Sample records for flow conditions cxs

  1. Fluctuating initial conditions and fluctuations in elliptic and triangular flow

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2012-02-24T23:59:59.000Z

    In heavy ion collisions, event-by-event fluctuations in participating nucleon positions can lead to triangular flow. With fluctuating initial conditions, flow coefficients will also fluctuate. In a hydrodynamic model, we study the fluctuations in elliptic and triangular flow, due to fluctuating initial conditions. Both elliptic and triangular flow fluctuates strongly, triangular flow more strongly than the elliptic flow. Strong fluctuations greatly reduce the sensitivity of elliptic and triangular flow to viscosity.

  2. Fluctuating initial conditions and fluctuations in elliptic and triangular flow

    E-Print Network [OSTI]

    Chaudhuri, A K

    2011-01-01T23:59:59.000Z

    In heavy ion collisions, event-by-event fluctuations in participating nucleon positions can lead to triangular flow. In a hydrodynamic model with fluctuating initial conditions, we study the fluctuations in elliptic and triangular flow. Both elliptic and triangular flow fluctuates strongly. Strong fluctuations greatly reduces the sensitivity of elliptic and triangular flow on viscosity.

  3. NEUTROPHILS INFLUENCE MELANOMA ADHESION AND MIGRATION UNDER FLOW CONDITIONS

    E-Print Network [OSTI]

    Dong, Cheng

    NEUTROPHILS INFLUENCE MELANOMA ADHESION AND MIGRATION UNDER FLOW CONDITIONS Margaret J. SLATTERY State University, University Park, PA, USA We have studied human melanoma cell (C8161) adhesion to be very low on these melanoma cells. As a result, C8161 trans- endothelial migration under a flow

  4. The effects between two slotted plate flow meter under single, two, three components flow condition

    E-Print Network [OSTI]

    Park, Sang Hyan

    2005-02-17T23:59:59.000Z

    suggested a universal calibration for the slotted flow meter under various situations using only the Euler number (Eu) and the ratio of ? = AAslot pipe The calibration curve of the slotted meter?s flow coefficient KY versus Euler number was obtained..., or Three Component Flow Conditions. (December 2004) Sang Hyun Park, B.S., Yonsei University, Republic of Korea Chair of Advisory Committee: Dr. Gerald L. Morrison In previous work on the slotted flow meter, repeatibility and reproducibility were studied...

  5. Analysis of pressure drops under reversing flow conditions

    SciTech Connect (OSTI)

    Krazinski, J.L.; Holtz, R.E.; Uherka, K.L.; Lottes, P.A.

    1986-01-01T23:59:59.000Z

    This paper examines pressure-drop data from the Reversing Flow Test Facility (RFTF) at Argonne National Laboratory (ANL). The data comprise part of an initial series of measurements conducted with pressurized helium gas under reversing flow conditions. The characteristics of fluid pressure drops in compressible, reversing flows are discussed in the paper and compared with pressure-drop measurements for steady, incompressible flows. The methodology used to calculate instantaneous mass flows in the test section of the RFTF is summarized. The measured pressure drops are analyzed in terms of their frictional and inertial components. Pressure-drop data are presented for both tubes and wire mesh regenerators over a range of flow reversal frequencies. The results are discussed with reference to other experimental data and analytical models available in the literature. 10 refs., 6 figs., 2 tabs.

  6. Flexible corrugated cryotransferlines, long term experience at JET and the experience with supercritical helium flow conditions

    E-Print Network [OSTI]

    Obert, W

    1996-01-01T23:59:59.000Z

    Flexible corrugated cryotransferlines, long term experience at JET and the experience with supercritical helium flow conditions

  7. Flexible Corrugated Cryotransferlines, Long Term Experience at JET and the Experience with Supercritical Helium Flow Conditions

    E-Print Network [OSTI]

    Flexible Corrugated Cryotransferlines, Long Term Experience at JET and the Experience with Supercritical Helium Flow Conditions

  8. The gradient flow running coupling with twisted boundary conditions

    E-Print Network [OSTI]

    A. Ramos

    2014-09-04T23:59:59.000Z

    We study the gradient flow for Yang-Mills theories with twisted boundary conditions. The perturbative behavior of the energy density $\\langle E(t)\\rangle$ is used to define a running coupling at a scale given by the linear size of the finite volume box. We compute the non-perturbative running of the pure gauge $SU(2)$ coupling constant and conclude that the technique is well suited for further applications due to the relatively mild cutoff effects of the step scaling function and the high numerical precision that can be achieved in lattice simulations. We also comment on the inclusion of matter fields.

  9. Revisiting Johnson and Jackson boundary conditions for granular flows

    SciTech Connect (OSTI)

    Li, Tingwen; Benyahia, Sofiane

    2012-07-01T23:59:59.000Z

    In this article, we revisit Johnson and Jackson boundary conditions for granular flows. The oblique collision between a particle and a flat wall is analyzed by adopting the classic rigid-body theory and a more realistic semianalytical model. Based on the kinetic granular theory, the input parameter for the partial-slip boundary conditions, specularity coefficient, which is not measurable in experiments, is then interpreted as a function of the particle-wall restitution coefficient, the frictional coefficient, and the normalized slip velocity at the wall. An analytical expression for the specularity coefficient is suggested for a flat, frictional surface with a low frictional coefficient. The procedure for determining the specularity coefficient for a more general problem is outlined, and a working approximation is provided.

  10. On stability condition for bifluid flows with surface tension : application to microfluidics

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    On stability condition for bifluid flows with surface tension : application to microfluidics C immiscible bifluid flows with surface tension are here considered. Since Brackbill, Kothe and Zemach (J mixing dynamics inside microdroplets. Key words: surface tension, curvature, stability condition, bifluid

  11. Method and apparatus for measuring coupled flow, transport, and reaction processes under liquid unsaturated flow conditions

    DOE Patents [OSTI]

    McGrail, Bernard P. (Pasco, WA); Martin, Paul F. (Richland, WA); Lindenmeier, Clark W. (Richland, WA)

    1999-01-01T23:59:59.000Z

    The present invention is a method and apparatus for measuring coupled flow, transport and reaction processes under liquid unsaturated flow conditions. The method and apparatus of the present invention permit distinguishing individual precipitation events and their effect on dissolution behavior isolated to the specific event. The present invention is especially useful for dynamically measuring hydraulic parameters when a chemical reaction occurs between a particulate material and either liquid or gas (e.g. air) or both, causing precipitation that changes the pore structure of the test material.

  12. Smolt Responses to Hydrodynamic Conditions in Forebay Flow Nets of Surface Flow Outlets, 2007

    SciTech Connect (OSTI)

    Johnson, Gary E.; Richmond, Marshall C.; Hedgepeth, J. B.; Ploskey, Gene R.; Anderson, Michael G.; Deng, Zhiqun; Khan, Fenton; Mueller, Robert P.; Rakowski, Cynthia L.; Sather, Nichole K.; Serkowski, John A.; Steinbeck, John R.

    2009-04-01T23:59:59.000Z

    This study provides information on juvenile salmonid behaviors at McNary and The Dalles dams that can be used by the USACE, fisheries resource managers, and others to support decisions on long-term measures to enhance fish passage. We researched smolt movements and ambient hydrodynamic conditions using a new approach combining simultaneous acoustic Doppler current profiler (ADCP) and acoustic imaging device (AID) measurements at surface flow outlets (SFO) at McNary and The Dalles dams on the Columbia River during spring and summer 2007. Because swimming effort vectors could be computed from the simultaneous fish and flow data, fish behavior could be categorized as passive, swimming against the flow (positively rheotactic), and swimming with the flow (negatively rheotactic). We present bivariate relationships to provide insight into fish responses to particular hydraulic variables that engineers might consider during SFO design. The data indicate potential for this empirical approach of simultaneous water/fish measurements to lead to SFO design guidelines in the future.

  13. Preferential flow occurs in unsaturated conditions John R. Nimmo*

    E-Print Network [OSTI]

    classification schemes, but usual consideration of preferential flow includes macropore or fracture flow in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/hyp.8380 786Copyright © 2011 John Wiley

  14. Flow conditions of fresh mortar and concrete in different pipes

    SciTech Connect (OSTI)

    Jacobsen, Stefan, E-mail: stefan.jacobsen@ntnu.n [Norwegian University of Science and Technology, Dept of Structural Engineering, Trondheim (Norway); Haugan, Lars; Hammer, Tor Arne [SINTEF Byggforsk AS Building and Infrastructure, Trondheim (Norway); Kalogiannidis, Evangelos [Norwegian University of Science and Technology, Dept of Structural Engineering, Trondheim (Norway)

    2009-11-15T23:59:59.000Z

    The variation in fresh concrete flow rate over the pipe cross section was investigated on differently coloured and highly flowable concrete mixes flowing through pipes of different materials (rubber, steel, acryl). First, uncoloured (gray) concrete was poured through the pipe and the pipe blocked. Similar but coloured (black) concrete was then poured into the pipe filled with gray concrete, flowing after the gray concrete for a while before being blocked and hardened. The advance of the colouring along the pipe wall (showing boundary flow rate) was observed on the moulded concrete surface appearing after removing the pipe from the hardened concrete. The shapes of the interfaces between uncoloured and coloured concrete (showing variation of flow rate over the pipe cross section) were observed on sawn surfaces of concrete half cylinders cut along the length axes of the concrete-filled pipe. Flow profiles over the pipe cross section were clearly seen with maximum flow rates near the centre of the pipe and low flow rate at the pipe wall (typically rubber pipe with reference concrete without silica fume and/or stabilizers). More plug-shaped profiles, with long slip layers and less variation of flow rate over the cross section, were also seen (typically in smooth acrylic pipes). Flow rate, amount of concrete sticking to the wall after flow and SEM-images of pipe surface roughness were observed, illustrating the problem of testing full scale pumping.

  15. The Effect of Pressure Difference Control on Hydraulic Stability in a Variable Flow Air Conditioning System

    E-Print Network [OSTI]

    Zhang, Z.; Fu, Y.; Chen, Y.

    2006-01-01T23:59:59.000Z

    This paper analyzes the effects of different pressure difference control methods on hydraulic stability in a variable flow air conditioning system when it is applied to different air conditioning water systems. According to control method and water...

  16. Diagnosis of Fracture Flow Conditions with Acoustic Sensing

    E-Print Network [OSTI]

    Martinez, Roberto

    2014-07-10T23:59:59.000Z

    that this turbulent flow can generate sound as fluid flows from the fracture into the well. According to Testud et al. (2009) it is widely known that industry pipe systems, valves, taps and orifices whistle when fluid flows through them. Lacombe et al. (2013... of the fluid downstream of the shear layer (Lacombe et al. 2013). During this process there is a transfer of energy from the fluid moving to vortices that create sound. Poldervaart et al. (1974) illustrated how vortices can act as an acoustic source in Fig...

  17. Module Development and Simulation of the Variable Refrigerant Flow Air Conditioning System under Cooling Conditions in Energyplus

    E-Print Network [OSTI]

    Zhou, Y.; Wu, J.; Wang, R.; Shiochi, S.

    2006-01-01T23:59:59.000Z

    ICEBO2006, Shenzhen, China HVAC Technologies for Energy Efficiency Vol.IV-1-2 Module Development and Simulation of the Variable Refrigerant Flow Air Conditioning System under Cooling Conditions in Energyplus Yanping Zhou Jingyi..., especially for those who ICEBO2006, Shenzhen, China HVAC Technologies for Energy Efficiency Vol.IV-1-2 show some interest about high-efficiency systems like VRF, it becomes of interest to compare the VRF to other systems and evaluate VRF?s performance...

  18. Energy-Saving Design for Pressure Difference Control in Variable Flow Air Conditioning Systems

    E-Print Network [OSTI]

    Chen, Y.; Zhang, Z.

    2006-01-01T23:59:59.000Z

    This paper analyzes energy-saving design for pressure-difference control in a variable flow air conditioning system, including the application of a pressure-difference control valve and the installation position of a pressure-difference transducer...

  19. On stability condition for bifluid flows with surface tension: Application to microfluidics

    E-Print Network [OSTI]

    Frey, Pascal

    On stability condition for bifluid flows with surface tension: Application to microfluidics Ce simulations of microfluidic flows using a Level Set method, namely the exploration of different mixing-vol- umes; Microfluidics; Droplets 1. Introduction Analysis and algorithms derived herein are the result

  20. FLOW CONDITIONING DESIGN IN THICK LIQUID PROTECTION S.G. Durbin

    E-Print Network [OSTI]

    California at San Diego, University of

    issuing downwards from nozzles of thickness (small dimension) = 1 cm into ambient air for Reynolds conditioner was studied. As the flow conditioning element immediately upstream of the nozzle inlet, fine, and that free-surface fluctuations are strongly affected by changes in flow conditioner design, even in the near

  1. Effect of Coal Properties and Operation Conditions on Flow Behavior of Coal Slag in Entrained Flow Gasifiers: A Brief Review

    SciTech Connect (OSTI)

    Wang,Ping; Massoudi, Mehrdad

    2011-01-01T23:59:59.000Z

    Integrated gasification combined cycle (IGCC) is a potentially promising clean technology with an inherent advantage of low emissions, since the process removes contaminants before combustion instead of from flue gas after combustion, as in a conventional coal steam plant. In addition, IGCC has potential for cost-effective carbon dioxide capture. Availability and high capital costs are the main challenges to making IGCC technology more competitive and fully commercial. Experiences from demonstrated IGCC plants show that, in the gasification system, low availability is largely due to slag buildup in the gasifier and fouling in the syngas cooler downstream of the gasification system. In the entrained flow gasifiers used in IGCC plants, the majority of mineral matter transforms to liquid slag on the wall of the gasifier and flows out the bottom. However, a small fraction of the mineral matter (as fly ash) is entrained with the raw syngas out of the gasifier to downstream processing. This molten/sticky fly ash could cause fouling of the syngas cooler. Therefore, it is preferable to minimize the quantity of fly ash and maximize slag. In addition, the hot raw syngas is cooled to convert any entrained molten fly slag to hardened solid fly ash prior to entering the syngas cooler. To improve gasification availability through better design and operation of the gasification process, better understanding of slag behavior and characteristics of the slagging process are needed. Slagging behavior is affected by char/ash properties, gas compositions in the gasifier, the gasifier wall structure, fluid dynamics, and plant operating conditions (mainly temperature and oxygen/carbon ratio). The viscosity of the slag is used to characterize the behavior of the slag flow and is the dominating factor to determine the probability that ash particles will stick. Slag viscosity strongly depends on the temperature and chemical composition of the slag. Because coal has varying ash content and composition, different operating conditions are required to maintain the slag flow and limit problems downstream. This report briefly introduces the IGCC process, the gasification process, and the main types and operating conditions of entrained flow gasifiers used in IGCC plants. This report also discusses the effects of coal ash and slag properties on slag flow and its qualities required for the entrained flow gasifier. Finally this report will identify the key operating conditions affecting slag flow behaviors, including temperature, oxygen/coal ratio, and flux agents.

  2. Fluctuating initial condition and smoothening effect on elliptic and triangular flow

    E-Print Network [OSTI]

    Haque, Md Rihan; Chaudhuri, A K

    2012-01-01T23:59:59.000Z

    In heavy ion collisions, event-by-event fluctuations in participating nucleon positions can lead to triangular flow. Generally, one uses Monte-Carlo Glauber model to obtain the participating nucleon positions. To use in a hydrodynamic model, the positions needs to be smoothened. We study the effect of smoothening of Glauber Monte-Carlo initial conditions on elliptic and triangular flow. It is shown that integrated as well as differential elliptic and triangular flow remain largely unaltered, irrespective of functional form of the smoothening function, or the smoothening parameter

  3. Fluctuating initial condition and smoothening effect on elliptic and triangular flow

    E-Print Network [OSTI]

    Md. Rihan Haque; Victor Roy; A. K. Chaudhuri

    2012-04-13T23:59:59.000Z

    In heavy ion collisions, event-by-event fluctuations in participating nucleon positions can lead to triangular flow. Generally, one uses Monte-Carlo Glauber model to obtain the participating nucleon positions. To use in a hydrodynamic model, the positions needs to be smoothened. We study the effect of smoothening of Glauber Monte-Carlo initial conditions on elliptic and triangular flow. It is shown that integrated as well as differential elliptic and triangular flow remain largely unaltered, irrespective of functional form of the smoothening function, or the smoothening parameter

  4. Artificial boundary conditions for stationary Navier-Stokes flows past bodies in the half-plane

    E-Print Network [OSTI]

    Boeckle, Christoph

    2012-01-01T23:59:59.000Z

    We discuss artificial boundary conditions for stationary Navier-Stokes flows past bodies in the half-plane, for a range of low Reynolds numbers. When truncating the half-plane to a finite domain for numerical purposes, artificial boundaries appear. We present an explicit Dirichlet condition for the velocity at these boundaries in terms of an asymptotic expansion for the solution to the problem. We show a substantial increase in accuracy of the computed values for drag and lift when compared with results for traditional boundary conditions. We also analyze the qualitative behavior of the solutions in terms of the streamlines of the flow. The new boundary conditions are universal in the sense that they depend on a given body only through one constant, which can be determined in a feed-back loop as part of the solution process.

  5. Permeability-dependent propagation of polyacrylamides under near-wellbore flow conditions

    SciTech Connect (OSTI)

    Zitha, P.; Chauveteau, G.; Zaitoun, A. [Inst. Francais du Petrole, Rueil-Malmaison (France)

    1995-11-01T23:59:59.000Z

    A new type of polyacrylamide flow-induced retention has been observed in core experiments simulating near-wellbore flow conditions. The retention is due to the bridging of pore throats by adsorbed macromolecules previously stretched under elongational flow. It occurs in low-to-medium permeability granular packs (up to k = 1,000 mD in the test conditions) and leads to progressive but severe plugging. The present paper shows that polymer placement in the reservoir surrounding the wellbore can be very different from what is predicted from stable values of polymer mobility. In heterogeneous reservoirs, polymer penetration in low-permeability layers is expected to be strongly reduced, thus allowing a deeper penetration into higher permeability zones. The polymer can thus improve reservoir conformance around the wellbore when injected directly through the entire opened interval. Near-wellbore polymer or gel treatments may thus not require zone isolation to be efficient.

  6. Chapter 3 -Basic Water Quality in the Boulder Creek Watershed, Colorado, During High-Flow and Low-Flow Conditions, 2000

    E-Print Network [OSTI]

    Chapter 3 - Basic Water Quality in the Boulder Creek Watershed, Colorado, During High-Flow and Low of the water quality of Boulder Creek, Colorado, during high-flow and low-flow conditions in the year 2000 constituents in Boulder Creek increased after the creek received wastewater effluent. INTRODUCTION Two programs

  7. CO[sub 2] flow patterns under multiphase flow: Heterogeneous field-scale conditions

    SciTech Connect (OSTI)

    Chang, Y.B.; Lim, M.T.; Pope, G.A.; Sepehrnoori, K. (Univ. of Texas, Austin, TX (United States))

    1994-08-01T23:59:59.000Z

    A finite-difference, equation-of-state (EOS), compositional simulator has been used to study CO[sub 2] flooding. First, unstable first-contact-miscible (FCM) displacements were simulated with a fine mesh to investigate the transition from gravity override to viscous fingering. Next, a direct comparison was made for FCM and multiple-contact-miscible (MCM) displacements under the same conditions to investigate effects of phase behavior on the growth of viscous fingers. Then, the effects of gravity, physical dispersion, capillary pressure, phase behavior, and heterogeneity were combined and simulated for CO[sub 2] flooding on a field scale with stochastic permeability fields.

  8. A Convective-like Energy-Stable Open Boundary Condition for Simulations of Incompressible Flows

    E-Print Network [OSTI]

    Dong, Suchuan

    2015-01-01T23:59:59.000Z

    We present a new energy-stable open boundary condition, and an associated numerical algorithm, for simulating incompressible flows with outflow/open boundaries. This open boundary condition ensures the energy stability of the system, even when strong vortices or backflows occur at the outflow boundary. Under certain situations it can be reduced to a form that can be analogized to the usual convective boundary condition. One prominent feature of this boundary condition is that it provides a control over the velocity on the outflow/open boundary. This is not available with the other energy-stable open boundary conditions from previous works. Our numerical algorithm treats the proposed open boundary condition based on a rotational velocity-correction type strategy. It gives rise to a Robin-type condition for the discrete pressure and a Robin-type condition for the discrete velocity on the outflow/open boundary, respectively at the pressure and the velocity sub-steps. We present extensive numerical experiments on...

  9. Pore-Scale Characterization of Biogeochemical Controls on Iron and Uranium Speciation under Flow Conditions

    SciTech Connect (OSTI)

    Pearce, Carolyn I.; Wilkins, Michael J.; Zhang, Changyong; Heald, Steve M.; Fredrickson, Jim K.; Zachara, John M.

    2012-09-17T23:59:59.000Z

    Etched silicon microfluidic pore network models (micromodels) with controlled chemical and redox gradients, mineralogy, and microbiology under continuous flow conditions are used for the incremental development of complex microenvironments that simulate subsurface conditions. We demonstrate the colonization of micromodel pore spaces by an anaerobic Fe(III)-reducing bacterial species (Geobacter sulfurreducens) and the enzymatic reduction of a bioavailable Fe(III) phase within this environment. Using both X-ray Microprobe and X-ray Absorption Spectroscopy, we investigate the combined effects of the precipitated Fe(III) phases and the microbial population on uranium biogeochemistry under flow conditions. Precipitated Fe(III) phases within the micromodel were most effectively reduced in the presence of an electron shuttle (AQDS), and Fe(II) ions adsorbed onto the precipitated mineral surface without inducing any structural change. In the absence of Fe(III), U(VI) was effectively reduced by the microbial population to insoluble U(IV), which was precipitated in discrete regions associated with biomass. In the presence of Fe(III) phases, however, both U(IV) and U(VI) could be detected associated with biomass, suggesting re-oxidation of U(IV) by localized Fe(III) phases. These results demonstrate the importance of the spatial localization of biomass and redox active metals, and illustrate the key effects of pore-scale processes on contaminant fate and reactive transport.

  10. Proton Gradient Regulation 5-Mediated Cyclic Electron Flow under ATP-or Redox-Limited Conditions: A Study of

    E-Print Network [OSTI]

    Proton Gradient Regulation 5-Mediated Cyclic Electron Flow under ATP- or Redox-Limited Conditions.K.N.) The Chlamydomonas reinhardtii proton gradient regulation5 (Crpgr5) mutant shows phenotypic and functional traits discriminate two pathways for CEF and determine their maximum electron flow rates. The PGR5/proton gradient

  11. Low-Flow Liquid Desiccant Air-Conditioning: Demonstrated Performance and Cost Implications

    SciTech Connect (OSTI)

    Kozubal, E.; Herrmann, L.; Deru, M.; Clark, J.; Lowenstein, A.

    2014-09-01T23:59:59.000Z

    Cooling loads must be dramatically reduced when designing net-zero energy buildings or other highly efficient facilities. Advances in this area have focused primarily on reducing a building's sensible cooling loads by improving the envelope, integrating properly sized daylighting systems, adding exterior solar shading devices, and reducing internal heat gains. As sensible loads decrease, however, latent loads remain relatively constant, and thus become a greater fraction of the overall cooling requirement in highly efficient building designs, particularly in humid climates. This shift toward latent cooling is a challenge for heating, ventilation, and air-conditioning (HVAC) systems. Traditional systems typically dehumidify by first overcooling air below the dew-point temperature and then reheating it to an appropriate supply temperature, which requires an excessive amount of energy. Another dehumidification strategy incorporates solid desiccant rotors that remove water from air more efficiently; however, these systems are large and increase fan energy consumption due to the increased airside pressure drop of solid desiccant rotors. A third dehumidification strategy involves high flow liquid desiccant systems. These systems require a high maintenance separator to protect the air distribution system from corrosive desiccant droplet carryover and so are more commonly used in industrial applications and rarely in commercial buildings. Both solid desiccant systems and most high-flow liquid desiccant systems (if not internally cooled) add sensible energy which must later be removed to the air stream during dehumidification, through the release of sensible heat during the sorption process.

  12. Chromium Isotope Fractionation During Reduction of Cr(VI) Under Saturated Flow Conditions

    SciTech Connect (OSTI)

    Jamieson-Hanes, Julia H.; Gibson, Blair D.; Lindsay, Matthew B.J.; Kim, Yeongkyoo; Ptacek, Carol J.; Blowes, David W. (Waterloo); (Kyungpook National University)

    2012-10-25T23:59:59.000Z

    Chromium isotopes are potentially useful indicators of Cr(VI) reduction reactions in groundwater flow systems; however, the influence of transport on Cr isotope fractionation has not been fully examined. Laboratory batch and column experiments were conducted to evaluate isotopic fractionation of Cr during Cr(VI) reduction under both static and controlled flow conditions. Organic carbon was used to reduce Cr(VI) in simulated groundwater containing 20 mg L{sup -1} Cr(VI) in both batch and column experiments. Isotope measurements were performed on dissolved Cr on samples from the batch experiments, and on effluent and profile samples from the column experiment. Analysis of the residual solid-phase materials by scanning electron microscopy (SEM) and by X-ray absorption near edge structure (XANES) spectroscopy confirmed association of Cr(III) with organic carbon in the column solids. Decreases in dissolved Cr(VI) concentrations were coupled with increases in {delta}{sup 53}Cr, indicating that Cr isotope enrichment occurred during reduction of Cr(VI). The {delta}{sup 53}Cr data from the column experiment was fit by linear regression yielding a fractionation factor ({alpha}) of 0.9979, whereas the batch experiments exhibited Rayleigh-type isotope fractionation ({alpha} = 0.9965). The linear characteristic of the column {delta}{sup 53}Cr data may reflect the contribution of transport on Cr isotope fractionation.

  13. Flow and morphological conditions associated with the directional solidification of aqueous ammonium chloride

    SciTech Connect (OSTI)

    Magirl, C.S.; Incropera, F.P.

    1993-01-01T23:59:59.000Z

    Using 27% aq. NH[sub 4]Cl solutions as transparent analog, shadowgraphy and dye injection were used to observe flow and morphology in unidirectional solidification (UDS) from below. Dendritic crystals that form at the cold surface reject lighter, solute-deficient fluid, and instability is shown by finger-type double-diffusive convection. As the mushy two-phase region grows, perturbations at the liquidus interface cause localized remelting and downward development of channels. Solsutal plumes emanate from the channels, and in time, double-diffusive convection layers also form in the melt. When the solution is chilled at the sides as well as at the bottom, conditions are influenced by detachment and settling of crystals from the sidewall and by plumes from slanted channels. When a slow, oscillatory rocking motion is imposed on UDS, the freckle-type segregates in the final cast is suppressed. Within the melt, plumes and double-diffusive convection are eliminated. Inertially induced convection mixes the melt and produces a dense slurry. Although channels are eliminated from the bottom mushy region, overall heat transfer and macrosegregation in the cavity are unaffected by the slow rocking. Numerical simulations qualitatively predict trends in the field variables and provide insights on interdendritic flows and macrosegregation (freckle-, A-type segregates), although its quantitative predictions are hampered by simplifying assumptions.

  14. Flow and morphological conditions associated with the directional solidification of aqueous ammonium chloride. Annual performance report

    SciTech Connect (OSTI)

    Magirl, C.S.; Incropera, F.P.

    1993-01-01T23:59:59.000Z

    Using 27% aq. NH{sub 4}Cl solutions as transparent analog, shadowgraphy and dye injection were used to observe flow and morphology in unidirectional solidification (UDS) from below. Dendritic crystals that form at the cold surface reject lighter, solute-deficient fluid, and instability is shown by finger-type double-diffusive convection. As the mushy two-phase region grows, perturbations at the liquidus interface cause localized remelting and downward development of channels. Solsutal plumes emanate from the channels, and in time, double-diffusive convection layers also form in the melt. When the solution is chilled at the sides as well as at the bottom, conditions are influenced by detachment and settling of crystals from the sidewall and by plumes from slanted channels. When a slow, oscillatory rocking motion is imposed on UDS, the freckle-type segregates in the final cast is suppressed. Within the melt, plumes and double-diffusive convection are eliminated. Inertially induced convection mixes the melt and produces a dense slurry. Although channels are eliminated from the bottom mushy region, overall heat transfer and macrosegregation in the cavity are unaffected by the slow rocking. Numerical simulations qualitatively predict trends in the field variables and provide insights on interdendritic flows and macrosegregation (freckle-, A-type segregates), although its quantitative predictions are hampered by simplifying assumptions.

  15. Virtual Measurement in Pipes, Part 1: Flowing Bottom Hole Pressure Under Multi-Phase Flow and Inclined Wellbore Conditions

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    SPE 30975 Virtual Measurement in Pipes, Part 1: Flowing Bottom Hole Pressure Under Multi-Phase Flow, 163245 SPEUT. Abstract Pressure drop prediction in pipes is an old petroleum engineering problem. There is a long history of attempts to develop empirical correlations to predict the pressure drop in pipes. Some

  16. Assessment of Controlling Processes for Field-Scale Uranium Reactive Transport under Highly Transient Flow Conditions

    SciTech Connect (OSTI)

    Ma, Rui; Zheng, Chunmiao; Liu, Chongxuan; Greskowiak, Janek; Prommer, Henning; Zachara, John M.

    2014-02-13T23:59:59.000Z

    This paper presents the results of a comprehensive model-based analysis of a uranium tracer test conducted at the U.S Department of Energy Hanford 300 Area (300A) IFRC site. A three-dimensional multi-component reactive transport model was employed to assess the key factors and processes that control the field-scale uranium reactive transport. Taking into consideration of relevant physical and chemical processes, the selected conceptual/numerical model replicates the spatial and temporal variations of the observed U(VI) concentrations reasonably well in spite of the highly complex field conditions. A sensitivity analysis was performed to interrogate the relative importance of various processes and factors for reactive transport of U(VI) at the field-scale. The results indicate that multi-rate U(VI) sorption/desorption, U(VI) surface complexation reactions, and initial U(VI) concentrations were the most important processes and factors controlling U(VI) migration. On the other hand, cation exchange reactions, the choice of the surface complexation model, and dual-domain mass transfer processes, which were previously identified to be important in laboratory experiments, played less important roles under the field-scale experimental condition at the 300A site. However, the model simulations also revealed that the groundwater chemistry was relatively stable during the uranium tracer experiment and therefore presumably not dynamic enough to appropriately assess the effects of ion exchange reaction and the choice of surface complexation models on U(VI) sorption and desorption. Furthermore, it also showed that the field experimental duration (16 days) was not sufficiently long to precisely assess the role of a majority of the sorption sites that were accessed by slow kinetic processes within the dual domain model. The sensitivity analysis revealed the crucial role of the intraborehole flow that occurred within the long-screened monitoring wells and thus significantly affected both field-scale measurements and simulated U(VI) concentrations as a combined effect of aquifer heterogeneity and highly dynamic flow conditions. Overall, this study, which provides one of the few detailed and highly data-constrained uranium transport simulations, highlights the difference in controlling processes between laboratory and field scale that prevent a simple direct upscaling of laboratory-scale models.

  17. Flow Components in a NaK Test Loop Designed to Simulate Conditions in a Nuclear Surface Power Reactor

    SciTech Connect (OSTI)

    Polzin, Kurt A.; Godfroy, Thomas J. [NASA Marshall Space Flight Center Propulsion Research and Technology Applications Branch/ER24, MSFC, AL 35812 (United States)

    2008-01-21T23:59:59.000Z

    A test loop using NaK as the working fluid is presently in use to study material compatibility effects on various components that comprise a possible nuclear reactor design for use on the lunar surface. A DC electromagnetic (EM) pump has been designed and implemented as a means of actively controlling the NaK flow rate through the system and an EM flow sensor is employed to monitor the developed flow rate. These components allow for the matching of the flow rate conditions in test loops with those that would be found in a full-scale surface-power reactor. The design and operating characteristics of the EM pump and flow sensor are presented. In the EM pump, current is applied to a set of electrodes to produce a Lorentz body force in the fluid. A measurement of the induced voltage (back-EMF) in the flow sensor provides the means of monitoring flow rate. Both components are compact, employing high magnetic field strength neodymium magnets thermally coupled to a water-cooled housing. A vacuum gap limits the heat transferred from the high temperature NaK tube to the magnets and a magnetically-permeable material completes the magnetic circuit. The pump is designed to produce a pressure rise of 34.5 kPa, and the flow sensor's predicted output is roughly 20 mV at the loop's nominal flow rate of 0.114 m{sup 3}/hr.

  18. Use of an Accurate DNS Particulate Flow Method to Supply and Validate Boundary Conditions for the MFIX Code

    SciTech Connect (OSTI)

    Zhi-Gang Feng

    2012-05-31T23:59:59.000Z

    The simulation of particulate flows for industrial applications often requires the use of two-fluid models, where the solid particles are considered as a separate continuous phase. One of the underlining uncertainties in the use of the two-fluid models in multiphase computations comes from the boundary condition of the solid phase. Typically, the gas or liquid fluid boundary condition at a solid wall is the so called no-slip condition, which has been widely accepted to be valid for single-phase fluid dynamics provided that the Knudsen number is low. However, the boundary condition for the solid phase is not well understood. The no-slip condition at a solid boundary is not a valid assumption for the solid phase. Instead, several researchers advocate a slip condition as a more appropriate boundary condition. However, the question on the selection of an exact slip length or a slip velocity coefficient is still unanswered. Experimental or numerical simulation data are needed in order to determinate the slip boundary condition that is applicable to a two-fluid model. The goal of this project is to improve the performance and accuracy of the boundary conditions used in two-fluid models such as the MFIX code, which is frequently used in multiphase flow simulations. The specific objectives of the project are to use first principles embedded in a validated Direct Numerical Simulation particulate flow numerical program, which uses the Immersed Boundary method (DNS-IB) and the Direct Forcing scheme in order to establish, modify and validate needed energy and momentum boundary conditions for the MFIX code. To achieve these objectives, we have developed a highly efficient DNS code and conducted numerical simulations to investigate the particle-wall and particle-particle interactions in particulate flows. Most of our research findings have been reported in major conferences and archived journals, which are listed in Section 7 of this report. In this report, we will present a brief description of these results.

