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1

MHK Technologies/Pneumatically Stabilized Platform PSP | Open Energy  

Open Energy Info (EERE)

MHK Technologies/Pneumatically Stabilized Platform PSP MHK Technologies/Pneumatically Stabilized Platform PSP < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Pneumatically Stabilized Platform PSP.jpg Technology Profile Primary Organization Float Inc Technology Resource Click here Wave Technology Type Click here Attenuator Technology Readiness Level Click here TRL 5 6 System Integration and Technology Laboratory Demonstration Technology Description The PSP is a distinct type of pneumatic platform one in which the platform is composed of a number of cylindrical shaped components packed together in a rectangular pattern to form a module Each cylinder is sealed at the top open to the ocean at its base and contains air at a pressure slightly above atmospheric pressure Modules can be of a size that are relatively easy to manipulate as shown in the simplified drawing below

2

Stabilization of vortex solitons in nonlocal nonlinear media  

SciTech Connect

We study the evolution of vortex solitons in optical media with a nonlocal nonlinear response. We employ a modulation theory for the vortex parameters based on an averaged Lagrangian, and analyze the azimuthal evolution of both the vortex width and diffractive radiation. We describe analytically the physical mechanism for vortex stabilization due to the long-range nonlocal nonlinear response, the effect observed earlier in numerical simulations only.

Minzoni, Antonmaria A. [Fenomenos Nonlineales y Mecanica (FENOMEC), Department of Mathematics and Mechanics, Instituto de Investigacion en Matematicas Aplicadas y Sistemas, Universidad Nacional Autonoma de Mexico, 01000 Mexico D.F. (Mexico); Smyth, Noel F. [School of Mathematics and Maxwell Institute for Mathematical Sciences, University of Edinburgh, Edinburgh EH9 3JZ, Scotland (United Kingdom); Worthy, Annette L. [School of Mathematics and Applied Statistics, University of Wollongong, Wollongong NSW 2522 (Australia); Kivshar, Yuri S. [Nonlinear Physics Center, Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200 (Australia)

2007-12-15T23:59:59.000Z

3

Stability of an optical vortex in a circular nematic cell  

SciTech Connect

The stability of an optical vortex in a cell with a circular cross section containing a nematic liquid crystal is studied. A modulation theory based on an averaged Lagrangian formulation is developed to study this stability. It is found that the vortex is stable unless the radius of the cell is very small, nearly the width of the vortex itself. Based on the analysis of a stationary vortex, the stability of a low-amplitude vortex in a large cell under the influence of its orbital angular momentum and the repelling effect of the cell boundary are studied. The predictions of this modulation theory are found to be in excellent agreement with numerical simulations.

Minzoni, Antonmaria A. [Fenomenos Nonlineales y Mecanica (FENOMEC), Departamento de Matematicas y Mecanica, Instituto de Investigacion en Matematicas Aplicadas y Sistemas, Universidad Nacional Autonoma de Mexico, 01000 Mexico D.F. (Mexico); Smyth, Noel F. [School of Mathematics and Maxwell Institute for Mathematical Sciences, University of Edinburgh, Edinburgh EH9 3JZ, Scotland (United Kingdom); Xu Zhiyong [Nonlinear Physics Center, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

2010-03-15T23:59:59.000Z

4

Stabilization and equilibrium control of a new pneumatic cart-seesaw system  

Science Conference Proceedings (OSTI)

This investigation describes the mechanical configuration and control environment for a novel cart-seesaw system. This mechanism is called a super articulated mechanical system (SAMS). The system comprises a cart that slides on the pneumatic rodless ... Keywords: Ball-and-beam, Cart-seesaw system, Robots

J. Lin; J. h. Zhan; Julian Chang

2008-03-01T23:59:59.000Z

5

Stability of a Two-Layer Quasigeostrophic Vortex over Axisymmetric Localized Topography  

Science Conference Proceedings (OSTI)

The stability of a quasigeostrophic vortex over a radially symmetric topographic feature (elevation or depression) in a two-layer ocean on the f plane is examined. This article’s concern is with compensated vortices, that is, those in which the ...

E. S. Benilov

2005-01-01T23:59:59.000Z

6

Generation and Stability of a Quasi-Permanent Vortex in the Lofoten Basin  

Science Conference Proceedings (OSTI)

In the Nordic seas the Lofoten Basin is a region of high mesoscale activity. The generation mechanism and the conditions for the stability of a quasi-permanent vortex in the center of the Lofoten Basin are studied with a high-resolution ocean ...

Armin Köhl

2007-11-01T23:59:59.000Z

7

Rotary pneumatic valve  

DOE Patents (OSTI)

A rotary pneumatic valve which is thrust balanced and the pneumatic pressure developed produces only radial loads on the valve cylinder producing negligible resistance and thus minimal torque on the bearings of the valve. The valve is multiplexed such that at least two complete switching cycles occur for each revolution of the cylinder spindle. 4 figs.

Hardee, H.C.

1989-08-02T23:59:59.000Z

8

Pneumatic Conveyance Device  

The Pneumatic Conveyance Device is capable of dislodging, capturing, and conveying solid material, wet or dry, from a depth of 70+ feet, while discharging through a 100+ foot conveyance hose.  The device was developed to remove water and solid ...

9

Pneumatic battery : a chemical alternative to pneumatic energy storage  

E-Print Network (OSTI)

Pneumatic power is traditionally provided by compressed air contained in a pressurized vessel. This method of energy storage is analogous to an electrical capacitor. This study sought to create an alternative pneumatic ...

Kojimoto, Nigel (Nigel C.)

2012-01-01T23:59:59.000Z

10

Pneumatic soil removal tool  

DOE Patents (OSTI)

A soil removal tool is provided for removing radioactive soil, rock and other debris from the bottom of an excavation, while permitting the operator to be located outside of a containment for that excavation. The tool includes a fixed jaw, secured to one end of an elongate pipe, which cooperates with a movable jaw pivotably mounted on the pipe. Movement of the movable jaw is controlled by a pneumatic cylinder mounted on the pipe. The actuator rod of the pneumatic cylinder is connected to a collar which is slidably mounted on the pipe and forms part of the pivotable mounting assembly for the movable jaw. Air is supplied to the pneumatic cylinder through a handle connected to the pipe, under the control of an actuator valve mounted on the handle, to provide movement of the movable jaw.

Neuhaus, John E. (Newport News, VA)

1992-01-01T23:59:59.000Z

11

Pneumatic soil removal tool  

Science Conference Proceedings (OSTI)

A soil tool is provided for removing radioactive soil, rock and debris from the bottom of an excavation, while permitting the operator to be located outside of a containment for that excavation. The tool includes a fixed jaw, secured to one end of an elongate pipe, which cooperates with a movable jaw pivotably mounted on the pipe. Movement of the movable jaw is controlled by a pneumatic cylinder on the pipe. The actuator rod of the pneumatic cylinder is connected to a collar which is slidably on the pipe and forms part of the pivotable mounting assembly for the movable jaw. Air is supplied to the pneumatic cylinder through a handle connected to the pipe, under the control of an actuator value mounted on the handle, to provide movement of the movable jaw.

Neuhaus, J.F.

1991-01-23T23:59:59.000Z

12

Pneumatic soil removal tool  

Science Conference Proceedings (OSTI)

A soil removal tool is provided for removing radioactive soil, rock and other debris from the bottom of an excavation, while permitting the operator to be located outside of a containment for that excavation. The tool includes a fixed jaw, secured to one end of an elongate pipe, which cooperates with a movable jaw pivotably mounted on the pipe. Movement of the movable jaw is controlled by a pneumatic cylinder mounted on the pipe. The actuator rod of the pneumatic cylinder is connected to a collar which is slidably mounted on the pipe and forms part of the pivotable mounting assembly for the movable jaw. Air is supplied to the pneumatic cylinder through a handle connected to the pipe, under the control of an actuator valve mounted on the handle, to provide movement of the movable jaw. 3 figs.

Neuhaus, J.E.

1992-10-13T23:59:59.000Z

13

Pneumatic clutch apparatus  

SciTech Connect

A pneumatic clutch apparatus is described comprising: a pneumatic clutch disposed at the rear of a transmission and including a pneumatic actuator for engaging and disengaging the clutch, a rotary passage adapted to rotate together with the clutch and connected to the actuator; a stationary passage stationary with respect to the clutch and connected to a pneumatic pressure control mechanism disposed outside the clutch; and a rotary joint including a connecting passage for connecting the rotary passage and the stationary passage together; the rotary joint having a rotary portion to which the rotary passage is fixed and a stationary portion to which the stationary passage is fixed, and the stationary portion being fixed to a housing of the transmission and rotatably supporting the rotary portion. A cylindrical intermediate member is disposed between the rotary portion and the stationary portion of the rotary joint. Air passages in the stationary portion and the rotary portion are connected together through an air passage in the intermediate member. The intermediate member is rotatably fitted to the rotary portion and the stationary portion through seals which seal the air passage. A connecting mechanism is operable to connect the intermediate member to the rotary portion when the intermediate member and the rotary portion occupy a predetermined relative angular position.

Kamio, T.

1987-03-03T23:59:59.000Z

14

Continued Development and Improvement of Pneumatic Heavy Vehicles  

SciTech Connect

The objective of this applied research effort led by Georgia Tech Research Institute is the application of pneumatic aerodynamic technology previously developed and patented by us to the design of an appropriate Heavy Vehicle (HV) tractor-trailer configuration, and experimental confirmation of this pneumatic configuration's improved aerodynamic characteristics. In Phases I to IV of our previous DOE program (Reference 1), GTRI has developed, patented, wind-tunnel tested and road-tested blown aerodynamic devices for Pneumatic Heavy Vehicles (PHVs) and Pneumatic Sports Utility Vehicles (PSUVs). To further advance these pneumatic technologies towards HV and SUV applications, additional Phase V tasks were included in the first year of a continuing DOE program (Reference 2). Based on the results of the Phase IV full-scale test programs, these Phase V tasks extended the application of pneumatic aerodynamics to include: further economy and performance improvements; increased aerodynamic stability and control; and safety of operation of Pneumatic HVs. Continued development of a Pneumatic SUV was also conducted during the Phase V program. Phase V was completed in July, 2003; its positive results towards development and confirmation of this pneumatic technology are reported in References 3 and 4. The current Phase VI of this program was incrementally funded by DOE in order to continue this technology development towards a second fuel economy test on the Pneumatic Heavy Vehicle. The objectives of this current Phase VI research and development effort (Ref. 5) fall into two categories: (1) develop improved pneumatic aerodynamic technology and configurations on smaller-scale models of the advanced Pneumatic Heavy Vehicle (PHV); and based on these findings, (2) redesign, modify, and re-test the modified full-scale PHV test vehicle. This second objective includes conduct of an on-road preliminary road test of this configuration to prepare it for a second series of SAE Type-U fuel economy evaluations, as described in Ref. 5. Both objectives are based on the pneumatic technology already developed and confirmed for DOE OHVT/OAAT in Phases I-V. This new Phase VI effort was initiated by contract amendment to the Phase V effort using carryover FY02 funds. This were conducted under a new and distinct project number, GTRI Project A-6935, separate from the Phase I-IV program. However, the two programs are closely integrated, and thus Phase VI continues with the previous program and goals.

Robert J. Englar

2005-07-15T23:59:59.000Z

15

Pneumatic energy storage  

DOE Green Energy (OSTI)

An essential component to hybrid electric and electric vehicles is energy storage. A power assist device could also be important to many vehicle applications. This discussion focuses on the use of compressed gas as a system for energy storage and power in vehicle systems. Three possible vehicular applications for which these system could be used are discussed in this paper. These applications are pneumatically driven vehicles, series hybrid electric vehicles, and power boost for electric and conventional vehicles. One option for a compressed gas system is as a long duration power output device for purely pneumatic and hybrid cars. This system must provide enough power and energy to drive under normal conditions for a specified time or distance. The energy storage system for this use has the requirement that it will be highly efficient, compact, and have low mass. Use of a compressed gas energy storage as a short duration, high power output system for conventional motor vehicles could reduce engine size or reduce transient emissions. For electric vehicles this kind of system could lengthen battery life by providing battery load leveling during accelerations. The system requirements for this application are that it be compact and have low mass. The efficiency of the system is a secondary consideration in this application.

Flowers, D.

1995-09-19T23:59:59.000Z

16

Vortex methods and vortex statistics  

SciTech Connect

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

Chorin, A.J.

1993-05-01T23:59:59.000Z

17

Fuzzy logic hardware implementation for pneumatic control of one DOF pneumatic robot  

Science Conference Proceedings (OSTI)

The pneumatic actuators can be a useful way to control the position of a manipulator robot, instead of an electrical actuator. The major problem with pneumatic actuators is the compressibility of the air, due to the fact that the mathematical model is ... Keywords: FPGA, fuzzy logic, hardware, pneumatic, robot

Juan-Manuel Ramos-Arreguin; Emmanuel Guillen-Garcia; Sandra Canchola-Magdaleno; Jesus-Carlos Pedraza-Ortega; Efren Gorrostieta-Hurtado; Marco-Antonio Aceves-Fernández; Carlos-Alberto Ramos-Arreguin

2010-11-01T23:59:59.000Z

18

Pneumatic conveying of pulverized solvent refined coal  

DOE Patents (OSTI)

A method for pneumatically conveying solvent refined coal to a burner under conditions of dilute phase pneumatic flow so as to prevent saltation of the solvent refined coal in the transport line by maintaining the transport fluid velocity above approximately 95 ft/sec.

Lennon, Dennis R. (Allentown, PA)

1984-11-06T23:59:59.000Z

19

RANGE INCREASER FOR PNEUMATIC GAUGES  

DOE Patents (OSTI)

An improved pneumatic gage is offered in which the linear range has been increased without excessive air consumption. This has been accomplished by providing an expansible antechamber connected to the nozzle of the gage so that the position of the nozzle with respect to the workpiece is varied automatically by variation in pressure within the antechamber. This arrangement ensures that the nozzle-to-workpiece clearance is maintained within certain limits, thus obtaining a linear relation of air flow to nozzle-to-workpiece clearance over a wider range.

Fowler, A.H.; Seaborn, G.B. Jr.

1960-09-27T23:59:59.000Z

20

Dynamic programming for hybrid pneumatic vehicles  

Science Conference Proceedings (OSTI)

Pneumatic hybridization of internal combustion engines may prove to be a viable and cost-efficient alternative to electric hybridization. This paper investigates the fuel consumption reduction that is possible with this rather new concept in combination ...

Christian Dönitz; Iulian Vasile; Christopher Onder; Lino Guzzella

2009-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Vortex Energy | Open Energy Information  

Open Energy Info (EERE)

by expanding it. Vortex Energy is a company located in Germany . References "Vortex Energy" Retrieved from "http:en.openei.orgwindex.php?titleVortexEnergy&oldid352892...

22

Instrument calibration using the pneumatic deadweight tester  

SciTech Connect

One of the most difficult problems facing the instrument engineer is the accurate calibration of orifice meters, particularly at remote or inaccessible locations. The object of this paper is to describe a unique solution to this problem, an automatic pneumatic deadweight tester utilizing the floating ball principle. The Ametek Model PK Pneumatic Deadweight Tester is an ideal instrument to use for the calibration of orifice meters. This instrument provides unexcelled accuracy combined with reliable operation and ease of use for both field and laboratory calibration. It has been accepted by most of the gas transmission companies as a pressure standard for meter calibration.

Johnson, E.R.

1984-04-01T23:59:59.000Z

23

Guidelines help design pneumatic control systems  

Science Conference Proceedings (OSTI)

The three areas of particular interest to the gas-transmission engineer about pneumatic-instrument-operated control valves are (1) the fail-position probability of a system, (2) the designated action required for each component in the pneumatic circuit, and (3) the schematically defined position of each component. Compared with self-operated control valves, the instrument-operated systems perform many more functions; they can control the flow and the volume or flow-volume combinations, with both pressure override and underride, and will adapt conveniently to remote operation. Schematic diagrams illustrate the numerous system designs possible for pressure-regulation, flow-control, and relief-valve duties.

Curry, R.N.

1981-01-26T23:59:59.000Z

24

Enhancing in situ bioremediation with pneumatic fracturing  

Science Conference Proceedings (OSTI)

A major technical obstacle affecting the application of in situ bioremediation is the effective distribution of nutrients to the subsurface media. Pneumatic fracturing can increase the permeability of subsurface formations through the injection of high pressure air to create horizontal fracture planes, thus enhancing macro-scale mass-transfer processes. Pneumatic fracturing technology was demonstrated at two field sites at Tinker Air Force Base, Oklahoma City, Oklahoma. Tests were performed to increase the permeability for more effective bioventing, and evaluated the potential to increase permeability and recovery of free product in low permeability soils consisting of fine grain silts, clays, and sedimentary rock. Pneumatic fracturing significantly improved formation permeability by enhancing secondary permeability and by promoting removal of excess soil moisture from the unsaturated zone. Postfracture airflows were 500% to 1,700% higher than prefracture airflows for specific fractured intervals in the formation. This corresponds to an average prefracturing permeability of 0.017 Darcy, increasing to an average of 0.32 Darcy after fracturing. Pneumatic fracturing also increased free-product recovery rates of number 2 fuel from an average of 587 L (155 gal) per month before fracturing to 1,647 L (435 gal) per month after fracturing.

Anderson, D.B.; Peyton, B.M.; Liskowitz, J.L.; Fitzgerald, C.; Schuring, J.R.

1994-04-01T23:59:59.000Z

25

Pneumatic Transport of Pulverized Wood Pellets  

Science Conference Proceedings (OSTI)

The use of biomass fuels poses new issues for utilities seeking to employ these resources to augment their contributions to renewable energy. The direct combustion of biomass in a conventional utility boiler will almost always involve pneumatic transport and injection as is currently done with pulverized coal. However, differences in physical properties between biomass fuels and coal are evident. For instance, the large particle size range of a typical biomass fuel (13 mm) is far greater than that of pul...

2010-09-30T23:59:59.000Z

26

Twisted vortex state  

E-Print Network (OSTI)

We study a twisted vortex bundle where quantized vortices form helices circling around the axis of the bundle in a "force-free" configuration. Such a state is created by injecting vortices into rotating vortex-free superfluid. Using continuum theory we determine the structure and the relaxation of the twisted state. This is confirmed by numerical calculations. We also present experimental evidence of the twisted vortex state in superfluid 3He-B.

V. B. Eltsov; A. P. Finne; R. Hanninen; J. Kopu; M. Krusius; M. Tsubota; E. V. Thuneberg

2006-02-28T23:59:59.000Z

27

Lifetime Prediction of Pneumatic Conveyor Bends with the Aid of ...  

Science Conference Proceedings (OSTI)

Feb 1, 2002 ... Pneumatic conveying pipelines are used throughout a variety of industries, from food processing/packing to power generation plants, as an ...

28

Improved vortex reactor system  

DOE Patents (OSTI)

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

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

1995-01-01T23:59:59.000Z

29

Installation Performance Report on Pneumatic Conveying Consolidation.  

Science Conference Proceedings (OSTI)

The management at Lane Plywood saw an opportunity to reduce energy consumption at the mill by combining two pneumatic conveying systems into a single system. The combined connected load on the original two systems was 175 HP. The connected load on the remaining system is a single 75 HP drive. After calculating the demand on the former system and projecting the demand on the present system, a savings of 198,549 kWh/year was projected. Lane Plywood pays on average of $O.01347/kWh for electrical energy. The value of the annual savings was $2,674. The cost estimate for the project was $22,100. On a simple payback basis the project was not attractive enough when compared to other capital opportunities. However, with the incentives offered by the Bonneville Power Administration, Sponsor Design Program, the project became attractive and was accomplished. From data collected in an extensive metering effort, energy savings are amounting to 254,274 kWh/year. This is over 56,000 kWh/year more than was projected. The reason for the favorable variance is a result of the method used by pneumatic conveying suppliers in forecasting drive blower drive loads. The mill management regards the project as having accomplished its objective and considers it a success.

Lane Plywood Corp.

1987-09-01T23:59:59.000Z

30

Development of Pneumatic Aerodynamic Devices to Improve the Performance, Economics, and Safety of Heavy Vehicles  

SciTech Connect

Under contract to the DOE Office of Heavy Vehicle Technologies, the Georgia Tech Research Institute (GTRI) is developing and evaluating pneumatic (blown) aerodynamic devices to improve the performance, economics, stability and safety of operation of Heavy Vehicles. The objective of this program is to apply the pneumatic aerodynamic aircraft technology previously developed and flight-tested by GTRI personnel to the design of an efficient blown tractor-trailer configuration. Recent experimental results obtained by GTRI using blowing have shown drag reductions of 35% on a streamlined automobile wind-tunnel model. Also measured were lift or down-load increases of 100-150% and the ability to control aerodynamic moments about all 3 axes without any moving control surfaces. Similar drag reductions yielded by blowing on bluff afterbody trailers in current US trucking fleet operations are anticipated to reduce yearly fuel consumption by more than 1.2 billion gallons, while even further reduction is possible using pneumatic lift to reduce tire rolling resistance. Conversely, increased drag and down force generated instantaneously by blowing can greatly increase braking characteristics and control in wet/icy weather due to effective ''weight'' increases on the tires. Safety is also enhanced by controlling side loads and moments caused on these Heavy Vehicles by winds, gusts and other vehicles passing. This may also help to eliminate the jack-knifing problem if caused by extreme wind side loads on the trailer. Lastly, reduction of the turbulent wake behind the trailer can reduce splash and spray patterns and rough air being experienced by following vehicles. To be presented by GTRI in this paper will be results developed during the early portion of this effort, including a preliminary systems study, CFD prediction of the blown flowfields, and design of the baseline conventional tractor-trailer model and the pneumatic wind-tunnel model.

Robert J. Englar

2000-06-19T23:59:59.000Z

31

VORTEX.PDF  

NLE Websites -- All DOE Office Websites (Extended Search)

vortex generator. Figure 5. The fan in its plenum-a two-speed stove fan mounted in a plywood box. It provides a vacuum at the top of the generator. The ruler is six inches long....

32

Improved vortex reactor system  

DOE Patents (OSTI)

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

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

1995-05-09T23:59:59.000Z

33

Research on Vortex Unstablity Caused by Bending Deformation of Drilling Bar in BTA Deep Hole Machining  

Science Conference Proceedings (OSTI)

Vortex and unstability of bending boring bar caused by cutting fluid force are researched, with Timoshenko beam model and mated vibration model, based on which machining quality of BTA deep hole drilling and tools life can be promoted in practice. Linear ... Keywords: deep hole boring, boring bar, Timoshenko beam, mating vibration, vortex motion stability

Zhanqi Hu; Wu Zhao

2009-04-01T23:59:59.000Z

34

Pneumatic solids feeder for coal gasification reactor  

DOE Patents (OSTI)

This invention is comprised of a pneumatic feeder system for a coal gasification reactor which includes one or more feeder tubes entering the reactor above the level of the particle bed inside the reactor. The tubes are inclined downward at their outer ends so that coal particles introduced into the tubes through an aperture at the top of the tubes slides downward away from the reactor and does not fall directly into the reactor. Pressurized gas introduced into, or resulting from ignition of recycled combustible gas in a chamber adjacent to the tube ends, propels the coal from the tube into the reactor volume and onto the particle bed. Leveling of the top of the bed is carried out by a bladed rotor mounted on the reactor stirring shaft. Coal is introduced into the tubes from containers above the tubes by means of rotary valves placed across supply conduits. This system avoids placement of feeder hardware in the plenum above the particle bed and keeps the coal from being excessively heated prior to reaching the particle bed.

Notestein, J.E.; Halow, J.S.

1991-12-31T23:59:59.000Z

35

Impact of a vortex ring on a density interface using a regularized inviscid vortex sheet method  

Science Conference Proceedings (OSTI)

A new, fully three-dimensional, vortex-in-cell method designed to follow the unsteady motion of inviscid vortex sheets with or without small (Boussinesq) density discontinuities is presented. As is common in front-tracking methods, the vortex sheet is ... Keywords: Density discontinuity, Stratified flow, Vortex methods, Vortex sheet dynamics, Vortex-in-cell

Mark J. Stock; Werner J. A. Dahm; Grétar Tryggvason

2008-11-01T23:59:59.000Z

36

Performance Study on Multilevel Hybrid Power System of Pneumatic-fuel Vehicle  

Science Conference Proceedings (OSTI)

Put forward the concept of multilevel hybrid power system of pneumatic-Fuel Vehicle, composed of the gasoline engine and pneumatic motor which is droved by the admixture of compressed air and engine exhaust gas so as to improve the dynamics. The dynamics ... Keywords: fuel-pneumatic, multilevel hybrid power vehicle, dynamics, fuel consumption

Wang Guo-ye; Zhang Juan-li; Chou Xiao-gang; Wang Jun; Zheng Chang-song

2011-01-01T23:59:59.000Z

37

Vortex lattices in layered superconductors  

Science Conference Proceedings (OSTI)

We study vortex lattices in a superconductor--normal-metal superlattice in a parallel magnetic field. Distorted lattices, resulting from the shear deformations along the layers, are found to be unstable. Under field variation, nonequilibrium configurations undergo an infinite sequence of continuous transitions, typical for soft lattices. The equilibrium vortex arrangement is always a lattice of isocell triangles, without shear.

Prokic, V. (Department of Physics, University of Belgrade, P.O. Box 368, 11001 Belgrade (Yugoslavia)); Davidovic, D. (Department of Physics and Astronomy, The Johns Hopkins University, Bloomberg Center, Baltimore, Maryland 21218 (United States) Institute of Physics, P.O. Box 57, 11001 Belgrade (Yugoslavia)); Dobrosavljevic-Grujic, L. (Institute of Physics, P.O. Box 57, 11001 Belgrade (Yugoslavia))

1995-03-01T23:59:59.000Z

38

Low NOx Advanced Vortex Combustor  

SciTech Connect

A lean-premixed advanced vortex combustor (AVC) has been developed and tested. The natural gas fueled AVC was tested at the U.S. Department of Energy’s National Energy Technology Laboratory in Morgantown, WV. All testing was performed at elevated pressures and inlet temperatures and at lean fuel-air ratios representative of industrial gas turbines. The improved AVC design exhibited simultaneous NOx /CO/unburned hydrocarbon (UHC) emissions of 4/4/0 ppmv (all emissions corrected to 15% O2 dry). The design also achieved less than 3 ppmv NOx with combustion efficiencies in excess of 99.5%. The design demonstrated marked acoustic dynamic stability over a wide range of operating conditions, which potentially makes this approach significantly more attractive than other lean-premixed combustion approaches. In addition, the measured 1.75% pressure drop is significantly lower than conventional gas turbine combustors, which could translate into an overall gas turbine cycle efficiency improvement. The relatively high velocities and low pressure drop achievable with this technology make the AVC approach an attractive alternative for syngas fuel applications.

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

2008-05-01T23:59:59.000Z

39

Variable residence time vortex combustor  

DOE Patents (OSTI)

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

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

1987-01-01T23:59:59.000Z

40

Vortex–Vortex Interactions in the Winter Stratosphere  

Science Conference Proceedings (OSTI)

This paper examines the interaction of oppositely signed vortices in the compressible (non-Boussinesq) quasigeostrophic system, with a view to understanding vortex interactions in the polar winter stratosphere. A series of simplifying ...

R. K. Scott; D. G. Dritschel

2006-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

The Stability and Genesis of Rossby Vortices  

Science Conference Proceedings (OSTI)

The stability and genesis of the vortices associated with long solitary divergent Rossby waves-the Rossby vortices–are studied numerically using the single-layer (SL) model with Jovian parameters. Vortex behavior depends on location and on ...

Gareth P. Williams; R. John Wilson

1988-01-01T23:59:59.000Z

42

Direct Imaging of Antiferromagnetic Vortex States  

NLE Websites -- All DOE Office Websites (Extended Search)

unique properties for the AFM vortex state. Recently, a research team from Berkeley, Korea, and China has taken the first direct image of an AFM vortex in multilayered magnetic...

43

The synchronous force control of a double-axial pneumatic actuating system  

Science Conference Proceedings (OSTI)

This paper presents the design of the synchronous force controller of a double-axial pneumatic actuating system. This system is ideally decomposed into two independent subsystems, and the coupling effect is considered as the noise effect. So, each ... Keywords: STC, double-axial pneumatic system, synchronous force control

Ying-Tsai Wang; Ming-Kun Chang

1999-07-01T23:59:59.000Z

44

Vortex ice in nanostructured superconductors  

SciTech Connect

We demonstrate using numerical simulations of nanostructured superconductors that it is possible to realize vortex ice states that are analogous to square and kagome ice. The system can be brought into a state that obeys either global or local ice rules by applying an external current according to an annealing protocol. We explore the breakdown of the ice rules due to disorder in the nanostructure array and show that in square ice, topological defects appear along grain boundaries, while in kagome ice, individual defects appear. We argue that the vortex system offers significant advantages over other artificial ice systems.

Reichhardt, Charles [Los Alamos National Laboratory; Reichhardt, Cynthia J [Los Alamos National Laboratory; Libal, Andras J [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

45

Transformed Eliassen Balanced Vortex Model  

Science Conference Proceedings (OSTI)

We consider the axisymmetric balanced flow occurring in a thermally forced vortex in which the frictional inflow is confined to a thin boundary layer. Above the boundary layer the absolute angular momentum ½fR2=rv+½fr2 is conserved. We refer to R ...

Wayne H. Schubert; James J. Hack

1983-06-01T23:59:59.000Z

46

A pneumatic transfer system for special form {sup 252}Cf  

Science Conference Proceedings (OSTI)

A pneumatic transfer system has been developed for use with series 100 Special Form {sup 252}Cf. It was developed to reduce the exposure to personnel handling sources of {sup 252}Cf with masses up to 150 {micro}g by permitting remotely activated two-way transfer between the storage container and the irradiation position. The pneumatic transfer system also permits transfers for reproducible repetitive irradiation periods. In addition to the storage container equipped with quick-release fittings, the transfer system consists of an irradiation station, a control box with momentary contact switches to activate the air-pressure control valves and indicators to identify the location of the source, and connecting air hose and electrical wire. A source of 20 psig air and 110 volt electrical power are required for operation of the transfer system which can be easily moved and set up by one individual in 5 to 10 minutes. Tests have shown that rarely does a source become lodged in the transfer tubing, but two methods have been developed to handle incomplete transfers of the {sup 252}Cf source. The first method consists of closing one air vent to allow a pressure impulse to propel the source to the opposite side. The second method applies to those {sup 252}Cf capsules with a threaded or tapped end to which a small ferromagnetic piece can be attached; an incompletely transferred source in the transfer tube can then be guided to a position of safety by surrounding the transfer tubing containing the capsule with a horseshoe magnet attached to the end of a long pole.

Gehrke, R.J.; Berry, S.M.; Grafwallner, E.G.; Hoggan, J.M.

1996-09-01T23:59:59.000Z

47

Stem control of a sliding-stem pneumatic control valve using a recurrent neural network  

Science Conference Proceedings (OSTI)

This paper presents a neural scheme for controlling an actuator of pneumatic control valve system. Bondgraph method has been used to model the actuator of control valve, in order to compare the response characteristics of valve. The proposed controller ...

Mohammad Heidari, Hadi Homaei

2013-01-01T23:59:59.000Z

48

Design of a pneumatically assisted shifting system for Formula SAE® racing applications  

E-Print Network (OSTI)

An improved shifting system for use with the MIT Formula SAE race car was designed in order to provide drivers with a faster and easier means of shifting. The result of this design was a pneumatic shifting system weighing ...

Kennett, Andrew J. (Andrew John)

2008-01-01T23:59:59.000Z

49

Investigation into the cause of pneumatic actuator failure on the HypoSurface  

E-Print Network (OSTI)

An investigation into the failure of pneumatic actuators on the HypoSurface was conducted to provide information on the current HypoSurface prototype. Using a systematic approach throughout testing, piston components were ...

Chun, Darren M. K. (Darren Masayasu Kekoa)

2007-01-01T23:59:59.000Z

50

ANALYTICAL STUDY OF SOME ASPECTS OF VORTEX TUBES FOR GAS-PHASE FISSION HEATING  

DOE Green Energy (OSTI)

Several problems connected with vortex cavity reactors were studied analytically. They include, the generation of high-strength vortices by utilization of bleed through a porous tube wall to stabilize the shear layer on the wall; the nuclear criticality problem; the suitability of various compounds of plutonium as gaseous fissionable materials; and the problem of retaining the fission fragments within the vortex tube. It is concluded that the shear layer on the vortex tube wall can be stabilized if a mass flow greater than or equal to the vortex through flow is bled through the porous wall, and that the tangential Mach numbers which can be obtained are then slightly more than one-half the inviscid values. Beryllium oxide or graphite-moderated reactors of reasonable size and weight can attain criticality if the product of the hydrogen pressure in the vortex core and the maximum value of the ratio of fissionable gas density to hydrogen density in the tube is greater than about 100 atm. The reactor weights are then in the order of 10,000 lb or less. Of the several compounds of plutonium considered as gaseous fuel carriers, plutonium trifluoride and plutonium tribromide appear to be the most promising. It is probable that they can be held in gaseous form in hydrogen, under the desired concentrations. The rate of loss of fission fragments from the vortex tube can be reduced to a small fraction of the rate of their generation by making the vortex tubes about twice the minimum size that is allowable for satisfactory retention of the fissionable material. (auth)

Kerrebrock, J.L.; Lafyatis, P.G.

1958-07-21T23:59:59.000Z

51

The Effect of Vorticity-Profile Shape on the Instability of a Two-Dimensional Vortex  

Science Conference Proceedings (OSTI)

A simple linear numerical model is used to study the effect of the shape of the vertical vorticity profile on the stability characteristics of a two-dimensional vortex. In all cases, the basic-state vorticity is confined to an annulus. It is ...

Jerry L. Steffens

1988-01-01T23:59:59.000Z

52

Simulations of Dual-Vortex Interaction within Environmental Shear  

Science Conference Proceedings (OSTI)

For over a century it has been known that each vortex in a multiple vortex configuration will move in response to the other vortices. However, despite advances since that time, the complexities of multiple vortex scenarios when sheared ...

Robert E. Hart; Jenni L. Evans

1999-11-01T23:59:59.000Z

53

Stabilizing the Semilocal String with a Dilatonic Coupling  

E-Print Network (OSTI)

We demonstrate that the stability of the semilocal vortex can be significantly improved by the presence of a dilatonic coupling of the form e^\\frac{q | \\Phi |^2}{\\eta^2} F_{\\mu \

Perivolaropoulos, Leandros

2013-01-01T23:59:59.000Z

54

The idea of vortex energy  

E-Print Network (OSTI)

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

V. E. Shapiro

2011-09-12T23:59:59.000Z

55

Stable optical vortex solitons in pair plasmas  

Science Conference Proceedings (OSTI)

It is shown that the pair plasmas with small temperature asymmetry can support existence of localized as well as delocalized optical vortex solitons. Coexistence of such solitons is possible due to peculiar form of saturating nonlinearity which has a focusing-defocusing nature--for weak amplitudes being focusing becoming defocusing for higher amplitudes. It is shown that delocalized vortex soliton is stable in entire region of its existence while single- and multicharged localized vortex solitons are unstable for low amplitudes and become stable for relativistic amplitudes.

Berezhiani, V. I.; Shatashvili, N. L. [Plasma Physics Department, Andronikashvili Institute of Physics, Tbilisi 0177 (Georgia); Department of Physics, Faculty of Exact and Natural Sciences, Javakhishvili Tbilisi State University, Tbilisi 0128 (Georgia); Mahajan, S. M. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)

2010-05-15T23:59:59.000Z

56

Quantitative characterization of pulverized coal and biomasscoal blends in pneumatic conveying pipelines using electrostatic sensor arrays and data fusion techniques  

E-Print Network (OSTI)

Quantitative characterization of pulverized coal and biomass­coal blends in pneumatic conveying.1088/0957-0233/23/8/085307 Quantitative characterization of pulverized coal and biomass­coal blends in pneumatic conveying pipelines using Quantitative data about the dynamic behaviour of pulverized coal and biomass­coal blends in fuel injection

Yan, Yong

57

The use of automation with the new pneumatic irradiation facility of the ORNL HFIR  

Science Conference Proceedings (OSTI)

The High Flux Isotope Reactor at Oak Ridge National Laboratory has two pneumatic irradiation systems: PT-1 installed in 1970 and PT-2 installed in 1987, which are used for neutron activation analysis. Both systems have been described in the literature. By means of a Gould programmable controller, considerable progress has been made in a cost-effective manner to operate and automate the features of the new facility. A neutron counter is an integral part of the new pneumatic tube, and all of the hardware is present to enable automated delayed neutron counting. Some automation of the old system has also been accomplished by the use of a Zymark general purpose programmable robot. This paper describes the automated features of both systems. The reactor has been shut down for safety evaluation since November 1986, so that no irradiations have been made in the new pneumatic tube.

Dyer, F.F.; Robinson, L.; Emery, J.F. (Oak Ridge National Lab., TN (USA))

1988-01-01T23:59:59.000Z

58

Vortex Breakdown in Atmospheric Columnar Vortices  

Science Conference Proceedings (OSTI)

Vortex breakdown occurs in tornadoes and waterspouts. This phenomenon may give information on the state and future behavior of those whirlwinds. Because of the rarity of recorded events, archival sources are consulted for qualitative descriptions ...

H. J. Lugt

1989-12-01T23:59:59.000Z

59

Bubble Behavior in a Taylor Vortex  

E-Print Network (OSTI)

We present an experimental study on the behavior of bubbles captured in a Taylor vortex. The gap between a rotating inner cylinder and a stationary outer cylinder is filled with a Newtonian mineral oil. Beyond a critical ...

Deng, Rensheng

60

Barotropic Vortex Evolution on a Beta Plane  

Science Conference Proceedings (OSTI)

A barotropic, primitive equation (shallow water) model is used on the beta plane to investigate the influence of divergence, total relative angular momentum (RAM) and advective nonlinearities on the evolution of a hurricane-like vortex. The ...

Lloyd J. Shapiro; Katsuyuki V. Ooyama

1990-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Vortex Hydro Energy - National Renewable Energy Laboratory  

Vortex Hydro Energy, LLC Michael M. Bernitsas Ph.D., CEO and CTO Gus Simiao MSE, MBA, Dir. of Business Development NREL’s 20th Annual, Industry Growth Forum

62

Vortex-Driven Sensitivity in Deformation Flow  

Science Conference Proceedings (OSTI)

A sensitivity mechanism for the interaction of two vortices in a two-dimensional deformation background flow is explored. A nonlinear model describing the vortex interaction up to a critical merging distance is developed. This model shows that in ...

Zhiyuan Liu; Paul J. Roebber

2008-12-01T23:59:59.000Z

63

Direct Imaging of Antiferromagnetic Vortex States  

NLE Websites -- All DOE Office Websites (Extended Search)

Direct Imaging of Antiferromagnetic Vortex States Print Direct Imaging of Antiferromagnetic Vortex States Print Magnetic materials are characterized by the ordering of electron spins, with nearest-neighbor spins parallel to each other in ferromagnetic (FM) materials and antiparallel to each other in antiferromagnetic (AFM) materials. As the size of a magnetic system is reduced to micron scale, it has been shown that the spins in an FM microstructure can curl around to form a magnetic vortex state. While there has been intensive activity in the study of vortex states in FM disks, there has been no direct observation of such states in an AFM microstructure, although theory predicts many interesting and unique properties for the AFM vortex state. Recently, a research team from Berkeley, Korea, and China has taken the first direct image of an AFM vortex in multilayered magnetic disk structures using x-ray magnetic linear dichroism (XMLD) and photoemission electron microscopy (PEEM) at ALS Beamlines 4.0.2 and 11.0.1 , respectively. The experiments observed two types of AFM vortices, one of which has no analogue in FM vortices.

64

Direct Imaging of Antiferromagnetic Vortex States  

NLE Websites -- All DOE Office Websites (Extended Search)

Direct Imaging of Antiferromagnetic Vortex States Print Direct Imaging of Antiferromagnetic Vortex States Print Magnetic materials are characterized by the ordering of electron spins, with nearest-neighbor spins parallel to each other in ferromagnetic (FM) materials and antiparallel to each other in antiferromagnetic (AFM) materials. As the size of a magnetic system is reduced to micron scale, it has been shown that the spins in an FM microstructure can curl around to form a magnetic vortex state. While there has been intensive activity in the study of vortex states in FM disks, there has been no direct observation of such states in an AFM microstructure, although theory predicts many interesting and unique properties for the AFM vortex state. Recently, a research team from Berkeley, Korea, and China has taken the first direct image of an AFM vortex in multilayered magnetic disk structures using x-ray magnetic linear dichroism (XMLD) and photoemission electron microscopy (PEEM) at ALS Beamlines 4.0.2 and 11.0.1 , respectively. The experiments observed two types of AFM vortices, one of which has no analogue in FM vortices.

65

Direct Imaging of Antiferromagnetic Vortex States  

NLE Websites -- All DOE Office Websites (Extended Search)

Direct Imaging of Antiferromagnetic Vortex States Print Direct Imaging of Antiferromagnetic Vortex States Print Magnetic materials are characterized by the ordering of electron spins, with nearest-neighbor spins parallel to each other in ferromagnetic (FM) materials and antiparallel to each other in antiferromagnetic (AFM) materials. As the size of a magnetic system is reduced to micron scale, it has been shown that the spins in an FM microstructure can curl around to form a magnetic vortex state. While there has been intensive activity in the study of vortex states in FM disks, there has been no direct observation of such states in an AFM microstructure, although theory predicts many interesting and unique properties for the AFM vortex state. Recently, a research team from Berkeley, Korea, and China has taken the first direct image of an AFM vortex in multilayered magnetic disk structures using x-ray magnetic linear dichroism (XMLD) and photoemission electron microscopy (PEEM) at ALS Beamlines 4.0.2 and 11.0.1 , respectively. The experiments observed two types of AFM vortices, one of which has no analogue in FM vortices.

