial-vector couplings in 1/N{sub c}-Baryon Chiral Perturbation Theory

    SciTech Connect (OSTI)

    Goity, Jose Luis [JLAB; Calle Cordon, Alvaro [JLAB

    2013-08-01T23:59:59.000Z

    In this contribution, baryon axial-vector couplings are studied in the framework of the combined 1/N{sub c} and chiral expansions. This framework is implemented on the basis of the emergent spin-flavor symmetry in baryons at large N{sub c} and HBChPT, and linking both expansions ({xi}-expansion), where 1/N{sub c} is taken to be a quantity order p. The study is carried out including one-loop contributions, which corresponds to order xi to the third for baryon masses and order {xi} square for the axial couplings.

  2. Microwave electron cyclotron electron resonance (ECR) ion source with a large, uniformly distributed, axially symmetric, ECR plasma volume

    DOE Patents [OSTI]

    Alton, Gerald D. (Kingston, TN)

    1996-01-01T23:59:59.000Z

    An electron cyclotron resonance (ECR) ion source includes a primary mirror coil disposed coaxially around a vacuum vessel in which a plasma is induced and introducing a solenoidal ECR-producing field throughout the length of the vacuum vessel. Radial plasma confinement is provided by a multi-cusp, multi-polar permanent magnet array disposed azimuthally around the vessel and within the primary mirror coil. Axial confinement is provided either by multi-cusp permanent magnets at the opposite axial ends of the vessel, or by secondary mirror coils disposed on opposite sides of the primary coil.

  3. Failure probability of axially cracked steam generator tubes; A probabilistic fracture mechanics model

    SciTech Connect (OSTI)

    Mavko, B.; Cizelj, L. (Jozef Stefan Inst., Reactor Engineering Div., P.O. Box 100, 61111 Ljubljana, Slovenia (YU))

    1992-05-01T23:59:59.000Z

    In this paper a model for estimating the failure probability of axially cracked steam generator tubes is proposed. The model compares observed crack length distribution with critical crack length distribution by means of probabilistic fracture mechanics. The observed crack length is influenced by measured data, measurement reliability, sizing accuracy, and predicted crack growth rate. The critical crack length is defined by a deterministic mechanical model. All cracks are conservatively assumed to extend through the tube wall. The effect of the plugging limit is studied along with the number of cracked tubes to perform risk-based lifetime optimization of steam generators. A numerical example presented considers hypothetical accidental operating conditions during a feedwater line break.

  4. A magnetic liquid deformable mirror for high stroke and low order axially symmetrical aberrations

    E-Print Network [OSTI]

    Brousseau, D; Parent, J; Ruel, H J; Borra, Ermanno F.; Brousseau, Denis; Parent, Jocelyn; Ruel, Hubert-Jean

    2006-01-01T23:59:59.000Z

    We present a new class of magnetically shaped deformable liquid mirrors made of a magnetic liquid (ferrofluid). Deformable liquid mirrors offer advantages with respect to deformable solid mirrors: large deformations, low costs and the possibility of very large mirrors with added aberration control. They have some disadvantages (e.g. slower response time). We made and tested a deformable mirror, producing axially symmetrical wavefront aberrations by applying electric currents to 5 concentric coils made of copper wire wound on aluminum cylinders. Each of these coils generates a magnetic field which combines to deform the surface of a ferrofluid to the desired shape. We have carried out laboratory tests on a 5 cm diameter prototype mirror and demonstrated defocus as well as Seidel and Zernike spherical aberrations having amplitudes up to 20 microns, which was the limiting measurable amplitude of our equipment

  5. A magnetic liquid deformable mirror for high stroke and low order axially symmetrical aberrations

    E-Print Network [OSTI]

    Denis Brousseau; Ermanno F. Borra; Hubert-Jean Ruel; Jocelyn Parent

    2006-11-15T23:59:59.000Z

    We present a new class of magnetically shaped deformable liquid mirrors made of a magnetic liquid (ferrofluid). Deformable liquid mirrors offer advantages with respect to deformable solid mirrors: large deformations, low costs and the possibility of very large mirrors with added aberration control. They have some disadvantages (e.g. slower response time). We made and tested a deformable mirror, producing axially symmetrical wavefront aberrations by applying electric currents to 5 concentric coils made of copper wire wound on aluminum cylinders. Each of these coils generates a magnetic field which combines to deform the surface of a ferrofluid to the desired shape. We have carried out laboratory tests on a 5 cm diameter prototype mirror and demonstrated defocus as well as Seidel and Zernike spherical aberrations having amplitudes up to 20 microns, which was the limiting measurable amplitude of our equipment

  6. Exponential Decay of Eigenfunctions and Accumulation of Eigenvalues on Manifolds with Axial Analytic Asymptotically Cylindrical Ends

    E-Print Network [OSTI]

    Victor Kalvin

    2010-07-25T23:59:59.000Z

    In this paper we continue our study of the Laplacian on manifolds with axial analytic asymptotically cylindrical ends initiated in~arXiv:1003.2538. By using the complex scaling method and the Phragm\\'{e}n-Lindel\\"{o}f principle we prove exponential decay of the eigenfunctions corresponding to the non-threshold eigenvalues of the Laplacian on functions. In the case of a manifold with (non-compact) boundary it is either the Dirichlet Laplacian or the Neumann Laplacian. We show that the rate of exponential decay of an eigenfunction is prescribed by the distance from the corresponding eigenvalue to the next threshold. Under our assumptions on the behaviour of the metric at infinity accumulation of isolated and embedded eigenvalues occur. The results on decay of eigenfunctions combined with the compactness argument due to Perry imply that the eigenvalues can accumulate only at thresholds and only from below. The eigenvalues are of finite multiplicity.

  7. Axial strain in GaAs/InAs core-shell nanowires

    SciTech Connect (OSTI)

    Biermanns, Andreas; Pietsch, Ullrich [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany)] [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany); Rieger, Torsten; Gruetzmacher, Detlev; Ion Lepsa, Mihail [Peter Gruenberg Institute (PGI-9), Forschungszentrum, 52425 Juelich (Germany) [Peter Gruenberg Institute (PGI-9), Forschungszentrum, 52425 Juelich (Germany); JARA-Fundamentals of Future Information Technology, 52425 Juelich (Germany); Bussone, Genziana [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany) [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany); ESRF, 6 rue Jules Horowitz, BP220, F-38043 Grenoble Cedex (France)

    2013-01-28T23:59:59.000Z

    We study the axial strain relaxation in GaAs/InAs core-shell nanowire heterostructures grown by molecular beam epitaxy. Besides a gradual strain relaxation of the shell material, we find a significant strain in the GaAs core, increasing with shell thickness. This strain is explained by a saturation of the dislocation density at the core-shell interface. Independent measurements of core and shell lattice parameters by x-ray diffraction reveal a relaxation of 93% in a 35 nm thick InAs shell surrounding cores of 80 nm diameter. The compressive strain of -0.5% compared to bulk InAs is accompanied by a tensile strain up to 0.9% in the GaAs core.

  8. Hamiltonian dynamics of a symmetric top in external fields having axial symmetry. Levitating Orbitron

    E-Print Network [OSTI]

    Stanislav S. Zub; Sergiy I. Zub

    2015-02-13T23:59:59.000Z

    The symmetric top is a special case of the general top, and canonical Poisson structure on $T^*SE(3)$ is the common method of its description. This structure is invariant under the right action of $SO(3)$, but the Hamiltonian of the symmetric top is invariant only under the right action of subgroup $S^1$ that corresponds to the rotation around the symmetry axis of the symmetric top. So, its Poisson structure was obtained as the reduction $T^*SE(3)/S^1$. Next we propose the Hamiltonian that describes the wide class of the interaction models of symmetric top and axially-symmetric external field. The stability of the levitating Orbitron in relative equilibrium was proved.

  9. First-Forbidden beta decay Medium enhancement of the axial charge at A=16

    E-Print Network [OSTI]

    Warburton, E K; Brown, B A

    1994-01-01T23:59:59.000Z

    Calculations are presented for four relatively strong first-forbidden $\\beta$ decays in the region A=11-16 in order to study the very large mesonic-exchange-current enhancement of the rank-zero components. The $\\mu^-$ capture on $^{16}$O is considered on the same footing. The wave functions utilized include up to 4$\\hbar\\omega$ excitations. Two-body exchange-current matrix elements are calculated as well as one-body impulse approximation matrix elements. The resultant enhancement factor that multiplies the impulse-approximation axial-charge matrix element is thereby determined by comparison to experiment to be $\\epsilon_{exp}$ = 1.61 $\\pm$ 0.03 from three $\\beta^-$ decays and $\\mu^-$ capture on $^{16}$O, which is in excellent agreement with meson-exchange calculations in the soft-pion approximation.

  10. WIMP identification through a combined measurement of axial and scalar couplings

    E-Print Network [OSTI]

    Bertone, G; Collar, J I; Odom, B

    2007-01-01T23:59:59.000Z

    We study the prospects for detecting Weakly Interacting Massive Particles (WIMPs), in a number of phenomenological scenarios, with a detector composed of a target simultaneously sensitive to both spin-dependent and spin-independent couplings, as is the case of COUPP (Chicagoland Observatory for Underground Particle Physics). First, we show that sensitivity to both couplings optimizes chances of initial WIMP detection. Second, we demonstrate that in case of detection, comparison of the signal on two complementary targets, such as in COUPP CF3I and C4F10 bubble chambers, allows a significantly more precise determination of the dark matter axial and scalar couplings. This strategy would provide crucial information on the nature of the WIMPs, and possibly allow discrimination between neutralino and Kaluza-Klein dark matter.

  11. WIMP identification through a combined measurement of axial and scalar couplings

    E-Print Network [OSTI]

    G. Bertone; D. G. Cerdeno; J. I. Collar; B. Odom

    2007-07-23T23:59:59.000Z

    We study the prospects for detecting Weakly Interacting Massive Particles (WIMPs), in a number of phenomenological scenarios, with a detector composed of a target simultaneously sensitive to both spin-dependent and spin-independent couplings, as is the case of COUPP (Chicagoland Observatory for Underground Particle Physics). First, we show that sensitivity to both couplings optimizes chances of initial WIMP detection. Second, we demonstrate that in case of detection, comparison of the signal on two complementary targets, such as in COUPP CF3I and C4F10 bubble chambers, allows a significantly more precise determination of the dark matter axial and scalar couplings. This strategy would provide crucial information on the nature of the WIMPs, and possibly allow discrimination between neutralino and Kaluza-Klein dark matter.

  12. Cyclic powder formation during pulsed injection of hexamethyldisiloxane in an axially asymmetric radiofrequency argon discharge

    SciTech Connect (OSTI)

    Despax, B.; Makasheva, K. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse 09 (France); CNRS, LAPLACE, F-31062 Toulouse cedex 09 (France); Caquineau, H. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse 09 (France)

    2012-11-01T23:59:59.000Z

    A new approach of periodic production of dusty plasma consisting of pulsed injection of hexamethyldisiloxane (HMDSO) in argon axially asymmetric radiofrequency (RF) discharge was investigated in this work. The range of plasma operating conditions in which this dusty plasma can exist was closely examined. The obtained results clearly show that a net periodicity in the formation/disappearance of dust particles in the plasma can be maintained on a very large scale of discharge duration. The significance of discharge axial asymmetry to the dust particles behaviour in the plasma is revealed by the development of an asymmetric in shape void shifted towards the powered RF electrode. The key role of the reactive gas and its pulsed injection on each stage of the oscillating process of formation/disappearance of dust particles is disclosed by optical and electrical measurements. It is shown that the period of dusty plasma formation/disappearance is inversely related to the HMDSO injection time. Moreover, the impact of time injection over short period (5 s) is examined. It indicates the conflicting role played by the HMDSO on the reduction of dusty plasma during the reactive gas injection and the reappearance of particles in the plasma during the time off. The electronegative behavior of the plasma in the presence of negatively charged particles seems to explain the energetic modifications in the discharge. A frequency analysis of the floating potential reveals all these cyclic processes. Particularly, in the 10-200 Hz frequency range, the presence and the evolution of dust particles in the plasma over one generation can be observed.

  13. Isospin-invariant Skyrme energy-density-functional approach with axial symmetry

    E-Print Network [OSTI]

    J. A. Sheikh; N. Hinohara; J. Dobaczewski; T. Nakatsukasa; W. Nazarewicz; K. Sato

    2014-05-20T23:59:59.000Z

    We develop the isospin-invariant Skyrme-EDF method by considering local densities in all possible isospin channels and proton-neutron (p-n) mixing terms as mandated by the isospin symmetry. The EDF employed has the most general form that depends quadratically on the isoscalar and isovector densities. We test and benchmark the resulting p-n EDF approach, and study the general properties of the new scheme by means of the cranking in the isospin space. We extend the existing axial DFT solver HFBTHO to the case of isospin-invariant EDF approach with all possible p-n mixing terms. Explicit expressions have been derived for all the densities and potentials that appear in the isospin representation. In practical tests, we consider the Skyrme EDF SkM* and, as a first application, concentrate on Hartree-Fock aspects of the problem, i.e., pairing has been disregarded. Calculations have been performed for the (A=78, T~11), (A=40, T~8), and (A=48, T~4) isobaric analog chains. Isospin structure of self-consistent p-n mixed solutions has been investigated with and without the Coulomb interaction, which is the sole source of isospin symmetry breaking in our approach. The extended axial HFBTHO solver has been benchmarked against the symmetry-unrestricted HFODD code for deformed and spherical states. We developed and tested a general isospin-invariant Skyrme-EDF framework. The new approach permits spin-isospin densities that may give rise to, hitherto, unexplored modes in the excitation spectrum. The new formalism has been tested in the Hartree-Fock limit. A systematic comparison between HFODD and HFBTHO results show a maximum deviation of about 10 keV on the total binding energy for deformed nuclei when the Coulomb term is included. Without this term, the results of both solvers agree down to a ~10 eV level.

  14. Current scaling of axially radiated power in dynamic hohlraums and dynamic hohlraum load design for ZR.

    SciTech Connect (OSTI)

    Mock, Raymond Cecil; Nash, Thomas J.; Sanford, Thomas W. L.

    2007-03-01T23:59:59.000Z

    We present designs for dynamic hohlraum z-pinch loads on the 28 MA, 140 ns driver ZR. The scaling of axially radiated power with current in dynamic hohlraums is reviewed. With adequate stability on ZR this scaling indicates that 30 TW of axially radiated power should be possible. The performance of the dynamic hohlraum load on the 20 MA, 100 ns driver Z is extensively reviewed. The baseline z-pinch load on Z is a nested tungsten wire array imploding onto on-axis foam. Data from a variety of x-ray diagnostics fielded on Z are presented. These diagnostics include x-ray diodes, bolometers, fast x-ray imaging cameras, and crystal spectrometers. Analysis of these data indicates that the peak dynamic radiation temperature on Z is between 250 and 300 eV from a diameter less than 1 mm. Radiation from the dynamic hohlraum itself or from a radiatively driven pellet within the dynamic hohlraum has been used to probe a variety of matter associated with the dynamic hohlraum: the tungsten z-pinch itself, tungsten sliding across the end-on apertures, a titanium foil over the end aperture, and a silicon aerogel end cap. Data showing the existence of asymmetry in radiation emanating from the two ends of the dynamic hohlraum is presented, along with data showing load configurations that mitigate this asymmetry. 1D simulations of the dynamic hohlraum implosion are presented and compared to experimental data. The simulations provide insight into the dynamic hohlraum behavior but are not necessarily a reliable design tool because of the inherently 3D behavior of the imploding nested tungsten wire arrays.

  15. Assignment Types UTS LIBRARY

    E-Print Network [OSTI]

    University of Technology, Sydney

    Assignment Types UTS LIBRARY February 2013 Academic Writing Guide Part 2 ­ Assignment Types: This section outlines the basic types of written assignments, providing structural elements and examples. #12;2 II. Assignment Types 1. Essay Writing

  16. Zonal Flow as Pattern Formation

    E-Print Network [OSTI]

    Parker, Jeffrey B

    2015-01-01T23:59:59.000Z

    In this section, we examine the transition from statistically homogeneous turbulence to inhomogeneous turbulence with zonal flows. Statistical equations of motion can be derived from the quasilinear approximation to the Hasegawa-Mima equation. We review recent work that finds a bifurcation of these equations and shows that the emergence of zonal flows mathematically follows a standard type of pattern formation. We also show that the dispersion relation of modulational instability can be extracted from the statistical equations of motion in a certain limit. The statistical formulation can thus be thought to offer a more general perspective on growth of coherent structures, namely through instability of a full turbulent spectrum. Finally, we offer a physical perspective on the growth of large-scale structures.

  17. A finite element model of the turbulent flow field in a centrifugal impeller

    E-Print Network [OSTI]

    Hlavaty, Steven Todd

    1993-01-01T23:59:59.000Z

    , or for applications such as pumps utilizing a liquid as the working medium. Full ellipticity of the flow- governing equations throughout the computational domain is rigorously retained. As a result, the model is conceptually capable of predicting real-flow effects... such as flow separation and recirculation, regardless of whether such complex flow behavior is local or massive. Applicability of the model is illustrated using a typical pump impeller of the purely centrifugal type. In presenting the computed flow field...

  18. Ultrasonic flow metering system

    DOE Patents [OSTI]

    Gomm, Tyler J. (Meridian, ID); Kraft, Nancy C. (Idaho Falls, ID); Mauseth, Jason A. (Pocatello, ID); Phelps, Larry D. (Pocatello, ID); Taylor, Steven C. (Idaho Falls, ID)

    2002-01-01T23:59:59.000Z

    A system for determining the density, flow velocity, and mass flow of a fluid comprising at least one sing-around circuit that determines the velocity of a signal in the fluid and that is correlatable to a database for the fluid. A system for determining flow velocity uses two of the inventive circuits with directional transmitters and receivers, one of which is set at an angle to the direction of flow that is different from the others.

  19. Modeling of Seismic Signatures of Carbonate Rock Types 

    E-Print Network [OSTI]

    Jan, Badr H.

    2011-02-22T23:59:59.000Z

    Carbonate reservoirs of different rock types have wide ranges of porosity and permeability, creating zones with different reservoir quality and flow properties. This research addresses how seismic technology can be used ...

  20. Modeling of Seismic Signatures of Carbonate Rock Types

    E-Print Network [OSTI]

    Jan, Badr H.

    2011-02-22T23:59:59.000Z

    Carbonate reservoirs of different rock types have wide ranges of porosity and permeability, creating zones with different reservoir quality and flow properties. This research addresses how seismic technology can be used to identify different...

  1. Supplemental Material for Severson et al. The axial element protein HTP-3 promotes cohesin loading and meiotic axis

    E-Print Network [OSTI]

    Meyer, Barbara

    Supplemental Material for Severson et al. The axial element protein HTP-3 promotes cohesin loading ......................................................................................... 7 Disrupting REC-8, HTP-3, or HTP-1/2 function reduces the lethality of spo-11(me44) mutants ....................................................................................... 13 The htp-3 deletion allele tm3655 phenocopies htp-3(y428). Supplemental Figure 8

  2. Path-integral solution for a two-dimensional model with axial-vector-current--pseudoscalar derivative interaction

    SciTech Connect (OSTI)

    Botelho, L.C.L.

    1985-03-15T23:59:59.000Z

    We study a two-dimensional quantum field model with axial-vector-current--pseudoscalar derivative interaction using path-integral methods. We construct an effective Lagrangian by performing a chiral change in the fermionic variables leading to an exact solution of the model.