  19. Thermalization, Isotropization and Elliptic Flow from Nonequilibrium Initial Conditions with a Saturation Scale

    E-Print Network [OSTI]

    Marco Ruggieri; Francesco Scardina; Salvatore Plumari; Vincenzo Greco

    2014-07-09T23:59:59.000Z

    In this article we report on our results about the computation of the elliptic flow of the quark-gluon-plasma produced in relativistic heavy ion collisions, simulating the expansion of the fireball by solving the relativistic Boltzmann equation for the parton distribution function tuned at a fixed shear viscosity to entropy density ratio $\\eta/s$. Our main goal is to put emphasis on the role of a saturation scale in the initial gluon spectrum, which makes the initial distribution far from a thermalized one. We find that the presence of the saturation scale reduces the efficiency in building-up the elliptic flow, even if the thermalization process is quite fast $\\tau_{therm} \\approx 0.8 \\,\\rm fm/c$ and the pressure isotropization even faster $\\tau_{isotr} \\approx 0.3 \\,\\rm fm/c$. The impact of the non-equilibrium implied by the saturation scale manifests for non-central collisions and can modify the estimate of the viscosity respect to the assumption of full thermalization in $p_T$-space. We find that the estimate of $\\eta/s$ is modified from $\\eta/s \\approx 2/4\\pi$ to $\\eta/s \\approx 1/4\\pi$ at RHIC and from $\\eta/s \\approx 3/4\\pi$ to $\\eta/s \\approx 2/4\\pi$ at LHC. We complete our investigation by a study of the thermalization and isotropization times of the fireball for different initial conditions and values of $\\eta/s$ showing how the latter affects both isotropization and thermalization. Lastly, we have seen that the range of values explored by the phase-space distribution function $f$ is such that at $p_T<0.5\\, \\rm GeV$ the inner part of the fireball stays with occupation number significantly larger than unity despite the fast longitudinal expansion, which might suggest the possibility of the formation of a transient Bose-Einstein Condensate.

  20. Effects of mesh density and flow conditioning in simulating 7-pin wire wrapped fuel pins.

    SciTech Connect (OSTI)

    Smith, J. G.; Babin, B. R.; Pointer, W. D.; Fischer, P. F. (Mathematics and Computer Science); ( NE); (Kansas State Univ.)

    2008-01-01T23:59:59.000Z

    In response to the goals outlined by the U.S. Department of Energy's Global Nuclear Energy Partnership program, Argonne National Laboratory has initiated an effort to create an integrated multi-physics multi-resolution thermal hydraulic simulation tool package for the evaluation of nuclear power plant design and safety. As part of this effort, the applicability of a variety of thermal hydraulic analysis methods for the prediction of heat transfer and fluid dynamics in the wire-wrapped fuel-rod bundles found in a fast reactor core is being evaluated. The work described herein provides an initial assessment of the capabilities of the general purpose commercial computational fluid dynamics code Star-CD for the prediction of fluid dynamic characteristics in a wire wrapped fast reactor fuel assembly. A 7-pin wire wrapped fuel rod assembly based on the dimensions of fuel elements in the concept Advanced Burner Test Reactor [1] was simulated for different mesh densities and domain configurations. A model considering a single axial span of the wire wrapped fuel assembly was initially used to assess mesh resolution effects. The influence of the inflow/outflow boundary conditions on the predicted flow fields in the single-span model were then investigated through comparisons with the central span region of models which included 3 and 5 spans. The change in grid refinement had minimal impact on the inter-channel exchange within the assembly resulting in roughly a 5 percent maximum difference. The central span of the 3-span and 5-span cases exhibits much higher velocities than the single span case,, with the largest deviation (15 to 20 percent) occurring furthest away from the wire spacer grids in the higher velocity regions. However, the differences between predicted flow fields in the 3-span and 5-span models are minimal.

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

    E-Print Network [OSTI]

    Priezjev, Nikolai V

    2012-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Nikolai V. Priezjev

    2012-08-27T23:59:59.000Z

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

  3. Second order adaptive boundary conditions for exterior flow problems: non-symmetric stationary flows in two dimensions

    E-Print Network [OSTI]

    called "artificial boundary conditions" to replace the boundary conditions at infinity. To solve this problem we construct -- by combining results from dynamical systems theory with matched asymptotic field depending explicitly on drag and lift and describing the solution to second and dominant third

  4. Sensor Fish Characterization of Fish Passage Conditions through John Day Dam Spillbay 20 with a Modified Flow Deflector

    SciTech Connect (OSTI)

    Duncan, Joanne P.

    2011-04-29T23:59:59.000Z

    Fish passage conditions over a modified deflector in Spillbay 20 at John Day Dam were evaluated by Pacific Northwest National Laboratory for the U.S. Army Corps of Engineers (USACE), Portland District, using Sensor Fish devices. The objectives of the study were to describe and compare passage exposure conditions at two spill discharges, 2.4 and 4.0 thousand cubic feet per second (kcfs), identifying potential fish injury regions within the routes, and to evaluate a low-tailwater condition at the 2.4-kcfs discharge. The study was performed in April 2010 concurrent with HI-Z balloon-tag studies by Normandeau Associates, Inc. Sensor Fish data were analyzed to estimate 1) exposure conditions, particularly exposure to severe collision and shear events; 2) differences in passage conditions between treatments; and 3) relationships to live-fish injury and mortality data estimates. Nearly all Sensor Fish significant events were classified as collisions; the most severe occurred at the gate, on the spillbay chute, or at the deflector transition. Collisions in the gate region were observed only during the 2.4-kcfs discharge, when the tainter gate was open 1.2 ft. One shear event was observed during the evaluation, occurring at the deflector transition during passage at the 2.4-kcfs discharge at low tailwater. Flow quality, computed using the Sensor Fish turbulence index, was best for passage at the low-flow low-tailwater condition as well. The worst flow quality was observed for the 4.0-kcfs test condition. Contrasting the passage exposure conditions, the 2.4-kcfs low-tailwater treatment would be most deleterious to fish survival and well-being.

  5. Groundwater flow and salt transport in a subterranean estuary2 driven by intensified wave conditions3

    E-Print Network [OSTI]

    Candea, George

    1 Groundwater flow and salt transport in a subterranean estuary2 driven by intensified wave, Western University, London, Canada.6 Email: crobinson@eng.uwo.ca7 b National Centre for Groundwater A numerical study, based on a density-dependent variably saturated groundwater flow model,26 was conducted

  6. Passive Acoustic Detection of Wind Turbine In-Flow Conditions for Active Control and Optimization

    SciTech Connect (OSTI)

    Murray, Nathan E.

    2012-03-12T23:59:59.000Z

    Wind is a significant source of energy; however, the human capability to produce electrical energy still has many hurdles to overcome. One of these is the unpredictability of the winds in the atmospheric boundary layer (ABL). The ABL is highly turbulent in both stable and unstable conditions (based on the vertical temperature profile) and the resulting fluctuations can have a dramatic impact on wind turbine operation. Any method by which these fluctuations could be observed, estimated, or predicted could provide a benefit to the wind energy industry as a whole. Based on the fundamental coupling of velocity fluctuations to pressure fluctuations in the nearly incompressible flow in the ABL, This work hypothesizes that a ground-based array of infrasonic pressure transducers could be employed to estimate the vertical wind profile over a height relevant for wind turbines. To analyze this hypothesis, experiments and field deployments were conducted. Wind tunnel experiments were performed for a thick turbulent boundary layer over a neutral or heated surface. Surface pressure and velocity probe measurements were acquired simultaneously. Two field deployments yielded surface pressure data from a 49 element array. The second deployment at the Reese Technology Center in Lubbock, TX, also included data from a smaller aperture, 96-element array and a 200-meter tall meteorological tower. Analysis of the data successfully demonstrated the ability to estimate the vertical velocity profile using coherence data from the pressure array. Also, dynamical systems analysis methods were successful in identifying and tracking a gust type event. In addition to the passive acoustic profiling method, this program also investigated a rapid response Doppler SODAR system, the optimization of wind turbine blades for enhanced power with reduced aeroacoustic noise production, and the implementation of a wireless health monitoring system for the wind turbine blades. Each of these other objectives was met successfully. The use of phase unwrapping applied to SODAR data was found to yield reasonable results for per-pulse measurements. A health monitoring system design analysis was able to demonstrate the ability to use a very small number of sensors to monitor blade health based on the blade's overall structural modes. Most notable was the development of a multi-objective optimization methodology that successfully yielded an aerodynamic blade design that produces greater power output with reduced aerodynamic loading noise. This optimization method could be significant for future design work.

  7. 23.11.2014bo Akademi Univ -Thermal and Flow Engineering Piispankatu 8, 20500 Turku 1/36 7. Air conditioning, cooling towers

    E-Print Network [OSTI]

    Zevenhoven, Ron

    23.11.2014Ĺbo Akademi Univ - Thermal and Flow Engineering Piispankatu 8, 20500 Turku 1/36 7. Air conditioning, cooling towers Ron Zevenhoven Ĺbo Akademi University Thermal and Flow Engineering Laboratory Engineering Piispankatu 8, 20500 Turku 2/36 7.1 Humid air #12;23.11.2014 Ĺbo Akademi Univ - Thermal and Flow

  8. Visualization of flow boiling in an annular heat exchanger under reduced gravity conditions

    E-Print Network [OSTI]

    Westheimer, David Thomas

    2000-01-01T23:59:59.000Z

    This work examines the effects of gravitational acceleration on the flow boiling process. A test facility focusing on an annular heat exchanger was designed, built out of borosilicate glass, and flown on NASA's KC-135 reduced gravity airplane...

  9. Vertical Flow Dynamics in Kelp Forests: Implications for Nutrient Uptake, Condition and Survival

    E-Print Network [OSTI]

    Edwards, Matthew S.

    2008-01-01T23:59:59.000Z

    change and ENSO impacts on kelp forests. As yet, we areVertical Flow Dynamics in Kelp Forests: Implications forof ocean waves on giant kelp fronds results in the vertical

  10. Nonlocal and localized analyses of conditional mean transient flow in bounded, randomly heterogeneous

    E-Print Network [OSTI]

    Tartakovsky, Daniel M.

    TERMS: 1829 Hydrology: Groundwater hydrology; 1869 Hydrology: Stochastic processes; 3210 Mathematical Geophysics: Modeling; 3230 Mathematical Geophysics: Numerical solutions; KEYWORDS: transient flow.1029/2003WR002099. 1. Introduction [2] Hydraulic parameters vary randomly in space and are therefore often

  11. Two-phase stratified flow regime transition analysis for low gravity conditions

    E-Print Network [OSTI]

    Miller, Kathryn M.

    1990-01-01T23:59:59.000Z

    the effect of the gas and liquid mass flow rates, fluid properties, pipe diameter, angle of pipe inclination, and gravity. Five basic flow regimes were considered: smooth stratified, wavy stratified, intermittent (slug and plug), annular with dispersed... Numerical Solution The premise used in this work for solving for the transition boundary is based on the assumption that the transition from the stratified regime to some other regime will occur when a very small wave exists on the surface of the liquid...

  12. Ice stream basal conditions from block-wise surface data inversion and simple regression models of ice stream flow: Application to

    E-Print Network [OSTI]

    Boyce, C. Kevin

    Ice stream basal conditions from block-wise surface data inversion and simple regression models of ice stream flow: Application to Bindschadler Ice Stream O. V. Sergienko,1 R. A. Bindschadler,2 P. L; published 4 December 2008. [1] Widespread basal conditions controlling ice stream flows are still beyond

  13. Influence of initial conditions on turbulence and mixing in Richtmyer-Meshkov flows in presence of re-shock

    SciTech Connect (OSTI)

    Balasubramanian, Sridhar [Los Alamos National Laboratory; Prestridge, Katherine P [Los Alamos National Laboratory; Orlicz, Gregory C [Los Alamos National Laboratory; Balasubramaniam, Balakumar J [Los Alamos National Laboratory

    2010-11-15T23:59:59.000Z

    The study of influence of initial conditions [amplitude ({delta}) and wavelength ({lambda}) of perturbations] on variable-density flows stems from the the recent work done by Dimonte et at. 2004, Miles et al. 2005 and Balakumar et al. 2008a, where it was shown that both Richtmyer-Meshkov (R-M) and Rayleigh-Taylor (R-T) turbulent flows are not truly self similar and have a strong initial conditions dependence on turbulence transport and mixing. However, so far most of the work on this topic has been numerical studies which suggest that for multi-mode systems, the emergence of a regime of self-similar instability growth independent of the initial conditions does not occur. Experimental evidence is needed to verify this theory. Thus, the present work focuses on conducting an experimental study at moderate Mach number (Ma = 1.2) to understand the effects of multi-mode perturbations of the shocked interface on instability growth rate and mixing for R-M flows, which are important mechanisms in inertial confinement fusion reactions, supernovae, combustion and general fluid mixing processes. The ongoing 3-D numerical simulations using ILES will be used for validation of our experimental results. The experiments to study R-M turbulence and mixing are carreid out at the Los Alamos Gas Shock Tube facility shown in Figure I and described in detail in Balakumar et al. 2008b. A heavy gas curtain of SF{sub 6}, surrounded on both sides by ambient air, representing a light/heavy/light interface is flowed through a varicose nozzle (shown in Figure 1c). This initial interface is then accelerated by a Mach 1.2 shock, generated in the driver section. Simultaneous Particle Image Velocimetry (PIV) and Planar Laser Induced Fluorescence (PLIF) diagnostics are used to characterize the initial conditions and also image the evolving flow to measure instantaneous velocity and density fields. The evolving structures are re-shocked at various times using a moveable reflecting wall to study the initial condition effects on turbulence and mixing. Mean flow fields are averaged from an ensemble of experiments whose initial density fields correlate to within 97% of each other. From the mean field, the fluctuating quantities are determined, and the density self-correlations and density-velocity correlations are calculated.

  14. Susceptibility and predictability of conditions for preferential flow Zhi Wang1 and Jan Feyen

    E-Print Network [OSTI]

    Wang, Zhi "Luke"

    Institute for Land and Water Management, Katholieke Universiteit Leuven, Leuven, Belgium Coen J. Ritsema DLO Winand Staring Centre for Integrated Land, Soil and Water Research, Wageningen, Netherlands Abstract unstable preferen- tial flow) in porous media affects the efficiency of oil recovery from a reservoir

  15. Real time monitoring of multiple wells flowing under pseudosteady state condition by using Kalman filtering

    E-Print Network [OSTI]

    Jacob, Suresh

    2002-01-01T23:59:59.000Z

    This work develops a method for the real time monitoring of well performance by using Kalman filtering. A system of two or more wells draining the same reservoir under pseudo steady state condition is monitored simultaneously to estimate both...

  16. Numerical simulation of the flow over a coastal structure in depth-limited conditions

    E-Print Network [OSTI]

    Ginting, Victor Eralingga

    1998-01-01T23:59:59.000Z

    of detailed measurements of irregular wave transformation in front of the structure in depth-limited conditions. The second data set consists of several test runs to study the irregular wave reflection and runup on the coastal structure in depth...

  17. Comparison of in-cylinder scavenging flows in a two-stroke cycle engine under motored and fired conditions

    SciTech Connect (OSTI)

    Miles, P.C.; Green, R.M.; Witze, P.O.

    1994-06-01T23:59:59.000Z

    The in-cylinder flow field of a loop-scavenged, two-stroke engine has been characterized using laser Doppler velocimetry. The radial component of gas velocity was measured along the axis of the cylinder for both motored and fired operation. Measurements were obtained under conditions simulating both crankcase and external blower driven scavenging. Mean profiles of the radial velocity show marked differences in the global flow structure between motored and fired operation for both scavenging methods. These differences persist throughout the scavenging process and survive compression of the fresh charge. Root mean square (rms) velocity fluctuations near TDC were also determined, and significant differences between motored and fired operation are observed. The rms fluctuations are found to correlate well with the mean shear during compression.

  18. Proper initial conditions for the lubrication model of the flow of a thin film of fluid

    E-Print Network [OSTI]

    S. A. Suslov; A. J. Roberts

    1998-04-08T23:59:59.000Z

    A lubrication model describes the dynamics of a thin layer of fluid spreading over a solid substrate. But to make forecasts we need to supply correct initial conditions to the model. Remarkably, the initial fluid thickness is not the correct initial thickness for the lubrication model. Theory recently developed in \\cite{Roberts89b,Roberts97b} provides the correct projection of initial conditions onto a model of a dynamical system. The correct projection is determined by requiring that the model's solution exponentially quickly approaches that of the actual fluid dynamics. For lubrication we show that although the initial free surface shape contributes the most to the model's initial conditions, the initial velocity field is also an influence. The projection also gives a rationale for incorporating miscellaneous small forcing effects into the lubrication model; gravitational forcing is given as one example.

  19. DNS of vertical plane channel flow with finite-size particles: Voronoi analysis, acceleration statistics and particle-conditioned averaging

    E-Print Network [OSTI]

    Garcia-Villalba, Manuel; Uhlmann, Markus

    2012-01-01T23:59:59.000Z

    We have performed a direct numerical simulation of dilute turbulent particulate flow in a vertical plane channel, fully resolving the phase interfaces. The flow conditions are the same as those in the main case of "Uhlmann, M., Phys. Fluids, vol. 20, 2008, 053305", with the exception of the computational domain length which has been doubled in the present study. The statistics of flow and particle motion are not significantly altered by the elongation of the domain. The large-scale columnar-like structures which had previously been identified do persist and they are still only marginally decorrelated in the prolonged domain. Voronoi analysis of the spatial particle distribution shows that the state of the dispersed phase can be characterized as slightly more ordered than random tending towards a homogeneous spatial distribution. It is also found that the p.d.f.'s of Lagrangian particle accelerations for wall-normal and spanwise directions follow a lognormal distribution as observed in previous experiments of ...

  20. Low-Flow Liquid Desiccant Air Conditioning: General Guidance and Site Considerations

    SciTech Connect (OSTI)

    Kozubal, E.; Herrmann, L.; Deru, M.; Clark, J.

    2014-09-01T23:59:59.000Z

    Dehumidification or latent cooling in buildings is an area of growing interest that has been identified as needing more research and improved technologies for higher performance. Heating, ventilating, and air-conditioning (HVAC) systems typically expend excessive energy by using overcool-and-reheat strategies to dehumidify buildings. These systems first overcool ventilation air to remove moisture and then reheat the air to meet comfort requirements. Another common strategy incorporates solid desiccant rotors that remove moisture from the air more efficiently; however, these systems increase fan energy consumption because of the high airside pressure drop of solid desiccant rotors and can add heat of absorption to the ventilation air. Alternatively, liquid desiccant air-conditioning (LDAC) technology provides an innovative dehumidification solution that: (1) eliminates the need for overcooling and reheating from traditional cooling systems; and (2) avoids the increased fan energy and air heating from solid desiccant rotor systems.

  1. Application of convolution and average pressure approximation for solving non-linear flow problems. constant pressure inner boundary condition for gas flow

    E-Print Network [OSTI]

    Zhakupov, Mansur

    2006-08-16T23:59:59.000Z

    properties are specifically taken as implicit functions of pressure, temperature, and composition) are particularly challenging because the diffusivity equation for the "real gas" flow case is strongly non-linear. Whereas different methods exist which allow...

  2. Application of convolution and average pressure approximation for solving non-linear flow problems. constant pressure inner boundary condition for gas flow 

    E-Print Network [OSTI]

    Zhakupov, Mansur

    2006-08-16T23:59:59.000Z

    The accurate description of fluid flow through porous media allows an engineer to properly analyze past behavior and predict future reservoir performance. In particular, appropriate mathematical models which describe fluid ...

  3. WATER-QUALITY CONDITIONS DURING LOW FLOW IN THE LOWER YOUGHIOGHENY RIVER BASIN, PENNSYLVANIA, OCTOBER 5-7, 1998

    SciTech Connect (OSTI)

    James I. Sams, III, Karl T. Schroeder; Terry E. Ackman; J. Kent Crawford; Kim L. Otto

    2001-01-01T23:59:59.000Z

    In October 1998, a chemical synoptic survey was conducted by the U.S. Geological Survey, in cooperation with the U.S. Department of Energy, National Energy Technology Laboratory, in the Lower Youghiogheny River Basin in Pennsylvania to give a snap-shot of present (1998) water quality during low-flow conditions. Water samples from 38 sites--12 mainstem sites, 22 tributaries, and 4 mine discharges that discharge directly to the Youghiogheny River--were used to identify sources of contaminants from mining operations. Specific conductance, water temperature, pH, and dissolved oxygen were measured in the field at each site and concentrations of major ions and trace elements were measured in the laboratory. Unaccounted for gains and losses in streamflow were measured during the study. Unaccounted for losses in streamflow might be attributed to water loss through streambed fractures. Extensive mine tunnels are present in the basin and loss of water to these tunnels seems likely. Unaccounted for gains in streamflow may be from unmeasured tributaries or surface seeps, but most of the gains are suspected to come from artesian flow through fractures in the streambed from underground mine pools. Influent flows of rust-colored water were noted in some river sections. The pH values for all the samples collected during this survey were above 5.8, and most (33 of 38 samples) were above 7.0. Samples from the four mine-discharge sites also had pH values between 6.3 and 6.7. The lowest pH (5.8) was in a tributary, Galley Run. All 38 sampling sites had net alkalinity. The alkalinity load in the Youghiogheny River increased between Connellsville and McKeesport from 35 to 79 tons per day. Above Smithton, the measured alkalinity load in the Lower Youghiogheny River agreed well with the estimated alkalinity load. Below Smithton, measured alkalinity loads in the Lower Youghiogheny River are greater than calculated loads, resulting in unaccounted for gains in alkalinity. These gains are believed to be from seeps in the streambed. Approximately one-third of the load of total alkalinity in the Youghiogheny River at McKeesport is attributed to Sewickley Creek, which contributes 14 tons per day. Sulfate concentrations in the Youghiogheny River steadily increase from 33 milligrams per liter at Connellsville to 77 milligrams per liter near McKeesport. The measured concentrations of sulfate exceeded Pennsylvania water-quality standards at four tributary sites (Galley Run, Hickman Run, Sewickley Creek, and Gillespie Run) and all four mine-discharge sites but not at any main-stem sites. A large increase in sulfate load between West Newton and Sutersville can be attributed almost entirely to the contribution from Sewickley Creek (49 tons per day). Approximately 25 percent of the load measured between Connellsville and McKeesport is unaccounted for. These gains are believed to be from seeps in the streambed from underground mine pools. Similar patterns also were observed for loads of sodium, calcium, and magnesium. Unmeasured inputs from mine rainage are believed to be the source of these loads. Elevated concentrations (above background levels) of chemicals associated with drainage from coal-mining operations were measured in samples from tributaries, especially from Galley Run, Gillespie Run, and Sewickley Creek, and from the mine-discharge sites. The synoptic survey conducted for this study was successful in identifying generalized reaches of the Youghiogheny River where unaccounted for loads of constituents associated with mining activities are entering the river. However, the survey was not able to pinpoint the location of these loads. Remote-sensing techniques, such as thermal infrared imaging by the National Energy Technology Laboratory, could be useful for determining the precise locations of these inputs.

  4. The effect of velocity boundary conditions on the heat transfer and flow topology in two-dimensional Rayleigh-B\\'enard convection

    E-Print Network [OSTI]

    van der Poel, Erwin P; Verzicco, Roberto; Lohse, Detlef

    2015-01-01T23:59:59.000Z

    The effect of various velocity boundary condition is studied in two-dimensional Rayleigh-B\\'enard convection. Combinations of no-slip, stress-free and periodic boundary conditions are used on both the sidewalls and the horizontal plates. For the studied Rayleigh numbers Ra between $10^8$ and $10^{11}$ the heat transport is lower for $\\Gamma = 0.33$ than for $\\Gamma = 1$ in case of no-slip sidewalls. This is surprisingly opposite for stress-free sidewalls, where the heat transport increases for lower aspect-ratio. In wider cells the aspect-ratio dependence is observed to disappear for $\\text{Ra} \\ge 10^{10}$. Two distinct flow types with very different dynamics can be seen, mostly dependent on the plate velocity boundary condition, namely roll-like flow and horizontal zonal flow, which have a substantial effect on the dynamics and heat transport in the system. The predominantly horizontal zonal flow suppresses heat flux and is observed for stress-free and asymmetric plates. Low aspect-ratio periodic sidewall s...

  5. Climatological conditions for the subpolar North Atlantic during the field campaign of the Greenland Flow Distortion Experiment

    E-Print Network [OSTI]

    Pickart, Robert S.

    of the Greenland Flow Distortion Experiment G.W.K. Moore Department of Physics University of Toronto R.S. Pickart January 21, 2009 #12; 2 Abstract: Due to its high topography, Greenland results in significant to help document this flow distortion as part of the international research project called the Greenland

  6. A three-dimensional numerical model of predevelopment conditions in the Death Valley regional ground-water flow system, Nevada and California

    SciTech Connect (OSTI)

    D'Agnese, F.A.; O'Brien, G.M.; Faunt, C.C.; Belcher, W.R.; San Juan, Carma

    2002-11-22T23:59:59.000Z

    In the early 1990's, two numerical models of the Death Valley regional ground-water flow system were developed by the U.S. Department of Energy. In general, the two models were based on the same basic hydrogeologic data set. In 1998, the U.S. Department of Energy requested that the U.S. Geological Survey develop and maintain a ground-water flow model of the Death Valley region in support of U.S. Department of Energy programs at the Nevada Test Site. The purpose of developing this ''second-generation'' regional model was to enhance the knowledge and understanding of the ground-water flow system as new information and tools are developed. The U.S. Geological Survey also was encouraged by the U.S. Department of Energy to cooperate to the fullest extent with other Federal, State, and local entities in the region to take advantage of the benefits of their knowledge and expertise. The short-term objective of the Death Valley regional ground-water flow system project was to develop a steady-stat e representation of the predevelopment conditions of the ground-water flow system utilizing the two geologic interpretations used to develop the previous numerical models. The long-term objective of this project was to construct and calibrate a transient model that simulates the ground-water conditions of the study area over the historical record that utilizes a newly interpreted hydrogeologic conceptual model. This report describes the result of the predevelopment steady-state model construction and calibration.

  7. Electron Heating by the Ion Cyclotron Instability in Collisionless Accretion Flows. II. Electron Heating Efficiency as a Function of Flow Conditions

    E-Print Network [OSTI]

    Sironi, Lorenzo

    2014-01-01T23:59:59.000Z

    In the innermost regions of low-luminosity accretion flows, including Sgr A* at the center of our Galaxy, the frequency of Coulomb collisions is so low that the plasma is two-temperature, with the ions substantially hotter than the electrons. This paradigm assumes that Coulomb collisions are the only channel for transferring the ion energy to the electrons. In this work, the second of a series, we assess the efficiency of electron heating by ion velocity-space instabilities in collisionless accretion flows. The instabilities are seeded by the pressure anisotropy induced by magnetic field amplification, coupled to the adiabatic invariance of the particle magnetic moments. Using two-dimensional (2D) particle-in-cell (PIC) simulations, we showed in Paper I that if the electron-to-ion temperature ratio is < 0.2, the ion cyclotron instability is the dominant mode for values of ion beta_i ~ 5-30 (here, beta_i is the ratio of ion thermal pressure to magnetic pressure), as appropriate for the midplane of low-lumin...

  8. Investigating the changes in matrix and fracture properties and fluid flow under different stress-state conditions

    E-Print Network [OSTI]

    Muralidharan, Vivek

    2004-11-15T23:59:59.000Z

    pressure of 500 psi................................................................33 3.16 The average flow rate comparison between laboratory and simulation results at 5 cc/min and each different overburden pressure.............................35... .........................................................................................................87 xiii FIGURE Pa ge 5.28 Sample scans taken along the length of the core with 500 psi overburden pressure...

  9. Electrochemical study of multi-electrode microbial fuel cells under fed-batch and continuous flow conditions

    E-Print Network [OSTI]

    Electrochemical study of multi-electrode microbial fuel cells under fed-batch and continuous flow November 2013 Available online 18 December 2013 Keywords: Multi-electrode Microbial fuel cells Hydraulic connected microbial fuel cells (MFCs) was compared with the reactors operated using individual electrical

  10. Adsorption of Trace Levels of Arsenic from Aqueous Solutions by Conditioned Layered Double Hydroxides: Batch and Flow

    E-Print Network [OSTI]

    Southern California, University of

    Adsorption of Trace Levels of Arsenic from Aqueous Solutions by Conditioned Layered Double to humans. The focus of the present work is to do a systematic study of the adsorption of As by conditioned the dissolution observed with uncalcined and calcined LDH3. The adsorption rates and isotherms have been

  11. Step-flow anisotropy of the m-plane GaN (1100) grown under nitrogen-rich conditions by plasma-assisted molecular beam epitaxy

    SciTech Connect (OSTI)

    Sawicka, Marta; Siekacz, Marcin; Skierbiszewski, Czeslaw [Institute of High Pressure Physics, Polish Academy of Sciences, Sokolowska 29/37, PL-01-142 Warszawa (Poland); TopGaN Ltd., Sokolowska 29/37, PL-01-142 Warszawa (Poland); Turski, Henryk; Krysko, Marcin; DziePcielewski, Igor; Grzegory, Izabella [Institute of High Pressure Physics, Polish Academy of Sciences, Sokolowska 29/37, PL-01-142 Warszawa (Poland); Smalc-Koziorowska, Julita [Institute of High Pressure Physics, Polish Academy of Sciences, Sokolowska 29/37, PL-01-142 Warszawa (Poland); TopGaN Ltd., Sokolowska 29/37, PL-01-142 Warszawa (Poland); Warsaw University of Technology, Faculty of Material Science and Engineering, Woloska 141, PL-02-507 Warszawa (Poland)

    2011-06-15T23:59:59.000Z

    The homoepitaxial growth of m-plane (1100) GaN was investigated by plasma-assisted molecular beam epitaxy under nitrogen-rich conditions. The surface morphologies as a function of sample miscut were studied, providing evidence for a strong growth anisotropy that is a consequence of the anisotropy of Ga adatom diffusion barriers on the m-plane surface recently calculated ab initio[Lymperakis and Neugebauer, Phys. Rev. B 79, 241308(R) (2009)]. We found that substrate miscut toward [0001] implies a step flow toward <1126> while substrate miscut toward [0001] causes formation of atomic steps either perpendicular or parallel to the [0001] direction, under N-rich conditions at 730 deg C. We describe the growth conditions for achieving atomically flat m-plane GaN layers with parallel atomic steps.

  12. Experimental analysis of the vorticity and turbulent flow dynamics of a pitching airfoil at realistic flight (helicopter) conditions

    E-Print Network [OSTI]

    Sahoo, Dipankar

    2008-10-10T23:59:59.000Z

    staff members, Karen Knabe, Andrea Loggins, and Colleen Leatherman for their help with official paper work which saved me a lot of time. I extend my gratitude to all employees at the Oran W Nicks Low Speed Wind Tunnel for their valuable assistance... ..................................................... 31 4.1 Oran Nicks Low-Speed Wind Tunnel .................................................. 31 4.1.1 The DSF Inserts ..................................................................... 32 4.1.2 Tunnel Flow...

  13. A computational study of ultrasonic film thickness measurements in annular two-phase flows under microgravity conditions

    E-Print Network [OSTI]

    Pautz, Shawn Daniel

    1995-01-01T23:59:59.000Z

    wave equation: 11 V p(x, t) ? z z' = S(x, t), o p(x, t) c'(x) cl' (2. 1) where p(x, t) is the sound pressure, c(x) is the sound speed of propagation, and S(x, t) is a time-dependent source. Equation (2. 1) is derived from conservation laws... of level liquid film with epoxy layer, 2D approximation . . . . . 55 4. 13 Return signal of level liquid film with epoxy layer, 2D approximation . . . . . . . . . . . . . 56 5. 1 Maximum return amplitude vs. interfacial slope for smooth annular flow...

  14. A study of the rate of dissolution of rock salt in drilling mud flowing under down hole conditions 

    E-Print Network [OSTI]

    Forsyth, Jackie Lee

    1990-01-01T23:59:59.000Z

    , at this and higher temperatures, the flow rate was determined from the total volume displaced and the total run time, and the salt dissolution rate was determined primarily from the weight loss measurements. MATERIALS The mud used in the tests was supplied..., the transfer of a full reservoir of mud was timed to estimate the flowrate for some of the tests at 375 F [191 Cj. Again, the polymer was tested only at room temperature. 16 DATA The rate of salt dissolution per unit area of salt surface (R...

  15. TOUGHREACT Version 2.0: A simulator for subsurface reactive transport under non-isothermal multiphase flow conditions

    SciTech Connect (OSTI)

    Xu, T.; Spycher, N.; Sonnenthal, E.; Zhang, G.; Zheng, L.; Pruess, K.

    2010-08-01T23:59:59.000Z

    TOUGHREACT is a numerical simulation program for chemically reactive non-isothermal flows of multiphase fluids in porous and fractured media, and was developed by introducing reactive chemistry into the multiphase fluid and heat flow simulator TOUGH2 V2. The first version of TOUGHREACT was released to the public through the U.S. Department of Energy's Energy Science and Technology Software Center (ESTSC) in August 2004. It is among the most frequently requested of ESTSC's codes. The code has been widely used for studies in CO{sub 2} geological sequestration, nuclear waste isolation, geothermal energy development, environmental remediation, and increasingly for petroleum applications. Over the past several years, many new capabilities have been developed, which were incorporated into Version 2 of TOUGHREACT. Major additions and improvements in Version 2 are discussed here, and two application examples are presented: (1) long-term fate of injected CO{sub 2} in a storage reservoir and (2) biogeochemical cycling of metals in mining-impacted lake sediments.