66

Shutter for hydro-pneumatic current flow harnessing system  

SciTech Connect

A water gate for opening and closing a port on a hydrodynamic system for harnessing energy from a water level differential, the water gate is described comprising: a door hinged mounted within the port for rotation about a first horizontal axis; a window disposed in the door above the first horizontal axis; and a shutter mounted to the door for rotation about a second horizontal axis to open and close the window, whereby the shutter is operative under water pressure to rotate to an open position before the door is caused to rotate to an open position by the water pressure. A system for harnessing the energy of current flow or tidal motion of a water body, comprising: two hydro-pneumatic chambers each having an inlet part for the ingress of water into the chamber below the water surface and an outlet port for the egress of water out of the chamber below the water surface; a water gate disposed at each of the ports and movable between open and closed positions in response to a water level differential on opposite sides of the gate, each water gate comprising: a door hinged mounted within the port for rotation about a first horizontal axis at a vertical mid section of the port, each door having a window in an upper portion of the door,and a shutter mounted on the door for rotation about a second horizontal axis to open and close the window; a linkage between the inlet port water gate of each one of the chambers and the outlet port water gate of the other of the chambers such that an inlet and its linked outlet are either both opened or both closed simultaneously for alternately synchronized operation of the inlet and outlet water gates of each chamber; a channel connecting the chamber above the water surface and operative to permit air to move between the chambers in response to a change in water level in the chambers; and means for harnessing the energy of the air moving within the channel.

Gorlov, A.M.

1993-06-29T23:59:59.000Z

67

Environmental sustainability comparison of a hypothetical pneumatic waste collection system and a door-to-door system  

Science Conference Proceedings (OSTI)

Highlights: Black-Right-Pointing-Pointer We compare the environmental sustainability of two MSW collection systems. Black-Right-Pointing-Pointer We evaluate pneumatic and door-to-door collection systems. Black-Right-Pointing-Pointer The greenhouse gas emissions of pneumatic collection are around three times higher. Black-Right-Pointing-Pointer System components are decisive but assumptions on electricity use are also important. Black-Right-Pointing-Pointer Pneumatic collection could provide other benefits over door-to-door system. - Abstract: Waste collection is one of the life cycle phases that influence the environmental sustainability of waste management. Pneumatic waste collection systems represent a new way of arranging waste collection in densely populated urban areas. However, limited information is available on the environmental impacts of this system. In this study, we compare the environmental sustainability of conventional door-to-door waste collection with its hypothetical pneumatic alternative. Furthermore, we analyse whether the size of the hypothetical pneumatic system, or the number of waste fractions included, have an impact on the results. Environmental loads are calculated for a hypothetical pneumatic waste collection system modelled on an existing dense urban area in Helsinki, Finland, and the results are compared to those of the prevailing, container-based, door-to-door waste collection system. The evaluation method used is the life-cycle inventory (LCI). In this study, we report the atmospheric emissions of greenhouse gases (GHG), SO{sub 2} and NO{sub x}. The results indicate that replacing the prevailing system with stationary pneumatic waste collection in an existing urban infrastructure would increase total air emissions. Locally, in the waste collection area, emissions would nonetheless diminish, as collection traffic decreases. While the electricity consumption of the hypothetical pneumatic system and the origin of electricity have a significant bearing on the results, emissions due to manufacturing the system's components prove decisive.

Punkkinen, Henna, E-mail: henna.punkkinen@vtt.fi [VTT Technical Research Centre of Finland, Biologinkuja 7, P.O. Box 1000, FI-02044 VTT (Finland); Merta, Elina, E-mail: elina.merta@vtt.fi [VTT Technical Research Centre of Finland, Biologinkuja 7, P.O. Box 1000, FI-02044 VTT (Finland); Teerioja, Nea, E-mail: nea.teerioja@helsinki.fi [University of Helsinki, Department of Economics and Management, Latokartanonkaari 9, P.O. Box 27, FI-00014 HY (Finland); Moliis, Katja, E-mail: katja.moliis@helsinki.fi [University of Helsinki, Department of Economics and Management, Latokartanonkaari 9, P.O. Box 27, FI-00014 HY (Finland); Kuvaja, Eveliina, E-mail: eveliina.kuvaja@helsinki.fi [University of Helsinki, Department of Economics and Management, Latokartanonkaari 9, P.O. Box 27, FI-00014 HY (Finland)

2012-10-15T23:59:59.000Z

68

Nonlinear Motion of a Shallow Water Barotropic Vortex  

Science Conference Proceedings (OSTI)

Nonlinear motions of a shallow water barotropic vortex on a ? plane differ substantially from the analogous linear motions. The nonlinear model described here, in which wavenumber 1–3 asymmetries interact with each other and the mean vortex, ...

H. E. Willoughby

1994-12-01T23:59:59.000Z

69

Interactions between a Submesoscale Anticyclonic Vortex and a Front  

Science Conference Proceedings (OSTI)

The evolution of a submesoscale anticyclonic vortex was observed by high-frequency Doppler radio current meters and satellite radiometers. The vortex formed between two large cyclones to the southwest of Oahu, Hawaii. The radius of the core was ...

Cédric Chavanne; Pierre Flament; Klaus-Werner Gurgel

2010-08-01T23:59:59.000Z

70

A Highly Configurable Vortex Initialization Method for Tropical Cyclones  

Science Conference Proceedings (OSTI)

A highly configurable vortex initialization methodology has been constructed in order to permit manipulation of the initial vortex structure in numerical models of tropical cyclones. By using distinct specifications of the flow in the boundary ...

Eric D. Rappin; David S. Nolan; Sharanya J. Majumdar

71

Case Study of an Orographically Induced Mesoscale Vortex (Denver Cyclone)  

Science Conference Proceedings (OSTI)

Observations taken during the Convection Initiation and Downburst Experiment (CINDE) are used to describe the formation and structure of an orographically induced mesoscale vortex that frequently occurs in northeastern Colorado. This vortex, ...

J. M. Wilczak; T. W. Christian

1990-05-01T23:59:59.000Z

72

A Highly Configurable Vortex Initialization Method for Tropical Cyclones  

Science Conference Proceedings (OSTI)

A highly configurable vortex initialization methodology has been constructed in order to permit manipulation of the initial vortex structure in numerical models of tropical cyclones. By using distinct specifications of the flow in the boundary ...

Eric D. Rappin; David S. Nolan; Sharanya J. Majumdar

2013-10-01T23:59:59.000Z

73

Vortex Hydro Energy LLC | Open Energy Information  

Open Energy Info (EERE)

Hydro Energy LLC Hydro Energy LLC Jump to: navigation, search Name Vortex Hydro Energy LLC Address 4870 West Clark Rd Suite 108 Place Ypsilanti Zip 48197 Sector Marine and Hydrokinetic Phone number 734.971.4020 Website http://www.vortexhydroenergy.c Region United States LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This company is listed in the Marine and Hydrokinetic Technology Database. This company is involved in the following MHK Projects: Marine Hydrodynamics Laboratory at the University of Michigan This company is involved in the following MHK Technologies: Vortex Induced Vibrations Aquatic Clean Energy VIVACE This article is a stub. You can help OpenEI by expanding it. Retrieved from "http://en.openei.org/w/index.php?title=Vortex_Hydro_Energy_LLC&oldid=678497

74

A Study of Premixed Propagating Flame Vortex Interaction  

Science Conference Proceedings (OSTI)

Experimental data is presented for the interaction between a propagating flame and a simple vortex flow field structure generated in the wake of solid obstacles. The interaction between gas movement and obstacles creates vortex shedding forming a simple ... Keywords: Combustion, Flame/Vortex, PIV, Visualization

G. K. Hargrave; S. Jarvis

2006-04-01T23:59:59.000Z

75

Entanglement of a Quantum Optical Elliptic Vortex  

E-Print Network (OSTI)

We calculate the entanglement of a generalized elliptical vortex formed by quantized radiation field, using Wigner quasiprobability distribution function for such states. We find a critical squeezing parameter above which the entanglement is less for higher vorticity, which is counter intuitive.

Abir Bandyopadhyay; Shashi Prabhakar; Ravindra Pratap Singh

2010-10-19T23:59:59.000Z

76

Entanglement of Quantum Optical Elliptic Vortex  

E-Print Network (OSTI)

We calculate the entanglement of a generalized elliptical vortex formed by quantized radiation field, using Wigner quasiprobability distribution function for such states. We find a critical squeezing parameter above which the entanglement is less for higher vorticity, which is counter intuitive.

Bandyopadhyay, Abir; Singh, Ravindra Pratap

2010-01-01T23:59:59.000Z

77

Controlled Vortex Breakdown on Modified Delta Wings  

Science Conference Proceedings (OSTI)

This paper studies the effect of perturbation to the breakdown of the leading-edge vortices over delta wings. The passive perturbation in the normal direction is achieved by installing the hemisphere-like bulges on the delta wing along the projection ... Keywords: Bulge perturbation, Delta wing, Vortex breakdown

S. Srigrarom; N. Lewpiriyawong

2007-08-01T23:59:59.000Z

78

The Tornadic Vortex Signature: An Update  

Science Conference Proceedings (OSTI)

A tornadic vortex signature (TVS) is a degraded Doppler velocity signature of a tornado that occurs when the core region of a tornado is smaller than the half-power beamwidth of the sampling Doppler radar. Soon after the TVS was discovered in the ...

Rodger A. Brown; Vincent T. Wood

2012-04-01T23:59:59.000Z

79

Vortex operators in gauge field theories  

SciTech Connect

Several related aspects of the 't Hooft vortex operator are studied. The current picture of the vacuum of quantum chromodynamics, the idea of dual field theories, and the idea of the vortex operator are reviewed first. The Abelian vortex operator written in terms of elementary fields and the calculation of its Green's functions are considered. A two-dimensional solvable model of a Dirac string is presented. The expression of the Green's functions more neatly in terms of Wu and Yang's geometrical idea of sections is addressed. The renormalization of the Green's functions of two kinds of Abelian looplike operators, the Wilson loop and the vortex operator, is studied; for both operators only an overall multiplicative renormalization is needed. In the case of the vortex this involves a surprising cancellation. Next, the dependence of the Green's functions of the Wilson and 't Hooft operators on the nature of the vacuum is discussed. The cluster properties of the Green's functions are emphasized. It is seen that the vortex operator in a massive Abelian theory always has surface-like clustering. The form of Green's functions in terms of Feynman graphs is the same in Higgs and symmetric phases; the difference appears in the sum over all tadpole trees. Finally, systems having fields in the fundamental representation are considered. When these fields enter only weakly into the dynamics, a vortex-like operator is anticipated. Any such operator can no longer be local looplike, but must have commutators at long range. A U(1) lattice gauge theory with two matter fields, one singly charged (fundamental) and one doubly charged (adjoint), is examined. When the fundamental field is weakly coupled, the expected phase transitions are found. When it is strongly coupled, the operator still appears to be a good order parameter, a discontinuous change in its behavior leads to a new phase transition. 18 figures.

Polchinski, J.

1980-07-01T23:59:59.000Z

80

The dependence of chemistry on the inlet equivalence ratio in vortex-flame interactions [Printed LBNL report with title: The effect of stoichiometry on vortex flame interactions  

E-Print Network (OSTI)

of stoichiometry on vortex flame interactions [31] Pember,Rosalik, M . E . , Combust. Flame, 112(3):342-358 (1998).of stoichiometry on vortex flame interactions [15] Mueller,

Tonse, Shaheen R.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

The dependence of chemistry on the inlet equivalence ratio in vortex-flame interactions [Printed LBNL report with title: The effect of stoichiometry on vortex flame interactions  

E-Print Network (OSTI)

of stoichiometry on vortex flame interactions [31] Pember,Rosalik, M . E . , Combust. Flame, 112(3):342-358 (1998).of stoichiometry on vortex flame interactions [15] Mueller,

Bell, John B.; Brown, Nancy J.; Day, Marcus S.; Frenklach, Michael; Grcar, Joseph F.; Tonse, Shaheen R.

1999-01-01T23:59:59.000Z

82

Persistence of Metastable Vortex Lattice Domains in MgB2 in the Presence of Vortex Motion  

Science Conference Proceedings (OSTI)

Recently, extensive vortex lattice metastability was reported in MgB2 in connection with a second-order rotational phase transition. However, the mechanism responsible for these well-ordered metastable vortex lattice phases is not well understood. Using small-angle neutron scattering, we studied the vortex lattice in MgB2 as it was driven from a metastable to the ground state through a series of small changes in the applied magnetic field. Our results show that metastable vortex lattice domains persist in the presence of substantial vortex motion and directly demonstrate that the metastability is not due to vortex pinning. Instead, we propose that it is due to the jamming of counterrotated vortex lattice domains which prevents a rotation to the ground state orientation.

Rastovski, Catherine [University of Notre Dame, IN; Schlesinger, Kimberly [University of Notre Dame, IN; Gannon, William J [Northwestern University, Evanston; Dewhurst, Charles [Institut Laue-Langevin (ILL); Debeer-Schmitt, Lisa M [ORNL; Zhigadlo, Nikolai [ETH Zurich, Switzerland; Karpinski, Janusz [ETH Zurich, Switzerland; Eskildsen, Morten [University of Notre Dame, IN

2013-01-01T23:59:59.000Z

83

A Vortex Contactor for Carbon Dioxide Separations  

NLE Websites -- All DOE Office Websites (Extended Search)

Vortex Contactor for Carbon Dioxide Separations Vortex Contactor for Carbon Dioxide Separations Kevin T. Raterman (ratekt@inel.gov; 208-526-5444) Michael McKellar (mgq@inel.gov; 208-526-1346) Anna Podgorney (poloak@inel.gov; 208-526-0064) Douglas Stacey (stacde@inel.gov; 208-526-3938) Terry Turner (tdt@inel.gov; 208-526-8623) Idaho National Engineering and Environmental Laboratory P.O. Box 1625 Idaho Falls, Idaho 83415-2110 Brian Stokes (bxs9@pge.com; 415-972-5591) John Vranicar (jjv2@pge.com; 415-972-5591) Pacific Gas & Electric Company 123 Mission Street San Francisco, CA 94105 Introduction Many analysts 1,2,3 identify carbon dioxide (CO 2 ) capture and separation as a major roadblock in efforts to cost effectively mitigate greenhouse gas emissions via sequestration. An assessment 4 conducted by the International Energy Agency (IEA)

84

Vortex Dynamics in NanoScale Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Into the Vortex: Dynamics in Nanoscale Materials Into the Vortex: Dynamics in Nanoscale Materials Micron and nanosized magnets are of great interest for their potential applications in new electronic devices, such as magnetic random access memories. As the size of magnets is reduced to a 1-micron scale and below, the boundaries (surfaces, perimeters, etc) of the objects begin to profoundly influence both the static and dynamic behavior of the materials. Researchers from Argonne's Materials Science Division (MSD), Center for Nanoscale Materials (CNM), and Advanced Photon Source (APS) have recently examined the dynamics of 3- to 7-micron-diameter NiFe alloy disks with a combination of theoretical calculations and a new time-resolved magnetic imaging technique using synchrotron-based x-ray photoemission electron

85

Vortex formation during rf heating of plasma  

SciTech Connect

Experiments on a test plasma show that the linear theory of waveguide coupling to slow plasma waves begins to break down if the rf power flux exceeds approx. 30 W/cm/sup 2/. Probe measurements reveal that within 30 ..mu..s an undulation appears in the surface plasma near the mouth of the twin waveguide. This surface readjustment is part of a vortex, or off-center convective cell, driven by asymmetric rf heating of the plasma column.

Motley, R.W.

1980-05-01T23:59:59.000Z

86

Vortex flow visualization using tetrahedral cell subdivision  

Science Conference Proceedings (OSTI)

Proposes an effective technique for searching for critical points, which are points at which the velocity vector is zero. The previous method, using tetrahedral-cell subdivision, often generates multiple critical points in a hexahedral cell, and this ... Keywords: Newton's method, critical point searching technique, hexahedral cell, linear interpolation function, multiple critical points, numerical integration scheme, precise position calculation, tetrahedral cell subdivision, trilinear interpolation function, velocity vector, vortex flow visualization, vortices

A. Doi; S. Suzuki; K. Koyamada; S. Sannakanishi

1997-10-01T23:59:59.000Z

87

QCD String as Vortex String in Seiberg-Dual Theory  

E-Print Network (OSTI)

We construct a classical vortex string solution in a Seiberg-dual theory of N=1 supersymmetric SO(N_c) QCD which flows to a confining phase. We claim that this vortex string is a QCD string, as previouly argued by M.Strassler. In SO(N_c) QCD, it is known that stable QCD strings exist even in the presence of dynamical quarks. We show that our vortex strings are stable in the Seiberg-dual theory.

Eto, Minoru; Terashima, Seiji

2007-01-01T23:59:59.000Z

88

Spontaneous Symmetry-Breaking and the Vortex Lattice ...  

Science Conference Proceedings (OSTI)

... The magnetic vortex lattice of Type-II superconductors, as a quasi ... morphology in single-crystals of pure niobium, a 'conventional' superconductor. ...

89

Development of the prototype pneumatic transfer system for ITER neutron activation system  

SciTech Connect

The neutron activation system (NAS) measures neutron fluence at the first wall and the total neutron flux from the ITER plasma, providing evaluation of the fusion power for all operational phases. The pneumatic transfer system (PTS) is one of the key components of the NAS for the proper operation of the system, playing a role of transferring encapsulated samples between the capsule loading machine, irradiation stations, counting stations, and disposal bin. For the validation and the optimization of the design, a prototype of the PTS was developed and capsule transfer tests were performed with the developed system.

Cheon, M. S.; Seon, C. R.; Pak, S.; Lee, H. G. [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Bertalot, L. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France)

2012-10-15T23:59:59.000Z

90

Thin, X-ray-Transparent Windows for Imaging Applications with a Pneumatically Pressurized Enclosure  

SciTech Connect

We have developed a novel thin, x-ray-transparent window system for environmental chambers involving pneumatic pressures above 10 bar. The windows allow for x-ray access to fuel sprays injected into a pressurized chamber that mimics realistic internal combustion engine cylinder operating conditions. The design of the window system and its experimental test results are presented in this paper, as well as its further development for in situ x-ray imaging applications in a high-pressure and high-temperature environment.

Shu Deming; Wang Jin; Preissner, Curt [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States)

2007-01-19T23:59:59.000Z

91

Principles of equilibrium statistical mechanics revisited: The idea of vortex energy  

E-Print Network (OSTI)

We show that the law of energy conservation with the fact of matter stability imply the existence of energy complementary to that given by the function of states of interacting systems and treated, with the environment, the function of states of interacting extended systems. The complementary energy, we called it vortex, is integral, not quantized, and causes trends contrary to that prescribed by equilibrium statistical mechanics. We formulate its principles and theorems, and question traditional insights in thermodynamics, entropy law, phase transitions, persistent currents, Brownian motion.

V. E. Shapiro

2013-05-21T23:59:59.000Z

92

Water gate array for current flow or tidal movement pneumatic harnessing system  

DOE Patents (OSTI)

The invention, which provides a system for harnessing power from current flow or tidal movement in a body of water, comprises first and second hydro-pneumatic chambers each having ingress and egress below the water surface near the river or ocean floor and water gates operative to open or seal the ports to the passage of water. In an exemplary embodiment, the gates are sychronized by shafts so that the ingress ports of each chamber are connected to the egress ports of each other chamber. Thus, one set of gates is closed, while the other is open, thereby allowing water to flow into one chamber and build air pressure therein and allowing water to flow out of the other chamber and create a partial vacuum therein. A pipe connects the chambers, and an air turbine harnesses the air movement within the pipe. When water levels are equilibrated, the open set of gates is closed by a counterweight, and the other set is allowed to open by natural force of the water differential. The water gates may be comprised of a plurality of louvers which are ganged for simultaneous opening and closing. The system is designed to operate with air turbines or other pneumatic devices. Its design minimizes construction cost and environmental impact, yet provides a clean renewable energy source.

Gorlov, Alexander M. (Brookline, MA)

1991-01-01T23:59:59.000Z

93

Fabrication, assembly, bench and drilling tests of two prototype downhole pneumatic turbine motors: Final technical report  

DOE Green Energy (OSTI)

The first and second prototype downhole pneumatic turbine motors have been fabricated, assembled and tested. All bench tests showed that the motor will produce horsepower and bit speeds approximating the predicted values. Specifically, the downhole pneumatic turbine motor produced approximately 50 horsepower at 100 rpm, while being supplied with about 3600 SCFM of compressed air. The first prototype was used in a drilling test from a depth of 389 feet to a depth of 789 feet in the Kirtland formation. This first prototype motor drilled at a rate exceeding 180 ft/hr, utilizing only 3000 SCFM of compressed air. High temperature tests (at approximately 460/sup 0/F) were carried out on the thrust assembly and the gearboxes for the two prototypes. These components operated successfully at these temperatures. Although the bench and drilling tests were successful, the tests revealed design changes that should be made before drilling tests are carried out in geothermal boreholes at the Geysers area, near Santa Rosa, California.

Bookwalter, R.; Duettra, P.D.; Johnson, P.; Lyons, W.C.; Miska, S.

1987-04-01T23:59:59.000Z

94

Magnetic Vortex Core Reversal by Low-Field Excitations  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Vortex Core Reversal by Magnetic Vortex Core Reversal by Low-Field Excitations Magnetic Vortex Core Reversal by Low-Field Excitations Print Wednesday, 28 March 2007 00:00 In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very strong magnetic fields of around half a tesla (approximately one-third the field of the strongest permanent magnet) were previously thought to be necessary to accomplish this. At the ALS, a team of researchers from Germany, Belgium, and the U.S. has used time-resolved scanning transmission x-ray microscopy (STXM) to observe vortex motion and demonstrate the feasibility of using weak magnetic fields as low as 1.5 millitesla (mT) to reverse the direction of a vortex core. The observed switching mechanism, which can be understood within the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application to data storage technologies.

95

Structure of quantum vortex tangle in He-4 counterflow turbulence  

E-Print Network (OSTI)

The main goal of this paper is to present a comprehensive characterization of well developed vortex tangles in a turbulent counterflow in quantum fluids (with a laminar normal fluid component). We analyze extensive numerical simulations using the vortex filament method, solving the full Biot-Savart equations for the vortex dynamics in a wide range of temperatures and counter-flow velocities. In addition to a detailed analysis of traditional characteristics such as vortex line density, anisotropic and curvature parameters of the vortex tangle, we stress other dynamical and statistical characteristics which are either much less studied or even unstudied. The latter include reconnection rates, mean mutual friction forces, drift velocities and the probability distribution functions of various tangle parameters: the loop length, the line curvature, the mean curvature of loops with a given length, etc. During these studies we compare the three main reconnection procedures which are widely used in the literature, and identify which properties are strongly affected by the choice of the reconnection criteria and which of them are practically insensitive to the reconnection procedure. The conclusion is that the vortex filament method in the framework of the Biot-Savart equation sufficiently robust and well suited for the description of the steady state vortex tangle in a quantum counterflow. The Local-Induction Approximation to this equation may be successfully used to analytically establish relationships between mean characteristics of the stochastic vortex tangle.

Luiza Kondaurova; Victor L'vov; Anna Pomyalov; Itamar Procaccia

2013-06-26T23:59:59.000Z

96

Helicoidal vortex model for wind turbine aeroelastic simulation  

Science Conference Proceedings (OSTI)

The vortex method has been extended to account for blade flexibility, which is a potential source of unsteadiness in the flow past a wind turbine rotor. The code has been validated previously under the assumption of rigid blades. The aerodynamics method ... Keywords: Blade flexibility, Steady and unsteady flows, Tower interference, Vortex model

Jean-Jacques Chattot

2007-06-01T23:59:59.000Z

97

Finned Tube With Vortex Generators For A Heat Exchanger.  

DOE Patents (OSTI)

A system for and method of manufacturing a finned tube for a heat exchanger is disclosed herein. A continuous fin strip is provided with at least one pair of vortex generators. A tube is rotated and linearly displaced while the continuous fin strip with vortex generators is spirally wrapped around the tube.

Sohal, Monohar S. (Idaho Falls, ID); O' Brien, James E. (Idaho Falls, ID)

2004-09-14T23:59:59.000Z

98

Finned Tube With Vortex Generators For A Heat Exchanger.  

DOE Patents (OSTI)

A system for and method of manufacturing a finned tube for a heat exchanger is disclosed herein. A continuous fin strip is provided with at one pair of vortex generators. A tube is rotated and linearly displaced while the continuous fin strip with vortex generators is spirally wrapped around the tube.

Sohal, Manohar S. (Idaho Falls, ID); O' Brien, James E. (Idaho Falls, ID)

2005-12-20T23:59:59.000Z

99

An Investigation of a Three-Dimensional Asymmetric Vortex  

Science Conference Proceedings (OSTI)

A three-dimensional numerical simulation is presented for the asymmetric vortex motion which occurs in a Ward-type vortex chamber. The initial state is taken to be one of axisymmetric irrotational flow where the flow enters through the sides at ...

Richard Rotunno

1984-01-01T23:59:59.000Z

100

Gravity waves from vortex dipoles and jets  

E-Print Network (OSTI)

The dissertation first investigates gravity wave generation and propagation from jets within idealized vortex dipoles using a nonhydrostatic mesoscale model. Several initially balanced and localized jets induced by vortex dipoles are examined here. Within these dipoles, inertia-gravity waves with intrinsic frequencies 1-2 times the Coriolis parameter are simulated in the jet exit region. The ray tracing analysis reveals strong variation of wave characteristics along ray paths. The dependence of wave amplitude on the Rossby number is examined through experiments in which the two vortices are initially separated by a large distance but subsequently approach each other and form a vortex dipole with an associated amplifying localized jet. The amplitude of stationary gravity waves in the simulations with a 90-km grid spacing increases nearly linearly with the square of the Rossby number but significantly more rapidly when smaller grid spacing is used. To further address the source mechanism of the gravity waves within the vortex dipole, a linear numerical framework is developed based on the framework proposed by Plougonven and Zhang (2007). Using the nonlinearly balanced fields as the basic state and driven by three types of large scale forcing, the vorticity, divergence and thermodynamic forcing, this linear model is utilized to obtain linear wave responses. The wave packets in the linear responses compare reasonably well with the MM5 simulated gravity waves. It is suggested that the vorticity forcing is the leading contribution to both gravity waves in the jet exit region and the ascent/descent feature in the jet core. This linear model is also adopted to study inertia-gravity waves in the vicinity of a baroclinic jet during the life cycle of an idealized baroclinic wave. It is found that the thermodynamic forcing and the vorticity forcing are equally important to the gravity waves in the low stratosphere, but the divergence forcing is again playing a lesser role. Two groups of wave packets are present in the linear responses; their sources appear to locate either near the surface front or near the middle/upper tropospheric jet.

Wang, Shuguang

2008-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

MHK Technologies/Vortex Induced Vibrations Aquatic Clean Energy VIVACE |  

Open Energy Info (EERE)

Vortex Induced Vibrations Aquatic Clean Energy VIVACE Vortex Induced Vibrations Aquatic Clean Energy VIVACE < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Vortex Induced Vibrations Aquatic Clean Energy VIVACE.jpg Technology Profile Primary Organization Vortex Hydro Energy LLC Project(s) where this technology is utilized *MHK Projects/Marine Hydrodynamics Laboratory at the University of Michigan Technology Resource Click here Current/Tidal Technology Type Click here Reciprocating Device Technology Readiness Level Click here TRL 4: Proof of Concept Technology Description The VIVACE (Vortex Induced Vibrations Aquatic Clean Energy) device is based on the extensively studied phenomenon of Vortex Induced Vibrations (VIV), which was first observed five-hundred years ago by Leonardo DaVinci in the form of 'Aeolian Tones.' VIV results from vortices forming and shedding on the downstream side of a bluff body in a current. Vortex shedding alternates from one side to the other, thereby creating a vibration or oscillation. The VIV phenomenon is non-linear, which means it can produce useful energy at high efficiency over a wide range of current speeds and directions.This converter is unlike any existing technology, as it does not use turbines, propellers, or dams. VIVACE converts the horizontal hydrokinetic energy of currents into cylinder mechanical energy. The latter is then converted to electricity through electric power generators.

102

Magnetic Vortex Core Reversal by Low-Field Excitations  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Vortex Core Reversal by Low-Field Excitations Print Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very strong magnetic fields of around half a tesla (approximately one-third the field of the strongest permanent magnet) were previously thought to be necessary to accomplish this. At the ALS, a team of researchers from Germany, Belgium, and the U.S. has used time-resolved scanning transmission x-ray microscopy (STXM) to observe vortex motion and demonstrate the feasibility of using weak magnetic fields as low as 1.5 millitesla (mT) to reverse the direction of a vortex core. The observed switching mechanism, which can be understood within the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application to data storage technologies.

103

Magnetic Vortex Core Reversal by Low-Field Excitations  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Vortex Core Reversal by Low-Field Excitations Print Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very strong magnetic fields of around half a tesla (approximately one-third the field of the strongest permanent magnet) were previously thought to be necessary to accomplish this. At the ALS, a team of researchers from Germany, Belgium, and the U.S. has used time-resolved scanning transmission x-ray microscopy (STXM) to observe vortex motion and demonstrate the feasibility of using weak magnetic fields as low as 1.5 millitesla (mT) to reverse the direction of a vortex core. The observed switching mechanism, which can be understood within the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application to data storage technologies.

104

Magnetic Vortex Core Reversal by Low-Field Excitations  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetic Vortex Core Reversal by Low-Field Excitations Print Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very strong magnetic fields of around half a tesla (approximately one-third the field of the strongest permanent magnet) were previously thought to be necessary to accomplish this. At the ALS, a team of researchers from Germany, Belgium, and the U.S. has used time-resolved scanning transmission x-ray microscopy (STXM) to observe vortex motion and demonstrate the feasibility of using weak magnetic fields as low as 1.5 millitesla (mT) to reverse the direction of a vortex core. The observed switching mechanism, which can be understood within the framework of micromagnetic theory, gives insights into basic magnetization dynamics and their possible application to data storage technologies.

105

Charging of coal powder particles in dense phase pneumatic conveying system at low pressure  

Science Conference Proceedings (OSTI)

A non-contact measurement method, namely an electrostatic probe, for particle charging characteristics determination is introduced in the paper. Using the probe, the charging trends of the pulverized bituminous coal in a dense phase pneumatic conveying system at low pressure were investigated for gas superficial velocities in a range of 6-10 m/s and particle concentrations in a range of 128-230 kg/m{sup 3}. The observations indicated that increasing the coal particles concentration leads to an increase in charge level of the pulverized coal particles and then a decrease, and a peak of the charge level is experienced in the range of 150-160 kg/m{sup 3}. The charges carried by the coal particles increase with the increase of gas superficial velocity in the pipeline, and then reach saturation values.

Xu, C.L.; Tang, G.H.; Wang, S.M. [Southeast University, Nanjing (China). School of Energy & Environment

2009-04-15T23:59:59.000Z

106

Open loop pneumatic control of a Lysholm engine or turbine exhaust pressure  

DOE Green Energy (OSTI)

A Lysholm engine, or helical screw expander, is currently being evaluated at the University of California, Berkeley for staging with a conventional turbine in geothermal energy conversion. A pneumatic closed loop, proportional-integral control system was implemented to control the Lysholm engine's exhaust pressure for performance testing of the engine at constant inlet/outlet pressure ratios. The control system will also be used to control the exhaust pressure of the conventional turbine during future testing of the staged Lysholm-turbine system. Analytical modeling of the control system was performed and successful tuning was achieved by applying Ziegler-Nichol's tuning method. Stable control and quick response, of approximately 1 minute, was demonstrated for load and set point changes in desired exhaust pressures.

Plonski, B.A.

1981-07-17T23:59:59.000Z

107

Ferroelectric nanostructure having switchable multi-stable vortex states  

DOE Patents (OSTI)

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

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

2009-09-22T23:59:59.000Z

108

Orbit Stability  

NLE Websites -- All DOE Office Websites (Extended Search)

Source Parameter Table Up: APS Storage Ring Parameters Previous: Lattice Definitions Orbit Stability This section lists the specifications of orbit stability. The stored beam...

109

Vortex flow around the bases of obstacles  

E-Print Network (OSTI)

.2 The horseshoe . vortex formed by a separating turbulent boundary layer 5.3 Scour around obstacles in an erodible bed 114 116 117 . ·4 References Uf'l() I:!~oLtlecl F,'obL.efl):' Llr:cl ~u.g5el:dto/J~ fer ju.iLt(t' wc"..,I" 11 2 119 Figures (vi... , are shmm in figUre 2.3.4. It can be seen that there is a rather high le,el of turbulence in the tunnel free stream. This is poss:l.bly due to the extra screens placed upstream of the \\'lorking section. At the higher speeds used this turbulence...

Baker, Christopher James

1979-02-06T23:59:59.000Z

110

The multiple vortex nature of tropical cyclogenesis  

E-Print Network (OSTI)

This thesis contains an observational analysis of the genesis of Tropical Storm Allison (2001). Using a paradigm of tropical cyclone formation as the superposition of potential vorticity (PV) anomalies, the importance of different scales of PV merger to various aspects of Allison?s formation is discussed. While only the case of Allison is discussed in great detail, other studies have also documented PV superposition on various scales, and superposition could be important for most tropical cyclones. Preceding Allison?s genesis, PV superposition on the large scale destabilized the atmosphere and increased low-level cyclonic vorticity. This presented a more favorable environment for the formation of MCV-type PV anomalies and smaller, surface-based, meso-?-scale vortices. Although these vortices eventually merged to form a more concentrated vortex with stronger surface pressure gradients, the merger happened well after landfall of Allison and no strengthening ensued. The unstable, vorticity-rich environment was also favorable for the development of even smaller, meso-?-scale vortices that accompanied deep convective cells within one of Allison?s meso-?-scale vortices. The observations herein suggest that the meso-?- scale convective cells and vortices are the respective source of PV production and building blocks for the meso-?-scale vortices. Finally, this thesis discusses issues related to the multiple vortex nature of tropical cyclone formation. For instance, the tracking of developing tropical cyclones is greatly complicated by the presence of multiple vortices. For these cases, the paradigm of a single cyclone center is inappropriate and alternative tracking methods are introduced.

Sippel, Jason Allen

2004-12-01T23:59:59.000Z

111

Argonne CNM Highlight: Biofunctionalized magnetic-vortex microdiscs for  

NLE Websites -- All DOE Office Websites (Extended Search)

Biofunctionalized magnetic-vortex microdiscs for targeted cancer-cell destruction Biofunctionalized magnetic-vortex microdiscs for targeted cancer-cell destruction Magnetic microdisks Reflection optical microscope image of a dried suspension of the discs prepared via magnetron sputtering and optical lithography. Magnetic spin vortex Model of magnetic-vortex spin distribution in a disc. Users from Argonne's Materials Science Division and University of Chicago's Pritzker School of Medicine, working collaboratively on a user science project with CNM's Nanobio Interfaces Group, have discovered that nanostructured magnetic materials offer exciting avenues for probing cell mechanics, activating mechanosensitive ion channels, and advancing potential cancer therapies. Their new report describes an approach based on interfacing cells with lithographically defined microdiscs (1-micron

112

Magnetic Vortex Core Reversal by Low-Field Excitations  

NLE Websites -- All DOE Office Websites (Extended Search)

on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very strong...

113

Linear Dynamics of the Multiple-Vortex Phenomenon in Tornadoes  

Science Conference Proceedings (OSTI)

The reason for existence of two separate unstable modes, previously described by Gall for flows in vortex simulators, is explored. When the energy equation for an unstable disturbance is considered, it is clear that the most unstable wave must be ...

Robert L. Gall

1985-04-01T23:59:59.000Z

114

Baroclinic Transition of a Long-Lived Mesoscale Convective Vortex  

Science Conference Proceedings (OSTI)

The period 5–15 June 2003, during the field phase of the Bow Echo and Mesoscale Convective Vortex (MCV) Experiment (BAMEX), was noteworthy for the wide variety of mesoscale convective systems (MCSs) that occurred. Of particular interest was a ...

Thomas J. Galarneau Jr.; Lance F. Bosart; Christopher A. Davis; Ron McTaggart-Cowan

2009-02-01T23:59:59.000Z

115

Reexamining the Vertical Development of Tornadic Vortex Signatures in Supercells  

Science Conference Proceedings (OSTI)

Observations from a hybrid phased-array Doppler radar, the Mobile Weather Radar, 2005 X-band, Phased-Array (MWR-05XP), were used to investigate the vertical development of tornadic vortex signatures (TVSs) during supercell tornadogenesis. Data ...

Michael M. French; Howard B. Bluestein; Ivan PopStefanija; Chad A. Baldi; Robert T. Bluth

116

Inertia–Gravity Waves Generated within a Dipole Vortex  

Science Conference Proceedings (OSTI)

Vortex dipoles provide a simple representation of localized atmospheric jets. Numerical simulations of a synoptic-scale dipole in surface potential temperature are considered in a rotating, stratified fluid with approximately uniform potential ...

Chris Snyder; David J. Muraki; Riwal Plougonven; Fuqing Zhang

2007-12-01T23:59:59.000Z

117

Ozone Chemistry during the 2002 Antarctic Vortex Split  

Science Conference Proceedings (OSTI)

In September 2002, the Antarctic polar vortex was disturbed, and it split into two parts caused by an unusually early stratospheric major warming. This study discusses the chemical consequences of this event using the Chemical Lagrangian Model of ...

Jens-Uwe Grooß; Paul Konopka; Rolf Müller

2005-03-01T23:59:59.000Z

118

Assimilating Vortex Position with an Ensemble Kalman Filter  

Science Conference Proceedings (OSTI)

Observations of hurricane position, which in practice might be available from satellite or radar imagery, can be easily assimilated with an ensemble Kalman filter (EnKF) given an operator that computes the position of the vortex in the background ...

Yongsheng Chen; Chris Snyder

2007-05-01T23:59:59.000Z

119

Spontaneous Imbalance and Hybrid Vortex–Gravity Structures  

Science Conference Proceedings (OSTI)

After reviewing the background, this article discusses the recently discovered examples of hybrid propagating structures consisting of vortex dipoles and comoving gravity waves undergoing wave capture. It is shown how these examples fall outside ...

Michael E. McIntyre

2009-05-01T23:59:59.000Z

120

Some Aspects of Vortex Structure Related to Tropical Cyclone Motion  

Science Conference Proceedings (OSTI)

Some effect of tropical cyclone structure on the vortex motion are examined in a nondivergent, barotropic numerical model with no basic current. As suggested earlier by DeMaria, the initial maximum wind speed has little effect on the track. ...

Michael Fiorino; Russell L. Elsberry

1989-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

MHK Technologies/SeaUrchin Vortex Reaction Turbine | Open Energy  

Open Energy Info (EERE)

SeaUrchin Vortex Reaction Turbine SeaUrchin Vortex Reaction Turbine < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage SeaUrchin Vortex Reaction Turbine.jpg Technology Profile Primary Organization Elemental Energy Technologies Limited ABN 46 128 491 903 Technology Resource Click here Current Technology Type Click here Axial Flow Turbine Technology Readiness Level Click here TRL 4 Proof of Concept Technology Description A revolutionary vortex reaction turbine branded the SeaUrchin an advanced third generation marine turbine technology capable of delivering inexpensive small to large scale baseload or predictable electricity by harnessing the kinetic energy of free flowing ocean currents tides and rivers Technology Dimensions Device Testing Date Submitted 55:15.2

122

Closed cycle steam turbine system with liquid vortex pump  

SciTech Connect

A closed cycle steam generating system is described comprising a steam boiler, and a steam turbine includes a vacuum pump of the liquid vortex type for condensing the exhaust steam from the turbine, a feedwater pump being employed for returning the condensate to the boiler. The tank of the vortex pump is maintained filled with water and the pressure in the tank is regulated automatically to maintain a predetermined value thereof.

Brown, K.D.

1976-08-10T23:59:59.000Z

123

Nonclassicality of vortex Airy beams in the Wigner representation  

Science Conference Proceedings (OSTI)

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

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

2011-10-15T23:59:59.000Z

124

Depinning of a superfluid vortex line by Kelvin waves  

E-Print Network (OSTI)

We measure the interaction of a single superfluid vortex with surface irregularities. While vortex pinning in superconductors usually becomes weaker at higher temperatures, we find the opposite behavior. The pinning steadily increases throughout our measurement range, from 0.15Tc to over 0.5Tc. We also find that moving the other end of the vortex decreases the pinning, so we propose Kelvin waves along the vortex as a depinning mechanism. PACS numbers: 67.40.Vs, 74.60.Ge Pinning sites can trap vortices in a variety of systems. In superconductors, where vortex motion leads to nonzero resistance, a vast amount of work has been devoted to preventing such motion by introducing defects. Experimental work has shown that defects comparable in size to the vortex core make effective pin centers, and that straight [1] or splayed [2] line defects can increase the pin strength. Yet the mechanisms by which vortices interact with pin sites remain unresolved. Experimentally, pinning in superconductors becomes weaker as

L. A. K. Donev; L. Hough; R. J. Zieve

2001-01-01T23:59:59.000Z

125

A numerical study of steady-state vortex configurations and vortex pinning in type-II superconductors  

E-Print Network (OSTI)

In part I, a numerical study of the mixed states in a mesoscopic type-II superconducting cylinder is described. Steady-state configurations and transient behavior of the magnetic vortices for various values of the applied magnetic field H are presented. Transitions between different multi-vortex states as H is changed is demonstrated by abrupt changes in vortex configurations and jumps in the B vs H plot. An efficient scheme to determine the equilibrium vortex configuration in a mesoscopic system at any given applied field, not limited to the symmetry of the system, is devised and demonstrated. In part II, a superconducting thin film is subject to a non-uniform magnetic field from a vertical magnetic dipole, consisting of two magnetic monopoles of opposite charges. For a film with constant thickness and with no pins, it has been found that the film carries two pairs of vortex-antivortex in the steady state in the imposed flux range of 2.15 < (Phi)+ < 2.90 (in units of flux quantum) and no vortex at all for (Phi)+ <= 2.15. Transitions from a superconducting state with 3 pairs of vortex-antivortex to one with 2 pairs, where a pair of vortex-antivortex annihilates, have been observed in the pseudo-time sequence. With a perturbation with antidots (holes), vortexantivortex pair has been created for lower magnetic fluxes down to (Phi)+ = 1.3. In the sample of size 16(Xi) x 16(Xi), the attraction force between the vortex and antivortex always dominates over the pinning force, so that they eventually come out of pins, move toward each other, and annihilate each other. The annihilation rate, measured with time taken for the annihilation, is reduced noticeably by the increase of the distance between pins, or the increase in the pin size. A simulation of the magnetic vortex pinning in the sample of size 32(Xi) x 32(Xi) suggests we are likely to achieve pinning of the vortex-antivortex pair with the sample size around this and vortex-antivortex separation of 22(Xi). Using this sample as a template, the maximum density of pinned vortices achievable is calculates to be about 7.6 x 10^14 vortices/m2 for (Xi) =~ 1.6A°.