  3. The effect of axial strain cycling on the critical current density and n-value of ITER niobium-tin

    E-Print Network [OSTI]

    Hampshire, Damian

    The effect of axial strain cycling on the critical current density and n-value of ITER niobium niobium-tin VAC and EM-LMI strands and the detailed characterisation of the EM-LMI-TFMC strand at -0 current density and n-value of two ITER candidate niobium-tin strands (EM- LMI and VAC). The strands were

  4. Identification of spin wave modes in yttrium iron garnet strongly coupled to a co-axial cavity.

    E-Print Network [OSTI]

    Lambert, N. J.; Haigh, J. A.; Ferguson, A. J.

    2015-02-05T23:59:59.000Z

    AIP/123-QED Identification of spin wave modes in yttrium iron garnet strongly coupled to a co-axial cavity. N. J. Lambert,1 J. A. Haigh,2 and A. J. Ferguson1 1)Microelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE...

  5. Radial Inflow Gas Turbine Flow Path Design

    E-Print Network [OSTI]

    Samip Shah; Gaurang Chaudhri; Digvijay Kulshreshtha; S. A. Channiwalla

    Abstract:- A new method for radial inflow gas turbine flow paths design based on a unique integrated conceptual design environment AxSTREAM is presented in this paper. This integrated environment is a seamless and swift processing scheme that incorporates stages aerodynamic analysis and preliminary design/sizing based on the one dimensional method. The environment makes possible to find number of different designs with inverse task solver, basing on initially specified boundary conditions, closing conditions and design variables. Design space explorer provides easy and visual comparison for range of obtained design in customizable coordinate axes. Solution filtering on different parameters, such as meridional and axial dimensions, maximal blades weight, saving the time to choose from thousands obtained solutions the only one right design. Flexibility of presented approach allows to built-up complete gas turbine flow path from consequence of individual elements: stationary and rotating elements, ducts, heat exchangers, and analyze it in common environment. Complete control of all aspects of aerodynamic flow path quality, structural reliability, and integral performances on design and offdesign conditions is performing throughout all design process. This gives full interaction between user and system for immediate correction and enhancement of current design data using various optimization capabilities to feel the impact of changes on each design step. Integrated system AxSTREAM significantly shortening the design cycle time from initial machine concept to finalized design with all offdesign performances details. The design process is demonstrated for a 25kW radial inflow gas turbine. Keywords:- Radial Inflow Turbine, Performance Maps, AxSTREAM I.

  6. Restricting information flow in security APIs via typing 

    E-Print Network [OSTI]

    Keighren, Gavin

    2014-06-27T23:59:59.000Z

    Security APIs are designed to enable the storage and processing of confidential data without that data becoming known to individuals who are not permitted to obtain it, and are central to the operation of Automated Teller ...

  7. Air Flow Distribution in the Sales Area of a Supermarket

    E-Print Network [OSTI]

    Fang, X.; Song, C.; Zhao, J.; Wang, Z.

    2006-01-01T23:59:59.000Z

    Many kinds of goods are displayed in a supermarket, which have their own particularities. The consumer flow rate is great and the type of shelved goods varies significantly, thereby influencing the objects that generate heat, and the demands of air...

  8. A tactical planning model for a serial flow manufacturing system

    E-Print Network [OSTI]

    Huang, Bin, S.M. Massachusetts Institute of Technology

    2010-01-01T23:59:59.000Z

    This project aims to improve the operation and planning of a specific type of manufacturing system, a serial flow line that entails a sequence of process stages. The objective is to investigate inventory policy, raw material ...

  9. Nonlinear springs with applications to flow regulation valves and mechanisms

    E-Print Network [OSTI]

    Freeman, David Calvin

    2008-01-01T23:59:59.000Z

    This thesis focuses on the application of nonlinear springs for fluid flow control valves where geometric constraints, or fabrication technologies, limit the use of available solutions. Types of existing nonlinear springs ...

  10. MODELING BLOOD FLOW IN THE CARDIOVASCULAR

    E-Print Network [OSTI]

    Olufsen, Mette Sofie

    MODELING BLOOD FLOW IN THE CARDIOVASCULAR SYSTEM MA432 ­ Spring 2013 Department of Mathematics (Greek),...; Two distinct types of blood were thought to exist: § "Nutritive blood" was thought to be made by the liver and carried through veins to the organs, where it was consumed § "Vital blood

  11. MODELING BLOOD FLOW IN THE CARDIOVASCULAR

    E-Print Network [OSTI]

    Olufsen, Mette Sofie

    MODELING BLOOD FLOW IN THE CARDIOVASCULAR SYSTEM MA325 ­ Spring 2013 Department of Mathematics (Greek),...; Two distinct types of blood were thought to exist: § Nutritive blood was thought to be made by the liver and carried through veins to the organs, where it was consumed § Vital blood was thought

  12. Dynamic pulse buckling of cylindrical shells under axial impact: A comparison of 2D and 3D finite element calculations with experimental data

    SciTech Connect (OSTI)

    Hoffman, E.L.; Ammerman, D.J.

    1995-04-01T23:59:59.000Z

    A series of tests investigating dynamic pulse buckling of a cylindrical shell under axial impact is compared to several 2D and 3D finite element simulations of the event. The purpose of the work is to investigate the performance of various analysis codes and element types on a problem which is applicable to radioactive material transport packages, and ultimately to develop a benchmark problem to qualify finite element analysis codes for the transport package design industry. Four axial impact tests were performed on 4 in-diameter, 8 in-long, 304 L stainless steel cylinders with a 3/16 in wall thickness. The cylinders were struck by a 597 lb mass with an impact velocity ranging from 42.2 to 45.1 ft/sec. During the impact event, a buckle formed at each end of the cylinder, and one of the two buckles became unstable and collapsed. The instability occurred at the top of the cylinder in three tests and at the bottom in one test. Numerical simulations of the test were performed using the following codes and element types: PRONTO2D with axisymmetric four-node quadrilaterals; PRONTO3D with both four-node shells and eight-node hexahedrons; and ABAQUS/Explicit with axisymmetric two-node shells and four-node quadrilaterals, and 3D four-node shells and eight-node hexahedrons. All of the calculations are compared to the tests with respect to deformed shape and impact load history. As in the tests, the location of the instability is not consistent in all of the calculations. However, the calculations show good agreement with impact load measurements with the exception of an initial load spike which is proven to be the dynamic response of the load cell to the impact. Finally, the PRONIT02D calculation is compared to the tests with respect to strain and acceleration histories. Accelerometer data exhibited good qualitative agreement with the calculations. The strain comparisons show that measurements are very sensitive to gage placement.

  13. US energy flow - 1984

    SciTech Connect (OSTI)

    Briggs, C.K.; Borg, I.Y.

    1985-07-01T23:59:59.000Z

    The 1984 energy flow diagram for the USA has been constructed using Department of Energy data. It is a convenient graphical device to show supply and demand as well as the size of end-use sectors. A 4% increase in overall energy consumption represented a reversal in a downward trend started in 1979. All indicators pointed to more healthy industrial and farm economies in 1984 than in the previous two years, which accounted for some part of the increase in energy use. While domestic crude oil production remained stable, oil imports rose eight percent also reversing a long-standing trend. Seventy-two million barrels of oil primarily from Mexico and the United Kingdom were added to the Strategic Petroleum Reserve bringing the total oil stored at year end to 451 million barrels. At the same time 49 million barrels of oil were produced from the government-owned Naval Petroleum Reserve No. 1 (Elk Hills, CA). Energy use in all end-use sectors grew in 1984 which is in keeping with increases in use of all types of fossil fuels as well as electricity. Increase in electrical power demand continued to exceed forecasts, and during 1984 contracts for imports to the northeast US were negotiated with Canada. Nuclear power contributed 15% of total power generated in the US. At year end there were 86 licensed reactors and 44 in either start-up or construction stages. Six were canceled or abandoned during construction during the year. 11 refs., 4 figs., 3 tabs.

  14. ON THE SIMULATION OF MULTICOMPONENT GAS FLOW IN POROUS MEDIA

    E-Print Network [OSTI]

    Ewing, Richard E.

    quadrilaterals as a solver to the non­Darcy flow equation, and a conservative Godunov­type scheme for the mass. Traditionally, the standard Darcy equation provides this relation. In this paper, however, we replace this classical law with the Forchheimer equation to model non­Darcy flow [9, 17, 13]. The mathematical nature

  15. Magnetic Amplifier for Power Flow Control

    SciTech Connect (OSTI)

    None

    2012-02-24T23:59:59.000Z

    GENI Project: ORNL is developing an electromagnet-based, amplifier-like device that will allow for complete control over the flow of power within the electric grid. To date, complete control of power flow within the grid has been prohibitively expensive. ORNL’s controller could provide a reliable, cost-effective solution to this problem. The team is combining two types of pre-existing technologies to assist in flow control, culminating in a prototype iron-based magnetic amplifier. Ordinarily, such a device would require expensive superconductive wire, but the magnetic iron core of ORNL’s device could serve as a low-cost alternative that is equally adept at regulating power flow.

  16. Smoothness monitors for compressible flow computation

    SciTech Connect (OSTI)

    Sjogreen, B; Yee, H C

    2008-09-02T23:59:59.000Z

    In [SY04, YS07] and references cited therein, the authors introduced the concept of employing multiresolution wavelet decomposition of computed flow data as smoothness monitors (flow sensors) to indicate the amount and location of built-in numerical dissipation that can be eliminated or further reduced in shock-capturing schemes. Studies indicated that this approach is able to limit the use of numerical dissipation with improved accuracy compared with standard shock-capturing methods. The studies in [SY04, YS07] were limited to low order multiresolution redundant wavelets with low level supports and low order vanishing moments. The objective of this paper is to expand the previous investigation to include higher order redundant wavelets with larger support and higher order vanishing moments for a wider spectrum of flow type and flow speed applications.

  17. Historical river flow rates for dose calculations

    SciTech Connect (OSTI)

    Carlton, W.H.

    1991-06-10T23:59:59.000Z

    Annual average river flow rates are required input to the LADTAP Computer Code for calculating offsite doses from liquid releases of radioactive materials to the Savannah River. The source of information on annual river flow rates used in dose calculations varies, depending on whether calculations are for retrospective releases or prospective releases. Examples of these types of releases are: Retrospective - releases from routine operations (annual environmental reports) and short term release incidents that have occurred. Prospective - releases that might be expected in the future from routine or abnormal operation of existing or new facilities (EIS`s, EID`S, SAR`S, etc.). This memorandum provides historical flow rates at the downstream gauging station at Highway 301 for use in retrospective dose calculations and derives flow rate data for the Beaufort-Jasper and Port Wentworth water treatment plants.

  18. Types of Costs Types of Cost Estimates

    E-Print Network [OSTI]

    Boisvert, Jeff

    · Types of Costs · Types of Cost Estimates · Methods to estimate capital costs MIN E 408: Mining% accuracy. ­ 2-5% of pre-production capital Types of Cost Estimates #12;3. Definitive ­ Based on definitive-even $ Production Level Fixed Cost Break-even $ Production Level Cost-Revenue Relationships · Capital Costs (or

  19. A New Type of Resonant Neutrino Conversions Induced by Magnetic Fields

    E-Print Network [OSTI]

    S. Sahu; V. B. Semikoz; J. W. F. Valle

    1995-12-21T23:59:59.000Z

    We consider resonant neutrino conversions in magnetised matter, such as a degenerate electron gas. We show how magnetisation effects caused by axial vector interactions of neutrinos with the charged leptons in the medium can induce a new type of resonant neutrino conversion which may occur even in situations where the MSW effect does not occur, such as the case of degenerate or inverted neutrino mass spectra. Our new resonance may simultaneously affect anti-neutrino $\\bar{\

  20. Lateral flow strip assay

    DOE Patents [OSTI]

    Miles, Robin R. (Danville, CA); Benett, William J. (Livermore, CA); Coleman, Matthew A. (Oakland, CA); Pearson, Francesca S. (Livermore, CA); Nasarabadi, Shanavaz L. (Livermore, CA)

    2011-03-08T23:59:59.000Z

    A lateral flow strip assay apparatus comprising a housing; a lateral flow strip in the housing, the lateral flow strip having a receiving portion; a sample collection unit; and a reagent reservoir. Saliva and/or buccal cells are collected from an individual using the sample collection unit. The sample collection unit is immersed in the reagent reservoir. The tip of the lateral flow strip is immersed in the reservoir and the reagent/sample mixture wicks up into the lateral flow strip to perform the assay.

  1. Radiant energy receiver having improved coolant flow control means

    DOE Patents [OSTI]

    Hinterberger, H.

    1980-10-29T23:59:59.000Z

    An improved coolant flow control for use in radiant energy receivers of the type having parallel flow paths is disclosed. A coolant performs as a temperature dependent valve means, increasing flow in the warmer flow paths of the receiver, and impeding flow in the cooler paths of the receiver. The coolant has a negative temperature coefficient of viscosity which is high enough such that only an insignificant flow through the receiver is experienced at the minimum operating temperature of the receiver, and such that a maximum flow is experienced at the maximum operating temperature of the receiver. The valving is accomplished by changes in viscosity of the coolant in response to the coolant being heated and cooled. No remotely operated valves, comparators or the like are needed.

  2. Strain and stability of ultrathin Ge layers in Si/Ge/Si axial heterojunction nanowires

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

    Ross, Frances M.; Stach, Eric A.; Wen, Cheng -Yen; Reuter, Mark C.; Su, Dong

    2015-03-11T23:59:59.000Z

    The abrupt heterointerfaces in the Si/Ge materials system presents useful possibilities for electronic device engineering because the band structure can be affected by strain induced by the lattice mismatch. In planar layers, heterointerfaces with abrupt composition changes are difficult to realize without introducing misfit dislocations. However, in catalytically grown nanowires, abrupt heterointerfaces can be fabricated by appropriate choice of the catalyst. Here we grow nanowires containing Si/Ge and Si/Ge/Si structures respectively with sub-1nm thick Ge "quantum wells" and we measure the interfacial strain fields using geometric phase analysis. Narrow Ge layers show radial strains of several percent, with a correspondingmore »dilation in the axial direction. Si/Ge interfaces show lattice rotation and curvature of the lattice planes. We conclude that high strains can be achieved, compared to what is possible in planar layers. In addition, we study the stability of these heterostructures under heating and electron beam irradiation. The strain and composition gradients are supposed to the cause of the instability for interdiffusion.« less

  3. Ultra-high speed permanent magnet axial gap alternator with multiple stators

    DOE Patents [OSTI]

    Hawsey, Robert A. (Oak Ridge, TN); Bailey, J. Milton (Knoxville, TN)

    1991-01-01T23:59:59.000Z

    An ultra-high speed, axial gap alternator that can provide an output to a plurality of loads, the alternator providing magnetic isolation such that operating conditions in one load will not affect operating conditions of another load. This improved alternator uses a rotor member disposed between a pair of stator members, with magnets disposed in each of the rotor member surfaces facing the stator members. The magnets in one surface of the rotor member, which alternate in polarity, are isolated from the magnets in the other surface of the rotor member by a disk of magnetic material disposed between the two sets of magents. In the preferred embodiment, this disk of magnetic material is laminated between two layers of non-magnetic material that support the magnets, and the magnetic material has a peripheral rim that extends to both surfaces of the rotor member to enhance the structural integrity. The stator members are substantially conventional in construction in that equally-spaced and radially-oriented slots are provided, and winding members are laid in these slots. A unit with multiple rotor members and stator members is also described.

  4. Octupole deformation in light actinides within an analytic quadrupole octupole axially symmetric model with Davidson potential

    E-Print Network [OSTI]

    Bonatsos, Dennis; Minkov, N; Karampagia, S; Petrellis, D

    2015-01-01T23:59:59.000Z

    The analytic quadrupole octupole axially symmetric model, which had successfully predicted 226Ra and 226Th as lying at the border between the regions of octupole deformation and octupole vibrations in the light actinides using an infinite well potential (AQOA-IW), is made applicable to a wider region of nuclei exhibiting octupole deformation, through the use of a Davidson potential (AQOA-D). Analytic expressions for energy spectra and B(E1), B(E2), B(E3) transition rates are derived. The spectra of 222-226Ra and 224,226Th are described in terms of the two parameters phi_0 (expressing the relative amount of octupole vs. quadrupole deformation) and beta_0 (the position of the minimum of the Davidson potential), while the recently determined B(EL) transition rates of 224Ra, presenting stable octupole deformation, are successfully reproduced. A procedure for gradually determining the parameters appearing in the B(EL) transitions from a minimum set of data, thus increasing the predictive power of the model, is out...

  5. Types of Commissioning

    Broader source: Energy.gov [DOE]

    Several commissioning types exist to address the specific needs of equipment and systems across both new and existing buildings. The following commissioning types provide a good overview.

  6. Turbulent flow in graphene

    E-Print Network [OSTI]

    Kumar S. Gupta; Siddhartha Sen

    2010-06-05T23:59:59.000Z

    We demonstrate the possibility of a turbulent flow of electrons in graphene in the hydrodynamic region, by calculating the corresponding turbulent probability density function. This is used to calculate the contribution of the turbulent flow to the conductivity within a quantum Boltzmann approach. The dependence of the conductivity on the system parameters arising from the turbulent flow is very different from that due to scattering.

  7. B -> K1 gamma and tests of factorization for two-body non leptonic Bdecays with axial-vector mesons

    E-Print Network [OSTI]

    G. Nardulli; T. N. Pham

    2005-07-30T23:59:59.000Z

    The large branching ratio for B-> K1 gamma recently measured at Belle implies a large B -> K1 transition form factor and large branching ratios for non leptonic B decays involving an axial-vector meson. In this paper we present an analysis of two-body B decays with an axial-vector meson in the final state using naive factorization and the B -> K1 form factors obtained from the measured radiative decays. We find that the predicted B -> J/psi K1 branching ratio is in agreement with experiment. We also suggest that the decay rates of B -> K1 pi, B -> a1 K and B -> b1 K could be used to test the factorization ansatz.

  8. Domain decomposition for coupled Stokes and Darcy flows q Danail Vassilev a

    E-Print Network [OSTI]

    Yotov, Ivan

    and fluid flow Stokes­Darcy flow Beavers­Joseph­Saffman condition Mixed finite element a b s t r a c t A non iteration. Finite element techniques appropriate for the type of each subdomain problem are used-overlapping domain decomposition method is presented to solve a coupled Stokes­ Darcy flow problem in parallel

  9. A Uniform Type Structure for Secure Information KOHEI HONDA

    E-Print Network [OSTI]

    Honda, Kohei

    A Uniform Type Structure for Secure Information Flow KOHEI HONDA Queen Mary, University of London . . . . . . . . . . . . . . . . . 13 Author's address: K. Honda, Department of Computer Science, Queen Mary, University of London, Mile. TBD, No. TDB, Month Year, Pages 1­83. #12;2 · Kohei Honda and Nobuko Yoshida 2.5 Linear/Affine Typing

  10. 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...