  16. Sufficient condition for a finite-time singularity in a high-symmetry Euler flow: Analysis and statistics

    E-Print Network [OSTI]

    Ng, Chung-Sang

    City, Iowa 52242 Received 20 March 1995 A sufficient condition is obtained for the development that for fixed total energy, pxxxx is predominantly positive with the average value growing with the numbers spontaneously, dissipa- tion intervenes, and the dynamical balance between the two processes determines

  17. Three-dimensional analysis of future groundwater flow conditions and contaminant plume transport in the Hanford Site unconfined aquifer system: FY 1996 and 1997 status report

    SciTech Connect (OSTI)

    Cole, C.R.; Wurstner, S.K.; Williams, M.D.; Thorne, P.D.; Bergeron, M.P.

    1997-12-01T23:59:59.000Z

    A three-dimensional numerical model of groundwater flow and transport, based on the Coupled Fluid Energy, and Solute Transport (CFEST) code, was developed for the Hanford Site to support the Hanford Groundwater Project (HGWP), managed by Pacific Northwest National Laboratory. The model was developed to increase the understanding and better forecast the migration of several contaminant plumes being monitored by the HGWP, and to support the Hanford Site Composite Analysis for low-level waste disposal in the 200-Area Plateau. Recent modeling efforts have focused on continued refinement of an initial version of the three-dimensional model developed in 1995 and its application to simulate future transport of selected contaminant plumes in the aquifer system. This version of the model was updated using a more current version of the CFEST code called CFEST96. Prior to conducting simulations of contaminant transport with the three-dimensional model, a previous steady-state, two-dimensional model of the unconfined aquifer system was recalibrated to 1979 water-table conditions with a statistical inverse method implemented in the CFEST-INV computer code. The results of the recalibration were used to refine the three-dimensional conceptual model and to calibrate it with a conceptualization that preserves the two-dimensional hydraulic properties and knowledge of the aquifer`s three-dimensional properties for the same 1979 water-table conditions. The transient behavior of the three-dimensional flow model was also calibrated by adjusting model storage properties (specific yield) until transient water-table predictions approximated observed water-table elevations between 1979 and 1996.

  18. The microcanonical thermodynamics of finite systems: The microscopic origin of condensation and phase separations; and the conditions for heat flow from lower to higher temperatures

    E-Print Network [OSTI]

    D. H. E. Gross; J. F. Kenney

    2005-03-24T23:59:59.000Z

    Microcanonical thermodynamics allows the application of statistical mechanics both to finite and even small systems and also to the largest, self-gravitating ones. However, one must reconsider the fundamental principles of statistical mechanics especially its key quantity, entropy. Whereas in conventional thermostatistics, the homogeneity and extensivity of the system and the concavity of its entropy are central conditions, these fail for the systems considered here. For example, at phase separation, the entropy, S(E), is necessarily convex to make exp[S(E)-E/T] bimodal in E. Particularly, as inhomogeneities and surface effects cannot be scaled away, one must be careful with the standard arguments of splitting a system into two subsystems, or bringing two systems into thermal contact with energy or particle exchange. Not only the volume part of the entropy must be considered. As will be shown here, when removing constraints in regions of a negative heat capacity, the system may even relax under a flow of heat (energy) against a temperature slope. Thus the Clausius formulation of the second law: ``Heat always flows from hot to cold'', can be violated. Temperature is not a necessary or fundamental control parameter of thermostatistics. However, the second law is still satisfied and the total Boltzmann entropy increases. In the final sections of this paper, the general microscopic mechanism leading to condensation and to the convexity of the microcanonical entropy at phase separation is sketched. Also the microscopic conditions for the existence (or non-existence) of a critical end-point of the phase-separation are discussed. This is explained for the liquid-gas and the solid-liquid transition.

  19. FLOW CONDITIONING DESIGN IN TURBULENT

    E-Print Network [OSTI]

    /L) · Free surface = interface between fluorescing (bright) water and (dark) air · Image obliquely with B-Injection Fusion Energy) #12;3 Motivation · Effective protection Minimize clearance between edge of liquid sheet) at FWHM · Positioning controlled by two linear stages · Water seeded with TiO2 particles (typical dia. 0

  20. Environmental Conditions Environmental Conditions

    E-Print Network [OSTI]

    Environmental Conditions Environmental Conditions Appendix II The unique geology, hydrology and instream habitat. This chapter examines how environmental conditions in the Deschutes watershed affect, the discussion characterizes the environmental conditions within three watershed areas: the Lower Deschutes

  1. Low volume flow meter

    DOE Patents [OSTI]

    Meixler, Lewis D. (East Windsor, NJ)

    1993-01-01T23:59:59.000Z

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

  2. Portable wastewater flow meter

    DOE Patents [OSTI]

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

    1990-01-01T23:59:59.000Z

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

  3. Portable wastewater flow meter

    DOE Patents [OSTI]

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

    1999-02-02T23:59:59.000Z

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

  4. Numerical simulation of the fluid flow and heat transfer processes during scavenging in a two-stroke engine under steady-state conditions

    SciTech Connect (OSTI)

    Castro Gouveia, M. de; Reis Parise, J.A. dos; Nieckele, A.O. (Pontificia Univ. Catolica, Rio de Janeiro (Brazil))

    1992-05-01T23:59:59.000Z

    A numerical simulation of the scavenging process in a two-stroke flat-piston model engine has been developed. Air enters the cylinder circumferentially, inducting a three-dimensional turbulent swirling flow. The problem was modeled as a steady-state axisymmetric flow through a cylinder with uniform wall temperature. The steady-state regime was simulated by assuming the piston head fixed at the bottom dead center. The calculation was performed employing the {kappa}-{epsilon} model of turbulence. A comparison of the results obtained for the flow field with available experimental data showed very good agreement, and a comparison with an available numerical solution revealed superior results. The effects of the Reynolds number, inlet port angles, and engine geometry on the flow and in-cylinder heat transfer characteristics were investigated. The Nusselt number substantially increases with larger Reynolds numbers and a smaller bore-to-stroke ratio. It is shown that the positioning of the exhaust value(s) is the main parameter to control the scavenging process.

  5. Combined effects of Reynolds number, turbulence intensity and periodic unsteady wake flow conditions on boundary layer development and heat transfer of a low pressure turbine blade

    E-Print Network [OSTI]

    Ozturk, Burak

    2009-05-15T23:59:59.000Z

    .18 (S R =80 mm)........................................103 Figure 11.1. Static pressure distributions at Re=110,000 and reduced frequencies S=0, 1.59, 3.18 (no rod, 160 mm, 80 mm), SS=Separation start, SE= Separation end...................................................110 Figure 11.2. Time-averaged hot-film distributions at Re=110,000 and reduced frequencies S=0, 1.59, 3.18 (no rod, 160 mm, 80 mm)...........................112 Figure 11.3. Ensemble averaged velocity as a function for (a) steady flow case S=0 (S R...

  6. Effects of alternating seawater flow and stagnant layup conditions on the general and localized corrosion resistance of CuNi and NiCu alloys in marine service

    SciTech Connect (OSTI)

    Kain, R.M. [LaQue Corrosion Services, Wrightsville Beach, NC (United States); Weber, B.E. [NAWC-Aircraft Div., Patuxent River, MD (United States)

    1997-12-01T23:59:59.000Z

    From time-to-time seawater handling systems are subjected to lay-up which can produce chemical and biological changes, and conceivably alter the corrosion resistance of metals used in piping and other equipment. In the case of reverse osmosis/membrane technology type desalination equipment, sanitizing agents may be introduced after draining. Simulation tests were conducted to determine any effect of a bisulfite sanitizing treatment when used between periods of normal seawater flow. Corresponding tests were conducted with lay-up comprising non-refreshed seawater which ultimately stagnated. Test results for CuNi alloy C71500 indicted that repeated cycling between seawater exposure and bisulfite treatments was detrimental in reducing that alloy`s resistance to general corrosion, and to a lesser degree its crevice corrosion resistance. The typical pitting and crevice corrosion behavior of NiCu alloy N04400, found upon exposure to slowly moving, aerated seawater was neither diminished or accelerated by cyclic lay-up with either stagnant seawater or the candidate bisulfite-containing solution. However, some increase in general corrosion was observed.

  7. Running Boundary Condition

    E-Print Network [OSTI]

    Satoshi Ohya; Makoto Sakamoto; Motoi Tachibana

    2013-01-28T23:59:59.000Z

    In this paper we argue that boundary condition may run with energy scale. As an illustrative example, we consider one-dimensional quantum mechanics for a spinless particle that freely propagates in the bulk yet interacts only at the origin. In this setting we find the renormalization group flow of U(2) family of boundary conditions exactly. We show that the well-known scale-independent subfamily of boundary conditions are realized as fixed points. We also discuss the duality between two distinct boundary conditions from the renormalization group point of view. Generalizations to conformal mechanics and quantum graph are also discussed.

  8. Elliptic and Hexadecapole flow of charged hadron in viscous hydrodynamics with Glauber and Color Glass Condensate initial conditions for Pb-Pb collision at $\\sqrt{s_{NN}}$=2.76 TeV

    E-Print Network [OSTI]

    Roy, Victor; Chaudhuri, A K

    2012-01-01T23:59:59.000Z

    The experimentally measured elliptic ($v_{2}$) and hexadecapole ($v_{4}$) flow of charged particles as a function of transverse momentum ($p_{T}$) at midrapidity in Pb-Pb collisions at $\\sqrt{s_{\\mathrm NN}}$ = 2.76 TeV are compared with the relativistic viscous hydrodynamic model simulations. The simulations are carried out for two different initial energy density profiles obtained from (i) Glauber model, and (ii) Color Glass Condensate (CGC) model. Comparison to experimental data for 10-20% to 40-50% centrality, shows that a centrality dependent shear viscosity to entropy density ($\\eta/s$) ratio with values ranging between 0.0 to 0.12 are needed to explain the $v_{2}$ data for simulations with the Glauber based initial condition. Whereas for the CGC based initial conditions a slightly higher value of $\\eta/s$ is preferred, around 0.08 to 0.16. From the comparison of the $v_{4}$ simulated results to the corresponding experimental measurements we observe that for the centralities 20-30% to 40-50% the $\\eta/s...

  9. MHD duct flows under hydrodynamic “slip” condition

    E-Print Network [OSTI]

    Smolentsev, S.

    2009-01-01T23:59:59.000Z

    9. Morley, N.B. , Medina, A. , Abdou, M.A. : Measurements ofSmolentsev, S. , Moreau, R. , Abdou, M. : Characterization

  10. Dryout droplet distribution and dispersed flow film boiling

    E-Print Network [OSTI]

    Hill, Wayne S.

    1982-01-01T23:59:59.000Z

    Dispersed flow film boiling is characterized by liquid-phase droplets entrained in a continuous vapor-phase flow. In a previous work at MIT, a model of dispersed flow heat transfer was developed, called the Local Conditions ...

  11. Security Conditions

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

    2004-07-08T23:59:59.000Z

    This Notice ensures that DOE uniformly meets the requirements of the Homeland Security Advisory System outlined in Homeland Security Presidential Directive-3, Threat Conditions and Associated Protective Measures, dated 3-11-02, and provides responses specified in Presidential Decision Directive 39, U.S. Policy on Counterterrorism (U), dated 6-21-95. It cancels DOE N 473.8, Security Conditions, dated 8-7-02. Extended until 7-7-06 by DOE N 251.64, dated 7-7-05 Cancels DOE N 473.8

  12. CX-010826: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Evaluation of Flow and Heat Transfer Inside Lean Pre-Mixed Combustor Systems under Reacting Flow Conditions CX(s) Applied: B3.6 Date: 07/30/2013 Location(s): Virginia Offices(s): National Energy Technology Laboratory

  13. Flow chamber

    DOE Patents [OSTI]

    Morozov, Victor (Manassas, VA)

    2011-01-18T23:59:59.000Z

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

  14. Geological flows

    E-Print Network [OSTI]

    Yu. N. Bratkov

    2008-11-19T23:59:59.000Z

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

  15. An outflow boundary condition and algorithm for incompressible two ...

    E-Print Network [OSTI]

    S. Dong

    2014-03-05T23:59:59.000Z

    Feb 22, 2014 ... [8] S. Dong, G.E. Karniadakis, C. Chryssostomidis, A robust and accurate outflow boundary condition for incompressible flow simulations on ...

  16. E-Print Network 3.0 - artificial boundary conditions Sample Search...

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

    obtained from satellite (above) and GPS mea- surements 1 as boundary conditions. The ice... by Glen's flow law: Boundary conditions are ... Source: Langhorne, Pat - Department...

  17. Comment on “Velocity boundary conditions at a tokamak resistive wall” [Phys. Plasmas 21, 032506 (2014)

    SciTech Connect (OSTI)

    Zakharov, Leonid E. [Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States); Li, Xujing [Institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing (China)

    2014-09-15T23:59:59.000Z

    The paper gives the derivation of the MHD boundary condition for the plasma flow to the wall during disruptions.

  18. Cooling Flows or Heating Flows?

    E-Print Network [OSTI]

    James Binney

    2003-10-08T23:59:59.000Z

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

  19. Nonclassical Shallow Water Flows Carina M. Edwards1

    E-Print Network [OSTI]

    Howison, Sam

    discontinuities in shallow water flows with large Froude number F. On a horizontal base, the paradigm problem is a small `tube' of fluid bounding the flow. The delta-shock conditions for this flow are derived and solved of the layer impact on a horizontal base. Keywords: delta-shock, jet impact, hypercritical flow 1 Introduction

  20. Laboratory investigations of effective flow behavior in unsaturated heterogeneous sands

    E-Print Network [OSTI]

    Wildenschild, Dorthe

    Laboratory investigations of effective flow behavior in unsaturated heterogeneous sands D, Lyngby Abstract. Two-dimensional unsaturated flow and transport through heterogeneous sand was investigated under controlled laboratory conditions. The unsaturated hydraulic conductivity of five homogeneous

  1. Interpretation of Array Production Logging Measurements in Horizontal Wells for Flow Profile

    E-Print Network [OSTI]

    Liao, Lulu

    2013-12-12T23:59:59.000Z

    and possible back flow of denser phases result in misinterpretation of the inflow distribution. To assess the downhole flow conditions more accurately, logging tools have been developed to overcome the flow regime related issues. Multiple-sensor array tools...

  2. Microstructure and Rheology of a Flow-Induced Structured Phase...

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

    salt concentration. In our work, by introducing external flow conditions via microfluidics, these micellar structures can follow very different trajectories on the phase map...

  3. Novel applications of diffusion-driven flow

    E-Print Network [OSTI]

    Allshouse, Michael R

    2010-01-01T23:59:59.000Z

    Diffusion-driven flow is the result of a conflict between hydrostatic equilibrium in a density stratified fluid and the no-flux boundary condition that must be obeyed on impermeable boundaries that are sloping with respect ...

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

    E-Print Network [OSTI]

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

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

  5. Smokeless Control of Flare Steam Flow Rate

    E-Print Network [OSTI]

    Agar, J.; Balls, B. W.

    1979-01-01T23:59:59.000Z

    the First Industrial Energy Technology Conference Houston, TX, April 22-25, 1979 FLARE GAS FLOW RATE MEASUREMENT "Accurate measurement of the very low flow rates which are normally present is very difficult" 0, p 15-8). "It is generally considered too...-04-91 Proceedings from the First Industrial Energy Technology Conference Houston, TX, April 22-25, 1979 to calibration conditions. Turndown is 40:1 and pressure loss is negligible. APPLICATION FLOW RATE The mass flow meter described has been applied to a wide...

  6. Problem Statement Characterizing the flow of neutral propellant gas

    E-Print Network [OSTI]

    Walker, Mitchell

    at the exit plane of the anode using a premixed mixture of air and propane. C3H8 + 3.76N2 + 5O2 3CO2 + 4H2O. Flow conditions (pressure, flow rate, and fuel-air ratio) that show this exit plane flow are required

  7. AXISYMMETRIC VORTEX BREAKDOWN IN AN ENCLOSED CYLINDER FLOW.

    E-Print Network [OSTI]

    Lopez, John M.

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

  8. Effective slip boundary conditions for arbitrary periodic surfaces: the surface mobility tensor

    E-Print Network [OSTI]

    Kamrin, Kenneth N.

    In a variety of applications, most notably microfluidics design, slip-based boundary conditions have been sought to characterize fluid flow over patterned surfaces. We focus on laminar shear flows over surfaces with periodic ...

  9. A survey of air flow models for multizone structures

    SciTech Connect (OSTI)

    Feustel, H.E.; Dieris, J.

    1991-03-01T23:59:59.000Z

    Air flow models are used to simulate the rates of incoming and outgoing air flows for a building with known leakage under given weather and shielding conditions. Additional information about the flow paths and air-mass flows inside the building can only by using multizone air flow models. In order to obtain more information on multizone air flow models, a literature review was performed in 1984. A second literature review and a questionnaire survey performed in 1989, revealed the existence of 50 multizone air flow models, all developed since 1966, two of which are still under development. All these programs use similar flow equations for crack flow but differ in the versatility to describe the full range of flow phenomena and the algorithm provided for solving the set of nonlinear equations. This literature review was found that newer models are able to describe and simulate the ventilation systems and interrelation of mechanical and natural ventilation. 27 refs., 2 figs., 1 tab.

  10. Coupled Generalized Nonlinear Stokes Flow with flow through a Porous Media

    E-Print Network [OSTI]

    Ervin, Vincent J.

    region and the generalized nonlinear Darcy equation in the porous medium. A flow rate is specified along boundary. In [12], the authors use the Darcy equation as a boundary condition for the Stokes problem. Abstract In this article, we analyze the flow of a fluid through a coupled Stokes-Darcy domain. The fluid

  11. Gradual Variation Analysis for Groundwater Flow

    E-Print Network [OSTI]

    Chen, Li

    2010-01-01T23:59:59.000Z

    Groundwater flow in Washington DC greatly influences the surface water quality in urban areas. The current methods of flow estimation, based on Darcy's Law and the groundwater flow equation, can be described by the diffusion equation (the transient flow) and the Laplace equation (the steady-state flow). The Laplace equation is a simplification of the diffusion equation under the condition that the aquifer has a recharging boundary. The practical way of calculation is to use numerical methods to solve these equations. The most popular system is called MODFLOW, which was developed by USGS. MODFLOW is based on the finite-difference method in rectangular Cartesian coordinates. MODFLOW can be viewed as a "quasi 3D" simulation since it only deals with the vertical average (no z-direction derivative). Flow calculations between the 2D horizontal layers use the concept of leakage. In this project, we have established a mathematical model based on gradually varied functions for groundwater data volume reconstruction. T...

  12. Original article Influence of heating conditions in continuous-flow

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , holding and cooling phases. When milk was heated in a continuous microwave heating system, at 90 °C and cooling times. vitamin B1 / vitamin B2 / milk / microwave heating Résumé -- Étude de l'effet des exchange systems on the vitamin B1 and B2 content of milk Isabel SIERRA, Concepción VIDAL

  13. ORIGINAL PAPER Conditional simulations of wateroil flow in heterogeneous porous

    E-Print Network [OSTI]

    Lu, Zhiming

    . The log-transformed intrinsic permeability, soil pore size distribution parameter, and van Genuchten of these processes in order to conduct risk assess- ment and design of cost-efficient remediation (e.g. Abriola 1989 is a complicated mixture of hydrocarbon fluids, brine, porous rock and fractures. The structure of the void space

  14. Modeling of bubbly and slug flow behavior under microgravity conditions

    E-Print Network [OSTI]

    Longeot, Matthieu Jean-Sebastien

    1995-01-01T23:59:59.000Z

    . Finally, I would like to thank my parents Jean Longeot and Nicole Sauvagnac, as well as Antoinette Repetto for their loving supports. TABLE OF CONTENTS ABSTRACT ACKNOWLEDGEMENT S. TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES NOMENCLATURE...

  15. On fluid flow in a heterogeneous medium under nonisothermal conditions

    E-Print Network [OSTI]

    D.W., Vasco

    2011-01-01T23:59:59.000Z

    aver- age of the heat capacity of the liquid and the heatthe volumetric heat capacity of the liquid, and K T = ?K l

  16. annular flow conditions: Topics by E-print Network

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

    of most ot' the experiments on the KC-135 was not to respond to a detailed study of the gas-liquid interface but to a more... attention to one configuration described as follows:...

  17. A new relation between pressure and fractional flow in two-phase flow in porous media

    E-Print Network [OSTI]

    Henning Arendt Knudsen; Alex Hansen

    2002-01-30T23:59:59.000Z

    We study average flow properties in porous media using a two-dimensional network simulator. It models the dynamics of two-phase immiscible bulk flow where film flow can be neglected. The boundary conditions are biperiodic which provide a means of studying steady state flow where complex bubble dynamics dominate the flow picture. We find fractional flow curves and corresponding pressure curves for different capillary numbers. In particular, we study the case of the two phases having equal viscosity. In this case we find that the derivative of the fractional flow with respect to saturation is related to the global pressure drop. This result can also be expressed in terms of relative permeabilities or mobilities, resulting in an equation tying together the mobilities of the two phases.

  18. Seal inlet disturbance boundary conditions for rotordynamic models and influence of some off-design conditions on labyrinth rotordynamic instability

    E-Print Network [OSTI]

    Xi, Jinxiang

    2007-04-25T23:59:59.000Z

    Systematic parametric studies were performed to better understand seal-inlet rotordynamics. A CFD-perturbation model was employed to compute the seal-inlet flow disturbance quantities. Seal inlet disturbance boundary condition correlations were...

  19. Bacteria in shear flow

    E-Print Network [OSTI]

    Marcos, Ph.D. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

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

  20. Dispersed flow film boiling

    E-Print Network [OSTI]

    Yoder, Graydon L.

    1980-01-01T23:59:59.000Z

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

  1. Microgravity Flow Regime Transition Modeling

    E-Print Network [OSTI]

    Shephard, Adam M.

    2010-07-14T23:59:59.000Z

    by Ghrist (2008) where an existing computer code, RELAP 5-3D, demonstrated the limitations of currently available computational modeling when applied to zero-g conditions. 1.2.2 EXPERIMENTAL APPARATUS All flow regime mapping experiments consist of a... ............................................................... 9 2.3 Dukler et al. 1988/Janicot 1988 ............................................. 9 2.4 Colin et al. 1991 .................................................................... 11 2.5 Huckerby and Rezkallah 1992...

  2. Radiative Flow in a Luminous Disk II

    E-Print Network [OSTI]

    Jun Fukue

    2006-01-07T23:59:59.000Z

    Radiatively-driven transfer flow perpendicular to a luminous disk is examined in the subrelativistic regime of $(v/c)^1$, taking into account the gravity of the central object. The flow is assumed to be vertical, and the gas pressure is ignored, while internal heating is assumed to be proportional to the gas density. The basic equations were numerically solved as a function of the optical depth, and the flow velocity, the height, the radiative flux, and the radiation pressure were obtained for a given radius, an initial optical depth, and initial conditions at the flow base (disk ``inside''), whereas the mass-loss rate was determined as an eigenvalue of the boundary condition at the flow top (disk ``surface''). For sufficiently luminous cases, the flow resembles the case without gravity. For less-luminous cases, however, the flow velocity decreases, and the flow would be impossible due to the existence of gravity in the case that the radiative flux is sufficiently small. Application to a supercritical accretion disk with mass loss is briefly discussed.

  3. Multiphase flow calculation software

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2003-04-15T23:59:59.000Z

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

  4. Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation Conditions)" #12;Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation Conditions, cavitation, fluid flow load, CFD. Abstract: The evaluation of fluid forces on the stem is important for wear

  5. Freshwater Flow Charts - 1995

    SciTech Connect (OSTI)

    Kaiper, G V

    2003-11-21T23:59:59.000Z

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

  6. Flow cytometer jet monitor system

    DOE Patents [OSTI]

    Van den Engh, Ger (Seattle, WA)

    1997-01-01T23:59:59.000Z

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

  7. Development of Next Generation Multiphase Pipe Flow Prediction Tools

    SciTech Connect (OSTI)

    Tulsa Fluid Flow

    2008-08-31T23:59:59.000Z

    The developments of fields in deep waters (5000 ft and more) is a common occurrence. It is inevitable that production systems will operate under multiphase flow conditions (simultaneous flow of gas-oil-and water possibly along with sand, hydrates, and waxes). Multiphase flow prediction tools are essential for every phase of the hydrocarbon recovery from design to operation. The recovery from deep-waters poses special challenges and requires accurate multiphase flow predictive tools for several applications including the design and diagnostics of the production systems, separation of phases in horizontal wells, and multiphase separation (topside, seabed or bottom-hole). It is very crucial to any multiphase separation technique that is employed either at topside, seabed or bottom-hole to know inlet conditions such as the flow rates, flow patterns, and volume fractions of gas, oil and water coming into the separation devices. The overall objective was to develop a unified model for gas-oil-water three-phase flow in wells, flow lines, and pipelines to predict the flow characteristics such as flow patterns, phase distributions, and pressure gradient encountered during petroleum production at different flow conditions (pipe diameter and inclination, fluid properties and flow rates). The project was conducted in two periods. In Period 1 (four years), gas-oil-water flow in pipes were investigated to understand the fundamental physical mechanisms describing the interaction between the gas-oil-water phases under flowing conditions, and a unified model was developed utilizing a novel modeling approach. A gas-oil-water pipe flow database including field and laboratory data was formed in Period 2 (one year). The database was utilized in model performance demonstration. Period 1 primarily consisted of the development of a unified model and software to predict the gas-oil-water flow, and experimental studies of the gas-oil-water project, including flow behavior description and closure relation development for different flow conditions. Modeling studies were performed in two parts, Technology Assessment and Model Development and Enhancement. The results of the Technology assessment study indicated that the performance of the current state of the art two-phase flow models was poor especially for three-phase pipeline flow when compared with the existing data. As part of the model development and enhancement study, a new unified model for gas-oil-water three-phase pipe flow was developed. The new model is based on the dynamics of slug flow, which shares transition boundaries with all the other flow patterns. The equations of slug flow are used not only to calculate the slug characteristics, but also to predict transitions from slug flow to other flow patterns. An experimental program including three-phase gas-oil-water horizontal flow and two-phase horizontal and inclined oil-water flow testing was conducted utilizing a Tulsa University Fluid Flow Projects Three-phase Flow Facility. The experimental results were incorporated into the unified model as they became available, and model results were used to better focus and tailor the experimental study. Finally, during the Period 2, a new three-phase databank has been developed using the data generated during this project and additional data available in the literature. The unified model to predict the gas-oil-water three phase flow characteristics was tested by comparing the prediction results with the data. The results showed good agreements.

  8. Free Flow Energy (TRL 1 2 3 Component) - Design and Development...

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

    Free Flow Energy (TRL 1 2 3 Component) - Design and Development of a Cross-Platform Submersible Generator Optimized for the Conditions of Current Energy Conversion Free Flow Energy...

  9. Variational bounds on the energy dissipation rate in body-forced shear flow

    E-Print Network [OSTI]

    Petrov, Nikola

    , the bulk (space and time averaged) dissipation rate per unit mass is proportional to the power required applied to many flows driven by boundary conditions, including shear flows and a variety of thermal

  10. Interpreting Horizontal Well Flow Profiles and Optimizing Well Performance by Downhole Temperature and Pressure Data

    E-Print Network [OSTI]

    Li, Zhuoyi

    2011-02-22T23:59:59.000Z

    be used to obtain downhole flow conditions, which is key information to control and optimize horizontal well production. However, the fluid flow in the reservoir is often multiphase and complex, which makes temperature and pressure interpretation very...

  11. Recirculation on a single stage of vertical flow constructed wetland: treatment limits and operation modes

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Recirculation on a single stage of vertical flow constructed wetland: treatment limits French vertical flow constructed wetlands (VFCWs) plant comprises two stages of treatment which the first and treatment performances in different operating conditions. Results showed good performances

  12. Columbia University flow instability experimental program: Volume 3. Single tube parallel flow tests

    SciTech Connect (OSTI)

    Dougherty, T.; Maciuca, C.; McAssey, E.V. Jr.; Reddy, D.G.; Yang, B.W.

    1990-06-01T23:59:59.000Z

    The coolant in the Savannah River Site (SRS) production nuclear reactor assemblies is circulated as a subcooled liquid under normal operating conditions. This coolant is evenly distributed throughout multiple annular flow channels with a uniform pressure profile across each coolant flow channel. During the postulated Loss of Coolant Accident (LOCA), which is initiated by a hypothetical guillotine pipe break, the coolant flow through the reactor assemblies is significantly reduced. The flow reduction and accompanying power reduction (after shutdown is initiated) occur in the first 1--2 seconds of the LOCA. This portion of the LOCA is referred to as the Flow Instability phase. A series of down flow experiments have been conducted on three different size single tubes. The objective of these experiments was to determine the effect of a parallel flow path on the occurrence of flow instability. In all cases, it has been shown that the point of flow instability (OFI) determined under controlled flow operation does not change when operating in a controlled pressure drop mode (parallel path operation).

  13. On Estimating Conditional Conservatism

    E-Print Network [OSTI]

    Ball, Ray

    The concept of conditional conservatism (asymmetric earnings timeliness) has provided new insight into financial reporting and stimulated considerable research since Basu (1997). Patatoukas and Thomas (2011) report bias ...

  14. Flow Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

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

    2000-02-22T23:59:59.000Z

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

  15. Air flow characteristics of dry and liquid loaded packed and fluidized systems

    E-Print Network [OSTI]

    Millsap, George Wayne

    1958-01-01T23:59:59.000Z

    Acknowledgnent s List of Tables List of Figures Introduction Description of s Fluidised Bed Obgectives Application 1 2 3 Description of Apparatus Test Procedure Preparation of Bed Material Beds With Upward Flow of Air Beds With Upward Flow of Air... obgectives of thi ~ investigation were: (1) to deternine the air flow-pressure drop relationships in a dry bed of unifornly sised spherical particles in both the packed and fluidised regines of air flow; (3) to deternine under the sane air flow conditions...

  16. Ultrasonic flow metering system

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

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

  17. Method for use of hydraulically or electrically controlled solenoids under failed on conditions

    DOE Patents [OSTI]

    Bolenbaugh, Jonathan M.; Naqi, Syed

    2014-07-08T23:59:59.000Z

    A method to operate a clutch device in an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and at least one electric machine includes, in response to a failure condition detected within a flow control device configured to facilitate flow of hydraulic fluid for operating the clutch device, selectively preventing the flow of hydraulic fluid from entering the flow control device and feeding the clutch device. Synchronization of the clutch device is initiated when the clutch device is intended for activation, and only if the clutch device is synchronized, the flow of hydraulic fluid is selectively permitted to enter the flow control device to activate the clutch device.

  18. Elbow mass flow meter

    DOE Patents [OSTI]

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

    1994-01-01T23:59:59.000Z

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

  19. annular two-phase flow: Topics by E-print Network

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

    performance of a gas turbine exhaust diffuser subject to the outlet flow conditions of a turbine stage is evaluated. Towards that goal, a fully three-dimensional computational...

  20. air flow maldistribution: Topics by E-print Network

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

    central air conditioning system on the basis... Liu, J.; Mai, Y.; Liu, X. 2006-01-01 77 Overheat Instability in an Ascending Moist Air Flow as a Mechanism of Hurricane Formation...

  1. air voc flow: Topics by E-print Network

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

    central air conditioning system on the basis... Liu, J.; Mai, Y.; Liu, X. 2006-01-01 97 Overheat Instability in an Ascending Moist Air Flow as a Mechanism of Hurricane Formation...

  2. “Batch” Kinetics in Flow: Online IR Analysis and Continuous Control

    E-Print Network [OSTI]

    Moore, Jason S.

    Currently, kinetic data is either collected under steady-state conditions in flow or by generating time-series data in batch. Batch experiments are generally considered to be more suitable for the generation of kinetic ...

  3. Submarine landslide flows simulation through centrifuge modelling

    E-Print Network [OSTI]

    Gue, Chang Shin

    2012-05-08T23:59:59.000Z

    ......... 140   4.6.4   Series 4: Experiments at various g le vels with a large flow rate in the dry condition ........................................................................................ 148   4.7   Repeatability of the Centrifuge Experiments... .......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .188   5.5.4   Side wall friction ..................................................................................189   5.5.5   Basal friction and pore pressure ratio ( ? ) ............................................ 194   5.6   Summary...

  4. Laminar Entrained Flow Reactor (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-02-01T23:59:59.000Z

    The Laminar Entrained Flow Reactor (LEFR) is a modular, lab scale, single-user reactor for the study of catalytic fast pyrolysis (CFP). This system can be employed to study a variety of reactor conditions for both in situ and ex situ CFP.

  5. Approximation of Axisymmetric Darcy Flow V.J. Ervin

    E-Print Network [OSTI]

    Ervin, Vincent J.

    approximation of the Darcy equations in an ax- isymmetric domain, subject to axisymmetric data. Rewriting of convergence for the RT and BDM approximations. Key words. axisymmetric flow; Darcy equation, LBB condition AMSApproximation of Axisymmetric Darcy Flow V.J. Ervin Department of Mathematical Sciences Clemson

  6. Conditional data watchpoint management

    DOE Patents [OSTI]

    Burdick, Dean Joseph (Austin, TX); Vaidyanathan, Basu (Austin, TX)

    2010-08-24T23:59:59.000Z

    A method, system and computer program product for managing a conditional data watchpoint in a set of instructions being traced is shown in accordance with illustrative embodiments. In one particular embodiment, the method comprises initializing a conditional data watchpoint and determining the watchpoint has been encountered. Upon that determination, examining a current instruction context associated with the encountered watchpoint prior to completion of the current instruction execution, further determining a first action responsive to a positive context examination; otherwise, determining a second action.