Kim, Sangbum

2004-12-01T23:59:59.000Z

126

A High Performance Pneumatic Force Actuator System Part 1 - Nonlinear Mathematical Model  

E-Print Network (OSTI)

In this pap er we developed a detailed mathematical model of dual action pneumatic actuator contr16 with pr2 or2520 spool valves. E#ects of nonlinear flowthr35 the valve,air compr6T430035 y incylinder chamber2 leakage between chamber6 end of str1 e inactive volume, and time delay and attenuation in the pneumatic lines wercar14T4 consider6 System identification, numer4T simulation and model validation experT11 ts wer conducted for two types of air cylinder and di#er4 t connecting tubes length, showing ver goodagr552T t. This mathematical model will be used in the development of high per35T423 nonlinear for3 contr330T with applications in teleopereopT1 haptic inter164T and rT otics. 1 Introducti Mode) forceIP(k)fiXe tek## e ration, haptic inte#kP9kX andothe applications in robotics recsX( high pefifiP6XIP# force actuators, with highforce output pe r unit wefi9 t. It is also important to have line96 fast andaccurate reu onse as we# as low friction and me hanical impe dance Traditional gekk9 e lek9#6XI motors can not provide the characteP#BfiBXe Fe w ne## de#(#XI motors may have spek)fi dire)XIB(# e actuators, with no intefi)BB9XI # This ar116 has appear in the September 2000 issue of ASME Jour3 of Dynamic Systems Measur2 ment and ContrT1 Vol. 122, No.3, pp. 416-425 1 me hanisms. YeP applications such astek9( ek9(P maste arms with gravitational compe nsation, rePPfi# long duration, static highforce output. In the6 caseB direB drive e levXfi)(6 actuators nekBB6XI9k speXPB cooling syste) todissipate the e xceipa e hei We be lie e thatpneXP96# cylinde# can o#e a be tte alte9BkXI e toefik)6(XI9 or hydraulic actuators forceXP#B type s of applications. PneP966X actuators provide the preBfifi)XI e umeBfifi) qualitie at low cost. The are alsosuitable forcle# e nvironme ts ands...

Edmond Richer; Yildirim Hurmuzlu

2001-01-01T23:59:59.000Z

127

Energy spectra of the pneumatically positioned neutron sources at LLNL's Hazards control standards and calibration facility  

Science Conference Proceedings (OSTI)

The Hazards Control Department of Lawrence Livermore National Laboratory maintains a Standards and Calibration Laboratory that includes three neutron sources (two /sup 252/Cf and one /sup 238/PuBe that can be positioned pneumatically for irradiations. Ten moderators exist to modify the neutron energy spectra produced by these sources. The thicknesses and materials of these moderators are: 25-cm water; 5-, 10-, 15-, and 25-cm heavy water; 20-cm aluminum; and 2-, 5-, 10-, and 15-cm polyethylene. We used a multisphere spectrometer to measure the neutron spectra at 2 m from both the PuBe source and the smaller Cf source, with the sources bare, and in all of the moderators. These data were reduced in 25 energy groups ranging from 0.25 eV to 16 MeV. Except for the 15-m polyethylene moderator, we also made measurements using a liquid-scintillator fast-neutron spectrometer. These data were reduced in 0.1-MeV increments from 0.5 to 12.5 MeV. Spectra from the measurements and from independent calculations are presented in tabular and graphic form. Dosimetric values, calculated from both the measured and calculated spectra, are also presented.

Thorngate, J.H.

1987-06-15T23:59:59.000Z

128

Laser Doppler Anemometry Measurements of Dilute Pneumatic Transport in a Vertical Lifter  

E-Print Network (OSTI)

Vertical pneumatic transport in a lab-scale vertical lifter has been studied using Laser Doppler Anemometry (LDA). The experimental system consists of a lower fluidized silo, an upper receiving tank and a connecting vertical transport pipe made of clear glass. The experimental study has been performed in order to get detailed information of the complex gas-particle flow behavior in a dilute vertical conveying system. Axial and tangential particle velocities, as well as root mean square velocities are measured simultanously for different flow conditions. The particulate material transported is Zirconium Oxide (ZrO2) solids. Measurements is obtained using transport air flow rate of 24, 36, 48 and 60 m3/h. The air is feeded into the tranport air through a nozzle. The length this nozzle is sticking into the transport pipe is varied in order to study the nozzle position influence on the flow behavior. The receiving tank is equipped with weighing cells, so that solids mass fluxes also can be measured for different flow conditions.

Telemark Technological R; D Centre (tel-tek; Vidar Mathiesen; Vidar Mathiesen; Tron Solberg; Tron Solberg

2000-01-01T23:59:59.000Z

129

Barotropic Simulation of Large-Scale Mixing in the Antarctic Polar Vortex  

Science Conference Proceedings (OSTI)

Theory and observations suggest that the Antarctic polar vortex is relatively isolated from midlatitudes, although others have interpreted the observations to indicate that there is substantial mixing from the interior of the vortex into middle ...

Kenneth P. Bowman

1993-09-01T23:59:59.000Z

130

Stratospheric Sudden Warmings as Self-Tuning Resonances. Part I: Vortex Splitting Events  

Science Conference Proceedings (OSTI)

The fundamental dynamics of “vortex splitting” stratospheric sudden warmings (SSWs), which are known to be predominantly barotropic in nature, are reexamined using an idealized single-layer f-plane model of the polar vortex. The aim is to ...

N. Joss Matthewman; J. G. Esler

2011-11-01T23:59:59.000Z

131

A Theory for Mixed Vortex Rossby–Gravity Waves in Tropical Cyclones  

Science Conference Proceedings (OSTI)

Vortex–Rossby waves (VRWs) and inertial gravity waves (IGWs) have been proposed to explain the propagation of spiral rainbands and the development of dynamical instability in tropical cyclones (TCs). In this study, a theory for mixed vortex–...

Wei Zhong; Da-Lin Zhang; Han-Cheng Lu

2009-11-01T23:59:59.000Z

132

Generation and Propagation of Inertia–Gravity Waves from Vortex Dipoles and Jets  

Science Conference Proceedings (OSTI)

This study investigates gravity wave generation and propagation from jets within idealized vortex dipoles using a nonhydrostatic mesoscale model. Two types of initially balanced and localized jets induced by vortex dipoles are examined here. ...

Shuguang Wang; Fuqing Zhang; Chris Snyder

2009-05-01T23:59:59.000Z

133

Influence of a Strong Bottom Slope on the Evolution of a Surface-Intensified Vortex  

Science Conference Proceedings (OSTI)

The authors investigate the influence of steep bottom topography on the propagation of a vortex in a two-layer quasigeostrophic model. The vortex is intensified in the upper layer and the planetary beta effect is taken into account.

Virginie Thierry; Yves Morel

1999-05-01T23:59:59.000Z

134

Vortex dynamics : a window into the properties of type-II superconductors  

E-Print Network (OSTI)

DIEGO Vortex Dynamics: A Window Into the Properties of Type-DISSERTATION Vortex Dynamics: A Window Into the Propertiesa ?lm deposits on the window through which the laser beam

Taylor, Benjamin Jeremy

2006-01-01T23:59:59.000Z

135

Combining the vortex-in-cell and parallel fast multipole methods for efficient domain decomposition simulations  

Science Conference Proceedings (OSTI)

A new combination of vortex-in-cell and parallel fast multipole methods is presented which allows to efficiently simulate, in parallel, unbounded and half-unbounded vortical flows (flows with one flat wall). In the classical vortex-in-cell (VIC) method, ... Keywords: Incompressible flows, Lagrangian methods, Parallel fast multipole method, Particle methods, Unbounded flows, Unsteady flows, Vortex methods, Vortex-in-cell method, Wall-bounded flows

Roger Cocle; Grégoire Winckelmans; Goéric Daeninck

2008-02-01T23:59:59.000Z

136

The Data Vortex, an All Optical Path Multicomputer Interconnection Network  

E-Print Network (OSTI)

All optical path interconnection networks employing dense wavelength division multiplexing can provide vast improvements in supercomputer performance. However, the lack of efficient optical buffering requires investigation of new topologies and routing techniques. This paper introduces and evaluates the Data Vortex optical switching architecture which uses cylindrical routing paths as a packet buffering alternative. In addition, the impact of the number of angles on the overall network performance is studied through simulation. Using optimal topology configurations, the Data Vortex is compared to two existing switching architectures—butterfly and omega networks. The three networks are compared in terms of throughput, accepted traffic ratio, and average packet latency. The Data Vortex is shown to exhibit comparable latency and a higher acceptance rate (2x at 50 percent load) than the butterfly and omega topologies.

Cory Hawkins; Benjamin A. Small; D. Scott Wills; Keren Bergman

2007-01-01T23:59:59.000Z

137

Identification of vortexes obstructing the dynamo mechanism in laboratory experiments  

E-Print Network (OSTI)

The magnetohydrodynamic dynamo effect explains the generation of self-sustained magnetic fields in electrically conducting flows, especially in geo- and astrophysical environments. Yet the details of this mechanism are still unknown, e.g., how and to which extent the geometry, the fluid topology, the forcing mechanism and the turbulence can have a negative effect on this process. We report on numerical simulations carried out in spherical geometry, analyzing the predicted velocity flow with the so-called Singular Value Decomposition, a powerful technique that allows us to precisely identify vortexes in the flow which would be difficult to characterize with conventional spectral methods. We then quantify the contribution of these vortexes to the growth rate of the magnetic energy in the system. We identify an axisymmetric vortex, whose rotational direction changes periodically in time, and whose dynamics are decoupled from those of the large scale background flow, is detrimental for the dynamo effect. A compar...

Limone, Angelo; Forest, Cary B; Jenko, Frank

2013-01-01T23:59:59.000Z

138

Low Head, Vortex Induced Vibrations River Energy Converter  

DOE Green Energy (OSTI)

Vortex Induced Vibrations Aquatic Clean Energy (VIVACE) is a novel, demonstrated approach to extracting energy from water currents. This invention is based on a phenomenon called Vortex Induced Vibrations (VIV), which was first observed by Leonardo da Vinci in 1504AD. He called it ‘Aeolian Tones.’ For decades, engineers have attempted to prevent this type of vibration from damaging structures, such as offshore platforms, nuclear fuel rods, cables, buildings, and bridges. The underlying concept of the VIVACE Converter is the following: Strengthen rather than spoil vortex shedding; enhance rather than suppress VIV; harness rather than mitigate VIV energy. By maximizing and utilizing this unique phenomenon, VIVACE takes this “problem” and successfully transforms it into a valuable resource for mankind.

Bernitsas, Michael B.; Dritz, Tad

2006-06-30T23:59:59.000Z

139

Shock-compressible-vortex interactions: Computing approximate post-shock fields  

E-Print Network (OSTI)

Shock-compressible-vortex interactions: Computing approximate post-shock fields G.K. O'Reilly and D of the passage of a planar shock through a steady compressible vortex is developed. To compute the approximate post-shock fields, the steady pre-shock vortex is decomposed into a sum of frozen sinusoidal modes

Barr, Al

140

Non-Contact Haptic Feedback Using Air Vortex Rings Sidhant Gupta1,2  

E-Print Network (OSTI)

regions of the human body. Author Keywords Non-contact haptic feedback; air vortex rings ACM1 AirWave: Non-Contact Haptic Feedback Using Air Vortex Rings Sidhant Gupta1,2 , Dan Morris1 feedback into such interaction. In this work, we explore the use of air vortex rings for this purpose

Rajamani, Sriram K.

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they are not comprehensive nor are they the most current set.
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141

Wigner function and entanglement of generalized quantum optical vortex  

E-Print Network (OSTI)

We calculate the Wigner quasiprobability distribution function of the quantum elliptical vortex (QEV), produced by coupling squeezed coherent states of two modes . The coupling between the two modes is performed by using beam splitter (BS) or a dual channel directional coupler (DCDC). The quantum interference due to the coupling between the two modes promises the generation of controlled entanglement for quantum computation and quantum tomography. We calculate the entanglement of such generalized elliptical vortex formed by quantized radiation field (QEV), using Wigner quasiprobability distribution function for such states. We find a critical squeezing parameter above which the entanglement is less for higher vorticity, which is counter intuitive.

Bandyopadhyay, Abir; Singh, R P

2011-01-01T23:59:59.000Z

142

Reply to "Comment on 'Vortex-assisted photon counts and their magnetic field dependence in single-photon superconducting detectors'"  

SciTech Connect

The vortex crossing rate in thin current-biased superconducting strips, calculated within the London approach employing the concept of a vortex as a particle, is very sensitive to the cutoff at the vortex core size. To account properly for the vortex core, one needs to use microscopic theory.

Bulaevskii, L.N.; Graf, Matthias; Kogan, Vladimir G.

2012-07-16T23:59:59.000Z

143

On the Onset Vortex of the Summer Monsoon  

Science Conference Proceedings (OSTI)

In this paper we examine the evolution of the low-level flow over the Arabian Sea during the onset of the summer monsoon. A detailed examination of the onset vortex that forms over the Arabian Sea just prior to the commencement of heavy rains ...

T. N. Krishnamurti; Philip Ardanuy; Y. Ramanathan; Richard Pasch

1981-02-01T23:59:59.000Z

144

Blade-Vortex Interactions in High Pressure Steam Turbines  

E-Print Network (OSTI)

A detailed experimental and numerical investigation of the transport of streamwise (passage) vortices in high-pressure axial turbines and their interaction with the downstream blade rows was performed. The results indicate large variations in the downstream flow field, notably the development of the secondary flows. The mechanism of passage vortex transport was studied in two differently configured high-pressure turbine stages. In the first configuration, the blades are radially stacked while the second configuration features three-dimensionally stacked high-pressure steam turbine blading. The stator hub passage vortex is chopped by the downstream blade row in a similar way to the wake. The bowed vortex tube near the inlet to the rotor appeared to develop two counter-rotating legs extending back to the leading edges of the adjacent blades. These were termed the suction side leg and the pressure side leg. The two legs of the incoming passage vortex then convect with the respective velocities on the blade surfaces. The results are discussed for the radially stacked turbine and the 3-D turbine separately.

Venkata Siva Prasad Chaluvadi

2000-01-01T23:59:59.000Z

145

Nielsen-Olesen vortex in varying-alpha theories  

E-Print Network (OSTI)

We consider soliton solutions to Bekenstein's theory, for which the fine structure constant $\\alpha=e^2/(4\\pi\\hbar c)$ is allowed to vary due to the presence of a dielectric field pervading the vacuum. More specifically we investigate the effects of a varying $\\alpha$ upon a complex scalar field with a U(1) electromagnetic gauge symmetry subject to spontaneous symmetry breaking. We find vortex solutions to this theory, similar to the Nielsen-Olesen vortex. Near the vortex core the electric charge is typically much larger than far away from the string, lending these strings a superconducting flavour. In general the dielectric field coats the usual local string with a global string envelope. We discuss the cosmological implications of networks of such strings, with particular emphasis on their ability to generate inhomogeneous recombination scenarios. We also consider the possibility of the dielectric being a charged free field. Even though the vacuum of such a field is trivial, we find that the dielectric arranges itself in the shape of a local string, with a quantized magnetic flux at the core -- presumably borrowing these topological features from the underlying Nielsen-Olesen vortex.

J. Magueijo; H. Sandvik; T. W. B. Kibble

2001-01-15T23:59:59.000Z

146

Improving Building Comfort and Energy Savings of the McKenzie Airport Terminal by Maintaining and Improving Pneumatic Control Systems  

E-Print Network (OSTI)

McKenzie Airport Terminal is located at Easterwood Airport, which is owned and operated by Texas A&M University. It was built in 1988. Most all HVAC equipment, which includes boiler, chiller, pumps, AHUs and exhaust fans, due to lack of maintenance, had some form of deteriorated controls, components, and operational function. For example, most of pneumatic controls were failed due to bad components, wrong settings, and disconnection before the Continuous CommissioningR (CCSM). This caused humid and hot problems of the building, and wasted energy. After maintaining and improving the pneumatic controls, the boiler and hot water pump is now turned off when outside air temperature is higher than 80°F. The chiller is now shut off when the outside air temperature is below 55 °F, and the economizers activate to maintain discharge air temperature when the outside air temperature is below 60 °F. The building comfort in temperature and relative humidity (RH) is improved after CCSM. For example, average space temperature of the building was above 75 °F most of the time before CCSM and is now 73 °F after CCSM. The relative humidity in the baggage claim area was 70% before CCSM and is now 55% after CCSM. The annual savings of electricity for chiller and natural gas for boiler are $5,040 and $12,090 respectively. The total annual energy savings are $17,130.

Liu, C.; Bruner, H. L.; Deng, S.; Brundidge, T.; Turner, W. D.; Claridge, D. E.

2004-01-01T23:59:59.000Z

147

Membrane stabilizer  

DOE Patents (OSTI)

A device is provided for stabilizing a flexible membrane secured within a frame, wherein a plurality of elongated arms are disposed radially from a central hub which penetrates the membrane, said arms imposing alternately against opposite sides of the membrane, thus warping and tensioning the membrane into a condition of improved stability. The membrane may be an opaque or translucent sheet or other material. 10 figs.

Mingenbach, W.A.

1988-02-09T23:59:59.000Z

148

Hairpin vortex formation, a case study for unsteady visualization.  

SciTech Connect

To better understand the vortex dynamics of coherent structures in turbulent and transitional boundary layers, we consider direct numerical simulation of the interaction between a flat-plateboundary-layer flow and an isolated hemispherical roughness element. Of principal interest is the evolution of hairpin vortices that form an interlacing pattern in the wake of the hemisphere, lift away from the wall, and are stretched by the shearing action of the boundary layer. Using animations of unsteady three-dimensional representations of this flow, produced by the vtk toolkit and enhanced to operate in a CAVE virtual environment, we identify and study several key features in the evolution of this complex vortex topology not previously observed in other visualization formats.

Fischer, P. F.; Papka, M. E.; Szymanski, M.; Tufo, H. M.

1999-08-10T23:59:59.000Z

149

MHK Technologies/Vortex Oscillation | Open Energy Information  

Open Energy Info (EERE)

Oscillation Oscillation < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Vortex Oscillation.jpg Technology Profile Primary Organization Vortex Oscillation Technology Ltd Technology Resource Click here Current Technology Type Click here Attenuator Technology Readiness Level Click here TRL 1 3 Discovery Concept Def Early Stage Dev Design Engineering Technology Description If cylinder or another body is fixed on a moving bonding this force can set the body or its separate parts into oscillation e g elastic slat If the system of mechanical energy output is organized correctly this device can be considered as generator Technology Dimensions Device Testing Date Submitted 08:12.7 << Return to the MHK database homepage Retrieved from

150

Spin Stability  

NLE Websites -- All DOE Office Websites (Extended Search)

Stability Stability of Asymmetrically Charged Plasma Dust I. H. Hutchinson Plasma Science and Fusion Center Massachusetts Institute of Technology, Cambridge, MA, USA Recently it has been reported that, under some circumstances, dust particles sus- pended in the sheath edge are observed to spin [1, 2, 3]. The present paper shows that there is a natural electrostatic mechanism that should cause even perfectly spherical par- ticles in a perfectly irrotational, magnetic-field-free flowing plasma to spin. The stability criterion and the final spin state are obtained[4]. When the particle is made of an insulating material, it can support potential dif- ferences around its surface. In the limit of zero conductivity, and ignoring all charging effects other than electron or ion collection, the surface charge density accumulates in such a way as to bring the local electric current density to zero.

151

Observable Vortex Properties in Finite Temperature Bose Gases  

E-Print Network (OSTI)

We study the dynamics of vortices in finite temperature atomic Bose-Einstein condensates, focussing on decay rates, precession frequencies and core brightness, motivated by a recent experiment (Freilich et al. Science 329, 1182 (2010)) in which real-time dynamics of a single vortex was observed. Using the ZNG formalism based on a dissipative Gross-Pitaevskii equation for the condensate coupled to a semi-classical Boltzmann equation for the thermal cloud, we find a rapid nonlinear increase of both the decay rate and precession frequency with increasing temperatures. The increase, which is dominated by the dynamical condensate-thermal coupling is also dependent on the intrinsic thermal cloud collisional dynamics; the precession frequency also varies with the initial radial coordinate. The integrated thermal cloud density in the vortex core is for the most part independent of the position of the vortex (except when it is near the condensate edge) with its value increasing with temperature. This could potentially be used as a variant to the method of Coddington et al. (Phys. Rev. A 70, 063607 (2004)) for experimentally determining the temperature.

A. J. Allen; E. Zaremba; C. F. Barenghi; N. P. Proukakis

2012-10-30T23:59:59.000Z

152

Annihilation of vortex dipole in an Oblate Bose-Einstein Condensate  

E-Print Network (OSTI)

We theoretically explore the annihilation of vortex dipole, generated when an obstacle moves through a condensate, in an oblate Bose-Einstein Condensate and the possible reasons for the annihilation. We show that the grey soliton, which results from vortex dipole annihilation, is lower in energy than the vortex dipole. We also investigate the annihilation events numerically and observe annihilation occurs only when the vortex dipole overtake the obstacle. Further more, we find that the adding noise reduces the probability of annihilation events. This may explain the lack of annihilation events in experimental realizations.

Prabhakar, Shashi; Gautam, S; Angom, D

2013-01-01T23:59:59.000Z

153

Vortex formation of a Bose-Einstein condensate in a rotating deep optical lattice  

Science Conference Proceedings (OSTI)

We study the dynamics of vortex nucleation and lattice formation in a Bose-Einstein condensate in a rotating square optical lattice by numerical simulations of the Gross-Pitaevskii equation. Different dynamical regimes of vortex nucleation are found, depending on the depth and period of the optical lattice. We make an extensive comparison with the experiments by R. A. Williams et al.[Phys. Rev. Lett. 104, 050404 (2010)], especially focusing on the issues of the critical rotation frequency for the first vortex nucleation and the vortex number as a function of rotation frequency.

Kato, Akira; Nakano, Yuki; Kasamatsu, Kenichi; Matsui, Tetsuo [Department of Physics, Kinki University, Higashi-Osaka, Osaka 577-8502 (Japan)

2011-11-15T23:59:59.000Z

154

Numerical Simulation of Flame-Vortex Interactions in Natural and Synthetic Gas Mixtures .  

E-Print Network (OSTI)

??The interactions between laminar premixed flames and counter-rotating vortex pairs in natural and synthetic gas mixtures have been computationally investigated through the use of Direct… (more)

Weiler, Justin D.

2004-01-01T23:59:59.000Z

155

Stability of spiral wave vortex filaments with phase twists Keeyeol Nam,* Edward Ott,  

E-Print Network (OSTI)

. Guzdar, and Michael Gabbay Institute for Plasma Research, University of Maryland, College Park, Maryland

Rubloff, Gary W.

156

Langmuir probe diagnostics of an atmospheric pressure, vortex-stabilized nitrogen plasma jet  

SciTech Connect

Langmuir probe measurements in an atmospheric pressure direct current (dc) plasma jet are reported. Sweeping probes were used. The experiment was carried out using a dc non-transferred arc torch with a rod-type cathode and an anode of 5 mm diameter. The torch was operated at a nominal power level of 15 kW with a nitrogen flow rate of 25 Nl min{sup -1}. A flat ion saturation region was found in the current-voltage curve of the probe. The ion saturation current to a cylindrical probe in a high-pressure non local thermal equilibrium (LTE) plasma was modeled. Thermal effects and ionization/recombination processes inside the probe perturbed region were taken into account. Averaged radial profiles of the electron and heavy particle temperatures as well as the electron density were obtained. An electron temperature around 11 000 K, a heavy particle temperature around 9500 K and an electron density of about 4 Multiplication-Sign 10{sup 22} m{sup -3}, were found at the jet centre at 3.5 mm downstream from the torch exit. Large deviations from kinetic equilibrium were found throughout the plasma jet. The electron and heavy particle temperature profiles showed good agreement with those reported in the literature by using spectroscopic techniques. It was also found that the temperature radial profile based on LTE was very close to that of the electrons. The calculations have shown that this method is particularly useful for studying spraying-type plasma jets characterized by electron temperatures in the range 9000-14 000 K.

Prevosto, L.; Mancinelli, B. R. [Grupo de Descargas Electricas, Departamento Ingenieria Electromecanica, Facultad Regional Venado Tuerto (UTN), Laprida 651, (2600) Venado Tuerto, Santa Fe (Argentina); Kelly, H. [Grupo de Descargas Electricas, Departamento Ingenieria Electromecanica, Facultad Regional Venado Tuerto (UTN), Laprida 651, (2600) Venado Tuerto, Santa Fe (Argentina) and Instituto de Fisica del Plasma (CONICET), Departamento de Fisica, Facultad de Ciencias Exactas y Naturales UBA Ciudad Universitaria Pab. I, (1428) Buenos Aires (Argentina)

2012-09-15T23:59:59.000Z

157

Description of Selected Algorithms and Implementation Details of a Concept-Demonstration Aircraft VOrtex Spacing System (AVOSS)  

Science Conference Proceedings (OSTI)

A ground-based system has been developed to demonstrate the feasibility of automating the process of collecting relevant weather data, predicting wake vortex behavior from a data base of aircraft, prescribing safe wake vortex spacing criteria, estimating ...

Hinton David A.

2001-06-01T23:59:59.000Z

158

Cloud-Resolving Simulations of Mesoscale Vortex Intensification and Its Effect on a Serial Mesoscale Convective System  

Science Conference Proceedings (OSTI)

The authors performed numerical simulations of the 27–28 May 1998 mesoscale convective vortex (MCV) and mesoscale convective system (MCS) to understand how the MCV modulated the convection, and how the convection intensified the vortex. The fifth-...

Christopher A. Davis; Stanley B. Trier

2002-12-01T23:59:59.000Z

159

Solution of linear problems of the uniform motion of a vortex source in a multilayer fluid  

Science Conference Proceedings (OSTI)

A method of solving linear problems of the uniform motion of a vortex source in a multilayer fluid having an arbitrary finite number of layers is proposed. As an example, the problem of the motion of a vortex source of given intensity in a three-layer fluid is solved. Formulas for the complex velocities and hydrodynamic reactions are obtained.

Gorlov, S.I.

1995-11-01T23:59:59.000Z

160

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

E-Print Network (OSTI)

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

Franz, Marcel

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

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

E-Print Network (OSTI)

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

Yang, Vigor

162

On a Graphics Hardware-Based Vortex Detection and Visualization System  

Science Conference Proceedings (OSTI)

We present a graphics hardware-based system for interactive denoising, vortex detection, and visualization of vector data. No intermediate results need to be read back by the application once the vector field has been loaded onto the graphics adapter. ... Keywords: Flow visualization, Graphics hardware, Vortex detection

S. Stegmaier; T. Ertl

2005-04-01T23:59:59.000Z

163

Polarization radiation of vortex electrons with large orbital angular momentum  

E-Print Network (OSTI)

Vortex electrons, - freely propagating electrons whose wavefunction has helical wavefronts, - could become a novel tool in the physics of electromagnetic radiation. They carry a non-zero intrinsic orbital angular momentum (OAM) $\\ell$ with respect to the propagation axis and, for \\ell \\gg 1, a large OAM-induced magnetic moment, \\mu ~ \\ell \\mu_B (\\mu_B is the Bohr magneton), which influences the radiation of electromagnetic waves. Here, we consider in detail the OAM-induced effects by such electrons in two forms of polarization radiation, namely in Cherenkov radiation and transition radiation. Thanks to the large \\ell, we can neglect quantum or spin-induced effects, which are of the order of \\hbar \\omega/E_e \\ll 1, but retain the magnetic moment contribution \\ell \\hbar \\omega/E_e \\lesssim 1, which makes the quasiclassical approach to polarization radiation applicable. We discuss the magnetic moment contribution to polarization radiation, which has never been experimentally observed, and study how its visibility depends on the kinematical parameters and the medium permittivity. In particular, it is shown that this contribution can, in principle, be detected in azimuthally non-symmetrical problems, for example when vortex electrons obliquely cross a metallic screen (transition radiation) or move nearby it (diffraction radiation). We predict a left-right angular asymmetry of the transition radiation (in the plane where the charge radiation distributions would stay symmetric), which appears due to an effective interference between the charge radiation field and the magnetic moment one. Numerical values of this asymmetry for vortex electrons with E_e = 300keV and \\ell = O(100-1000) are O(0.1-1%), and we argue that this effect could be detected with existing technology. The finite conductivity of the target and frequency dispersion play the crucial roles in these predictions.

Igor P. Ivanov; Dmitry V. Karlovets

2013-05-28T23:59:59.000Z

164

Wigner distribution function and entanglement of generalized quantum optical vortex  

E-Print Network (OSTI)

We calculate the Wigner (quasi)probability distribution function of the quantum optical elliptical vortex (QEV), generated by coupling squeezed vacuum states of two modes. The coupling between the two modes is performed by using beam splitter (BS) or a dual channel directional coupler (DCDC). The quantum interference due to the coupling between the two modes promises the generation of controlled entanglement for quantum computation and quantum tomography. We compute the entanglement of such QEV formed by non-classical radiation field, using Wigner function. We report a critical squeezing parameter above which the entanglement is less for higher vorticity, which is counter intuitive.

Abir Bandyopadhyay; Shashi Prabhakar; R. P. Singh

2011-01-25T23:59:59.000Z

165

Vortex nozzle for segmenting and transporting metal chips from turning operations  

DOE Patents (OSTI)

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

Bieg, L.F.

1993-04-20T23:59:59.000Z

166

Vortex nozzle for segmenting and transporting metal chips from turning operations  

DOE Patents (OSTI)

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

Bieg, L.F.

1992-12-31T23:59:59.000Z

167

Development of a multi-functional scarifier dislodger with an integral pneumatic conveyance retrieval system for single-shell tank remediation. FY93 summary report  

SciTech Connect

The Underground Storage Tank Integrated Demonstration (UST-ID) is evaluating several hydraulic dislodger concepts and retrieval technologies to develop specifications for system that can retrieve wastes from single-shell tanks. Each of the dislodgers will be evaluated sequentially to determine its ability to fracture and dislodge various waste simulants such as salt cake, sludge, and viscous liquid. The retrieval methods will be evaluated to determine their ability to convey this dislodged material from the tank. This report describes on-going research that commenced in FY93 to develop specifications for a scarifier dislodger coupled with a pneumatic conveyance retrieval system. The scarifier development is described in Section 3; pneumatic conveyance development is described in Section 4. Preliminary system specifications are listed in Section 5. FY94 plans are summarized in Section 6.

Bamberger, J.A.; McKinnon, M.A. [Pacific Northwest Lab., Richland, WA (United States); Alberts, D.A.; Steele, D.E. [Quest Integrated, Inc., Kent, WA (United States); Crowe, C.T. [Washington State Univ., Pullman, WA (United States)

1994-10-01T23:59:59.000Z

168

Further development of the pneumatic method to harness hydropower and its experimental implementation in the State of Maine. Final report, [February 15, 1990--February 14, 1993  

DOE Green Energy (OSTI)

This report contains conclusive results of the research project entitled ``Further Development of the Pneumatic Method to Harness Hydropower and its Experimental Implementation in the State of Maine`` sponsored by the US Department of Energy (Contract DE-FG02-91ER12113). The results obtained by this research are considerably beyond the original goals anticipated by the contract which were a theoretical study of the method only and its possible applications. In fact, the success of the analytical research program has allowed us to move on to development, construction and testing of a physical model of the hydro-air power converter and, subsequently, to development of a well equipped hydro-pneumatic power laboratory at Northeastern University. Photographs la and 2a show both the laboratory and the model. Good performance of the model proves that the hydro-pneumatic concept holds much promise for development of an ecologically safe and commercially attractive novel approach to harnessing ultra low-head hydropower. As a result, private companies have started to support this new technology, and to invest money in its further development and construction of demonstration power plants (Appendix 1). Visitors at the Northeastern University laboratory often praise this new technique, as is attested by the articles in the Wall Street Journal (Appendix 2) and the Technology Review (Appendix 3).

Gorlov, A.M.

1994-03-01T23:59:59.000Z

169

Heat Transfer Enhancement in Separated and Vortex Flows  

SciTech Connect

This document summarizes the research performance done at the Heat Transfer Laboratory of the University of Minnesota on heat transfer and energy separation in separated and vortex flow supported by DOE in the period September 1, 1998--August 31, 2003. Unsteady and complicated flow structures in separated or vortex flows are the main reason for a poor understanding of heat transfer under such conditions. The research from the University of Minnesota focused on the following important aspects of understanding such flows: (1) Heat/mass transfer from a circular cylinder; (2) study of energy separation and heat transfer in free jet flows and shear layers; and (3) study of energy separation on the surface and in the wake of a cylinder in crossflow. The current study used three different experimental setups to accomplish these goals. A wind tunnel and a liquid tunnel using water and mixtures of ethylene glycol and water, is used for the study of prandtl number effect with uniform heat flux from the circular cylinder. A high velocity air jet is used to study energy separation in free jets. A high speed wind tunnel, same as used for the first part, is utilized for energy separation effects on the surface and in the wake of the circular cylinder. The final outcome of this study is a substantial advancement in this research area.

Richard J. Goldstein

2004-05-27T23:59:59.000Z

170

Dissipative dynamics of vortex arrays in trapped Bose-condensed gases: neutron stars physics on $?$K scale  

E-Print Network (OSTI)

We develop a theory of dissipative dynamics of large vortex arrays in trapped Bose-condensed gases. We show that in a static trap the interaction of the vortex array with thermal excitations leads to a non-exponential decay of the vortex structure, and the characteristic lifetime depends on the initial density of vortices. Drawing an analogy with physics of pulsar glitches, we propose an experiment which employs the heating of the thermal cloud in the course of the decay of the vortex array as a tool for a non-destructive study of the vortex dynamics.

P. O. Fedichev; A. E. Muryshev

2000-04-17T23:59:59.000Z

171

STABILIZED OSCILLATOR  

DOE Patents (OSTI)

This patent relates to sine-wave generators and in particular describes a generator with a novel feedback circuit resulting in improved frequency stability. The generator comprises two triodes having a common cathode circuit connected to oscillate at a frequency and amplitude at which the loop galn of the circutt ls unity, and another pair of triodes having a common cathode circuit arranged as a conventional amplifier. A signal is conducted from the osciliator through a frequency selective network to the amplifier and fed back to the osciliator. The unique feature of the feedback circuit is the amplifier operates in the nonlinear portion of its tube characteristics thereby providing a relatively constant feedback voltage to the oscillator irrespective of the amplitude of its input signal.

Jessen, P.L.; Price, H.J.

1958-03-18T23:59:59.000Z

172

Observation of coupled vortex gyrations by 70-ps-time and 20-nm-space- resolved full-field magnetic transmission soft x-ray microscopy  

SciTech Connect

We employed time-and space-resolved full-field magnetic transmission soft x-ray microscopy to observe vortex-core gyrations in a pair of dipolar-coupled vortex-state Permalloy (Ni{sub 80}Fe{sub 20}) disks. The 70 ps temporal and 20 nm spatial resolution of the microscope enabled us to simultaneously measure vortex gyrations in both disks and to resolve the phases and amplitudes of both vortex-core positions. We observed their correlation for a specific vortex-state configuration. This work provides a robust and direct method of studying vortex gyrations in dipolar-coupled vortex oscillators.

Jung, Hyunsung; Yu, Young-Sang; Lee, Ki-Suk; Im, Mi-Young; Fischer, Peter; Bocklage, Lars; Vogel, Andreas; Bolte, Markus; Meier, Guido; Kim, Sang-Koog

2010-09-01T23:59:59.000Z

173

An adaptive mesh method for the simulation of Blade Vortex Interaction  

E-Print Network (OSTI)

An adaptive mesh method for the simulation of parallel ics. Blade Vortex Interaction (BV1) with an active Trailing Edge Flap (TEF) is presented. The two-dimensional 1111-steady problem is solved by a higher order upwind Euler method for an unstructured mesh. A local mesh adaptation technique is employed to maintain vortex strength by capturing the details of the convecting vortex. The computational technique does not require any assumption on the vortex structure, and, therefore is suitable for close interaction of the vortex and the blade. The adaptive method is based on cell subdivisions and allows for frequent mesh adaptation due to its fast speed. To demonstrate the reduction of numerical dissipation of a vortex via mesh adaptation, we first consider a simple case with a convecting vortex in freestream. Finally, we apply tile techniques to examine the effectiveness of an active TEF on BVI in reducing the pressure perturbations at the airfoil leading edge. For the boundary motion due to TEF deployment, a local recessing procedure is utilized to maintain mesh quality by avoiding distorted mesh elements near the flap.

Kim, Kyu-Sup

1998-01-01T23:59:59.000Z

174

Axial dipolar dynamo action in the Taylor-Green vortex  

E-Print Network (OSTI)

We present a numerical study of the magnetic field generated by the Taylor-Green vortex. We show that periodic boundary conditions can be used to mimic realistic boundary conditions by prescribing the symmetries of the velocity and magnetic fields. This gives insight in some problems of central interest for dynamos: the possible effect of velocity fluctuations on the dynamo threshold, the role of boundary conditions on the threshold and on the geometry of the magnetic field generated by dynamo action. In particular, we show that an axial dipolar dynamo similar to the one observed in a recent experiment can be obtained with an appropriate choice of the symmetries of the magnetic field. The nonlinear saturation is studied and a simple model explaining the magnetic Prandtl number dependence of the super/sub critical nature of the dynamo transition is given.

Giorgio Krstulovic; Gentien Thorner; Julien-Piera Vest; Stephan Fauve; Marc Brachet

2011-09-19T23:59:59.000Z

175

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

E-Print Network (OSTI)

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

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

2012-09-16T23:59:59.000Z

176

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

E-Print Network (OSTI)

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

Tsoy, L A; Komarov, A G; Tsoy, A N

2012-01-01T23:59:59.000Z

177

Energy harvesting using vortex-induced vibrations of tensioned cables  

E-Print Network (OSTI)

The development of energy harvesting systems based on fluid/structure interactions is part of the global search for innovative tools to produce renewable energy. In this paper, the possibility to harvest energy from a flow using vortex-induced vibrations (VIV) of a tensioned flexible cable is analyzed. The fluid loading on the vibrating solid and resulting dynamics are computed using an appropriate wake-oscillator model, allowing one to perform a systematic parametric study of the efficiency. The generic case of an elastically-mounted rigid cylinder is first investigated, before considering an infinite cable with two different types of energy harvesting : a uniformly spanwise distributed harvesting and then a periodic distribution of discrete harvesting devices. The maximum harvesting efficiency is of the same order for each configuration and is always reached when the solid body and its wake are in a frequency lock-in state.

Grouthier, Clement; de Langre, Emmanuel

2012-01-01T23:59:59.000Z

178

Composite stabilizer unit  

DOE Patents (OSTI)

This invention is comprised of an improved fin stabilized projectile including multiple stabilizer fins upon a stabilizer unit situated at the aft end of the projectile is provided, the improvement wherein the stabilizer fins are joined into the stabilizer unit by an injection molded engineering grade polymer.

Ebaugh, L.R.; Sadler, C.P.; Carter, G.D.

1990-12-31T23:59:59.000Z

179

Composite stabilizer unit  

DOE Patents (OSTI)

This invention is comprised of an improved fin stabilized projectile including multiple stabilizer fins upon a stabilizer unit situated at the aft end of the projectile is provided, the improvement wherein the stabilizer fins are joined into the stabilizer unit by an injection molded engineering grade polymer.

Ebaugh, L.R.; Sadler, C.P.; Carter, G.D.

1990-01-01T23:59:59.000Z

180

Composite stabilizer unit  

SciTech Connect

An improved fin stabilized projectile including multiple stabilizer fins upon a stabilizer unit situated at the aft end of the projectile is provided, the improvement wherein the stabilizer fins are joined into the stabillizer unit by an injection molded engineering grade polymer.

Ebaugh, Larry R. (Los Alamos, NM); Sadler, Collin P. (Los Alamos, NM); Carter, Gary D. (Espanola, NM)

1992-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

The Kinematics of a Midlatitude, Continental Mesoscale Convective System and Its Mesoscale Vortex  

Science Conference Proceedings (OSTI)

The authors present a unique, scale-discriminating study of the environment-relative circulations within a mesoscale convective system (MCS) and mesoscale convective vortex (MCV). The MCS, a leading convective line and trailing stratiform region ...

Jason C. Knievel; Richard H. Johnson

2002-07-01T23:59:59.000Z

182

Wave–Current Interaction: A Comparison of Radiation-Stress and Vortex-Force Representations  

Science Conference Proceedings (OSTI)

The vortex-force representation of the wave-averaged effects on currents is compared to the radiation-stress representation in a scaling regime appropriate to coastal and shelf waters. Three-dimensional and vertically integrated expressions for ...