  11. Types of Costs Types of Cost Estimates

    E-Print Network [OSTI]

    Boisvert, Jeff

    05-1 · Types of Costs · Types of Cost Estimates · Methods to estimate capital costs MIN E 408-Revenue Relationships · Capital Costs (or first cost or capital investment): ­ Expenditures made to acquire or develop capital assets ­ Three main classes of capital costs: 1. Depreciable Investment: · Investment allocated

  12. Laser cooling in the Penning trap: an analytical model for cooling rates in the presence of an axializing field

    E-Print Network [OSTI]

    R. J. Hendricks; E. S. Phillips; D. M. Segal; R. C. Thompson

    2007-09-24T23:59:59.000Z

    Ions stored in Penning traps may have useful applications in the field of quantum information processing. There are, however, difficulties associated with the laser cooling of one of the radial motions of ions in these traps, namely the magnetron motion. The application of a small radio-frequency quadrupolar electric potential resonant with the sum of the two radial motional frequencies has been shown to couple these motions and to lead to more efficient laser cooling. We present an analytical model that enables us to determine laser cooling rates in the presence of such an 'axializing' field. It is found that this field leads to an averaging of the laser cooling rates for the two motions and hence improves the overall laser cooling efficiency. The model also predicts shifts in the motional frequencies due to the axializing field that are in qualitative agreement with those measured in recent experiments. It is possible to determine laser cooling rates experimentally by studying the phase response of the cooled ions to a near resonant excitation field. Using the model developed in this paper, we study the expected phase response when an axializing field is present.

  13. Axial and transverse acoustic radiation forces on a fluid sphere placed arbitrarily in Bessel beam standing wave tweezers

    SciTech Connect (OSTI)

    Mitri, F.G., E-mail: mitri@chevron.com

    2014-03-15T23:59:59.000Z

    The axial and transverse radiation forces on a fluid sphere placed arbitrarily in the acoustical field of Bessel beams of standing waves are evaluated. The three-dimensional components of the time-averaged force are expressed in terms of the beam-shape coefficients of the incident field and the scattering coefficients of the fluid sphere using a partial-wave expansion (PWE) method. Examples are chosen for which the standing wave field is composed of either a zero-order (non-vortex) Bessel beam, or a first-order Bessel vortex beam. It is shown here, that both transverse and axial forces can push or pull the fluid sphere to an equilibrium position depending on the chosen size parameter ka (where k is the wave-number and a the sphere’s radius). The corresponding results are of particular importance in biophysical applications for the design of lab-on-chip devices operating with Bessel beams standing wave tweezers. Moreover, potential investigations in acoustic levitation and related applications in particle rotation in a vortex beam may benefit from the results of this study. -- Highlights: •The axial and transverse forces on a fluid sphere in acoustical Bessel beams tweezers are evaluated. •The attraction or repulsion to an equilibrium position in the standing wave field is examined. •Potential applications are in particle manipulation using standing waves.

  14. Simultaneous fog formation and thermophoretic droplet deposition in a turbulent pipe flow

    SciTech Connect (OSTI)

    Epstein, M.; Hauser, G.M. (Fauske and Associates, Inc., Burr Ridge, IL (USA))

    1991-02-01T23:59:59.000Z

    Simultaneous aerosol formation by equilibrium condensation and the migration of the resulting droplets to the cold surface by thermophoresis is studied theoretically for a turbulent pipe flow. The problem is one in which a mixture of a vapor and noncondensable gas flows into a section of pipe where the pipe wall is cooled to below the dew point of the vapor. Because the temperature gradient at the pipe wall decays to zero once the gas travels far enough into the pipe, only some fraction of the droplets formed will deposit on the pipe wall. The equations of energy and diffusion suggest that turbulence leads to a discontinuity in the aerosol (fog) concentration at the boundary between the fog and clear regions. Numerical solutions are obtained for CsOH fog formation and deposition in steam flow, a particular case of current practical interest in water reactor safety. The axial and radial variations of the aerosol and vapor concentrations are displayed graphically, as are the location of the fog boundary as a function of axial distance and the efficiency of deposition as a function of the pipe wall temperature.

  15. Conductive and convective heat transfer in fluid flows between differentially heated and rotating cylinders

    E-Print Network [OSTI]

    Lopez, Jose M; Avila, Marc

    2015-01-01T23:59:59.000Z

    The flow of fluid confined between a heated rotating cylinder and a cooled stationary cylinder is a canonical experiment for the study of heat transfer in engineering. The theoretical treatment of this system is greatly simplified if the cylinders are assumed to be of infinite length or periodic in the axial direction, in which cases heat transfer occurs only through conduction as in a solid. We here investigate numerically heat transfer and the onset of turbulence in such flows by using both periodic and no-slip boundary conditions in the axial direction. We obtain a simple linear criterion that determines whether the infinite-cylinder assumption can be employed. The curvature of the cylinders enters this linear relationship through the slope and additive constant. For a given length-to-gap aspect ratio there is a critical Rayleigh number beyond which the laminar flow in the finite system is convective and so the behaviour is entirely different from the periodic case. The criterion does not depend on the Pra...

  16. Dynamics of multiple viscoelastic carbon nanotube based nanocomposites with axial magnetic field

    SciTech Connect (OSTI)

    Karli?i?, Danilo; Caji?, Milan [Mathematical Institute of the SASA, Kneza Mihaila 36, Belgrade 11001 (Serbia); Murmu, Tony [School of Engineering, University of the West of Scotland, Paisley PA12BE (United Kingdom); Kozi?, Predrag [Faculty of Mechanical Engineering, University of Niš, A. Medvedeva 14, 18000 Niš (Serbia); Adhikari, Sondipon [College of Engineering, Swansea University, Singleton Park, Swansea SA2 8PP (United Kingdom)

    2014-06-21T23:59:59.000Z

    Nanocomposites and magnetic field effects on nanostructures have received great attention in recent years. A large amount of research work was focused on developing the proper theoretical framework for describing many physical effects appearing in structures on nanoscale level. Great step in this direction was successful application of nonlocal continuum field theory of Eringen. In the present paper, the free transverse vibration analysis is carried out for the system composed of multiple single walled carbon nanotubes (MSWCNT) embedded in a polymer matrix and under the influence of an axial magnetic field. Equivalent nonlocal model of MSWCNT is adopted as viscoelastically coupled multi-nanobeam system (MNBS) under the influence of longitudinal magnetic field. Governing equations of motion are derived using the Newton second low and nonlocal Rayleigh beam theory, which take into account small-scale effects, the effect of nanobeam angular acceleration, internal damping and Maxwell relation. Explicit expressions for complex natural frequency are derived based on the method of separation of variables and trigonometric method for the “Clamped-Chain” system. In addition, an analytical method is proposed in order to obtain asymptotic damped natural frequency and the critical damping ratio, which are independent of boundary conditions and a number of nanobeams in MNBS. The validity of obtained results is confirmed by comparing the results obtained for complex frequencies via trigonometric method with the results obtained by using numerical methods. The influence of the longitudinal magnetic field on the free vibration response of viscoelastically coupled MNBS is discussed in detail. In addition, numerical results are presented to point out the effects of the nonlocal parameter, internal damping, and parameters of viscoelastic medium on complex natural frequencies of the system. The results demonstrate the efficiency of the suggested methodology to find the closed form solutions for the free vibration response of multiple nanostructure systems under the influence of magnetic field.

  17. Criticality and axial offset searches based on the integrated neutron balance approach

    SciTech Connect (OSTI)

    Dall'Osso, A. [AREVA NP Tour AREVA, 92084 Paris La Defense Cedex (France); Van Geemert, R. [AREVA GmbH, Paul Gossenstrasse 100, D-91058 Erlangen (Germany)

    2013-07-01T23:59:59.000Z

    Criticality and axial offset (AO) searches are key features in the simulation of plant operation procedures. Typically, the dedicated algorithms consist of either a Newton method or a secant method that features the successive computation of difference quotients to be used as derivatives. Within this context, computational robustness and efficiency are of paramount importance. This applies in particular to when the variations imposed during the search are spatially heterogeneous, such as in the case of tuning control rod positions for achieving target AO. In order to optimize this kind of search capability in AREVA NP's reactor code ARTEMIS in accordance with this design principle, a generalized approach has been implemented that harmonizes very well numerically with the overall multi-physics iterative solution process. As embedded in the latter, the new neutronic integral re-balancing approach is defined through periodic whole-core space-energy integrations of the principal terms in the core-integrated process-rate balance terms (i.e. neutron absorption, production and leakage). This procedure yields sequences of single zero-dimensional equations from which the chosen tuning parameters can be solved directly in dependence of the imposed (and systematically fixed) values for the response quantities k{sub eff} and/or AO. The converged result of the iteration sequence of successively obtained search parameter values is final in terms of being fully consistent with the entire set of multi-physics equations while enabling the accurate fulfillment of the target response value. The k etc and AO searches can be pursued simultaneously. Judging from the results of pursued verifications, the neutronic integral re-balancing approach fulfils the above-mentioned expectations convincingly. Specific verification examples are presented, such as the determination of the insertion depth of a critical control bank, a double search on target criticality and target AO by adjusting the boron concentration and the position of a control bank, and a critical power search during reactor cycle stretch out. (authors)

  18. Microelectromechanical flow control apparatus

    DOE Patents [OSTI]

    Okandan, Murat (NE Albuquerque, NM)

    2009-06-02T23:59:59.000Z

    A microelectromechanical (MEM) flow control apparatus is disclosed which includes a fluid channel formed on a substrate from a first layer of a nonconducting material (e.g. silicon nitride). A first electrode is provided on the first layer of the nonconducting material outside the flow channel; and a second electrode is located on a second layer of the nonconducting material above the first layer. A voltage applied between the first and second electrodes deforms the fluid channel to increase its cross-sectional size and thereby increase a flow of a fluid through the channel. In certain embodiments of the present invention, the fluid flow can be decreased or stopped by applying a voltage between the first electrode and the substrate. A peristaltic pumping of the fluid through the channel is also possible when the voltage is applied in turn between a plurality of first electrodes and the substrate. A MEM flow control assembly can also be formed by providing one or more MEM flow control devices on a common substrate together with a submicron filter. The MEM flow control assembly can optionally include a plurality of pressure sensors for monitoring fluid pressure and determining flow rates through the assembly.

  19. A flowing plasma model to describe drift waves in a cylindrical helicon discharge

    SciTech Connect (OSTI)

    Chang, L.; Hole, M. J.; Corr, C. S. [Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2011-04-15T23:59:59.000Z

    A two-fluid model developed originally to describe wave oscillations in the vacuum arc centrifuge, a cylindrical, rapidly rotating, low temperature, and confined plasma column, is applied to interpret plasma oscillations in a RF generated linear magnetized plasma [WOMBAT (waves on magnetized beams and turbulence)], with similar density and field strength. Compared to typical centrifuge plasmas, WOMBAT plasmas have slower normalized rotation frequency, lower temperature, and lower axial velocity. Despite these differences, the two-fluid model provides a consistent description of the WOMBAT plasma configuration and yields qualitative agreement between measured and predicted wave oscillation frequencies with axial field strength. In addition, the radial profile of the density perturbation predicted by this model is consistent with the data. Parameter scans show that the dispersion curve is sensitive to the axial field strength and the electron temperature, and the dependence of oscillation frequency with electron temperature matches the experiment. These results consolidate earlier claims that the density and floating potential oscillations are a resistive drift mode, driven by the density gradient. To our knowledge, this is the first detailed physics model of flowing plasmas in the diffusion region away from the RF source. Possible extensions to the model, including temperature nonuniformity and magnetic field oscillations, are also discussed.

  20. Hybrid experimental-numerical determination of the loading path to fracture in TRIP780 sheets subjected to multi-axial loading

    E-Print Network [OSTI]

    Dunand, Matthieu

    2010-01-01T23:59:59.000Z

    The development of ductile fracture models of metals requires reliable measurements of the stress and strain histories up to the onset of fracture in multi-axial experiments. In the present work, a hybrid experimental-numerical ...

  1. Numerical and experimental study on the effects of elbows upon the flow downstream

    E-Print Network [OSTI]

    Tung, Karine

    1998-01-01T23:59:59.000Z

    /m' p ?, = 13579. 04 Kg/m CHAPTER I INTRODUCTION The presence of one or two elbows in a piping system is known to have an effect on the axial velocity profile and the amount of swirl present downstream of the elbows. As most flowmeters... (using a three-hole Pitot probe) where natural gas with a density of 20. 7 kg/m' and viscosity of 1. 1E ' kg/m s was flowing at a bulk average velocity of 19. 9 m/s through the 20. 3 cm diameter piping systems described above. The effect of these pipe...

  2. OPTIMIZATION OF COAL PARTICLE FLOW PATTERNS IN LOW NOX BURNERS

    SciTech Connect (OSTI)

    Jost O.L. Wendt; Gregory E. Ogden; Jennifer Sinclair; Stephanus Budilarto

    2001-09-04T23:59:59.000Z

    It is well understood that the stability of axial diffusion flames is dependent on the mixing behavior of the fuel and combustion air streams. Combustion aerodynamic texts typically describe flame stability and transitions from laminar diffusion flames to fully developed turbulent flames as a function of increasing jet velocity. Turbulent diffusion flame stability is greatly influenced by recirculation eddies that transport hot combustion gases back to the burner nozzle. This recirculation enhances mixing and heats the incoming gas streams. Models describing these recirculation eddies utilize conservation of momentum and mass assumptions. Increasing the mass flow rate of either fuel or combustion air increases both the jet velocity and momentum for a fixed burner configuration. Thus, differentiating between gas velocity and momentum is important when evaluating flame stability under various operating conditions. The research efforts described herein are part of an ongoing project directed at evaluating the effect of flame aerodynamics on NO{sub x} emissions from coal fired burners in a systematic manner. This research includes both experimental and modeling efforts being performed at the University of Arizona in collaboration with Purdue University. The objective of this effort is to develop rational design tools for optimizing low NO{sub x} burners. Experimental studies include both cold-and hot-flow evaluations of the following parameters: primary and secondary inlet air velocity, coal concentration in the primary air, coal particle size distribution and flame holder geometry. Hot-flow experiments will also evaluate the effect of wall temperature on burner performance.

  3. A Compact Disk Type Plasma Propulsion System with Modulated Magnetic Field for Nanoscale Space Vehicles

    SciTech Connect (OSTI)

    Fukuda, Takeshi; Ueda, Satoshi; Ohnishi, Yukihiro; Inomoto, Michiaki [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, 565-0871 Osaka (Japan)

    2008-12-31T23:59:59.000Z

    A compact 5 mm disk type plasma thruster simply composed of only a set of antenna windings and bias field coil which produces significant thrust of 0.74 mN with rotating magnetic field has been proposed and successfully developed for future applications to low altitude nanosatellites. The key technology issue is that the rotating speed is set above the ion plasma frequency but far below the electron plasma frequency, in order to produce the electron drag current and axial electric field as a consequence of the interaction with the bias field. The formation of axial electric field was confirmed and the produced plasma density was >6x10{sup 18} m{sup -3}, whereas the power consumption is 500 W in the inductively coupled mode of operation. The anticipated thrust density and specific thrust could potentially be extended to 7.64 Nm{sup -2} and 850 s, respectively, which is comparable to conventional Hall effect thrusters.

  4. Hydrodynamic forces on smooth inclined cylinder in oscillatory flow

    SciTech Connect (OSTI)

    Kang, H.G. [Dalian Univ. of Technology (China)

    1993-12-31T23:59:59.000Z

    The hydrodynamic forces on a smooth inclined circular cylinder exposed to oscillating flow were experimentally investigated at Reynolds number (Re) in the range 40,000--200,000 and Keulegan-Capenter number (Kc) in the interval from 5--40. In the test, Re number and Kc number were varied systematically. The inertia force coefficient (C{sub M}) and the drag force coefficient (C{sub D}) in Morison equation were determined form the measured loads and the water particle kinematics. This analysis uses a modified form of Morison equation since it uses the normal velocity and acceleration. Thus, the applicability of the Cross Flow Principle was assumed. This principle, simply stated, is as follows: the force acting in the direction normal to the axis of a cylinder placed at some oblique angle to the direction of flow is expressed in terms of the normal component of flow only, and the axial component is disregarded. Both total in-line force coefficient (C{sub F}) and transverse force (lift) coefficient (C{sub L}) were analyzed in terms of their maximum and root mean square values. All the in-line and lift force coefficient were given as a functions of Re and Kc number. From this research, it can be seen that the Cross-Flow Principle does not always work well. It seems valid for the total in-line force at high Re and large Kc number; the C{sub M} for {alpha} = 45{degree} is larger and the C{sub D} for {alpha} = 45{degree} is smaller than that for {alpha} = 90{degree} and Re {ge} 80,000. The hydrodynamic force coefficients C{sub D} and C{sub M} for the inclined cylinder are only the functions of oblique angle ({alpha}) and Kc number, but not of the Re number.

  5. Controls of Wellbore Flow Regimes on Pump Effluent Composition

    SciTech Connect (OSTI)

    James Martin-Hayden; plummer; Sanford Britt

    2014-01-01T23:59:59.000Z

    Where well water and formation water are compositionally different or heterogeneous, pump effluent composition will vary due to partial mixing and transport induced by pumping. Investigating influences of purging and sampling methodology on composition variability requires quantification of wellbore flow regimes and mixing. As a basis for this quantification, analytical models simulating Poiseuille flow were developed to calculate flow paths and travel times. Finite element modeling was used to incorporate influences of mixing. Parabolic velocity distributions within the screened interval accelerate with cumulative inflow approaching the pump intake while an annulus of inflowing formation water contracts uniformly to displace an axial cylinder of pre-pumping well water as pumping proceeds. Increased dispersive mixing forms a more diffuse formation water annulus and the contribution of formation water to pump effluent increases more rapidly. Models incorporating viscous flow and diffusion scale mixing show that initially pump effluent is predominantly pre-pumping well water and compositions vary most rapidly. After two screen volumes of pumping, 94% of pump effluent is inflowing formation water. Where the composition of formation water and pre-pumping well water are likely to be similar, pump effluent compositions will not vary significantly and may be collected during early purging or with passive sampling. However, where these compositions are expected to be considerably different or heterogeneous, compositions would be most variable during early pumping, that is, when samples are collected during low-flow sampling. Purging of two screen volumes would be required to stabilize the content and collect a sample consisting of 94% formation water.

  6. Magnetically stimulated fluid flow patterns

    ScienceCinema (OSTI)

    Martin, Jim; Solis, Kyle

    2014-08-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  7. Magnetically stimulated fluid flow patterns

    SciTech Connect (OSTI)

    Martin, Jim; Solis, Kyle

    2014-03-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  8. Types of Reuse

    Broader source: Energy.gov [DOE]

    The following provides greater detail regarding the types of reuse pursued for LM sites. It should be noted that many actual reuses combine several types of the uses listed below.

  9. Flow cytometer jet monitor system

    DOE Patents [OSTI]

    Van den Engh, Ger (Seattle, WA)

    1997-01-01T23:59:59.000Z

    A direct jet monitor illuminates the jet of a flow cytometer in a monitor wavelength band which is substantially separate from the substance wavelength band. When a laser is used to cause fluorescence of the substance, it may be appropriate to use an infrared source to illuminate the jet and thus optically monitor the conditions within the jet through a CCD camera or the like. This optical monitoring may be provided to some type of controller or feedback system which automatically changes either the horizontal location of the jet, the point at which droplet separation occurs, or some other condition within the jet in order to maintain optimum conditions. The direct jet monitor may be operated simultaneously with the substance property sensing and analysis system so that continuous monitoring may be achieved without interfering with the substance data gathering and may be configured so as to allow the front of the analysis or free fall area to be unobstructed during processing.

  10. PWR FLECHT SEASET 21-rod bundle flow blockage task data and analysis report. NRC/EPRI/Westinghouse Report No. 11. Appendices K-P

    SciTech Connect (OSTI)

    Loftus, M.J.; Hochreiter, L.E.; Lee, N.; McGuire, M.F.; Wenzel, A.H.; Valkovic, M.M.