  7. Flow reversal power limit for the HFBR

    SciTech Connect (OSTI)

    Cheng, Lap Y.; Tichler, P.R.

    1995-10-01T23:59:59.000Z

    The High Flux Beam Reactor (HFBR) undergoes a buoyancy-driven reversal of flow in the reactor core following certain postulated accidents. Uncertainties about the afterheat removal capability during the flow reversal has limited the reactor operating power to 30 MW. An experimental and analytical program to address these uncertainties is described in this report. The experiments were single channel flow reversal tests under a range of conditions. The analytical phase involved simulations of the tests to benchmark the physical models and development of a criterion for dryout. The criterion is then used in simulations of reactor accidents to determine a safe operating power level. It is concluded that the limit on the HFBR operating power with respect to the issue of flow reversal is in excess of 60 MW.

  8. Spatially localized solutions of shear flows

    E-Print Network [OSTI]

    Gibson, J F

    2013-01-01T23:59:59.000Z

    We present several new spatially localized equilibrium and traveling-wave solutions of plane Couette and channel flows. The solutions exhibit strikingly concentrated regions of vorticity that are flanked on either side by high-speed streaks. For several traveling-wave solutions of channel flow, the concentrated vortex structures are confined to the near-wall region and form particularly isolated and elemental coherent structures in the near-wall region of shear flows. The solutions are constructed by a variety of methods: application of windowing functions to previously known spatially periodic solutions, continuation from plane Couette to channel flow conditions, and from initial guesses obtained from turbulent simulation data. We show how the symmetries of localized solutions derive from the symmetries of their periodic counterparts, analyze the exponential decay of their tails, examine the scale separation and scaling of their streamwise Fourier modes, and show that they develop critical layers for large R...

  9. Lateral flow strip assay

    DOE Patents [OSTI]

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

    2011-03-08T23:59:59.000Z

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

  10. CX-011013: Categorical Exclusion Determination | Department of...

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

    Exclusion Determination Distributed Fiber Optic Arrays: Integrated Temperature and Seismic Sensing for Detection of Carbon Dioxide Flow.. CX(s) Applied: A1, A9 Date: 09112013...

  11. CX-012136: Categorical Exclusion Determination | Department of...

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

    Exclusion Determination Distributed Fiber Optic Arrays: Integrated Temperature and Seismic Sensing for Detection of Carbon Dioxide Flow.. CX(s) Applied: B3.11 Date: 05272014...

  12. Development of Next Generation Multiphase Pipe Flow Prediction Tools

    SciTech Connect (OSTI)

    Cem Sarica; Holden Zhang

    2006-05-31T23:59:59.000Z

    The developments of oil and gas fields in deep waters (5000 ft and more) will become more common in the future. It is inevitable that production systems will operate under multiphase flow conditions (simultaneous flow of gas, oil and water possibly along with sand, hydrates, and waxes). Multiphase flow prediction tools are essential for every phase of hydrocarbon recovery from design to operation. Recovery from deep-waters poses special challenges and requires accurate multiphase flow predictive tools for several applications, including the design and diagnostics of the production systems, separation of phases in horizontal wells, and multiphase separation (topside, seabed or bottom-hole). It is crucial for any multiphase separation technique, either at topside, seabed or bottom-hole, to know inlet conditions such as flow rates, flow patterns, and volume fractions of gas, oil and water coming into the separation devices. Therefore, the development of a new generation of multiphase flow predictive tools is needed. The overall objective of the proposed study is to develop a unified model for gas-oil-water three-phase flow in wells, flow lines, and pipelines to predict flow characteristics such as flow patterns, phase distributions, and pressure gradient encountered during petroleum production at different flow conditions (pipe diameter and inclination, fluid properties and flow rates). In the current multiphase modeling approach, flow pattern and flow behavior (pressure gradient and phase fractions) prediction modeling are separated. Thus, different models based on different physics are employed, causing inaccuracies and discontinuities. Moreover, oil and water are treated as a pseudo single phase, ignoring the distinct characteristics of both oil and water, and often resulting in inaccurate design that leads to operational problems. In this study, a new model is being developed through a theoretical and experimental study employing a revolutionary approach. The basic continuity and momentum equations is established for each phase, and used for both flow pattern and flow behavior predictions. The required closure relationships are being developed, and will be verified with experimental results. Gas-oil-water experimental studies are currently underway for the horizontal pipes. Industry-driven consortia provide a cost-efficient vehicle for developing, transferring, and deploying new technologies into the private sector. The Tulsa University Fluid Flow Projects (TUFFP) is one of the earliest cooperative industry-university research consortia. TUFFP's mission is to conduct basic and applied multiphase flow research addressing the current and future needs of hydrocarbon production and transportation. TUFFP participants and The University of Tulsa are supporting this study through 55% cost sharing.

  13. Energy Loss Distribution in the Taylor-Couette Flow between Concentric Rotating Cylinders

    E-Print Network [OSTI]

    Dou, H S; Phan-Thien, N; Yeo, K S; Dou, Hua-Shu; Khoo, Boo Cheong; Phan-Thien, Nhan; Yeo, Khoon Seng

    2005-01-01T23:59:59.000Z

    The distribution of energy loss due to viscosity friction in plane Couette flow and Taylor-Couette Flow between concentric rotating cylinders are studied in detail for various flow conditions. The energy loss is related to the industrial processes in some fluid delivery devices and has significant influence on the flow efficiency, flow stability, turbulent transition, mixing, and heat transfer behaviours, etc. Therefore, it is very helpful to know about the energy loss distribution in the flow domain and to know its influence on the flow for understanding the flow physics. The calculation method of the energy loss distribution in the Taylor-Couette Flow between concentric rotating cylinders has not been found in open literature. In this note, the principle and the calculation are given for single cylinder rotating of inner or outer cylinder, and counter and same direction rotating of two cylinders. For comparison, the distribution of energy loss in a plane Couette flow is also derived for various flow conditi...

  14. Buoyancy-driven flow excursions in fuel assemblies

    SciTech Connect (OSTI)

    Laurinat, J.E.; Paul, P.K.; Menna, J.D.

    1995-12-31T23:59:59.000Z

    A power limit criterion was developed for a postulated Loss of Pumping Accident (LOPA) in one of the recently shut down heavy water production reactors at the Savannah River Site. These reactors were cooled by recirculating moderator downward through channels in cylindrical fuel tubes. Powers were limited to prevent a flow excursion from occurring in one or more of these parallel channels. During full-power operation, limits prevented a boiling flow excursion from taking place. At low flow rates, during the addition of emergency cooling water, buoyant forces reverse the flow in one of the coolant channels before boiling occurs. As power increases beyond the point of flow reversal, the maximum wall temperature approaches the fluid saturation temperature, and a thermal excursion occurs. The power limit criterion for low flow rates was the onset of flow reversal. To determine conditions for flow reversal, tests were performed in a mock-up of a fuel assembly that contained two electrically heated concentric tubes surrounded by three flow channels. These tests were modeled using a finite difference thermal-hydraulic code. According to code calculations, flow reversed in the outer flow channel before the maximum wall temperature reached the local fluid saturation temperature. Thermal excursions occurred when the maximum wall temperature approximately equaled the saturation temperature. For a postulated LOPA, the flow reversal criterion for emergency cooling water addition was more limiting than the boiling excursion criterion for full power operation. This criterion limited powers to 37% of historical levels.

  15. Flow dynamics and solute transport in unsaturated rock fractures

    SciTech Connect (OSTI)

    Su, G. W.

    1999-10-01T23:59:59.000Z

    Rock fractures play an important role in flow and contaminant transport in fractured aquifers, production of oil from petroleum reservoirs, and steam generation from geothermal reservoirs. In this dissertation, phenomenological aspects of flow in unsaturated fractures were studied in visualization experiments conducted on a transparent replica of a natural, rough-walled rock fracture for inlet conditions of constant pressure and flow rate over a range of angles of inclination. The experiments demonstrated that infiltrating liquid proceeds through unsaturated rock fractures along non-uniform, localized preferential flow paths. Even in the presence of constant boundary conditions, intermittent flow was a persistent flow feature observed, where portions of the flow channel underwent cycles of snapping and reforming. Two modes of intermittent flow were observed, the pulsating blob mode and the rivulet snapping mode. A conceptual model for the rivulet snapping mode was proposed and examined using idealized, variable-aperture fractures. The frequency of intermittent flow events was measured in several experiments and related to the capillary and Bond numbers to characterize this flow behavior.

  16. Cyclotron resonance in plasma flow

    SciTech Connect (OSTI)

    Artemyev, A. V.; Agapitov, O. V.; Krasnoselskikh, V. V. [LPC2E/CNRS-University of Orleans, Orleans (France)] [LPC2E/CNRS-University of Orleans, Orleans (France)

    2013-12-15T23:59:59.000Z

    This paper is devoted to the mechanism of particle acceleration via resonant interaction with the electromagnetic circular wave propagating along the inhomogeneous background magnetic field in the presence of a plasma flow. We consider the system where the plasma flow velocity is large enough to change the direction of wave propagation in the rest frame. This system mimics a magnetic field configuration typical for inner structure of a quasi-parallel shock wave. We consider conditions of gyroresonant interaction when the force corresponding to an inhomogeneity of the background magnetic field is compensated by the Lorentz force of the wave-magnetic field. The wave-amplitude is assumed to be about 10% of the background magnetic field. We show that particles can gain energy if kv{sub sw}>?>kv{sub sw}??{sub c} where k is the wave number, v{sub sw} is a plasma flow velocity, and ? and ?{sub c} are the wave frequency and the particle gyrofrequency, respectively. This mechanism of acceleration resembles the gyrosurfing mechanism, but the effect of the electrostatic field is replaced by the effect of the magnetic field inhomogeneity.

  17. Mineralogy under extreme conditions

    SciTech Connect (OSTI)

    Shu, Jinfu (CIW)

    2012-02-07T23:59:59.000Z

    We have performed measurements of minerals based on the synchrotron source for single crystal and powder X-ray diffraction, inelastic scattering, spectroscopy and radiography by using diamond anvil cells. We investigated the properties of iron (Fe), iron-magnesium oxides (Fe, Mg)O, silica(SiO{sub 2}), iron-magnesium silicates (Fe, Mg)SiO{sub 3} under simulated high pressure-high temperature extreme conditions of the Earth's crust, upper mantle, low mantle, core-mantle boundary, outer core, and inner core. The results provide a new window on the investigation of the mineral properties at Earth's conditions.

  18. Process for retarding fluid flow

    SciTech Connect (OSTI)

    Sandford, B.B.; Zillmer, R.C.

    1989-01-10T23:59:59.000Z

    A process is described for retarding the flow of fluid in a subterranean formation, comprising: (a) introducing an effective amount of a gel-forming composition into a subterranean formation, the gel-forming composition being operable when gelled in the formation for retarding the flow of fluid therein. The gel-forming composition consists of: i. a first substance dissolved in water to form an aqueous solution, the first substance being selected from the group consisting of polyvivyl alcohols, and mixtures thereof, wherein the gel-forming composition contains an amount of the first substance of from about 0.5 to about 5 weight percent of the gel-forming composition, and ii. an effective amount of glutaraldehyde which is operable for forming a weakly acidic condition having a pH from about 5.5 to less than 7 in the gel-forming composition and also operable for promoting crosslinking of the first substance and glutaraldehyde and for forming a gel from the gel-forming composition under the weakly acidic condition within a period of time no greater than about 5 days without adding an acidic catalyst to the gel-forming composition to lower the pH of the gel-forming composition below about 5.5.

  19. Flow Partitioning in Fully Saturated Soil Aggregates

    SciTech Connect (OSTI)

    Yang, Xiaofan; Richmond, Marshall C.; Scheibe, Timothy D.; Perkins, William A.; Resat, Haluk

    2014-03-30T23:59:59.000Z

    Microbes play an important role in facilitating organic matter decomposition in soils, which is a major component of the global carbon cycle. Microbial dynamics are intimately coupled to environmental transport processes, which control access to labile organic matter and other nutrients that are needed for the growth and maintenance of microorganisms. Transport of soluble nutrients in the soil system is arguably most strongly impacted by preferential flow pathways in the soil. Since the physical structure of soils can be characterized as being formed from constituent micro aggregates which contain internal porosity, one pressing question is the partitioning of the flow among the “inter-aggregate” and “intra-aggregate” pores and how this may impact overall solute transport within heterogeneous soil structures. The answer to this question is particularly important in evaluating assumptions to be used in developing upscaled simulations based on highly-resolved mechanistic models. We constructed a number of diverse multi-aggregate structures with different packing ratios by stacking micro-aggregates containing internal pores and varying the size and shape of inter-aggregate pore spacing between them. We then performed pore-scale flow simulations using computational fluid dynamics methods to determine the flow patterns in these aggregate-of-aggregates structures and computed the partitioning of the flow through intra- and inter-aggregate pores as a function of the spacing between the aggregates. The results of these numerical experiments demonstrate that soluble nutrients are largely transported via flows through inter-aggregate pores. Although this result is consistent with intuition, we have also been able to quantify the relative flow capacity of the two domains under various conditions. For example, in our simulations, the flow capacity through the aggregates (intra-aggregate flow) was less than 2% of the total flow when the spacing between the aggregates was larger than 18 micron. Inter-aggregate pores continued to be the dominant flow pathways even at much smaller spacing; intra-aggregate flow was less than 10% of the total flow when the inter- and intra-aggregate pore sizes were comparable. Such studies are making it possible to identify which model upscaling assumptions are realistic and what computational methods are required for detailed numerical investigation of microbial carbon cycling dynamics in soil systems.

  20. 2300 SYSTEM Conditioning Amplifier

    E-Print Network [OSTI]

    Gellman, Andrew J.

    2300 SYSTEM Signal Conditioning Amplifier 2310 Instruction Manual Vishay Micro-Measurements P date of shipment. Coverage of computers, cameras, rechargeable batteries, and similar items, sold on non-rechargeable batteries and similar consumable items is limited to the delivery of goods free from

  1. Turbulent flow in graphene

    E-Print Network [OSTI]

    Kumar S. Gupta; Siddhartha Sen

    2010-06-05T23:59:59.000Z

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

  2. Towards improved methods for determining porous media multiphase flow functions

    E-Print Network [OSTI]

    Xue, Song

    2004-09-30T23:59:59.000Z

    to the empirical relation by using the three-dimensional saturation and relaxation data. 7 CHAPTER II ESTIMATION OF POROUS MEDIA FLOW FUNCTIONS Multiphase flow functions are required to simulate the flow of multiple fluid phases through porous media....3) Snw + Sw = 1: (2.4) Together with boundary and initial conditions, Eqs. (2.1)-(2.4) provide a mathemat- ical model of three-dimensional, two-phase fluid flow in porous media. Several properties have to be specified in the above model. The densities...

  3. Directed and elliptic flow in Au + Au at intermediate energies

    E-Print Network [OSTI]

    Lukasik, J; Begemann-Blaich, M L; Bellaize, N; Bittiger, R; Bocage, F; Borderie, B; Bougault, R; Bouriquet, B; Charvet, J L; Chbihi, A; Dayras, R; Durand, D; Frankland, J D; Galíchet, E; Gourio, D; Guinet, D; Hudan, S; Lautesse, P; Lavaud, F; Lefčvre, A; Legrain, R; López, O; Lynen, U; Müller, W F J; Nalpas, L; Orth, H; Plagnol, E; Rosato, E; Saija, A; Schwarz, C; Sfienti, C; Tamain, B; Trautmann, W; Trzcinski, A; Turzó, K; Vient, E; Vigilante, M; Volant, C; Zwieglinski, B

    2004-01-01T23:59:59.000Z

    Directed and elliptic flow for the Au + Au system at incident energies between 40 and 150 MeV per nucleon has been measured using the INDRA 4 pi multi-detector. For semi-central collisions, the elliptic flow of Z <= 2 particles switches from in-plane to out-of-plane enhancement at around 100 MeV per nucleon, in good agreement with the result reported by the FOPI Collaboration. The directed flow changes sign at a bombarding energy between 50 and 60 MeV per nucleon and remains negative at lower energies. The conditions for the appearance and possible origins of negative flow are discussed.

  4. Stereoscopic PIV measurements of swirling flow entering a catalyst substrate

    SciTech Connect (OSTI)

    Persoons, T. [Trinity College Dublin, Mechanical Engineering Department, Parsons Building, Dublin 2 (Ireland); Vanierschot, M.; Van den Bulck, E. [Katholieke Universiteit Leuven, Department of Mechanical Engineering, Celestijnenlaan 300A, 3001 Leuven (Belgium)

    2008-09-15T23:59:59.000Z

    This experimental study investigates the stagnation region of a swirling flow entering an automotive catalyst substrate. A methodology is established using stereoscopic particle image velocimetry (PIV) to determine three-component velocity distributions up to 0.2 mm from the catalyst entrance face. In adverse conditions of strong out-of-plane velocity, PIV operating parameters are adjusted for maximum spatial correlation strength. The measurement distance to the catalyst is sufficiently small to observe radial flow spreading. A scaling analysis of the stagnation flow region provides a model for the flow uniformization as a function of the catalyst pressure drop. (author)

  5. The influence of ocean flow on newly forming sea ice Daniel L. Feltham

    E-Print Network [OSTI]

    Feltham, Daniel

    conditions. The mechanism relies on brine flows developing in the sea ice due to Bernoulli suction by flow models that parameter- ize the brine content [Maykut and Untersteiner, 1971], or treat, for example, melt. In this paper, we are interested in investigating the effect of brine flow within the sea ice, which

  6. Cerebral blood flow modeling in primate cortex Romain Guibert1,2,3,4

    E-Print Network [OSTI]

    Cerebral blood flow modeling in primate cortex Romain Guibert1,2,3,4 , Caroline Fonta3,4 and Franck report new results on blood flow modeling over large volumes of cortical gray matter of primate brain. We propose a network method for computing the blood flow, which handles realistic boundary conditions

  7. Accident Analysis and Prevention 36 (2004) 933946 Freeway safety as a function of traffic flow

    E-Print Network [OSTI]

    Detwiler, Russell

    2004-01-01T23:59:59.000Z

    Accident Analysis and Prevention 36 (2004) 933­946 Freeway safety as a function of traffic flow of strong relationships between traffic flow conditions and the likelihood of traffic accidents (crashes reserved. Keywords: Traffic safety; Accident rates; Traffic flow; Loop detectors; Speed; Traffic density

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

    E-Print Network [OSTI]

    Yotov, Ivan

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

  9. Inertially-induced secondary flow in microchannels

    E-Print Network [OSTI]

    Amini, Hamed; Di Carlo, Dino

    2011-01-01T23:59:59.000Z

    We report a novel technique to passively create strong secondary flows at moderate to high flow rates in microchannels, accurately control them and finally, due to their deterministic nature, program them into microfluidic platforms. Based on the flow conditions and due to the presence of the pillars in the channel, the flow streamlines will lose their fore-aft symmetry. As a result of this broken symmetry the fluid is pushed away from the pillar at the center of the channel (i.e. central z-plane). As the flow needs to maintain conservation of mass, the fluid will laterally travel in the opposite direction near the top and bottom walls. Therefore, a NET secondary flow will be created in the channel cross-section which is depicted in this video. The main platform is a simple straight channel with posts (i.e. cylindrical pillars - although other pillar cross-sections should also function) placed along the channel. Channel measures were 200 \\mum\\times50 \\mum, with pillars of 100 \\mum in diameter. Positioning the...

  10. ISFV14 -14th International Symposium on Flow Visualization

    E-Print Network [OSTI]

    Settles, Gary S.

    ISFV14 ­ Daegu / Korea ­ 2010 11 BACKGROUND-ORIENTED SCHLIEREN VISUALIZATION OF HEATING AND VENTILATION(s): heating, ventilation, air conditioning, flow visualization Fluid: air Visualization method(s): background airflow patterns in the heating, ventilation, and air-conditioning (HVAC) field. We propose background

  11. Air conditioning system

    DOE Patents [OSTI]

    Lowenstein, Andrew; Miller, Jeffrey; Gruendeman, Peter; DaSilva, Michael

    2005-02-01T23:59:59.000Z

    An air conditioner comprises a plurality of plates arranged in a successively stacked configuration with portions thereof having a spaced apart arrangement, and defining between successive adjacent pairs of plates at the spaced apart portions a first and second series of discrete alternating passages wherein a first air stream is passed through the first series of passages and a second air stream is passed through the second series of passages; and said stacked configuration of plates forming integrally therewith a liquid delivery means for delivering from a source a sufficient quantity of a liquid to the inside surfaces of the first series of fluid passages in a manner which provides a continuous flow of the liquid from a first end to a second end of the plurality of plates while in contact with the first air stream.

  12. High voltage pulse conditioning

    DOE Patents [OSTI]

    Springfield, Ray M. (Sante Fe, NM); Wheat, Jr., Robert M. (Los Alamos, NM)

    1990-01-01T23:59:59.000Z

    Apparatus for conditioning high voltage pulses from particle accelerators in order to shorten the rise times of the pulses. Flashover switches in the cathode stalk of the transmission line hold off conduction for a determinable period of time, reflecting the early portion of the pulses. Diodes upstream of the switches divert energy into the magnetic and electrostatic storage of the capacitance and inductance inherent to the transmission line until the switches close.

  13. Fuel gas conditioning process

    DOE Patents [OSTI]

    Lokhandwala, Kaaeid A. (Union City, CA)

    2000-01-01T23:59:59.000Z

    A process for conditioning natural gas containing C.sub.3+ hydrocarbons and/or acid gas, so that it can be used as combustion fuel to run gas-powered equipment, including compressors, in the gas field or the gas processing plant. Compared with prior art processes, the invention creates lesser quantities of low-pressure gas per unit volume of fuel gas produced. Optionally, the process can also produce an NGL product.

  14. Microelectromechanical flow control apparatus

    DOE Patents [OSTI]

    Okandan, Murat (NE Albuquerque, NM)

    2009-06-02T23:59:59.000Z

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

  15. Scaled Experimental Modeling of VHTR Plenum Flows

    SciTech Connect (OSTI)

    ICONE 15

    2007-04-01T23:59:59.000Z

    Abstract The Very High Temperature Reactor (VHTR) is the leading candidate for the Next Generation Nuclear Power (NGNP) Project in the U.S. which has the goal of demonstrating the production of emissions free electricity and hydrogen by 2015. Various scaled heated gas and water flow facilities were investigated for modeling VHTR upper and lower plenum flows during the decay heat portion of a pressurized conduction-cooldown scenario and for modeling thermal mixing and stratification (“thermal striping”) in the lower plenum during normal operation. It was concluded, based on phenomena scaling and instrumentation and other practical considerations, that a heated water flow scale model facility is preferable to a heated gas flow facility and to unheated facilities which use fluids with ranges of density to simulate the density effect of heating. For a heated water flow lower plenum model, both the Richardson numbers and Reynolds numbers may be approximately matched for conduction-cooldown natural circulation conditions. Thermal mixing during normal operation may be simulated but at lower, but still fully turbulent, Reynolds numbers than in the prototype. Natural circulation flows in the upper plenum may also be simulated in a separate heated water flow facility that uses the same plumbing as the lower plenum model. However, Reynolds number scaling distortions will occur at matching Richardson numbers due primarily to the necessity of using a reduced number of channels connected to the plenum than in the prototype (which has approximately 11,000 core channels connected to the upper plenum) in an otherwise geometrically scaled model. Experiments conducted in either or both facilities will meet the objectives of providing benchmark data for the validation of codes proposed for NGNP designs and safety studies, as well as providing a better understanding of the complex flow phenomena in the plenums.

  16. Conditions of Employment Modern Apprentice

    E-Print Network [OSTI]

    Strathclyde, University of

    Conditions of Employment Modern Apprentice 1. GENERAL CONDITIONS Members of staff are subject. Modern Apprentices are required under this agreement to undertake training, attend courses and carry out

  17. Viscous Flow Over a Chemically Patterned Surface

    E-Print Network [OSTI]

    J. E. Sprittles; Y. D. Shikhmurzaev

    2009-04-07T23:59:59.000Z

    The classical fluid dynamics boundary condition of no-slip suggests that variation in the wettability of a solid should not affect the flow of an adjacent liquid. However experiments and molecular dynamics simulations indicate that this is not the case. In this paper we show how flow over a solid substrate with variations of wettability can be described in a continuum framework using the interface formation theory developed earlier. Results demonstrate that a shear flow over a perfectly flat solid surface is disturbed by a change in its wettability, i.e. by a change in the chemistry of the solid substrate. The magnitude of the effect is shown to be proportional to cos(t1)-cos(t2) where t1 and t2 are the equilibrium contact angles that a liquid-gas free surface would form with the two chemically different parts of the solid surface.

  18. Influence of shear viscosity on the correlation between the triangular flow and initial spatial triangularity

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2011-12-06T23:59:59.000Z

    In a hydrodynamic model, with fluctuating initial conditions, the correlation between triangular flow and initial spatial triangularity is studied. The triangular flow, even in ideal fluid, is only weakly correlated with the initial triangularity. The correlation is largely reduced in viscous fluid. Elliptic flow on the other hand appears to be strongly correlated with initial eccentricity. Weak correlation between triangular flow and initial triangularity indicate that a part of triangular flow is unrelated to initial triangularity. Triangularity acquired during the fluid evolution also contributes to the triangular flow.

  19. Influence of shear viscosity on the correlation between the triangular flow and initial spatial triangularity

    E-Print Network [OSTI]

    Chaudhuri, A K

    2011-01-01T23:59:59.000Z

    In a hydrodynamic model, with fluctuating initial conditions, the correlation between triangular flow and initial spatial triangularity is studied. The triangular flow, even in ideal fluid, is only weakly correlated with the initial triangularity. The correlation is largely reduced in viscous fluid. Elliptic flow on the other hand appears to be strongly correlated with initial eccentricity. Weak correlation between triangular flow and initial triangularity indicate that a part of triangular flow is unrelated to initial triangularity. Triangularity acquired during the fluid evolution also contributes to the triangular flow.

  20. Magnetically stimulated fluid flow patterns

    ScienceCinema (OSTI)

    Martin, Jim; Solis, Kyle

    2014-08-06T23:59:59.000Z

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

  1. Magnetically stimulated fluid flow patterns

    SciTech Connect (OSTI)

    Martin, Jim; Solis, Kyle

    2014-03-06T23:59:59.000Z

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

  2. Stability analysis of natural circulation in BWRs at high pressure conditions

    E-Print Network [OSTI]

    Hu, Rui, Ph. D. Massachusetts Institute of Technology

    2007-01-01T23:59:59.000Z

    At rated conditions, a natural circulation boiling water reactor (NCBWR) depends completely on buoyancy to remove heat from the reactor core. This raises the issue of potential unstable flow. oscillations. The objective ...

  3. Flow of suspensions in pipelines

    SciTech Connect (OSTI)

    Nasr-El-Din, H.A. [Laboratory R& D Center, Saudi Aramco, Dhahran (Saudi Arabia)

    1996-12-31T23:59:59.000Z

    Slurry pipelines are used in many industrial applications. Several parameters are often needed by the operator, including critical deposit velocity, solids concentration, and particle velocity profiles. This chapter first reviews important formulas used to predict critical deposit velocity both in Newtonian and non-Newtonian (power-law) carrier fluids. Various methods to measure local velocity and solids concentration profiles in slurry pipelines are discussed. Local solids concentration can be measured by sample withdrawal technique. However, the sample should be withdrawn at isokinetic conditions. Sampling downstream of tees and elbows can result in significant errors in measuring solids concentration. Gamma-ray absorption methods can be used; however, two scans are needed to obtain local solids concentration. Bulk velocity of conductive slurries can be obtained using magnetic flow meters mounted on a vertical section of the pipe. Local particle velocity can be obtained using conductivity probes. NMR methods can be used to measure concentration and particle velocity profiles but are limited to small-diameter pipes. Vertical solids concentration of coarse slurries flowing in a horizontal pipeline exhibits a positive gradient near the bottom of the pipe. Traditional models to predict these profiles are given, and new mathematical models and computer software to determine these profiles are introduced. 104 refs., 31 figs., 1 tab.

  4. Conditional sterility in plants

    DOE Patents [OSTI]

    Meagher, Richard B. (Athens, GA); McKinney, Elizabeth (Athens, GA); Kim, Tehryung (Taejeon, KR)

    2010-02-23T23:59:59.000Z

    The present disclosure provides methods, recombinant DNA molecules, recombinant host cells containing the DNA molecules, and transgenic plant cells, plant tissue and plants which contain and express at least one antisense or interference RNA specific for a thiamine biosynthetic coding sequence or a thiamine binding protein or a thiamine-degrading protein, wherein the RNA or thiamine binding protein is expressed under the regulatory control of a transcription regulatory sequence which directs expression in male and/or female reproductive tissue. These transgenic plants are conditionally sterile; i.e., they are fertile only in the presence of exogenous thiamine. Such plants are especially appropriate for use in the seed industry or in the environment, for example, for use in revegetation of contaminated soils or phytoremediation, especially when those transgenic plants also contain and express one or more chimeric genes which confer resistance to contaminants.

  5. Initial Cladding Condition

    SciTech Connect (OSTI)

    E. Siegmann

    2000-08-22T23:59:59.000Z

    The purpose of this analysis is to describe the condition of commercial Zircaloy clad fuel as it is received at the Yucca Mountain Project (YMP) site. Most commercial nuclear fuel is encased in Zircaloy cladding. This analysis is developed to describe cladding degradation from the expected failure modes. This includes reactor operation impacts including incipient failures, potential degradation after reactor operation during spent fuel storage in pool and dry storage and impacts due to transportation. Degradation modes include cladding creep, and delayed hydride cracking during dry storage and transportation. Mechanical stresses from fuel handling and transportation vibrations are also included. This Analysis and Model Report (AMR) does not address any potential damage to assemblies that might occur at the YMP surface facilities. Ranges and uncertainties have been defined. This analysis will be the initial boundary condition for the analysis of cladding degradation inside the repository. In accordance with AP-2.13Q, ''Technical Product Development Planning'', a work plan (CRWMS M&O 2000c) was developed, issued, and utilized in the preparation of this document. There are constraints, caveats and limitations to this analysis. This cladding degradation analysis is based on commercial Pressurized Water Reactor (PWR) fuel with Zircaloy cladding but is applicable to Boiling Water Reactor (BWR) fuel. Reactor operating experience for both PWRs and BWRs is used to establish fuel reliability from reactor operation. It is limited to fuel exposed to normal operation and anticipated operational occurrences (i.e. events which are anticipated to occur within a reactor lifetime), and not to fuel that has been exposed to severe accidents. Fuel burnup projections have been limited to the current commercial reactor licensing environment with restrictions on fuel enrichment, oxide coating thickness and rod plenum pressures. The information provided in this analysis will be used in evaluating the post-closure performance of the Monitored Geologic Repository (MGR) in relation to waste form degradation.

  6. Parallel flow diffusion battery

    DOE Patents [OSTI]

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

    1984-01-01T23:59:59.000Z

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

  7. Optical flow switching

    E-Print Network [OSTI]

    Chan, Vincent W. S.

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

  8. Olefin Autoxidation in Flow

    E-Print Network [OSTI]

    Neuenschwander, Ulrich

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

  9. CX-001417: Categorical Exclusion Determination | Department of...

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

    Exclusion Determination Field Verification of High-Penetration Levels of Photovoltaic into the Distribution Grid with Advanced Power Conditioning Systems CX(s) Applied:...

  10. CX-003856: Categorical Exclusion Determination | Department of...

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

    Determination CX-003856: Categorical Exclusion Determination Road Prison Geothermal Earth Coupled Heating, Ventilation and Air Conditioning (HVAC) Upgrade CX(s) Applied: B5.1...

  11. CX-002034: Categorical Exclusion Determination | Department of...

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

    Determination CX-002034: Categorical Exclusion Determination Road Prison Geothermal Earth Coupled Heating, Ventilation, and Air Conditioning Upgrade CX(s) Applied: B3.1, A9...

  12. Conjugate flow action functionals

    SciTech Connect (OSTI)

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

    2013-11-15T23:59:59.000Z

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

  13. A Guide for Using the Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California

    SciTech Connect (OSTI)

    Joan B. Blainey; Claudia C. Faunt, and Mary C. Hill

    2006-05-16T23:59:59.000Z

    This report is a guide for executing numerical simulations with the transient ground-water flow model of the Death Valley regional ground-water flow system, Nevada and California using the U.S. Geological Survey modular finite-difference ground-water flow model, MODFLOW-2000. Model inputs, including observations of hydraulic head, discharge, and boundary flows, are summarized. Modification of the DVRFS transient ground-water model is discussed for two common uses of the Death Valley regional ground-water flow system model: predictive pumping scenarios that extend beyond the end of the model simulation period (1998), and model simulations with only steady-state conditions.

  14. Section 13: Flow control 1 Section 13: Flow control

    E-Print Network [OSTI]

    Kohlenbach, Ulrich

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

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

    E-Print Network [OSTI]

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

  16. Semiclassical energy conditions and wormholes

    E-Print Network [OSTI]

    Prado Martin-Moruno

    2014-11-17T23:59:59.000Z

    We consider the nonlinear energy conditions and their quantum extensions. These new energy conditions behave much better than the usual pointwise energy conditions in the presence of semiclassical quantum effects. Analogous quantum extensions for the linear energy conditions are not always satisfied as one enters the quantum realm, but they can be used to constrain the violation of the classical conditions. Thus, the existence of wormholes supported by a fluid which violates the null energy condition in a controlled way is of particular interest.

  17. Flow instability and critical heat flux in a ribbed annulus

    SciTech Connect (OSTI)

    Yang, B.W.; Dougherty, T.; Fighetti, C.; Kokolis, S.; Reddy, G.D. [Columbia Univ., New York, NY (United States); McAssey, E.V. Jr. [Villanova Univ., PA (United States); Coutts, A. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1993-11-01T23:59:59.000Z

    An experimental program has been conducted to determine the onset of flow instability point in a heated annulus which is divided into four sub channels by non-conducting ribs. The onset of flow instability is identified by the minimum point in the pressure drop-velocity curve. Comparison with a ribless annulus show that the presence of ribs increases the minimum point velocity. In addition, data are presented which show that under certain conditions premature CHF can be induced by the ribs.