E. M. Lane; J. M. Restrepo; J. C. McWilliams

2007-05-01T23:59:59.000Z

183

Evidence against an Antarctic Stratospheric Vortex Split during the Periods of Pre-IGY Temperature Measurements  

Science Conference Proceedings (OSTI)

Historic upper-air observations from Antarctica are inspected to investigate the uniqueness of the vortex split in the Antarctic spring of 2002. No comprehensive meteorological observations are available prior to the International Geophysical ...

Barbara Naujokat; Howard K. Roscoe

2005-03-01T23:59:59.000Z

184

Midtropospheric Anticyclonic Vortex Street Associated with a Cloud Band near a Cold Front  

Science Conference Proceedings (OSTI)

The characteristics and formation mechanism of an anticyclonic vortex street of meso-? scale, which appeared near a cold front around the Ryukyu Islands, Japan, on 11 April 1995, were examined by an analysis of observational data, a numerical ...

Eizi Toyoda; Hiroshi Niino; Kazuhisa Tsuboki; Ryuji Kimura; Masanori Yoshizaki

1999-08-01T23:59:59.000Z

185

Vortex Ring Dyons of the SU(2) Yang-Mills-Higgs Model  

Science Conference Proceedings (OSTI)

We present an axially symmetric vortex ring dyons solutions of the SU(2) Yang-Mills-Higgs theory. These vortex rings carry electric charges that are determined by a parameter, -1{<=}{eta}{<=}1. They possess vanishing magnetic charge and are located at a ring centered around the z-axis where the Higgs field vanishes. These stationary vortex ring dyon solutions possess finite energy but they do not satisfy the first order Bogomol'nyi equations. In the Bogomol'nyi-Prasad-Sommerfield (BPS) limit where the Higgs field potential is zero, the time component of the gauge field is parallel to the Higgs field in isospace. The total energy, net electric charge and diameter of the vortex ring increase exponentially to infinity when {eta} approaches {+-}1. On the contrary, when {lambda} = 1, all these three values reach their critical value as {eta} approaches {+-}1.

Lim, Kok-Geng; Teh, Rosy; Wong, Khai-Ming [School of Physics, Universiti Sains Malaysia 11800 USM Penang (Malaysia)

2011-03-30T23:59:59.000Z

186

The Splitting of the Stratospheric Polar Vortex in the Southern Hemisphere, September 2002: Dynamical Evolution  

Science Conference Proceedings (OSTI)

The polar vortex of the Southern Hemisphere (SH) split dramatically during September 2002. The large-scale dynamical effects were manifest throughout the stratosphere and upper troposphere, corresponding to two distinct cyclonic centers in the ...

Andrew J. Charlton; Alan O’Neill; William A. Lahoz; Paul Berrisford

2005-03-01T23:59:59.000Z

187

Ensemble Forecasting of Tropical Cyclone Motion Using a Barotropic Model. Part II: Perturbations of the Vortex  

Science Conference Proceedings (OSTI)

In Part I of this study, the technique of ensemble forecasting is applied to the problem of tropical cyclone motion prediction by perturbing the environmental flow. In this part, the focus is shifted to perturbation of the vortex structure. The ...

Kevin K. W. Cheung; Johnny C. L. Chan

1999-11-01T23:59:59.000Z

188

Jovian Dynamics. Part II: The Genesis and Equilibration of Vortex Sets  

Science Conference Proceedings (OSTI)

To extend studies of the dynamics of thin atmospheric layers, the generation and equilibration of multiple anticyclonic vortex sets associated with long solitary baroclinic Rossby waves are examined numerically using a primitive equation model ...

G. P. Williams

2002-04-01T23:59:59.000Z

189

Structure of a Midtropospheric Vortex Induced by a Mesoscale Convective System  

Science Conference Proceedings (OSTI)

On 9 June 1988 a mesoscale (200-km diameter) convectively generated vortex (MCV) passed through the Colorado wind-profiling network. The generating convective system, which was too small to meet Maddox’s mesoscale convective complex criteria, ...

Diana L. Bartels; John M. Brown; Edward I. Tollerud

1997-02-01T23:59:59.000Z

190

A Vortex-Based Perspective of Eastern Pacific Tropical Cyclone Formation  

Science Conference Proceedings (OSTI)

Tropical cyclone formation over the eastern Pacific during 2005 and 2006 was examined using primarily global operational analyses from the National Centers for Environmental Prediction. This paper represents a “vortex view” of genesis, adding to ...

Christopher Davis; Chris Snyder; Anthony C. Didlake Jr.

2008-07-01T23:59:59.000Z

191

Observations of a Storm Containing Misocyclones, Downbursts, and Horizontal Vortex Circulations  

Science Conference Proceedings (OSTI)

On 30 June 1982, a multicellular storm in Colorado produced four downbursts, three misocyclones, a miso-anticyclone, and horizontal vortex circulations within a relatively small area of the storm. Weather events associated with this storm ...

Cathy J. Kessinger; David B. Parsons; James W. Wilson

1988-10-01T23:59:59.000Z

192

The Role of Vortex and Environment Errors in Genesis Forecasts of Hurricanes Danielle and Karl (2010)  

Science Conference Proceedings (OSTI)

An ensemble of Weather Research and Forecasting Model (WRF) forecasts initialized from a cycling ensemble Kalman filter (EnKF) system is used to evaluate the sensitivity of Hurricanes Danielle and Karl’s (2010) genesis forecasts to vortex and ...

Ryan D. Torn; David Cook

2013-01-01T23:59:59.000Z

193

An Analytic Vortex Initialization Technique for Idealized Tropical Cyclone Studies in AGCMs  

Science Conference Proceedings (OSTI)

The paper discusses the design of idealized tropical cyclone experiments in atmospheric general circulation models (AGCMs). The evolution of an initially weak, warm-core vortex is investigated over a 10-day period with varying initial conditions ...

Kevin A. Reed; Christiane Jablonowski

2011-02-01T23:59:59.000Z

194

The Garden City, Kansas, Storm during VORTEX 95. Part II: The Wall Cloud and Tornado  

Science Conference Proceedings (OSTI)

On 16 May 1995, a supercell storm produced an F1 tornado near Garden City, Kansas, during VORTEX (Verification of the Origins of Rotation in Tornadoes Experiment). This event provided the first opportunity to synthesize data collected by a new ...

Roger M. Wakimoto; Chinghwang Liu

1998-02-01T23:59:59.000Z

195

The Effect of Tropospheric Jet Latitude on Coupling between the Stratospheric Polar Vortex and the Troposphere  

Science Conference Proceedings (OSTI)

A dry general circulation model is used to investigate how coupling between the stratospheric polar vortex and the extratropical tropospheric circulation depends on the latitude of the tropospheric jet. The tropospheric response to an identical ...

Chaim I. Garfinkel; Darryn W. Waugh; Edwin P. Gerber

2013-03-01T23:59:59.000Z

196

The Role of Multiple Vortex Tornado Structure in Causing Storm Researcher Fatalities  

Science Conference Proceedings (OSTI)

A large and violent tornado/multiple vortex mesocyclone (MVMC) / tornado tracked east and northeastward near El Reno, Oklahoma on 31-May-2013, causing eight fatalities, including storm-chasers/researchers attempting to deploy in-situ instrumentation. Sub-...

Joshua Wurman; Karen Kosiba; Paul Robinson; Tim Marshall

197

A Concentrated Outbreak of Tornadoes, Downbursts and Microbursts, and Implications Regarding Vortex Classification  

Science Conference Proceedings (OSTI)

A remarkable case of severe weather occurred near Springfield, Illinois on 6 August 1977. Aerial and ground surveys revealed that 17 cyclonic vortices an anticyclonic vortex, 10 downbursts and 19 microbursts occurred in a limited (20 km × 40 km) ...

Gregory S. Forbes; Roger M. Wakimoto

1983-01-01T23:59:59.000Z

198

Mesoscale Convective Vortex Formation in a Weakly Sheared Moist Neutral Environment  

Science Conference Proceedings (OSTI)

Idealized simulations of a diabatic Rossby vortex (DRV) in an initially moist neutral baroclinic environment are performed using the fifth-generation National Center for Atmospheric Research–Pennsylvania State University (NCAR–PSU) Mesoscale ...

Robert J. Conzemius; Richard W. Moore; Michael T. Montgomery; Christopher A. Davis

2007-05-01T23:59:59.000Z

199

Intense Vortex Motion on the Beta Plane: Development of the Beta Gyres  

Science Conference Proceedings (OSTI)

An analytical theory is presented for the self-induced translation of an intense vortex relative to a uniform background flow on the ? plane. The equivalent barotropic approximation is used to formulate the initial value problem within a polar ...

Georgi G. Sutyrin; Glenn R. Flierl

1994-03-01T23:59:59.000Z

200

Interaction of a Baroclinic Vortex with Background Shear: Application to Hurricane Movement  

Science Conference Proceedings (OSTI)

Most extant studies of tropical cyclone movement consider a barotropic vortex on a ? plane. However, observations have shown that real tropical cyclones are strongly baroclinic, with broad anticyclones aloft. Also, the distribution of the large-...

Chun-Chieh Wu; Kerry A. Emanuel

1993-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

The Uses and Limitations of Contour Advection as a Technique for Examining Arctic Vortex Dynamics  

Science Conference Proceedings (OSTI)

A contour advection technique, contour advection with surgery (CAS), is applied to the Northern Hemisphere Arctic vortex during several dynamically active periods in midwinter and at several different levels in the stratosphere. The ability of ...

Michael N. Baker; Derek M. Cunnold

2001-08-01T23:59:59.000Z

202

Verification of RUC 0–1-h Forecasts and SPC Mesoscale Analyses Using VORTEX2 Soundings  

Science Conference Proceedings (OSTI)

This study uses radiosonde observations obtained during the second phase of the Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) to verify base-state variables and severe-weather-related parameters calculated from Rapid ...

Michael C. Coniglio

2012-06-01T23:59:59.000Z

203

The Gradient Genesis of Stratospheric Trace Species in the Subtropics and around the Polar Vortex  

Science Conference Proceedings (OSTI)

Mechanisms that control the formation and decay of meridional gradients in stratospheric trace species in the subtropics and around the polar vortex are investigated using a gradient genesis equation that uses mass-weighted isentropic zonal ...

Kazuyuki Miyazaki; Toshiki Iwasaki

2008-02-01T23:59:59.000Z

204

A Mesoscale Vortex Couplet Observed in the Trailing Anvil of a Multicellular Convective Complex  

Science Conference Proceedings (OSTI)

Observations collected during the Oklahoma–Kansas PRE-STORM experiment are used to document the evolution and structure of a mesoscale vortex couplet that developed in the mesoscale convective system that occurred on 16–17 June 1985. The ...

Johannes Verlinde; William R. Cotton

1990-05-01T23:59:59.000Z

205

Parametric Representation of the Primary Hurricane Vortex. Part II: A New Family of Sectionally Continuous Profiles  

Science Conference Proceedings (OSTI)

For applications such as windstorm underwriting or storm-surge forecasting, hurricane wind profiles are often approximated by continuous functions that are zero at the vortex center, increase to a maximum in the eyewall, and then decrease ...

H. E. Willoughby; R. W. R. Darling; M. E. Rahn

2006-04-01T23:59:59.000Z

206

Influence of Balanced Motions on Heavy Precipitation within a Long-Lived Convectively Generated Vortex  

Science Conference Proceedings (OSTI)

The forcing of heavy precipitation within a long-lived convectively generated mesoscale vortex (MCV) is investigated with the aid of diagnoses from Rapid Update Cycle gridded analyses. Organized convection within the MCV followed a distinct ...

Stanley B. Trier; Christopher A. Davis

2002-04-01T23:59:59.000Z

207

Source of Gravity Waves within a Vortex-Dipole Jet Revealed by a Linear Model  

Science Conference Proceedings (OSTI)

This study develops a linear numerical model to address the source mechanism of the gravity waves generated within a vortex dipole simulated in a fully nonlinear nonhydrostatic mesoscale model. The background flow for this linear model is ...

Shuguang Wang; Fuqing Zhang

2010-05-01T23:59:59.000Z

208

Submonthly Polar Vortex Variability and Stratosphere–Troposphere Coupling in the Arctic  

Science Conference Proceedings (OSTI)

A principal component analysis is performed to characterize intraseasonal variability in the boreal stratospheric polar vortex. In contrast to previous studies, the current analysis examines daily zonal-mean variability within a limited spatial ...

Robert X. Black; Brent A. McDaniel

2009-11-01T23:59:59.000Z

209

A New Parametric Model of Vortex Tangential-Wind Profiles: Development, Testing, and Verification  

Science Conference Proceedings (OSTI)

A new parametric model of vortex tangential-wind profiles is presented that is primarily designed to depict realistic-looking tangential wind profiles such as those in intense atmospheric vortices arising in dust devils, waterspouts, tornadoes, ...

Vincent T. Wood; Luther W. White

2011-05-01T23:59:59.000Z

210

Maximum Likelihood Estimates of Vortex Parameters from Simulated Coherent Doppler Lidar Data  

Science Conference Proceedings (OSTI)

The performance of pulsed coherent Doppler lidar in estimating aircraft trailing wake vortices by scanning across the aircraft flight track is evaluated using Monte Carlo lidar simulations of a simple vortex pair in both a nonturbulent and ...

Rod Frehlich; Robert Sharman

2005-02-01T23:59:59.000Z

211

An Observational Study of the Final Breakdown of the Southern Hemisphere Stratospheric Vortex in 2002  

Science Conference Proceedings (OSTI)

The 2002 Southern Hemisphere final warming occurred early, following an unusually active winter and the first recorded major warming in the Antarctic. The breakdown of the stratospheric polar vortex in October and November 2002 is examined using ...

Yvan J. Orsolini; Cora E. Randall; Gloria L. Manney; Douglas R. Allen

2005-03-01T23:59:59.000Z

212

A Subtropical Oceanic Mesoscale Convective Vortex Observed during SoWMEX/TiMREX  

Science Conference Proceedings (OSTI)

This study examines a subtropical oceanic mesoscale convective vortex (MCV) that occurred from 1800 UTC 4 June to 1200 UTC 6 June 2008 during intensive observing period (IOP) 6 of the Southwest Monsoon Experiment (SoWMEX) and the Terrain-...

Hsiao-Wei Lai; Christopher A. Davis; Ben Jong-Dao Jou

2011-08-01T23:59:59.000Z

213

Enhancement of vortex induced forces and motion through surface roughness control  

SciTech Connect

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

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

2011-11-01T23:59:59.000Z

214

Vortex Lattice Structures of a Bose-Einstein Condensate in a Rotating Lattice Potential  

E-Print Network (OSTI)

We study vortex lattice structures of a trapped Bose-Einstein condensate in a rotating lattice potential by numerically solving the time-dependent Gross-Pitaevskii equation. By rotating the lattice potential, we observe the transition from the Abrikosov vortex lattice to the pinned lattice. We investigate the transition of the vortex lattice structure by changing conditions such as angular velocity, intensity, and lattice constant of the rotating lattice potential. PACS numbers: 03.75.Lm, 03.75.Kk Quantized vortices are one of the most characteristic manifestations of superfluidity associated with a Bose-Einstein condensate (BEC) in atomic gases. By rotating anisotropic trap potentials, several experimental groups observed formation of triangular Abrikosov lattices of vortices in rotating BECs 1,2,3. Microscopic mechanism of the vortex lattice formation has been extensively studied both analytically and numerically using the Gross-Pitaevskii (GP) equation for the condensate wavefunction 4,5,6,7,8,9,10,11. More recently, the vortex phase diagrams of a BEC in rotating lattice potentials have attracted theoretical attention, since one expects vortex pinning and structural phase transition of vortex lattice structures 12,13,14. Recently, a rotating lattice has been experimentally realized at JILA, makinig use of a laser beam passing through a rotating mask 12. Stimulated by the recent JILA experiment, in this paper, we study vortex lattice structures of a BEC in a rotating triangular lattice potential created by blue-detuned laser beams. We numerically solve the two-dimensional Gross-Pitaevskii (GP) equa-T. Sato, T. Ishiyama and T. Nikuni Fig. 1. Density profile (a) and Structure factor profile (b) of BEC in the lattice potential. The lattice potential geometry is triangular lattice at a/aho = 2.2 and ?/aho = 0.65. tion in a frame rotationg with anguler velocity ?: (i ? ?)¯h ??(r,t)

Toshihiro Sato; Tomohiko Ishiyama; Tetsuro Nikuni

2006-01-01T23:59:59.000Z

215

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

216

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

217

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Wednesday, 25 November 2009 00:00 Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

218

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

219

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

220

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Magnetic thin-film nanostructures can exhibit a magnetic vortex state in which the magnetization vectors lie in the film plane and curl around in a closed loop. At the very center of the vortex, a small, stable core exists where the magnetization points either up or down out of the plane. Three years ago, the discovery of an easy core reversal mechanism at the ALS not only made the possibility of using such systems as magnetic memories much more realistic, it also initiated investigation of the core switching mechanism itself. Now, a Belgian-German-ALS collaboration has used high-resolution, time-resolved, magnetic x-ray microscopy to experimentally reveal the first step of the reversal process: the dynamic deformation of the vortex core. The group also measured a critical vortex velocity above which reversal occurs. Both these observations provide the first experimental support for the postulated reversal mechanism.

222

Near-Surface Vortex Structure in a Tornado and in a Sub-Tornado-Strength, Convective-Storm Vortex Observed by a Mobile, W-Band Radar During VORTEX2  

Science Conference Proceedings (OSTI)

As part of the VORTEX2 field campaign, a very high-resolution, mobile, W-band Doppler radar collected near-surface (?200 m AGL) observations in an EF-0 tornado near Tribune, Kansas on 25 May 2010 and in sub-tornado-strength vortices near Prospect ...

Robin L. Tanamachi; Howard B. Bluestein; Ming Xue; Wen-Chau Lee; Krzysztof A. Orzel; Stephen J. Frasier; Roger M. Wakimoto

223

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

DOE Green Energy (OSTI)

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

Ahsan Choudhuri

2011-03-31T23:59:59.000Z

224

Automated Sampling and Sample Pneumatic Transport of High Level Tank Wastes at the Hanford Waste Treatment Plant  

Science Conference Proceedings (OSTI)

This paper describes the development work, and design and engineering tasks performed, to provide a fully automated sampling system for the Waste Treatment Plant (WTP) project at the Hanford Site in southeastern Washington State, USA. WTP is being built to enable the emptying and immobilization of highly active waste resulting from processing of irradiated nuclear fuel since the 1940's. The Hanford Tank Wastes are separated into Highly Level Waste (HLW), and Low Active Waste (LAW) fractions, which are separately immobilized by vitrification into borosilicate glass. Liquid samples must be taken of the waste and Glass Forming Chemicals (GFCs) before vitrification, and analyzed to insure the glass products will comply with specifications established in the WTP contract. This paper describes the non-radioactive testing of the sampling of the HLW and LAW melter feed simulants that was performed ahead of final equipment design. These trials were essential to demonstrate the effectiveness and repeatability of the integrated sampling system to collect representative samples, free of cross-contamination. Based on existing tried and proven equipment, the system design is tailored to meet the WTP project's specific needs. The design provides sampling capabilities from 47 separate sampling points and includes a pneumatic transport system to move the samples from the 3 separate facilities to the centralized analytical laboratory. The physical and rheological compositions of the waste simulants provided additional challenges in terms of the sample delivery, homogenization, and sample capture equipment design requirements. The activity levels of the actual waste forms, specified as 486 E9 Bq/liter (Cs-137), 1.92 E9 Bq/liter (Co-60), and 9.67 E9 Bq/liter (Eu-154), influenced the degree of automation provided, and justified the minimization of manual intervention needed to obtain and deliver samples from the process facilities to the analytical laboratories. Maintaining high integrity primary and secondary confinement, including during the cross-site transportation of the samples, is a key requirement that is achieved and assured at all times. (authors)

Phillips, C.; Richardson, J. E. [BNG America, 2345 Stevens Drive, Richland, WA, 99354 (United States)

2006-07-01T23:59:59.000Z

225

Increase of pinning with temperature for a single vortex line in superfluid helium  

E-Print Network (OSTI)

While vortex pinning in superconductors usually becomes weaker at higher temperatures, we find the opposite behavior for a single vortex line in superfluid 4 He. The pinning steadily increases over our entire measurement range, from 0.15Tc to over 0.5Tc. We propose Kelvin waves along the vortex as a depinning mechanism with the observed temperature behavior. PACS numbers: 67.40.Vs, 74.60.Ge Pinning sites can trap vortices in a variety of systems. In superconductors, where vortex motion leads to non-zero resistance, a vast amount of work has been devoted to preventing such motion by introducing defects. Experimental work has shown that defects comparable in size to the vortex core make effective pin centers, and that straight [1] or splayed [2] line defects can increase the pin strength. Yet the mechanisms by which vortices interact with pin sites remain unresolved. Experimentally, pinning becomes weaker as temperature increases, in accord with the general assumption that depinning

L. A. K. Donev; L. Hough; R. J. Zieve

2000-01-01T23:59:59.000Z

226

Characterization of The Dalles Dam Spillbay 6 Vortex Using Surface Entrained Sensor Fish Device: Preliminary Report  

DOE Green Energy (OSTI)

This document summarizes the pilot study to characterize The Dalles Dam Spillbay 6 vortex using a surface entrained Sensor Fish device. It was conducted by Pacific Northwest National Laboratory (PNNL) on April 13 and 14, 2006. The total spill was controlled at approximately 110 kcfs, the forebay elevation was 157.89 ft, and the discharge of Bay 6 at the tested gate opening of 14 ft was approximately 18 kcfs. The objectives of the full study are to (1) develop baseline conditions for the detailed analysis of Sensor Fish measurements by deploying Sensor Fish in different surface locations in the vortex periphery; (2) observe the entrainment pattern and extract hydraulic data of interest such as acceleration, rotation, pressure, and estimated velocity of Sensor Fish or drogues; (3) integrate the experimental results with companion computational fluid dynamics (CFD) simulations and inertial particle tracking studies. A total of 12 Sensor Fish were released in the surface at upstream edge, left edge, downstream edge, and the core of the vortex at Bay 6. Because of the high discharge, the vortex patterns at the test condition were less consistent than the patterns observed at lower discharges. Compared with the Sensor Fish released at mid-bay at Bay 6, Sensor Fish released from the surface at the vortex experienced higher pressure fluctuations, a larger percentage of severe events, and much more rapid angular velocities.

Deng, Zhiqun; Richmond, Marshall C.; Carlson, Thomas J.

2006-06-22T23:59:59.000Z

227

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

DOE Green Energy (OSTI)

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

Griffin, O. M.

1980-03-14T23:59:59.000Z

228

Structure and Evolution of the Large-Scale Flow and an Embedded Upper-Tropospheric Cyclonic Vortex over Northeast Brazil  

Science Conference Proceedings (OSTI)

Horizontal structure and evolution of large-scale flow and an embedded synoptic-scale cyclonic vortex over northeast Brazil as separate systems and dynamical interaction between them are studied at 200 hPa. A quasi-stationary cyclonic vortex with ...

S. K. Mishra; V. B. Rao; M. A. Gan

2001-07-01T23:59:59.000Z

229

Evidence of small-scale magnetic concentrations dragged by vortex motion of solar photospheric plasma  

E-Print Network (OSTI)

Vortex-type motions have been measured by tracking bright points in high-resolution observations of the solar photosphere. These small-scale motions are thought to be determinant in the evolution of magnetic footpoints and their interaction with plasma and therefore likely to play a role in heating the upper solar atmosphere by twisting magnetic flux tubes. We report the observation of magnetic concentrations being dragged towards the center of a convective vortex motion in the solar photosphere from high-resolution ground-based and space-borne data. We describe this event by analyzing a series of images at different solar atmospheric layers. By computing horizontal proper motions, we detect a vortex whose center appears to be the draining point for the magnetic concentrations detected in magnetograms and well-correlated with the locations of bright points seen in G-band and CN images.

Balmaceda, L; Palacios, J; Cabello, I; Domingo, V

2010-01-01T23:59:59.000Z

230

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

Science Conference Proceedings (OSTI)

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

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

2012-11-20T23:59:59.000Z

231

Mitigation of Wind Turbine/Vortex Interaction Using Disturbance Accommodating Control  

DOE Green Energy (OSTI)

Wind turbines, a competitive source of emission-free electricity, are being designed with diameters and hub heights approaching 100 m, to further reduce the cost of the energy they produce. At this height above the ground, the wind turbine is exposed to atmospheric phenomena such as low-level jets, gravity waves, and Kelvin-Helmholtz instabilities, which are not currently modeled in wind turbine design codes. These atmospheric phenomena can generate coherent turbulence that causes high cyclic loads on wind turbine blades. These fluctuating loads lead to fatigue damage accumulation and blade lifetime reduction. Advanced control was used to mitigate vortex-induced blade cyclic loading. A full-state feedback controller that incorporates more detailed vortex inputs achieved significantly greater blade load reduction. Blade loads attributed to vortex passage, then, can be reduced through advanced control, and further reductions appear feasible.

Hand, M. M.

2003-12-01T23:59:59.000Z

232

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

DOE Patents (OSTI)

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

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

2009-10-20T23:59:59.000Z

233

Electron trapping by a current vortex F. Bentosela, a;b P. Exner, c;d and V.A. Zagrebnov a;b  

E-Print Network (OSTI)

with the magnetic field due to an electric current forming a localized rotationally symmetric vortex. We show simpler example involves a Pauli electron interacting with a flux tube modelling a vortex magnetic field field Ansatz. To illustrate this point we analyze in this letter the situation where the vortex current

234

Nonlinear Waves and Coherent Vortex Structures in Barotropic ?-plane Jets  

Science Conference Proceedings (OSTI)

We examine the nonlinear evolution of barotropic ?-plane jets on a periodic domain with a pseudospectral. A calculation of the linear growth rate yields an infected U-shaped curve on the ? versus k0 plane which separates regions of stability and ...

G. R. Flierl; P. Malanotte-Rizzoli; N. J. Zabusky

1987-09-01T23:59:59.000Z

235

Switching between stabilizing controllers  

Science Conference Proceedings (OSTI)

This paper deals with the problem of switching between several linear time-invariant (LTI) controllers-all of them capable of stabilizing a specific LTI process-in such a way that the stability of the closed-loop system is guaranteed for any switching ... Keywords: Hybrid systems, Impulse system, Realization theory, Stability theory, Switched systems

JoãO P. Hespanha; A.Stephen Morse

2002-11-01T23:59:59.000Z

236

Linear and Nonlinear Vortex Motion in an Asymmetric Balance Shallow Water Model  

Science Conference Proceedings (OSTI)

This work extends asymmetric balance (AB) theory to the beta plane (?-AB). The physical problem examined is the motion of a coherent vortex on a beta plane in a finite depth fluid in the absence of an environmental steering flow. A useful ...

Michael T. Montgomery; J. Dominique Möller; Christopher T. Nicklas

1999-03-01T23:59:59.000Z

237

Original articles: Vortex states in axially symmetric superconductors in applied magnetic field  

Science Conference Proceedings (OSTI)

We solve analytically the linearized Ginzburg-Landau (GL) equation in the presence of an uniform magnetic field with cylindrical boundary conditions. The solution of the non-linear GL equation is provided as an expansion in the basis of linearized solutions. ... Keywords: Axial magnetic field, Mesoscopic superconductivity, Nonlinear Ginzburg-Landau equation, Vortex

Andrei Ludu; Milorad V. Miloševi?; Francois M. Peeters

2012-03-01T23:59:59.000Z

238

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

E-Print Network (OSTI)

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

Paris-Sud XI, Université de

239

Longitudinally Dependent Ozone Increase in the Antarctic Polar Vortex Revealed by Balloon and Satellite Observations  

Science Conference Proceedings (OSTI)

The horizontal structure of processes causing increases in ozone in the Antarctic polar vortex was examined using data measured in 2003 from an ozonesonde observation campaign at Syowa Station (39.6°E, 69.0°S) and from the Improved Limb ...

K. Sato; Y. Tomikawa; G. Hashida; T. Yamanouchi; H. Nakajima; T. Sugita

2009-06-01T23:59:59.000Z

240

Aging memory and glassiness of a driven vortex , Guohong Li1  

E-Print Network (OSTI)

1 Aging memory and glassiness of a driven vortex system. Xu Du1 , Guohong Li1 , Eva Y. Andrei1 , M memory, aging and nonlinear-dynamics. Glasses[1-11], interfaces[12] and fractures are some examples[13 the deviation from equilibrium. After removing the force, the system ages with time and its subsequent response

Andrei, Eva Y.

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

3D-vortex labyrinths in the near field of solid-state microchip laser  

E-Print Network (OSTI)

The spatiotemporal vortex lattices generated in high Fresnel number solid-state microchip lasers are studied in connection with Talbot phenomenon generic to spatially periodic electromagnetic fields. The spatial layout of light field is obtained via dynamical model based on Maxwell-Bloch equations for class-B laser, discrete Fox-Lee map with relaxation of inversion and static model based on superposition of copropagating Gaussian beams. The spatial patterns observed experimentally and obtained numerically are interpreted as nonlinear superposition of vortices with helicoidal phase dislocations. The usage of vortex labyrinths and Talbot lattices as optical dipole traps for neutral atoms is considered for the wavelength of trapping radiation in the range 0.98 $\\div$ 2.79 $\\mu m$. The separable optical trapping potential is mounted as a sum of array of vortex lines and additional parabolic subtrap. The factorization of macroscopic wavefunction have led to analytical solution of Gross-Pitaevski equation for ground state of ensemble of quantum particles trapped in vortex labyrinth and in spatially - periodic array of Gaussian beams.

A. Yu. Okulov

2007-01-21T23:59:59.000Z

242

Ozone Forecasts of the Stratospheric Polar Vortex–Splitting Event in September 2002  

Science Conference Proceedings (OSTI)

The Southern Hemisphere major warming event in September 2002 has led to a breakup of the vortex in the middle and higher stratosphere and to a corresponding splitting of the ozone hole. Daily 3D ozone forecasts, produced at the Royal Netherlands ...

Henk Eskes; Arjo Segers; Peter van Velthoven

2005-03-01T23:59:59.000Z

243

Genesis of the Goshen County, Wyoming, Tornado on 5 June 2009 during VORTEX2  

Science Conference Proceedings (OSTI)

The genesis of a strong and long-lived tornado observed during the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) in Goshen County, Wyoming, on 5 June 2009 is studied. Mobile radar, mobile mesonet, rawinsonde, and ...

Karen Kosiba; Joshua Wurman; Yvette Richardson; Paul Markowski; Paul Robinson; James Marquis

2013-04-01T23:59:59.000Z

244

Asymptotic and numerical analysis of an inviscid bounded vortex flow at low Mach number  

Science Conference Proceedings (OSTI)

The inviscid low Mach number compressible flow developing from a plane incompressible vortex with constant density in a bounded domain is studied. A reference solution for this model flow is obtained by two-time scale asymptotic development in the zero ... Keywords: Asymptotic development, Compressible low Mach number flow, Explicit Roe scheme, Implicit scheme, WENO and high-order-compact schemes

Anne Cadiou; Lionel Le Penven; Marc Buffat

2008-09-01T23:59:59.000Z

245

Study of a Heavy Rain Vortex Formed over the Eastern Flank of the Tibetan Plateau  

Science Conference Proceedings (OSTI)

A case of the heavy rain vortex which occurred during the period 14–15 July 1979 is studied using a limited-area mesoscale numerical model. This is a representative example of a group of warm southwest vortices that often form over the eastern ...

Bin Wang; Isidoro Orlanski

1987-07-01T23:59:59.000Z

246

The Final Warming Date of the Antarctic Polar Vortex and Influences on its Interannual Variability  

Science Conference Proceedings (OSTI)

More than 40 years of radiosonde data from two Antarctic stations are examined for changes in the date of the final stratospheric warming that occurs each year as the vortex breaks up in spring/summer. A new measure of this date is derived that ...

Joanna D. Haigh; Howard K. Roscoe

2009-11-01T23:59:59.000Z

247

The Second Verification of the Origins of Rotation in Tornadoes Experiment: VORTEX2  

Science Conference Proceedings (OSTI)

The second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2), which had its field phases in May and June of 2009 and 2010, was designed to explore i) the physical processes of tornadogenesis, maintenance, and demise; ii) the ...

Joshua Wurman; David Dowell; Yvette Richardson; Paul Markowski; Erik Rasmussen; Donald Burgess; Louis Wicker; Howard B. Bluestein

2012-08-01T23:59:59.000Z

248

Electrodeposited Ag and Cu-stabilization Layer for High ...  

Science Conference Proceedings (OSTI)

... Materials Forensics, Three-dimensional Modeling and Fractal Characterization · Vortex Physics in Oxide and Pnictide High Temperature Superconductors.

249

Switching a magnetic vortex by interlayer coupling in epitaxially grown Co/Cu/Py/Cu(001) trilayer disks  

SciTech Connect

Epitaxial Py/Cu/Co/Cu(001) trilayers were patterned into micron sized disks and imaged using element-specific photoemission electron microscopy. By varying the Cu spacer layer thickness, we study how the coupling between the two magnetic layers influences the formation of magnetic vortex states. We find that while the Py and Co disks form magnetic vortex domains when the interlayer coupling is ferromagnetic, the magnetic vortex domains of the Py and Co disks break into anti-parallel aligned multidomains when the interlayer coupling is antiferromagnetic. We explain this result in terms of magnetic flux closure between the Py and Co layers for the antiferromagnetic coupling case.

Wu, J.; Carlton, D.; Oelker, E.; Park, J. S.; Jin, E.; Arenholz, E.; Scholl, A.; Hwang, C.; Bokor, J.; Qiu, Z Q

2010-07-16T23:59:59.000Z

250

Tropical Cyclone Initialization with a Spherical High-Order Filter and an Idealized Three-Dimensional Bogus Vortex  

Science Conference Proceedings (OSTI)

A tropical cyclone initialization method with an idealized three-dimensional bogus vortex of an analytic empirical formula is presented for the track and intensity prediction. The procedure in the new method consists of four steps: the separation ...

In-Hyuk Kwon; Hyeong-Bin Cheong

2010-04-01T23:59:59.000Z

251

Observations of a Terrain-Forced Mesoscale Vortex and Canyon Drainage Flows along the Front Range of Colorado  

Science Conference Proceedings (OSTI)

Observations taken during the February 1991 Atmospheric Studies in Complex Terrain (ASCOT) Winter Validation Study are used to describe the wind field associated with a terrain-forced mesoscale vortex and thermally forced canyon drainage flows ...

David H. Levinson; Robert M. Banta

1995-07-01T23:59:59.000Z

252

Convection-Allowing and Convection-Parameterizing Ensemble Forecasts of a Mesoscale Convective Vortex and Associated Severe Weather Environment  

Science Conference Proceedings (OSTI)

An analysis of a regional severe weather outbreak that was related to a mesoscale convective vortex (MCV) is performed. The MCV-spawning mesoscale convection system (MCS) formed in northwest Kansas along the southern periphery of a large cutoff ...

Adam J. Clark; William A. Gallus Jr.; Ming Xue; Fanyou Kong

2010-08-01T23:59:59.000Z

253

A Spatial Filter Approach to Evaluating the Role of Convection on the Evolution of a Mesoscale Vortex  

Science Conference Proceedings (OSTI)

A new spatial filter is proposed that exploits a spectral gap in power between the convective scale and the system (“vortex”) scale during tropical cyclone (TC) genesis simulations. Using this spatial separation, this study analyzes idealized ...

Glenn A. Creighton; Robert E. Hart; Philip Cunningham

2013-07-01T23:59:59.000Z

254

Probabilistic Evaluation of the Dynamics and Predictability of the Mesoscale Convective Vortex of 10–13 June 2003  

Science Conference Proceedings (OSTI)

This study examines the dynamics and predictability of the mesoscale convective vortex (MCV) of 10–13 June 2003 through ensemble forecasting. The MCV of interest developed from a preexisting upper-level disturbance over the southwest United ...

Daniel P. Hawblitzel; Fuqing Zhang; Zhiyong Meng; Christopher A. Davis

2007-04-01T23:59:59.000Z

255

Turbulence process domination under the combined forcings of wind stress, the Langmuir vortex force, and surface cooling  

Science Conference Proceedings (OSTI)

Turbulence in the ocean surface layer is generated by time-varying combinations of destabilizing surface buoyancy flux, wind stress forcing, and wave forcing through a vortex force associated with the surface wave field. Observations of time- and ...

A. E. Gargett; C. E. Grosch

256

Observations of a Squall Line and Its Near Environment Using High-Frequency Rawinsonde Launches during VORTEX2  

Science Conference Proceedings (OSTI)

Rawinsonde data were collected before and during passage of a squall line in Oklahoma on 15 May 2009 during the Second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2). Nine soundings were released within 3 h, allowing ...

George H. Bryan; Matthew D. Parker

2010-11-01T23:59:59.000Z

257

Contributions of the wall boundary layer to the formation of the counter-rotating vortex pair in transverse jets  

E-Print Network (OSTI)

Using high-resolution 3-D vortex simulations, this study seeks a mechanistic understanding of vorticity dynamics in transverse jets at a finite Reynolds number. A full no-slip boundary condition, rigorously formulated in ...

Schlegel, Fabrice

258

Variation in the Stratospheric Aerosol Associated with the North Cyclonic Polar Vortex as Measured by the SAM II Satellite Sensor  

Science Conference Proceedings (OSTI)

Aerosol extinction data obtained by the Stratospheric Aerosol Measurement II (SAM II) satellite instrument during the 1979/80 Northern Hemisphere winter season have been analyzed in relation to the cyclonic polar vortex. A synoptic approach has ...

G. S. Kent; C. R. Trepte; U. O. Farrukh; M. P. McCormick

1985-07-01T23:59:59.000Z

259

Stabilized radio frequency quadrupole  

DOE Patents (OSTI)

Disclosed is a long-vane stabilized radio frequency resonator for accelerating charged particles and including means defining a radio frequency resonator cavity, a plurality of long vanes mounted in the defining means for dividing the cavity into sections, and means interconnecting opposing ones of the plurality of vanes for stabilizing the resonator. 5 figs.

Lancaster, H.D.; Fugitt, J.A.; Howard, D.R.

1984-12-25T23:59:59.000Z

260

Heat transfer in a two-pass internally ribbed turbine blade coolant channel with cylindrical vortex generators  

DOE Green Energy (OSTI)

The effect of vortex generators on the mass (heat) transfer from the ribbed passage of a two pass turbine blade coolant channel is investigated with the intent of optimizing the vortex generator geometry so that significant enhancements in mass/heat transfer can be achieved. In the experimental configuration considered, ribs are mounted on two opposite walls; all four walls along each pass are active and have mass transfer from their surfaces but the ribs are non-participating. Mass transfer measurements, in the form of Sherwood number ratios, are made along the centerline and in selected inter-rib modules. Results are presented for Reynolds number in the range of 5,000 to 40,000, pitch to rib height ratios of 10.5 and 21, and vortex generator-rib spacing to rib height ratios of 0.55, and 1.5. Centerline and spanwise averaged Sherwood number ratios are presented along with contours of the Sherwood number ratios. Results indicate that the vortex generators induce substantial increases in the local mass transfer rates, particularly along the side walls, and modest increases in the average mass transfer rates. The vortex generators have the effect of making the inter-rib profiles along the ribbed walls more uniform. Along the side walls, horse-shoe vortices that characterize the vortex generator wake are associated with significant mass transfer enhancements. The wake effects and the levels of enhancement decrease somewhat with increasing Reynolds number and decreasing pitch.

Hibbs, R.; Acharya, S.; Chen, Y. [Louisiana State Univ., Baton Rouge, LA (United States)] [and others

1995-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


261

Visualizing Spacetime Curvature via Frame-Drag Vortexes and Tidal Tendexes II. Stationary Black Holes  

E-Print Network (OSTI)

When one splits spacetime into space plus time, the Weyl curvature tensor (which equals the Riemann tensor in vacuum) splits into two spatial, symmetric, traceless tensors: the tidal field $E$, which produces tidal forces, and the frame-drag field $B$, which produces differential frame dragging. In recent papers, we and colleagues have introduced ways to visualize these two fields: tidal tendex lines (integral curves of the three eigenvector fields of $E$) and their tendicities (eigenvalues of these eigenvector fields); and the corresponding entities for the frame-drag field: frame-drag vortex lines and their vorticities. These entities fully characterize the vacuum Riemann tensor. In this paper, we compute and depict the tendex and vortex lines, and their tendicities and vorticities, outside the horizons of stationary (Schwarzschild and Kerr) black holes; and we introduce and depict the black holes' horizon tendicity and vorticity (the normal-normal components of $E$ and $B$ on the horizon). For Schwarzschil...

Zhang, Fan; Nichols, David A; Chen, Yanbei; Lovelace, Geoffrey; Matthews, Keith D; Owen, Robert; Thorne, Kip S

2012-01-01T23:59:59.000Z

262

Effect of NO on extinction and re-ignition of vortex-perturbed hydrogen flames.  

DOE Green Energy (OSTI)

The catalytic effect of nitric oxide (NO) on the dynamics of extinction and re-ignition of a vortex-perturbed non-premixed hydrogen-air flame is studied in a counterflow burner. A diffusion flame is established with counterflowing streams of nitrogen-diluted hydrogen at ambient temperature and air heated to a range of temperatures that brackets the auto-ignition temperature. Localized extinction is induced by impulsively driving a fuel-side toroidal vortex into the steady flame, and the recovery of the extinguished region is monitored by planar laser-induced fluorescence (PLIF) of the hydroxyl radical (OH). The dynamics of flame recovery depend on the air temperature and fuel concentration, and four different recovery modes are identified. These modes involve combinations of edge-flame propagation and the expansion of an auto-ignition kernel that forms within the extinguished region. The addition of a small amount of NO significantly alters the re-ignition process by shifting the balance between chain-termination and chain-propagation reactions to enhance auto-ignition. The ignition enhancement by this catalytic effect causes a shift in the conditions that govern the recovery modes. In addition, the effects of NO concentration and vortex strength on the flame recovery are examined. Direct numerical simulations of the flame-vortex interaction with and without NO doping show how the small amount of OH produced by NO-catalyzed reactions has a significant impact on the development of an auto-ignition kernel. This joint experimental and numerical study provides detailed insight into the interaction between transient flows and ignition processes.