    1982-09-01T23:59:59.000Z

    This report presents data and limited analysis from the 21-Rod Bundle Flow Blockage Task of the Full-Length Emergency Cooling Heat Transfer Separate Effects and Systems Effects Test Program (FLECHT SEASET). The tests consisted of forced and gravity reflooding tests utilizing electrical heater rods with a cosine axial power profile to simulate PWR nuclear core fuel rod arrays. Steam cooling and hydraulic characteristics tests were also conducted. These tests were utilized to determine effects of various flow blockage configurations (shapes and distributions) on reflooding behavior, to aid in development/assessment of computational models in predicting reflooding behavior of flow blockage configurations, and to screen flow blockage configurations for future 163-rod flow blockage bundle tests.

  11. Parallel flow diffusion battery

    DOE Patents [OSTI]

    Yeh, H.C.; Cheng, Y.S.

    1984-01-01T23:59:59.000Z

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  12. Optical flow switching

    E-Print Network [OSTI]

    Chan, Vincent W. S.

    Present-day networks are being challenged by dramatic increases in bandwidth demand of emerging applications. We will explore a new transport, ldquooptical flow switchingrdquo, that will enable significant growth and ...

  13. Olefin Autoxidation in Flow

    E-Print Network [OSTI]

    Neuenschwander, Ulrich

    Handling hazardous multiphase reactions in flow brings not only safety advantages but also significantly improved performance, due to better mass transfer characteristics. In this paper, we present a continuous microreactor ...

  14. Conjugate flow action functionals

    SciTech Connect (OSTI)

    Venturi, Daniele, E-mail: daniele-venturi@brown.edu [Division of Applied Mathematics, Brown University, Rhode Island 02912 (United States)] [Division of Applied Mathematics, Brown University, Rhode Island 02912 (United States)

    2013-11-15T23:59:59.000Z

    We present a new general framework to construct an action functional for a non-potential field theory. The key idea relies on representing the governing equations relative to a diffeomorphic flow of curvilinear coordinates which is assumed to be functionally dependent on the solution field. Such flow, which will be called the conjugate flow, evolves in space and time similarly to a physical fluid flow of classical mechanics and it can be selected in order to symmetrize the Gâteaux derivative of the field equations with respect to suitable local bilinear forms. This is equivalent to requiring that the governing equations of the field theory can be derived from a principle of stationary action on a Lie group manifold. By using a general operator framework, we obtain the determining equations of such manifold and the corresponding conjugate flow action functional. In particular, we study scalar and vector field theories governed by second-order nonlinear partial differential equations. The identification of transformation groups leaving the conjugate flow action functional invariant could lead to the discovery of new conservation laws in fluid dynamics and other disciplines.

  15. Section 13: Flow control 1 Section 13: Flow control

    E-Print Network [OSTI]

    Kohlenbach, Ulrich

    Geometries for Energyefficient Flow Around Bodies Abstract 14:30 ­ 14:50: Elfriede Friedmann (Universität

  16. Electrochemical cell apparatus having axially distributed entry of a fuel-spent fuel mixture transverse to the cell lengths

    DOE Patents [OSTI]

    Reichner, P.; Dollard, W.J.

    1991-01-08T23:59:59.000Z

    An electrochemical apparatus is made having a generator section containing axially elongated electrochemical cells, a fresh gaseous feed fuel inlet, a gaseous feed oxidant inlet, and at least one gaseous spent fuel exit channel, where the spent fuel exit channel passes from the generator chamber to combine with the fresh feed fuel inlet at a mixing apparatus, reformable fuel mixture channel passes through the length of the generator chamber and connects with the mixing apparatus, that channel containing entry ports within the generator chamber, where the axis of the ports is transverse to the fuel electrode surfaces, where a catalytic reforming material is distributed near the reformable fuel mixture entry ports. 2 figures.

  17. Strong Room-temperature Negative Transconductance In An Axial Si/Ge Hetero-nanowire Tunneling Field-effect Transistor

    SciTech Connect (OSTI)

    Zhang, Peng; Le, Son T.; Hou, Xiaoxiao; Zaslavsky, A.; Perea, Daniel E.; Dayeh, Shadi A.; Picraux, Samuel T.

    2014-08-11T23:59:59.000Z

    We report on room-temperature negative transconductance (NTC) in axial Si/Ge hetero-nanowire tunneling field-effect transistors (TFETs). The NTC produces a current peak-to-valley ratio > 45, a high value for a Si-based device. We characterize the NTC characteristics over a range of gate VG and drain VD voltages, finding that NTC persists down to VD = –50 mV. The physical mechanism responsible for the NTC is the VG-induced depletion in the p-Ge section that eventually reduces the maximum electric field that triggers the tunneling ID, as confirmed via three-dimensional TCAD simulations.

  18. Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I.Skillicorn 1 Azimuthal asymmetry

    E-Print Network [OSTI]

    Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I.Skillicorn 1 Azimuthal asymmetry using energy flow method Azimuthal angle distribution at Q2 >100 GeV2 Energy flow method.Ukleja on behalf of the ZEUS Collaboration #12; Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I

  19. 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.

  20. Particle-in-Cell Modeling of Magnetized Argon Plasma Flow Through Small Mechanical Apertures

    SciTech Connect (OSTI)

    Adam B. Sefkow and Samuel A. Cohen

    2009-04-09T23:59:59.000Z

    Motivated by observations of supersonic argon-ion flow generated by linear helicon-heated plasma devices, a three-dimensional particle-in-cell (PIC) code is used to study whether stationary electrostatic layers form near mechanical apertures intersecting the flow of magnetized plasma. By self-consistently evaluating the temporal evolution of the plasma in the vicinity of the aperture, the PIC simulations characterize the roles of the imposed aperture and applied magnetic field on ion acceleration. The PIC model includes ionization of a background neutral-argon population by thermal and superthermal electrons, the latter found upstream of the aperture. Near the aperture, a transition from a collisional to a collisionless regime occurs. Perturbations of density and potential, with mm wavelengths and consistent with ion acoustic waves, propagate axially. An ion acceleration region of length ~ 200?300 ?D,e forms at the location of the aperture and is found to be an electrostatic double layer, with axially-separated regions of net positive and negative charge. Reducing the aperture diameter or increasing its length increases the double layer strength.

  1. Experimental Investigation of the Root Cause Mechanism and Effectiveness of Mitigating Actions for Axial Offset Anomaly in Pressurized Water Reactors

    SciTech Connect (OSTI)

    Said Abdel-Khalik

    2005-07-02T23:59:59.000Z

    Axial offset anomaly (AOA) in pressurized water reactors refers to the presence of a significantly larger measured negative axial offset deviation than predicted by core design calculations. The neutron flux depression in the upper half of high-power rods experiencing significant subcooled boiling is believed to be caused by the concentration of boron species within the crud layer formed on the cladding surface. Recent investigations of the root-cause mechanism for AOA [1,2] suggest that boron build-up on the fuel is caused by precipitation of lithium metaborate (LiBO2) within the crud in regions of subcooled boiling. Indirect evidence in support of this hypothesis was inferred from operating experience at Callaway, where lithium return and hide-out were, respectively, observed following power reductions and power increases when AOA was present. However, direct evidence of lithium metaborate precipitation within the crud has, heretofore, not been shown because of its retrograde solubility. To this end, this investigation has been undertaken in order to directly verify or refute the proposed root-cause mechanism of AOA, and examine the effectiveness of possible mitigating actions to limit its impact in high power PWR cores.

  2. Magnetic field distribution in the plasma flow generated by a plasma focus discharge

    SciTech Connect (OSTI)

    Mitrofanov, K. N., E-mail: mitrofan@triniti.ru [Troitsk Institute for Innovaiton and Fusion Research (Russian Federation); Krauz, V. I., E-mail: krauz_vi@nrcki.ru; Myalton, V. V.; Velikhov, E. P.; Vinogradov, V. P.; Vinogradova, Yu. V. [National Research Centre Kurchatov Institute (Russian Federation)

    2014-11-15T23:59:59.000Z

    The magnetic field in the plasma jet propagating from the plasma pinch region along the axis of the chamber in a megajoule PF-3 plasma focus facility is studied. The dynamics of plasma with a trapped magnetic flow is analyzed. The spatial sizes of the plasma jet region in which the magnetic field concentrates are determined in the radial and axial directions. The magnetic field configuration in the plasma jet is investigated: the radial distribution of the azimuthal component of the magnetic field inside the jet is determined. It is shown that the magnetic induction vector at a given point in space can change its direction during the plasma flight. Conclusions regarding the symmetry of the plasma flow propagation relative to the chamber axis are drawn.

  3. Removal of volatile organic compounds from polluted air in a reverse flow reactor: An experimental study

    SciTech Connect (OSTI)

    Beld, B. van de; Borman, R.A.; Derkx, O.R.; Woezik, B.A.A. van; Westerterp, K.R. (Univ. of Twente, Enschede (Netherlands). Dept. of Chemical Engineering)

    1994-12-01T23:59:59.000Z

    An experimental study of the reverse flow reactor for the purification of contaminated air has been carried out. An experimental reactor with an inner diameter of 0.145 m has been constructed. It almost completely reached the goal of an adiabatically operating system. The influence of several operating parameters such as gas velocity, cycle period, chemical character, and concentration of the pollutants and reactor pressure are discussed. The reactor could be operated autothermally provided that the inlet concentrations were sufficiently high. If a mixture of contaminants is fed to the reactor, it might be necessary to increase the total hydrocarbon concentration to assure an autothermal process. Increasing the reactor pressure will hardly change the axial temperature profiles, if the mass flux is kept constant. Increasing the mass flow rate will lead to a higher plateau temperature. Not only the reactor behavior at fixed operating conditions, but also the response of the reactor toward variations in inlet conditions is reported.

  4. Gaseous Flows in Galaxies

    E-Print Network [OSTI]

    F. Combes

    2007-09-02T23:59:59.000Z

    The gas component plays a major role in the dynamics of spiral galaxies, because of its dissipative character, and its ability to exchange angular momentum with stars in the disk. Due to its small velocity dispersion, it triggers gravitational instabilities, and the corresponding non-axisymmetric patterns produce gravity torques, which mediate these angular momentum exchanges. When a srong bar pattern develops with the same pattern speed all over the disk, only gas inside corotation can flow towards the center. But strong bars are not long lived in presence of gas, and multiple-speed spiral patterns can develop between bar phases, and help the galaxy to accrete external gas flowing from cosmic filaments. The gas is then intermittently driven to the galaxy center, to form nuclear starbursts and fuel an active nucleus. The various time-scales of these gaseous flows are described.

  5. Multiphase cooling flows

    E-Print Network [OSTI]

    Peter A. Thomas

    1996-08-20T23:59:59.000Z

    I discuss the multiphase nature of the intracluster medium whose neglect can lead to overestimates of the baryon fraction of clusters by up to a factor of two. The multiphase form of the cooling flow equations are derived and reduced to a simple form for a wide class of self-similar density distributions. It is shown that steady-state cooling flows are \\emph{not} consistent with all possible emissivity profiles which can therefore be used as a test of the theory. In combination, they provide strong constraints on the mass distribution within the cooling radius.

  6. Turbulent flow and drag over fixed two-and three-dimensional dunes Jeremy G. Venditti1,2

    E-Print Network [OSTI]

    Venditti, Jeremy G.

    measurements of turbulent flow were obtained over a fixed flat bed, two- dimensional (2-D) dunes and four types over 2-D dunes conforms with previous observations of flow over mobile and fixed bed forms. Bed formTurbulent flow and drag over fixed two- and three-dimensional dunes Jeremy G. Venditti1,2 Received

  7. Observation Predicates in Flow Logic Flemming Nielson, Hanne Riis Nielson and Hongyan Sun

    E-Print Network [OSTI]

    and soft type systems we explore flow analyses with hard constraints on the admissi- ble solutions. We show cannot go wrong", and hence only strong typing can be seen as a program development methodology. Soft and similar formalisms such as Datalog. 1 Introduction In the world of type systems one frequently

  8. Simulations Data Simulation Type

    E-Print Network [OSTI]

    Wang, Xiaorui "Ray"

    to request different simulations data. The flow chart above demonstrates the different steps and options@ornl.gov) Autotune Drupal 7 CMS Current building energy models (BEMs), using EnergyPlus or other simulations, are unreliable because they have to constantly be calibrated to match actual energy usage data. Currently

  9. Typed Self-Optimization

    E-Print Network [OSTI]

    Brown, Matt

    2013-01-01T23:59:59.000Z

    type T y[O]. The operator IsIs is self-applicative, in thatargument t is any of Is[O] or IsIs, and otherwise behavesproof constant introduced by IsIs proves that the type of t

  10. Loss mechanisms in turbine tip clearance flows

    E-Print Network [OSTI]

    Huang, Arthur (Arthur C.)

    2011-01-01T23:59:59.000Z

    Numerical simulations of tip clearance ow have been carried out to dene the loss generation mechanisms associated with tip leakage in unshrouded axial turbines. Mix- ing loss between the leakage, which takes the form of a ...

  11. Molecular dynamics simulations of oscillatory Couette flows with slip boundary conditions

    E-Print Network [OSTI]

    Priezjev, Nikolai V

    2012-01-01T23:59:59.000Z

    The effect of interfacial slip on steady-state and time-periodic flows of monatomic liquids is investigated using non-equilibrium molecular dynamics simulations. The fluid phase is confined between atomically smooth rigid walls, and the fluid flows are induced by moving one of the walls. In steady shear flows, the slip length increases almost linearly with shear rate. We found that the velocity profiles in oscillatory flows are well described by the Stokes flow solution with the slip length that depends on the local shear rate. Interestingly, the rate dependence of the slip length obtained in steady shear flows is recovered when the slip length in oscillatory flows is plotted as a function of the local shear rate magnitude. For both types of flows, the friction coefficient at the liquid-solid interface correlates well with the structure of the first fluid layer near the solid wall.

  12. Molecular dynamics simulations of oscillatory Couette flows with slip boundary conditions

    E-Print Network [OSTI]

    Nikolai V. Priezjev

    2012-08-27T23:59:59.000Z

    The effect of interfacial slip on steady-state and time-periodic flows of monatomic liquids is investigated using non-equilibrium molecular dynamics simulations. The fluid phase is confined between atomically smooth rigid walls, and the fluid flows are induced by moving one of the walls. In steady shear flows, the slip length increases almost linearly with shear rate. We found that the velocity profiles in oscillatory flows are well described by the Stokes flow solution with the slip length that depends on the local shear rate. Interestingly, the rate dependence of the slip length obtained in steady shear flows is recovered when the slip length in oscillatory flows is plotted as a function of the local shear rate magnitude. For both types of flows, the friction coefficient at the liquid-solid interface correlates well with the structure of the first fluid layer near the solid wall.

  13. Theoretical and experimental studies of churn flow in vertical tubes. Final technical report

    SciTech Connect (OSTI)

    Not Available

    1986-01-27T23:59:59.000Z

    The pattern known as churn flow is a highly unsteady pattern with stochastic features and is extremely complex. However, calculations show that for many geothermal wells the condition of churn flow consists over much of the length of the two phase zone. Furthermore, it frequently exists at the surface so that design of separation equipment and surface piping depends on the accurate modelling of this type of flow. It has been the long term purpose of this project to develop physically based models for churn flow which can be used as a basis for predicting holdup, frictional loss and heat transfer rates for this flow pattern in geothermal systems. To achieve this end, it was necessary to develop new methods for measuring the time dependent characteristics of the flow and thus be able to uncover the basic physics of the flow. Models can then be developed based on this understanding which characterizes the flow and equations for holdup, friction and heat transfer evolved.

  14. Your Guide to Diabetes: Type 1 and Type 2

    E-Print Network [OSTI]

    Rau, Don C.

    Your Guide to Diabetes: Type 1 and Type 2 National Diabetes Information Clearinghouse #12;#12;Your Guide to Diabetes: Type 1 and Type 2 #12;#12;Contents Learn about Diabetes ............................................................ 1 What is diabetes? .............................................................. 2 What

  15. Flow cytometry apparatus

    DOE Patents [OSTI]

    Pinkel, Daniel (Walnut Creek, CA)

    1991-01-01T23:59:59.000Z

    An obstruction across the flow chamber creates a one dimensional convergence of a sheath fluid. A passageway in the construction directs flat cells near to the area of one dimensional convergence in the sheath fluid to provide proper orientation of flat cells at fast rates.

  16. AGN and Cooling Flows

    E-Print Network [OSTI]

    James Binney

    2001-03-23T23:59:59.000Z

    For two decades the steady-state cooling-flow model has dominated the literature of cluster and elliptical-galaxy X-ray sources. For ten years this model has been in severe difficulty from a theoretical point of view, and it is now coming under increasing pressure observationally. For two decades the steady-state cooling-flow model has dominated the literature of cluster and elliptical-galaxy X-ray sources. For ten years this model has been in severe difficulty from a theoretical point of view, and it is now coming under increasing pressure observationally. A small number of enthusiasts have argued for a radically different interpretation of the data, but had little impact on prevailing opinion because the unsteady heating picture that they advocate is extremely hard to work out in detail. Here I explain why it is difficult to extract robust observational predictions from the heating picture. Major problems include the variability of the sources, the different ways in which a bi-polar flow can impact on X-ray emission, the weakness of synchrotron emission from sub-relativistic flows, and the sensitivity of synchrotron emission to a magnetic field that is probably highly localized.

  17. Experimental and Analytic Study on the Core Bypass Flow in a Very High Temperature Reactor

    SciTech Connect (OSTI)

    Richard Schultz

    2012-04-01T23:59:59.000Z

    Core bypass flow has been one of key issues in the very high temperature reactor (VHTR) design for securing core thermal margins and achieving target temperatures at the core exit. The bypass flow in a prismatic VHTR core occurs through the control element holes and the radial and axial gaps between the graphite blocks for manufacturing and refueling tolerances. These gaps vary with the core life cycles because of the irradiation swelling/shrinkage characteristic of the graphite blocks such as fuel and reflector blocks, which are main components of a core's structure. Thus, the core bypass flow occurs in a complicated multidimensional way. The accurate prediction of this bypass flow and counter-measures to minimize it are thus of major importance in assuring core thermal margins and securing higher core efficiency. Even with this importance, there has not been much effort in quantifying and accurately modeling the effect of the core bypass flow. The main objectives of this project were to generate experimental data for validating the software to be used to calculate the bypass flow in a prismatic VHTR core, validate thermofluid analysis tools and their model improvements, and identify and assess measures for reducing the bypass flow. To achieve these objectives, tasks were defined to (1) design and construct experiments to generate validation data for software analysis tools, (2) determine the experimental conditions and define the measurement requirements and techniques, (3) generate and analyze the experimental data, (4) validate and improve the thermofluid analysis tools, and (5) identify measures to control the bypass flow and assess its performance in the experiment.

  18. Vanishing Viscosity Method for Transonic Flow

    E-Print Network [OSTI]

    Gui-Qiang Chen; Marshall Slemrod; Dehua Wang

    2006-10-07T23:59:59.000Z

    A vanishing viscosity method is formulated for two-dimensional transonic steady irrotational compressible fluid flows with adiabatic constant $\\gamma\\in [1,3)$. This formulation allows a family of invariant regions in the phase plane for the corresponding viscous problem, which implies an upper bound uniformly away from cavitation for the viscous approximate velocity fields. Mathematical entropy pairs are constructed through the Loewner-Morawetz relation by entropy generators governed by a generalized Tricomi equation of mixed elliptic-hyperbolic type, and the corresponding entropy dissipation measures are analyzed so that the viscous approximate solutions satisfy the compensated compactness framework. Then the method of compensated compactness is applied to show that a sequence of solutions to the artificial viscous problem, staying uniformly away from stagnation, converges to an entropy solution of the inviscid transonic flow problem.