  18. SATURATED-SUBCOOLED STRATIFIED FLOW IN HORIZONTAL PIPES

    SciTech Connect (OSTI)

    Richard Schultz

    2010-08-01T23:59:59.000Z

    Advanced light water reactor systems are designed to use passive emergency core cooling systems with horizontal pipes that provide highly subcooled water from water storage tanks or passive heat exchangers to the reactor vessel core under accident conditions. Because passive systems are driven by density gradients, the horizontal pipes often do not flow full and thus have a free surface that is exposed to saturated steam and stratified flow is present.

  19. Fission product release from irradiated LWR fuel under accident conditions

    SciTech Connect (OSTI)

    Strain, R.V.; Sanecki, J.E.; Osborne, M.F.

    1984-01-01T23:59:59.000Z

    Fission product release from irradiated LWR fuel is being studied by heating fuel rod segments in flowing steam and an inert carrier gas to simulate accident conditions. Fuels with a range of irradiation histories are being subjected to several steam flow rates over a wide range of temperatures. Fission product release during each test is measured by gamma spectroscopy and by detailed examination of the collection apparatus after the test has been completed. These release results are complemented by a detailed posttest examination of samples of the fuel rod segment. Results of release measurements and fuel rod characterizations for tests at 1400 through 2000/sup 0/C are presented in this paper.

  20. Friction and the oscillatory motion of granular flows

    E-Print Network [OSTI]

    Lydie Staron

    2012-11-26T23:59:59.000Z

    This contribution reports on numerical simulations of 2D granular flows on erodible beds. The broad aim is to investigate whether simple flows of model granular matter exhibits spontaneous oscillatory motion in generic flow conditions, and in this case, whether the frictional properties of the contacts between grains may affect the existence or the characteristics of this oscillatory motion. The analysis of different series of simulations show that the flow develops an oscillatory motion with a well-defined frequency which increases like the inverse of the velocity's square root. We show that the oscillation is essentially a surface phenomena. The amplitude of the oscillation is higher for lower volume fractions, and can thus be related to the flow velocity and grains friction properties. The study of the influence of the periodic geometry of the simulation cell shows no significant effect. These results are discussed in relation to sonic sands.

  1. Interplay between geometry and flow distribution in an airway tree

    E-Print Network [OSTI]

    Mauroy, B; Sapoval, B

    2003-01-01T23:59:59.000Z

    Uniform fluid flow distribution in a symmetric volume can be realized through a symmetric branched tree. It is shown here, however, that the flow partitioning can be highly sensitive to deviations from exact symmetry if inertial effects are present. This is found by direct numerical simulation of the Navier-Stokes equations in a 3D tree geometry. The flow asymmetry is quantified and found to depend on the Reynolds number. Moreover, for a given Reynolds number, we show that the flow distribution depends on the aspect ratio of the branching elements as well as their angular arrangement. Our results indicate that physiological variability should be severely restricted in order to ensure uniform fluid distribution in a tree. This study suggests that any non-uniformity in the air flow distribution in human lungs should be influenced by the respiratory conditions, rest or hard exercise.

  2. Flow of Navier-Stokes Fluids in Cylindrical Elastic Tubes

    E-Print Network [OSTI]

    Sochi, Taha

    2013-01-01T23:59:59.000Z

    Analytical expressions correlating the volumetric flow rate to the inlet and outlet pressures are derived for the time-independent flow of Newtonian fluids in cylindrically-shaped elastic tubes using a one-dimensional Navier-Stokes flow model with two pressure-area constitutive relations. These expressions for elastic tubes are the equivalent of Poiseuille and Poiseuille-type expressions for rigid tubes which were previously derived for the flow of Newtonian and non-Newtonian fluids under various flow conditions. Formulae and procedures for identifying the pressure field and tube geometric profile are also presented. The results are validated by a finite element method implementation. Sensible trends in the analytical and numerical results are observed and documented.

  3. Piezoelectric axial flow microvalve

    SciTech Connect (OSTI)

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

    2007-01-09T23:59:59.000Z

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

  4. Condition Monitoring System for Reinforced

    E-Print Network [OSTI]

    Painter, Kevin

    containing dissolved ionic species such as chlorides. Since concrete is a porous material, with timeCondition Monitoring System for Reinforced Concrete Structures PROBLEM THIS TECHNOLOGY SOLVES: Patent pending concrete condition monitoring system providing `real-time' information on temperature

  5. A study of vapor-liquid flow in porous media

    SciTech Connect (OSTI)

    Satik, Cengiz; Yortsos, Yanis C.

    1994-01-20T23:59:59.000Z

    We study the heat transfer-driven liquid-to-vapor phase change in single-component systems in porous media by using pore network models and flow visualization experiments. Experiments using glass micromodels were conducted. The flow visualization allowed us to define the rules for the numerical pore network model. A numerical pore network model is developed for vapor-liquid displacement where fluid flow, heat transfer and capillarity are included at the pore level. We examine the growth process at two different boundary conditions.

  6. When Does Aid Conditionality Work?

    E-Print Network [OSTI]

    Montinola, Gabriella R.

    2010-01-01T23:59:59.000Z

    2005, the Group of Eight (G8) nations committed to increaseprogram conditions. Given the G8 industrialized nations’

  7. Twilight for the energy conditions?

    E-Print Network [OSTI]

    Visser, Matt

    Twilight for the energy conditions? Matt Visser Physics Department Washington University Saint;#16;s (CAB, Madrid) Marcel Grossmann 9 Roma July 2000 #12; Abstract: The energy conditions of general relativity per- mit one to deduce very powerful and general theorems. However, the energy conditions are now

  8. TTProblem A Air Conditioning Machinery

    E-Print Network [OSTI]

    California at Berkeley, University of

    TTProblem A Air Conditioning Machinery Input file: ducts.in You are a technician for the Air Conditioning Machinery company (ACM). Unfortunately, when you arrive at a customer site to install some air conditioning ducts, you discover that you are running low on supplies. You have only six duct segments

  9. Energy conditions and their implications

    E-Print Network [OSTI]

    Visser, Matt

    Energy conditions and their implications Matt Visser Physics Department Washington University Saint;#16;s (Los Alamos) Midwest Relativity 9 November 1999. #12; Abstract: The energy conditions of general- itational #12;elds and cosmological geometries. However, the energy conditions are beginning to look a lot

  10. Gaseous Flows in Galaxies

    E-Print Network [OSTI]

    F. Combes

    2007-09-02T23:59:59.000Z

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

  11. On integrating LES and laboratory turbulent flow experiments

    SciTech Connect (OSTI)

    Grinstein, Fernando Franklin [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    Critical issues involved in large eddy simulation (LES) experiments relate to the treatment of unresolved subgrid scale flow features and required initial and boundary condition supergrid scale modelling. The inherently intrusive nature of both LES and laboratory experiments is noted in this context. Flow characterization issues becomes very challenging ones in validation and computational laboratory studies, where potential sources of discrepancies between predictions and measurements need to be clearly evaluated and controlled. A special focus of the discussion is devoted to turbulent initial condition issues.

  12. Genealogy of flows of continuous-state branching processes via flows of partitions and the Eve property

    E-Print Network [OSTI]

    Labbé, Cyril

    2012-01-01T23:59:59.000Z

    We encode the genealogy of a continuous-state branching process associated with a branching mechanism $\\Psi$ - or $\\Psi$-CSBP in short - using a stochastic flow of partitions. This encoding holds for all branching mechanisms and appears as a very tractable object to deal with asymptotic behaviours and convergences. In particular we study the so-called Eve property - the existence of an ancestor from which the entire population descends asymptotically - and give a necessary and sufficient condition on the $\\Psi$-CSBP for this property to hold. Finally, we show that the flow of partitions unifies the lookdown representation and the flow of subordinators when the Eve property holds.

  13. Multiphase cooling flows

    E-Print Network [OSTI]

    Peter A. Thomas

    1996-08-20T23:59:59.000Z

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

  14. Matter Under Extreme Conditions: The Early Years

    E-Print Network [OSTI]

    Keeler, R Norris

    2010-01-01T23:59:59.000Z

    Extreme conditions in natural flows are examined, starting with a turbulent big bang. A hydro-gravitational-dynamics cosmology model is adopted. Planck-Kerr turbulence instability causes Planck-particle turbulent combustion. Inertial-vortex forces induce a non-turbulent kinetic energy cascade to Planck-Kolmogorov scales where vorticity is produced, overcoming 10^113 Pa Planck-Fortov pressures. The spinning, expanding fireball has a slight deficit of Planck antiparticles. Space and mass-energy powered by gluon viscous stresses expand exponentially at speeds >10^25 c. Turbulent temperature and spin fluctuations fossilize at scales larger than ct, where c is light speed and t is time. Because â??dark-energyâ?ť antigravity forces vanish when inflation ceases, and because turbulence produces entropy, the universe is closed and will collapse and rebound. Density and spin fossils of big bang turbulent mixing trigger structure formation in the plasma epoch. Fragmenting protosuperclustervoids and protoclustervoi...

  15. Journal of the Korean Physical Society, Vol. 51, No. 3, September 2007, pp. 11131118 Characteristics of Thermal-Flow Fields in a PECVD Reactor

    E-Print Network [OSTI]

    Boo, Jin-Hyo

    Characteristics of Thermal-Flow Fields in a PECVD Reactor with Various Operating Conditions Jae-Sang Baek and Youn be influenced by the reactor geometry, the thermo-flow conditions, and the operation procedure. In this study, the effects of various operating conditions and the shapes of the PECVD reactor are considered to elucidate

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

    SciTech Connect (OSTI)

    Not Available

    1986-01-27T23:59:59.000Z

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

  17. Flow reversal power limit for the HFBR

    SciTech Connect (OSTI)

    Cheng, L.Y.; Tichler, P.R.

    1997-01-01T23:59:59.000Z

    The High Flux Beam Reactor (HFBR) is a pressurized heavy water moderated and cooled research reactor that began operation at 40 MW. The reactor was subsequently upgraded to 60 MW and operated at that level for several years. The reactor undergoes a buoyancy-driven reversal of flow in the reactor core following certain postulated accidents. Questions which were raised about the afterheat removal capability during the flow reversal transition led to a reactor shutdown and subsequent resumption of operation at a reduced power of 30 MW. An experimental and analytical program to address these questions is described in this report. The experiments were single channel flow reversal tests under a range of conditions. The analytical phase involved simulations of the tests to benchmark the physical models and development of a criterion for dryout. The criterion is then used in simulations of reactor accidents to determine a safe operating power level. It is concluded that the limit on the HFBR operating power with respect to the issue of flow reversal is in excess of 60 MW. Direct use of the experimental results and an understanding of the governing phenomenology supports this conclusion.

  18. Gas-surface interaction and boundary conditions for the Boltzmann equation

    E-Print Network [OSTI]

    Mieussens, Luc

    Gas-surface interaction and boundary conditions for the Boltzmann equation St´ephane Brull, Pierre Equation. The interaction between the wall atoms and the gas molecules within a thin surface layer of the gas in the bulk flow. Boundary conditions are formally derived from this model by using classical

  19. Variation of hydraulic conductance of some adult conifers under natural conditions

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Variation of hydraulic conductance of some adult conifers under natural conditions A. Granier, N; in the liquid phase, the flow depends upon water potential gradients and hydraulic conductance from the soil present here some evaluations of hydraulic conductance of trees growing under natural conditions. Data

  20. Flow cytometry apparatus

    DOE Patents [OSTI]

    Pinkel, Daniel (Walnut Creek, CA)

    1991-01-01T23:59:59.000Z

    An obstruction across the flow chamber creates a one dimensional convergence of a sheath fluid. A passageway in the construction directs flat cells near to the area of one dimensional convergence in the sheath fluid to provide proper orientation of flat cells at fast rates.

  1. AGN and Cooling Flows

    E-Print Network [OSTI]

    James Binney

    2001-03-23T23:59:59.000Z

    For two decades the steady-state cooling-flow model has dominated the literature of cluster and elliptical-galaxy X-ray sources. For ten years this model has been in severe difficulty from a theoretical point of view, and it is now coming under increasing pressure observationally. For two decades the steady-state cooling-flow model has dominated the literature of cluster and elliptical-galaxy X-ray sources. For ten years this model has been in severe difficulty from a theoretical point of view, and it is now coming under increasing pressure observationally. A small number of enthusiasts have argued for a radically different interpretation of the data, but had little impact on prevailing opinion because the unsteady heating picture that they advocate is extremely hard to work out in detail. Here I explain why it is difficult to extract robust observational predictions from the heating picture. Major problems include the variability of the sources, the different ways in which a bi-polar flow can impact on X-ray emission, the weakness of synchrotron emission from sub-relativistic flows, and the sensitivity of synchrotron emission to a magnetic field that is probably highly localized.

  2. Data-flow graphs as a model of parallel complexity

    SciTech Connect (OSTI)

    Campbell, M.L.

    1987-01-01T23:59:59.000Z

    A new model of parallel computation based on data-flow graphs is introduced, which is specifically oriented towards complexity theory. Data-flow graphs are capable of illustrating properties of synchronous, asynchronous, and nondeterministic computations. Sufficient conditions are derived for asynchronous data-flow graphs to be determinate, i.e., all possible computations are finite and yield the same result. For determinate graphs, it is shown that the synchronous computation is as fast as any asynchronous computation. An algorithm is presented that transforms a nondeterminate data-flow graphs into a synchronous determinate one. The basic data-flow graph idea is extended into a model with greater potential parallelism, called the Uniform Data Flow Graph Family (UDFGF) Model. It is proved that time and space for the UDFGF model are polynomially related to reversal and space for the Turing Machine model, in both the deterministic and nondeterministic cases. In addition to forming an abstract computational model, data-flow graphs are parallel programs for real multiprocessors. Given a data flow graph program and a multiprocessor, each node of the graph must be assigned to one of the processors. It is proved that this problem is intractable, and a practical algorithm to find approximate solutions for it is presented.

  3. Flow and evaporation in single micrometer and nanometer scale pipes

    SciTech Connect (OSTI)

    Velasco, A. E.; Yang, C.; Siwy, Z. S.; Taborek, P. [Department of Physics and Astronomy, University of California, Irvine 92697 (United States); Toimil-Molares, M. E. [Department of Materials Science, GSI Helmholtzzentrum fur Schwerionenforschung GmbH, Darmstadt (Germany)

    2014-07-21T23:59:59.000Z

    We report measurements of pressure driven flow of fluids entering vacuum through a single pipe of micrometer or nanometer scale diameter. Nanopores were fabricated by etching a single ion track in polymer or mica foils. A calibrated mass spectrometer was used to measure the flow rates of nitrogen and helium through pipes with diameter ranging from 10??m to 31?nm. The flow of gaseous and liquid nitrogen was studied near 77?K, while the flow of helium was studied from the lambda point (2.18?K) to above the critical point (5.2?K). Flow rates were controlled by changing the pressure drop across the pipe in the range 0–31 atm. When the pressure in the pipe reached the saturated vapor pressure, an abrupt flow transition was observed. A simple viscous flow model is used to determine the position of the liquid/vapor interface in the pipe. The observed mass flow rates are consistent with no slip boundary conditions.

  4. An improved model for flashing flow in short tubes

    SciTech Connect (OSTI)

    Tilton, J.D.; Kornhauser, A.A. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Dept. of Mechanical Engineering

    1996-12-31T23:59:59.000Z

    Short tube restrictors are commonly used as expansion devices in refrigeration and heat pumping systems. Flashing flow through short tubes is choked, i.e. independent of downstream conditions. Flow rate is typically predicted by empirically correcting the flow rate of compressed liquid from upstream pressure to saturation pressure at upstream temperature. The empirical correction factors depend on pressure and temperature, on short tube geometry, and on the refrigerant used. This work extends and improves a model of short tube flow based on the physics of the observed flow phenomena. Short tube flow is believed to consist of a core of superheated liquid surrounded by an annulus of vapor. Evaporation is driven by heat transfer form the core to tine interface, and the flow is choked by the evaporated vapor. Flow rate is modeled by calculating the heat transfer rate, the evaporation rate, and the choking effect of the vapor. The model attempts to improve on previous work by improving the accuracy with which thermodynamic properties are approximated, by improving the heat transfer model, and by including the effects of frictional heating of the liquid. In comparisons with experimental data it is found that the improved thermodynamic modeling increases accuracy, but the change to the heat transfer model reduces accuracy. For the data examined the effects of the frictional heating are small. The heat transfer model is based on an existing analytic solution with a mixing-length turbulence model. It appears that this model must be further improved, perhaps through empirical modification.

  5. A void distribution model-flashing flow

    SciTech Connect (OSTI)

    Riznic, J.; Ishii, M.; Afgan, N.

    1987-01-01T23:59:59.000Z

    A new model for flashing flow based on wall nucleations is proposed here and the model predictions are compared with some experimental data. In order to calculate the bubble number density, the bubble number transport equation with a distributed source from the wall nucleation sites was used. Thus it was possible to avoid the usual assumption of a constant bubble number density. Comparisons of the model with the data shows that the model based on the nucleation site density correlation appears to be acceptable to describe the vapor generation in the flashing flow. For the limited data examined, the comparisons show rather satisfactory agreement without using a floating parameter to adjust the model. This result indicated that, at least for the experimental conditions considered here, the mechanistic predictions of the flashing phenomenon is possible on the present wall nucleation based model.

  6. Brine flow in heated geologic salt.

    SciTech Connect (OSTI)

    Kuhlman, Kristopher L.; Malama, Bwalya

    2013-03-01T23:59:59.000Z

    This report is a summary of the physical processes, primary governing equations, solution approaches, and historic testing related to brine migration in geologic salt. Although most information presented in this report is not new, we synthesize a large amount of material scattered across dozens of laboratory reports, journal papers, conference proceedings, and textbooks. We present a mathematical description of the governing brine flow mechanisms in geologic salt. We outline the general coupled thermal, multi-phase hydrologic, and mechanical processes. We derive these processes' governing equations, which can be used to predict brine flow. These equations are valid under a wide variety of conditions applicable to radioactive waste disposal in rooms and boreholes excavated into geologic salt.

  7. Particle acceleration efficiencies in astrophysical shear flows

    E-Print Network [OSTI]

    F. M. Rieger; P. Duffy

    2005-02-04T23:59:59.000Z

    The acceleration of energetic particles in astrophysical shear flows is analyzed. We show that in the presence of a non-relativistic gradual velocity shear, power law particle momentum distributions $f(p) \\propto p^{-(3+\\alpha)}$ may be generated, assuming a momentum-dependent scattering time $\\tau \\propto p^{\\alpha}$, with $\\alpha > 0$. We consider possible acceleration sites in astrophysical jets and study the conditions for efficient acceleration. It is shown, for example, that in the presence of a gradual shear flow and a gyro-dependent particle mean free path, synchrotron radiation losses no longer stop the acceleration once it has started to work efficiently. This suggests that shear acceleration may naturally account for a second, non-thermal population of energetic particles in addition to a shock-accelerated one. The possible relevance of shear acceleration is briefly discussed with reference to the relativistic jet in the quasar 3C 273.

  8. Coupling free flow / porous-medium flow General idea

    E-Print Network [OSTI]

    Cirpka, Olaf Arie

    equation t (v) + div (vv ) - div(v) + p - g - qv = 0 Darcy flow equation t (S) - div K (p - g) - qpmT transport equation t (X) + div (vX - DsteamX) = qsteam 16/14 #12;Backup additional Darcy flow equations-Stokes 1 phase, 2 components, temperature sharp interface porous-medium / Darcy flow 2 phases, 2 component

  9. Belief Revision through Forgetting Conditionals in Conditional Probabilistic Logic Programs

    E-Print Network [OSTI]

    Liu, Weiru

    of probabilistic belief revising, most research focuses on revising a single probabilistic distribution [5, 1, 8, 4Belief Revision through Forgetting Conditionals in Conditional Probabilistic Logic Programs Anbu Yue 1 and Weiru Liu 1 Abstract. In this paper, we present a revision strategy of revis- ing

  10. Conditional entropy of ordinal patterns

    E-Print Network [OSTI]

    Anton M. Unakafov; Karsten Keller

    2014-07-21T23:59:59.000Z

    In this paper we investigate a quantity called conditional entropy of ordinal patterns, akin to the permutation entropy. The conditional entropy of ordinal patterns describes the average diversity of the ordinal patterns succeeding a given ordinal pattern. We observe that this quantity provides a good estimation of the Kolmogorov-Sinai entropy in many cases. In particular, the conditional entropy of ordinal patterns of a finite order coincides with the Kolmogorov-Sinai entropy for periodic dynamics and for Markov shifts over a binary alphabet. Finally, the conditional entropy of ordinal patterns is computationally simple and thus can be well applied to real-world data.

  11. Message Flow Modulator Final Report

    E-Print Network [OSTI]

    Boyer, Robert Stephen

    operational environment at the Patuxent River Naval Air Test Center with scenarios developed by an independent in testing and demonstrating the flow modulator at the Patuxent River Naval Air Test Center. #12;MESSAGE FLOW

  12. Radial flow pulse jet mixer

    DOE Patents [OSTI]

    VanOsdol, John G.

    2013-06-25T23:59:59.000Z

    The disclosure provides a pulse jet mixing vessel for mixing a plurality of solid particles. The pulse jet mixing vessel is comprised of a sludge basin, a flow surface surrounding the sludge basin, and a downcoming flow annulus between the flow surface and an inner shroud. The pulse jet mixing vessel is additionally comprised of an upper vessel pressurization volume in fluid communication with the downcoming flow annulus, and an inner shroud surge volume separated from the downcoming flow annulus by the inner shroud. When the solid particles are resting on the sludge basin and a fluid such as water is atop the particles and extending into the downcoming flow annulus and the inner shroud surge volume, mixing occurs by pressurization of the upper vessel pressurization volume, generating an inward radial flow over the flow surface and an upwash jet at the center of the sludge basin.

  13. Flow (2008) Director: Irena Salina

    E-Print Network [OSTI]

    Hemmers, Oliver

    2008-01-01T23:59:59.000Z

    Flow (2008) Director: Irena Salina Run Time: 93 min. Summary: ,Irena Salina's documentary film://documentaryfilms.suite101.com/article.cfm/desperate_for_water_irena_salinas_movie_flow No Dumb Questions (2001) Director

  14. Ricci flow and quantum theory

    E-Print Network [OSTI]

    Robert Carroll

    2007-11-05T23:59:59.000Z

    We show some relations between Ricci flow and quantum theory via Fisher information and the quantum potential.

  15. Progress in Grid Scale Flow Batteries

    E-Print Network [OSTI]

    2011Year #12;Flow Battery Research at PNNL and Sandia #12 with industries and universities New Generation Redox Flow Batteries, PNNL Developed new generation redox flow

  16. A Holistic Framework for Environmental Flows Determination in Hydropower Contexts

    SciTech Connect (OSTI)

    McManamay, Ryan A [ORNL; Bevelhimer, Mark S [ORNL

    2013-05-01T23:59:59.000Z

    Among the ecological science community, the consensus view is that the natural flow regime sustains the ecological integrity of river systems. This prevailing viewpoint by many environmental stakeholders has progressively led to increased pressure on hydropower dam owners to change plant operations to affect downstream river flows with the intention of providing better conditions for aquatic biological communities. Identifying the neccessary magnitude, frequency, duration, timing, or rate of change of stream flows to meet ecological needs in a hydropower context is challenging because the ecological responses to changes in flows may not be fully known, there are usually a multitude of competing users of flow, and implementing environmental flows usually comes at a price to energy production. Realistically, hydropower managers must develop a reduced set of goals that provide the most benefit to the identified ecological needs. As a part of the Department of Energy (DOE) Water Power Program, the Instream Flow Project (IFP) was carried out by Oak Ridge National Laboratory (ORNL), Pacific Northwest National Laboratory (PNNL), and Argon National Laboratory (ANL) as an attempt to develop tools aimed at defining environmental flow needs for hydropower operations. The application of these tools ranges from national to site-specific scales; thus, the utility of each tool will depend on various phases of the environmental flow process. Given the complexity and sheer volume of applications used to determine environmentally acceptable flows for hydropower, a framework is needed to organize efforts into a staged process dependent upon spatial, temporal, and functional attributes. By far, the predominant domain for determining environmental flows related to hydropower is within the Federal Energy Regulatory Commission (FERC) relicensing process. This process can take multiple years and can be very expensive depending on the scale of each hydropower project. The utility of such a framework is that it can expedite the environmental flow process by 1) organizing data and applications to identify predictable relationships between flows and ecology, and 2) suggesting when and where tools should be used in the environmental flow process. In addition to regulatory procedures, a framework should also provide the coordination for a comprehensive research agenda to guide the science of environmental flows. This research program has further reaching benefits than just environmental flow determination by providing modeling applications, data, and geospatial layers to inform potential hydropower development. We address several objectives within this document that highlight the limitations of existing environmental flow paradigms and their applications to hydropower while presenting a new framework catered towards hydropower needs. Herein, we address the following objectives: 1) Provide a brief overview of the Natural Flow Regime paradigm and existing environmental flow frameworks that have been used to determine ecologically sensitive stream flows for hydropower operations. 2) Describe a new conceptual framework to aid in determining flows needed to meet ecological objectives with regard to hydropower operations. The framework is centralized around determining predictable relationships between flow and ecological responses. 3) Provide evidence of how efforts from ORNL, PNNL, and ANL have filled some of the gaps in this broader framework, and suggest how the framework can be used to set the stage for a research agenda for environmental flow.

  17. A study of grout flow pattern analysis

    SciTech Connect (OSTI)

    Lee, S. Y. [Savannah River National Lab., Aiken, SC (United States); Hyun, S. [Mercer Univ., Macon, GA (United States)

    2013-01-10T23:59:59.000Z

    A new disposal unit, designated as Salt Disposal Unit no. 6 (SDU6), is being designed for support of site accelerated closure goals and salt nuclear waste projections identified in the new Liquid Waste System plan. The unit is cylindrical disposal vault of 380 ft diameter and 43 ft in height, and it has about 30 million gallons of capacity. Primary objective was to develop the computational model and to perform the evaluations for the flow patterns of grout material in SDU6 as function of elevation of grout discharge port, and slurry rheology. A Bingham plastic model was basically used to represent the grout flow behavior. A two-phase modeling approach was taken to achieve the objective. This approach assumes that the air-grout interface determines the shape of the accumulation mound. The results of this study were used to develop the design guidelines for the discharge ports of the Saltstone feed materials in the SDU6 facility. The focusing areas of the modeling study are to estimate the domain size of the grout materials radially spread on the facility floor under the baseline modeling conditions, to perform the sensitivity analysis with respect to the baseline design and operating conditions such as elevation of discharge port, discharge pipe diameter, and grout properties, and to determine the changes in grout density as it is related to grout drop height. An axi-symmetric two-phase modeling method was used for computational efficiency. Based on the nominal design and operating conditions, a transient computational approach was taken to compute flow fields mainly driven by pumping inertia and natural gravity. Detailed solution methodology and analysis results are discussed here.

  18. Radial Inflow Gas Turbine Flow Path Design

    E-Print Network [OSTI]

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

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

  19. The Big Flow

    E-Print Network [OSTI]

    P. Sikivie

    2001-12-04T23:59:59.000Z

    The late infall of cold dark matter onto an isolated galaxy, such as our own, produces streams and caustics in its halo. The outer caustics are topological spheres whereas the inner caustics are rings. The self-similar model of galactic halo formation predicts that the caustic ring radii $a_n$ follow the approximate law $a_n \\sim 1/n$. In a study of 32 extended and well-measured external galactic rotation curves evidence was found for this law. In the case of the Milky Way, the locations of eight sharp rises in the rotation curve fit the prediction of the self-similar model at the 3% level. Moreover, a triangular feature in the IRAS map of the galactic plane is consistent with the imprint of a ring caustic upon the baryonic matter. These observations imply that the dark matter in our neighborhood is dominated by a single flow. Estimates of that flow's density and velocity vector are given.

  20. Structural power flow measurement

    SciTech Connect (OSTI)

    Falter, K.J.; Keltie, R.F.

    1988-12-01T23:59:59.000Z

    Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

  1. Using laboratory flow experiments and reactive chemical transport modeling for designing waterflooding of the Agua Fria Reservoir, Poza Rica-Altamira Field, Mexico

    E-Print Network [OSTI]

    Birkle, P.

    2009-01-01T23:59:59.000Z

    into the Agua Fría reservoir, data from laboratory flowChemical analytical data from reservoir water were appliedapplied as input data for initial reservoir conditions. In

  2. Convective heat flow probe

    DOE Patents [OSTI]

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

    1984-01-09T23:59:59.000Z

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

  3. Performance Analysis of an Annular Diffuser Under the Influence of a Gas Turbine Stage Exit Flow

    E-Print Network [OSTI]

    Blanco, Rafael Rodriguez

    2013-12-31T23:59:59.000Z

    In this investigation the performance of a gas turbine exhaust diffuser subject to the outlet flow conditions of a turbine stage is evaluated. Towards that goal, a fully three-dimensional computational analysis has been performed where several...

  4. Bubble behavior in subcooled flow boiling on surfaces of variable wettability

    E-Print Network [OSTI]

    Tow, Emily W

    2012-01-01T23:59:59.000Z

    Flow boiling is important in energy conversion and thermal management due to its potential for very high heat fluxes. By improving understanding of the conditions leading to bubble departure, surfaces can be designed that ...

  5. Fluid Flow In The Resurgent Dome Of Long Valley Caldera- Implications...

    Open Energy Info (EERE)

    caldera was cooled to normal thermal conditions by vigorous hydrothermal activity in the past, and that a present-day hot water flow system is responsible for local hot anomalies,...

  6. Green Water Flow Kinematics and Impact Pressure on a Three Dimensional Model Structure

    E-Print Network [OSTI]

    Ariyarathne, Hanchapola Appuhamilage Kusalika Suranjani

    2011-10-21T23:59:59.000Z

    Flow kinematics of green water due to plunging breaking waves interacting with a simplified, three-dimensional model structure was investigated in laboratory. Two breaking wave conditions were tested: one with waves impinging and breaking...

  7. Undersampling to accelerate time-resolved MRI velocity measurement of carotid blood flow 

    E-Print Network [OSTI]

    Tao, Yuehui

    2009-01-01T23:59:59.000Z

    Time-resolved velocity information of carotid blood flow can be used to estimate haemodynamic conditions associated with carotid artery disease leading to stroke. MRI provides high-resolution measurement of such information ...

  8. Speed-up of combustion fronts in shear flows

    E-Print Network [OSTI]

    Hamel, Francois

    2011-01-01T23:59:59.000Z

    This paper is concerned with the analysis of speed-up of reaction-diffusion-advection traveling fronts in infinite cylinders with periodic boundary conditions. The advection is a shear flow with a large amplitude and the reaction is nonnegative, with either positive or zero ignition temperature. The unique or minimal speeds of the traveling fronts are proved to be asymptotically linear in the flow amplitude as the latter goes to infinity, solving an open problem from \\cite{b}. The asymptotic growth rate is characterized explicitly as the unique or minimal speed of traveling fronts for a limiting degenerate problem, and the convergence of the regular traveling fronts to the degenerate ones is proved for positive ignition temperatures under an additional H{\\"{o}}rmander-type condition on the flow.

  9. Equivalent Roughness Height for Plane Bed under Steady Flow

    E-Print Network [OSTI]

    US Army Corps of Engineers

    current conditions. In general, owing to dimensional reasons, the bed roughness height of a flat and fixed orders of magnitude larger than for a fixed bed. This is probably caused by the increased energyEquivalent Roughness Height for Plane Bed under Steady Flow Benoît Camenen, Ph.D.1 ; Atilla Bayram

  10. Analysis of Transient Processes in a Radiophysical Flow System

    E-Print Network [OSTI]

    E. N. Egorov; A. A. Koronovskii; A. E. Hramov

    2006-01-31T23:59:59.000Z

    Transient processes in a third-order radiophysical flow system are studied and a map of the transient process duration versus initial conditions is constructed and analyzed. The results are compared to the arrangement of submanifolds of the stable and unstable cycles in the Poincare section of the system studied.

  11. Split-flow regeneration in absorptive air separation

    DOE Patents [OSTI]

    Weimer, Robert F. (Allentown, PA)

    1987-01-01T23:59:59.000Z

    A chemical absorptive separation of air in multiple stage of absorption and desorption is performed with partial recycle of absorbent between stages of desorption necessary to match equilibrium conditions in the various stages of absorption. This allows reduced absorbent flow, reduced energy demand and reduced capital costs.

  12. Split-flow regeneration in absorptive air separation

    DOE Patents [OSTI]

    Weimer, R.F.

    1987-11-24T23:59:59.000Z

    A chemical absorptive separation of air in multiple stage of absorption and desorption is performed with partial recycle of absorbent between stages of desorption necessary to match equilibrium conditions in the various stages of absorption. This allows reduced absorbent flow, reduced energy demand and reduced capital costs. 4 figs.

  13. MATERIALS AND INFORMATION FLOWS FOR HVAC DUCTWORK FABRICATION AND SITE

    E-Print Network [OSTI]

    Tommelein, Iris D.