Yoo, Chun Sang; Chen, Jacqueline H.; Frank, Jonathan H.; Lee, Uen Do (KITECH, Cheonan, Chungnam, South Korea)

2009-01-01T23:59:59.000Z

263

Tripolar vortex formation in dense quantum plasma with ion-temperature-gradients  

SciTech Connect

We have derived system of nonlinear equations governing the dynamics of low-frequency electrostatic toroidal ion-temperature-gradient mode for dense quantum magnetoplasma. For some specific profiles of the equilibrium density, temperature, and ion velocity gradients, the nonlinear equations admit a stationary solution in the form of a tripolar vortex. These results are relevant to understand nonlinear structure formation in dense quantum plasmas in the presence of equilibrium ion-temperature and density gradients.

Qamar, Anisa; Ata-ur-Rahman [Institute of Physics and Electronics, University of Peshawar, Khyber Pakhtoon Khwa 25000 (Pakistan); National Center for Physics Shahdrah Valley Road, Islamabad 44000 (Pakistan); Mirza, Arshad M. [Theoretical Plasma Physics Group, Physics Department, Quaid-i-Azam University, Islamabad 45320 (Pakistan)

2012-05-15T23:59:59.000Z

264

Numerical evidence of breaking of vortex lines in an ideal fluid  

E-Print Network (OSTI)

Emergence of singularity of vorticity at a single point, not related to any symmetry of the initial distribution, has been demonstrated numerically for the first time. Behavior of the maximum of vorticity near the point of collapse closely follows the dependence 1/(t0-t), where t0 is the time of collapse. This agrees with the interpretation of collapse in an ideal incompressible fluid as of the process of vortex lines breaking.

Kuznetsov, E A; Zheligovsky, V A

2001-01-01T23:59:59.000Z

265

Surface controlled blade stabilizer  

DOE Patents (OSTI)

Drill string stabilizer apparatus, controllable to expand and retract entirely from the surface by control of drill string pressure, wherein increase of drill string pressure from the surface closes a valve to create a piston means which is moved down by drill string pressure to expand the stabilizer blades, said valve being opened and the piston moving upward upon reduction of drill string pressure to retract the stabilizer blades. Upward and downward movements of the piston and an actuator sleeve therebelow are controlled by a barrel cam acting between the housing and the actuator sleeve.

Russell, Larry R. (6025 Edgemor, Suite C, Houston, TX 77081)

1983-01-01T23:59:59.000Z

266

Visualizing Spacetime Curvature via Frame-Drag Vortexes and Tidal Tendexes II. Stationary Black Holes  

E-Print Network (OSTI)

When one splits spacetime into space plus time, the Weyl curvature tensor (which equals the Riemann tensor in vacuum) splits into two spatial, symmetric, traceless tensors: the tidal field $E$, which produces tidal forces, and the frame-drag field $B$, which produces differential frame dragging. In recent papers, we and colleagues have introduced ways to visualize these two fields: tidal tendex lines (integral curves of the three eigenvector fields of $E$) and their tendicities (eigenvalues of these eigenvector fields); and the corresponding entities for the frame-drag field: frame-drag vortex lines and their vorticities. These entities fully characterize the vacuum Riemann tensor. In this paper, we compute and depict the tendex and vortex lines, and their tendicities and vorticities, outside the horizons of stationary (Schwarzschild and Kerr) black holes; and we introduce and depict the black holes' horizon tendicity and vorticity (the normal-normal components of $E$ and $B$ on the horizon). For Schwarzschild and Kerr black holes, the horizon tendicity is proportional to the horizon's intrinsic scalar curvature, and the horizon vorticity is proportional to an extrinsic scalar curvature. We show that, for horizon-penetrating time slices, all these entities ($E$, $B$, the tendex lines and vortex lines, the lines' tendicities and vorticities, and the horizon tendicities and vorticities) are affected only weakly by changes of slicing and changes of spatial coordinates, within those slicing and coordinate choices that are commonly used for black holes. [Abstract is abbreviated.

Fan Zhang; Aaron Zimmerman; David A. Nichols; Yanbei Chen; Geoffrey Lovelace; Keith D. Matthews; Robert Owen; Kip S. Thorne

2012-08-15T23:59:59.000Z

267

Nanoscale strain-induced pair suppression as a vortex-pinning mechanism in high- temperature superconductors  

SciTech Connect

Boosting large-scale superconductor applications require nanostructured conductors with artificial pinning centres immobilizing quantized vortices at high temperature and magnetic fields. Here we demonstrate a highly effective mechanism of artificial pinning centers in solution-derived high-temperature superconductor nanocomposites through generation of nanostrained regions where Cooper pair formation is suppressed. The nanostrained regions identified from transmission electron microscopy devise a very high concentration of partial dislocations associated with intergrowths generated between the randomly oriented nanodots and the epitaxial YBa{sub 2}Cu{sub 3}O{sub 7} matrix. Consequently, an outstanding vortex-pinning enhancement correlated to the nanostrain is demonstrated for four types of randomly oriented nanodot, and a unique evolution towards an isotropic vortex-pinning behaviour, even in the effective anisotropy, is achieved as the nanostrain turns isotropic. We suggest a new vortex-pinning mechanism based on the bond-contraction pairing model, where pair formation is quenched under tensile strain, forming new and effective core-pinning regions.

Llordes, Anna [ICMAB, Barcelona, Spain; Palau, A. [ICMAB, Barcelona, Spain; Gazquez, J. [Oak Ridge National Laboratory (ORNL); Coll, M. [ICMAB, Barcelona, Spain; Vlad, R. [ICMAB, Barcelona, Spain; Pomar, A. [ICMAB, Barcelona, Spain; Arbiol, Jordi [ICMAB, Barcelona, Spain; Guzman, Roger [ICMAB, Barcelona, Spain; Ye, S. [ICMAB, Barcelona, Spain; Rouco, V [ICMAB, Barcelona, Spain; Sandiumenge, Felip [ICMAB, Barcelona, Spain; Ricart, Susagna [ICMAB, Barcelona, Spain; Puig, Teresa [ICMAB, Barcelona, Spain; Varela del Arco, Maria [ORNL; Chataigner, D. [CRISMAT, Caen, France; Vanacken, J. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Gutierrez, J. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Moschalkov, V. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Deutscher, G. [Tel Aviv University; Magen Dominguez, Cesar [ORNL; Obradors, Xavier [ICMAB, Barcelona, Spain

2012-01-01T23:59:59.000Z

268

Further research, development and commercialization of the hydro-pneumatic apparatus for harnessing ultra low-head hydropower. Progress report, January 1--July 31, 1996  

DOE Green Energy (OSTI)

The main research thrust of this period was devoted to development, construction and preparation to laboratory testing of two new power converters of higher than the old converter capacity. These converters should develop substantially larger air flow rate to test the authors new air helical turbines, combined with air chambers. Major tasks of this part of the project are completion of the gate control mechanism; continuation of the assessment of air turbine options including construction and testing a helical delta shape turbine for hydro-pneumatic power converters; completion of construction of larger power converters including gates and control systems; development of test plan; procure test equipment; preparation to the tests; and development and construction of a new converter with louvre-type gate system. During this period the gate control system was tested in various mechanical combinations. The tests validated reliability and integrity of the developed mechanism. The design of the control system can be recommended for practical applications. Phases of operation of the control system are shown.

Gorlov, A.M.

1996-12-31T23:59:59.000Z

269

Ignitions in mixtures of coal dust, air, and methane from abrasive impacts of hard minerals with pneumatic pipeline steel. Report of investigations 1976  

SciTech Connect

Laboratory equipment which simulated abrasive impacts between steel and minerals as might occur during pneumatic transport of coal was used by the Bureau of Mines to characterize the potential explosion hazard due to such collisions in an atmosphere of fine coal dust-air-methane. A variety of coal mine rock materials, including sandstone, limestone, and pyrite-bearing limestone, were impacted with specimens of pipeline steel. Tests were conducted in atmospheres containing zero to 6.4 vol-pct methane mixed with zero to 300 mg/l coal dust. Coal dust-air alone was not ignited by abrasive impacts, but additions of as little as 1 vol-pct methane to coal dust-air resulted in ignitions. Steel impacting against sandstone caused ignitions in coal-air-methane mixtures with the probability for ignitions increasing with an increase in methane. Ignitions in coal-air-methane were found to be caused by a hot friction-induced smear on the impacted rock at the impact site rather than by sparks. High-speed photography was used to verify this observation.

Kelley, J.E.; Forkner, B.L.

1976-01-01T23:59:59.000Z

270

Hygrometry with Temperature Stabilization  

Science Conference Proceedings (OSTI)

A method is presented for stabilizing the temperature of air to allow the use of temperature-sensitive, humidity sensors for direct determination of an invariant humidity characteristic such as specific humidity and/or its fluctuations. Problems ...

Krzysztof E. Haman; Andrzej M. Makulski

1985-12-01T23:59:59.000Z

271

Thermal Stabilization Blend Plan  

SciTech Connect

This Blend Plan documents the feed material items that are stored in 2736-2 vaults, the 2736-ZB 638 cage, the 192C vault, and the 225 vault that will be processed through the thermal stabilization furnaces. The purpose of thermal stabilization is to heat the material to 1000 degrees Celsius to drive off all water and leave the plutonium and/or uranium as oxides. The stabilized material will be sampled to determine the Loss On Ignition (LOI) or percent water. The stabilized material must meet water content or LOI of less than 0.5% to be acceptable for storage under DOE-STD-3013-99 specifications. Out of specification material will be recycled through the furnaces until the water or LOI limits are met.

RISENMAY, H.R.

2000-05-02T23:59:59.000Z

272

Aquifer stability investigations  

DOE Green Energy (OSTI)

The study of compressed air energy storage (CAES) in porous rock reservoirs is carried out within the Reservoir Stability Studies Program at Pacific Northwest Laboratory. The goal of the study is to establish criteria for long-term stability of aquifer CAES reservoirs. These criteria are intended to be guidelines and check lists that utilities and architect-engineering firms may use to evaluate reservoir stability at candidate CAES sites. These criteria will be quantitative where possible, qualitative where necessary, and will provide a focal point for CAES relevant geotechnical knowledge, whether developed within this study or available from petroleum, mining or other geotechnical practices using rock materials. The Reservoir Stability Studies Program had four major activities: a state-of-the-art survey to establish preliminary stability criteria and identify areas requiring research and development; numerical modeling; laboratory testing to provide data for use in numerical models and to investigate fundamental rock mechanics, thermal, fluid, and geochemical response of aquifer materials; and field studies to verify the feasibility of air injection and recovery under CAES conditions in an aquifer, to validate and refine the stability criteria, and to evaluate the accuracy and adequacy of the numerical and experimental methodologies developed in previous work. Three phases of study, including preliminary criteria formulation, numerical model development, and experimental assessment of CAES reservoir materials have been completed. Present activity consists of construction and operation of the aquifer field test, and associated numerical and experimental work in support of that activity. Work is presently planned to be complete by 1983 at the end of the field test. At that time the final stability criteria for aquifers will be issued. Attached here also are preliminary criteria for aquifers.

Allen, R.D.; Doherty, T.J.

1981-09-01T23:59:59.000Z

273

Stability of growing vesicles  

E-Print Network (OSTI)

We investigate the stability of growing vesicles using the formalism of nonequilibrium thermodynamics. The vesicles are growing due to the accretion of lipids to the bilayer which forms the vesicle membrane. The thermodynamic description is based on the hydrodynamics of a water{/}lipid mixture together with a model of the vesicle as a discontinuous system in the sense of linear nonequilibrium thermodynamics. This formulation allows the forces and fluxes relevant to the dynamic stability of the vesicle to be identified. The method is used to analyze the stability of a spherical vesicle against arbitrary axisymmetric perturbations. It is found that there are generically two critical radii at which changes of stability occur. In the case where the perturbation takes the form of a single zonal harmonic, only one of these radii is physical and is given by the ratio $2 L_p / L_\\gamma$, where $L_p$ is the hydraulic conductivity and $L_\\gamma$ is the Onsager coefficient related to changes in membrane area due to lipid accretion. The stability of such perturbations is related to the value of $l$ corresponding to the particular zonal harmonic: those with lower $l$ are more unstable than those with higher $l$. Possible extensions of the current work and the need for experimental input are discussed.

Richard G. Morris; Alan J. McKane

2010-12-15T23:59:59.000Z

274

Stabilized PV system  

DOE Patents (OSTI)

A stabilized PV system comprises an array of photovoltaic (PV) assemblies mounted to a support surface. Each PV assembly comprises a PV module and a support assembly securing the PV module to a position overlying the support surface. The array of modules is circumscribed by a continuous, belt-like perimeter assembly. Cross strapping, extending above, below or through the array, or some combination of above, below and through the array, secures a first position along the perimeter assembly to at least a second position along the perimeter assembly thereby stabilizing the array against wind uplift forces. The first and second positions may be on opposite sides on the array.

Dinwoodie, Thomas L. (Piedmont, CA)

2002-12-17T23:59:59.000Z

275

Charged Vacuum Bubble Stability  

E-Print Network (OSTI)

A type of scenario is considered where electrically charged vacuum bubbles, formed from degenerate or nearly degenerate vacuua separated by a thin domain wall, are cosmologically produced due to the breaking of a discrete symmetry, with the bubble charge arising from fermions residing within the domain wall. Stability issues associated with wall tension, fermion gas, and Coulombic effects for such configurations are examined. The stability of a bubble depends upon parameters such as the symmetry breaking scale and the fermion coupling. A dominance of either the Fermi gas or the Coulomb contribution may be realized under certain conditions, depending upon parameter values.

J. R. Morris

1998-10-20T23:59:59.000Z

276

Interconversion of dark soliton and Josephson vortex in a quasi-1D long Bose Josephson junction  

E-Print Network (OSTI)

Dark soliton (DS) and Josephson vortex (JV) in quasi-1D long Bose Josephson junction (BJJ) can be interconverted by tuning Josephson coupling. Rates of the interconversion as well as of the thermally activated phase-slip effect, resulting in the JV switching its vorticity, have been evaluated. The role of quantum phase-slip in creating superposition of JVs with opposite vorticities as a qubit is discussed as well. Utilization of the JV for controlled and coherent transfer of atomic Bose-Einstein condensate (BEC) is suggested.

V. M. Kaurov; A. B. Kuklov

2003-12-03T23:59:59.000Z

277

Stabilized chromium oxide film  

DOE Patents (OSTI)

Stabilized air-oxidized chromium films deposited on high-power klystron ceramic windows and sleeves having a thickness between 20 and 150.ANG. are useful in lowering secondary electron emission yield and in avoiding multipactoring and window failure due to overheating. The ceramic substrate for the film is chosen from alumina, sapphire or beryllium oxide.

Garwin, Edward L. (Los Altos, CA); Nyaiesh, Ali R. (Palo Alto, CA)

1988-01-01T23:59:59.000Z

278

Stabilized chromium oxide film  

DOE Patents (OSTI)

Stabilized air-oxidized chromium films deposited on high-power klystron ceramic windows and sleeves having a thickness between 20 and 150A are useful in lowering secondary electron emission yield and in avoiding multipactoring and window failure due to overheating. The ceramic substrate for the film is chosen from alumina, sapphire or beryllium oxide.

Nyaiesh, A.R.; Garwin, E.L.

1986-08-04T23:59:59.000Z

279

Probing the spin polarization of current by soft x-ray imaging of current-induced magnetic vortex dynamics  

SciTech Connect

Time-resolved soft X-ray transmission microscopy is applied to image the current-induced resonant dynamics of the magnetic vortex core realized in a micron-sized Permalloy disk. The high spatial resolution better than 25 nm enables us to observe the resonant motion of the vortex core. The result also provides the spin polarization of the current to be 0.67 {+-} 0.16 for Permalloy by fitting the experimental results with an analytical model in the framework of the spin-transfer torque.

Kasai, Shinya; Fischer, Peter; Im, Mi-Young; Yamada, Keisuke; Nakatani, Yoshinobu; Kobayashi, Kensuke; Kohno, Hiroshi; Ono, Teruo

2008-12-09T23:59:59.000Z

280

Combustion Stability in Complex Engineering Flows | Argonne Leadership...  

NLE Websites -- All DOE Office Websites (Extended Search)

vortex. Virtual testing enables engineers to design next-generation, low-emission combustion systems. Lee Shunn, Cascade Technologies; Shoreh Hajiloo, GE Global Research...

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

On the dynamics of flame edges in diffusion-flame/vortex interactions  

Science Conference Proceedings (OSTI)

We analyze the local flame extinction and reignition of a counterflow diffusion flame perturbed by a laminar vortex ring. Local flame extinction leads to the appearance of flame edges separating the burning and extinguished regions of the distorted mixing layer. The dynamics of these edges is modeled based on previous numerical results, with heat release effects fully taken into account, which provide the propagation velocity of triple and edge flames in terms of the upstream unperturbed value of the scalar dissipation. The temporal evolution of the mixing layer is determined using the classical mixture fraction approach, with both unsteady and curvature effects taken into account. Although variable density effects play an important role in exothermic reacting mixing layers, in this paper the description of the mixing layer is carried out using the constant density approximation, leading to a simplified analytical description of the flow field. The mathematical model reveals the relevant nondimensional parameters governing diffusion-flame/vortex interactions and provides the parameter range for the more relevant regime of local flame extinction followed by reignition via flame edges. Despite the simplicity of the model, the results show very good agreement with previously published experimental results. (author)

Hermanns, Miguel; Linan, Amable [Departamento de Motopropulsion y Termofluidodinamica, Universidad Politecnica de Madrid, Pza. Cardenal Cisneros 3, 28040 Madrid (Spain); Vera, Marcos [Area de Mecanica de Fluidos, Universidad Carlos III de Madrid, 28911 Leganes (Spain)

2007-04-15T23:59:59.000Z

282

Combustion of pulverized coal in vortex structures. Final report, October 1, 1993--December 31, 1995  

Science Conference Proceedings (OSTI)

The objectives of the project were: (i) to understand the effects of heating one of the streams on the characteristics of shear layers, (ii) to investigate the changes in the characteristics of large scale vortex structures in the shear layer caused by the introduction of inert solid particles in one of the feed streams; (iii) to understand the effects of pyrolyzing solids on the shear layer behavior; and (iv) to study the effects of combustion of particles and their pyrolysis products on the shear layer structure, heat release rate, and pollutant emission characteristics. An experimental facility for generating two-dimensional shear layers containing vortex structures has been designed and fabricated. The experimental facility is essentially a low speed wind tunnel designed to (i) provide two gas streams, initially with uniform velocity profiles and isotropic turbulence, mixing at the end of a splitter plate, (ii) introduce vorticity by passively perturbing one of the streams, (iii) allow heating of one of the streams to temperatures high enough to cause pyrolysis of coal particles, and (iv) provide a natural gas flame in one of the streams to result in ignition and burning of coal particles.

Gollahalli, S.R.; Butuk, N.

1996-03-01T23:59:59.000Z

283

Stabilized floating platforms  

DOE Patents (OSTI)

The subject invention is directed to a floating platform for supporting nuclear reactors and the like at selected offshore sites. The platform is provided with a stabilizer mechanism which significantly reduces the effects of wave action upon the platform and which comprises a pair of relatively small floats attached by rigid booms to the platform at locations spaced therefrom for reducing wave pitch, acceleration, and the resonance period of the wave.

Thomas, David G. (Oak Ridge, TN)

1976-01-01T23:59:59.000Z

284

Stability of ferroelectric ice  

E-Print Network (OSTI)

We theoretically study the stability conditions of the ferroelectric ice of the Cmc21 structure, which has been considered, for decades, one of the most promising candidates of the low temperature proton-ordered phase of pure ice Ih. It turned out that the Cmc21 structure is stable only with a certain amount of dopant and the true proton-ordered phase of pure ice Ih remains to be found at lower temperature. Implication for spin ice is mentioned.

Iitaka, Toshiaki

2010-01-01T23:59:59.000Z

285

Breakthrough in stability assessment  

SciTech Connect

Maintaining a stable flow of electricity is critical for secure power grid operation and customer satisfaction. Recently, a breakthrough method was developed for enhancing the stability of electricity flow. The application of this method, which is based on a 100-year-old mathematical concept known as normal forms, promises to increase power system efficiency by improving utilities` ability to predict and control grid behavior. 9 figs.

Haase, P.

1996-07-01T23:59:59.000Z

286

Quantum convolutional stabilizer codes  

E-Print Network (OSTI)

Quantum error correction codes were introduced as a means to protect quantum information from decoherance and operational errors. Based on their approach to error control, error correcting codes can be divided into two different classes: block codes and convolutional codes. There has been significant development towards finding quantum block codes, since they were first discovered in 1995. In contrast, quantum convolutional codes remained mainly uninvestigated. In this thesis, we develop the stabilizer formalism for quantum convolutional codes. We define distance properties of these codes and give a general method for constructing encoding circuits, given a set of generators of the stabilizer of a quantum convolutional stabilizer code, is shown. The resulting encoding circuit enables online encoding of the qubits, i.e., the encoder does not have to wait for the input transmission to end before starting the encoding process. We develop the quantum analogue of the Viterbi algorithm. The quantum Viterbi algorithm (QVA) is a maximum likehood error estimation algorithm, the complexity of which grows linearly with the number of encoded qubits. A variation of the quantum Viterbi algorithm, the Windowed QVA, is also discussed. Using Windowed QVA, we can estimate the most likely error without waiting for the entire received sequence.

Chinthamani, Neelima

2005-05-01T23:59:59.000Z

287

Measuring Atmospheric Stability with GPS  

Science Conference Proceedings (OSTI)

Nowcasting of convective systems plays a crucial role in weather forecasting. The strength of convection depends on the (in)stability of the air column. The stability can be detected by radiosonde observations. However, these observations are not ...

Siebren de Haan

2006-03-01T23:59:59.000Z

288

Static Stability—An Update  

Science Conference Proceedings (OSTI)

Static stability should not be evaluated from the local lapse rate. There is a growing body of observations, such as within portions of mixed layers and forest canopies, showing that the whole sounding should be considered to evaluate stability. ...

Roland B. Stull

1991-10-01T23:59:59.000Z

289

Tracking Waves and Vortex Nucleation in Excitable Systems with Anomalous Dispersion N. Manz, C.T. Hamik, and O. Steinbock  

E-Print Network (OSTI)

Tracking Waves and Vortex Nucleation in Excitable Systems with Anomalous Dispersion N. Manz, C of the underlying anomalous dispersion relation. DOI: 10.1103/PhysRevLett.92.248301 PACS numbers: 82.40.Ck, 05.45.­a and physicochemical systems [1,2]. Important examples include neuronal and cardiac tissue as well as gas discharge

Steinbock, Oliver

290

Optimizing the WSR-88D Mesocyclone/Tornadic Vortex Signature Algorithm Using WATADS—A Case Study  

Science Conference Proceedings (OSTI)

A tornado outbreak occurred in east-central Minnesota around 0000 UTC 22 July 1995, within 80 km of the KMPX WSR-88D, at the Minneapolis–Chanhassen Weather Service Forecast Office (WSFO). The WSR-88D Mesocyclone/Tornadic Vortex Signature ...

Gregory A. Tipton; Eric D. Howieson; John A. Margraf; Robert R. Lee

1998-06-01T23:59:59.000Z

291

ECMWF Analyses and Forecasts of Stratospheric Winter Polar Vortex Breakup: September 2002 in the Southern Hemisphere and Related Events  

Science Conference Proceedings (OSTI)

Breakup of the polar stratospheric vortex in the Northern Hemisphere is an event that is known to be predictable for up to a week or so ahead. This is illustrated using data from the 45-yr ECMWF Re-Analysis (ERA-40) for the sudden warmings of ...

Adrian Simmons; Mariano Hortal; Graeme Kelly; Anthony McNally; Agathe Untch; Sakari Uppala

2005-03-01T23:59:59.000Z

292

Soliton trains and vortex streets as a form of Cerenkov radiation in trapped Bose-Einstein condensates  

Science Conference Proceedings (OSTI)

We numerically study the nucleation of gray solitons and vortex-antivortex pairs created by a moving impurity in, respectively, 1D and 2D Bose-Einstein condensates (BECs) confined by a parabolic potential. The simulations emulate the motion of a localized ... Keywords: Bose-Einstein condensation, Matter waves, Nucleation, Solitons, Vortices

R. Carretero-González; P. G. Kevrekidis; D. J. Frantzeskakis; B. A. Malomed; S. Nandi; A. R. Bishop

2007-03-01T23:59:59.000Z

293

Vortex Rossby Waves in a Numerically Simulated Tropical Cyclone. Part II: The Role in Tropical Cyclone Structure and Intensity Changes  

Science Conference Proceedings (OSTI)

In Part I, the author analyzed the asymmetric structure in the inner core of a numerically simulated tropical cyclone and found that the asymmetry near the eyewall in the mid–lower troposphere is dominated by wavenumber-1 and -2 vortex Rossby ...

Yuqing Wang

2002-04-01T23:59:59.000Z

294

Chassis stabilization system  

DOE Patents (OSTI)

A stabilizing suspension system is provided for vehicles carrying telescopic booms or aerial work platforms having a fixed axle and a oscillating axle. Hydraulic cylinders are connected to each end of the oscillating axle, each cylinder being capable of extending and retracting. An off level sensor senses the angle of tilt of the chassis in both left and right directions and, when a predetermined threshold of tilt has been detected, the hydraulic cylinder on the downhill side of the chassis is locked against retracting, but is free to move in the downhill direction to allow the downhill wheel to remain in contact with the ground.

Claxton, Gerald L. (Fresno, CA)

1999-01-01T23:59:59.000Z

295

Thermal Stabilization Blend Plan  

SciTech Connect

The Blend Plan was written to identify items stored outside of the 213 MBA that will be moved into the MBA for thermal stabilization processing. Product quality oxide items stored in our vaults are found in Appendix A. A table is included in Appendix A which details the isotopic values for the oxide items and calculates the amount of material of any specific run that can be placed in a product can and maintain the 15 watt limit to meet storage vault specifications. This Revision of the Blend Plan adds items of lesser dose rate to lower the exposure of the workers until additional shielding can be added to the gloveboxes.

RISENMAY, H.R.

2000-04-20T23:59:59.000Z

296

Method for the detection of a magnetic field utilizing a magnetic vortex  

SciTech Connect

The determination of the strength of an in-plane magnetic field utilizing one or more magnetically-soft, ferromagnetic member, having a shape, size and material whereas a single magnetic vortex is formed at remanence in each ferromagnetic member. The preferred shape is a thin circle, or dot. Multiple ferromagnetic members can also be stacked on-top of each other and separated by a non-magnetic spacer. The resulting sensor is hysteresis free. The sensor's sensitivity, and magnetic saturation characteristics may be easily tuned by simply altering the material, size, shape, or a combination thereof to match the desired sensitivity and saturation characteristics. The sensor is self-resetting at remanence and therefore does not require any pinning techniques.

Novosad, Valentyn (Chicago, IL); Buchanan, Kristen (Batavia, IL)

2010-04-13T23:59:59.000Z

297

Characterization of waste tire incineration in a prototype vortexing fluidized bed combustor  

Science Conference Proceedings (OSTI)

To investigate the characteristics of incinerating waste tires in a prototype vortexing fluidized bed combustor, performance tests were conducted with two sizes of waste tire fragments. The results from the combustion experiments showed that increasing the tire particle size caused less of the volatiles to be burned in the freeboard and thus lowered freeboard temperature. Uniform bed temperature could also be achieved by increasing the size of the tire particles. Variations in the secondary and tertiary air rates simultaneously affected the swirling intensity and the axial gas velocity in the freeboard, and thus resulted in the variations in ash elutriation, combustion efficiency, and pollutant emissions for the combustion systems. 21 refs., 17 figs., 1 tab.

Teng, H.; Chyang, C.S.; Shang, S.H.; Ho, J.A. [Chung Yuan Christian Univ., Chung-Li (Taiwan, Province of China)

1997-01-01T23:59:59.000Z

298

Simulations of 2D magnetic electron drift vortex mode turbulence in plasmas  

E-Print Network (OSTI)

Simulations are performed to investigate turbulent properties of nonlinearly interacting two-dimensional (2D) magnetic electron drift vortex (MEDV) modes in a nonuniform unmagnetized plasma. The relevant nonlinear equations governing the dynamics of the MEDV modes are the wave magnetic field and electron temperature perturbations in the presence of the equilibrium density and temperature gradients. The important nonlinearities come from the advection of the electron fluid velocity perturbation and the electron temperature, as well as from the nonlinear electron Lorentz force. Computer simulations of the governing equations for the nonlinear MEDV modes reveal the generation of streamer-like electron flows, such that the corresponding gradients in the direction of the inhomogeneities tend to flatten out. By contrast, the gradients in an orthogonal direction vary rapidly. Consequently, the inertial range energy spectrum in decaying MEDV mode turbulence exhibits a much steeper anisotropic spectral index. The magn...

Shaikh, Dastgeer

2008-01-01T23:59:59.000Z

299

Effects of surface roughness and vortex generators on the LS(1)-0417MOD airfoil  

DOE Green Energy (OSTI)

An 18-inch constant-chord model of the LS(l)-0417MOD airfoil section was tested under two dimensional steady state conditions ate University 7{times}10 Subsonic Wind Tunnel. The objective was to document section lift and moment characteristics model and air flow conditions. Surface pressure data was acquired at {minus}60{degrees} through + 230{degrees} geometric angles of attack, at a nominal 1 million Reynolds number. Cases with and without leading edge grit roughness were investigated. The leading edge mulated blade conditions in the field. Additionally, surface pressure data were acquired for Reynolds numbers of 1.5 and 2.0 million, with and without leading edge grit roughness; the angle of attack was limited to a {minus}20{degrees} to 40{degrees} range. In general, results showed lift curve slope sensitivities to Reynolds number and roughness. The maximum lift coefficient was reduced as much as 29% by leading edge roughness. Moment coefficient showed little sensitivity to roughness beyond 50{degrees} angle of attack, but the expected decambering effect of a thicker boundary layer with roughness did show at lower angles. Tests were also conducted with vortex generators located at the 30% chord location on the upper surface only, at 1 and 1.5 million Reynolds numbers, with and without leading edge grit roughness. In general, with leading edge grit roughness applied, the vortex generators restored 85 percent of the baseline level of maximum lift coefficient but with a more sudden stall break and at a higher angle of attack than the baseline.

Reuss, R.L.; Hoffman, M.J.; Gregorek, G.M. [Ohio State Univ., Columbus, OH (United States)

1995-12-01T23:59:59.000Z

300

Stability Breakout Session  

NLE Websites -- All DOE Office Websites (Extended Search)

Breakout Session Breakout Session I Chemical Stability * What are the Reactions? i. Products must be identified (loss of IEC is not enough) ii. Establish reaction mechanism(s) iii. Measure the kinetics II Reaction of membrane with OH - /HCO 3 - /CO 3 2- at various hydration levels - nucleophilicity and basicity of anion species i. Cations a) Small molecule analogues b) Effects of hydration state and temperature c) Cation design R 4 N + ???? Families of cations * Ammoniums * Guanadiniums * Sulfoniums * Phosphoniums [problematic] * Phosphazeniums II Reaction with OH - /HCO 3 - /CO 3 2- and Hydration levels (cont'd) ii. Tethers - Link to cation - Link to backbone - Spacers (in between) iii. Backbone a) Hydrocarbon - Structure - Functional makeup b) Fluoropolymer III Reactive O 2 Species HOO - /H

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
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301

Laser controlled flame stabilization  

DOE Patents (OSTI)

A method and apparatus is provided for initiating and stabilizing fuel combustion in applications such as gas turbine electrical power generating engines and jet turbine engines where it is desired to burn lean fuel/air mixtures which produce lower amounts of NO.sub.x. A laser induced spark is propagated at a distance from the fuel nozzle with the laser ignitor being remotely located from the high temperature environment of the combustion chamber. A laser initiating spark generated by focusing high peak power laser light to a sufficiently tight laser spot within the fuel to cause the ionization of air and fuel into a plasma is unobtrusive to the flow dynamics of the combustion chamber of a fuel injector, thereby facilitating whatever advantage can be taken of flow dynamics in the design of the fuel injector.

Early, James W. (Los Alamos, NM); Thomas, Matthew E. (Huntsville, AL)

2001-01-01T23:59:59.000Z

302

Thermal Stabilization Blend Plan  

SciTech Connect

The Blend Plan was written to identify items stored outside of the 213 MBA that will be moved into the MBA for thermal stabilization processing. Product quality oxide items stored in our vaults are found in Appendix B. A table is included in Appendix B which details the isotopic values for the oxide items and calculates the amount of material of any specific run that can be placed in a product can and maintain the 15 watt limit to meet storage vault specifications. There is no chance of exceeding the 15 watt limit with items starting with the designations ''LAO'' or ''PBO.'' All items starting with the designations ''BO,'' ''BLO,'' and ''DZ0'' are at risk of exceeding the 15 watt specification if the can were to be filled.

RISENMAY, H.R.

1999-08-19T23:59:59.000Z

303

STABILIZED FEEDBACK AMPLIFIER  

DOE Patents (OSTI)

Negative feedback amplifiers, and particularly a negative feedback circuit which is economical on amode power consumption, are described. Basically, the disclosed circuit comprises two tetrode tubes where the output of the first tube is capacitamce coupled to the grid of the second tube, which in turn has its plate coupled to the cathode of the first tube to form a degenerative feedback circuit. Operating potential for screen of the second tube is supplied by connecting the cathode resistor of the first tube to the screen, while the screen is by-passed to the cathode of its tube for the amplified frequencies. Also, the amplifier incorporates a circuit to stabilize the transconductance of the tubes by making the grid potential of each tube interdependent on anode currents of both lubes by voltage divider circuitry.

Fishbine, H.L.; Sewell, C. Jr.

1957-08-01T23:59:59.000Z

304

Satellite Data Assimilation in Numerical Weather Prediction Models. Part II: Uses of Rain-Affected Radiances from Microwave Observations for Hurricane Vortex Analysis  

Science Conference Proceedings (OSTI)

A hybrid variational scheme (HVAR) is developed to produce the vortex analysis associated with tropical storms. This scheme allows for direct assimilation of rain-affected radiances from satellite microwave instruments. In the HVAR, the ...

Fuzhong Weng; Tong Zhu; Banghua Yan

2007-11-01T23:59:59.000Z

305

Stabilized radio-frequency quadrupole  

DOE Patents (OSTI)

A long-vane stabilized radio frequency resonator for accelerating charged particles and including means defining a radio frequency resonator cavity, a plurality of long vanes mounted in the defining means for dividing the cavity into sections, and means interconnecting opposing ones of the plurality of vanes for stabilizing the resonator.

Lancaster, H.D.; Fugitt, J.A.; Howard, D.R.

1982-09-29T23:59:59.000Z

306

Nanoscale strain-induced pair suppression as a source of vortex pinning in high-temperature superconductors  

SciTech Connect

Boosting large-scale superconductor applications require nanostructured conductors with artificial pinning centres immobilizing quantized vortices at high temperature and magnetic fields. Here we demonstrate a highly effective mechanism of artificial pinning centres in solution-derived high-temperature superconductor nanocomposites through generation of nanostrained regions where Cooper pair formation is suppressed. The nanostrained regions identified from transmission electron microscopy devise a very high concentration of partial dislocations associated with intergrowths generated between the randomly oriented nanodots and the epitaxial YBa{sub 2}Cu{sub 3}O{sub 7} matrix. Consequently, an outstanding vortex-pinning enhancement correlated to the nanostrain is demonstrated for four types of randomly oriented nanodot, and a unique evolution towards an isotropic vortex-pinning behaviour, even in the effective anisotropy, is achieved as the nanostrain turns isotropic. We suggest a new vortex-pinning mechanism based on the bond-contraction pairing model, where pair formation is quenched under tensile strain, forming new and effective core-pinning regions.

Llordes, A. [ICMAB, Barcelona, Spain; Palau, A. [ICMAB, Barcelona, Spain; Vlad, R. [ICMAB, Barcelona, Spain; Pomar, A. [ICMAB, Barcelona, Spain; Arbiol, Jordi [ICMAB, Barcelona, Spain; Guzman, Roger [ICMAB, Barcelona, Spain; Gazquez Alabart, Jaume [ORNL; Varela del Arco, Maria [ORNL; Sandiumenge, Felip [ICMAB, Barcelona, Spain; Ricart, Susagna [ICMAB, Barcelona, Spain; Puig, Teresa [ICMAB, Barcelona, Spain; Chataigner, D. [CRISMAT, Caen, France; Vanacken, J. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Gutierrez, J. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Deutscher, G. [Tel Aviv University; Moschalkov, V. [INPAC-Institute for Nanoscale Physics and Chemistry, Leuven, Belgium; Obradors, Xavier [ICMAB, Barcelona, Spain

2012-01-01T23:59:59.000Z

307

Vortex Diode Analysis and Testing for Fluoride Salt-Cooled High-Temperature Reactors  

SciTech Connect

Fluidic diodes are presently being considered for use in several fluoride salt-cooled high-temperature reactor designs. A fluidic diode is a passive device that acts as a leaky check valve. These devices are installed in emergency heat removal systems that are designed to passively remove reactor decay heat using natural circulation. The direct reactor auxiliary cooling system (DRACS) uses DRACS salt-to-salt heat exchangers (DHXs) that operate in a path parallel to the core flow. Because of this geometry, under normal operating conditions some flow bypasses the core and flows through the DHX. A flow diode, operating in reverse direction, is-used to minimize this flow when the primary coolant pumps are in operation, while allowing forward flow through the DHX under natural circulation conditions. The DRACSs reject the core decay heat to the environment under loss-of-flow accident conditions and as such are a reactor safety feature. Fluidic diodes have not previously been used in an operating reactor system, and therefore their characteristics must be quantified to ensure successful operation. This report parametrically examines multiple design parameters of a vortex-type fluidic diode to determine the size of diode needed to reject a particular amount of decay heat. Additional calculations were performed to size a scaled diode that could be tested in the Oak Ridge National Laboratory Liquid Salt Flow Loop. These parametric studies have shown that a 152.4 mm diode could be used as a test article in that facility. A design for this diode is developed, and changes to the loop that will be necessary to test the diode are discussed. Initial testing of a scaled flow diode has been carried out in a water loop. The 150 mm diode design discussed above was modified to improve performance, and the final design tested was a 171.45 mm diameter vortex diode. The results of this testing indicate that diodicities of about 20 can be obtained for diodes of this size. Experimental results show similar trends as the computational fluid dynamics (CFD) results presented in this report; however, some differences exist that will need to be assessed in future studies. The results of this testing will be used to improve the diode design to be tested in the liquid salt loop system.

Yoder Jr, Graydon L [ORNL; Elkassabgi, Yousri M. [Texas A& M University, Kingsville; De Leon, Gerardo I. [Texas A& M University, Kingsville; Fetterly, Caitlin N. [Texas A& M University, Kingsville; Ramos, Jorge A. [Texas A& M University, Kingsville; Cunningham, Richard Burns [University of Tennessee, Knoxville (UTK)

2012-02-01T23:59:59.000Z

308

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

E-Print Network (OSTI)

Liquid-metal Rankine power conversion systems (PCS) coupled with a fission reactor remain an attractive option for space power applications because system specific power and efficiency is very favorable for plant designs of 100 kW(e) or higher. Potential drawbacks to the technology in a reduced gravity environment include two-phase fluid management processes such as liquid-vapor phase separation. The most critical location for phase separation is at the boiler exit where only vapor must be sent to the turbine because blade erosion occurs from high velocity liquid droplets entrained by vapor flow. Previous studies have proposed that rotary separators be used to separate the liquid and vapor from a two phase mixture. However these devices have complex turbo machinery, require kilowatts of power and are untested for high vapor flow conditions. The Interphase Transport Phenomena (ITP) laboratory has developed a low-power, passive microgravity vortex phase separator (MVS) which has already proven to be an essential component of two-phase systems operating in low gravity environments. This thesis presents results from flight experiments where a Rankine cycle was operated in a reduced gravity environment for the first time by utilizing the MVS for liquid and vapor phase separation. The MVS was able to operate under saturated conditions and adjust to system transients as it would in the Rankine cycle by controlling the amount of liquid and vapor within the device. A new model is developed for the MVS to predict separation performance at high vapor flow conditions for sizing the separator at the boiler, condenser, and turbine locations within the cycle by using a volume limiting method. This model factors in the following separator characteristics: mass, pumping power, and available buffer volume for system transients. The study is concluded with overall Rankine efficiency and performance changes due to adding vortex phase separation and a schematic of the Rankine cycle with the integration of the MVS is presented. The results from this thesis indicate the thermal to electric efficiency and specific mass of the cycle can be improved by using the MVS to separate the two phases instead of a rotary separator.