  19. Coupling free flow / porous-medium flow General idea

    E-Print Network [OSTI]

    Cirpka, Olaf Arie

    equation t (v) + div (vv ) - div(v) + p - g - qv = 0 Darcy flow equation t (S) - div K (p - g) - qpmT transport equation t (X) + div (vX - DsteamX) = qsteam 16/14 #12;Backup additional Darcy flow equations-Stokes 1 phase, 2 components, temperature sharp interface porous-medium / Darcy flow 2 phases, 2 component

  20. Fejer-type inequalities

    E-Print Network [OSTI]

    Mitroi, F C

    2011-01-01T23:59:59.000Z

    The aim of this paper is to present some new Fejer-type results for convex functions. Improvements of Young's inequality (the arithmetic-geometric mean inequality) and other applications to special means are pointed as well.

  1. Document Type: Subject Terms

    E-Print Network [OSTI]

    Major, Arkady

    Title: Authors: Source: Document Type: Subject Terms: Abstract: Full Text Word Count: ISSN at creating team results. In fact, it's priceless. Managers in Western corporations have received a lifetime

  2. Exact analysis of particle dynamics in combined field of finite duration laser pulse and static axial magnetic field

    SciTech Connect (OSTI)

    Sagar, Vikram; Sengupta, Sudip; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2012-11-15T23:59:59.000Z

    Dynamics of a charged particle is studied in the field of a relativistically intense linearly polarized finite duration laser pulse in the presence of a static axial magnetic field. For a finite duration laser pulse whose temporal shape is defined by Gaussian profile, exact analytical expressions are derived for the particle trajectory, momentum, and energy as function of laser phase. From the solutions, it is shown that, unlike for the monochromatic plane wave case, resonant phase locking time between the particle and laser pulse is finite. The net energy transferred to the particle does not increase monotonically but tends to saturate. It is further shown that appropriate tuning of cyclotron frequency of the particle with the characteristic frequency in the pulse spectrum can lead to the generation of accelerated particles with variable energies in MeV-TeV range.

  3. Two-dimensional simulations of thermonuclear burn in ignition-scale inertial confinement fusion targets under compressed axial magnetic fields

    SciTech Connect (OSTI)

    Perkins, L. J.; Logan, B. G.; Zimmerman, G. B.; Werner, C. J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2013-07-15T23:59:59.000Z

    We report for the first time on full 2-D radiation-hydrodynamic implosion simulations that explore the impact of highly compressed imposed magnetic fields on the ignition and burn of perturbed spherical implosions of ignition-scale cryogenic capsules. Using perturbations that highly convolute the cold fuel boundary of the hotspot and prevent ignition without applied fields, we impose initial axial seed fields of 20–100 T (potentially attainable using present experimental methods) that compress to greater than 4 × 10{sup 4} T (400 MG) under implosion, thereby relaxing hotspot areal densities and pressures required for ignition and propagating burn by ?50%. The compressed field is high enough to suppress transverse electron heat conduction, and to allow alphas to couple energy into the hotspot even when highly deformed by large low-mode amplitudes. This might permit the recovery of ignition, or at least significant alpha particle heating, in submarginal capsules that would otherwise fail because of adverse hydrodynamic instabilities.

  4. Electrochemical cell apparatus having axially distributed entry of a fuel-spent fuel mixture transverse to the cell lengths

    DOE Patents [OSTI]

    Reichner, Philip (Plum Borough, PA); Dollard, Walter J. (Churchill Borough, PA)

    1991-01-01T23:59:59.000Z

    An electrochemical apparatus (10) is made having a generator section (22) containing axially elongated electrochemical cells (16), a fresh gaseous feed fuel inlet (28), a gaseous feed oxidant inlet (30), and at least one gaseous spent fuel exit channel (46), where the spent fuel exit channel (46) passes from the generator chamber (22) to combine with the fresh feed fuel inlet (28) at a mixing apparatus (50), reformable fuel mixture channel (52) passes through the length of the generator chamber (22) and connects with the mixing apparatus (50), that channel containing entry ports (54) within the generator chamber (22), where the axis of the ports is transverse to the fuel electrode surfaces (18), where a catalytic reforming material is distributed near the reformable fuel mixture entry ports (54).

  5. Message Flow Modulator Final Report

    E-Print Network [OSTI]

    Boyer, Robert Stephen

    operational environment at the Patuxent River Naval Air Test Center with scenarios developed by an independent in testing and demonstrating the flow modulator at the Patuxent River Naval Air Test Center. #12;MESSAGE FLOW

  6. Radial flow pulse jet mixer

    DOE Patents [OSTI]

    VanOsdol, John G.

    2013-06-25T23:59:59.000Z

    The disclosure provides a pulse jet mixing vessel for mixing a plurality of solid particles. The pulse jet mixing vessel is comprised of a sludge basin, a flow surface surrounding the sludge basin, and a downcoming flow annulus between the flow surface and an inner shroud. The pulse jet mixing vessel is additionally comprised of an upper vessel pressurization volume in fluid communication with the downcoming flow annulus, and an inner shroud surge volume separated from the downcoming flow annulus by the inner shroud. When the solid particles are resting on the sludge basin and a fluid such as water is atop the particles and extending into the downcoming flow annulus and the inner shroud surge volume, mixing occurs by pressurization of the upper vessel pressurization volume, generating an inward radial flow over the flow surface and an upwash jet at the center of the sludge basin.

  7. Flow (2008) Director: Irena Salina

    E-Print Network [OSTI]

    Hemmers, Oliver

    2008-01-01T23:59:59.000Z

    Flow (2008) Director: Irena Salina Run Time: 93 min. Summary: ,Irena Salina's documentary film://documentaryfilms.suite101.com/article.cfm/desperate_for_water_irena_salinas_movie_flow No Dumb Questions (2001) Director

  8. 1206 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 4, AUGUST 2008 Dual-Species Plasmas Illustrate MHD Flows

    E-Print Network [OSTI]

    Bellan, Paul M.

    to pinch down at the axial midpoint, decreasing the axial variation. The axial magnetic field are with the California Institute of Technology, Pasadena, CA 91125 USA (e-mail: eve@caltech.edu). Digital Object

  9. Flow regime mapping of vertical two-phase downflow in a ribbed annulus

    SciTech Connect (OSTI)

    Kielpinski, A.L.

    1992-12-01T23:59:59.000Z

    Two-phase flow regimes have been mapped for vertical, cocurrent downflow in a narrow annulus which is partially segmented by the presence of longitudinal ribs. This geometry and flow condition has application to the analysis of a Large-Break Loss of Coolant Accident (LB-LOCA) in the production K-Reactor at the Savannah River Site (SRS). The ribbed annular geometry, particularly the presence of non-sealing ribs, gives rise to some unique phenomenological features. The flow behavior is influenced by the partial segmentation of the annulus into four quadrants or subchannels. A random element is induced by the natural bowing of the slender tubes; the width of the azimuthal flow path between two subchannels at a given axial location is indeterminate, and can take on any value between zero and the maximum clearance of 7.6 {times} l0{sup {minus}4} m. When the rib gap is zero at a given location, it is at a maximum 180P away at the same axial location. The range of rib gaps is spanned in a single test section, as it would be also in a reactor assembly. As a result of these effects, flow regime maps obtained by other researchers for downflow in annuli are not accurate for defining flow regimes in a ribbed annulus. Flow regime transitions similar to those noted by, e.g., Bamea, were observed; the locations of these transitions were displaced with respect to the transition equations derived by Bamea. Experimental bubble rise velocity measurements were also obtained in the same test section. The bubble rise velocities were much higher than expected from the theory developed for slug bubbles in tubes, unribbed annuli, and rectangular channels. An elliptical-cap bubble rises faster than a slug bubble of the same area. Large, slug-shaped bubbles injected into the test section were observed to reduce in size as they rose, due to interaction with a longitudinal rib. They thereby adopted a shape more like an elliptical-cap bubble, hence rising faster than the original slug bubble.

  10. Flow regime mapping of vertical two-phase downflow in a ribbed annulus

    SciTech Connect (OSTI)

    Kielpinski, A.L.

    1992-01-01T23:59:59.000Z

    Two-phase flow regimes have been mapped for vertical, cocurrent downflow in a narrow annulus which is partially segmented by the presence of longitudinal ribs. This geometry and flow condition has application to the analysis of a Large-Break Loss of Coolant Accident (LB-LOCA) in the production K-Reactor at the Savannah River Site (SRS). The ribbed annular geometry, particularly the presence of non-sealing ribs, gives rise to some unique phenomenological features. The flow behavior is influenced by the partial segmentation of the annulus into four quadrants or subchannels. A random element is induced by the natural bowing of the slender tubes; the width of the azimuthal flow path between two subchannels at a given axial location is indeterminate, and can take on any value between zero and the maximum clearance of 7.6 [times] l0[sup [minus]4] m. When the rib gap is zero at a given location, it is at a maximum 180P away at the same axial location. The range of rib gaps is spanned in a single test section, as it would be also in a reactor assembly. As a result of these effects, flow regime maps obtained by other researchers for downflow in annuli are not accurate for defining flow regimes in a ribbed annulus. Flow regime transitions similar to those noted by, e.g., Bamea, were observed; the locations of these transitions were displaced with respect to the transition equations derived by Bamea. Experimental bubble rise velocity measurements were also obtained in the same test section. The bubble rise velocities were much higher than expected from the theory developed for slug bubbles in tubes, unribbed annuli, and rectangular channels. An elliptical-cap bubble rises faster than a slug bubble of the same area. Large, slug-shaped bubbles injected into the test section were observed to reduce in size as they rose, due to interaction with a longitudinal rib. They thereby adopted a shape more like an elliptical-cap bubble, hence rising faster than the original slug bubble.

  11. Ricci flow and quantum theory

    E-Print Network [OSTI]

    Robert Carroll

    2007-11-05T23:59:59.000Z

    We show some relations between Ricci flow and quantum theory via Fisher information and the quantum potential.

  12. Progress in Grid Scale Flow Batteries

    E-Print Network [OSTI]

    2011Year #12;Flow Battery Research at PNNL and Sandia #12 with industries and universities New Generation Redox Flow Batteries, PNNL Developed new generation redox flow

  13. A Uniform Type Structure for Secure Information KOHEI HONDA

    E-Print Network [OSTI]

    Gay, Simon

    A Uniform Type Structure for Secure Information Flow KOHEI HONDA Queen Mary, University of London . . . . . . . . . . . . . . . . . 13 Author's address: K. Honda, Department of Computer Science, Queen Mary, University of London, Mile, Vol. TBD, No. TDB, Month Year, Pages 1--83. #12; 2 · Kohei Honda and Nobuko Yoshida 2.5 Linear

  14. Type curve analysis for naturally fractured reservoirs (infinite-acting reservoir case): a new approach

    E-Print Network [OSTI]

    Angel Restrepo, Juan Alejandro

    2000-01-01T23:59:59.000Z

    This work introduces new type curve solutions for an unfractured well in an infinite-acting naturally fractured reservoir, including wellbore storage and skin effects. Both pseudosteady-state¹ and transient²?³ interporosity flow models are studied...

  15. The Big Flow

    E-Print Network [OSTI]

    P. Sikivie

    2001-12-04T23:59:59.000Z

    The late infall of cold dark matter onto an isolated galaxy, such as our own, produces streams and caustics in its halo. The outer caustics are topological spheres whereas the inner caustics are rings. The self-similar model of galactic halo formation predicts that the caustic ring radii $a_n$ follow the approximate law $a_n \\sim 1/n$. In a study of 32 extended and well-measured external galactic rotation curves evidence was found for this law. In the case of the Milky Way, the locations of eight sharp rises in the rotation curve fit the prediction of the self-similar model at the 3% level. Moreover, a triangular feature in the IRAS map of the galactic plane is consistent with the imprint of a ring caustic upon the baryonic matter. These observations imply that the dark matter in our neighborhood is dominated by a single flow. Estimates of that flow's density and velocity vector are given.

  16. Structural power flow measurement

    SciTech Connect (OSTI)

    Falter, K.J.; Keltie, R.F.

    1988-12-01T23:59:59.000Z

    Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

  17. ANL-85-51 ANL-85-51 FLOW-INDUCED VIBRATION OF CIRCULAR CYLINDRICAL...

    Office of Scientific and Technical Information (OSTI)

    leakage signaled the beginning of a troublesome period for a series of 1-3 Table i.l U.S. Power Reactor Field Experience with Flow-induced Vibration Year Reactor Type Component...

  18. A Theory of Information-Flow Labels Beno^it Montagu

    E-Print Network [OSTI]

    Pollack, Randy

    Star; Asbestos. I. INTRODUCTION Information-flow control (IFC) systems [1] run the gamut from static type systems for information-flow control, each with some set of labels encoding security policies that can be attached to data of programs in a small lambda-calculus parameterized over an arbitrary label algebra. We use this framework

  19. CFD Simulation and Experimental Testing of Multiphase Flow Inside the MVP Electrical Submersible Pump

    E-Print Network [OSTI]

    Rasmy Marsis, Emanuel 1983-

    2012-08-16T23:59:59.000Z

    The MVP is a special type of Electrical Submersible Pumps (ESPs) manufactured by Baker Hughes, model no. G470, and is capable of handling multiphase flow up to 70% Gas Volume Fraction (GVF). Flows at high GVF cause conventional ESPs to surge...

  20. A justification for the thin film approximation of Stokes flow with surface tension

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    A justification for the thin film approximation of Stokes flow with surface tension M. G¨unther 1.prokert@tue.nl Abstract In the free boundary problem of Stokes flow driven by surface tension, we pass to the limit by surface tension is considered, the type of the problem changes significantly: while in the general case

  1. A three-dimensional analysis of the flow and heat transfer for the modified chemical vapor deposition process including buoyancy, variable properties, and tube rotation

    SciTech Connect (OSTI)

    Lin, Y.T.; Choi, M.; Greif, R. (Univ. of California, Berkeley (USA))

    1991-05-01T23:59:59.000Z

    A study has been made of the heat transfer, flow, and particle deposition relative to the modified chemical vapor deposition (MCVD) process. The effects of variable properties, buoyancy, and tube rotation have been included in the study. The resulting three-dimensional temperature and velocity fields have been obtained for a range of conditions. The effects of buoyancy result in asymmetric temperature and axial velocity profiles with respect to the tube axis. Variable properties cause significant variations in the axial velocity along the tube and in the secondary flow in the region near the torch. Particle trajectories are shown to be strongly dependent on the tube rotation and are helices for large rotational speeds. The component of secondary flow in the radial direction is compared to the thermophoretic velocity, which is the primary cause of particle deposition in the MCVD process. Over the central portion of the tube the radial component of the secondary flow is most important in determining the motion of the particles.

  2. Nuclear Instruments and Methods in Physics Research A 547 (2005) 663678 Determining axial fuel-rod power-density profiles from in-core

    E-Print Network [OSTI]

    Shultis, J. Kenneth

    is proposed for determining power-density profiles in nuclear reactor fuel rods from neutron flux measurementsNuclear Instruments and Methods in Physics Research A 547 (2005) 663­678 Determining axial fuel-rod power-density profiles from in-core neutron flux measurements J. Kenneth Shultis� Department

  3. Anderson-Gregory; Constable-Steven; Orcutt-John; Staudigel-Hubert; Tolstoy-Maya; Wyatt-Frank-K, Observing seafloor tilt on Axial Segment, Juan de Fuca Ridge. Eos, Transactions, American Geophysical

    E-Print Network [OSTI]

    Menke, William

    -Frank-K, Observing seafloor tilt on Axial Segment, Juan de Fuca Ridge. Eos, Transactions, American Geophysical Union de Fuca Ridge. Geophysical Research Letters.22; 2, Pages 147-150. 1995. Baker-Edward-T; Fox eruption of Axial Volcano, Juan de Fuca Ridge. Geophysical Research Letters.26; 23, Pages 3445-3448. 1999

  4. GaAs Nanowire Array Solar Cells with Axial p-i-n Junctions Maoqing Yao, Ningfeng Huang, Sen Cong, Chun-Yung Chi, M. Ashkan Seyedi, Yen-Ting Lin, Yu Cao,

    E-Print Network [OSTI]

    Zhou, Chongwu

    for future low-cost, high-efficiency photovoltaics. KEYWORDS: Nanowires, solar cells, gallium arsenide, axial.58% efficiency. Simulations show that axial junctions are more tolerant to doping variation than radial junctions and shallow junctions are essential for a high extraction efficiency. Our approach opens up great opportunity

  5. Development of a J-estimation scheme for internal circumferential and axial surface cracks in elbows

    SciTech Connect (OSTI)

    Mohan, R.; Brust, F.W.; Ghadiali, N.; Wilkowski, G.

    1996-06-01T23:59:59.000Z

    This report summarizes efforts to develop elastic and elastic-plastic fracture mechanics analyses for internal surface cracks in elbows. The analyses involved development of a GE/EPRI type J-estimation scheme which requires an elastic and fully plastic contribution to crack-driving force in terms of the J-integral parameter. The elastic analyses require the development of F-function values to relate the J{sub e} term to applied loads. Similarly, the fully plastic analyses require the development of h-functions to relate the J{sub p} term to the applied loads. The F- and h-functions were determined from a matrix of finite element analyses. To minimize the cost of the analyses, three-dimensional ABAQUS finite element analyses were compared to a simpler finite element technique called the line-spring method. The line-spring method provides a significant computational savings over the full three-dimensional analysis. The comparison showed excellent agreement between the line-spring and three-dimensional analysis. This experience was consistent with comparisons with circumferential surface-crack analyses in straight pipes during the NRC`s Short Cracks in Piping and Piping Welds program.

  6. Innovation flow through social networks: Productivity distribution

    E-Print Network [OSTI]

    T. Di Matteo; T. Aste; M. Gallegati

    2004-06-19T23:59:59.000Z

    A detailed empirical analysis of the productivity of non financial firms across several countries and years shows that productivity follows a non-Gaussian distribution with power law tails. We demonstrate that these empirical findings can be interpreted as consequence of a mechanism of exchanges in a social network where firms improve their productivity by direct innovation or/and by imitation of other firm's technological and organizational solutions. The type of network-connectivity determines how fast and how efficiently information can diffuse and how quickly innovation will permeate or behaviors will be imitated. From a model for innovation flow through a complex network we obtain that the expectation values of the productivity level are proportional to the connectivity of the network of links between firms. The comparison with the empirical distributions reveals that such a network must be of a scale-free type with a power-law degree distribution in the large connectivity range.

  7. Complex Flow Workshop Report

    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, 2012 University

  8. Non-axisymmetric Flows

    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 Renewable Energy:Nanowire Solar541,9337,2AprilBig EddyNobelNon-axisymmetric Flows and

  9. accretion disk flows: Topics by E-print Network

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

    appear for wide generic conditions. A reference run is shown in detail, with a wind leaving the computational volume in the axial direction with a poloidal velocity equal...