    MATERIALS AND INFORMATION FLOWS FOR HVAC DUCTWORK FABRICATION AND SITE INSTALLATION Matt Holzemer,1, and air-conditioning (HVAC) systems requires a set of complex activities and handoffs between multiple architecture-, engineering-, and construction practitioners. This paper highlights one part of the HVAC

  14. Plastic flow in solids with interfaces

    E-Print Network [OSTI]

    Anurag Gupta; David Steigmann

    2011-11-25T23:59:59.000Z

    A non-equilibrium theory of isothermal and diffusionless evolution of incoherent interfaces within a plastically deforming solid is developed. The irreversible dynamics of the interface are driven by its normal motion, incoherency (slip and misorientation), and an intrinsic plastic flow; and purely by plastic deformation in the bulk away from the interface. Using the continuum theory for defect distribution (in bulk and over the interface) we formulate a general kinematical framework, derive relevant balance laws and jump conditions, and prescribe a thermodynamically consistent constitutive/kinetic structure for interface evolution.

  15. Intermittency as a precursor to self Unsteady combustion in a confined, compressible flow

    E-Print Network [OSTI]

    Shyamasundar, R.K.

    , gas turbine engines generation, as well as rocket engines used for space exploration and defense conditions, when the underlying flow field inside the combustion chamber is turbulent. It was observed, a mechanism was proposed which necessitates that when the underlying flow transition to combustion instability

  16. INTERNATIONAL CONGRESS OF THE AERONAUTICAL SCIENCES Hypersonic flows of argon, nitrogen, oxygen,

    E-Print Network [OSTI]

    Riabov, Vladimir V.

    the Direct Simulation Monte-Carlo (DSMC) technique under transition rarefied-gas flow conditions (Knudsen structure (the shape of shock waves and the stagnation point location), skin friction, pressure distribution and gas mixtures were used in simulations of planetary atmospheres. The flow pattern near a torus in argon

  17. Air flow and particle control with different ventilation systems in a classroom

    E-Print Network [OSTI]

    Chen, Qingyan "Yan"

    Air flow and particle control with different ventilation systems in a classroom Sture Holmberg, Ph@mit.edu Phone: +1-617-253-7714, Fax: +1-617-2536152 Abstract Most ventilation and air conditioning systems. For displacement ventilation systems, designers normally assume that all pollutants follow the buoyant air flow

  18. The gradient flow running coupling in SU2 with 8 flavors

    E-Print Network [OSTI]

    Jarno Rantaharju; Tuomas Karavirta; Viljami Leino; Teemu Rantalaiho; Kari Rummukainen; Kimmo Tuominen

    2014-11-18T23:59:59.000Z

    We present preliminary results of the gradient flow running coupling with Dirichlet boundary condition in the SU(2) gauge theory with 8 fermion flavours. Improvements to the gradient flow measurement allow us to obtain a robust continuum limit. The results are consistent with perturbative running in the weak coupling region.

  19. Energy-Efficient Variable-Flow Liquid Cooling in 3D Stacked Architectures

    E-Print Network [OSTI]

    Simunic, Tajana

    1 Energy-Efficient Variable-Flow Liquid Cooling in 3D Stacked Architectures Ayse K. Coskun , David not fully utilized. Thus, it is not energy-efficient to adjust the coolant flow rate based on the worst-case conditions, as this would cause an excess in pump power. For energy-efficient cooling, we propose a novel

  20. Relative Changes of Cerebral Arterial and Venous Blood Volumes During Increased Cerebral Blood Flow

    E-Print Network [OSTI]

    Duong, Timothy Q.

    Relative Changes of Cerebral Arterial and Venous Blood Volumes During Increased Cerebral Blood Flow-Gi Kim1* Measurement of cerebral arterial and venous blood volumes during increased cerebral blood flow, and neuronally active conditions. In particular, the change in venous blood volume induced by neural activity

  1. CORIOLIS EFFECTS IN MESOSCALE SHALLOW LAYER FLOWS J. C. R. Hunt

    E-Print Network [OSTI]

    Hunt, Julian

    CORIOLIS EFFECTS IN MESOSCALE SHALLOW LAYER FLOWS J. C. R. Hunt ˘ˇ Ł ,A. Orr , D. Cresswell layer or inversion layer, is developed for idealised and steady, but typical, mesoscale atmospheric estimates for a wide range of perturbed mesoscale flows, especially where the surface conditions change

  2. The hydraulics of exchange flow between adjacent confined building zones Saleh Nabi*, M.R. Flynn

    E-Print Network [OSTI]

    Flynn, Morris R.

    2012 Keywords: Buoyancy-driven exchange flow Boussinesq flow Natural ventilation Plumes Gravity with an adjacent volume of ambient fluid is a common problem in fluid mechanics with numerous examples in natural for the design of HVAC (heating, ventilation, and air conditioning) systems or for increasing the efficiency

  3. Report on Hydrologic Flow in Low-Permeability Media

    SciTech Connect (OSTI)

    Liu, Hui-Hai; Birkholzer, Jens

    2013-11-13T23:59:59.000Z

    We demonstrate that under normal conditions (under which there are no intersections between tunnels/drifts and conductive geological structures, such as faults), the water flow velocity in the damage zone, as a result of non-Darcian flow behavior, is extremely small such that solute transport is dominated by diffusion, rather than advection. We show that unless non-Darcian flow behavior is considered, significant errors can occur in the “measured” relative-permeability values. We propose a hypothesis to consider the temperature impact based on limited test results from the petroleum literature. To consider the bedding effects, we present an empirical relationship between water flux and hydraulic gradient for non-Darcian water flow in anisotropic cases.

  4. Polymer brush under flow as an anchored microswimmer

    E-Print Network [OSTI]

    Biagi, Sofia; Sciortino, Francesco; Misbah, Chaouqi

    2015-01-01T23:59:59.000Z

    Polymer brushes are increasingly used to tailor surface physicochemistry for various applications such as wetting, adhesion of biological objects, implantable devices, etc. We perform Dissipative Particle Dynamics simulations to study the behavior of dense polymer brushes under flow in a slit-pore channel. We discover that the system displays flow inversion at the brush interface for several disconnected ranges of the imposed flow. We associate such phenomenon to collective polymer dynamics: a wave propagating on the brush surface. The relation between the wavelength, the amplitude and the propagation speed of the flow-generated wave is consistent with the solution of the Stokes equations when an imposed traveling wave is assumed as boundary condition (the famous Taylor's swimmer).

  5. Importance of Design Conditions for Sizing Air-Conditioning Plant

    E-Print Network [OSTI]

    Shaban, N.; Maheshwari, G. P.; Suri, R. K.

    2000-01-01T23:59:59.000Z

    Design conditions based on the meteorological data collected at two weather stations located less than 10 km away from each other within Kuwait City are presented for dry-bulb temperature (DBT) and web-bulb temperature (WBT) prioritization...

  6. Money versus Time: Evaluation of Flow Control in Terms of Energy Consumption and Convenience

    E-Print Network [OSTI]

    Frohnapfel, Bettina; Quadrio, Maurizio

    2012-01-01T23:59:59.000Z

    Flow control with the goal of reducing the skin friction drag on the fluid-solid interface is an active fundamental research area, motivated by its potential for significant energy savings and reduced emissions in the transport sector. Customarily, the performance of drag reduction techniques in internal flows is evaluated under two alternative flow conditions, i.e. at constant mass flow rate or constant pressure gradient. Successful control leads to reduction of drag and pumping power within the former approach, whereas the latter leads to an increase of the mass flow rate and pumping power. In practical applications, however, money and time define the flow control challenge: a compromise between the energy expenditure (money) and the corresponding convenience (flow rate) achieved with that amount of energy has to be reached so as to accomplish a goal which in general depends on the specific application. Based on this idea, we derive two dimensionless parameters which quantify the total energy consumption an...

  7. Energy conditions and supernovae observations

    SciTech Connect (OSTI)

    Santos, J. [Departamento de Fisica, Universidade Federal do Rio Grande do Norte, C.P. 1641, 59072-970 Natal - RN (Brazil); Alcaniz, J. S. [Departamento de Astronomia, Observatorio Nacional, 20921-400, Rio de Janeiro - RJ (Brazil); Reboucas, M. J. [Centro Brasileiro de Pesquisas Fisicas, 22290-180 Rio de Janeiro - RJ (Brazil)

    2006-09-15T23:59:59.000Z

    In general relativity, the energy conditions are invoked to restrict general energy-momentum tensors T{sub {mu}}{sub {nu}} on physical grounds. We show that in the standard Friedmann-Lemaitre-Robertson-Walker (FLRW) approach to cosmological modeling where the equation of state of the cosmological fluid is unknown, the energy conditions provide model-independent bounds on the behavior of the distance modulus of cosmic sources as a function of the redshift. We use both the gold and the legacy samples of current type Ia supenovae to carry out a model-independent analysis of the energy conditions violation in the context of standard cosmology.

  8. Simultaneous Extrema in the Entropy Production for Steady-State Fluid Flow in Parallel Pipes

    E-Print Network [OSTI]

    Niven, Robert K

    2009-01-01T23:59:59.000Z

    Steady-state flow of an incompressible fluid in parallel pipes can simultaneously satisfy two contradictory extremum principles in the entropy production, depending on the flow conditions. For a constant total flow rate, the flow can satisfy (i) a pipe network minimum entropy production (MinEP) principle with respect to the flow rates, and (ii) the maximum entropy production (MaxEP) principle of Paltridge and Ziegler with respect to the choice of flow regime. The first principle - different to but allied to that of Prigogine - arises from the stability of the steady state compared to non-steady-state flows; it is proven for isothermal laminar and turbulent flows in parallel pipes with a constant power law exponent, but is otherwise invalid. The second principle appears to be more fundamental, driving the formation of turbulent flow in single and parallel pipes at higher Reynolds numbers. For constant head conditions, the flow can satisfy (i) a modified maximum entropy production (MaxEPMod) principle of \\v{Z}u...

  9. Complex Flow Workshop Report

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the YouTube platformBuildingCoalComplex Flow Workshop Report January 17-18, 2012 University

  10. Non-axisymmetric Flows

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for Renewable Energy:Nanowire Solar541,9337,2AprilBig EddyNobelNon-axisymmetric Flows and

  11. Energetic materials at extreme conditions 

    E-Print Network [OSTI]

    Millar, David Iain Archibald

    2011-06-27T23:59:59.000Z

    In order to effectively model the behaviour of energetic materials under operational conditions it is essential to obtain detailed structural information for these compounds at elevated temperature and/or pressures. The ...

  12. Desire, belief, and conditional belief

    E-Print Network [OSTI]

    Etlin, David Jeffrey

    2008-01-01T23:59:59.000Z

    This dissertation studies the logics of value and conditionals, and the question of whether they should be given cognitivist analyses. Emotivist theories treat value judgments as expressions of desire, rather than beliefs ...

  13. Energy conditions and cosmic acceleration

    SciTech Connect (OSTI)

    Santos, J. [Universidade Federal do Rio Grande do Norte, Departamento de Fisica, C.P. 1641, 59072-970 Natal, RN (Brazil); Departamento de Astronomia, Observatorio Nacional, 20921-400, Rio de Janeiro, RJ (Brazil); Centro Brasileiro de Pesquisas Fisicas, 22290-180, Rio de Janeiro, RJ (Brazil); Alcaniz, J. S. [Departamento de Astronomia, Observatorio Nacional, 20921-400, Rio de Janeiro, RJ (Brazil); Pires, N. [Universidade Federal do Rio Grande do Norte, Departamento de Fisica, C.P. 1641, 59072-970 Natal, RN (Brazil); Reboucas, M. J. [Centro Brasileiro de Pesquisas Fisicas, 22290-180, Rio de Janeiro, RJ (Brazil)

    2007-04-15T23:59:59.000Z

    In general relativity, the energy conditions are invoked to restrict general energy-momentum tensors T{sub {mu}}{sub {nu}} in different frameworks, and to derive general results that hold in a variety of general contexts on physical grounds. We show that in the standard Friedmann-Lemaitre-Robertson-Walker (FLRW) approach, where the equation of state of the cosmological fluid is unknown, the energy conditions provide model-independent bounds on the behavior of the distance modulus of cosmic sources as a function of the redshift for any spatial curvature. We use the most recent type Ia supernovae (SNe Ia) observations, which include the new Hubble Space Telescope SNe Ia events, to carry out a model-independent analysis of the energy conditions violation in the context of the standard cosmology. We show that both the null (NEC), weak (WEC), and dominant (DEC) conditions, which are associated with the existence of the so-called phantom fields, seem to have been violated only recently (z < or approx. 0.2), whereas the condition for attractive gravity, i.e., the strong energy condition (SEC) was first violated billions of years ago, at z > or approx. 1.

  14. Parameter Estimation of Dynamic Air-conditioning Component Models Using Limited Sensor Data

    E-Print Network [OSTI]

    Hariharan, Natarajkumar

    2011-08-08T23:59:59.000Z

    .1). ?? , is the area of orifice opening and ?? is the coefficient of discharge of the expansion valve at that specific condition. Coefficient of discharge is a dependent on the EEV geometry and the thermal?fluid properties of the refrigerant flowing through... Area of application of bulb pressure ?2 Area of application of evaporator pressure ?? External surface area of the TEV bulb ??? Area of heat conduction between the refrigerant and the bulb ?? Area of opening for refrigerant flow in expansion...

  15. Fluid flow monitoring device

    DOE Patents [OSTI]

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

    1993-11-30T23:59:59.000Z

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

  16. Fluid flow monitoring device

    DOE Patents [OSTI]

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

    1993-01-01T23:59:59.000Z

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

  17. Radial flow heat exchanger

    DOE Patents [OSTI]

    Valenzuela, Javier (Hanover, NH)

    2001-01-01T23:59:59.000Z

    A radial flow heat exchanger (20) having a plurality of first passages (24) for transporting a first fluid (25) and a plurality of second passages (26) for transporting a second fluid (27). The first and second passages are arranged in stacked, alternating relationship, are separated from one another by relatively thin plates (30) and (32), and surround a central axis (22). The thickness of the first and second passages are selected so that the first and second fluids, respectively, are transported with laminar flow through the passages. To enhance thermal energy transfer between first and second passages, the latter are arranged so each first passage is in thermal communication with an associated second passage along substantially its entire length, and vice versa with respect to the second passages. The heat exchangers may be stacked to achieve a modular heat exchange assembly (300). Certain heat exchangers in the assembly may be designed slightly differently than other heat exchangers to address changes in fluid properties during transport through the heat exchanger, so as to enhance overall thermal effectiveness of the assembly.

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

    SciTech Connect (OSTI)

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

    1985-10-01T23:59:59.000Z

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

  19. Active combustion flow modulation valve

    DOE Patents [OSTI]

    Hensel, John Peter; Black, Nathaniel; Thorton, Jimmy Dean; Vipperman, Jeffrey Stuart; Lambeth, David N; Clark, William W

    2013-09-24T23:59:59.000Z

    A flow modulation valve has a slidably translating hollow armature with at least one energizable coil wound around and fixably attached to the hollow armature. The energizable coil or coils are influenced by at least one permanent magnet surrounding the hollow armature and supported by an outer casing. Lorentz forces on the energizable coils which are translated to the hollow armature, increase or decrease the flow area to provide flow throttling action. The extent of hollow armature translation depends on the value of current supplied and the direction of translation depends on the direction of current flow. The compact nature of the flow modulation valve combined with the high forces afforded by the actuator design provide a flow modulation valve which is highly responsive to high-rate input control signals.

  20. Range Condition: Key to Sustained Ranch Productivity

    E-Print Network [OSTI]

    McGinty, Allan; White, Larry D.

    2000-04-25T23:59:59.000Z

    Range condition, or a rangeland's "state of health," is an ecological measurement of the current condition of a range. Range condition is evaluated by the plant species composition. This leaflet explains the importance of range condition, how range...

  1. Conditioned changes in pain reactivity: conditioned stimuli elicit hypoalgesia under a wide range of test conditions

    E-Print Network [OSTI]

    Illich, Paul Anthony

    1990-01-01T23:59:59.000Z

    conditioned hypoalgesia, two recent reports suggest that a conditioned stimulus (CS) which has been paired with an aversive event may sometimes produce an increase in pain reactivity, or "hyperalgesia" rather than hypoalgesia (Davis & Henderson, 1985...-Evans hooded rats) (Davis & Henderson, 1985; Lysle & Fowler, 1988). Currently, it is not clear what determines whether a stimulus which has been paired with an aversive event will elicit either an increase or decrease in pain reactivity. In the present...

  2. Experimental and theoretical studies of the effects of nonuniformities in nonequilibrium magnetohydrodynamic flows

    SciTech Connect (OSTI)

    Lytle, J.K.; Louis, J.F.

    1984-07-01T23:59:59.000Z

    A study of wake nonuniformities in a nonequilibrium magnetohydrodynamic plasma is described. Experimental results are presented from an electrodeless disk-shaped channel in both radial flow and swirl flow configurations. The experimental conditions are analyzed with a nonequilibrium plasma model that accounts for variations in the wake gas properties and wake width. The results show that the wake nonuniformities in the radial flow channel are weak, but in the swirl flow channel they are strong because of an instability. This instability is a consequence of the wake orientation. Furthermore, the intensity of the nonuniformity in an unstable plasma is dependent upon the wake gas velocity and wake width.

  3. Two phase flow in geothermal systems. Final report, April 1, 1984-March 31, 1985

    SciTech Connect (OSTI)

    Maeder, P.F.; Kestin, J.

    1985-04-01T23:59:59.000Z

    Studies were performed to better understand the physical mechanisms involved in two-phase, single substance flow and their thermodynamic and fluid-dynamic implications. Flow properties were measured over a wide range of flow conditions from low-flash Mach number to high-flash Mach numbers to simulate actual two-phase flow over the full length of a geothermal well from the flash horizon to the choked wellhead. Void fraction, friction factors and entropy production were calculated. 2 refs., 12 figs. (ACR)

  4. Method and apparatus for controlling the flow rate of mercury in a flow system

    SciTech Connect (OSTI)

    Grossman, M.W.; Speer, R.

    1991-01-01T23:59:59.000Z

    This patent describes a process for increasing the mercury flow rate {ital Q{sub Hg}} to a photochemical mercury enrichment process. It comprises: utilizing an entrainment system having a temperature regulated pool of mercury, a bubbler or sparger system, and a carrier gas for entraining mercury vapor; passing the carrier gas over a pool of mercury maintained at a first temperature, T{sub 1} wherein the carrier gas entrains mercury vapor; and passing the mercury vapor entrained carrier gas to a second temperature zone, maintained at a temperature T{sub 2}, such that T{sub 2} is less than T{sub 1}, in which the entrained mercury vapor is condensed, thereby producing a saturated Hg conditioning the carrier gas; and passing the saturated Hg carrier gas to the photochemical enrichment reactor, yielding a high flow rate {ital Q{sub Hg}}.

  5. Laminar and turbulent nozzle-jet flows and their acoustic near-field

    SciTech Connect (OSTI)

    Bühler, Stefan; Obrist, Dominik; Kleiser, Leonhard [Institute of Fluid Dynamics, ETH Zurich, 8092 Zurich (Switzerland)

    2014-08-15T23:59:59.000Z

    We investigate numerically the effects of nozzle-exit flow conditions on the jet-flow development and the near-field sound at a diameter-based Reynolds number of Re{sub D} = 18?100 and Mach number Ma = 0.9. Our computational setup features the inclusion of a cylindrical nozzle which allows to establish a physical nozzle-exit flow and therefore well-defined initial jet-flow conditions. Within the nozzle, the flow is modeled by a potential flow core and a laminar, transitional, or developing turbulent boundary layer. The goal is to document and to compare the effects of the different jet inflows on the jet flow development and the sound radiation. For laminar and transitional boundary layers, transition to turbulence in the jet shear layer is governed by the development of Kelvin-Helmholtz instabilities. With the turbulent nozzle boundary layer, the jet flow development is characterized by a rapid changeover to a turbulent free shear layer within about one nozzle diameter. Sound pressure levels are strongly enhanced for laminar and transitional exit conditions compared to the turbulent case. However, a frequency and frequency-wavenumber analysis of the near-field pressure indicates that the dominant sound radiation characteristics remain largely unaffected. By applying a recently developed scaling procedure, we obtain a close match of the scaled near-field sound spectra for all nozzle-exit turbulence levels and also a reasonable agreement with experimental far-field data.

  6. Longitudinal Decorrelation of Anisotropic Flows in Heavy-ion Collisions at the CERN Large Hadron Collider

    E-Print Network [OSTI]

    Long-Gang Pang; Guang-You Qin; Victor Roy; Xin-Nian Wang; Guo-Liang Ma

    2015-04-22T23:59:59.000Z

    Fluctuations in the initial transverse energy-density distribution lead to anisotropic flows as observed in central high-energy heavy-ion collisions. Studies of longitudinal fluctuations of the anisotropic flows can shed further light on the initial conditions and dynamical evolution of the hot quark-gluon matter in these collisions. Correlations between anisotropic flows with varying pseudorapidity gaps in Pb+Pb collisions at the CERN Large Hadron Collider are investigated using both an event-by-event (3+1)-D ideal hydrodynamical model with fluctuating initial conditions and the a multiphase transport (AMPT) Monte Carlo model for high-energy heavy-ion collisions. Anisotropic flows at different pseudorapidities are found to become significantly decorrelated with increasing pseudo-rapidity gaps due to longitudinal fluctuations in the initial states of heavy-ion collisions. The longitudinal correlation of the elliptic flow shows a strong centrality dependence while the correlation of the triangular flow is independent of the centrality. Longitudinal fluctuations as a source of the decorrelation are further shown to consist of a twist or gradual rotation in flow angles between the forward and backward direction and additional fluctuations on top of the twist. Within the AMPT model, longitudinal correlations of anisotropic flows are also found to depend on the value of partonic cross sections. The implicatiosn of constraining the initial conditions and shear viscosity to entropy density ratio of the partonic matter in high-energy heavy-ion collisions are also discussed.

  7. Subsurface Flow and Transport | EMSL

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

    subsurface related to contaminant transport, carbon cycling, enhanced oil recovery and carbon dioxide sequestration. See a complete list of Subsurface Flow and Transport...

  8. Generalized Solovev equilibrium with sheared flow of arbitrary direction and stability consideration

    SciTech Connect (OSTI)

    Kaltsas, D. A., E-mail: dkaltsas@cc.uoi.gr, E-mail: gthroum@cc.uoi.gr; Throumoulopoulos, G. N., E-mail: dkaltsas@cc.uoi.gr, E-mail: gthroum@cc.uoi.gr [Department of Physics, University of Ioannina, GR 451 10 Ioannina (Greece)

    2014-08-15T23:59:59.000Z

    A Solovev-like solution describing equilibria with field aligned incompressible flows [G. N. Throumoulopoulos and H. Tasso, Phys. Plasmas 19, 014504 (2012)] is extended to non parallel flows. The solution expressed as a superposition of Bessel functions contains an arbitrary number of free parameters which are exploited to construct a variety of configurations including ITER shaped ones. For parallel flows, application of a sufficient condition for linear stability shows that this condition is satisfied in an appreciable part of the plasma region on the high-field side mostly due to the variation of the magnetic field perpendicular to the magnetic surfaces. Also, the results indicate that depending on the shape of the Mach-function profile and the values of the free parameters the flow and flow shear may have either stabilizing or destabilizing effects.

  9. Thermonuclear Fusion with the Sheared Flow Stabilized Z-Pinch

    E-Print Network [OSTI]

    Winterberg, F

    2008-01-01T23:59:59.000Z

    Two basic approaches to producing thermonuclear fusion with a sheared flow stabilized z-pinch are considered. One consists of heating the entire length of the z-pinch column to the required temperatures. The other basic approach considered here involves the concept of fast ignition. A localized "hot-spot" is produced under the proper conditions to ignite a thermonuclear burn wave in the z-pinch plasma. Here we demonstrate that sheared flow stabilization is more efficient in the fast-ignition method with isentropic compression then in a z-pinch where the entire plasma column is heated.

  10. hal-00145315,version3-2Aug2007 Viscous potential free-surface flows in a fluid layer of finite depth

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ´equations. Key words: potential flow, free-surface flow, viscosity, dissipation, water waves, wave damping-surface elevation. A new predominant nonlocal viscous term is derived in the bottom kinematic boundary condition potential flow theories [7]. Corresponding long wave model equations are derived. R´esum´e Ecoulements

  11. Rényi entropy flows from quantum heat engines

    E-Print Network [OSTI]

    Mohammad H. Ansari; Yuli V. Nazarov

    2015-03-20T23:59:59.000Z

    We evaluate Renyi entropy flows from generic quantum heat engines (QHE) to a weakly-coupled probe environment kept in thermal equilibrium. We show that the flows are determined not only by heat flow but also by a quantum coherent flow that can be separately measured in experiment apart from the heat flow measurement. The same pertains to Shanon entropy flow. This appeals for a revision of the concept of entropy flows in quantum nonequlibrium thermodynamics.

  12. Changes in high cloud conditions

    E-Print Network [OSTI]

    Himebrook, Richard Frank

    1974-01-01T23:59:59.000Z

    ). When the effect of unknowns is added to the data (Figs. 3(a) and 3(b), p, 21), the period with most high-cloud cover seems to alter- nate back and forth almost monthly, The average, global, solar radiation (Fig. 3(c), p. 21) depicts a decrease from... radiation, per cent possible sunshine, and average sky cover. The increases in high-cloud cover occurred in areas with the following characteristics: strong upper-air flow; frequent jet ' aircraft traffic; coverage of less than half the sky; late...

  13. Extreme Conditions Modeling Workshop Report

    SciTech Connect (OSTI)

    Coe, R. G.; Neary, V. S.; Lawson, M. J.; Yu, Y.; Weber, J.

    2014-07-01T23:59:59.000Z

    Sandia National Laboratories (SNL) and the National Renewable Energy Laboratory (NREL) hosted the Wave Energy Converter (WEC) Extreme Conditions Modeling (ECM) Workshop in Albuquerque, NM on May 13th-14th, 2014. The objective of the workshop was to review the current state of knowledge on how to model WECs in extreme conditions (e.g. hurricanes and other large storms) and to suggest how U.S. Department of Energy (DOE) and national laboratory resources could be used to improve ECM methods for the benefit of the wave energy industry.

  14. Conditions for successful data assimilation

    E-Print Network [OSTI]

    Alexandre J. Chorin; Matthias Morzfeld

    2014-10-22T23:59:59.000Z

    We show, using idealized models, that numerical data assimilation can be successful only if an effective dimension of the problem is not excessive. This effective dimension depends on the noise in the model and the data, and in physically reasonable problems it can be moderate even when the number of variables is huge. We then analyze several data assimilation algorithms, including particle filters and variational methods. We show that well-designed particle filters can solve most of those data assimilation problems that can be solved in principle, and compare the conditions under which variational methods can succeed to the conditions required of particle filters. We also discuss the limitations of our analysis.

  15. Reversing Flow Test Facility. Technical report, March 1986

    SciTech Connect (OSTI)

    Roach, P.D.

    1986-04-01T23:59:59.000Z

    The Reversing Flow Test Facility (RFTF) is intended for the study of fluid flow and heat transfer under the reversing-flow conditions that occur in Stirling engines. the facility consists of four major parts: (1) Mechanical Drive - two cylinders with cam-driven pistons which generate the reversing gas flow, (2) Test Section - a U-shaped section containing instrumented test pieces, (3) Instruments -l high-speed transducers for measuring gas pressure and temperature, piston positions, and other system parameters, and (4) Data Acquisition System - a computer-based system able to acquire, store, display and analyze the data from the instruments. The RFTF can operate at pressures up to 8.0 MPa, hot-side temperatures to 800/sup 0/C, and flow-reversal frequencies to 50 Hz. Operation to data has used helium as the working gas at pressures of 3.0 and 6.0 MPa, at ambient temperature, and at frequencies from 1 to 50 Hz. The results show that both frictional and inertial parts of the pressure drop are significant in the heater, coolers and connecting tubes; the inertial part is negligible in the regenerators. In all cases, the frictional part of the pressure drop is nearly in phase with the mass flow. 18 refs., 22 figs., 13 tabs.

  16. The magnetic flywheel flow meter: Theoretical and experimental contributions

    SciTech Connect (OSTI)

    Buchenau, D., E-mail: d.buchenau@hzdr.de; Galindo, V.; Eckert, S. [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics, Bautzner Landstraße 400, 01328 Dresden (Germany)

    2014-06-02T23:59:59.000Z

    The development of contactless flow meters is an important issue for monitoring and controlling of processes in different application fields, like metallurgy, liquid metal casting, or cooling systems for nuclear reactors and transmutation machines. Shercliff described in his book “The Theory of Electromagnetic Flow Measurement, Cambridge University Press, 1962” a simple and robust device for contact-less measurements of liquid metal flow rates which is known as magnetic flywheel. The sensor consists of several permanent magnets attached on a rotatable soft iron plate. This arrangement will be placed closely to the liquid metal flow to be measured, so that the field of the permanent magnets penetrates into the fluid volume. The flywheel will be accelerated by a Lorentz force arising from the interaction between the magnetic field and the moving liquid. Steady rotation rates of the flywheel can be taken as a measure for the mean flow rate inside the fluid channel. The present paper provides a detailed theoretical description of the sensor in order to gain a better insight into the functional principle of the magnetic flywheel. Theoretical predictions are confirmed by corresponding laboratory experiments. For that purpose, a laboratory model of such a flow meter was built and tested on a GaInSn-loop under various test conditions.

  17. Modelling of multiphase flow in ironmaking blast furnace

    SciTech Connect (OSTI)

    Dong, X.F.; Yu, A.B.; Burgess, J.M.; Pinson, D.; Chew, S.; Zulli, P. [University of New South Wales, Sydney, NSW (Australia). School for Material Science and Engineering

    2009-01-15T23:59:59.000Z

    A mathematical model for the four-phase (gas, powder, liquid, and solids) flow in a two-dimensional ironmaking blast furnace is presented by extending the existing two-fluid flow models. The model describes the motion of gas, solid, and powder phases, based on the continuum approach, and implements the so-called force balance model for the flow of liquids, such as metal and slag in a blast furnace. The model results demonstrate a solid stagnant zone and dense powder hold-up region, as well as a dense liquid flow region that exists in the lower part of a blast furnace, which are consistent with the experimental observations reported in the literature. The simulation is extended to investigate the effects of packing properties and operational conditions on the flow and the volume fraction distribution of each phase in a blast furnace. It is found that solid movement has a significant effect on powder holdup distribution. Small solid particles and low porosity distribution are predicted to affect the fluid flow considerably, and this can cause deterioration in bed permeability. The dynamic powder holdup in a furnace increases significantly with the increase of powder diameter. The findings should be useful to better understand and control blast furnace operations.

  18. Characterization of non-Darcy multiphase flow in petroleum bearing formations. Annual status report, May 14, 1991--May 13, 1992

    SciTech Connect (OSTI)

    Evans, R.D.; Civan, F.

    1992-12-31T23:59:59.000Z

    The objectives of this research are: Develop a proper theoretical model for characterizing non-Darcy multi-phase flow in petroleum bearing formations. Develop an experimental technique for measuring non-Darcy flow coefficients under multiphase flow at insitu reservoir conditions. Develop dimensional consistent correlations to express the non-Darcy flow coefficient as a function of rock and fluid properties for consolidated and unconsolidated porous media. The research accomplished during the period May 1991--May 1992 focused upon theoretical and experimental studies of multiphase non-Darcy flow in porous media.

  19. Introduction Simulation of Pathological conditions

    E-Print Network [OSTI]

    Willson, Stephen J.

    Reference Survey of the Modeling Brain Energy Metabolism and Function -- Report of the work by Larisa. V et State University MATH 690P, Dec. 1. 06 Wen Zhou Modeling Brain Energy #12;Outline Introduction Modeling Simulation of Pathological conditions Conclusion and Discussion Reference Introduction Modeling Energy

  20. Conditionally Independent Generalized Competing Risks

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    is subjected to corrective maintenance (CM) and condition-based preventive maintenance (PM) actions. In order into a state in which it can perform its function again. Preventive maintenance (PM) is carried out when whether the maintenance is preventive or correc- tive. 2. Characterization of the PM-CM process Let Ht

  1. Conditions of Occupancy College Residences

    E-Print Network [OSTI]

    O'Mahony, Donal E.

    Green and at Trinity Hall, Dartry, Dublin 6. There may be local differences in the Conditions of Occupancy between the main campus and Trinity Hall. Such differences will be described within to either the Warden of Trinity Hall in relation to rooms or residents at Trinity Hall or the Registrar

  2. Method and apparatus for controlling the flow rate of mercury in a flow system

    DOE Patents [OSTI]

    Grossman, Mark W. (Belmont, MA); Speer, Richard (Reading, MA)

    1991-01-01T23:59:59.000Z

    A method for increasing the mercury flow rate to a photochemical mercury enrichment utilizing an entrainment system comprises the steps of passing a carrier gas over a pool of mercury maintained at a first temperature T1, wherein the carrier gas entrains mercury vapor; passing said mercury vapor entrained carrier gas to a second temperature zone T2 having temperature less than T1 to condense said entrained mercury vapor, thereby producing a saturated Hg condition in the carrier gas; and passing said saturated Hg carrier gas to said photochemical enrichment reactor.

  3. Network Flow Optimization under Uncertainty

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    Network model in words Minimize the cost of satisfying demands for electric energy By: imports, exports and electricity Subject to: conservation of energy flows (net after losses), lower and upper bounds on flows is a reactive approach: how would the optimal solution have changed if I'd only known? · Proactive approaches

  4. Redox Flow Batteries, a Review

    SciTech Connect (OSTI)

    U. Tennessee Knoxville; U. Texas Austin; McGill U; Weber, Adam Z.; Mench, Matthew M.; Meyers, Jeremy P.; Ross, Philip N.; Gostick, Jeffrey T.; Liu, Qinghua

    2011-07-15T23:59:59.000Z

    Redox flow batteries are enjoying a renaissance due to their ability to store large amounts of electrical energy relatively cheaply and efficiently. In this review, we examine the components of redox flow batteries with a focus on understanding the underlying physical processes. The various transport and kinetic phenomena are discussed along with the most common redox couples.