Supak, Kevin Robert

2007-12-01T23:59:59.000Z

309

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

E-Print Network (OSTI)

Liquid-metal Rankine power conversion systems (PCS) coupled with a fission reactor remain an attractive option for space power applications because system specific power and efficiency is very favorable for plant designs of 100 kW(e) or higher. Potential drawbacks to the technology in a reduced gravity environment include two-phase fluid management processes such as liquid-vapor phase separation. The most critical location for phase separation is at the boiler exit where only vapor must be sent to the turbine because blade erosion occurs from high velocity liquid droplets entrained by vapor flow. Previous studies have proposed that rotary separators be used to separate the liquid and vapor from a two phase mixture. However these devices have complex turbo machinery, require kilowatts of power and are untested for high vapor flow conditions. The Interphase Transport Phenomena (ITP) laboratory has developed a low-power, passive microgravity vortex phase separator (MVS) which has already proven to be an essential component of two-phase systems operating in low gravity environments. This thesis presents results from flight experiments where a Rankine cycle was operated in a reduced gravity environment for the first time by utilizing the MVS for liquid and vapor phase separation. The MVS was able to operate under saturated conditions and adjust to system transients as it would in the Rankine cycle by controlling the amount of liquid and vapor within the device. A new model is developed for the MVS to predict separation performance at high vapor flow conditions for sizing the separator at the boiler, condenser, and turbine locations within the cycle by using a volume limiting method. This model factors in the following separator characteristics: mass, pumping power, and available buffer volume for system transients. The study is concluded with overall Rankine efficiency and performance changes due to adding vortex phase separation and a schematic of the Rankine cycle with the integration of the MVS is presented. The results from this thesis indicate the thermal to electric efficiency and specific mass of the cycle can be improved by using the MVS to separate the two phases instead of a rotary separator.

Supak, Kevin Robert

2007-12-01T23:59:59.000Z

310

Field investigation of keyblock stability  

SciTech Connect

Discontinuities in a rock mass can intersect an excavation surface to form discrete blocks (keyblocks) which can be unstable. This engineering problem is divided into two parts: block identification, and evaluation of block stability. One stable keyblock and thirteen fallen keyblocks were observed in field investigations at the Nevada Test Site. Nine blocks were measured in detail sufficient to allow back-analysis of their stability. Measurements included block geometry, and discontinuity roughness and compressive strength. Back-analysis correctly predicted stability or failure in all but two cases. These two exceptions involved situations that violated the stress assumptions of the stability calculations. Keyblock faces correlated well with known joint set orientations. The effect of tunnel orientation on keyblock frequency was apparent. Back-analysis of physical models successfully predicted block pullout force for two-dimensional models of unit thickness. Two-dimensional (2D) and three-dimensional (3D) analytic models for the stability of simple pyramidal keyblocks were examined. Calculated stability is greater for 3D analyses than for 2D analyses. Calculated keyblock stability increases with larger in situ stress magnitudes, larger lateral stress ratios, and larger shear strengths. Discontinuity stiffness controls block displacement more strongly than it does stability itself. Large keyblocks are less stable than small ones, and stability increases as blocks become more slender. Rock mass temperature decreases reduce the confining stress magnitudes and can lead to failure. The pattern of stresses affecting each block face explains conceptually the occurrence of pyramidal keyblocks that are truncated near their apex.

Yow, J.L. Jr.

1985-04-01T23:59:59.000Z

311

Plutonium stabilization and packaging system  

Science Conference Proceedings (OSTI)

This document describes the functional design of the Plutonium Stabilization and Packaging System (Pu SPS). The objective of this system is to stabilize and package plutonium metals and oxides of greater than 50% wt, as well as other selected isotopes, in accordance with the requirements of the DOE standard for safe storage of these materials for 50 years. This system will support completion of stabilization and packaging campaigns of the inventory at a number of affected sites before the year 2002. The package will be standard for all sites and will provide a minimum of two uncontaminated, organics free confinement barriers for the packaged material.

NONE

1996-05-01T23:59:59.000Z

312

Engineering Nanocolumnar Defect Configurations for Optimized Vortex Pinning in High Temperature Superconducting Nanocomposite Wires  

SciTech Connect

High temperature superconducting (HTS), coated conductor wires based on nanocomposite films containing self-assembled, insulating BaZrO3 (BZO) nanocolumnar defects have previously been reported to exhibit enhanced vortex pinning. Here, we report on microstructural design via control of BZO nanocolumns density in YBa2Cu3O7- (YBCO)+BZO nancomposite films to achieve the highest critical current density, Jc(H, ,T). X-ray diffraction and microstructural examination shows increasing number density of epitaxial BZO nanocolumns in the highly cube-textured YBCO matrix with increasing nominal BZO additions. Transport property measurement reveals that an increase in BZO content upto 4 vol% is required to sustain the highest pinning and Jc performance as the magnetic field increases. By growing thicker, single-layer nanocomposite films (~4 m) with controlled density of BZO columnar defects, the critical current (Ic) of ~1000 A/cm at 77 K, self-field and the minimum Ic of 455 A/cm at 65 K and 3 T for all magnetic field orientations were obtained. This is the highest Ic reported to date for films on metallic templates which are the basis for the 2nd generation, coated conductor-based HTS wires.

Wee, Sung Hun [ORNL; Zuev, Yuri L [ORNL; Cantoni, Claudia [ORNL; Goyal, Amit [ORNL; Ahuja, Raj [Waukesha Electric Systems Inc.; Abiade, J. [North Carolina A& T State University

2013-01-01T23:59:59.000Z

313

Effects of surface roughness and vortex generators on the NACA 4415 airfoil  

DOE Green Energy (OSTI)

Wind turbines in the field can be subjected to many and varying wind conditions, including high winds with rotor locked or with yaw excursions. In some cases the rotor blades may be subjected to unusually large angles of attack that possibly result in unexpected loads and deflections. To better understand loadings at unusual angles of attack, a wind tunnel test was performed. An 18-inch constant chord model of the NACA 4415 airfoil section was tested under two dimensional steady state conditions in the Ohio State University Aeronautical and Astronautical Research Laboratory (OSU/AARL) 7 x 10 Subsonic Wind Tunnel (7 x 10). The objective of these tests was to document section lift and moment characteristics under various model and air flow conditions. These included a normal angle of attack range of {minus}20{degree} to +40{degree}, an extended angle of attack range of {minus}60{degree} to +230{degree}, applications of leading edge grit roughness (LEGR), and use of vortex generators (VGs), all at chord Reynolds numbers as high as possible for the particular model configuration. To realistically satisfy these conditions the 7 x 10 offered a tunnel-height-to-model-chord ratio of 6.7, suggesting low interference effects even at the relatively high lift and drag conditions expected during the test. Significantly, it also provided chord Reynolds numbers up to 2.0 million. 167 figs., 13 tabs.

Reuss, R.L.; Hoffman, M.J.; Gregorek, G.M. [Ohio State Univ., Columbus, OH (United States)

1995-12-01T23:59:59.000Z

314

Winding numbers and scaling tilts from random vortex-antivortex pairs  

E-Print Network (OSTI)

I show that random distributions of vortex-antivortex pairs (rather than of individual vortices) lead to scaling of typical winding numbers W trapped inside a loop of circumference C with the square root of C when the expected winding numbers are large. Such scaling is consistent with the Kibble-Zurek mechanism (KZM). By contrast, distribution of individual vortices with randomly assigned topological charges would result in the dispersion of W scaling with the square root of the area inside C. Scaling of the dispersion of W and of the probability of detection of non-zero W with C can be also studied for loops so small that non-zero windings are rare. In this case I show a doubling of the scaling of dispersion with C when compared to the scaling of dispersion in the large W regime. Moreover, probability of trapping of a non-zero W becomes, in this case, proportional to the area subtended by C (hence, to the square of circumference). This quadruples, as compared with large winding numbers regime, the exponent in the power law dependence of the frequency of trapping of W=+1 or W=-1 on C. Such change of the power law exponent by a FACTOR OF FOUR implies quadrupling of the scaling of the frequency of winding number trapping with the quench rate, and is of key importance for experimental tests of KZM.

Wojciech H. Zurek

2013-05-21T23:59:59.000Z

315

Generalized Stability Theory. Part I: Autonomous Operators  

Science Conference Proceedings (OSTI)

Classical stability theory is extended to include transient growth processes. The central role of the nonnormality of the linearized dynamical system in the stability problem is emphasized, and a generalized stability theory is constructed that ...

Brian F. Farrell; Petros J. Ioannou

1996-07-01T23:59:59.000Z

316

Generalized Stability Theory. Part II: Nonautonomous Operators  

Science Conference Proceedings (OSTI)

An extension of classical stability theory to address the stability of perturbations to time-dependent systems is described. Nonnormality is found to play a central role in determining the stability of systems governed by nonautonomous operators ...

Brian F. Farrell; Petros J. Ioannou

1996-07-01T23:59:59.000Z

317

Stabilized polyacrylic saccharide protein conjugates  

DOE Patents (OSTI)

This invention is directed to water soluble protein polymer conjugates which are stabile in hostile environments. The conjugate comprises a protein which is linked to an acrylic polymer at multiple points through saccharide linker groups.

Callstrom, Matthew R. (Columbus, OH); Bednarski, Mark D. (Berkeley, CA); Gruber, Patrick R. (St. Paul, MN)

1996-01-01T23:59:59.000Z

318

Necessary conditions for stabilization agreements  

E-Print Network (OSTI)

The Climate Convention calls for stabilization of atmospheric concentrations of greenhouse gases. This paper considers the issues that must be faced in formulating a plan to meet any such target, using a proposed CO2 level ...

Yang, Zili.; Jacoby, Henry D.

319

Iodine Stabilized Helium-Neon Laser  

Science Conference Proceedings (OSTI)

... stabilized lasers or spectral lamps that have been recommended for use by international consensus. The iodine stabilized helium-neon laser is just ...

320

Radiation Stability of GFR Candidate Ceramics  

Science Conference Proceedings (OSTI)

The radiation stability of these ceramics were examined using transmission electron microscopy (TEM) to understand the effect of radiation on lattice stability,  ...

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

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

Science Conference Proceedings (OSTI)

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

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

2002-08-01T23:59:59.000Z

322

Investigation of vortex generators for augmentation of wind turbine power performance  

SciTech Connect

This study focuses on the use of vortex generators (VGs) for performance augmentation of the stall-regulated AWT-26 wind turbine. The goal was to design a VG array which would increase annual energy production (AEP) by increasing power output at moderate wind speeds, without adversely affecting the loads or stall-regulation performance of the turbine. Wind tunnel experiments were conducted at the University of Washington to evaluate the effect of VGs on the AWT-26 blade, which is lofted from National Renewable Energy Laboratory (NREL) S-series airfoils. Based on wind-tunnel results and analysis, a VG array was designed and then tested on the AWT-26 prototype, designated P1. Performance and loads data were measured for P1, both with and without VGs installed. the turbine performance with VGs met most of the design requirements; power output was increased at moderate wind speeds with a negligible effect on peak power. However, VG drag penalties caused a loss in power output for low wind speeds, such that performance with VGs resulted in a net decrease in AEP for sites having annual average wind speeds up to 8.5 m/s. While the present work did not lead to improved AEP for the AWT-2 turbine, it does provide insight into performance augmentation of wind turbines with VGs. The safe design of a VG array for a stall-regulated turbine has been demonstrated, and several issues involving optimal performance with VGs have been identified and addressed. 15 refs., 34 figs., 10 tabs.

Griffin, D.A. [Lynette (R.) and Associates, Seattle, WA (United States)

1996-12-01T23:59:59.000Z

323

Vortex induced vibration for aquatic clean power (VIVACE)NOTE FROM ACM: It has been determined that the author of this article plagiarized the contents from a previously published paper. Therefore ACM has shut off access to this paper.  

Science Conference Proceedings (OSTI)

NOTE FROM ACM: It has been determined that the author of this article plagiarized the contents from a previously published paper. Therefore ACM has shut off access to this paper. The paper by M. K. Raj and B. G. Muthuraj plagiarizes the ... Keywords: VIVACE, reynolds number, undulations, vortex shedding, vortex vibrations

M. K. Raj; B. G. Muthuraj

2011-02-01T23:59:59.000Z

324

Stability of Underwater Periodic Locomotion  

E-Print Network (OSTI)

Most aquatic vertebrates swim by lateral flapping of their bodies and caudal fins. While much effort has been devoted to understanding the flapping kinematics and its influence on the swimming efficiency, little is known about the stability (or lack of) of periodic swimming. It is believed that stability limits maneuverability and body designs/flapping motions that are adapted for stable swimming are not suitable for high maneuverability and vice versa. In this paper, we consider a simplified model of a planar elliptic body undergoing prescribed periodic heaving and pitching in potential flow. We show that periodic locomotion can be achieved due to the resulting hydrodynamic forces, and its value depends on several parameters including the aspect ratio of the body, the amplitudes and phases of the prescribed flapping. We obtain closed-form solutions for the locomotion and efficiency for small flapping amplitudes, and numerical results for finite flapping amplitudes. We then study the stability of the (finite amplitude flapping) periodic locomotion using Floquet theory. We find that stability depends nonlinearly on all parameters. Interesting trends of switching between stable and unstable motions emerge and evolve as we continuously vary the parameter values. This suggests that, for live organisms that control their flapping motion, maneuverability and stability need not be thought of as disjoint properties, rather the organism may manipulate its motion in favor of one or the other depending on the task at hand.

Fangxu Jing; Eva Kanso

2013-04-18T23:59:59.000Z

325

Propagation of an arbitrary vortex pair through an astigmatic optical system and determination of its net topological charge  

E-Print Network (OSTI)

We embed a pair of vortices with different topological charges in a Gaussian beam and study its evolution through an astigmatic optical system, a tilted lens. The propagation dynamics is explained by a closed-form analytical expression. Furthermore, we show that a careful examination of the intensity distribution at a predicted position past the lens can provide us with the net charge present in the beam. To the best of our knowledge, our method is the first non-interferometric technique to measure the net charge of an arbitrary vortex pair. Our experimental results are in close agreement with the theoretical predictions.

Reddy, Salla Gangi; Aadhi, A; Banerji, J; Singh, R P

2013-01-01T23:59:59.000Z

326

Stabilization of Nickel Metal Catalysts for Aqueous ...  

Biomass and Biofuels Stabilization of Nickel Metal Catalysts for Aqueous Processing Systems Pacific Northwest National Laboratory.

327

Nuclear structure far from stability  

E-Print Network (OSTI)

Modern nuclear structure theory is rapidly evolving towards regions of exotic short-lived nuclei far from stability, nuclear astrophysics applications, and bridging the gap between low-energy QCD and the phenomenology of finite nuclei. The principal objective is to build a consistent microscopic theoretical framework that will provide a unified description of bulk properties, nuclear excitations and reactions. Stringent constraints on the microscopic approach to nuclear dynamics, effective nuclear interactions, and nuclear energy density functionals, are obtained from studies of the structure and stability of exotic nuclei with extreme isospin values, as well as extended asymmetric nucleonic matter. Recent theoretical advances in the description of structure phenomena in exotic nuclei far from stability are reviewed.

D. Vretenar

2004-09-27T23:59:59.000Z

328

Material stabilization characterization management plan  

SciTech Connect

This document presents overall direction for characterization needs during stabilization of SNM at the Plutonium Finishing Plant (PFP). Technical issues for needed data and equipment are identified. Information on material categories and links to vulnerabilities are given. Comparison data on the material categories is discussed to assist in assessing the relative risks and desired processing priority.

GIBSON, M.W.

1999-08-31T23:59:59.000Z

329

Stability of charged thin shells  

SciTech Connect

In this article we study the mechanical stability of spherically symmetric thin shells with charge, in Einstein-Maxwell and Einstein-Born-Infeld theories. We analyze linearized perturbations preserving the symmetry, for shells around vacuum and shells surrounding noncharged black holes.

Eiroa, Ernesto F. [Instituto de Astronomia y Fisica del Espacio, C.C. 67, Suc. 28, 1428, Buenos Aires (Argentina); Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria Pab. I, 1428, Buenos Aires (Argentina); Simeone, Claudio [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria Pab. I, 1428, Buenos Aires (Argentina); IFIBA, CONICET, Ciudad Universitaria Pab. I, 1428, Buenos Aires (Argentina)

2011-05-15T23:59:59.000Z

330

Basis Document for Sludge Stabilization  

SciTech Connect

Vault personnel have begun a program of radiographing plutonium metal cans. Metal that appears to be corroded will be processed through the furnaces in Glovebox HC-21C. The fire suppression system activation temperature will be deleted because it is not maintained by PFP Stabilization.

WILKINS, N.E.

2000-04-03T23:59:59.000Z

331

Aerodynamic Drag and Gyroscopic Stability  

E-Print Network (OSTI)

This paper describes the effects on aerodynamic drag of rifle bullets as the gyroscopic stability is lowered from 1.3 to 1.0. It is well known that a bullet can tumble for stability less than 1.0. The Sierra Loading Manuals (4th and 5th Editions) have previously reported that ballistic coefficient decreases significantly as gyroscopic stability, Sg, is lowered below 1.3. These observations are further confirmed by the experiments reported here. Measured ballistic coefficients were compared with gyroscopic stabilities computed using the Miller Twist Rule for nearly solid metal bullets with uniform density and computed using the Courtney-Miller formula for plastic-tipped bullets. The experiments reported here also demonstrate a decrease in aerodynamic drag near Sg = 1.23 +/- 0.02. It is hypothesized that this decrease in drag over a narrow band of Sg values is due to a rapid damping of coning motions (precession and nutation). Observation of this drag decrease at a consistent value of Sg demonstrates the relative accuracy of the twist formulas used to compute Sg. The relationship between Sg and drag may be used to test the applicability of existing twist formulas to given bullet designs and to evaluate the accuracy of alternate formulas in cases where the existing twist formulas are not as accurate.

Elya R. Courtney; Michael W. Courtney

2013-08-15T23:59:59.000Z

332

Stability of Molten Core Materials  

SciTech Connect

The purpose of this report is to document a literature and data search for data and information pertaining to the stability of nuclear reactor molten core materials. This includes data and analysis from TMI-2 fuel and INL’s LOFT (Loss of Fluid Test) reactor project and other sources.

Layne Pincock; Wendell Hintze

2013-01-01T23:59:59.000Z

333

Magnetic Blockade Mechanism for Quantum Nucleation of Superconducting Vortex-Antivortex Pairs in Zero External Magnetic Field  

E-Print Network (OSTI)

We propose a magnetic dual of the Coulomb blockade effect for quantum nucleation of flux vortex pairs in high-Tc superconducting (HTS) films and grain boundaries in zero applied field. The magnetic blockade instability occurs at {\\theta} = {\\pi}, where {\\theta} is the "vacuum" or theta angle. The {\\theta} term has recently been discussed in the context of several other systems, including charge and spin density waves, topological insulators, the quantum Hall effect, and spontaneous CP violation. Our model predicts a sharp pair creation threshold current at {\\theta} = {\\pi}, analogous to the Coulomb blockade voltage of a tunnel junction, and explains the observed thickness dependence of critical currents in HTS coated conductors. We use the Schr\\"odinger equation to compute the evolving macrostate amplitudes, coupled by a generalized tunneling matrix element. The simulations yield excellent quantitative agreement with measured voltage-current characteristics of bi-crystal and other HTS grain boundary junctions. The model also predicts non-sinusoidal behavior in the voltage oscillations resulting from time-correlated vortex tunneling.

J. H. Miller Jr.; A. I. Wijesinghe

2011-10-12T23:59:59.000Z

334

Flame-vortex interaction and mixing behaviors of turbulent non-premixed jet flames under acoustic forcing  

SciTech Connect

This study examines the effect of acoustic excitation using forced coaxial air on the flame characteristics of turbulent hydrogen non-premixed flames. A resonance frequency was selected to acoustically excite the coaxial air jet due to its ability to effectively amplify the acoustic amplitude and reduce flame length and NO{sub x} emissions. Acoustic excitation causes the flame length to decrease by 15% and consequently, a 25% reduction in EINO{sub x} is achieved, compared to coaxial air flames without acoustic excitation at the same coaxial air to fuel velocity ratio. Moreover, acoustic excitation induces periodical fluctuation of the coaxial air velocity, thus resulting in slight fluctuation of the fuel velocity. From phase-lock PIV and OH PLIF measurement, the local flow properties at the flame surface were investigated under acoustic forcing. During flame-vortex interaction in the near field region, the entrainment velocity and the flame surface area increased locally near the vortex. This increase in flame surface area and entrainment velocity is believed to be a crucial factor in reducing flame length and NO{sub x} emission in coaxial jet flames with acoustic excitation. Local flame extinction occurred frequently when subjected to an excessive strain rate, indicating that intense mass transfer of fuel and air occurs radially inward at the flame surface. (author)

Kim, Munki; Choi, Youngil; Oh, Jeongseog; Yoon, Youngbin [School of Mechanical and Aerospace Engineering, Seoul National University, Seoul (Korea)

2009-12-15T23:59:59.000Z

335

Quantum stabilizer codes and beyond  

E-Print Network (OSTI)

The importance of quantum error correction in paving the way to build a practical quantum computer is no longer in doubt. Despite the large body of literature in quantum coding theory, many important questions, especially those centering on the issue of "good codes" are unresolved. In this dissertation the dominant underlying theme is that of constructing good quantum codes. It approaches this problem from three rather different but not exclusive strategies. Broadly, its contribution to the theory of quantum error correction is threefold. Firstly, it extends the framework of an important class of quantum codes - nonbinary stabilizer codes. It clarifies the connections of stabilizer codes to classical codes over quadratic extension fields, provides many new constructions of quantum codes, and develops further the theory of optimal quantum codes and punctured quantum codes. In particular it provides many explicit constructions of stabilizer codes, most notably it simplifies the criteria by which quantum BCH codes can be constructed from classical codes. Secondly, it contributes to the theory of operator quantum error correcting codes also called as subsystem codes. These codes are expected to have efficient error recovery schemes than stabilizer codes. Prior to our work however, systematic methods to construct these codes were few and it was not clear how to fairly compare them with other classes of quantum codes. This dissertation develops a framework for study and analysis of subsystem codes using character theoretic methods. In particular, this work established a close link between subsystem codes and classical codes and it became clear that the subsystem codes can be constructed from arbitrary classical codes. Thirdly, it seeks to exploit the knowledge of noise to design efficient quantum codes and considers more realistic channels than the commonly studied depolarizing channel. It gives systematic constructions of asymmetric quantum stabilizer codes that exploit the asymmetry of errors in certain quantum channels. This approach is based on a Calderbank- Shor-Steane construction that combines BCH and finite geometry LDPC codes.

Sarvepalli, Pradeep Kiran

2008-08-01T23:59:59.000Z

336

Capacity Markets and Market Stability  

Science Conference Proceedings (OSTI)

The good news is that market stability can be achieved through a combination of longer-term contracts, auctions for far enough in the future to permit new entry, a capacity management system, and a demand curve. The bad news is that if and when stable capacity markets are designed, the markets may seem to be relatively close to where we started - with integrated resource planning. Market ideologues will find this anathema. (author)

Stauffer, Hoff

2006-04-15T23:59:59.000Z

337

Mercury Stability in FGD Byproducts  

Science Conference Proceedings (OSTI)

A significant fraction of the mercury in coals fired for power generation currently is removed by wet flue gas desulfurization (FGD) systems and incorporated in the byproducts from those systems. This report summarizes the results of an EPRI-sponsored project to measure the stability of mercury in FGD byproducts from coal-fired generating plants under simulated landfill and reuse conditions. The current effort repeated portions of a 2003 project, documented in EPRI report 1004254, to determine whether th...

2004-03-24T23:59:59.000Z

338

On the stability of stationary age distributions  

Science Conference Proceedings (OSTI)

Age structured nonlinear single species and predator prey population models are treated and a straightforward relatively simple method is shown to arrive at a condition of stability of stationary solutions. Keywords: population dynamics, stability

M. Farkas

2002-09-01T23:59:59.000Z

339

On Stability of Cellular Neural Networks  

Science Conference Proceedings (OSTI)

The main results about stability of cellular neural networks (CNNs) are reviewed. Some of them are extended and reformulated, with the purpose of providing to the CNN designer simple criteria for checking the stability properties. A particular emphasis ...

Pier Paolo-Civalleri; Marco Gilli

1999-11-01T23:59:59.000Z

340

Stabilization of Graphene-Polyaniline Based Nanocomposite ...  

Science Conference Proceedings (OSTI)

Presentation Title, Stabilization of Graphene-Polyaniline Based Nanocomposite Electrodes Using Barium Strontium Titanate for Supercapacitor Application.

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

PHASE TRANSFORMATIONS, STABILITY AND MATERIALS INTERACTIONS  

E-Print Network (OSTI)

transport, surface energies, matrix structure. C. Hydrogen-energy save. •Fiber reinforced polymers -Stability of polymer matrix (

Morris, Jr., J.W.

2010-01-01T23:59:59.000Z

342

High-Compression-Ratio; Atkinson-Cycle Engine Using Low-Pressure Direct Injection and Pneumatic-Electronic Valve Actuation Enabled by Ionization Current and Foward-Backward Mass Air Flow Sensor Feedback  

DOE Green Energy (OSTI)

This report describes the work completed over a two and one half year effort sponsored by the US Department of Energy. The goal was to demonstrate the technology needed to produce a highly efficient engine enabled by several technologies which were to be developed in the course of the work. The technologies included: (1) A low-pressure direct injection system; (2) A mass air flow sensor which would measure the net airflow into the engine on a per cycle basis; (3) A feedback control system enabled by measuring ionization current signals from the spark plug gap; and (4) An infinitely variable cam actuation system based on a pneumatic-hydraulic valve actuation These developments were supplemented by the use of advanced large eddy simulations as well as evaluations of fuel air mixing using the KIVA and WAVE models. The simulations were accompanied by experimental verification when possible. In this effort a solid base has been established for continued development of the advanced engine concepts originally proposed. Due to problems with the valve actuation system a complete demonstration of the engine concept originally proposed was not possible. Some of the highlights that were accomplished during this effort are: (1) A forward-backward mass air flow sensor has been developed and a patent application for the device has been submitted. We are optimistic that this technology will have a particular application in variable valve timing direct injection systems for IC engines. (2) The biggest effort on this project has involved the development of the pneumatic-hydraulic valve actuation system. This system was originally purchased from Cargine, a Swedish supplier and is in the development stage. To date we have not been able to use the actuators to control the exhaust valves, although the actuators have been successfully employed to control the intake valves. The reason for this is the additional complication associated with variable back pressure on the exhaust valves when they are opened. As a result of this effort, we have devised a new design and have filed for a patent on a method of control which is believed to overcome this problem. The engine we have been working with originally had a single camshaft which controlled both the intake and exhaust valves. Single cycle lift and timing control was demonstrated with this system. (3) Large eddy simulations and KIVA based simulations were used in conjunction with flow visualizations in an optical engine to study fuel air mixing. During this effort we have devised a metric for quantifying fuel distribution and it is described in several of our papers. (4) A control system has been developed to enable us to test the benefits of the various technologies. This system used is based on Opal-RT hardware and is being used in a current DOE sponsored program.

Harold Schock; Farhad Jaberi; Ahmed Naguib; Guoming Zhu; David Hung

2007-12-31T23:59:59.000Z

343

Stability issues for dynamic traffic assignment  

Science Conference Proceedings (OSTI)

This paper explores stability issues for operational route guidance control strategies for vehicular traffic networks equipped with advanced information systems, and develops a general procedure for the stability analysis of the associated dynamic traffic ... Keywords: Dynamical systems, Feedback control, Lyapunov methods, Stability analysis

S. Peeta; T. -H. Yang

2003-01-01T23:59:59.000Z

344

Voltage Stability Studies for Southern Company Services  

Science Conference Proceedings (OSTI)

This report describes a study conducted under an EPRI Tailored Collaboration project to develop and demonstrate procedures for the assessment of voltage security of the Southern Electric System (SES). The contractor used EPRI steady-state analysis tools including VSTAB (Voltage STABility assessment program) to assess stability margins and verified them using EPRI dynamic tools including ETMSP (Extended Transient / Mid-term Stability Program).

1997-12-31T23:59:59.000Z

345

A Stability of LCLS Linac Modulators  

SciTech Connect

Information concerning to a stability of LCLS RF linac modulators is allocated in this paper. In general a 'pulse-to-pulse' modulator stability (and RF phase as well) is acceptable for the LCLS commission and FEL programs. Further modulator stability improvements are possible and approaches are discussed based on our experimental results.

Decker, F.-J.; Krasnykh, A.; Morris, B.; Nguyen, M.; /SLAC

2012-06-13T23:59:59.000Z

346

An investigation of the Goshen County, Wyoming, tornadic supercell of 5 June 2009 using EnKF assimilation of mobile mesonet and radar observations collected during VORTEX2. Part I: Experiment design and verification of the EnKF analyses  

Science Conference Proceedings (OSTI)

High-resolution Doppler radar velocities and in situ surface observations collected in a tornadic supercell on 5 June 2009 during the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) are assimilated into a simulated ...

James Marquis; Yvette Richardson; Paul Markowski; David Dowell; Joshua Wurman; Karen Kosiba; Paul Robinson; Glen Romine

347

Lean Premixed Flame Stability Investigations  

E-Print Network (OSTI)

Fellowship Experience Throughout my twelve-week fellowship at Pratt & Whitney I had the opportunity to interact with numerous engineers and managers as well as to be exposed to a variety of disciplines and areas of engineering. My mentor, Bill Proscia, is an expert in the field of combustion instability analysis and modeling. I gained valuable experience working on a combustion project under his guidance. The project involved studying combustor aerodynamics and static stability of lean-premixed flames for two combustor geometries as a function of swirl number and fuel type. Having an almost non-existent background in the field of combustion, this was a challenging, but very rewarding project to work on. The first few weeks consisted of meeting with engineers and managers to decide on what kind of study I could conduct that would be useful to Pratt & Whitney. During this time I also was able to learn about the business side of engineering and gain a small insight into the overall infrastructure of Pratt & Whitney. In addition to these meetings much of my time was spent reading published literature as well as textbooks on combustion, methods used for modeling combustion, combustion stability, and other

Jared Crosby

2005-01-01T23:59:59.000Z

348

The influence of vortex pinning and grain boundary structure on critical currents across grain boundaries in YBa{sub 2}Cu{sub 3}O{sub x}.  

SciTech Connect

We have used studies of single grain boundaries in YBCO thin films and bulk bicrystals to study the influence of vortex pinning along a grain boundary on dissipation. The critical current density for transport across grain boundaries in thin films is typically more than an order of magnitude larger than that measured for transport across grain boundaries in bulk samples. For low disorientation angles, the difference in critical current density within the grains that form the boundary can contribute to the substantial differences in current density measured across the boundary. However, substantial differences exist in the critical current density across boundaries in thin film compared to bulk bicrystals even in the higher angle regime in which grain boundary dissipation dominates. The differences in critical current density in this regime can be understood on the basis of vortex pinning along the boundary.

Miller, D. J.

1998-10-27T23:59:59.000Z

349

Comparative Study of Vibration Stability at Operating Light Source Facilities and Lessons Learned in Achieving NSLS II Stability Goals  

E-Print Network (OSTI)

Comparative Study of Vibration Stability at Operating Light Source Facilities and Lessons Learned in Achieving NSLS II Stability Goals

Simos, N; Fallier, M

2008-01-01T23:59:59.000Z

350

Surface rheology and interface stability.  

SciTech Connect

We have developed a mature laboratory at Sandia to measure interfacial rheology, using a combination of home-built, commercially available, and customized commercial tools. An Interfacial Shear Rheometer (KSV ISR-400) was modified and the software improved to increase sensitivity and reliability. Another shear rheometer, a TA Instruments AR-G2, was equipped with a du Nouey ring, bicone geometry, and a double wall ring. These interfacial attachments were compared to each other and to the ISR. The best results with the AR-G2 were obtained with the du Nouey ring. A Micro-Interfacial Rheometer (MIR) was developed in house to obtain the much higher sensitivity given by a smaller probe. However, it was found to be difficult to apply this technique for highly elastic surfaces. Interfaces also exhibit dilatational rheology when the interface changes area, such as occurs when bubbles grow or shrink. To measure this rheological response we developed a Surface Dilatational Rheometer (SDR), in which changes in surface tension with surface area are measured during the oscillation of the volume of a pendant drop or bubble. All instruments were tested with various surfactant solutions to determine the limitations of each. In addition, foaming capability and foam stability were tested and compared with the rheology data. It was found that there was no clear correlation of surface rheology with foaming/defoaming with different types of surfactants, but, within a family of surfactants, rheology could predict the foam stability. Diffusion of surfactants to the interface and the behavior of polyelectrolytes were two subjects studied with the new equipment. Finally, surface rheological terms were added to a finite element Navier-Stokes solver and preliminary testing of the code completed. Recommendations for improved implementation were given. When completed we plan to use the computations to better interpret the experimental data and account for the effects of the underlying bulk fluid.

Yaklin, Melissa A.; Cote, Raymond O.; Moffat, Harry K.; Grillet, Anne Mary; Walker, Lynn; Koehler, Timothy P.; Reichert, Matthew D. (Carnegie Mellon University, Pittsburgh, PA); Castaneda, Jaime N.; Mondy, Lisa Ann; Brooks, Carlton, F.

2010-11-01T23:59:59.000Z

351

STABILIZED HIGH INTENSITY SOURCE OF 80 kv  

SciTech Connect

With the change of the current load from 0 to 2.5 mamp and simultaneous change of incoming intensity from 270 to 190 v, the stabilized high-intensity source changes less than l%.. The stabilized intensity can be arranged in steps of 5 kv from 60 to 80 kv. The high-intensity stabilizer automatically switches on upon reaching 60 kv. (tr-auth)

Polivanov, V.V.; Izyurov, A.V.; Pyatakov, N.I.

1959-09-01T23:59:59.000Z

352

Rocky Flats ash test procedure (sludge stabilization)  

SciTech Connect

Rocky Flats Ash items have been identified as the next set of materials to be stabilized. This test is being run to determine charge sizes and soak times to completely stabilize the Rocky Flats Ash items. The information gathered will be used to generate the heating rampup cycle for stabilization. This test will also gain information on the effects of the glovebox atmosphere (moisture) on the stabilized material. This document provides instructions for testing Rocky Flats Ash in the HC-21C muffle furnace process.

Winstead, M.L.

1995-09-14T23:59:59.000Z

353

Thermochemical Stability of Blue Ceramic Powders  

Science Conference Proceedings (OSTI)

Abstract Scope, This paper presents the thermo-chemical stability of diverse ... Hydraulic Simulation of Fluid Flow in Beam Blank Continuous Casting Mold with

354

Precursor Compositions and Stabilization Methods for ...  

Precursor Compositions and Stabilization Methods for Polyolefin-Based Carbon Fiber Manufacturing Note: The technology described above is an early stage opportunity.

355

Manpower Training Programs and Employment Stability  

E-Print Network (OSTI)

Evaluations of Training Programs with Experimental Data,MANPOWER TRAINING PROGRAMS AND EMPLOYMENT STABILITY by JosefS44 and JO548-SOZ. Manpower training programs and employment

Zweimuller, Josef; Winter- Ebmer, Rudolf

1992-01-01T23:59:59.000Z

356

System design description PFP thermal stabilization  

SciTech Connect

The purpose of this document is to provide a system design description and design basis for the Plutonium Finishing P1ant (PFP) Thermal Stabilization project. The sources of material for this project are residues scraped from glovebox floors and materials already stored in vault storage that need further stabilizing to meet the 3013 storage requirements. Stabilizing this material will promote long term storage and reduced worker exposure. This document addresses: function design, equipment, and safety requirements for thermal stabilization of plutonium residues and oxides.

RISENMAY, H.R.

1998-11-10T23:59:59.000Z

357

Phase Stability, Phase Transformations, and Reactive Phase ...  

Science Conference Proceedings (OSTI)

Jul 31, 2012 ... New Phase in Stoichiometric Cu6Sn5 and Effect of Ni Addition on Phase Stabilization in Wide Temperature Range · Optical Properties of ...

358

Stability of Java interfaces: a preliminary investigation  

Science Conference Proceedings (OSTI)

The attribute of stability is regarded by some as an important attribute of software. Some claims regarding software design quality imply that what are called interfaces in Java are stable. This paper introduces some new metrics for investigating ... Keywords: java interface, software metrics, stability

Jonathan Chow; Ewan Tempero

2011-05-01T23:59:59.000Z

359

Quantifying Dynamic Stability of Genetic Memory Circuits  

Science Conference Proceedings (OSTI)

Bistability/Multistability has been found in many biological systems including genetic memory circuits. Proper characterization of system stability helps to understand biological functions and has potential applications in fields such as synthetic biology. ... Keywords: Dynamic stability, genetic memory, gene circuit, dynamic noise margin.

Yong Zhang; Peng Li; Garng Huang

2012-05-01T23:59:59.000Z

360

Stability analysis of switched linear singular systems  

Science Conference Proceedings (OSTI)

This paper addresses the stability analysis problem for switched linear continuous-time singular systems. First, based on the equivalent dynamics decomposition form, a refined description for state jumps of the switched singular system is presented, ... Keywords: Average dwell time, Exponential stability, State jumps, Switched singular systems

Lei Zhou, Daniel W. C. Ho, Guisheng Zhai

2013-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

KSTABILITY AND PARABOLIC STABILITY YANN ROLLIN  

E-Print Network (OSTI)

K­STABILITY AND PARABOLIC STABILITY YANN ROLLIN Abstract. Parabolic structures with rational that the three notions of parabolic polystability, K­polystability and existence of constant sca­ lar curvature K, we study iterated blowups of ruled surfaces encoded by a parabolic structure. Our main result, stated

Paris-Sud XI, Université de

362

Pipe crawler with stabilizing midsection  

DOE Patents (OSTI)

A pipe crawler is described having a midsection that provides the stability and flexibility to allow the pipe crawler to negotiate curved and uneven segments of piping while traveling through piping systems. The pipe crawler comprises a front leg assembly, a rear leg assembly, a midsection with a gimbal at each end for connecting the midsection to the front and rear leg assemblies in a flexible manner, and an air cylinder for changing the distance between the front and rear leg assemblies. The pipe crawler moves in ''inch worm'' fashion with the front and rear leg assemblies alternating between an extended and a retracted position as the air cylinder moves the retracted leg assembly forward. The midsection has a plurality of legs extending radially for holding the midsection within a maximum displacement from the piping axis so that the gimbals are not pivoted to extreme angles where they might lock up or seize. When the midsection is displaced sufficiently, its legs with wheels on each end engage the interior surface of the piping and prevent further displacement. Using two gimbals divides the angle between the planes defined by the front and rear leg assemblies which also helps to prevent excessive gimbal pivoting. 5 figures.

Zollinger, W.T.; Treanor, R.C.

1994-12-27T23:59:59.000Z

363

Irradiation Stability of Carbon Nanotubes  

E-Print Network (OSTI)

Ion irradiation of carbon nanotubes is a tool that can be used to achieve modification of the structure. Irradiation stability of carbon nanotubes was studied by ion and electron bombardment of the samples. Different ion species at various energies were used in experiments, and several defect characterization techniques were applied to characterize the damage. Development of dimensional changes of carbon nanotubes in microscopes operated at accelerating voltages of 30 keV revealed that binding energy of carbon atoms in CNs is much lower than in bulk materials. Resistivity measurements during irradiation demonstrated existence of a quasi state of defect creation. Linear relationship between ID/IG ratio and increasing irradiation fluence was revealed by Raman spectroscopy study of irradiated carbon buckypapers. The deviations from linear relationship were observed for the samples irradiated to very high fluence values. Annealing of irradiated samples was able to reduce the value of ID/IG ratio and remove defects. However, annealing could not affect ID/IG ratio and remove defects in amorphized samples. The extracted value of activation energy for irradiated sample was 0.36 ±0.05 eV. The value of activation energy was in good agreement with theoretical studies.

Aitkaliyeva, Assel

2009-08-01T23:59:59.000Z

364

Definition: Stability Limit | Open Energy Information  

Open Energy Info (EERE)

Limit Limit Jump to: navigation, search Dictionary.png Stability Limit The maximum power flow possible through some particular point in the system while maintaining stability in the entire system or the part of the system to which the stability limit refers.[1] Related Terms power, system, stability References ↑ Glossary of Terms Used in Reliability Standards An in LikeLike UnlikeLike You like this.Sign Up to see what your friends like. line Glossary Definition Retrieved from "http://en.openei.org/w/index.php?title=Definition:Stability_Limit&oldid=480505" Categories: Definitions ISGAN Definitions What links here Related changes Special pages Printable version Permanent link Browse properties 429 Throttled (bot load) Error 429 Throttled (bot load) Throttled (bot load)

365

Laser stabilization using spectral hole burning  

E-Print Network (OSTI)

We have frequency stabilized a Coherent CR699-21 dye laser to a transient spectral hole on the 606 nm transition in Pr^{+3}:Y_2SiO_5. A frequency stability of 1 kHz has been obtained on the 10 microsecond timescale together with a long-term frequency drift below 1 kHz/s. RF magnetic fields are used to repopulate the hyperfine levels allowing us to control the dynamics of the spectral hole. A detailed theory of the atomic response to laser frequency errors has been developed which allows us to design and optimize the laser stabilization feedback loop, and specifically we give a stability criterion that must be fulfilled in order to obtain very low drift rates. The laser stability is sufficient for performing quantum gate experiments in Pr^{+3}:Y_2SiO_5.

L. Rippe; B. Julsgaard; A. Walther; S. Kröll

2006-11-05T23:59:59.000Z

366

Process for stabilization of coal liquid fractions  

SciTech Connect

Coal liquid fractions to be used as fuels are stabilized against gum formation and viscosity increases during storage, permitting the fuel to be burned as is, without further expensive treatments to remove gums or gum-forming materials. Stabilization is accomplished by addition of cyclohexanol or other simple inexpensive secondary and tertiary alcohols, secondary and tertiary amines, and ketones to such coal liquids at levels of 5-25% by weight with respect to the coal liquid being treated. Cyclohexanol is a particularly effective and cost-efficient stabilizer. Other stabilizers are isopropanol, diphenylmethanol, tertiary butanol, dipropylamine, triethylamine, diphenylamine, ethylmethylketone, cyclohexanone, methylphenylketone, and benzophenone. Experimental data indicate that stabilization is achieved by breaking hydrogen bonds between phenols in the coal liquid, thereby preventing or retarding oxidative coupling. In addition, it has been found that coal liquid fractions stabilized according to the invention can be mixed with petroleum-derived liquid fuels to produce mixtures in which gum deposition is prevented or reduced relative to similar mixtures not containing stabilizer.