  10. Radial flow heat exchanger

    DOE Patents [OSTI]

    Valenzuela, Javier (Hanover, NH)

    2001-01-01T23:59:59.000Z

    A radial flow heat exchanger (20) having a plurality of first passages (24) for transporting a first fluid (25) and a plurality of second passages (26) for transporting a second fluid (27). The first and second passages are arranged in stacked, alternating relationship, are separated from one another by relatively thin plates (30) and (32), and surround a central axis (22). The thickness of the first and second passages are selected so that the first and second fluids, respectively, are transported with laminar flow through the passages. To enhance thermal energy transfer between first and second passages, the latter are arranged so each first passage is in thermal communication with an associated second passage along substantially its entire length, and vice versa with respect to the second passages. The heat exchangers may be stacked to achieve a modular heat exchange assembly (300). Certain heat exchangers in the assembly may be designed slightly differently than other heat exchangers to address changes in fluid properties during transport through the heat exchanger, so as to enhance overall thermal effectiveness of the assembly.

  11. Event-shape fluctuations and flow correlations in ultra-relativistic heavy-ion collisions

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

    Jia, Jiangyong [Stony Brook Univ., NY (United States). Dept. of Chemistry; Brookhaven National Lab., Upton, NY (United States). Physics Dept.

    2014-12-01T23:59:59.000Z

    I review recent measurements of a large set of flow observables associated with event-shape fluctuations and collective expansion in heavy ion collisions. First, these flow observables are classified and experiment methods are introduced. The experimental results for each type of observables are then presented and compared to theoretical calculations. A coherent picture of initial condition and collective flow based on linear and non-linear hydrodynamic responses is derived, which qualitatively describe most experimental results. I discuss new types of fluctuation measurements that can further our understanding of the event-shape fluctuations and collective expansion dynamics.

  12. Magneto-Centrifugal Launching of Jets from Accretion Disks. I: Cold Axisymmetric Flows

    E-Print Network [OSTI]

    R. Krasnopolsky; Z. -Y. Li; R. D. Blandford

    1999-07-29T23:59:59.000Z

    The magneto-centrifugal model for jet formation is studied by time-dependent simulations reaching steady state in a cold gas with negligible fluid pressure, in an axisymmetric geometry, using a modification of the Zeus3D code adapted to parallel computers. The number of boundary conditions imposed at the coronal base takes into account the existence of the fast and Alfvenic critical surfaces, avoiding over-determination of the flow. The size and shape of the computational box is chosen to include these critical surfaces, reducing the influence of the outer boundary conditions. As there is a region, near the origin, where the inclination of field lines to the axis is too small to drive a centrifugal wind, we inject a thin, axial jet, expected to form electromagnetically near black holes. Acceleration and collimation appear for wide generic conditions. A reference run is shown in detail, with a wind leaving the computational volume in the axial direction with a poloidal velocity equal to 4 times the poloidal Alfven speed, collimated inside 11 degrees. Finally, the critical surfaces, fieldlines, thrust, energy, torque and mass discharge of the outgoing wind are shown for simulations with various profiles of mass and magnetic flux at the base of the corona.

  13. Magneto-Centrifugal Launching of Jets from Accretion Disks; 1, Cold Axisymmetric Flows

    E-Print Network [OSTI]

    Krasnopolsky, R; Blandford, R D

    1999-01-01T23:59:59.000Z

    The magneto-centrifugal model for jet formation is studied by time-dependent simulations reaching steady state in a cold gas with negligible fluid pressure, in an axisymmetric geometry, using a modification of the Zeus3D code adapted to parallel computers. The number of boundary conditions imposed at the coronal base takes into account the existence of the fast and Alfvenic critical surfaces, avoiding over-determination of the flow. The size and shape of the computational box is chosen to include these critical surfaces, reducing the influence of the outer boundary conditions. As there is a region, near the origin, where the inclination of field lines to the axis is too small to drive a centrifugal wind, we inject a thin, axial jet, expected to form electromagnetically near black holes. Acceleration and collimation appear for wide generic conditions. A reference run is shown in detail, with a wind leaving the computational volume in the axial direction with a poloidal velocity equal to 4 times the poloidal Al...

  14. Dust around Type Ia supernovae

    E-Print Network [OSTI]

    Wang, Lifan

    2005-01-01T23:59:59.000Z

    Dust around Type Ia supernovae Lifan Wang 1,2 LawrenceIa. Subject headings: Supernovae: General, Dust, Extinctionline) bands for Type Ia supernovae. (a), upper panel, shows

  15. Active combustion flow modulation valve

    DOE Patents [OSTI]

    Hensel, John Peter; Black, Nathaniel; Thorton, Jimmy Dean; Vipperman, Jeffrey Stuart; Lambeth, David N; Clark, William W

    2013-09-24T23:59:59.000Z

    A flow modulation valve has a slidably translating hollow armature with at least one energizable coil wound around and fixably attached to the hollow armature. The energizable coil or coils are influenced by at least one permanent magnet surrounding the hollow armature and supported by an outer casing. Lorentz forces on the energizable coils which are translated to the hollow armature, increase or decrease the flow area to provide flow throttling action. The extent of hollow armature translation depends on the value of current supplied and the direction of translation depends on the direction of current flow. The compact nature of the flow modulation valve combined with the high forces afforded by the actuator design provide a flow modulation valve which is highly responsive to high-rate input control signals.

  16. Wolter type i LAMAR

    SciTech Connect (OSTI)

    Catura, R.C.; Joki, E.G.

    1981-11-01T23:59:59.000Z

    Observational objectives for the LAMAR and their influence on the instrument design are discussed. It is concluded that the most important design parameter is the angular resolution of the LAMAR modules since it so strongly influences sensitivity, optical identifications, source confusion, spectral resolution for objective gratings and the ability to resolve small extended sources. A high resolution Wolter Type I LAMAR module is described, its hardware status discussed, and the performance of a LAMAR observatory presented. A promising technique for enhancing the reflectivity of Wolter Type I X-ray optics in a selected bandpass at high energy has been investigated and the performance of the LAMAR module, utilizing this method, has been calculated.

  17. Rappels: 4) Piles Types abstraits de donnes (Abstract Data Type)

    E-Print Network [OSTI]

    Hamel, Sylvie

    Rappels: 4) Piles #12;Types abstraits de données (Abstract Data Type) IFT2015, A2009, Sylvie Hamel Université de Montréal 1Piles Type de données Un ensemble de valeurs Un ensemble d'opérations Structure de Université de Montréal 2Piles #12;Type abstrait de données PILE (§4.2) Garde en mémoire des objets

  18. Subsurface Flow and Transport | EMSL

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

    subsurface related to contaminant transport, carbon cycling, enhanced oil recovery and carbon dioxide sequestration. See a complete list of Subsurface Flow and Transport...

  19. Geothermal loan guaranty cash flow model: description and users' manual

    SciTech Connect (OSTI)

    Keimig, M.A.; Rosenberg, J.I.; Entingh, D.J.

    1980-11-01T23:59:59.000Z

    This is the users guide for the Geothermal Loan Guaranty Cash Flow Model (GCFM). GCFM is a Fortran code which designs and costs geothermal fields and electric power plants. It contains a financial analysis module which performs life cycle costing analysis taking into account various types of taxes, costs and financial structures. The financial module includes a discounted cash flow feature which calculates a levelized breakeven price for each run. The user's guide contains descriptions of the data requirements and instructions for using the model.

  20. Rényi entropy flows from quantum heat engines

    E-Print Network [OSTI]

    Mohammad H. Ansari; Yuli V. Nazarov

    2015-03-20T23:59:59.000Z

    We evaluate Renyi entropy flows from generic quantum heat engines (QHE) to a weakly-coupled probe environment kept in thermal equilibrium. We show that the flows are determined not only by heat flow but also by a quantum coherent flow that can be separately measured in experiment apart from the heat flow measurement. The same pertains to Shanon entropy flow. This appeals for a revision of the concept of entropy flows in quantum nonequlibrium thermodynamics.

  1. Sample handling for kinetics and molecular assembly in flow cytometry

    SciTech Connect (OSTI)

    Sklar, L.A. [Los Alamos National Lab., NM (United States). National Flow Cytometry Resource]|[Univ. of New Mexico, Albuquerque, NM (United States). School of Medicine; Seamer, L.C.; Kuckuck, F.; Prossnitz, E.; Edwards, B. [Univ. of New Mexico, Albuquerque, NM (United States). School of Medicine; Posner, G. [Northern Arizona Univ., Flagstaff, AZ (United States). Dept. of Chemistry

    1998-07-01T23:59:59.000Z

    Flow cytometry discriminates particle associated fluorescence from the fluorescence of the surrounding medium. It permits assemblies of macromolecular complexes on beads or cells to be detected in real-time with precision and specificity. The authors have investigated two types of robust sample handling systems which provide sub-second resolution and high throughput: (1) mixers which use stepper-motor driven syringes to initiate chemical reactions in msec time frames; and (2) flow injection controllers with valves and automated syringes used in chemical process control. In the former system, the authors used fast valves to overcome the disparity between mixing 100 {micro}ls of sample in 100 msecs and delivering sample to a flow cytometer at 1 {micro}l/sec. Particles were detected within 100 msec after mixing, but turbulence was created which lasted for 1 sec after injection of the sample into the flow cytometer. They used optical criteria to discriminate particles which were out of alignment due to the turbulent flow. Complex sample handling protocols involving multiple mixing steps and sample dilution have also been achieved. With the latter system they were able to automate sample handling and delivery with intervals of a few seconds. The authors used a fluidic approach to defeat turbulence caused by sample introduction. By controlling both sheath and sample with individual syringes, the period of turbulence was reduced to {approximately} 200 msecs. Automated sample handling and sub-second resolution should permit broad analytical and diagnostic applications of flow cytometry.

  2. Opposed-flow virtual cyclone for particle concentration

    DOE Patents [OSTI]

    Rader, Daniel J. (Lafayette, CA); Torczynski, John R. (Albuquerque, NM)

    2000-12-05T23:59:59.000Z

    An opposed-flow virtual cyclone for aerosol collation which can accurately collect, classify, and concentrate (enrich) particles in a specific size range. The opposed-flow virtual cyclone is a variation on the virtual cyclone and has its inherent advantages (no-impact particle separation in a simple geometry), while providing a more robust design for concentrating particles in a flow-through type system. The opposed-flow virtual cyclone consists of two geometrically similar virtual cyclones arranged such that their inlet jets are inwardly directed and symmetrically opposed relative to a plane of symmetry located between the two inlet slits. A top plate bounds both jets on the "top" side of the inlets, while the other or lower wall curves "down" and away from each inlet jet. Each inlet jet will follow the adjacent lower wall as it turns away, and that particles will be transferred away from the wall and towards the symmetry plane by centrifugal action. After turning, the two jets merge smoothly along the symmetry line and flow parallel to it through the throat. Particles are transferred from the main flows, across a dividing streamline, and into a central recirculating region, where particle concentrations become greatly increased relative to the main stream.

  3. Dolomitization by ground-water flow systems in carbonate platforms

    SciTech Connect (OSTI)

    Simms, M.

    1984-09-01T23:59:59.000Z

    Dolomite occurs throughout the subsurface of modern carbonate platforms such as the Bahamas. Groundwater flow systems must be responsible for delivery of reactants needed for dolomitization. Reflux, freshwater lens flows, and thermal convection are large-scale flow systems that may be widespread in active platforms. The author has evaluated some aspects of the dynamics and characteristics of these processes with ground-water flow theory and by scaled sandbox experiments. Reflux is not restricted to hypersaline brines, but can occur with bankwaters of only slightly elevated salinity such as those found on the Bahama Banks today (42%). The lack of evaporites in a stratigraphic section, therefore, does not rule out the possibility that reflux may have operated. Flows associated with freshwater lenses include flow in the lens, in the mixing zone, and in the seawater beneath and offshore of the lens. Upward transfer of seawater through the platform margins occurs when surrounding cold ocean water migrates into the platform and is heated. This type of thermal convection (Kohout convection) has been studied by Francis Kohout in south Florida. The ranges of mass flux of magnesium in these processes are all comparable and are all sufficient to account for young dolomites beneath modern platforms. Each process yields dolomitized zones of characteristic shape and location and perhaps may be distinguishable in ancient rocks. The concepts presented here may have application to exploration for dolomite reservoirs in the Gulf Coast and elsewhere.

  4. Development of an equivalent homogenous fluid model for pseudo-two-phase (air plus water) flow through fractured rock

    SciTech Connect (OSTI)

    Price, J.; Indraratna, B. [University of Wollongong, Wollongong, NSW (Australia). School of Civil Engineering

    2005-07-01T23:59:59.000Z

    Fracture flow of two-phase mixtures is particularly applicable to the coal mining and coal bed methane projects in Australia. A one-dimensional steady-state pseudo-two-phase flow model is proposed for fractured rock. The model considers free flow of a compressible mixture of air and water in an inclined planar fracture and is based upon the conservation of momentum and the 'cubic' law. The flow model is coupled to changes in the stress environment through the fracture normal stiffness, which is related to changes in fracture aperture. The model represents the individual air and water phases as a single equivalent homogenous fluid. Laboratory testing was performed using the two-phase high-pressure triaxial apparatus on 54 mm diameter (approximately 2: 1 height: diameter) borehole cores intersected by induced near-axial fractures. The samples were of Triassic arenaceous fine-medium grained sandstone (known as the Eckersley Formation) that is found locally in the Southern Coalfield of New South Wales. The sample fracture roughness was assessed using a technique based upon Fourier series analysis to objectively attribute a joint roughness coefficient. The proposed two-phase flow model was verified using the recorded laboratory data obtained over a range of triaxial confining pressures (i.e., fracture normal stresses).

  5. TREAT experimental data base regarding fuel dispersals in LMFBR loss-of-flow accidents

    SciTech Connect (OSTI)

    Simms, R.; Fink, C.L.; Stanford, G.S.; Regis, J.P.

    1981-01-01T23:59:59.000Z

    The reactivity feedback from fuel relocation is a central issue in the analysis of loss-of-flow (LOF) accidents in LMFBRs. Fuel relocation has been studied in a number of LOF simulations in the TREAT reactor. In this paper the results of these tests are analyzed, using, as the principal figure of merit, the changes in equivalent fuel worth associated with the fuel motion. The equivalent fuel worth was calculated from the measured axial fuel distributions by weighting the data with a typical LMFBR fuel-worth function. At nominal power, the initial fuel relocation resulted in increases in equivalent fuel worth. Above nominal power the fuel motion was dispersive, but the dispersive driving forces could not unequivocally be identified from the experimental data.

  6. Arrangement for measuring the field angle of a magnetic field as a function of axial position within a magnet bore tube

    DOE Patents [OSTI]

    Pidcoe, Stephen V. (Bonita, CA); Zink, Roger A. (Desoto, TX); Boroski, William N. (Aurora, IL); McCaw, William R. (Burr Ridge, IL)

    1993-01-01T23:59:59.000Z

    An arrangement for measuring the field angle of a magnetic field as a function of axial position within a magnet bore tube of a magnet such as is used with the Superconducting Super Collider (SSC). The arrangement includes a magnetic field alignment gauge that is carried through the magnet bore tube by a positioning shuttle in predetermined increments. The positioning shuttle includes an extensible body assembly which is actuated by an internal piston arrangement. A pair of spaced inflatable cuffs are carried by the body assembly and are selectively actuated in cooperation with pressurizing of the piston to selectively drive the positioning shuttle in an axial direction. Control of the shuttle is provided by programmed electronic computer means located exteriorly of the bore tube and which controls valves provided pressurized fluid to the inflatable cuss and the piston arrangement.

  7. Instability of wave modes in a two-stream free-electron laser with a helical wiggler and an axial magnetic field

    SciTech Connect (OSTI)

    Mohsenpour, Taghi; Mehrabi, Narges [Department of Physics, Faculty of Basic Sciences, University of Mazandaran, Babolsar (Iran, Islamic Republic of)] [Department of Physics, Faculty of Basic Sciences, University of Mazandaran, Babolsar (Iran, Islamic Republic of)

    2013-08-15T23:59:59.000Z

    The dispersion relation of a two-stream free-electron laser (TSFEL) with a one-dimensional helical wiggler and an axial magnetic field is studied. Also, all relativistic effects on the space-charge wave and radiation are considered. This dispersion relation is solved numerically to find the unstable interaction among the all wave modes. Numerical calculations show that the growth rate is considerably enhanced in comparison with single-stream FEL. The effect of the velocity difference of the two electron beams on the two-stream instability and the FEL resonance is investigated. The maximum growth rate of FEL resonance is investigated numerically as a function of the axial magnetic field.

  8. Postdoc Appointment Types

    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 forPortsmouth/Paducah Project Office Press ReleasesPost-Closure BenefitsAppointment Types

  9. Network Flow Optimization under Uncertainty

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    Network model in words Minimize the cost of satisfying demands for electric energy By: imports, exports and electricity Subject to: conservation of energy flows (net after losses), lower and upper bounds on flows is a reactive approach: how would the optimal solution have changed if I'd only known? · Proactive approaches

  10. Redox Flow Batteries, a Review

    SciTech Connect (OSTI)

    U. Tennessee Knoxville; U. Texas Austin; McGill U; Weber, Adam Z.; Mench, Matthew M.; Meyers, Jeremy P.; Ross, Philip N.; Gostick, Jeffrey T.; Liu, Qinghua

    2011-07-15T23:59:59.000Z

    Redox flow batteries are enjoying a renaissance due to their ability to store large amounts of electrical energy relatively cheaply and efficiently. In this review, we examine the components of redox flow batteries with a focus on understanding the underlying physical processes. The various transport and kinetic phenomena are discussed along with the most common redox couples.

  11. Wavy flow cooling concept for turbine airfoils

    DOE Patents [OSTI]

    Liang, George (Palm City, FL)

    2010-08-31T23:59:59.000Z

    An airfoil including an outer wall and a cooling cavity formed therein. The cooling cavity includes a leading edge flow channel located adjacent a leading edge of the airfoil and a trailing edge flow channel located adjacent a trailing edge of the airfoil. Each of the leading edge and trailing edge flow channels define respective first and second flow axes located between pressure and suction sides of the airfoil. A plurality of rib members are located within each of the flow channels, spaced along the flow axes, and alternately extending from opposing sides of the flow channels to define undulating flow paths through the flow channels.

  12. Vertical flow chemical detection portal

    DOE Patents [OSTI]

    Linker, K.L.; Hannum, D.W.; Conrad, F.J.

    1999-06-22T23:59:59.000Z

    A portal apparatus is described for screening objects or persons for the presence of trace amounts of chemical substances such as illicit drugs or explosives. The apparatus has a test space, in which a person may stand, defined by two generally upright sides spanned by a horizontal transom. One or more fans in the transom generate a downward air flow (uni-directional) within the test space. The air flows downwardly from a high pressure upper zone, past the object or person to be screened. Air moving past the object dislodges from the surface thereof both volatile and nonvolatile particles of the target substance. The particles are entrained into the air flow which continues flowing downward to a lower zone of reduced pressure, where the particle-bearing air stream is directed out of the test space and toward preconcentrator and detection components. The sides of the portal are specially configured to partially contain and maintain the air flow. 3 figs.