  5. Wavy flow cooling concept for turbine airfoils

    DOE Patents [OSTI]

    Liang, George (Palm City, FL)

    2010-08-31T23:59:59.000Z

    An airfoil including an outer wall and a cooling cavity formed therein. The cooling cavity includes a leading edge flow channel located adjacent a leading edge of the airfoil and a trailing edge flow channel located adjacent a trailing edge of the airfoil. Each of the leading edge and trailing edge flow channels define respective first and second flow axes located between pressure and suction sides of the airfoil. A plurality of rib members are located within each of the flow channels, spaced along the flow axes, and alternately extending from opposing sides of the flow channels to define undulating flow paths through the flow channels.

  6. Vertical flow chemical detection portal

    DOE Patents [OSTI]

    Linker, K.L.; Hannum, D.W.; Conrad, F.J.

    1999-06-22T23:59:59.000Z

    A portal apparatus is described for screening objects or persons for the presence of trace amounts of chemical substances such as illicit drugs or explosives. The apparatus has a test space, in which a person may stand, defined by two generally upright sides spanned by a horizontal transom. One or more fans in the transom generate a downward air flow (uni-directional) within the test space. The air flows downwardly from a high pressure upper zone, past the object or person to be screened. Air moving past the object dislodges from the surface thereof both volatile and nonvolatile particles of the target substance. The particles are entrained into the air flow which continues flowing downward to a lower zone of reduced pressure, where the particle-bearing air stream is directed out of the test space and toward preconcentrator and detection components. The sides of the portal are specially configured to partially contain and maintain the air flow. 3 figs.

  7. Confined flow of suspensions modeled by a frictional rheology

    E-Print Network [OSTI]

    Brice Lecampion; Dmitry I. Garagash

    2014-09-19T23:59:59.000Z

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

  8. Recurrent flow analysis in spatiotemporally chaotic 2-dimensional Kolmogorov flow

    E-Print Network [OSTI]

    Dan Lucas; Rich Kerswell

    2015-04-01T23:59:59.000Z

    Motivated by recent success in the dynamical systems approach to transitional flow, we study the efficiency and effectiveness of extracting simple invariant sets (recurrent flows) directly from chaotic/turbulent flows and the potential of these sets for providing predictions of certain statistics of the flow. Two-dimensional Kolmogorov flow (the 2D Navier-Stokes equations with a sinusoidal body force) is studied both over a square [0, 2{\\pi}]2 torus and a rectangular torus extended in the forcing direction. In the former case, an order of magnitude more recurrent flows are found than previously (Chandler & Kerswell 2013) and shown to give improved predictions for the dissipation and energy pdfs of the chaos via periodic orbit theory. Over the extended torus at low forcing amplitudes, some extracted states mimick the statistics of the spatially-localised chaos present surprisingly well recalling the striking finding of Kawahara & Kida (2001) in low-Reynolds-number plane Couette flow. At higher forcing amplitudes, however, success is limited highlighting the increased dimensionality of the chaos and the need for larger data sets. Algorithmic developments to improve the extraction procedure are discussed.

  9. Variable Refrigerant Flow HVAC

    E-Print Network [OSTI]

    Jones, S.

    2013-01-01T23:59:59.000Z

    heat pump utilizing VFD Inverter Compressors and LEV’s Unlike conventional commercial and residential HVAC systems in the USA The predominate method of cooling and heating in the world ESL-KT-13-12-33 CATEE 2013: Clean Air Through Energy Efficiency... Conference, San Antonio, Texas Dec. 16-18 Heat Pump operation at lower ambient conditions -13 -4 5 17 23 32 41 470 0.2 0.4 0.6 0.8 1 1.2 Residential Heating Capacity at Low Temperatures MUZ-FE18NA MUZ-FE09NA MUZ-FE12NA Unitary Outdoor Temperature (F...

  10. Flow Rate Measurements Using Flow-Induced Pipe Vibration

    SciTech Connect (OSTI)

    R. P. Evans; Jonathan D. Blotter; Alan G. Stephens

    2004-03-01T23:59:59.000Z

    This paper focuses on the possibility of a non-intrusive, low cost, flow rate measurement technique. The technique is based on signal noise from an accelerometer attached to the surface of the pipe. The signal noise is defined as the standard deviation of the frequency averaged time series signal. Experimental results are presented that indicate a nearly quadratic relationship between the signal noise and mass flow rate in the pipe. It is also shown that the signal noise - flow rate relationship is dependant on the pipe material and diameter.

  11. Mutiscale Modeling of Segregation in Granular Flows

    SciTech Connect (OSTI)

    Jin Sun

    2007-08-03T23:59:59.000Z

    Modeling and simulation of segregation phenomena in granular flows are investigated. Computational models at different scales ranging from particle level (microscale) to continuum level (macroscale) are employed in order to determine the important microscale physics relevant to macroscale modeling. The capability of a multi-fluid model to capture segregation caused by density difference is demonstrated by simulating grain-chaff biomass flows in a laboratory-scale air column and in a combine harvester. The multi-fluid model treats gas and solid phases as interpenetrating continua in an Eulerian frame. This model is further improved by incorporating particle rotation using kinetic theory for rapid granular flow of slightly frictional spheres. A simplified model is implemented without changing the current kinetic theory framework by introducing an effective coefficient of restitution to account for additional energy dissipation due to frictional collisions. The accuracy of predicting segregation rate in a gas-fluidized bed is improved by the implementation. This result indicates that particle rotation is important microscopic physics to be incorporated into the hydrodynamic model. Segregation of a large particle in a dense granular bed of small particles under vertical. vibration is studied using molecular dynamics simulations. Wall friction is identified as a necessary condition for the segregation. Large-scale force networks bearing larger-than-average forces are found with the presence of wall friction. The role of force networks in assisting rising of the large particle is analyzed. Single-point force distribution and two-point spatial force correlation are computed. The results show the heterogeneity of forces and a short-range correlation. The short correlation length implies that even dense granular flows may admit local constitutive relations. A modified minimum spanning tree (MST) algorithm is developed to asymptotically recover the force statistics in the force networks. This algorithm provides a possible route to constructing a continuum model with microstructural information supplied from it. Microstructures in gas fluidized beds are also analyzed using a hybrid method, which couples the discrete element method (DEM) for particle dynamics with the averaged two-fluid (TF) equations for the gas phase. Multi-particle contacts are found in defluidized regions away from bubbles in fluidized beds. The multi-particle contacts invalidate the binary-collision assumption made in the kinetic theory of granular flows for the defluidized regions. Large ratios of contact forces to drag forces are found in the same regions, which confirms the relative importance of contact forces in determining particle dynamics in the defluidized regions.

  12. US energy flow - 1984

    SciTech Connect (OSTI)

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

    1985-07-01T23:59:59.000Z

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

  13. Turbulent patterns in wall-bounded flows: a Turing instability?

    E-Print Network [OSTI]

    Manneville, Paul

    2012-01-01T23:59:59.000Z

    In their way to/from turbulence, plane wall-bounded flows display an interesting transitional regime where laminar and turbulent oblique bands alternate, the origin of which is still mysterious. In line with Barkley's recent work about the pipe flow transition involving reaction-diffusion concepts, we consider plane Couette flow in the same perspective and transform Waleffe's classical four-variable model of self-sustaining process into a reaction-diffusion model. We show that, upon fulfillment of a condition on the relative diffusivities of its variables, the featureless turbulent regime becomes unstable against patterning as the result of a Turing instability. A reduced two-variable model helps us to delineate the appropriate region of parameter space. An {\\it intrinsic} status is therefore given to the pattern's wavelength for the first time. Virtues and limitations of the model are discussed, calling for a microscopic support of the phenomenological approach.

  14. Optimal Control of Transient Flow in Natural Gas Networks

    E-Print Network [OSTI]

    Zlotnik, Anatoly; Backhaus, Scott

    2015-01-01T23:59:59.000Z

    We outline a new control system model for the distributed dynamics of compressible gas flow through large-scale pipeline networks with time-varying injections, withdrawals, and control actions of compressors and regulators. The gas dynamics PDE equations over the pipelines, together with boundary conditions at junctions, are reduced using lumped elements to a sparse nonlinear ODE system expressed in vector-matrix form using graph theoretic notation. This system, which we call the reduced network flow (RNF) model, is a consistent discretization of the PDE equations for gas flow. The RNF forms the dynamic constraints for optimal control problems for pipeline systems with known time-varying withdrawals and injections and gas pressure limits throughout the network. The objectives include economic transient compression (ETC) and minimum load shedding (MLS), which involve minimizing compression costs or, if that is infeasible, minimizing the unfulfilled deliveries, respectively. These continuous functional optimiza...

  15. Condition assessment of nonlinear processes

    DOE Patents [OSTI]

    Hively, Lee M. (Philadelphia, TN); Gailey, Paul C. (Athens, OH); Protopopescu, Vladimir A. (Knoxville, TN)

    2002-01-01T23:59:59.000Z

    There is presented a reliable technique for measuring condition change in nonlinear data such as brain waves. The nonlinear data is filtered and discretized into windowed data sets. The system dynamics within each data set is represented by a sequence of connected phase-space points, and for each data set a distribution function is derived. New metrics are introduced that evaluate the distance between distribution functions. The metrics are properly renormalized to provide robust and sensitive relative measures of condition change. As an example, these measures can be used on EEG data, to provide timely discrimination between normal, preseizure, seizure, and post-seizure states in epileptic patients. Apparatus utilizing hardware or software to perform the method and provide an indicative output is also disclosed.

  16. Numerical Simulation of Inter-basin Groundwater Flow into Northern Yucca Flat, Nevada National Security Site, Using the Death Valley Regional Flow System Model

    SciTech Connect (OSTI)

    Pohlmann Karl,Ye Ming

    2012-03-01T23:59:59.000Z

    Models of groundwater flow for the Yucca Flat area of the Nevada National Security Site (NNSS) are under development by the U.S. Department of Energy (DOE) for corrective action investigations of the Yucca Flat-Climax Mine Corrective Action Unit (CAU). One important aspect of these models is the quantity of inter-basin groundwater flow from regional systems to the north. This component of flow, together with its uncertainty, must be properly accounted for in the CAU flow models to provide a defensible regional framework for calculations of radionuclide transport that will support determinations of the Yucca Flat-Climax Mine contaminant boundary. Because characterizing flow boundary conditions in northern Yucca Flat requires evaluation to a higher level of detail than the scale of the Yucca Flat-Climax Mine CAU model can efficiently provide, a study more focused on this aspect of the model was required.

  17. A Primer on Energy Conditions

    E-Print Network [OSTI]

    Erik Curiel

    2014-04-30T23:59:59.000Z

    An energy condition, in the context of a wide class of spacetime theories (including general relativity), is, crudely speaking, a relation one demands the stress-energy tensor of matter satisfy in order to try to capture the idea that "energy should be positive". The remarkable fact I will discuss in this paper is that such simple, general, almost trivial seeming propositions have profound and far-reaching import for our understanding of the structure of relativistic spacetimes. It is therefore especially surprising when one also learns that we have no clear understanding of the nature of these conditions, what theoretical status they have with respect to fundamental physics, what epistemic status they may have, when we should and should not expect them to be satisfied, and even in many cases how they and their consequences should be interpreted physically. Or so I shall argue, by a detailed analysis of the technical and conceptual character of all the standard conditions used in physics today, including examination of their consequences and the circumstances in which they are believed to be violated.

  18. Columbia University flow instability experimental program: Volume 6. Single annulus tests, transient test program

    SciTech Connect (OSTI)

    Dougherty, T.; Maciuca, C.; McAssey, E.V. Jr.; Reddy, D.G.; Yang, B.W.

    1992-09-01T23:59:59.000Z

    The coolant in the Savannah River Site (SRS) production nuclear reactor assemblies is circulated as a subcooled liquid under normal operating conditions. This coolant is evenly distributed throughout multiple annular flow channels with a uniform pressure profile across each coolant flow channel. During the postulated Loss of Coolant Accident (LOCA), which is initiated by a hypothetical guillotine pipe break, the coolant flow through the reactor assemblies is significantly reduced. The flow reduction and accompanying power reduction (after shutdown is initiated) occur in the first 1 to 2 seconds of the LOCA. This portion of the LOCA is referred to as the Flow Instability phase. This report presents the experimental results for the transient portion of the single annulus test program. The test program was designed to investigate the onset of flow instability in an annular geometry similar to the MARK 22 reactor. The test program involved testing of both a ribless heater and a ribbed heater under steady state as well as transient conditions. The ribbed heater testing is currently underway and will be reported separately. The steady state portion of this test program with ribless heater was completed and reported in report No. CU-HTRF-T3A. The present report presents transient test results obtained from a ribless, uniform annulus test section. A total of thirty five transients were conducted with six cases in which flow excursion occurred. No unstable conditions resulted for tests in which the steady state Q{sub ratio} OFI limit was not exceeded.

  19. Shear flow effects on ion thermal transport in tokamaks

    SciTech Connect (OSTI)

    Tajima, T.; Horton, W.; Dong, J.Q. [Univ. of Texas, Austin, TX (United States). Institute for Fusion Studies; Kishimoto, Y. [JAERI (Japan). Naka Fusion Research

    1995-03-01T23:59:59.000Z

    From various laboratory and numerical experiments, there is clear evidence that under certain conditions the presence of sheared flows in a tokamak plasma can significantly reduce the ion thermal transport. In the presence of plasma fluctuations driven by the ion temperature gradient, the flows of energy and momentum parallel and perpendicular to the magnetic field are coupled with each other. This coupling manifests itself as significant off-diagonal coupling coefficients that give rise to new terms for anomalous transport. The authors derive from the gyrokinetic equation a set of velocity moment equations that describe the interaction among plasma turbulent fluctuations, the temperature gradient, the toroidal velocity shear, and the poloidal flow in a tokamak plasma. Four coupled equations for the amplitudes of the state variables radially extended over the transport region by toroidicity induced coupling are derived. The equations show bifurcations from the low confinement mode without sheared flows to high confinement mode with substantially reduced transport due to strong shear flows. Also discussed is the reduced version with three state variables. In the presence of sheared flows, the radially extended coupled toroidal modes driven by the ion temperature gradient disintegrate into smaller, less elongated vortices. Such a transition to smaller spatial correlation lengths changes the transport from Bohm-like to gyrobohm-like. The properties of these equations are analyzed. The conditions for the improved confined regime are obtained as a function of the momentum-energy deposition rates and profiles. The appearance of a transport barrier is a consequence of the present theory.

  20. Ceramic Cross Flow Recuperator Design Parameters

    E-Print Network [OSTI]

    Gonzalez, J. M.; Rebello, W. J.

    1981-01-01T23:59:59.000Z

    the performance of the ceramic recuperator in various industrial furnaces. The ceramic cross flow recuperator core has multiple rectangular flow passages (perpendicular to each other) for the air and gas. Various flow passages are available contingent upon...

  1. Two phase flow in capillary tubes

    E-Print Network [OSTI]

    Suo, Mikio

    1963-01-01T23:59:59.000Z

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

  2. Insertable fluid flow passage bridgepiece and method

    DOE Patents [OSTI]

    Jones, Daniel O. (Glenville, NV)

    2000-01-01T23:59:59.000Z

    A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.

  3. Collective Dynamics of Interacting Particles in Unsteady Flows

    E-Print Network [OSTI]

    Abedi, Maryam

    2014-01-01T23:59:59.000Z

    We use the Fokker-Planck equation and its moment equations to study the collective behavior of interacting particles in unsteady one-dimensional flows. Particles interact according to a long-range attractive and a short-range repulsive potential field known as Morse potential. We assume Stokesian drag force between particles and their carrier fluid, and find analytic single-peaked traveling solutions for the spatial density of particles in the catastrophic phase. In steady flow conditions the streaming velocity of particles is identical to their carrier fluid, but we show that particle streaming is asynchronous with an unsteady carrier fluid. Using linear perturbation analysis, the stability of traveling solutions is investigated in unsteady conditions. It is shown that the resulting dispersion relation is an integral equation of the Fredholm type, and yields two general families of stable modes: singular modes whose eigenvalues form a continuous spectrum, and a finite number of discrete global modes. Dependi...

  4. Hanford Tank Farms Waste Certification Flow Loop Test Plan

    SciTech Connect (OSTI)

    Bamberger, Judith A.; Meyer, Perry A.; Scott, Paul A.; Adkins, Harold E.; Wells, Beric E.; Blanchard, Jeremy; Denslow, Kayte M.; Greenwood, Margaret S.; Morgen, Gerald P.; Burns, Carolyn A.; Bontha, Jagannadha R.

    2010-01-01T23:59:59.000Z

    A future requirement of Hanford Tank Farm operations will involve transfer of wastes from double shell tanks to the Waste Treatment Plant. As the U.S. Department of Energy contractor for Tank Farm Operations, Washington River Protection Solutions anticipates the need to certify that waste transfers comply with contractual requirements. This test plan describes the approach for evaluating several instruments that have potential to detect the onset of flow stratification and critical suspension velocity. The testing will be conducted in an existing pipe loop in Pacific Northwest National Laboratory’s facility that is being modified to accommodate the testing of instruments over a range of simulated waste properties and flow conditions. The testing phases, test matrix and types of simulants needed and the range of testing conditions required to evaluate the instruments are described

  5. From invasion percolation to flow in rock fracture networks

    E-Print Network [OSTI]

    Wettstein, Salomon J; Araujo, Nuno A M; Lanyon, Bill; Herrmann, Hans J

    2011-01-01T23:59:59.000Z

    The main purpose of this work is to simulate two-phase flow in the form of immiscible displacement through anisotropic, three-dimensional (3D) discrete fracture networks (DFN). The considered DFNs are artificially generated, based on a general distribution function or are conditioned on measured data from deep geological investigations. We introduce several modifications to the invasion percolation (MIP) to incorporate fracture inclinations, intersection lines, as well as the hydraulic path length inside the fractures. Additionally a trapping algorithm is implemented that forbids any advance of the invading fluid into a region, where the defending fluid is completely encircled by the invader and has no escape route. We study invasion, saturation, and flow through artificial fracture networks, with varying anisotropy and size and finally compare our findings to well studied, conditioned fracture networks.

  6. Flow distribution channels to control flow in process channels

    DOE Patents [OSTI]

    Tonkovich, Anna Lee; Arora, Ravi; Kilanowski, David

    2014-10-28T23:59:59.000Z

    The invention describes features that can be used to control flow to an array of microchannels. The invention also describes methods in which a process stream is distributed to plural microchannels.

  7. The transition from two phase bubble flow to slug flow

    E-Print Network [OSTI]

    Radovcich, Nick A.

    1962-01-01T23:59:59.000Z

    The process of transition from bubble to slug flow in a vertical pipe has been studied analytically and experimentally. An equation is presented which gives the agglomeration time as a function of void fraction, channel ...

  8. Parametric effects of glass reaction under unsaturated conditions

    SciTech Connect (OSTI)

    Bates, J.K.; Gerding, T.J.; Woodland, A.B.

    1989-11-01T23:59:59.000Z

    Eventual liquid water contact of high-level waste glass stored under the unsaturated conditions anticipated at the Yucca Mountain site will be by slow intrusion of water into a breached container/canister assembly. The water flow patterns under these unsaturated conditions will vary, and the Unsaturated Test method has been developed by the YMP to study glass reaction. The results from seven different sets of tests done to investigate the effect of systematically varying parameters, such as glass composition, composition and degree of sensitization of 304L stainless steel, water input volume, and the interval of water contact are discussed. Glass reaction has been monitored over a period of five years, and the parametric effects can result in up to a ten-fold variance in the degree of glass reaction.

  9. Thermocapillary Flow on Superhydrophobic Surfaces

    E-Print Network [OSTI]

    Baier, Tobias; Hardt, Steffen

    2010-01-01T23:59:59.000Z

    A liquid in Cassie-Baxter state above a structured superhydrophobic surface is ideally suited for surface driven transport due to its large free surface fraction in close contact to a solid. We investigate thermal Marangoni flow over a superhydrophobic array of fins oriented parallel or perpendicular to an applied temperature gradient. In the Stokes limit we derive an analytical expression for the bulk flow velocity above the surface and compare it with numerical solutions of the Navier-Stokes equation. Even for moderate temperature gradients comparatively large flow velocities are induced, suggesting to utilize this principle for microfluidic pumping.

  10. Macro-to-microchannel transition in two-phase flow: Part 1 - Two-phase flow patterns and film thickness measurements

    SciTech Connect (OSTI)

    Ong, C.L.; Thome, J.R. [Ecole Polytechnique Federale de Lausanne, EPFL-STI-IGM-LTCM, Station 9, CH-1015 Lausanne (Switzerland)

    2011-01-15T23:59:59.000Z

    The classification of macroscale, mesoscale and microscale channels with respect to two-phase processes is still an open question. The main objective of this study focuses on investigating the macro-to-microscale transition during flow boiling in small scale channels of three different sizes with three different refrigerants over a range of saturation conditions to investigate the effects of channel confinement on two-phase flow patterns and liquid film stratification in a single circular horizontal channel (Part 2 covers the flow boiling heat transfer and critical heat flux). This paper presents the experimental two-phase flow pattern transition data together with a top/bottom liquid film thickness comparison for refrigerants R134a, R236fa and R245fa during flow boiling in small channels of 1.03, 2.20 and 3.04 mm diameter. Based on this work, an improved flow pattern map has been proposed by determining the flow patterns transitions existing under different conditions including the transition to macroscale slug/plug flow at a confinement number of Co {approx} 0.3-0.4. From the top/bottom liquid film thickness comparison results, it was observed that the gravity forces are fully suppressed and overcome by the surface tension and shear forces when the confinement number approaches 1, Co {approx} 1. Thus, as a new approximate rule, the lower threshold of macroscale flow is Co = 0.3-0.4 while the upper threshold of symmetric microscale flow is Co {approx} 1 with a transition (or mesoscale) region in-between. (author)

  11. Admissibility Conditions for Degenerate Cyclotomic BMW Algebras

    E-Print Network [OSTI]

    Goodman, Frederick M

    2009-01-01T23:59:59.000Z

    We study admissibility conditions for the parameters of degenerate cyclotomic BMW algebras. We show that the u-admissibility condition of Ariki, Mathas and Rui is equivalent to a simple module theoretic condition.

  12. Flow-Through Microfluidic Device for High-Efficiency Transfection of Mammalian Cells through Combined Microelectroporation and Sonoporation

    E-Print Network [OSTI]

    Longsine, Whitney Leigh

    2012-07-16T23:59:59.000Z

    In this study we are presenting a proof-of-concept microfluidic device that simultaneously applies the conditions required for microelectroporation and micro-sonoporation in a flow-through fashion that allows for high throughput, high efficiency...

  13. An assessment of stream flow and habitat quality for steelhead trout in San Pablo Creek, Contra Costa County

    E-Print Network [OSTI]

    Anderson, Shannah; Maldague, Lorraine

    2004-01-01T23:59:59.000Z

    conditions in lower hayfork creek. http://www.krisweb.com/Comparison of Peak Flow Values Creek Name Method U s e d ton i n g Equation Wildcat Creek Unit Runoff Index Q2=31.05cfs

  14. Design and construction of an experiment for two-phase flow in fractured porous media

    SciTech Connect (OSTI)

    Ayala, R.E.G.; Aziz, K.

    1993-08-01T23:59:59.000Z

    In numerical reservoir simulation naturally fractured reservoirs are commonly divided into matrix and fracture systems. The high permeability fractures are usually entirely responsible for flow between blocks and flow to the wells. The flow in these fractures is modeled using Darcy`s law and its extension to multiphase flow by means of relative permeabilities. The influence and measurement of fracture relative permeability for two-phase flow in fractured porous media have not been studied extensively, and the few works presented in the literature are contradictory. Experimental and numerical work on two-phase flow in fractured porous media has been initiated. An apparatus for monitoring this type of flow was designed and constructed. It consists of an artificially fractured core inside an epoxy core holder, detailed pressure and effluent monitoring, saturation measurements by means of a CT-scanner and a computerized data acquisition system. The complete apparatus was assembled and tested at conditions similar to the conditions expected for the two-phase flow experiments. Fine grid simulations of the experimental setup-were performed in order to establish experimental conditions and to study the effects of several key variables. These variables include fracture relative permeability and fracture capillary pressure. The numerical computations show that the flow is dominated by capillary imbibition, and that fracture relative permeabilities have only a minor influence. High oil recoveries without water production are achieved due to effective water imbibition from the fracture to the matrix. When imbibition is absent, fracture relative permeabilities affect the flow behavior at early production times.

  15. Spectral functionals, nonholonomic Dirac operators, and noncommutative Ricci flows

    SciTech Connect (OSTI)

    Vacaru, Sergiu I. [Science Department, University 'Al. I. Cuza' Iasi, 54. Lascar Catargi street, Iasi, 700107 (Romania) and Fields Institute for Research in Mathematical Science, 222 College Street, 2nd Floor, Toronto M5T 3J1 (Canada)

    2009-07-15T23:59:59.000Z

    We formulate a noncommutative generalization of the Ricci flow theory in the framework of spectral action approach to noncommutative geometry. Grisha Perelman's functionals are generated as commutative versions of certain spectral functionals defined by nonholonomic Dirac operators and corresponding spectral triples. We derive the formulas for spectral averaged energy and entropy functionals and state the conditions when such values describe (non)holonomic Riemannian configurations.

  16. Lyapunov stability of flowing magnetohydrodynamic plasmas surrounded by resistive walls

    SciTech Connect (OSTI)

    Tasso, H. [Max-Planck-Institut fuer Plasmaphysik, Euratom Association, 85748 Garching (Germany); Throumoulopoulos, G. N. [Association Euratom-Hellenic Republic, Department of Physics, University of Ioannina, GR 451 10 Ioannina (Greece)

    2011-07-15T23:59:59.000Z

    A general stability condition for plasma-vacuum systems with resistive walls is derived by using the Frieman Rotenberg Lagrangian stability formulation [Rev. Mod. Phys. 32, 898 (1960)]. It is shown that the Lyapunov stability limit for external modes does not depend upon the gyroscopic term but upon the sign of the perturbed potential energy only. In the absence of dissipation in the plasma such as viscosity, it is expected that the flow cannot stabilize the system.

  17. Nuclear reactor flow control method and apparatus

    DOE Patents [OSTI]

    Church, John P. (1204 Woodbine Rd., Aiken, SC 29803)

    1993-01-01T23:59:59.000Z

    Method and apparatus for improving coolant flow in a nuclear reactor during accident as well as nominal conditions. The reactor has a plurality of fuel elements in sleeves and a plenum above the fuel and through which the sleeves penetrate. Holes are provided in the sleeve so that coolant from the plenum can enter the sleeve and cool the fuel. The number and size of the holes are varied from sleeve to sleeve with the number and size of holes being greater for sleeves toward the center of the core and less for sleeves toward the periphery of the core. Preferably the holes are all the same diameter and arranged in rows and columns, the rows starting from the bottom of every sleeve and fewer rows in peripheral sleeves and more rows in the central sleeves.

  18. Nuclear reactor flow control method and apparatus

    DOE Patents [OSTI]

    Church, J.P.

    1993-03-30T23:59:59.000Z

    Method and apparatus for improving coolant flow in a nuclear reactor during accident as well as nominal conditions. The reactor has a plurality of fuel elements in sleeves and a plenum above the fuel and through which the sleeves penetrate. Holes are provided in the sleeve so that coolant from the plenum can enter the sleeve and cool the fuel. The number and size of the holes are varied from sleeve to sleeve with the number and size of holes being greater for sleeves toward the center of the core and less for sleeves toward the periphery of the core. Preferably the holes are all the same diameter and arranged in rows and columns, the rows starting from the bottom of every sleeve and fewer rows in peripheral sleeves and more rows in the central sleeves.

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

    E-Print Network [OSTI]

    Shen, Bin; Zheng, Qiuhua

    2015-01-01T23:59:59.000Z

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

  20. Colorado: Isothermal Battery Calorimeter Quantifies Heat Flow...

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

    Isothermal Battery Calorimeter Quantifies Heat Flow, Helps Make Safer, Longer-lasting Batteries Colorado: Isothermal Battery Calorimeter Quantifies Heat Flow, Helps Make Safer,...

  1. Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling...

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

    Nozzle Flow, Spray, Combustion, & Emission Modeling using KH-ACT Primary Breakup Model & Detailed Chemistry Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling using...

  2. Automation of radiochemical analysis by applying flow

    E-Print Network [OSTI]

    Sánchez, David

    of detection systems, including scintillation counting, a-spectrometers, proportional counters, mass spectrometry and spectrophotometry. Ş 2010 Published by Elsevier Ltd. Keywords: Flow-analysis technique; Flow

  3. Integrated Simulations for Multi-Component Analysis of Gas Turbines : RANS Boundary Conditions

    E-Print Network [OSTI]

    Kim, Sangho

    More recently the coupling method has also been applied to a Pratt & Whitney gas turbine.7 The RANSIntegrated Simulations for Multi-Component Analysis of Gas Turbines : RANS Boundary Conditions 94305, U.S.A The aero-thermal computation of the flow path of an entire gas turbine engine can

  4. Start-Up of Air Conditioning Systems After Periods of Shutdown (Humidity Considerations)

    E-Print Network [OSTI]

    Todd, T. R.

    1986-01-01T23:59:59.000Z

    after the system is restarted. Moe t simply, condensation takes place when moist air flows past surfaces which have been cooled below its dewpoint. In air conditioning this occurs when the cold supply air being deli- vered into the space induces...

  5. Geometry of Power Flows in Tree Networks

    E-Print Network [OSTI]

    Lavaei, Javad; Zhang, Baosen

    2012-01-01T23:59:59.000Z

    We investigate the problem of power flow and its relationship to optimization in tree networks by looking at the injection regions of the networks. The injection region is the set of all vectors of bus power injections that satisfy the network and operation constraints. The geometrical object of interest is the set of Pareto-optimal points of the injection region, since they are the solutions to the minimization of increasing functions. If the voltage magnitudes are fixed, the injection region of a tree network can be written as a linear transformation of the product of two-bus injection regions, one for each line in the network. Using this decomposition, we show that under the practical condition that the angle difference across each line is not too large, the set of Pareto-optimal points of the injection region remains unchanged by taking the convex hull. Therefore, the optimal power flow problem can be convexified and efficiently solved. This result improves upon earlier works by removing the assumptions o...

  6. A Performance Comparison of Condition Based Monitoring Damage Features Used in Rotating Machines under Variable Conditions /

    E-Print Network [OSTI]

    Robinson, Luke Thomas

    2013-01-01T23:59:59.000Z

    and M. Papaelias, “Condition monitoring of wind turbines:Condition monitoring and fault detection of wind turbinesCondition monitoring and fault diagnostics of wind turbines,”

  7. A one-way coupled, EulerLagrangian simulation of bubble coalescence in a turbulent pipe flow

    E-Print Network [OSTI]

    Mahesh, Krishnan

    modifies the speed of sound in the bubbly mixture, which has implications for marine acoustic signatures. Gas­liquid flow at microgravity conditions ­ I. Dispersed bubble and slug flow. Int. J. Multiphase- ical in many heat transfer problems where liquid water contacting a hot surface boils and the resulting

  8. O Isotopic Composition of CaCO3 Measured by Continuous Flow Isotope Ratio Mass Spectrometry: Statistical Evaluation and

    E-Print Network [OSTI]

    d13 C and d18 O Isotopic Composition of CaCO3 Measured by Continuous Flow Isotope Ratio Mass method streamlines the classical phosphoric acid ­ calcium carbonate (H3 PO4 ­ CaCO3 ) reaction method XL continuous flow isotope ratio mass spectrometer. Conditions for which the H3 PO4 ­ CaCO3 reaction

  9. A posteriori error estimates with application of adaptive mesh refinement for thermal multiphase compositional flows in porous

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of diffusive fluxes. Numerical results on an example of real-life thermal oil-recovery in a reservoir refinement, compositional Darcy flow, thermal flow, finite volume method 1 Introduction The thermal under a non-isothermal condition. The governing equations are the conservation of the amount of each

  10. Letter Report: Borehole Flow and Horizontal Hydraulic Conductivity with Depth at Well ER-12-3

    SciTech Connect (OSTI)

    P. Oberlander; C. Russell

    2005-09-01T23:59:59.000Z

    Borehole flow and fluid temperature during pumping were measured at well ER-12-3 at the Nevada Test Site in Nye County, Nevada. This well was constructed to characterize the carbonate aquifer. The well is cased from land surface to the total depth at 1,487 m (4,880 ft) below ground surface (bgs). Slotted screen is placed in an upper screened section from 1,095 to 1,160 m bgs (3,591 to 3,805 ft bgs) and in the lower screened section from 1,278 to 1,474 m bgs (4,191 to 4,834 ft bgs). Borehole flow velocity (LT-1) with depth was measured with an impeller flowmeter from the top of the screened section to the maximum accessible depth while the well was pumped and under ambient conditions. A complicating factor to data interpretation is that the well was not filter packed and there is significant upward and downward vertical flow in the open annulus under ambient and pumping conditions. The open annulus and large vertical flow velocities in the well casing result in the measured borehole flow rates being potentially highly nonrepresentative of conditions in the aquifer. Hydraulic conductivities calculated under these conditions would require unsupportable assumptions and would be subject to very large uncertainties. Borehole hydraulic conductivities are not presented under these conditions.

  11. Building America Webinar: High Performance Space Conditioning...

    Energy Savers [EERE]

    Webinar: High Performance Space Conditioning Systems, Part II - Compact Buried Ducts Building America Webinar: High Performance Space Conditioning Systems, Part II - Compact Buried...

  12. Space Conditioning Standing Technical Commitee Presentation ...

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

    Commitee Presentation Space Conditioning Standing Technical Commitee Presentation This presentation outlines the goals of the Space Conditioning Standing Technical ommittee, as...

  13. Building America Webinar: High Performance Space Conditioning...

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

    II - Design Options for Locating Ducts within Conditioned Space Building America Webinar: High Performance Space Conditioning Systems, Part II - Design Options for Locating Ducts...