Davies, Geoffrey (Boston, MA); El-Toukhy, Ahmed (Alexandria, EG)

1987-01-01T23:59:59.000Z

367

Stability estimates in stationary inverse transport  

E-Print Network (OSTI)

We study the stability of the reconstruction of the scattering and absorption coefficients in a stationary linear transport equation from knowledge of the full albedo operator in dimension $n\\geq3$. The albedo operator is defined as the mapping from the incoming boundary conditions to the outgoing transport solution at the boundary of a compact and convex domain. The uniqueness of the reconstruction was proved in [M. Choulli-P. Stefanov, 1996 and 1999] and partial stability estimates were obtained in [J.-N. Wang, 1999] for spatially independent scattering coefficients. We generalize these results and prove an $L^1$-stability estimate for spatially dependent scattering coefficients.

Guillaume Bal; Alexandre Jollivet

2008-04-08T23:59:59.000Z

368

Long life lithium batteries with stabilized electrodes  

DOE Patents (OSTI)

The present invention relates to non-aqueous electrolytes having electrode stabilizing additives, stabilized electrodes, and electrochemical devices containing the same. Thus the present invention provides electrolytes containing an alkali metal salt, a polar aprotic solvent, and an electrode stabilizing additive. In some embodiments the additives include a substituted or unsubstituted cyclic or spirocyclic hydrocarbon containing at least one oxygen atom and at least one alkenyl or alkynyl group. When used in electrochemical devices with, e.g., lithium manganese oxide spinel electrodes or olivine or carbon-coated olivine electrodes, the new electrolytes provide batteries with improved calendar and cycle life.

Amine, Khalil (Downers Grove, IL); Liu, Jun (Naperville, IL); Vissers, Donald R. (Naperville, IL); Lu, Wenquan (Darien, IL)

2009-03-24T23:59:59.000Z

369

Flame stabilizer for stagnation flow reactor  

DOE Patents (OSTI)

A method of stabilizing a strained flame in a stagnation flow reactor. By causing a highly strained flame to be divided into a large number of equal size segments it is possible to stablize a highly strained flame that is on the verge of extinction, thereby providing for higher film growth rates. The flame stabilizer is an annular ring mounted coaxially and coplanar with the substrate upon which the film is growing and having a number of vertical pillars mounted on the top surface, thereby increasing the number of azimuthal nodes into which the flame is divided and preserving an axisymmetric structure necessary for stability.

Hahn, David W. (Dublin, CA); Edwards, Christopher F. (Sunnyvale, CA)

1999-01-01T23:59:59.000Z

370

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

SciTech Connect

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

Manohar S. Sohal

2005-09-01T23:59:59.000Z

371

Tennessee Electrical Contractor Witnesses Stabilization | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Tennessee Electrical Contractor Witnesses Stabilization Tennessee Electrical Contractor Witnesses Stabilization Tennessee Electrical Contractor Witnesses Stabilization April 2, 2010 - 11:31am Addthis Joshua DeLung David Andrews of Andrews AC Electric Inc., in Knoxville, Tenn., is one example of the small business owners who have flooded the state's Department of Human Services with positive feedback. David has seen his business go from layoffs to stabilization. As the economy has strengthened, so has his company. The DHS is responsible for awarding Recovery Act weatherization funding in Tennessee from the U.S. Department of Energy, and the effects of weatherization work in the Volunteer State are helping small businesses like David's prosper. "The weatherization contracts have helped us, and I have been able to

372

TRUCK ROLL STABILITY DATA COLLECTION AND ANALYSIS  

NLE Websites -- All DOE Office Websites (Extended Search)

16 TRUCK ROLL STABILITY DATA COLLECTION AND ANALYSIS S. S. Stevens, Principal Investigator S. M. Chin K. A. Hake H. L. Hwang J. P. Rollow L. F. Truett July 2001 Prepared for the...

373

PHASE TRANSFORMATIONS, STABILITY AND MATERIALS INTERACTIONS  

E-Print Network (OSTI)

IV); Fuel stability *(N) Fossil Energy Complex Spec. ComplexInteraction 11-2 Fossil Energy Chairman: R. Jaffee Members:that programming in fossil energy research supported by the

Morris, Jr., J.W.

2010-01-01T23:59:59.000Z

374

Stability of alert survivable forces during reductions  

Science Conference Proceedings (OSTI)

The stability of current and projected strategic forces are discussed within a framework that contains elements of current US and Russian analyses. For current force levels and high alert, stability levels are high, as are the levels of potential strikes, due to the large forces deployed. As force levels drop towards those of current value target sets, the analysis becomes linear, concern shifts from stability to reconstitution, and survivable forces drop out. Adverse marginal costs generally provide disincentives for the reduction of vulnerable weapons, but the exchange of vulnerable for survivable weapons could reduce cost while increasing stability even for aggressive participants. Exchanges between effective vulnerable and survivable missile forces are studied with an aggregated, probabilistic model, which optimizes each sides` first and determines each sides` second strikes and costs by minimizing first strike costs.

Canavan, G.H.

1998-01-01T23:59:59.000Z

375

Stabilizers for oil slurries of carbonaceous material  

SciTech Connect

Slurries of carbonaceous material in oil, particularly coal, are stabilized with particular tertiary amines. An example is tallow amine first condensed with two moles of propylene oxide and then condensed with thirteen moles of ethylene oxide.

Schick, M. J.

1985-01-08T23:59:59.000Z

376

Linear Stability Models of Shelfbreak Fronts  

Science Conference Proceedings (OSTI)

The stability of inviscid frontally trapped waves along a shelfbreak is examined to determine whether frontal instabilities may contribute to the alongfront variability frequently observed. Three different basic states with increasingly complex ...

Glen Gawarkiewicz

1991-04-01T23:59:59.000Z

377

What does stabilizing greenhouse gas concentrations mean?  

E-Print Network (OSTI)

The MIT Emissions Prediction and Policy Analysis (EPPA) model is applied to an exploration of the national emissions obligations that would be required to stabilize atmospheric CO2 concentrations at levels now under active ...

Jacoby, Henry D.; Schmalensee, Richard.; Reiner, David M.

378

Spirals in Potential Vorticity. Part II: Stability  

Science Conference Proceedings (OSTI)

A model of the linear stability of spiral-shaped potential vorticity (PV) filaments is constructed by using the Kolmogorov capacity as a time-independent characterization of their structure, assuming that the dynamics is essentially barotropic. ...

John Methven

1998-06-01T23:59:59.000Z

379

Linear Stability of Modons on a Sphere  

Science Conference Proceedings (OSTI)

The linear stability of two stationary dipolar modon solutions of the nondivergent barotropic vorticity equation on a rotating sphere is investigated. A numerical normal mode analysis of the linearized equation is performed by solving the ...

E. C. Neven

2001-08-01T23:59:59.000Z

380

Vortex Solutions and a Novel Role for R-parity in an N=2-Supersymmetric Model for Graphene  

E-Print Network (OSTI)

In a previous work, we have been able to settle Jackiw's et al. chiral gauge theory for Dirac fermions in graphene in an N=1 supersymmetric framework, using a tau3-QED prescription, defined by means of a single pair of gauge charged superfields, but without preserving a global phase symmetry associated to the electric charge. In the present work, we propose another N=1-generalisation which indeed preserves this symmetry, namely, a straightforward extension built upon a set of two pairs of (chiral) gauge-charged superfields plus an extra pair of electrically neutral superfields. We then further proceed to establish, via a dimensional reduction procedure, an N=2 extension, allowing for the identification of non-perturbative features, as we put forward Bogomol'nyi equations and obtain vortex-like solutions saturating a topologically non-trivial bound. Remarkably, the bosonic projection of the N=2 functional space onto the saturated regime analysed herewith reveals to be free from extra scalar degrees of freedom that would otherwise demand a phenomenological interpretation. The investigation of Jackiw's model within an N=2 complex superspace is also motivated by the assumption that an R-parity-like symmetry could provide a route to incorporate the global phase-fermion number invariance as an external-like symmetry of the theory, thus associating the electric charge in graphene to the complex covariance (super-)space for the N=2-D=3 setup. We prove such a hypothesis to be realisable, as we build up the model endowed with all the symmetries required to further extend Jackiw's chiral gauge theory.

Everton M. C. Abreu; Marco A. De Andrade; Leonardo P. G. De Assis; José A. Helayël-Neto; A. L. M. A. Nogueira; Ricardo C. Paschoal

2013-08-09T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Stabilizing windings for tilting and shifting modes  

DOE Patents (OSTI)

This invention relates to passive conducting loops for stabilizing a plasma ring against unstable tilting and/or shifting modes. To this end, for example, plasma ring in a spheromak is stabilized by a set of four figure-8 shaped loops having one pair on one side of the plasma and one pair on the other side with each pair comprising two loops whose axes are transverse to each other.

Jardin, Stephen C. (Princeton, NJ); Christensen, Uffe R. (Princeton, NJ)

1984-01-01T23:59:59.000Z

382

Stabilized fuel with silica support structure  

DOE Patents (OSTI)

This report describes a stabilized fuel which is supported by a silica support structure. The silica support structure provides a low density, high porosity vehicle for safely carrying hydrocarbon fuels. The silica support structure for hydrocarbon fuel does not produce toxic material residues on combustion which would pose environmentally sensitive disposal problems. The silica stabilized fuel composition is useful as a low temperature, continuous burning fire starter for wood or charcoal.

Poco, J.F.; Hrubesh, L.W.

1991-12-31T23:59:59.000Z

383

Turbine blade platform film cooling with simulated stator-rotor purge flow with varied seal width and upstream wake with vortex  

E-Print Network (OSTI)

The turbine blade platform can be protected from hot mainstream gases by injecting cooler air through the gap between stator and rotor. The effectiveness of this film cooling method depends on the geometry of the slot, the quantity of injected air, and the secondary flows near the platform. The purpose of this study was to measure the effect of the upstream vane or stator on this type of platform cooling, as well as the effect of changes in the width of the gap. Film cooling effectiveness distributions were obtained on a turbine blade platform within a linear cascade with upstream slot injection. The width of the slot was varied as well as the mass flow rate of the injected coolant. Obstacles were placed upstream to model the effect of the upstream vane. The coolant was injected through an advanced labyrinth seal to simulate purge flow through a stator-rotor seal. The width of the opening of this seal was varied to simulate the effect of misalignment. Stationary rods were placed upstream of the cascade in four phase locations to model the unsteady wake formed at the trailing edge of the upstream vane. Delta wings were also placed in four positions to create a vortex similar to the passage vortex at the exit of the vane. The film cooling effectiveness distributions were measured using pressure-sensitive paint (PSP). Reducing the width of the slot was found to decrease the area of coolant coverage, although the film cooling effectiveness close to the slot was slightly increased. The unsteady wake was found to have a trivial effect on platform cooling, while the passage vortex from the upstream vane may significantly reduce the film cooling effectiveness.

Blake, Sarah Anne

2007-05-01T23:59:59.000Z

384

Effects of buoyancy on premixed flame stabilization  

Science Conference Proceedings (OSTI)

The stabilization limits of v-flame and conical flames are investigated in normal gravity (+g) and reversed gravity (up-side-down burner, -g) to compare with observations of flame stabilization during microgravity experiments. The results show that buoyancy has most influence on the stabilization of laminar V-flames. Under turbulent conditions, the effects are less significant. For conical flames stabilized with a ring, the stabilization domain of the +g and -g cases are not significantly different. Under reversed gravity, both laminar v-flames and conical flames show flame behaviors that were also found in microgravity. The v-flames reattached to the rim and the conical flame assumed a top-hat shape. One of the special cases of -g conical flame is the buoyancy stabilized laminar flat flame that is detached from the burner. These flame implies a balance between the flow momentum and buoyant forces. The stretch rates of these flames are sufficiently low (laminar burning speed S{sub L}{sup 0}. An analysis based on evaluating the Richardson number is used to determine the relevant parameters that describe the buoyancy/momentum balance. A perfect balance i.e. Ri = l can be attained when the effect of heat loss from the flame zone is low. For the weaker lean cases, our assumption of adiabaticity tends to overestimate the real flame temperature. This interesting low stretch laminar flame configuration can be useful for fundamental studies of combustion chemistry.

Bedat, B.; Cheng, R.K.

1995-10-01T23:59:59.000Z

385

Cavity-stabilized laser with acceleration sensitivity below 10 g  

Science Conference Proceedings (OSTI)

... Typically, lasers for such applications are stabilized by locking them to a Fabry-Pérot cavity such that the fractional frequency stability of the laser is ...

2013-04-02T23:59:59.000Z

386

Stabilization Strategies of the Lumbar Spine in Vivo.  

E-Print Network (OSTI)

??In developing a method of quantifying stability in the lumbar spine Cholewicki and McGill (1996) have also broached the notion of sufficient stability, where too… (more)

Grenier, Sylvain

2006-01-01T23:59:59.000Z

387

Load Control for System Reliability and Measurement-Based Stability...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Load Control for System Reliability and Measurement-Based Stability Assessment Load Control for System Reliability and Measurement-Based Stability Assessment Research and develop...

388

Analysis of Lipid OxidationChapter 9 Accelerated Stability Tests  

Science Conference Proceedings (OSTI)

Analysis of Lipid Oxidation Chapter 9 Accelerated Stability Tests Methods and Analyses eChapters Methods - Analyses Books Downloadable pdf of Chapter 9 Accelerated Stability Tests from ...

389

Comprehensive Stability Analysis using Synchrophasors: Stability Assessment and Control from Synchrophasor Data  

Science Conference Proceedings (OSTI)

Power system stability is the ability of an electric power system to regain a state of operating equilibrium after being subjected to a physical disturbance. To maintain power system reliability, it is essential that operators ensure satisfactory rotor angle and voltage stability performance under anticipated operating scenarios and contingency conditions.Stability assessment has been dominated by simulation-based approach, in which off-line simulations are conducted to evaluate rotor ...

2013-12-09T23:59:59.000Z

390

High Performance Computing for Stability Problems - Applications to Hydrodynamic Stability and Neutron Transport Criticality.  

E-Print Network (OSTI)

??In this work we examine two kinds of applications in terms of stability and perform numerical evaluations and benchmarks on parallel platforms. We consider the… (more)

Subramanian, Chandramowli

2011-01-01T23:59:59.000Z

391

Thermal stabilization FY 1999 blend plan  

SciTech Connect

This Blend Plan documents the alternate feed material items for the thermal stabilization process that will be used in place of the metal items that were originally planned to be processed. Problems with resolution of the safety basis for the metal items resulted in the decision to run material that already had an established safety basis. Various in process and scrap recovery items stored in gloveboxes, plutonium oxide and plutonium oxide mixed with uranium oxide stored in 2736-2 vaults will be processed through the stabilization furnaces until the safety basis for the metal items has been resolved. The purpose of thermal stabilization is to heat the material to 1000 degrees Celsius to drive off all volatile materials and leave the plutonium and/or uranium as oxides. The stabilized material will be sampled to determine the Loss On Ignition (LOI). The stabilized material must meet LOI of less than 0.5% to be acceptable for storage under DOE-STD-3013-94 specifications. Out of specification material will be recycled through the furnaces until the LOI limits are met.

RISENMAY, H.R.

1999-06-01T23:59:59.000Z

392

Process for stabilizing the viscosity characteristics of coal derived materials and the stabilized materials obtained thereby  

SciTech Connect

A process is disclosed for stabilizing the viscosity of coal derived materials such as an SRC product by adding up to 5.0% by weight of a light volatile phenolic viscosity repressor. The viscosity will remain stabilized for a period of time of up to 4 months.

Bronfenbrenner, James C. (Allentown, PA); Foster, Edward P. (Allentown, PA); Tewari, Krishna (Allentown, PA)

1985-01-01T23:59:59.000Z

393

Vertically stabilized elongated cross-section tokamak  

SciTech Connect

This invention provides a vertically stabilized, non-circular (minor) cross-section, toroidal plasma column characterized by an external separatrix. To this end, a specific poloidal coil means is added outside a toroidal plasma column containing an endless plasma current in a tokamak to produce a rectangular cross-section plasma column along the equilibrium axis of the plasma column. By elongating the spacing between the poloidal coil means the plasma cross-section is vertically elongated, while maintaining vertical stability, efficiently to increase the poloidal flux in linear proportion to the plasma cross-section height to achieve a much greater plasma volume than could be achieved with the heretofore known round cross-section plasma columns. Also, vertical stability is enhanced over an elliptical cross-section plasma column, and poloidal magnetic divertors are achieved.

Sheffield, George V. (Hopewell, NJ)

1977-01-01T23:59:59.000Z

394

Radiation stability of biocompatibile magnetic fluid  

E-Print Network (OSTI)

The radiation stability of biocompatibile magnetic fluid used in nanomedicine after electron irradiation was studied. Two types of the water-based magnetic fluids were prepared. The first one was based on the magnetite nanoparticles stabilized by one surfactant natrium oleate. The second one was biocompatibile magnetic fluid stabilized with two surfactants, natrium oleate as a first surfactant and Poly(ethylene glycol) (PEG) as a second surfactant. The magnetization measurements showed that electron irradiation up to 1000Gy caused 50% reduction of saturation magnetization in the case of the first sample with only one surfactant while in the case of the second biocompatibile magnetic fluid, only 25% reduction of saturation magnetization was observed. In the first magnetic fluid the radiation caused the higher sedimentation of the magnetic particles than in the second case, when magnetic particles are covered also with PEG. The obtained results show that PEG behave as a protective element.

Natalia Tomasovicova; Ivan Haysak; Martina Koneracka; Jozef Kovac; Milan Timko; Vlasta Zavisova; Alexander Okunev; Alexander Parlag; Alexey Fradkin; Peter Kopcansky

2010-04-20T23:59:59.000Z

395

Stability of flows in fluidized beds  

Science Conference Proceedings (OSTI)

We study the linearized stability of the state of uniform fluidization, within the context of the theory of mixtures. The mixture is assumed to be made up of a classical linearly viscous fluid mixed with solid particles. In marked departure from most of the previous studies, we model the solid as a granular material and assume a constitutive relation that stems from classical motions in continuum mechanics. The linearized stability analysis of the state of uniform fluidization, in general, leads to an eighth order equation for the characteristic whose root implies instability, when positive. We find that the characteristic equation can be factored and one of the factors is precisely the equation that governs the stability when we use a simplified analysis akin to that of the earlier study of Anderson and Jackson.

Not Available

1993-04-01T23:59:59.000Z

396

Stability windows for proto-quark stars  

E-Print Network (OSTI)

We investigate the existence of possible stable strange matter and related stability windows at finite temperature for different models that are generally applied to describe quark stars, namely, the quark-mass density dependent model, the MIT bag model and the Nambu-Jona-Lasinio model. We emphasize that, although the limits for stable strange matter depend on a comparison with the ground state of 56Fe, which is a zero temperature state, the quantity that has to be used in the search for strange matter in proto-quark stars is the free energy and we analyze stability windows up to temperatures of the order of 40 MeV. The effects of strong magnetic fields on stability windows are computed and the resulting mass-radius relations for different stages of the proto-quark star are analyzed.

V. Dexheimer; J. R. Torres; D. P. Menezes

2013-03-20T23:59:59.000Z

397

Effects of buoyancy on premixed flame stabilization  

SciTech Connect

The stabilization limits of v-flame and conical flames are investigated in normal gravity (+g) and reversed gravity (up-side-down burner, -g) to compare with observations of flame stabilization during microgravity experiments. The results show that buoyancy has most influence on the stabilization of laminar V-flames. Under turbulent conditions, the effects are less significant. For conical flames stabilized with a ring, the stabilization domain of the +g and -g cases are not significantly different. Under reversed gravity, both laminar v-flames and conical flames show flame behaviors that were also found in microgravity. The v-flames reattached to the rim and the conical flame assumed a top-hat shape. One of the special cases of -g conical flame is the buoyancy stabilized laminar flat flame that is detached from the burner. These flame implies a balance between the flow momentum and buoyant forces. The stretch rates of these flames are sufficiently low (< 20 s{sup -1}) such that the displacement speeds S{sub L} are almost equal to the laminar burning speed S{sub L}{sup 0}. An analysis based on evaluating the Richardson number is used to determine the relevant parameters that describe the buoyancy/momentum balance. A perfect balance i.e. Ri = l can be attained when the effect of heat loss from the flame zone is low. For the weaker lean cases, our assumption of adiabaticity tends to overestimate the real flame temperature. This interesting low stretch laminar flame configuration can be useful for fundamental studies of combustion chemistry.

Bedat, B.; Cheng, R.K.

1995-10-01T23:59:59.000Z

398

Renewable source controls for grid stability.  

SciTech Connect

The goal of this study was to evaluate the small signal and transient stability of the Western Electric- ity Coordinating Council (WECC) under high penetrations of renewable energy, and to identify control technologies that would improve the system performance. The WECC is the regional entity responsible for coordinating and promoting bulk electric system reliability in the Western Interconnection. Transient stability is the ability of the power system to maintain synchronism after a large disturbance while small signal stability is the ability of the power system to maintain synchronism after a small disturbance. Tran- sient stability analysis usually focuses on the relative rotor angle between synchronous machines compared to some stability margin. For this study we employed generator speed relative to system speed as a metric for assessing transient stability. In addition, we evaluated the system transient response using the system frequency nadir, which provides an assessment of the adequacy of the primary frequency control reserves. Small signal stability analysis typically identi es the eigenvalues or modes of the system in response to a disturbance. For this study we developed mode shape maps for the di erent scenarios. Prony analysis was applied to generator speed after a 1.4 GW, 0.5 second, brake insertion at various locations. Six di erent WECC base cases were analyzed, including the 2022 light spring case which meets the renewable portfolio standards. Because of the di culty in identifying the cause and e ect relationship in large power system models with di erent scenarios, several simulations were run on a 7-bus, 5-generator system to isolate the e ects of di erent con gurations. Based on the results of the study, for a large power system like the WECC, incorporating frequency droop into wind/solar systems provides a larger bene t to system transient response than replacing the lost inertia with synthetic inertia. From a small signal stability perspective, the increase in renewable penetration results in subtle changes to the system modes. In gen- eral, mode frequencies increase slightly, and mode shapes remain similar. The system frequency nadir for the 2022 light spring case was slightly lower than the other cases, largely because of the reduced system inertia. However, the nadir is still well above the minimum load shedding frequency of 59.5 Hz. Finally, several discrepancies were identi ed between actual and reported wind penetration, and additional work on wind/solar modeling is required to increase the delity of the WECC models.

Byrne, Raymond Harry; Elliott, Ryan Thomas; Neely, Jason C.; Silva Monroy, Cesar Augusto; Schoenwald, David Alan; Grant, Lisa

2012-12-01T23:59:59.000Z

399

Dynamic stability experiment of Maglev systems  

DOE Green Energy (OSTI)

This paper presents dynamic stability experiments on maglev systems and compares with predictions calculated by a nonlinear dynamic computer code. Instabilities of an electrodynamic system (EDS)-type vehicle model were obtained from both experimental observations and computer simulations for a five-degree-of-freedom maglev vehicle moving on a guideway consisting of double L-shaped aluminum segments attached to a rotating wheel. The experimental and theoretical analyses developed in this study identify basic stability characteristics and future research needs of maglev systems.

Cai, Y.; Chen, S.S.; Zhu, S.; Rote, D.M.

1995-12-31T23:59:59.000Z

400

Aluminum-stabilized NB3SN superconductor  

DOE Patents (OSTI)

An aluminum-stabilized Nb.sub.3 Sn superconductor and process for producing same, utilizing ultrapure aluminum. Ductile components are co-drawn with aluminum to produce a conductor suitable for winding magnets. After winding, the conductor is heated to convert it to the brittle Nb.sub.3 Sn superconductor phase, using a temperature high enough to perform the transformation but still below the melting point of the aluminum. This results in reaction of substantially all of the niobium, while providing stabilization and react-in-place features which are beneficial in the fabrication of magnets utilizing superconducting materials.

Scanlan, Ronald M. (Livermore, CA)

1988-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Stability of Anisotropic Cylinder with Zero Expansion  

E-Print Network (OSTI)

We study the dynamical instability of anisotropic collapsing cylinder with the expansion-free condition, which generates vacuum cavity within fluid distribution. The perturbation scheme is applied to distinguish Newtonian, post-Newtonian and post-post Newtonian terms, which are used for constructing dynamical equation at Newtonian and post-Newtonian regimes. We analyze the role of pressure anisotropy and energy density inhomogeneity on the stability of collapsing cylinder. It turns out that stability of the cylinder depends upon these physical properties of the fluid, not on the stiffness of the fluid.

M. Sharif; M. Azam

2013-05-24T23:59:59.000Z

402

Stability of Anisotropic Cylinder with Zero Expansion  

E-Print Network (OSTI)

We study the dynamical instability of anisotropic collapsing cylinder with the expansion-free condition, which generates vacuum cavity within fluid distribution. The perturbation scheme is applied to distinguish Newtonian, post-Newtonian and post-post Newtonian terms, which are used for constructing dynamical equation at Newtonian and post-Newtonian regimes. We analyze the role of pressure anisotropy and energy density inhomogeneity on the stability of collapsing cylinder. It turns out that stability of the cylinder depends upon these physical properties of the fluid, not on the stiffness of the fluid.

Sharif, M

2013-01-01T23:59:59.000Z

403

Effect of point-like disorder on the vortex phase diagram in Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8-{delta}} in oblique field.  

Science Conference Proceedings (OSTI)

The phase diagram of vortex matter in the layered superconductor Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8-{delta}} exposed to a magnetic field oblique to the crystalline c-axis contains two first order transition (FOT) lines. The first, H{sub FOT}{sup m}, separates the vortex solid from the vortex liquid, the second, H{sub FOT}{sup ct}, separates the combined lattice state in the vortex solid from a tilted lattice state. The angular dependence of H{sub FOT}{sup m} in the tilted lattice region follows the anisotropic Ginzburg-Landau model, allowing for the determination of the anisotropy factor {gamma}{sub eff} and the contribution of magnetic coupling to the mutual interaction of 'pancake' vortices in the crossed lattice limit. The later parameter is directly related to the in-plane penetration depth {lambda}{sub ab}. We investigate the evolution of the phase diagram of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8-{delta}} in oblique fields with point-like disorder, introduced by irradiation with 2.3 MeV electrons. Apart from the depression of T{sub c}, point-like disorder induces an increase of {gamma}{sub eff} and a depression of the superfluid density.

Konczykowski, M.; van der Beek, C. J.; Mosser, V.; Koshelev, A. E.; Li, M.; Kes, P. H. (Materials Science Division); (Ecole Polytechnique); (ITRON); (Leiden Univ.)

2010-12-01T23:59:59.000Z

404

NON-BLOCKING STABILIZED FEED BACK AMPLIFIER  

DOE Patents (OSTI)

A plural stuge nonblocking degenerative feed-back amplifier was designed particularly suitable for counting circuits because of the stability and linearity in operation, characterized by the fact that the inltial stage employs a cathode coupled input circuit fed from a cathode follower and the final stage has a tline constant greater than those of the other stages.

Fairstein, E.

1960-03-01T23:59:59.000Z

405

Phase Stability of Multicomponent NAPLs Containing PAHs  

E-Print Network (OSTI)

natural or engineered process that acts to selectively extract compounds will alter NAPL composition examines the relationship between NAPL composition and liquid phase stability for mixtures of polycyclic as a subsurface environmental contaminant at sites of former manufactured gas plants (1). Multicomponent NAPLs

Peters, Catherine A.

406

Boundary stability under nonequilibrium conditions. Final report  

Science Conference Proceedings (OSTI)

Summaries of research accomplished are given for the following areas: Morphological (Diffusional) Stability; A New Algorithm for Numerical Modeling of Non-equilibrium Materials Behavior; A Unified Treatment of Single and Microcrystalline Film Edge Instabilities; and Validation of the Structure Based Grain Boundary Diffusion/Migration Model.

Hackney, S.A.; Lee, J.K.; Plichta, M.R.

1999-08-01T23:59:59.000Z

407

ROCTECtm STABILIZATION TREATMENT OF WERF ASH  

Science Conference Proceedings (OSTI)

The objective of this project is to demonstrate a process to stabilize mixed waste flyash generated by the combustion of mixed waste at the Idaho National Engineering & Environmental Laboratory's (INEEL's) Waste Experimental Reduction Facility (WERF) incinerator such that it will meet Resource Conservation and Recovery Act (RCRA) Land Disposal Restrictions (LDRs) Universal Treatment Standards.

Paul A. Lessing; William J. Quapp; Gary Renlund; Bob Clark; Colin Hundley; James Cornwell; Dave Schlier; John Bulko; Gene Pollack

1998-10-01T23:59:59.000Z

408

Metallic nanoshells on porphyrin-stabilized emulsions  

SciTech Connect

Metal nanostructures formed by photocatalytic interfacial synthesis using a porphyrin-stabilized emulsion template and the method for making the nanostructures. Catalyst-seeded emulsion droplets are employed as templates for hollow-nanoshell growth. The hollow metal nanospheres may be formed with or without inclusions of other materials.

Wang, Haorong; Song, Yujiang; Shelnutt, John A; Medforth, Craig J

2013-10-29T23:59:59.000Z

409

Melt dumping in string stabilized ribbon growth  

DOE Patents (OSTI)

A method and apparatus for stabilizing the edge positions of a ribbon drawn from a melt includes the use of wettable strings drawn in parallel up through the melt surface, the ribbon being grown between the strings. A furnace and various features of the crucible used therein permit continuous automatic growth of flat ribbons without close temperature control or the need for visual inspection.

Sachs, Emanuel M. (42 Old Middlesex Rd., Belmont, MA 02178)

1986-12-09T23:59:59.000Z

410

Stability analysis of heat exchanger dynamics  

Science Conference Proceedings (OSTI)

In the study of vapor compression cycle, momentum balance equation is often ignored in the heat exchanger model. In this paper, we investigate the effect of the momentum balance through a systematic study of the open loop stability of a heat exchanger. ...

Tiejun Zhang; John T. Wen; Juan Catano; Rongliang Zhou

2009-06-01T23:59:59.000Z

411

Stability Issues for w Dark Energy  

E-Print Network (OSTI)

Precision cosmological data hint that a dark energy with equation of state $w = P/\\rho 0$ to $\\Lambda = 0$ in a first-order phase transition. The critical radius is argued to be at least of galactic size and the corresponding nucleation rate is glacial, thus underwriting the dark energy's stability and rendering remote any microscopic effect.

Paul H. Frampton

2003-02-01T23:59:59.000Z

412

KINETICS, STABILITY, AND CONTROL. A Selected Bibliography  

SciTech Connect

References to 529 articles on nuclear reactor control, kinetics, and stability published before autumn 1962 are included. Emphasis is on calculations and theory since the references serve as an aid in analyzing the dynamic behavior of SNAP reactor systems. (D.C.W.)

Johnson, R.L.

1963-03-15T23:59:59.000Z

413

Stability of Free Surface Ekman Layers  

Science Conference Proceedings (OSTI)

The stability of free surface, laminar Ekman layers is examined for both the homogeneous and the two-layer case. The eigenvalues of the homogeneous case depend upon the wavenumbers ? and ? and the Reynolds number Re. Those of the two-layer case ...

George F. Spooner

1983-04-01T23:59:59.000Z

414

Amphiphiles for protein solubilization and stabilization  

DOE Patents (OSTI)

The invention provides amphiphiles for manipulating membrane proteins. The amphiphiles can feature carbohydrate-derived hydrophilic groups and branchpoints in the hydrophilic moiety and/or in a lipophilic moiety. Such amphiphiles are useful as detergents for solubilization and stabilization of membrane proteins, including photosynthetic protein superassemblies obtained from bacterial membranes.

Gellman, Samuel Helmer; Chae, Pil Seok; Laible, Philip D.; Wander, Marc J.

2012-09-11T23:59:59.000Z

415

Broken symmetry as a stabilizing remnant  

Science Conference Proceedings (OSTI)

The Goldberger-Wise mechanism enables one to stabilize the length of the warped extra dimension employed in Randall-Sundrum models. In this work we generalize this mechanism to models with multiple warped throats sharing a common ultraviolet brane. For independent throats this generalization is straightforward. If the throats possess a discrete interchange symmetry like Z{sub n}, the stabilizing dynamics may respect the symmetry, resulting in equal throat lengths, or they may break it. In the latter case the ground state of an initially symmetric configuration is a stabilized asymmetric configuration in which the throat lengths differ. We focus on two- (three-) throat setups with a Z{sub 2} (Z{sub 3}) interchange symmetry and present stabilization dynamics suitable for either breaking or maintaining the symmetry. Though admitting more general application, our results are relevant for existing models in the literature, including the two-throat model with Kaluza-Klein parity, and the three-throat model of flavor with a broken Z{sub 3} symmetry.

Law, Sandy S. C. [Department of Physics, Chung Yuan Christian University, Chung-Li, Taiwan 320 (China); McDonald, Kristian L. [TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T 2A3 (Canada); Max-Planck-Institut fuer Kernphysik, Postfach 10 39 80, 69029 Heidelberg (Germany)

2010-11-15T23:59:59.000Z

416

Annular vortex combustor  

DOE Patents (OSTI)

An apparatus for burning coal water fuel, dry ultrafine coal, pulverized l and other liquid and gaseous fuels including a vertically extending outer wall and an inner, vertically extending cylinder located concentrically within the outer wall, the annnular space between the outer wall and the inner cylinder defining a combustion chamber and the all space within the inner cylinder defining an exhaust chamber. Fuel and atomizing air are injected tangentially near the bottom of the combustion chamber and secondary air is introduced at selected points along the length of the combustion chamber. Combustion occurs along the spiral flow path in the combustion chamber and the combined effects of centrifugal, gravitational and aerodynamic forces cause particles of masses or sizes greater than the threshold to be trapped in a stratified manner until completely burned out. Remaining ash particles are then small enough to be entrained by the flue gas and exit the system via the exhaust chamber in the opposite direction.

Nieh, Sen (Burtonsville, MD); Fu, Tim T. (Camarillo, CA)

1992-01-01T23:59:59.000Z

417

UNDERSTANDING FORCES THAT CONTRIBUTE TO PROTEIN STABILITY: APPLICATION FOR INCREASING PROTEIN STABILITY  

E-Print Network (OSTI)

The aim of this study is to further our understanding of the forces that contribute to protein stability and to investigate how site-directed mutagenesis might be used for increasing protein stability. Eleven proteins ranging from 36 to 370 residues have been studied here. A 36-residue VHP and a 337-residue VlsE were used as model systems for studying the contribution of the hydrophobic effect on protein stability. Mutations were made in both proteins which replaced bulky hydrophobic side chains with smaller ones. All variants were less stable than their wild-type proteins. For VHP, the destabilizing effects of mutations were smaller when compared with similar mutations reported in the literature. For VlsE, a similarity was observed. This different behavior was investigated and reconciled by the difference in hydrophobicity and cavity modeling for both proteins. Therefore, the stabilizing mechanism of the hydrophobic effect appears to be similar for both proteins. Eight proteins were used as model systems for studying the effects of mutating non-proline and non-glycine residues to statistically favored proline and glycine residues in ?-turns. The results suggest that proline mutations generally increase protein stability, provided that the replaced residues are solvent exposed. The glycine mutations, however, only have a stabilizing effect when the wild-type residues have ?, ? angles in the L? region of Ramachandran plot. Nevertheless, this strategy still proves to be a simple and efficient way for increasing protein stability. Finally, using a combination of eight previously identified stabilizing mutations; we successfully designed two RNase Sa variants (7S, 8S) that have both much higher Tms and conformational stabilities than wild-type protein over the entire pH range studied. Further studies of the heat capacity change upon unfolding (?Cps) for both proteins and their variants suggest that residual structure may exist in the denatured state of the 8S variant. An analysis of stability curves for both variants suggests that they achieve their stabilization through different mechanisms, partly attributed to the different role of their denatured states. The 7S variants may have a more rigid denatured state and the 8S variant may have a compact denatured state in comparison with that of wild-type RNase Sa.

Fu, Hailong

2009-05-01T23:59:59.000Z

418

Dissolution Arrest and Stability of Armored Bubbles  

E-Print Network (OSTI)

Dissolving armored bubbles stabilize with nonspherical shapes by jamming the initially Brownian particles adsorbed on their interfaces. In a gas-saturated solution, these shapes are characterized by planar facets or folds for decreasing ratios of the particle to bubble radii. We perform numerical simulations that mimic dissolution, and show that the faceted shape represents a local minimum of energy during volume reduction. This minimum is marked by the vanishing of the Laplace overpressure $\\Delta P$, which together with the existence of a $V$-interval where $d\\Delta P/dV>0$ guarantees stability against dissolution. The reduction of $\\Delta P$ is due to the saddle-shape deformation of most of the interface which accompanies the reduction in the mean curvature of the interface.

Manouk Abkarian; Anand Bala Subramaniam; Shin-Hyun Kim; Ryan Larsen; Seung-Man Yang; Howard A. Stone

2007-03-25T23:59:59.000Z

419

Nonlinear stability of viscous roll waves  

E-Print Network (OSTI)

Extending results of Oh--Zumbrun and Johnson--Zumbrun for parabolic conservation laws, we show that spectral stability implies nonlinear stability for spatially periodic viscous roll wave solutions of the one-dimensional St. Venant equations for shallow water flow down an inclined ramp. The main new issues to be overcome are incomplete parabolicity and the nonconservative form of the equations, which leads to undifferentiated quadratic source terms that cannot be handled using the estimates of the conservative case. The first is handled by treating the equations in the more favorable Lagrangian coordinates, for which one can obtain large-amplitude nonlinear damping estimates similar to those carried out by Mascia--Zumbrun in the related shock wave case, assuming only symmetrizability of the hyperbolic part. The second is handled by the observation that, similarly as in the relaxation and detonation cases, sources occurring in nonconservative components experience greater decay comparable to that experienced b...

Johnson, Matthew; Noble, Pascal

2010-01-01T23:59:59.000Z

420

Stabilization of insertion electrodes for lithium batteries.  

DOE Green Energy (OSTI)

This paper discusses the techniques that are being employed to stabilize LiMn{sub 2}O{sub 4} spinel and composite Li{sub x}MnO{sub 2} positive electrodes. The critical role that spinel domains play in stabilizing these electrodes for operation at both 4 V and 3 V is highlighted. The concept of using an intermetallic electrode MM{prime} where M is an active alloying element and M{prime} is an inactive element (or elements) is proposed as an alternative negative electrode (to carbon) for lithium-ion cells. An analogy to metal oxide insertion electrodes, such as MnO{sub 2}, in which Mn is the electrochemically active ion and O is the inactive ion, is made. Performance data are given for the copper-tin electrode system, which includes the intermetallic phases eta-Cu{sub 6}Sn{sub 5} and Li{sub 2}CuSn.

Thackeray, M. M.

1998-09-03T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Plutonium stabilization and handling (PuSH)  

SciTech Connect

This Functional Design Criteria (FDC) addresses construction of a Stabilization and Packaging System (SPS) to oxidize and package for long term storage remaining plutonium-bearing special nuclear materials currently in inventory at the Plutonium Finishing Plant (PFP), and modification of vault equipment to allow storage of resulting packages of stabilized SNM for up to fifty years. The major sections of the project are: site preparation; SPS Procurement, Installation, and Testing; storage vault modification; and characterization equipment additions. The SPS will be procured as part of a Department of Energy nationwide common procurement. Specific design crit1460eria for the SPS have been extracted from that contract and are contained in an appendix to this document.

Weiss, E.V.

1997-01-23T23:59:59.000Z

422

Factors influencing antioxidant phytochemical stability of teas  

E-Print Network (OSTI)

Tea is second only to water as the most consumed beverage in the world due to its health-promoting benefits and characteristic flavor. Even though many botanical teas such as yaupon holly (Ilex vomitoria) and mamaki (Pipturus albidus) are currently available in the tea market, only limited information is available on their polyphenolic contents containing diverse biological activities. Identification of phenolic compounds was performed using advanced analytical technique of mass spectrometry to provide polyphenolic profile of teas. To present fundamental information of phytochemical stability during tea storage, studies to determine the impacts of tea processing, different packaging materials, and various storage conditions on the phytochemical stability were conducted. Ascorbic acid addition and lowering pH successfully decreased the reduction of phenolic compounds by reducing the rate of oxidative degradation while tea pasteurization accelerated oxidative degradation. Glass bottles were most effective to retain higher concentration of polyphenolics. Tea polyphenolics at lower temperature (3 °C) without light exposure were higher retained in each tea. Tea cream, the complex formed by interaction between polyphenolics, caffeine, protein, and metal ions, is highly undesirable in tea industry since it causes haziness and cloudiness in tea infusion as well as deteriorates sensorial properties. Only limited information is available on tea creaming in non-fermented type teas such as green tea, yaupon holly, and mamaki even though many tea creaming compounds are present in these teas. Therefore, studies were conducted to determine the degree of contribution of the tea creaming compounds to tea creaming and to develop novel chemical methods to minimize tea creaming without detrimental effects. Methods applied in the present study defined that hydrophobic interaction was the driving force make tea cream insoluble in the solution. Results obtained by present studies provided fundamental and practical information to the tea industry in terms of phytochemical stability and suggested storage stability of phytochemicals should be considered during processing and storage, since it could be better retained or improved by applying appropriate methods.