  13. Recurrent flow analysis in spatiotemporally chaotic 2-dimensional Kolmogorov flow

    E-Print Network [OSTI]

    Dan Lucas; Rich Kerswell

    2015-04-01T23:59:59.000Z

    Motivated by recent success in the dynamical systems approach to transitional flow, we study the efficiency and effectiveness of extracting simple invariant sets (recurrent flows) directly from chaotic/turbulent flows and the potential of these sets for providing predictions of certain statistics of the flow. Two-dimensional Kolmogorov flow (the 2D Navier-Stokes equations with a sinusoidal body force) is studied both over a square [0, 2{\\pi}]2 torus and a rectangular torus extended in the forcing direction. In the former case, an order of magnitude more recurrent flows are found than previously (Chandler & Kerswell 2013) and shown to give improved predictions for the dissipation and energy pdfs of the chaos via periodic orbit theory. Over the extended torus at low forcing amplitudes, some extracted states mimick the statistics of the spatially-localised chaos present surprisingly well recalling the striking finding of Kawahara & Kida (2001) in low-Reynolds-number plane Couette flow. At higher forcing amplitudes, however, success is limited highlighting the increased dimensionality of the chaos and the need for larger data sets. Algorithmic developments to improve the extraction procedure are discussed.

  14. Method for generating extreme ultraviolet with mather-type plasma accelerators for use in Extreme Ultraviolet Lithography

    DOE Patents [OSTI]

    Hassanein, Ahmed (Bolingbrook, IL); Konkashbaev, Isak (Bolingbrook, IL)

    2006-10-03T23:59:59.000Z

    A device and method for generating extremely short-wave ultraviolet electromagnetic wave uses two intersecting plasma beams generated by two plasma accelerators. The intersection of the two plasma beams emits electromagnetic radiation and in particular radiation in the extreme ultraviolet wavelength. In the preferred orientation two axially aligned counter streaming plasmas collide to produce an intense source of electromagnetic radiation at the 13.5 nm wavelength. The Mather type plasma accelerators can utilize tin, or lithium covered electrodes. Tin, lithium or xenon can be used as the photon emitting gas source.

  15. Flow Rate Measurements Using Flow-Induced Pipe Vibration

    SciTech Connect (OSTI)

    R. P. Evans; Jonathan D. Blotter; Alan G. Stephens

    2004-03-01T23:59:59.000Z

    This paper focuses on the possibility of a non-intrusive, low cost, flow rate measurement technique. The technique is based on signal noise from an accelerometer attached to the surface of the pipe. The signal noise is defined as the standard deviation of the frequency averaged time series signal. Experimental results are presented that indicate a nearly quadratic relationship between the signal noise and mass flow rate in the pipe. It is also shown that the signal noise - flow rate relationship is dependant on the pipe material and diameter.

  16. Speed-up of combustion fronts in shear flows

    E-Print Network [OSTI]

    Hamel, Francois

    2011-01-01T23:59:59.000Z

    This paper is concerned with the analysis of speed-up of reaction-diffusion-advection traveling fronts in infinite cylinders with periodic boundary conditions. The advection is a shear flow with a large amplitude and the reaction is nonnegative, with either positive or zero ignition temperature. The unique or minimal speeds of the traveling fronts are proved to be asymptotically linear in the flow amplitude as the latter goes to infinity, solving an open problem from \\cite{b}. The asymptotic growth rate is characterized explicitly as the unique or minimal speed of traveling fronts for a limiting degenerate problem, and the convergence of the regular traveling fronts to the degenerate ones is proved for positive ignition temperatures under an additional H{\\"{o}}rmander-type condition on the flow.

  17. Rappels: 4) Piles Types abstraits de donnes (Abstract Data Type)

    E-Print Network [OSTI]

    Hamel, Sylvie

    Rappels: 4) Piles Types abstraits de données (Abstract Data Type) IFT2015, A2009, Sylvie Hamel Université de Montréal 1Piles Type de données Un ensemble de valeurs Un ensemble d'opérations Structure de Université de Montréal 2Piles Type abstrait de données PILE (§4.2) Garde en mémoire des objets arbitraires

  18. Ceramic Cross Flow Recuperator Design Parameters

    E-Print Network [OSTI]

    Gonzalez, J. M.; Rebello, W. J.

    1981-01-01T23:59:59.000Z

    the performance of the ceramic recuperator in various industrial furnaces. The ceramic cross flow recuperator core has multiple rectangular flow passages (perpendicular to each other) for the air and gas. Various flow passages are available contingent upon...

  19. 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 ...

  20. Insertable fluid flow passage bridgepiece and method

    DOE Patents [OSTI]

    Jones, Daniel O. (Glenville, NV)

    2000-01-01T23:59:59.000Z

    A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.

  1. Boost type PWM HVDC transmission system

    SciTech Connect (OSTI)

    Ooi, B.T.; Wang, X. (McGill Univ., Montreal, PQ (Canada). Dept. of Electrical Engineering)

    1991-10-01T23:59:59.000Z

    This paper reports that conventional HVdc is built around the mercury arc rectifier or the thyristor which requires line commutation. The advances of fast, high power GTO's and future devices such as MCT's with turn off capabilities, are bringing PWM techniques within the range of HVdc applications. By combining PWM techniques to the boost type bridge topology, one has an alternate system of HVdc Transmission. On the ac side, the converter station has active controls over: the voltage amplitude, the voltage angle and the frequency. On the dc side, parallel connections facilitate multi-terminal load sharing by simple local controls so that redundant communication channels are not required. Bidirectional power through each station is accomplished by the reversal of the direction of dc current flow. These claims have been substantiated by experimental results from laboratory size multi-terminal models.

  2. Flow distribution channels to control flow in process channels

    DOE Patents [OSTI]

    Tonkovich, Anna Lee; Arora, Ravi; Kilanowski, David

    2014-10-28T23:59:59.000Z

    The invention describes features that can be used to control flow to an array of microchannels. The invention also describes methods in which a process stream is distributed to plural microchannels.

  3. The transition from two phase bubble flow to slug flow

    E-Print Network [OSTI]

    Radovcich, Nick A.

    1962-01-01T23:59:59.000Z

    The process of transition from bubble to slug flow in a vertical pipe has been studied analytically and experimentally. An equation is presented which gives the agglomeration time as a function of void fraction, channel ...

  4. Thermocapillary Flow on Superhydrophobic Surfaces

    E-Print Network [OSTI]

    Baier, Tobias; Hardt, Steffen

    2010-01-01T23:59:59.000Z

    A liquid in Cassie-Baxter state above a structured superhydrophobic surface is ideally suited for surface driven transport due to its large free surface fraction in close contact to a solid. We investigate thermal Marangoni flow over a superhydrophobic array of fins oriented parallel or perpendicular to an applied temperature gradient. In the Stokes limit we derive an analytical expression for the bulk flow velocity above the surface and compare it with numerical solutions of the Navier-Stokes equation. Even for moderate temperature gradients comparatively large flow velocities are induced, suggesting to utilize this principle for microfluidic pumping.

  5. Between global flows & territorial control : the state, tourism development, and the politics of reterritorialization in the Middle East

    E-Print Network [OSTI]

    Hazbun, Waleed (Waleed Albert), 1968-

    2002-01-01T23:59:59.000Z

    This dissertation presents a new type of theory about the impact of increased transnational capital flows on state building processes. Most of the political science literature about globalization has been focused on debating ...

  6. Mechanism design with approximate types

    E-Print Network [OSTI]

    Zhu, Zeyuan Allen

    2012-01-01T23:59:59.000Z

    In mechanism design, we replace the strong assumption that each player knows his own payoff type exactly with the more realistic assumption that he knows it only approximately: each player i only knows that his true type ...

  7. Types of Farming in Texas.

    E-Print Network [OSTI]

    Bonnen, C. A.

    1960-01-01T23:59:59.000Z

    .......... .......-.----------------------. 8 Labor -..-.....-----...------------------------------------------------. 9 Land Tenure .--.----....---....--------------------------------- 9 Number and Size of Farms ....----...----.-._--------- 10 Capital... -------------...-------.---------------------------- 21 Hogs -......-....--------------------------------------------------- 22 Poultry .-.---.-.....--.-..------.---------------------------------- 22 Horses and Mules ---..-....---..--..------------------------ 23 Types of Farming and Type-of-farming...

  8. Chaotic Transport in Planar Periodic Vortical Flows

    E-Print Network [OSTI]

    Taehoon Ahn; Seunghwan Kim

    1993-09-24T23:59:59.000Z

    We have studied a chaotic transport in a two-dimensional periodic vortical flow under a time-dependent perturbation with period T where the global diffusion occurs along the stochastic web. By using the Melnikov method we construct the separatrix map describing the approximate dynamics near the saddle separatrices. Focusing on the small T, the width of the stochastic layer is calculated analytically by using the residue criterion and the diffusion constant by using the random phase assumption and correlated random walks. The analytical results are in good agreements with the results of two different types of numerical simulations by integrations of the Hamilton's equation of motion and by iterations of the separatrix map, which establishes the validity of the use of the separatrix map.

  9. Combustion dynamics in steady compressible flows

    E-Print Network [OSTI]

    S. Berti; D. Vergni; A. Vulpiani

    2008-07-03T23:59:59.000Z

    We study the evolution of a reactive field advected by a one-dimensional compressible velocity field and subject to an ignition-type nonlinearity. In the limit of small molecular diffusivity the problem can be described by a spatially discretized system, and this allows for an efficient numerical simulation. If the initial field profile is supported in a region of size l < lc one has quenching, i.e., flame extinction, where lc is a characteristic length-scale depending on the system parameters (reacting time, molecular diffusivity and velocity field). We derive an expression for lc in terms of these parameters and relate our results to those obtained by other authors for different flow settings.

  10. Hamiltonian Thermostats Fail to Promote Heat Flow

    E-Print Network [OSTI]

    Wm. G. Hoover; Carol G. Hoover

    2013-07-16T23:59:59.000Z

    Hamiltonian mechanics can be used to constrain temperature simultaneously with energy. We illustrate the interesting situations that develop when two different temperatures are imposed within a composite Hamiltonian system. The model systems we treat are "phi-4" chains, with quartic tethers and quadratic nearest-neighbor Hooke's-law interactions. This model is known to satisfy Fourier's law. Our prototypical problem sandwiches a Newtonian subsystem between hot and cold Hamiltonian reservoir regions. We have characterized four different Hamiltonian reservoir types. There is no tendency for any of these two-temperature Hamiltonian simulations to transfer heat from the hot to the cold degrees of freedom. Evidently steady heat flow simulations require energy sources and sinks, and are therefore incompatible with Hamiltonian mechanics.

  11. Colorado: Isothermal Battery Calorimeter Quantifies Heat Flow...

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

    Isothermal Battery Calorimeter Quantifies Heat Flow, Helps Make Safer, Longer-lasting Batteries Colorado: Isothermal Battery Calorimeter Quantifies Heat Flow, Helps Make Safer,...

  12. Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling...

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

    Nozzle Flow, Spray, Combustion, & Emission Modeling using KH-ACT Primary Breakup Model & Detailed Chemistry Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling using...

  13. Automation of radiochemical analysis by applying flow

    E-Print Network [OSTI]

    Sánchez, David

    of detection systems, including scintillation counting, a-spectrometers, proportional counters, mass spectrometry and spectrophotometry. ª 2010 Published by Elsevier Ltd. Keywords: Flow-analysis technique; Flow

  14. Minimum Stream Flow Standards (Connecticut)

    Broader source: Energy.gov [DOE]

    These regulations apply to all dams and structures which impound or divert waters on rivers or their tributaries, with some exceptions. The regulations set standards for minimum flow (listed in the...

  15. Nodes, modes and flow codes

    SciTech Connect (OSTI)

    Karniadakis, G.E.; Orszag, S.A. (Princeton Univ., NJ (United States))

    1993-03-01T23:59:59.000Z

    Computational fluid dynamics and the numerical prediction of fluid flow in the understanding and modeling of turbulence is discussed with emphasis on the development of direct numerical simulation (DNS) of high-Reynolds number turbulent flows. Recent advances in computer systems and their use in turbulence simulation are reviewed and the need for parallel processing to achieve teraflop speeds necessary for DNS is discussed. Computer system architectures, nodes, and parallel computers currently in use are reviewed. Spectral, spectral-element, particle, and hybrid difference methods of solving incompressible- and compressible-flow problems are examined. Four applications of parallel computers to turbulent flow problems are presented and future developments in computer systems are discussed. 24 refs.

  16. Miniaturized flow injection analysis system

    DOE Patents [OSTI]

    Folta, James A. (Livermore, CA)

    1997-01-01T23:59:59.000Z

    A chemical analysis technique known as flow injection analysis, wherein small quantities of chemical reagents and sample are intermixed and reacted within a capillary flow system and the reaction products are detected optically, electrochemically, or by other means. A highly miniaturized version of a flow injection analysis system has been fabricated utilizing microfabrication techniques common to the microelectronics industry. The microflow system uses flow capillaries formed by etching microchannels in a silicon or glass wafer followed by bonding to another wafer, commercially available microvalves bonded directly to the microflow channels, and an optical absorption detector cell formed near the capillary outlet, with light being both delivered and collected with fiber optics. The microflow system is designed mainly for analysis of liquids and currently measures 38.times.25.times.3 mm, but can be designed for gas analysis and be substantially smaller in construction.

  17. Message Flow Modulator Final Report

    E-Print Network [OSTI]

    Boyer, Robert Stephen

    operational environment at the Patuxent River Naval Air Test Center with scenarios developed by an independent in testing and demonstrating the flow modulator at the Patuxent River Naval Air Test Center. #12; MESSAGE

  18. Capillary flows in flexible structures

    E-Print Network [OSTI]

    Hoberg, Theresa B. (Theresa Blinn)

    2013-01-01T23:59:59.000Z

    Interactions between capillary and elastic effects are relevant to a variety of applications, from micro- and nano-scale manufacturing to biological systems. In this thesis, we investigate capillary flows in extremely ...

  19. Mechanical design of flow batteries

    E-Print Network [OSTI]

    Hopkins, Brandon J. (Brandon James)

    2013-01-01T23:59:59.000Z

    The purpose of this research is to investigate the design of low-cost, high-efficiency flow batteries. Researchers are searching for next-generation battery materials, and this thesis presents a systems analysis encompassing ...

  20. 2007 Estimated International Energy Flows

    SciTech Connect (OSTI)

    Smith, C A; Belles, R D; Simon, A J

    2011-03-10T23:59:59.000Z

    An energy flow chart or 'atlas' for 136 countries has been constructed from data maintained by the International Energy Agency (IEA) and estimates of energy use patterns for the year 2007. Approximately 490 exajoules (460 quadrillion BTU) of primary energy are used in aggregate by these countries each year. While the basic structure of the energy system is consistent from country to country, patterns of resource use and consumption vary. Energy can be visualized as it flows from resources (i.e. coal, petroleum, natural gas) through transformations such as electricity generation to end uses (i.e. residential, commercial, industrial, transportation). These flow patterns are visualized in this atlas of 136 country-level energy flow charts.

  1. particle flow for nonlinear filters

    E-Print Network [OSTI]

    Dobigeon, Nicolas

    particle flow for nonlinear filters Fred Daum 19 June 2012 Copyright © 2012 Raytheon Company. All rights reserved. Customer Success Is Our Mission is a trademark of Raytheon Company. 1 #12;discrete time

  2. Multiscale modeling in granular flow

    E-Print Network [OSTI]

    Rycroft, Christopher Harley

    2007-01-01T23:59:59.000Z

    Granular materials are common in everyday experience, but have long-resisted a complete theoretical description. Here, we consider the regime of slow, dense granular flow, for which there is no general model, representing ...

  3. Field Flows of Dark Energy

    E-Print Network [OSTI]

    Cahn, Robert N.

    2010-01-01T23:59:59.000Z

    Field Flows of Dark Energy Robert N. Cahn, Roland de Putter,July 8, 2008) Scalar ?eld dark energy evolving from a longthe key aspects of the dark energy evolution during much of

  4. Longitudinal dispersion in vegetated flow

    E-Print Network [OSTI]

    Murphy, Enda

    2006-01-01T23:59:59.000Z

    Vegetation is ubiquitous in rivers, estuaries and wetlands, strongly influencing both water conveyance and mass transport. The plant canopy affects both mean and turbulent flow structure, and thus both advection and ...

  5. Subcooled flow boiling of fluorocarbons

    E-Print Network [OSTI]

    Murphy, Richard Walter

    1971-01-01T23:59:59.000Z

    A study was conducted of heat transfer and hydrodynamic behavior for subcooled flow boiling of Freon-113, one of a group of fluorocarbons suitable for use in cooling of high-power-density electronic components. Problems ...

  6. A dependent nominal type theory

    E-Print Network [OSTI]

    Cheney, James

    2012-01-01T23:59:59.000Z

    Nominal abstract syntax is an approach to representing names and binding pioneered by Gabbay and Pitts. So far nominal techniques have mostly been studied using classical logic or model theory, not type theory. Nominal extensions to simple, dependent and ML-like polymorphic languages have been studied, but decidability and normalization results have only been established for simple nominal type theories. We present a LF-style dependent type theory extended with name-abstraction types, prove soundness and decidability of beta-eta-equivalence checking, discuss adequacy and canonical forms via an example, and discuss extensions such as dependently-typed recursion and induction principles.

  7. Type-IV Pilus Deformation Can Explain Retraction Behavior

    E-Print Network [OSTI]

    Ranajay Ghosh; Aloke Kumar; Ashkan Vaziri

    2014-09-18T23:59:59.000Z

    Polymeric filament like type IV Pilus (TFP) can transfer forces in excess of 100pN during their retraction before stalling, powering surface translocation(twitching). Single TFP level experiments have shown remarkable nonlinearity in the retraction behavior influenced by the external load as well as levels of PilT molecular motor protein. This includes reversal of motion near stall forces when the concentration of the PilT protein is lowered significantly. In order to explain this behavior, we analyze the coupling of TFP elasticity and interfacial behavior with PilT kinetics. We model retraction as reaction controlled and elongation as transport controlled process. The reaction rates vary with TFP deformation which is modeled as a compound elastic body consisting of multiple helical strands under axial load. Elongation is controlled by monomer transport which suffer entrapment due to excess PilT in the cell periplasm. Our analysis shows excellent agreement with a host of experimental observations and we present a possible biophysical relevance of model parameters through a mechano-chemical stall force map

  8. Assessment of HTGR Helium Compressor Analysis Tool Based on Newton-Raphson Numerical Application to Through-flow Analysis

    SciTech Connect (OSTI)

    Ji Hwan Kim; Hyeun Min Kim; Hee Cheon NO [Korea Advanced Institute of Science and Technology, 335 Gwahangno - 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2006-07-01T23:59:59.000Z

    This study describes the development of a computer program for analyzing the off-design performance of axial flow helium compressors, which is one of the major concerns for the power conversion system of a high temperature gas-cooled reactor (HTGR). The compressor performance has been predicted by the aerodynamic analysis of meridional flow with allowances for losses. The governing equations have been derived from Euler turbomachine equation and the streamline curvature method, and then they have been merged into linearized equations based on the Newton-Raphson numerical method. The effect of viscosity is considered by empirical correlations to introduce entropy rises caused by primary loss sources. Use of the method has been illustrated by applying it to a 20-stage helium compressor of the GTHTR300 plant. As a result, the flow throughout the stages of the compressor has been predicted and the compressor characteristics have been also investigated according to the design specification. The program results show much better stability and good convergence with respect to other through-flow methods, and good agreement with the compressor performance map provided by JAEA. (authors)

  9. Type Ia Supernova Explosion: Gravitationally Confined Detonation

    E-Print Network [OSTI]

    Tomasz Plewa; Alan Calder; Don Lamb

    2004-05-08T23:59:59.000Z

    We present a new mechanism for Type Ia supernova explosions in massive white dwarfs. The proposed scenario follows from relaxing the assumption of symmetry in the model and involves a detonation created in an unconfined environment. The explosion begins with an essentially central ignition of stellar material initiating a deflagration. This deflagration results in the formation of a buoyantly-driven bubble of hot material that reaches the stellar surface at supersonic speeds. The bubble breakout forms a strong pressure wave that laterally accelerates fuel-rich outer stellar layers. This material, confined by gravity to the white dwarf, races along the stellar surface and is focused at the location opposite to the point of the bubble breakout. These streams of nuclear fuel carry enough mass and energy to trigger a detonation just above the stellar surface. The flow conditions at that moment support a detonation that will incinerate the white dwarf and result in an energetic explosion. The stellar expansion following the deflagration redistributes stellar mass in a way that ensures production of intermediate mass and iron group elements consistent with observations. The ejecta will have a strongly layered structure with a mild amount of asymmetry following from the early deflagration phase. This asymmetry, combined with the amount of stellar expansion determined by details of the evolution (principally the energetics of deflagration, timing of detonation, and structure of the progenitor), can be expected to create a family of mildly diverse Type Ia supernova explosions.

  10. On the asymptotic homotopy type of inductive limit Type ...

    E-Print Network [OSTI]

    In this note we exhibit large classes of (projeetionless) stable, nuclear C*- algebras whose asymptotic homotopy type is determined by K-theoretical data.

  11. Flow Duration Curve Load Duration Curve

    E-Print Network [OSTI]

    Flow Duration Curve Load Duration Curve 1. Develop Flow Duration Curve 2. Estimate load given flow and concentration data--select appropriate conversion factors 3. Develop Load Duration Curve 4. Plot observed data with Load Duration Curve What are they? How do you make one? Describes the percent of time a flow rate

  12. Stochastic models for turbulent reacting flows

    SciTech Connect (OSTI)

    Kerstein, A. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01T23:59:59.000Z

    The goal of this program is to develop and apply stochastic models of various processes occurring within turbulent reacting flows in order to identify the fundamental mechanisms governing these flows, to support experimental studies of these flows, and to further the development of comprehensive turbulent reacting flow models.

  13. 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.

  14. Mirrored serpentine flow channels for fuel cell

    DOE Patents [OSTI]

    Rock, Jeffrey Allan (Rochester, NY)

    2000-08-08T23:59:59.000Z

    A PEM fuel cell having serpentine flow field channels wherein the input/inlet legs of each channel border the input/inlet legs of the next adjacent channels in the same flow field, and the output/exit legs of each channel border the output/exit legs of the next adjacent channels in the same flow field. The serpentine fuel flow channels may be longer, and may contain more medial legs, than the serpentine oxidant flow channels.

  15. Rheo-optical determination of flow birefringence and flow dichroism with the pulsed laser method

    E-Print Network [OSTI]

    Rheo-optical determination of flow birefringence and flow dichroism with the pulsed laser method online 29 August 2006 Rheo-optical measurements of the flow birefringence, flow dichroism systems under flow. However, the standard setup of an optical train, using phase modulation for the rheo-optical

  16. Connectivity due to preferential flow controls water flow and solute transport at the hillslope scale

    E-Print Network [OSTI]

    Weiler, Markus

    feedback, flow through the fractured bedrock, kinematic wave routing and flow through discrete preferentialConnectivity due to preferential flow controls water flow and solute transport at the hillslope the major controls on water flow and solute transport at the hillslope scale remains a major topic

  17. Type of Space Bulb Type #/House Fixture Style Greenhouse #

    E-Print Network [OSTI]

    Pawlowski, Wojtek

    Type of Space Bulb Type #/House Fixture Style Greenhouse # 1 Lu 430/Lu 400 24 White box style 2 Lu No bulbs 0 N/A Seed harvest room F32 T8/TL 841 90 bulbs VIGS Room F032 /741/ECO 60 bulbs Chamber Model Bulb

  18. Cumulant expansions for atmospheric flows

    E-Print Network [OSTI]

    Ait-Chaalal, Farid; Meyer, Bettina; Marston, J B

    2015-01-01T23:59:59.000Z

    The equations governing atmospheric flows are nonlinear, and consequently the hierarchy of cumulant equations is not closed. But because atmospheric flows are inhomogeneous and anisotropic, the nonlinearity may manifests itself only weakly through interactions of mean fields with disturbances such as thermals or eddies. In such situations, truncations of the hierarchy of cumulant equations hold promise as a closure strategy. We review how truncations at second order can be used to model and elucidate the dynamics of turbulent atmospheric flows. Two examples are considered. First, we study the growth of a dry convective boundary layer, which is heated from below, leading to turbulent upward energy transport and growth of the boundary layer. We demonstrate that a quasilinear truncation of the equations of motion, in which interactions of disturbances among each other are neglected but interactions with mean fields are taken into account, can successfully capture the growth of the convective boundary layer. Seco...

  19. Monitoring probe for groundwater flow

    DOE Patents [OSTI]

    Looney, B.B.; Ballard, S.

    1994-08-23T23:59:59.000Z

    A monitoring probe for detecting groundwater migration is disclosed. The monitor features a cylinder made of a permeable membrane carrying an array of electrical conductivity sensors on its outer surface. The cylinder is filled with a fluid that has a conductivity different than the groundwater. The probe is placed in the ground at an area of interest to be monitored. The fluid, typically saltwater, diffuses through the permeable membrane into the groundwater. The flow of groundwater passing around the permeable membrane walls of the cylinder carries the conductive fluid in the same general direction and distorts the conductivity field measured by the sensors. The degree of distortion from top to bottom and around the probe is precisely related to the vertical and horizontal flow rates, respectively. The electrical conductivities measured by the sensors about the outer surface of the probe are analyzed to determine the rate and direction of the groundwater flow. 4 figs.

  20. Monitoring probe for groundwater flow

    DOE Patents [OSTI]

    Looney, Brian B. (Aiken, SC); Ballard, Sanford (Albuquerque, NM)

    1994-01-01T23:59:59.000Z

    A monitoring probe for detecting groundwater migration. The monitor features a cylinder made of a permeable membrane carrying an array of electrical conductivity sensors on its outer surface. The cylinder is filled with a fluid that has a conductivity different than the groundwater. The probe is placed in the ground at an area of interest to be monitored. The fluid, typically saltwater, diffuses through the permeable membrane into the groundwater. The flow of groundwater passing around the permeable membrane walls of the cylinder carries the conductive fluid in the same general direction and distorts the conductivity field measured by the sensors. The degree of distortion from top to bottom and around the probe is precisely related to the vertical and horizontal flow rates, respectively. The electrical conductivities measured by the sensors about the outer surface of the probe are analyzed to determine the rate and direction of the groundwater flow.

  1. Measurements of Gas Bubble Size Distributions in Flowing Liquid Mercury

    SciTech Connect (OSTI)

    Wendel, Mark W [ORNL; Riemer, Bernie [ORNL; Abdou, Ashraf A [ORNL

    2012-01-01T23:59:59.000Z

    ABSTRACT Pressure waves created in liquid mercury pulsed spallation targets have been shown to induce cavitation damage on the target container. One way to mitigate such damage would be to absorb the pressure pulse energy into a dispersed population of small bubbles, however, measuring such a population in mercury is difficult since it is opaque and the mercury is involved in a turbulent flow. Ultrasonic measurements have been attempted on these types of flows, but the flow noise can interfere with the measurement, and the results are unverifiable and often unrealistic. Recently, a flow loop was built and operated at Oak Ridge National Labarotory to assess the capability of various bubbler designs to deliver an adequate population of bubbles to mitigate cavitation damage. The invented diagnostic technique involves flowing the mercury with entrained gas bubbles in a steady state through a horizontal piping section with a glass-window observation port located on the top. The mercury flow is then suddenly stopped and the bubbles are allowed to settle on the glass due to buoyancy. Using a bright-field illumination and a high-speed camera, the arriving bubbles are detected and counted, and then the images can be processed to determine the bubble populations. After using this technique to collect data on each bubbler, bubble size distributions were built for the purpose of quantifying bubbler performance, allowing the selection of the best bubbler options. This paper presents the novel procedure, photographic technique, sample visual results and some example bubble size distributions. The best bubbler options were subsequently used in proton beam irradiation tests performed at the Los Alamos National Laboratory. The cavitation damage results from the irradiated test plates in contact with the mercury are available for correlation with the bubble populations. The most effective mitigating population can now be designed into prototypical geometries for implementation into an actual SNS target.

  2. High gas flow alpha detector

    DOE Patents [OSTI]

    Bolton, R.D.; Bounds, J.A.; Rawool-Sullivan, M.W.

    1996-05-07T23:59:59.000Z

    An alpha detector for application in areas of high velocity gas flows, such as smokestacks and air vents. A plurality of spaced apart signal collectors are placed inside an enclosure, which would include smokestacks and air vents, in sufficient numbers to substantially span said enclosure so that gas ions generated within the gas flow are electrostatically captured by the signal collector means. Electrometer means and a voltage source are connected to the signal collectors to generate an electrical field between adjacent signal collectors, and to indicate a current produced through collection of the gas ions by the signal collectors. 4 figs.

  3. High gas flow alpha detector

    DOE Patents [OSTI]

    Bolton, Richard D. (Los Alamos, NM); Bounds, John A. (Los Alamos, NM); Rawool-Sullivan, Mohini W. (Los Alamos, NM)

    1996-01-01T23:59:59.000Z

    An alpha detector for application in areas of high velocity gas flows, such as smokestacks and air vents. A plurality of spaced apart signal collectors are placed inside an enclosure, which would include smokestacks and air vents, in sufficient numbers to substantially span said enclosure so that gas ions generated within the gas flow are electrostatically captured by the signal collector means. Electrometer means and a voltage source are connected to the signal collectors to generate an electrical field between adjacent signal collectors, and to indicate a current produced through collection of the gas ions by the signal collectors.

  4. Nuclear reactor downcomer flow deflector

    DOE Patents [OSTI]

    Gilmore, Charles B. (Greensburg, PA); Altman, David A. (Pittsburgh, PA); Singleton, Norman R. (Murrysville, PA)

    2011-02-15T23:59:59.000Z

    A nuclear reactor having a coolant flow deflector secured to a reactor core barrel in line with a coolant inlet nozzle. The flow deflector redirects incoming coolant down an annulus between the core barrel and the reactor vessel. The deflector has a main body with a front side facing the fluid inlet nozzle and a rear side facing the core barrel. The rear side of the main body has at least one protrusion secured to the core barrel so that a gap exists between the rear side of the main body adjacent the protrusion and the core barrel. Preferably, the protrusion is a relief that circumscribes the rear side of the main body.

  5. Interfacial flows in corrugated microchannels: flow regimes, transitions and hysteresis

    E-Print Network [OSTI]

    Feng, James J.

    , 1266-1276 (2011), doi:10.1016/j.ijmultiphaseflow.2011.08.003 #12;model, microfluidics, porous media 1 of displacing oil by water in enhanced oil recovery (Marle, 1981; Lenormand et al., 1988). More recently on hy- drodynamic principles and concrete flow mechanisms. In fact, conflicting assumptions have been

  6. axisymmetric thermal flows: Topics by E-print Network

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

    where the inclination of field lines to the axis is too small to drive a centrifugal wind, we inject a thin, axial jet, expected to form electromagnetically near black holes....

  7. JOURNAL OF ELECTRON MICROSCOPY TECHNIQUE 16:160-166 11990) A Stopped-Flow/Rapid-Freezing Machine With Millisecond

    E-Print Network [OSTI]

    in chemical kinetics (Johnson, 1986)with a propane jet freezing unit previously used to prepare static samples a Berger-type mixer and into a thin-walled copper flow cell (Fig. 1). After a predetermined delay, Rockford, IL) con- nected to a 1.5-mm Mark I Berger-type mixer (Re- search Instruments and Manufacturi

  8. The conformation change of model polymers in stochastic flow fields: Flow through fixed beds

    E-Print Network [OSTI]

    Shaqfeh, Eric

    The conformation change of model polymers in stochastic flow fields: Flow through fixed beds Alisa that as a polymer solution flows through a fixed bed, the pressure drop neces- sary to pump the solution may

  9. New approaches for modeling type Ia supernovae

    E-Print Network [OSTI]

    Zingale, Michael; Almgren, Ann S.; Bell, John B.; Day, Marcus S.; Rendleman, Charles A.; Woosley, Stan

    2007-01-01T23:59:59.000Z

    runaway in Type Ia supernovae: How to run away? oIgnition in Type Ia Supernovae. II. A Three- dimensionalnumber modeling of type Ia supernovae. I. hydrodynamics.

  10. Quantitative imaging of turbulent and reacting flows

    SciTech Connect (OSTI)

    Paul, P.H. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01T23:59:59.000Z

    Quantitative digital imaging, using planar laser light scattering techniques is being developed for the analysis of turbulent and reacting flows. Quantitative image data, implying both a direct relation to flowfield variables as well as sufficient signal and spatial dynamic range, can be readily processed to yield two-dimensional distributions of flowfield scalars and in turn two-dimensional images of gradients and turbulence scales. Much of the development of imaging techniques to date has concentrated on understanding the requisite molecular spectroscopy and collision dynamics to be able to determine how flowfield variable information is encoded into the measured signal. From this standpoint the image is seen as a collection of single point measurements. The present effort aims at realizing necessary improvements in signal and spatial dynamic range, signal-to-noise ratio and spatial resolution in the imaging system as well as developing excitation/detection strategies which provide for a quantitative measure of particular flowfield scalars. The standard camera used for the study is an intensified CCD array operated in a conventional video format. The design of the system was based on detailed modeling of signal and image transfer properties of fast UV imaging lenses, image intensifiers and CCD detector arrays. While this system is suitable for direct scalar imaging, derived quantities (e.g. temperature or velocity images) require an exceptionally wide dynamic range imaging detector. To apply these diagnostics to reacting flows also requires a very fast shuttered camera. The authors have developed and successfully tested a new type of gated low-light level detector. This system relies on fast switching of proximity focused image-diode which is direct fiber-optic coupled to a cooled CCD array. Tests on this new detector show significant improvements in detection limit, dynamic range and spatial resolution as compared to microchannel plate intensified arrays.

  11. Superconducting flux flow digital circuits

    DOE Patents [OSTI]

    Hietala, V.M.; Martens, J.S.; Zipperian, T.E.

    1995-02-14T23:59:59.000Z

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs) are disclosed. Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics. 8 figs.

  12. Neutrino Factory Mercury Flow Loop

    E-Print Network [OSTI]

    McDonald, Kirk

    ­ Could require double containment of mercury ­ Chase will certainly have a drain back into hot cell Decay 2010 #12;Hg Flow Overflow · Minimize pressure drops through piping Overflow Mercury Drain drops Gravity Drain Beam Dumptransitioning to 1 cm nozzle · Actual NF Hg inventory may reach SNS Gravity Drain

  13. Message Flow Modeling Oscar Nierstrasz

    E-Print Network [OSTI]

    Nierstrasz, Oscar

    Message Flow Modeling Oscar Nierstrasz and Dennis Tsichritzis Computer Systems Research Group University of Toronto ABSTRACT A message management system provides users with a facility for automatically handling messages. This paper describes a technique for characterizing the behaviour of such a system

  14. Collective flow in small systems

    E-Print Network [OSTI]

    Piotr Bozek; Wojciech Broniowski

    2014-07-24T23:59:59.000Z

    The large density of matter in the interaction region of the proton-nucleus or deuteron-nucleus collisions enables the collective expansion of the fireball. Predictions of the hydrodynamic model for the asymmetric transverse flow are presented and compared to experimental data.

  15. Stopping Cooling Flows with Jets

    E-Print Network [OSTI]

    Fabrizio Brighenti; William G. Mathews

    2006-01-24T23:59:59.000Z

    We describe 2D gasdynamical models of jets that carry mass as well as energy to the hot gas in galaxy clusters. These flows have many attractive attributes for solving the galaxy cluster cooling flow problem: Why the hot gas temperature and density profiles resemble cooling flows but show no spectral evidence of cooling to low temperatures. Using an approximate model for the cluster A1795, we show that mass-carrying jets can reduce the overall cooling rate to or below the low values implied by X-ray spectra. Biconical subrelativistic jets, described with several ad hoc parameters, are assumed to be activated when gas flows toward or cools near a central supermassive black hole. As the jets proceed out from the center they entrain more and more ambient gas. The jets lose internal pressure by expansion and are compressed by the ambient cluster gas, becoming rather difficult to observe. For a wide variety of initial jet parameters and several feedback scenarios the global cooling can be suppressed for many Gyrs while maintaining cluster temperature profiles similar to those observed. The intermittancy of the feedback generates multiple generations of X-ray cavities similar to those observed in the Perseus Cluster and elsewhere.

  16. Flow preconditioner for electrostatic precipitator

    SciTech Connect (OSTI)

    Honacker, H.; Drlik, R.J.

    1980-01-01T23:59:59.000Z

    A flow preconditioner for an electrostatic precipitator removes particulate matter from a stream of polluted gas immediately after it passes through a tangential inlet at the lower end of a vertical cylindrical housing and straightens and divides the stream into laminations parallel to the axis of the housing. It comprises an annular ledge or choke ring extending inwardly from said housing above the inlet and an assembly of vanes above said ledge extending radially from the axis of the housing and angularly spaced apart. Each of said vanes has a flow receiving edge directed toward said inlet, a curved portion extending upwardly and away from said inlet, and a flat portion extending upwardly from said curved portion in a plane parallel to the housing axis. The curved portion of each vane defines a trough having a camber which gradually decreases along its span from the outer end of the vane towards the axis of the housng, together with means to vary the centrifugal flow distribution relative to the housing to render the preconditioner adjustable for various flow capacities.

  17. Documenting Organizational Process Flow Modeling

    E-Print Network [OSTI]

    Schweik, Charles M.

    1 Documenting Organizational Processes or Process Flow Modeling Analysis Phase ­ Three Steps that describes (1) the current, and (2) the future structure of an organizational process ·"Natural language ­ An overview of an organizational system showing · system boundaries, · external entities that interact

  18. Flow assurance and multiphase pumping 

    E-Print Network [OSTI]

    Nikhar, Hemant G.

    2009-05-15T23:59:59.000Z

    -in-Pipe?????????????????????????????????????. 42 Non-Jacketed Insulation Systems?????????????????????????? 42 Syntactic Insulation?????????????????????????????????. 42 Heating?????????????????????????????????????????? 43 Pipeline Configurations for Heating????????????????????????? 45 Subsea... Various Chemicals Used in Oil and Gas Production Operations????????. 38 15 Seawater Temperature Gradients???????????????????????.. 43 16 Flow Model Schematic?????????????????????????????.. 44 17 Deliverability Affected by Cooling Effect of Pipeline...

  19. Comments on "Microscale flow visualization"

    E-Print Network [OSTI]

    A. Kwang-Hua Chu

    2005-10-22T23:59:59.000Z

    We make comments on the presentation of Sinton's paper (Microfluidics and Nanofluidics {\\bf 1}: 2, 2004) about the microscale flow visualization since the effects of the roughness along the microfabricated wall upon the current macroflow visualization methods could be significant and cannot be neglected in microdomain and even nanodomain.

  20. Rinse trough with improved flow

    DOE Patents [OSTI]

    O`Hern, T.J.; Grasser, T.W.

    1998-08-11T23:59:59.000Z

    Novel rinse troughs accomplish thorough uniform rinsing. The troughs are suitable for one or more essentially planar objects having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs provide uniform rinse fluid flow over the objects` surfaces to accomplish a more thorough rinse than prior art troughs. 5 figs.