Kim, Youngmok

2008-12-01T23:59:59.000Z

423

308 Building Zone I stabilization and confinement  

SciTech Connect

The 308 Building (Fast Flux Test Facility [FFTF] fuel supply) at the Hanford Site, located in Richland, Washington, is currently in transition to shutdown status. After shutdown, the facility will be maintained/surveilled and turned over to the U.S. Department of Energy (DOE) Office of Facility Transition and Management (EM-60) for utilization, remedial action, or decontamination and decommissioning (D&D). This may require that the facility be maintained in the shutdown mode for up to 30 years. To date, all of the special nuclear material (SNM) has been removed from the facility, potential fuel supply equipment has been preserved, surplus materials and equipment have been excessed, and enclosure cleanup and stabilization has begun. Shutdown planning has been completed, which outlines the major tasks, scope, methodology, and timing for the shutdown activities. A major activity in support of the 308 Building shutdown is the cleanup and stabilization of the enclosures and surface contamination areas. This document identifies the specific designs, processes, and methods to stabilize and confine the radiological material within the enclosures and exhaust ducts to allow shutdown of the active support systems. The designs and steps planned will be effective, are simple, and make maximum use of current technologies and commercial items.

Metcalf, I.L.; Schwartz, K.E.; Rich, J.W.; Benecke, M.W.; Rasmussen, D.E.

1993-10-01T23:59:59.000Z

424

308 Building zone I stabilization and confinement  

SciTech Connect

The 308 Building located on the Hanford Site near Richland, Washington, is currently in transition to shutdown status. After this transition is complete, the facility will be maintained/surveilled and given to the U.S. Department of Energy Office of Facility Transition and Management (EM-60) for utilization, remedial action, or decontamination and decommissioning (D&D). This may require that the facility be maintained in the shutdown status for as long as 30 yrs. To date, all of the special nuclear material (SNM) has been removed, potential fuel supply equipment preserved, surplus materials and equipment excessed, and enclosure cleanup and stabilization completed. A major activity in support of the 308 Building shutdown was the cleanup and stabilization of the enclosures and surface contamination areas. This document discusses the specific designs, processes, and methods used to stabilize and confine the radiological material within the enclosure and exhaust ducts to allow the shutdown of the active support systems. The process and designs employed were effective, yet simple, and maximized the use of current technologies and commercial products.

Metcalf, I.L.; Schwartz, K.E.; Rich, J.W.; Benecke, M.W.; Lanham, G.W.

1994-08-01T23:59:59.000Z

425

Stability and Production of Superheavy Nuclei  

E-Print Network (OSTI)

Beyond uranium heavy elements rapidly become increasingly unstable with respect to spontaneous fission as the proton number Z increases, because of the disruptive effect of the long-range Coulomb force. However, in the region just beyond Z = 100 magic proton and neutron numbers and the associated shell structure enhances nuclear stability sufficiently to allow observation of additional nuclei. Some thirty years ago it was speculated that an island of spherical, relatively stable superheavy nuclei would exist near the next doubly magic proton-neutron combination beyond 208:Pb, that is, at proton number Z = 114 and neutron number N = 184. Theory and experiment now show that there also exists a rock of stability in the vicinity of Z = 110 and N = 162 between the actinide region, which previously was the end of the peninsula of known elements, and the predicted island of spherical superheavy nuclei slightly southwest of the magic numbers Z = 114 and N = 184. We review here the stability properties of the heavy region of nuclei. Just as the decay properties of nuclei in the heavy region depend strongly on shell structure, this structure also dramatically affects the fusion entrance channel. The six most recently discovered new elements were all formed in cold-fusion reactions. We discuss here the effect of the doubly magic structure of the target in cold-fusion reactions on the fusion barrier and on dissipation.

Peter Moller; J. Rayford Nix

1997-09-08T23:59:59.000Z

426

Borehole stability in densely welded tuffs  

SciTech Connect

The stability of boreholes, or more generally of underground openings (i.e. including shafts, ramps, drifts, tunnels, etc.) at locations where seals or plugs are to be placed is an important consideration in seal design for a repository (Juhlin and Sandstedt, 1989). Borehole instability or borehole breakouts induced by stress redistribution could negate the effectiveness of seals or plugs. Breakout fractures along the wall of repository excavations or exploratory holes could provide a preferential flowpath for groundwater or gaseous radionuclides to bypass the plugs. After plug installation, swelling pressures exerted by a plug could induce radial cracks or could open or widen preexisting cracks in the rock at the bottom of the breakouts where the tangential compressive stresses have been released by the breakout process. The purpose of the work reported here is to determine experimentally the stability of a circular hole in a welded tuff sample subjected to various external boundary loads. Triaxial and biaxial borehole stability tests have been performed on densely welded Apache Leap tuff samples and Topopah Spring tuff samples. The nominal diameter of the test hole is 13.3 or 14.4 mm for triaxial testing, and 25.4 mm for biaxial testing. The borehole axis is parallel to one of the principal stress axes. The boreholes are drilled through the samples prior to applying external boundary loads. The boundary loads are progressively increased until breakouts occur or until the maximum load capacity of the loading system has been reached. 74 refs.

Fuenkajorn, K.; Daemen, J.J.K. [Arizona Univ., Tucson, AZ (United States). Dept. of Mining and Geological Engineering

1992-07-01T23:59:59.000Z

427

On the Inertial Stability f the Equatorial Middle Atmosphere  

Science Conference Proceedings (OSTI)

A theory of inertial instability on the equatorial beta-plane is developed with application to the inertial stability of the equatorial middle atmosphere at the solstices. It is shown that the stability of this region depends primarily on two ...

Timothy J. Dunkerton

1981-11-01T23:59:59.000Z

428

Stability of Biodiesel and Biodiesel Blends: Interim Report  

DOE Green Energy (OSTI)

This is an interim report for a study of biodiesel oxidative stability. It describes characterization and accelerated stability test results for 19 B100 samples and six diesel fuels.

McCormick, R. L.; Alleman, T. L.; Waynick, J. A.; Westbrook, S. R.; Porter, S.

2006-04-01T23:59:59.000Z

429

Stabilization of Nickel Metal Catalysts for Aqueous Processing ...  

Search PNNL. PNNL Home; About; Research; Publications; Jobs; News; Contacts; Stabilization of Nickel Metal Catalysts for Aqueous Processing Systems. ...

430

Interim Stabilization Equipment Essential and Support Drawing Plan  

Science Conference Proceedings (OSTI)

This supporting document provides a list of the Essential and Support drawings for the Interim Stabilization project equipment.

KOCH, M.R.

2000-01-14T23:59:59.000Z

431

Interim Stabilization Equipment Essential and Support Drawing Plan  

SciTech Connect

This supporting document provides a list of the Essential and Support drawings for the Interim Stabilization project equipment.

KOCH, M.R.

2000-01-28T23:59:59.000Z

432

Phase Stability, Diffusion, Kinetics and their Applications (PSDK-VII)  

Science Conference Proceedings (OSTI)

Materials Genomics Past & Future: From CALPHAD to Flight · Microstructure Stability of Multi-Materials Systems with Adaptive Microstructures · Modeling of ...

433

Microstructure Stability of Multi-Materials Systems with Adaptive ...  

Science Conference Proceedings (OSTI)

Materials Genomics Past & Future: From CALPHAD to Flight · Microstructure Stability of Multi-Materials Systems with Adaptive Microstructures · Modeling of ...

434

NIST Aids Enhancement of the Security and Stability of the ...  

Science Conference Proceedings (OSTI)

NIST Aids Enhancement of the Security and Stability of the Internet's Domain Name System. For Immediate Release: July 21, 2010. ...

2010-10-05T23:59:59.000Z

435

Fundamentals of a fuzzy-logic-based generalized theory of stability  

Science Conference Proceedings (OSTI)

Stability is one of the fundamental concepts of complex dynamical systems including physical, economical, socioeconomical, and technical systems. In classical terms, the notion of stability inherently associates with any dynamical system and determines ... Keywords: Lipschitz stability, Lyapunov stability, control system, degree of stability, fuzzy differential equations (FDEs), fuzzy dynamical systems, fuzzy functions, fuzzy stability, human centricity, precisiated natural language (PNL), stability

Rafik A. Aliev; Witold Pedrycz

2009-08-01T23:59:59.000Z

436

An intelligent power system stabilizer based hybrid fuzzy learning algorithm  

Science Conference Proceedings (OSTI)

This work aims to develop two adaptive fuzzy control techniques applied on excitation control system for turbo- Alternators, to simulate an Automatic Voltage Regulator and Power Systems Stabilizer (AVR-PSS) in transient stability power system analysis: ... Keywords: ANFIS, AVR - PSS, PID control, fuzzy controller, hybrid learning algorithm, power system stability and robustness, turbo-alternators and excitation

Abdellatif Naceri; Ahmed Massoum; Mohamed Abid

2011-09-01T23:59:59.000Z

437

Graphical description of Pauli measurements on stabilizer states  

E-Print Network (OSTI)

We use a graphical representation of stabilizer states to describe, simply and efficiently, the effect of measurements of Pauli products on stabilizer states. This work complements our earlier work [Phys. Rev. A 77, 042307 (2008)], which described in graphical terms the action of Clifford operations on stabilizer states.

Matthew B. Elliott; Bryan Eastin; Carlton M. Caves

2008-06-16T23:59:59.000Z

438

Criterion of stability of the superconducting state  

E-Print Network (OSTI)

In this paper, we propose to draw attention to the stability criterion of the superconductor current state. We use for this purpose the rough systems mathematical apparatus allowing us to relate the desired criterion with the dielectric permittivity of the matter and to identify the type of all possible phonons trajectories in its superconducting state. The state of superconductivity in the matter can be explained only by the phonons behavior peculiarity. And on the basis of the above-mentioned assumption, the corresponding mathematical model is constructed.

Iogann Tolbatov

2009-10-23T23:59:59.000Z

439

Ceramic membranes with enhanced thermal stability  

DOE Patents (OSTI)

A method of creating a ceramic membrane with enhanced thermal stability is disclosed. The method involves combining quantities of a first metal alkoxide with a second metal, the quantities selected to give a preselected metal ratio in the resultant membrane. A limited amount of water and acid is added to the combination and stirred until a colloidal suspension is formed. The colloid is dried to a gel, and the gel is fired at a temperature greater than approximately 400.degree. C. The porosity and surface area of ceramic membranes formed by this method are not adversely affected by this high temperature firing.

Anderson, Marc A. (Madison, WI); Xu, Qunyin (Plainsboro, NJ); Bischoff, Brian L. (Madison, WI)

1993-01-01T23:59:59.000Z

440

Present status of mirror stability theory  

SciTech Connect

A status report of microinstability as it applies to 2XIIB and MX theory for mirror machines is presented. It is shown that quasilinear computations reproduce many of the parameters observed in the 2XIIB experiment. In regard to large mirror machines, there are presented detailed calculations of the linear theory of the drift cyclotron loss-cone mode, with inhomogeneous geometry and nonlinear diffusive effects. Further, the stability of a mirror machine to the Alfven ion-cyclotron instability is assessed, and the Baldwin- Callen diffusion is estimated for a spatially varying plasma. (auth)

Baldwin, D. E.; Berk, H. L.; Byers, J. A.

1976-02-11T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Oxygen stabilized zirconium-vanadium-iron alloy  

SciTech Connect

An oxygen stabilized intermetallic compound having the formula (Zr.sub.1-x Ti.sub.x).sub.2-u (V.sub.1-y Fe.sub.y)O.sub.z where x=0.0 to 0.9, y=0.01 to 0.9, z=0.25 to 0.5 and u=0 to 1. The compound is capable of reversibly sorbing hydrogen at temperatures from -196.degree. C. to 200.degree. C. at pressures down to 10.sup.-6 torr. The compound is suitable for use as a hydrogen getter in low pressure, high temperature applications such as magnetic confinement fusion devices.

Mendelsohn, Marshall H. (Woodridge, IL); Gruen, Dieter M. (Downers Grove, IL)

1982-01-01T23:59:59.000Z

442

Flow Stability of Supercritical Water Cooled Systems  

SciTech Connect

Research activities are ongoing worldwide to develop nuclear power plants with supercritical water cooled reactor (SCWR) with the purpose to achieve a high thermal efficiency and to improve their economical competitiveness. However, the strong variation of the thermal-physical properties of water in the vicinity of the pseudo-critical line results in challenging tasks in thermal-hydraulic design of a SCWR. One of the challenging tasks is to understand and to predict the dynamic behavior and flow stability of supercritical water cooled systems. Although extensive thermal-hydraulic research activities have been carried out worldwide, studies on flow stability of SC water cooled systems are scarce. The present study deals with the flow behavior of SC water cooled systems. For this purpose the computer code SASC was developed, which is applied to a simplified cooling system. The effect of various parameters on the flow behavior is investigated. The first results achieved up to now reveals a complicated dynamic performance of a system cooled by supercritical water. (authors)

Cheng, X.; Kuang, B.; Yang, Y.H. [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, 1954 Hua Shan Road, Shanghai 200030 (China)

2006-07-01T23:59:59.000Z

443

On the stability of the Kerr metric  

E-Print Network (OSTI)

The reduced (in the angular coordinate $\\phi$) wave equation and Klein-Gordon equation are considered on a Kerr background and in the framework of $C^{0}$-semigroup theory. Each equation is shown to have a well-posed initial value problem,i.e., to have a unique solution depending continuously on the data. Further, it is shown that the spectrum of the semigroup's generator coincides with the spectrum of an operator polynomial whose coefficients can be read off from the equation. In this way the problem of deciding stability is reduced to a spectral problem and a mathematical basis is provided for mode considerations. For the wave equation it is shown that the resolvent of the semigroup's generator and the corresponding Green's functions can be computed using spheroidal functions. It is to be expected that, analogous to the case of a Schwarzschild background, the quasinormal frequencies of the Kerr black hole appear as {\\it resonances}, i.e., poles of the analytic continuation of this resolvent. Finally, stability of the background with respect to reduced massive perturbations is proven for large enough masses.

Horst R. Beyer

2000-08-16T23:59:59.000Z

444

Application of the Direct Liapunov Method to the Problem of Symmetric Stability in the Atmosphere  

Science Conference Proceedings (OSTI)

The problem of symmetric stability is examined within the context of the direct Liapunov method. The sufficient conditions for stability derived by Fjørtoft are shown to imply finite-amplitude, normed stability. This finite-amplitude stability ...

H-R. Cho; T. G. Shepherd; V. A. Vladimirov

1993-03-01T23:59:59.000Z

445

Stabilizing trust and reputation for self-stabilizing efficient hosts in spite of Byzantine guests  

Science Conference Proceedings (OSTI)

This work presents a general and complete method to protect a system against possible malicious programs. We provide concepts for building a system that can automatically recover from an arbitrary state including even one in which a Byzantine execution ... Keywords: byzantine programs, host systems, security, self-stabilization, trust and reputation

Shlomi Dolev; Reuven Yagel

2007-11-01T23:59:59.000Z

446

Uv-Light Stabilization Additive Package For Solar Cell Module And Laminated Glass Applications  

SciTech Connect

An ultraviolet light stabilization additive package is used in an encapsulant material that may be used in solar cell modules, laminated glass and a variety of other applications. The ultraviolet light stabilization additive package comprises a first hindered amine light stabilizer and a second hindered amine light stabilizer. The first hindered amine light stabilizer provides thermal oxidative stabilization, and the second hindered amine light stabilizer providing photo-oxidative stabilization.

Hanoka, Jack I. (Brookline, MA); Klemchuk, Peter P. (Watertown, CT)

2002-03-05T23:59:59.000Z

447

Superconducting magnetic energy storage for electric power system dynamic stabilization  

DOE Green Energy (OSTI)

A Superconducting Magnetic Energy Storage (SMES) system is being developed at the Los Alamos Scientific Laboratory (LASL) for a dynamic stabilizer to be installed in the Bonneville Power Administration (BPA) power system at Tacoma, Washington, by 1982. This unit will be an alternate stabilization method to the dc modulator now used to stabilize the 900 mile, ac intertie between BPA and Southern California. The generation control systems' response to the constantly occuring, small-load and voltage changes can result in negatively damped, low-frequency power oscillations. The dc modulator provides stabilization by fast load control of the High-Voltage dc (HVDC). The SMES unit consists of a 30-MJ solenoid, a 10 MW convertor, a liquid helium dewar and auxiliary systems which operate independent of the HVDC system. The SMES dynamic stabilizer design is presented with status information about the superconducting coil, the converter and other components of the SMES dynamic stabilizer summarized.

Turner, R.

1979-01-01T23:59:59.000Z

448

Superconducting Magnetic Energy Storage for electric power system dynamic stabilization  

DOE Green Energy (OSTI)

A Superconducting Magnetic Energy Storage (SMES) system is being developed at the Los Alamos Scientific Laboratory (LASL) for a dynamic stabilizer to be installed in the Bonneville Power Administration (BPA) power system at Tacoma, Washington, by 1982. This unit will be an alternate stabilization method to the dc modulator now used to stabilize the 900 mile, ac intertie between BPA and Southern California. The generation control systems' response to the constantly occurring, small-load and voltage changes can result in negatively damped, low-frequency power oscillations. The dc modulator provides stabilization by fast load control of the High-Voltage dc (HVDC). The SMES unit consists of a 30-MJ solenoid, a 10-MW convertor, a liquid helium dewar, and auxiliary systems which operate independent of the HVDC system. The SMES dynamic stabilizer design is presented and status information is given about the superconducting coil, the converter, and other components of the SMES dynamic stabilizer.

Turner, R.D.

1979-01-01T23:59:59.000Z

449

Lee-Vortex Formation in Free-Slip Stratified Flow over Ridges. Part I: Comparison of Weakly Nonlinear Inviscid Theory and Fully Nonlinear Viscous Simulations  

Science Conference Proceedings (OSTI)

The formation of lee wakes and vortices is explored in the context of stratified flow with uniform basic-state wind and stability past elongated free-slip ridges.

C. C. Epifanio; D. R. Durran

2002-04-01T23:59:59.000Z

450

On the stability of subsonic thermal fronts  

Science Conference Proceedings (OSTI)

The stability of subsonic thermal fronts against corrugation is analyzed and an exact dispersion relation is obtained taking into account the compressibility of the gas. For heat fronts, this dispersion equation has an unstable root ({omega}{sub ex}) corresponding to the Landau-Darrieus unstable mode ({omega}{sub 0}) modified by the compressional effects. In particular, the exact solution shows a conspicuous maximum very close to the value of the intake Mach number M{sub 1} at which a Chapman-Jouguet deflagration wave behind the heat front is formed. Cooling fronts are stable for corrugation-like disturbances. A maximum damping as well as a maximum in the frequency occur at a value of M{sub 1} depending on the value of the normalized cooling q.

Ibanez S, Miguel H.; Shchekinov, Yuri; Bessega L, Maria C. [Centro de Fisica Fundamental, Facultad de Ciencias, Universidad de los Andes, Apartado 26, Ipostel, La Hechicera, Merida (Venezuela); Department of Physics, University of Rostov, Rostov on Don, 34409 (Russian Federation); Centro de Fisica Teorica y Computacional, Escuela de Fisica, Facultad de Ciencias, Universidad Central de Venezuela, Caracas (Venezuela)

2005-08-15T23:59:59.000Z

451

Radion Physics, Stability and Cosmological issues  

Science Conference Proceedings (OSTI)

Moduli fields are a known ingredient of models that involve extra compact dimensions, as the Kaluza-Klein theories, String theory, and models with compact extra dimensions. They are scalar fields that emerge when the configuration of the compact space is perturbed. The radion is a particular example of this type of fields, which is associated to the variations of the total volume of compact space. Radions usually couple to all other fields, affecting the definition of coupling constants and gravity strength. They also modify gravitational potentials in a way that may be tested in table top experiments. Usually, these fields are run away modes which manifest the difficulties to stabilize the shape of the compact manifold of extra space. This is feature that can be a threat for cosmology on the early Universe. Here we provide a brief discussion of these general aspects of the radion physics.

Perez-Lorenzana, Abdel [Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del I.P.N. Apdo. Post. 14-740, 07000, Mexico, D.F. (Mexico); Santos, Eli [Centro de Estudios en Fisica y Matematicas Basicas y Aplicadas, UNACH, 4a Oriente Norte 1428, C.P. 29000 Tuxtla Gutierrez, Chiapas (Mexico); Instituto de Fisica y Matematicas, Universidad Michoacana de San Nicolas de Hidalgo Edificio C-3, Ciudad Universitaria, CP. 58040 Morelia, Michoacan (Mexico)

2010-07-12T23:59:59.000Z

452

Stabilizing windings for tilting and shifting modes  

DOE Patents (OSTI)

This invention provides simple, inexpensive, independent and passive, conducting loops for stabilizing a plasma ring having externally produced equilibrium fields on opposite sides of the plasma ring and internal plasma currents that interact to tilt and/or shift the plasma ring relative to the externally produced equilibrium field so as to produce unstable tilting and/or shifting modes in the plasma ring. More particularly this invention provides first and second passive conducting loops for containing first and second induced currents in first and second directions corresponding to the amplitude and directions of the unstable tilting and/or shifting modes in the plasma ring. To this end, the induced currents provide additional magnetic fields for producing restoring forces and/or restoring torques for counteracting the tilting and/or shifting modes when the conducting loops are held fixed in stationary positions relative to the externally produced equilibrium fields on opposite sides of the plasma ring.

Jardin, S.C.; Christensen, U.R.

1982-02-26T23:59:59.000Z

453

Partially stabilized zirconia piston bowl reliability  

SciTech Connect

The Weibull based ''Simplified Structural Ceramic Design Technique'' was used to calculate the reliability of a partially stabilized zirconia (PSZ) piston bowl design. The details of the method and a set of sample calculations are presented. Test results of the piston bowl showed cracks in regions which had a high calculated probability of failure. In addition cracks developed in a region of high compressive/shear stress. Since Weibull reliability analysis only uses tensile stresses this area did not have a high calculated probability of failure. Several hypotheses are presented for the mode of failure in this region. The simplified technique was used to predict what the necessary material properties would have to be for successful PSZ insert of the design shown.

Hartsock, D.L.

1987-10-01T23:59:59.000Z

454

Stability of chromite interconnections in dual environments  

DOE Green Energy (OSTI)

One of the most critical technical concerns in high-temperature SOFCs is the physical, chemical, and electrical stability of the interconnect (typically a doped lanthanum chromite) in the dual (oxidizing and reducing atmosphere) SOFC environment. The reducing or fuel side may experience oxygen partial pressures (P(O{sub 2})) from 10{sup {minus}18} to 10{sup {minus}6} atmospheres, while the oxidizing side may have P(O{sub 2}) from 10{sup {minus}6} to greater than 1 atm. These conditions limit the possible candidate materials to lanthanum or yttrium chromites. In the past decade, much work has centered on development of air-sinterable chromites and understanding their physical properties; little work, however, has focused on the stability of these chromites in dual environments. Chromite powders were synthesized using the glycine-nitrate process. The powders were calcined at 1,000 C for 1 hour and then uniaxially pressed into bars (46mm x 16mm x 3mm) at 55 MPa and isostatically pressed at 138 MPa. Samples were sintered in air. The dependence of the physical properties of sintered lanthanum chromites upon ambient P(O{sub 2}) and temperature (using dilatometry, thermogravimetric analysis, and oxygen permeation measurements) were studied. La{sub 1{minus}x}A{sub x}CrO{sub 3} and Y{sub 1{minus}x}Ca{sub x}CrO{sub 3}, where A is Ca or Sr and x was varied from 0.1 to 0.4 were evaluated in this study. The P(O{sub 2}) was varied using a buffered CO{sub 2}/Ar-4%H{sub 2} gas system, enabling expansion measurements to be made over a partial pressure range from 10{sup {minus}5} to 10{sup {minus}18} atmosphere at 800, 900, and 1,000 C.

Armstrong, T.R.; Stevenson, J.W.; Raney, P.; Pederson, L.R.

1994-11-01T23:59:59.000Z

455

Minimum Additive Waste Stabilization (MAWS). Technology summary  

Science Conference Proceedings (OSTI)

In the Minimum Additive Waste Stabilization(MAWS) concept, actual waste streams are utilized as additive resources for vitrification, which may contain the basic components (glass formers and fluxes) for making a suitable glass or glassy slag. If too much glass former is present, then the melt viscosity or temperature will be too high for processing; while if there is too much flux, then the durability may suffer. Therefore, there are optimum combinations of these two important classes of constituents depending on the criteria required. The challenge is to combine these resources in such a way that minimizes the use of non-waste additives yet yields a processable and durable final waste form for disposal. The benefit to this approach is that the volume of the final waste form is minimized (waste loading maximized) since little or no additives are used and vitrification itself results in volume reduction through evaporation of water, combustion of organics, and compaction of the solids into a non-porous glass. This implies a significant reduction in disposal costs due to volume reduction alone, and minimizes future risks/costs due to the long term durability and leach resistance of glass. This is accomplished by using integrated systems that are both cost-effective and produce an environmentally sound waste form for disposal. individual component technologies may include: vitrification; thermal destruction; soil washing; gas scrubbing/filtration; and, ion-exchange wastewater treatment. The particular combination of technologies will depend on the waste streams to be treated. At the heart of MAWS is vitrification technology, which incorporates all primary and secondary waste streams into a final, long-term, stabilized glass wasteform. The integrated technology approach, and view of waste streams as resources, is innovative yet practical to cost effectively treat a broad range of DOE mixed and low-level wastes.

Not Available

1994-02-01T23:59:59.000Z

456

Landfill stabilization focus area: Technology summary  

SciTech Connect

Landfills within the DOE Complex as of 1990 are estimated to contain 3 million cubic meters of buried waste. The DOE facilities where the waste is predominantly located are at Hanford, the Savannah River Site (SRS), the Idaho National Engineering Laboratory (INEL), the Los Alamos National Laboratory (LANL), the Oak Ridge Reservation (ORR), the Nevada Test Site (NTS), and the Rocky Flats Plant (RFP). Landfills include buried waste, whether on pads or in trenches, sumps, ponds, pits, cribs, heaps and piles, auger holes, caissons, and sanitary landfills. Approximately half of all DOE buried waste was disposed of before 1970. Disposal regulations at that time permitted the commingling of various types of waste (i.e., transuranic, low-level radioactive, hazardous). As a result, much of the buried waste throughout the DOE Complex is presently believed to be contaminated with both hazardous and radioactive materials. DOE buried waste typically includes transuranic-contaminated radioactive waste (TRU), low-level radioactive waste (LLW), hazardous waste per 40 CFR 26 1, greater-than-class-C waste per CFR 61 55 (GTCC), mixed TRU waste, and mixed LLW. The mission of the Landfill Stabilization Focus Area is to develop, demonstrate, and deliver safer,more cost-effective and efficient technologies which satisfy DOE site needs for the remediation and management of landfills. The LSFA is structured into five technology areas to meet the landfill remediation and management needs across the DOE complex. These technology areas are: assessment, retrieval, treatment, containment, and stabilization. Technical tasks in each of these areas are reviewed.

NONE

1995-06-01T23:59:59.000Z

457

The space of stability conditions for $A_3$-quiver.  

E-Print Network (OSTI)

The author studied in \\cite{shi} the covering map property of the local homeomorphism associating to the space of stability conditions over the $n$-Kronecker quiver. In this paper, we discuss the covering map property for stability conditions over the Dynkin quiver of type $A_3$. The local homeomorphism from a connected component of stability conditions over $A_3$ to 3-dimensional complex vector space becomes a covering map when we restrict it to the complement of six codimension one subspaces.

Takahisa Shiina

458

Miniature Biofuel Cells with Improved Stability under Continuous Operation  

SciTech Connect

We have developed miniature biofuel cells (BFCs) with dimensions as small as 12x12x9 mm by adopting the design of stackable proton exchange membrane (PEM) fuel cells. The enzymatic anodes were constructed by using stabilized glucose oxidase (GOx) in the form of crosslinked enzyme clusters (CECs) on the surface of carbon nanotubes (CNTs). The combination of stabilized GOx and unbuffered fuel solution resulted in stabilized performance of miniature BFCs under continuous operation for more than 16 hours. This unprecedentedly high operational stability of miniature BFCs opens up new possibilities for many BFC applications.

Fishback, Michael; Youn, Jongkyu; Zhao, Xueyan; Wang, Ping; Park, Hyun-Gyu; Chang, Ho Nam; Kim, Jungbae; Ha, Su Y.

2006-10-01T23:59:59.000Z

459

PH/sub 3/ treatment for polymer stabilization  

DOE Patents (OSTI)

Polymers are stabilized against oxidative degradation by treatment with phosphine gas. The treatment can be used in situ on polymeric components already in use.

Not Available

1982-07-20T23:59:59.000Z

460

Thermal Stability of Al 5356 Processed by Cryomilling and Spark ...  

Science Conference Proceedings (OSTI)

... Thermal Stability of Al 5356 Processed by Cryomilling and Spark Plasma Sintering ... Ordered Complexions: The Structure and Energy of Ni-Al2O3 Interfaces.

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Leaching of Trace Elements From Highway Materials Stabilized ...  

Leaching of Trace Elements From Highway Materials Stabilized with Coal Fly Ash Craig H. Benson, PhD, PE Professor, Geo Engineering Program Dept. of ...

462

Phase Stability, Diffusion, Kinetics and their Applications (PSDK-VIII)  

Science Conference Proceedings (OSTI)

Mar 31, 2013 ... Michael Gao, National Energy Technology Lab. Scope, Phase stability and diffusion are central themes of materials science and engineering, ...

463

Existence and stability results based on asymptotic analysis for ...  

E-Print Network (OSTI)

Jan 1, 2012 ... Existence and stability results based on asymptotic analysis for semidefinite linear complementarity problems ... Hector Ram rez C.(hramirez.

464

Thermal Convection: Patterns, Evolution and Stability by M. Lappa  

E-Print Network (OSTI)

Review of the book "Thermal Convection: Patterns, Evolution and Stability" by M. Lappa. Invited by the journal Geophysical and Astrophysical Fluid Dynamics.

Simitev, R D

2010-01-01T23:59:59.000Z

465

NETL: News Release - Oil Well Stability Studies Underway in the...  

NLE Websites -- All DOE Office Websites (Extended Search)

October 20, 2003 Oil Well Stability Studies Underway in the Gulf of Mexico Initial Results of Salt Mobility Studies Help Industry Cut Costs, Improve Odds of Deepwater Drilling...

466

Stress Corrosion Cracking of Stabilized Austenitic Stainless Steels ...  

Science Conference Proceedings (OSTI)

Aug 1, 1999 ... Stress Corrosion Cracking of Stabilized Austenitic Stainless Steels in Various Types of Nuclear Power Plants by M.O. Speidel and R.

467

Contribution of Tissue Level Organization to Genomic Stability...  

NLE Websites -- All DOE Office Websites (Extended Search)

of Tissue Level Organization to Genomic Stability Following Low Dose Gamma Irradiation Cheryl Burrell Loma Linda University Abstract Our study proposes that the level of...

468

Local stabilizer codes in three dimensions without string logical operators  

Science Conference Proceedings (OSTI)

We suggest concrete models for self-correcting quantum memory by reporting examples of local stabilizer codes in 3D that have no string logical operators. Previously known local stabilizer codes in 3D all have stringlike logical operators, which make the codes non-self-correcting. We introduce a notion of ''logical string segments'' to avoid difficulties in defining one-dimensional objects in discrete lattices. We prove that every stringlike logical operator of our code can be deformed to a disjoint union of short segments, each of which is in the stabilizer group. The code has surfacelike logical operators whose partial implementation has unsatisfied stabilizers along its boundary.

Haah, Jeongwan [Institute for Quantum Information, California Institute of Technology, Pasadena, California 91125 (United States)

2011-04-15T23:59:59.000Z

469

Tuning of Power System Stabilizers via Genetic Algorithm for ...  

Science Conference Proceedings (OSTI)

Abstract. The paper considers simultaneous placement and tuning of power .... A: proportional to electrical power and a derivative-type power stabilizer with the.

470

Stabilizing coal-water mixtures with portland cement  

DOE Patents (OSTI)

Coal-water mixes stabilized by the addition of portland cement which may additionally contain retarding carbohydrates, or borax are described.

Steinberg, Meyer (Melville, NY); Krishna, Coimbatore R. (Mount Sinai, NY)

1986-01-01T23:59:59.000Z

471

Transient Stability Analysis of Power Systems with Energy Storage.  

E-Print Network (OSTI)

??Power systems can effectively damp power system oscillations through appropriate management of real or reactive power. This thesis addresses some problems in power system stability… (more)

WENG, CHIYUAN

2013-01-01T23:59:59.000Z

472

Apparatus and Method for Oxidation and Stabilization of ...  

... more cost-effective method of oxidizing and stabilizing thermoplastic materials than is currently used in conventional carbon fiber ... The production of carbon ...

473

Method to Increase Stabilization Rate of Lignin for Carbon ...  

Method to Increase Stabilization Rate of Lignin for Carbon Fiber Production Note: The technology described above is an early stage opportunity.

474

Stability of Alfven waves in an inhomogeneous plasma  

SciTech Connect

The stability of Alfven waves in an inhomogeneous plasma into which a beam of fast ions is injected is discussed. (AIP) (AIP)

Timofeev, A.V.

1976-05-01T23:59:59.000Z

475

Optimization Online - On the Dynamic Stability of Electricity Markets  

E-Print Network (OSTI)

Jan 31, 2011 ... On the Dynamic Stability of Electricity Markets. Victor M. Zavala (vzavala ***at*** mcs.anl.gov) Mihai Anitescu (anitescu ***at*** mcs.anl.gov).

476

Stabilizing coal-water mixtures with Portland cement  

DOE Patents (OSTI)

Coal-water mixes stabilized by the addition of Portland cement which may additionally contain retarding carbohydrates, or borax are described. 1 tab.

Steinberg, M.; Krishna, C.R.

1984-10-17T23:59:59.000Z

477

MHK Technologies/Mobil Stabilized Energy Conversion Platform | Open Energy  

Open Energy Info (EERE)

MHK Technologies/Mobil Stabilized Energy Conversion Platform MHK Technologies/Mobil Stabilized Energy Conversion Platform < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Mobil Stabilized Energy Conversion Platform.jpg Technology Profile Primary Organization Aqua Magnetics Inc Technology Resource Click here Wave Technology Type Click here Reciprocating Device Technology Readiness Level Click here TRL 1 3 Discovery Concept Def Early Stage Dev Design Engineering Technology Description The Stabilized Energy Conversion Platform SECOP consists of submersible hulls supporting a raised work platform containing a number of AMI s reciprocating electric generators Technology Dimensions Device Testing Date Submitted 34:44.5 << Return to the MHK database homepage Retrieved from

478

Effective field theory for two-species bosons in an optical lattice: Multiple order, the Nambu-Goldstone bosons, the Higgs mode and vortex lattice  

E-Print Network (OSTI)

In the previous papers, we studied the bosonic t-J mode and derived an effective field theory, which is a kind of quantum XY model. The bosonic t-J model is expected to be realized by experiments of two-component cold atoms in an optical lattice. In this paper, we consider a similar XY model that describes phase diagram of the t-J model with a mass difference. Phase diagram and critical behavior of the quantum XY model are clarified by means of the Monte-Carlo simulations. Effective field theory that describes the phase structure and low-energy excitations of the quantum XY model is derived. Nambu-Goldstone bosons and the Higgs mode are studied by using the effective field theory and interesting findings are obtained for the system with multiple order, i.e., Bose-Einstein condensations and pseudo-spin symmetry. We also investigate physical properties of the quantum XY model in an effective magnetic field that is realized by rotating the optical lattice, etc. We show that low-energy states of the system strongly depend on the strength of the "magnetic field". For some specific strength of the magnetic field, vortex lattice forms and the correlation function of the bosons exhibits solid like behavior, which is a kind of Bose-Einstein condensation.

Y. Kuno; K. Suzuki; I. Ichinose

2013-06-10T23:59:59.000Z

479

Stability and control of the UAV formations flight  

Science Conference Proceedings (OSTI)

The purpose of this paper is to analyze the flight stability of an Unmanned Aerial Vehicles (UAV) formation by using 3 degrees of freedom (3 DOF) models. The problem of flight formation will be approached in a simple manner, by using 3 DOF nonlinear ... Keywords: automation, control, flight, formation, simulation, stability

Teodor-Viorel Chelaru; Valentin Pan?

2010-01-01T23:59:59.000Z

480

Spin-stabilized magnetic levitation without vertical axis of rotation  

DOE Patents (OSTI)

The symmetry properties of a magnetic levitation arrangement are exploited to produce spin-stabilized magnetic levitation without aligning the rotational axis of the rotor with the direction of the force of gravity. The rotation of the rotor stabilizes perturbations directed parallel to the rotational axis.

Romero, Louis (Albuquerque, NM); Christenson, Todd (Albuquerque, NM); Aaronson, Gene (Albuquerque, NM)

2009-06-09T23:59:59.000Z

Note: This page contains sample records for the topic "vortex stabilizer pneumatic" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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481

Stability of Partial Functional Integro-Differential Equations  

Science Conference Proceedings (OSTI)

Using the Fourier method of separation of variables and a procedure proposed in this paper, namely, reducing integrodifferential equations to systems of ordinary differential equations, the exponential stability of partial functional integro-differential ... Keywords: Cauchy matrix, Functional differential equations, exponential stability, phase transition model

R. P. Agarwal; A. Domoshnitsky; Ya. Goltser

2006-01-01T23:59:59.000Z

482

Propulsion and stabilization system for magnetically levitated vehicles  

DOE Patents (OSTI)

A propulsion and stabilization system for an inductive repulsion type magnetically levitated vehicle which is propelled and stabilized by a system which includes propulsion windings mounted above and parallel to vehicle-borne suspension magnets. A linear synchronous motor is part of the vehicle guideway and is mounted above and parallel to superconducting magnets attached to the magnetically levitated vehicle.

Coffey, Howard T. (Darien, IL)

1993-06-29T23:59:59.000Z

483

A Lyapunov approach to the stability of fractional differential equations  

Science Conference Proceedings (OSTI)

Lyapunov stability of fractional differential equations is addressed in this paper. The key concept is the frequency distributed fractional integrator model, which is the basis for a global state space model of FDEs. Two approaches are presented: the ... Keywords: Fractional differential equations, Fractional integrator, Lyapunov stability, Nonlinear FDEs, State space models

J. C. Trigeassou; N. Maamri; J. Sabatier; A. Oustaloup

2011-03-01T23:59:59.000Z

484

Shock propagation and stability in causal dissipative hydrodynamics  

E-Print Network (OSTI)

We studied the shock propagation and its stability with the causal dissipative hydrodynamics in 1+1 dimensional systems. We show that the presence of the usual viscosity is not enough to stabilize the solution. This problem is solved by introducing an additional viscosity which is related to the coarse-graining scale of the theory.

G. S. Denicol; T. Kodama; T. Koide; Ph. Mota

2008-05-12T23:59:59.000Z

485

Effects of unbalanced faults on transient stability of cogeneration system  

Science Conference Proceedings (OSTI)

This paper evaluates the effects of unbalanced faults on the transient stability of a real cogeneration plant. First, a brief is given for the structure of the cogeneration system. Use of the electromagnetic transient program (EMTP) constructs the cogeneration ... Keywords: CCT curve, EMTP, cogeneration plant, transient stability, unbalanced faults

Wei-Neng Chang; Chia-Han Hsu

2011-10-01T23:59:59.000Z

486

Some Thoughts on Stability in Nonlinear Periodic Focusing Systems  

DOE R&D Accomplishments (OSTI)

A brief discussion is given of the long-term stability of particle motions through periodic focusing structures containing lumped nonlinear elements. A method is presented whereby one can specify the nonlinear elements in such a way as to generate a variety of structures in which the motion has long-term stability.

McMillan, E. M.

1967-09-05T23:59:59.000Z

487

Finite-Amplitude Stability of a Zonal Shear Flow  

Science Conference Proceedings (OSTI)

We consider the stability of a zonal shear flow u¯ = tanhy in the framework of the ?-plane approximation. The objective of this study is to determine the effects of nonlinearity on the stability of the flow by perturbing about the known linear ...

A. G. Burns; S. A. Maslowe

1983-01-01T23:59:59.000Z

488

Dynamic instant gait stability measure for quadruped walking robot  

Science Conference Proceedings (OSTI)

A mathematic model is developed for a quadruped walking robot to investigate the dynamic stability considering all the inertial effects in the system including those of legs. The dynamic model is derived based on Lagrange's equation using matrix-vector ... Keywords: Angular momentum about a line, Dynamic model, Gait stability measure, Quadruped walking robot

Tae-Wan Koo; Yong-San Yoon

1999-01-01T23:59:59.000Z

489

Automatic stability checking for large linear analog integrated circuits  

Science Conference Proceedings (OSTI)

Stability analysis is one of the key challenges in the design of large linear analog circuits with complex multi-loop structures. In this paper, we present an efficient loop finder algorithm to identify potentially unstable loops in such circuits. At ... Keywords: analog circuit design, eigenvalue problem, model order reduction, small-signal analysis, stability analysis

Parijat Mukherjee; G. Peter Fang; Rod Burt; Peng Li

2011-06-01T23:59:59.000Z

490

Propulsion and stabilization system for magnetically levitated vehicles  

DOE Patents (OSTI)

A propulsion and stabilization system for an inductive repulsion type magnetically levitated vehicle which is propelled and stabilized by a system which includes propulsion windings mounted above and parallel to vehicle-borne suspension magnets. A linear synchronous motor is part of the vehicle guideway and is mounted above and parallel to superconducting magnets attached to the magnetically levitated vehicle.

Coffey, H.T.

1992-12-31T23:59:59.000Z

491

Thermal stabilization of uranium mill tailings  

SciTech Connect

The sintering of tailings at high temperatures (1200/sup 0/C) has shown promise as a conditioning approach that greatly reduces the /sup 222/Rn emanation of uranium mill tailings. The structure of thermally stabilized tailings has been appreciably altered producing a material that will have minimal management requirements and will be applicable to on-site processing and disposal. The mineralogy of untreated tailings is presented to define the structure of the orig