  14. Lab Breakthrough: Desiccant Enhanced Evaporative Air Conditioning...

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

    Desiccant Enhanced Evaporative Air Conditioning Lab Breakthrough: Desiccant Enhanced Evaporative Air Conditioning May 29, 2012 - 5:22pm Addthis This breakthrough combines desiccant...

  15. Viscous Flows and Conditions for Existence of Shocks in Relativistic Magnetic Hydrodynamics

    E-Print Network [OSTI]

    V. I. Zhdanov; P. V. Tytarenko; M. S. Borshch

    2004-07-23T23:59:59.000Z

    We present a criterion for a shock wave existence in relativistic magnetic hydrodynamics with an arbitrary (possibly non-convex) equation of state. The criterion has the form of algebraic inequality that involves equation of state of the fluid; it singles out the physical solutions and it can be easily checked for any discontinuity satisfying concervation laws. The method of proof uses introduction of small viscosity into the coupled set of equations of motion of ideal relativistic fluid with infinite conductivity and Maxwell equations.

  16. Analysis of alternatives for computing backwater at bridges for free-surface, subcritical flow conditions

    E-Print Network [OSTI]

    Kaatz, Kelly Jay

    1993-01-01T23:59:59.000Z

    Downsville, Louisiana Profde Computation Results . . 46 Flagon Bayou near Libuse, Louisiana Site Characteristics . . . 51 Flagon Bayou near Libuse, Louisiana Profile Computation Results 52 Alexander Creek near St. Francisville, Louisiana Site... Characteristics . 56 Alexander Creek near St. Francisville, Louisiana Flood of September 17, 1971 Profile Computation Results . . . . . . . . . . . . . . . . . . 57 Tenmile Creek near Elizabeth, Louisiana Site Characteristics . 62 10 Tenmile Creek near...

  17. The rapid synthesis of oxazolines and their heterogeneous oxidation to oxazoles under flow conditions

    E-Print Network [OSTI]

    Glöckner, Steffen; Tran, Duc N.; Ingham, Richard J.; Fenner, Sabine; Wilson, Zoe E.; Battilocchio, Claudio; Ley, Steven V.

    2014-10-28T23:59:59.000Z

    . Microfluidics are known to provide a highly efficient static mixing23- 26 and therefore the cyclodehydration of ?-hydroxy amides 1b and 1i was attempted on a 1 µL (Labtrix Start) microchip (Scheme 2).27 It was found that both substrates could...

  18. Modeling of Multiphase Flow in the Near-Wellbore Region of the Reservoir under Transient Conditions

    E-Print Network [OSTI]

    Zhang, He

    2010-07-14T23:59:59.000Z

    to the RWE, PetroBras, and Shell US, which sponsored this work as part of the JIP project later of this study. Finally, thanks to my father, mother, and sister for their consistent encouragement and to my wife for her greatest support and love. vi... of this work. Finally it presents an overview of the Joint Industry Project (JIP) on ?Liquid Loading in the Operation of Gas Fields: Mechanisms, Prediction and Reservoir Response,? and explains the role of this work as part of the JIP?s objectives. Chapter...

  19. Attenuation of hydrogen radicals traveling under flowing gas conditions through tubes of different materials

    E-Print Network [OSTI]

    George, Steven M.

    efficiently on the exposed thermocouple and the energy of formation of H2 heated the thermocouple. The second thermocouple was covered by glass and was heated primarily by the ambient gas. The dual thermocouple probe or on a catalytic surface in contact with a thermocouple. The recombination energy heats the thermo- couple

  20. Vertical Flow Dynamics in Kelp Forests: Implications for Nutrient Uptake, Condition and Survival

    E-Print Network [OSTI]

    Edwards, Matthew S.

    2008-01-01T23:59:59.000Z

    Dynamics in Kelp Forests: Implications for Nutrient Uptake,on the temperature/nutrient regime around giant kelp will benutrient-rich water results in increased Nitrogen uptake by giant kelp and

  1. Estimation of Hydraulic Parameters under Unsaturated Flow Conditions in Heap Leaching

    E-Print Network [OSTI]

    Sepúlveda, Mauricio

    is a widely used extraction method for low-grade minerals as well as copper, gold, silver, and uranium. Copper minerals are primar- ily categorized as either copper sulphides or oxides. During heap leaching, sulfuric is suitable for copper recovery of the more stable sulphide minerals from copper ores. The construction

  2. Modeling of Multiphase Flow in the Near-Wellbore Region of the Reservoir under Transient Conditions 

    E-Print Network [OSTI]

    Zhang, He

    2010-07-14T23:59:59.000Z

    /ft ? porosity ? viscosity, cp ? angle, degree Subscripts c condensate g gas m neighboring gridblock to gridblock n n gridblock o oil r relative sg solution gas w water Superscripts n old timestep n+1 current timestep viii TABLE OF CONTENTS....2). The ?backpressure? (Eq. 2.11) is one of the most widely used inflow expressions for gas well. 9 n wfrG ppCq )( 2 2 ?= ??????.???????????????? (2.11) where C is the inflow coefficient, Mscf/(D-psi n ), and n is the inflow exponent in the range of 0.5 to 1...

  3. Spatial and temporal analysis and experiments of annular two-phase flow under microgravity conditions

    E-Print Network [OSTI]

    Carron, Igor

    1992-01-01T23:59:59.000Z

    of the coexistence of huge waves with liquid slugs. This last observation however is already too detailed for the codes that are developed nowadays for nuclear safety assessment such as RELAP 5 [6). One of the main issue is therefore to characterize quantitatively... and base state II. 5 Verification of the code II. 6 Implementation . . II. 7 Conclusion 17 18 20 30 34 40 45 EXPERIMENTS IN A REDI. CED GRAVITY ENVIRONMENT . . III. l Experiments carried out at Texas A@i%'I University III. 2 The 1986 experiment...

  4. Use of tritium and helium to define groundwater flow conditions in Everglades National Park

    E-Print Network [OSTI]

    Swart, Peter K.

    and tem- perature as tracers of the seawater intrusion into coastal aquifers [Back et al., 1970; Kohout

  5. Kinetics of Fe(II)-catalyzed transformation of 6-line ferrihydrite under anaerobic flow conditions

    E-Print Network [OSTI]

    Yang, L.

    2010-01-01T23:59:59.000Z

    transformation to goethite via the Fe(II) pathway. Am.ferrihydrite, and goethite. Geochim. Cosmochim. Acta 2001,between Aqueous Fe(II) and Goethite: An Fe Isotope Tracer

  6. Identification of the Flow Resistance Coefficient and Validation of a Building Air Conditioning System

    E-Print Network [OSTI]

    Hou, Z.; Lian, Z.

    2006-01-01T23:59:59.000Z

    The fundamental parameter that characterizes the hydraulic state of a water pipeline and largely determines the efficiency of the water-transport process is the hydraulic resistance coefficient (HRC). The actual values of the HRC may be different...

  7. An investigation of effects of flow conditioning on straight tube Coriolis meter

    E-Print Network [OSTI]

    Shukla, Shashank

    2009-05-15T23:59:59.000Z

    metering can be very beneficial for the following1, 2. 1.1.1 Layout of production facilities Use of multiphase meters reduces the hardware needed for onshore, offshore topside and offshore subsea applications by eliminating the need of dedicated test... Coriolis meters are essentially aeroelastic devices; and as such involve coupled dynamic interaction of fluid dynamics and structural system. The Coriolis meter basically consists of a tube conveying fluid (lying in one plane and clamped at its ends...

  8. Minimum Stream Flow Standards (Connecticut)

    Broader source: Energy.gov [DOE]

    These regulations apply to all dams and structures which impound or divert waters on rivers or their tributaries, with some exceptions. The regulations set standards for minimum flow (listed in the...

  9. Nodes, modes and flow codes

    SciTech Connect (OSTI)

    Karniadakis, G.E.; Orszag, S.A. (Princeton Univ., NJ (United States))

    1993-03-01T23:59:59.000Z

    Computational fluid dynamics and the numerical prediction of fluid flow in the understanding and modeling of turbulence is discussed with emphasis on the development of direct numerical simulation (DNS) of high-Reynolds number turbulent flows. Recent advances in computer systems and their use in turbulence simulation are reviewed and the need for parallel processing to achieve teraflop speeds necessary for DNS is discussed. Computer system architectures, nodes, and parallel computers currently in use are reviewed. Spectral, spectral-element, particle, and hybrid difference methods of solving incompressible- and compressible-flow problems are examined. Four applications of parallel computers to turbulent flow problems are presented and future developments in computer systems are discussed. 24 refs.

  10. Miniaturized flow injection analysis system

    DOE Patents [OSTI]

    Folta, James A. (Livermore, CA)

    1997-01-01T23:59:59.000Z

    A chemical analysis technique known as flow injection analysis, wherein small quantities of chemical reagents and sample are intermixed and reacted within a capillary flow system and the reaction products are detected optically, electrochemically, or by other means. A highly miniaturized version of a flow injection analysis system has been fabricated utilizing microfabrication techniques common to the microelectronics industry. The microflow system uses flow capillaries formed by etching microchannels in a silicon or glass wafer followed by bonding to another wafer, commercially available microvalves bonded directly to the microflow channels, and an optical absorption detector cell formed near the capillary outlet, with light being both delivered and collected with fiber optics. The microflow system is designed mainly for analysis of liquids and currently measures 38.times.25.times.3 mm, but can be designed for gas analysis and be substantially smaller in construction.

  11. Message Flow Modulator Final Report

    E-Print Network [OSTI]

    Boyer, Robert Stephen

    operational environment at the Patuxent River Naval Air Test Center with scenarios developed by an independent in testing and demonstrating the flow modulator at the Patuxent River Naval Air Test Center. #12; MESSAGE

  12. Capillary flows in flexible structures

    E-Print Network [OSTI]

    Hoberg, Theresa B. (Theresa Blinn)

    2013-01-01T23:59:59.000Z

    Interactions between capillary and elastic effects are relevant to a variety of applications, from micro- and nano-scale manufacturing to biological systems. In this thesis, we investigate capillary flows in extremely ...

  13. Mechanical design of flow batteries

    E-Print Network [OSTI]

    Hopkins, Brandon J. (Brandon James)

    2013-01-01T23:59:59.000Z

    The purpose of this research is to investigate the design of low-cost, high-efficiency flow batteries. Researchers are searching for next-generation battery materials, and this thesis presents a systems analysis encompassing ...

  14. 2007 Estimated International Energy Flows

    SciTech Connect (OSTI)

    Smith, C A; Belles, R D; Simon, A J

    2011-03-10T23:59:59.000Z

    An energy flow chart or 'atlas' for 136 countries has been constructed from data maintained by the International Energy Agency (IEA) and estimates of energy use patterns for the year 2007. Approximately 490 exajoules (460 quadrillion BTU) of primary energy are used in aggregate by these countries each year. While the basic structure of the energy system is consistent from country to country, patterns of resource use and consumption vary. Energy can be visualized as it flows from resources (i.e. coal, petroleum, natural gas) through transformations such as electricity generation to end uses (i.e. residential, commercial, industrial, transportation). These flow patterns are visualized in this atlas of 136 country-level energy flow charts.

  15. particle flow for nonlinear filters

    E-Print Network [OSTI]

    Dobigeon, Nicolas

    particle flow for nonlinear filters Fred Daum 19 June 2012 Copyright © 2012 Raytheon Company. All rights reserved. Customer Success Is Our Mission is a trademark of Raytheon Company. 1 #12;discrete time

  16. Multiscale modeling in granular flow

    E-Print Network [OSTI]

    Rycroft, Christopher Harley

    2007-01-01T23:59:59.000Z

    Granular materials are common in everyday experience, but have long-resisted a complete theoretical description. Here, we consider the regime of slow, dense granular flow, for which there is no general model, representing ...

  17. Field Flows of Dark Energy

    E-Print Network [OSTI]

    Cahn, Robert N.

    2010-01-01T23:59:59.000Z

    Field Flows of Dark Energy Robert N. Cahn, Roland de Putter,July 8, 2008) Scalar ?eld dark energy evolving from a longthe key aspects of the dark energy evolution during much of

  18. Longitudinal dispersion in vegetated flow

    E-Print Network [OSTI]

    Murphy, Enda

    2006-01-01T23:59:59.000Z

    Vegetation is ubiquitous in rivers, estuaries and wetlands, strongly influencing both water conveyance and mass transport. The plant canopy affects both mean and turbulent flow structure, and thus both advection and ...

  19. Subcooled flow boiling of fluorocarbons

    E-Print Network [OSTI]

    Murphy, Richard Walter

    1971-01-01T23:59:59.000Z

    A study was conducted of heat transfer and hydrodynamic behavior for subcooled flow boiling of Freon-113, one of a group of fluorocarbons suitable for use in cooling of high-power-density electronic components. Problems ...

  20. Modeling for Free Surface Flow with Phase Change

    SciTech Connect (OSTI)

    Luo Xiaoyong; Ni Mingjiu; Ying, Alice; Abdou, M. [University of California, Los Angeles (United States)

    2005-05-15T23:59:59.000Z

    The development of predictive capability for free surface flow with phase change is essential to evaluate liquid wall protection schemes for various fusion chambers in IFE and MFE. This paper presents a numerical methodology for free surface flow with heat and mass transfer to help resolve feasibility issues encountered in the aforementioned fusion engineering fields. The numerical methodology is conducted within the framework of the incompressible flow with the heat and mass transfer model. We present a new second-order projection method, in conjunction with Approximate-Factorization techniques (AF method) for incompressible Navier-Stokes equations. The level set method was used to capture the free surface of the flow and the deformation of the droplets accurately. This numerical investigation identifies the physics characterizing transient heat and mass transfer of the droplet and the free surface flow. The preliminary results show that the numerical methodology is successful in modeling the free surface with heat and mass transfer, though some severe deformation such as breaking and merging occurs. The versatility of the numerical methodology shows that the work can easily handle complex physical conditions in fusion science and engineering.

  1. Investigation of single-substance horizontal two-phase flow

    SciTech Connect (OSTI)

    Dickinson, D.A.; Maeder, P.F.

    1984-03-01T23:59:59.000Z

    Despite the abundance of work in the field of two-phase flow, it seems as though a consensus has not been reached on some of the fundamental points. Although exceptions exist, adequate physical interpretation of the flow seems to be hindered either by complexity of analysis or, in the opposite extreme, the trend toward limited-range analysis and correlations. The dissertation presents the derivation of basic conservation equations for the phases. The combined equations are used to examine the phenomenon of slip and its practical limitations, the Fanno line for single-substance flow and the effect of slip on choking. Equations for critical mass flux in the presence of slip are derived. The Mach, Reynolds and Froude numbers based on conditions at flashing are introduced as the characteristic parameters, and the importance of compressibility in single-substance two-phase flow is discussed. Experimental measurements of pressure change and void fraction for flow in the highly compressible range (.5 < Ma < 1) are presented. The working fluid is Refrigerant R-114, at room temperature, in a test section of diameter 5 cm and length 8 m. The effect of the Froude and Mach numbers is examined. The experimental facility is operated intermittently with running times of approximately two minutes and is instrumented for rapid measurements using a computer data acquisition and control system. A description of the facility and procedure is provided.

  2. AnalyzeHOLE: An Integrated Wellbore Flow Analysis Tool

    SciTech Connect (OSTI)

    Keith J. Halford

    2009-10-01T23:59:59.000Z

    Conventional interpretation of flow logs assumes that hydraulic conductivity is directly proportional to flow change with depth. However, well construction can significantly alter the expected relation between changes in fluid velocity and hydraulic conductivity. Strong hydraulic conductivity contrasts between lithologic intervals can be masked in continuously screened wells. Alternating intervals of screen and blank casing also can greatly complicate the relation between flow and hydraulic properties. More permeable units are not necessarily associated with rapid fluid-velocity increases. Thin, highly permeable units can be misinterpreted as thick and less permeable intervals or not identified at all. These conditions compromise standard flow-log interpretation because vertical flow fields are induced near the wellbore. AnalyzeHOLE, an integrated wellbore analysis tool for simulating flow and transport in wells and aquifer systems, provides a better alternative for simulating and evaluating complex well-aquifer system interaction. A pumping well and adjacent aquifer system are simulated with an axisymmetric, radial geometry in a two-dimensional MODFLOW model. Hydraulic conductivities are distributed by depth and estimated with PEST by minimizing squared differences between simulated and measured flows and drawdowns. Hydraulic conductivity can vary within a lithology but variance is limited with regularization. Transmissivity of the simulated system also can be constrained to estimates from single-well, pumping tests. Water-quality changes in the pumping well are simulated with simple mixing models between zones of differing water quality. These zones are differentiated by backtracking thousands of particles from the well screens with MODPATH. An Excel spreadsheet is used to interface the various components of AnalyzeHOLE by (1) creating model input files, (2) executing MODFLOW, MODPATH, PEST, and supporting FORTRAN routines, and (3) importing and graphically displaying pertinent results.

  3. EFFECT OF CLIMATE CHANGE ON WATERSHED RUNOFF FLOW - UPPER COOSA RIVER BASIN UPSTREAM FROM PLANT HAMMOND

    SciTech Connect (OSTI)

    Chen, K.

    2011-10-24T23:59:59.000Z

    The ability of water managers to maintain adequate supplies in the coming decades depends on future weather conditions, as climate change has the potential to reduce stream flows from their current values due to potentially less precipitation and higher temperatures, and possibly rendering them unable to meet demand. The upper Coosa River basin, located in northwest Georgia, plays an important role in supplying water for industry and domestic use in northern Georgia, and has been involved in water disputes in recent times. The seven-day ten-year low flow (7Q10 flow) is the lowest average flow for seven consecutive days that has an average recurrence interval of 10 years. The 7Q10 flow is statistically derived from the observed historical flow data, and represents the low flow (drought) condition for a basin. The upper Coosa River basin also supplies cooling water for the 935MW coal-fired Hammond plant, which draws about 65% of the 7Q10 flow of the upper Coosa River to dissipate waste heat. The water is drawn through once and returned to the river directly from the generator (i.e., no cooling tower is used). Record low flows in 2007 led to use of portable cooling towers to meet temperature limits. Disruption of the Plant Hammond operation may trigger closure of area industrial facilities (e.g. paper mill). The population in Georgia is expected to double from 9 million to 18 million residents in the next 25 years, mostly in the metropolitan Atlanta area. Therefore, there will be an even greater demand for potable water and for waste assimilation. Climate change in the form of persistent droughts (causing low flows) and high ambient temperatures create regulatory compliance challenges for Plant Hammond operating with a once-through cooling system. Therefore, the Upper Coosa River basin was selected to study the effect of potential future weather change on the watershed runoff flow.

  4. An evaluation of pressure and flow measurement in the Molten Salt Test Loop (MSTL) system.

    SciTech Connect (OSTI)

    Gill, David Dennis; Kolb, William J.; Briggs, Ronald J.

    2013-07-01T23:59:59.000Z

    The National Solar Thermal Test Facility at Sandia National Laboratories has a unique test capability called the Molten Salt Test Loop (MSTL) system. MSTL allows customers and researchers to test components in flowing, molten nitrate salt at plant-like conditions for pressure, flow, and temperature. An important need in thermal storage systems that utilize molten salts is for accurate flow and pressure measurement at temperatures above 535%C2%B0C. Currently available flow and pressure instrumentation for molten salt is limited to 535%C2%B0C and even at this temperature the pressure measurement appears to have significant variability. It is the design practice in current Concentrating Solar Power plants to measure flow and pressure on the cold side of the process or in dead-legs where the salt can cool, but this practice won't be possible for high temperature salt systems. For this effort, a set of tests was conducted to evaluate the use of the pressure sensors for flow measurement across a device of known flow coefficient Cv. To perform this task, the pressure sensors performance was evaluated and was found to be lacking. The pressure indicators are severely affected by ambient conditions and were indicating pressure changes of nearly 200psi when there was no flow or pressure in the system. Several iterations of performance improvement were undertaken and the pressure changes were reduced to less than 15psi. The results of these pressure improvements were then tested for use as flow measurement. It was found that even with improved pressure sensors, this is not a reliable method of flow measurement. The need for improved flow and pressure measurement at high temperatures remains and will need to be solved before it will be possible to move to high temperature thermal storage systems with molten salts.

  5. Hot conditioning equipment conceptual design report

    SciTech Connect (OSTI)

    Bradshaw, F.W., Westinghouse Hanford

    1996-08-06T23:59:59.000Z

    This report documents the conceptual design of the Hot Conditioning System Equipment. The Hot conditioning System will consist of two separate designs: the Hot Conditioning System Equipment; and the Hot Conditioning System Annex. The Hot Conditioning System Equipment Design includes the equipment such as ovens, vacuum pumps, inert gas delivery systems, etc.necessary to condition spent nuclear fuel currently in storage in the K Basins of the Hanford Site. The Hot Conditioning System Annex consists of the facility of house the Hot Conditioning System. The Hot Conditioning System will be housed in an annex to the Canister Storage Building. The Hot Conditioning System will consist of pits in the floor which contain ovens in which the spent nuclear will be conditioned prior to interim storage.

  6. Application of a Hydrodynamic Model for Assessing the Hydraulic Capacity and Flow Field at Willamette Falls Dam, Oregon

    SciTech Connect (OSTI)

    Lee, Cheegwan; Yang, Zhaoqing; Khangaonkar, Tarang P.; Divers, Arya-Behbehani

    2006-08-03T23:59:59.000Z

    The Willamette Falls Hydroelectric Power Dam, operated by Portland General Electric (PGE), is located on the Willamette River, Oregon. The Project site consists of T.W. Sullivan Power Plant and a 2,950-ft-long spillway located on the top of the Willamette Falls Dam. As part of the effort of protection and enhancement of environmental resources, a flow control structure at the dam was proposed to improve the flow field and enhance the downstream juvenile fish passage in the region just upstream of the forebay (pre-forebay). The flow in the pre-forebay of Willamette Falls Dam is affected by the complex geometry and bathymetry, powerhouse flow, fish ladder flow and the spillway around the dam. The expectation was that the flow would be sensitive to the proposed flow control structures and could be modified to enhance downstream migration. In this study, a three-dimensional, free-surface hydrodynamic model (EFDC) was developed for the pre-forebay region of Willamette Falls to evaluate the feasibility of the proposed alternative and its effect on the flow field in two different flow regimes (low and high river flow), as well as to assess the hydraulic capacity of flow control structures. One of the key challenges in this modeling study was to properly specify the free open boundary conditions along the 2,950-feet-long spillway. In this study, a pressure boundary condition based on hydraulic head rating curves was applied to the free spillway boundary. The numerical model was calibrated with ADP velocity measurements at 17 stations for the existing low flow condition. Good agreements between model results and measured data were obtained, indicating the successful application of pressure boundary condition on the free spillway boundary. The calibrated model was applied to simulate the flow field and free surface elevation in the high flow region near the control flow structures under different alternative conditions. The model results were used to evaluate the effectiveness of flow control structure alternative for downstream fish passage. The model was also used to estimate the hydraulic capacity based on the water surface head drops upstream of the structures. This model application demonstrated that a free surface coastal model can be used successfully to examine free surface hydraulic problems near high velocity regions upstream of spillways at dams.

  7. Wind Turbine Drivetrain Condition Monitoring (Presentation)

    SciTech Connect (OSTI)

    Sheng, S.

    2011-10-01T23:59:59.000Z

    This presentation details the Gearbox Reliability Collaborative Condition Monitoring program at NREL.

  8. Thermophysical property-related comparison criteria for nanofluid heat transfer enhancement in turbulent flow.

    SciTech Connect (OSTI)

    Yu, W.; France, D. M.; Timofeeva, E. V.; Singh, D.; Routbort, J. L. (Energy Systems); ( NE)

    2010-01-01T23:59:59.000Z

    Heat transfer enhancement criteria for nanofluids over their base fluids are presented based on three separate considerations: Reynolds number, flow velocity, and pumping power. Analyses presented show that, among the three comparisons, the constant pumping power comparison is the most unambiguous; the constant flow velocity comparison can be quite reasonable under certain conditions but the constant Reynolds number comparison (the most commonly used in the engineering literature for nanofluids) distorts the physical situation, and therefore, should not be used

  9. Two-phase flow interfacial drag for once through steam generators

    E-Print Network [OSTI]

    Rais, Omar Tahar

    1990-01-01T23:59:59.000Z

    to be the best available for rod bundle geometries ' ": * Bestion drift flux model'4 * Electrical Power Research Institute (EPRI) drift flux model is 29 The definitions used in the EPRI correlation involve more complex functions of flow properties.... The EPRI correlation has been validated over a much wider range of conditions than the Bestion correlation principally because its drift flux parameters depend on more flow variables9, and therefore was adopted for the purpose of this project. Overall...

  10. Integration of geodesic flows on homogeneous spaces: the case of a wild lie group

    E-Print Network [OSTI]

    A. A. Magazev; I. V. Shirokov

    2007-03-21T23:59:59.000Z

    We obtain necessary and sufficient conditions for the integrability in quadratures of geodesic flows on homogeneous spaces $M$ with invariant and central metrics. The proposed integration algorithm consists in using a special canonical transformation in the space $T^*M$ based on constructing the canonical coordinates on the orbits of the coadjoint representation and on the simplectic sheets of the Poisson algebra of invariant functions. This algorithm is applicable to integrating geodesic flows on homogeneous spaces of a wild Lie group.

  11. RESEARCH ARTICLE Effectiveness of pulse flows in a regulated river for inducing

    E-Print Network [OSTI]

    Hinch, Scott G.

    ) in a reach of the Puntledge River where water is diverted for power generation, resulting in stable low flows (i.e., turbine out flows), and/or the presence of non-optimal environmental conditions (i.e., cold, Courtenay, BC V9N 2Z5, Canada B. Mossop BC Hydro, 6911 Southpoint Drive, Burnaby, BC V3N 4X8, Canada S. G

  12. ACHIEVING THE REQUIRED COOLANT FLOW DISTRIBUTION FOR THE ACCELERATOR PRODUCTION OF TRITIUM (APT) TUNGSTEN NEUTRON SOURCE

    SciTech Connect (OSTI)

    D. SIEBE; K. PASAMEHMETOGLU

    2000-11-01T23:59:59.000Z

    The Accelerator Production of Tritium neutron source consists of clad tungsten targets, which are concentric cylinders with a center rod. These targets are arranged in a matrix of tubes, producing a large number of parallel coolant paths. The coolant flow required to meet thermal-hydraulic design criteria varies with location. This paper describes the work performed to ensure an adequate coolant flow for each target for normal operation and residual heat-removal conditions.

  13. The low temperature differential Stirling engine with working fluid operated on critical condition

    SciTech Connect (OSTI)

    Naso, V.; Dong, W.; Lucentini, M.; Capata, R.

    1998-07-01T23:59:59.000Z

    The research and development of low temperature differential Stirling engine has a great potential market since a lot of thermal energy at low temperature can supply it and the cost of this kind of engine is lower than general Stirling engine. The characteristics of low compression ratio and low differential temperature Stirling engine may be satisfied with working fluid compressed on critical conditions. By combining two phase heat transfer with forced convective flow in compression space and through the regenerator in the engine, a new heat transfer coefficient emerges capable of absorbing and releasing high heat fluxes without the corresponding low temperature increase. The current analysis focuses on the study of Stirling engines with working fluid compressed on critical conditions, thus at two-phase heat transfer in compression space and regenerator of the engine under forced convective flow conditions.

  14. Flow Duration Curve Load Duration Curve

    E-Print Network [OSTI]

    Flow Duration Curve Load Duration Curve 1. Develop Flow Duration Curve 2. Estimate load given flow and concentration data--select appropriate conversion factors 3. Develop Load Duration Curve 4. Plot observed data with Load Duration Curve What are they? How do you make one? Describes the percent of time a flow rate

  15. Stochastic models for turbulent reacting flows

    SciTech Connect (OSTI)

    Kerstein, A. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01T23:59:59.000Z

    The goal of this program is to develop and apply stochastic models of various processes occurring within turbulent reacting flows in order to identify the fundamental mechanisms governing these flows, to support experimental studies of these flows, and to further the development of comprehensive turbulent reacting flow models.

  16. Advanced tomographic flow diagnostics for opaque multiphase fluids

    SciTech Connect (OSTI)

    Torczynski, J.R.; O`Hern, T.J.; Adkins, D.R.; Jackson, N.B.; Shollenberger, K.A.

    1997-05-01T23:59:59.000Z

    This report documents the work performed for the ``Advanced Tomographic Flow Diagnostics for Opaque Multiphase Fluids`` LDRD (Laboratory-Directed Research and Development) project and is presented as the fulfillment of the LDRD reporting requirement. Dispersed multiphase flows, particularly gas-liquid flows, are industrially important to the chemical and applied-energy industries, where bubble-column reactors are employed for chemical synthesis and waste treatment. Due to the large range of length scales (10{sup {minus}6}-10{sup 1}m) inherent in real systems, direct numerical simulation is not possible at present, so computational simulations are forced to use models of subgrid-scale processes, the accuracy of which strongly impacts simulation fidelity. The development and validation of such subgrid-scale models requires data sets at representative conditions. The ideal measurement techniques would provide spatially and temporally resolved full-field measurements of the distributions of all phases, their velocity fields, and additional associated quantities such as pressure and temperature. No technique or set of techniques is known that satisfies this requirement. In this study, efforts are focused on characterizing the spatial distribution of the phases in two-phase gas-liquid flow and in three-phase gas-liquid-solid flow. Due to its industrial importance, the bubble-column geometry is selected for diagnostics development and assessment. Two bubble-column testbeds are utilized: one at laboratory scale and one close to industrial scale. Several techniques for measuring the phase distributions at conditions of industrial interest are examined: level-rise measurements, differential-pressure measurements, bulk electrical impedance measurements, electrical bubble probes, x-ray tomography, gamma-densitometry tomography, and electrical impedance tomography.

  17. Free-surface flow simulations for discharge-based operation of hydraulic structure gates

    E-Print Network [OSTI]

    Erdbrink, C D; Sloot, P M A

    2014-01-01T23:59:59.000Z

    We combine non-hydrostatic flow simulations of the free surface with a discharge model based on elementary gate flow equations for decision support in operation of hydraulic structure gates. A water level-based gate control used in most of today's general practice does not take into account the fact that gate operation scenarios producing similar total discharged volumes and similar water levels may have different local flow characteristics. Accurate and timely prediction of local flow conditions around hydraulic gates is important for several aspects of structure management: ecology, scour, flow-induced gate vibrations and waterway navigation. The modelling approach is described and tested for a multi-gate sluice structure regulating discharge from a river to the sea. The number of opened gates is varied and the discharge is stabilized with automated control by varying gate openings. The free-surface model was validated for discharge showing a correlation coefficient of 0.994 compared to experimental data. A...

  18. Driven cavity flow: from molecular dynamics to continuum hydrodynamics

    E-Print Network [OSTI]

    Tiezheng Qian; Xiao-Ping Wang

    2004-03-06T23:59:59.000Z

    Molecular dynamics (MD) simulations have been carried out to investigate the slip of fluid in the lid driven cavity flow where the no-slip boundary condition causes unphysical stress divergence. The MD results not only show the existence of fluid slip but also verify the validity of the Navier slip boundary condition. To better understand the fluid slip in this problem, a continuum hydrodynamic model has been formulated based upon the MD verification of the Navier boundary condition and the Newtonian stress. Our model has no adjustable parameter because all the material parameters (density, viscosity, and slip length) are directly determined from MD simulations. Steady-state velocity fields from continuum calculations are in quantitative agreement with those from MD simulations, from the molecular-scale structure to the global flow. The main discovery is as follows. In the immediate vicinity of the corners where moving and fixed solid surfaces intersect, there is a core partial-slip region where the slippage is large at the moving solid surface and decays away from the intersection quickly. In particular, the structure of this core region is nearly independent of the system size. On the other hand, for sufficiently large system, an additional partial-slip region appears where the slippage varies as $1/r$ with $r$ denoting the distance from the corner along the moving solid surface. The existence of this wide power-law region is in accordance with the asymptotic $1/r$ variation of stress and the Navier boundary condition.

  19. Magnetic Refrigeration Technology for High Efficiency Air Conditioning

    SciTech Connect (OSTI)

    Boeder, A; Zimm, C

    2006-09-30T23:59:59.000Z

    Magnetic refrigeration was investigated as an efficient, environmentally friendly, flexible alternative to conventional residential vapor compression central air conditioning systems. Finite element analysis (FEA) models of advanced geometry active magnetic regenerator (AMR) beds were developed to minimize bed size and thus magnet mass by optimizing geometry for fluid flow and heat transfer and other losses. Conventional and magnetocaloric material (MCM) regenerator fabrication and assembly techniques were developed and advanced geometry passive regenerators were built and tested. A subscale engineering prototype (SEP) magnetic air conditioner was designed, constructed and tested. A model of the AMR cycle, combined with knowledge from passive regenerator experiments and FEA results, was used to design the regenerator beds. A 1.5 Tesla permanent magnet assembly was designed using FEA and the bed structure and plenum design was extensively optimized using FEA. The SEP is a flexible magnetic refrigeration platform, with individually instrumented beds and high flow rate and high frequency capability, although the current advanced regenerator geometry beds do not meet performance expectations, probably due to manufacturing and assembly tolerances. A model of the AMR cycle was used to optimize the design of a 3 ton capacity magnetic air conditioner, and the system design was iterated to minimize external parasitic losses such as heat exchanger pressure drop and fan power. The manufacturing cost for the entire air conditioning system was estimated, and while the estimated SEER efficiency is high, the magnetic air conditioning system is not cost competitive as currently configured. The 3 ton study results indicate that there are other applications where magnetic refrigeration is anticipated to have cost advantages over conventional systems, especially applications where magnetic refrigeration, through the use of its aqueous heat transfer fluid, could eliminate intermediate heat exchangers or oil distribution issues found in traditional vapor compression systems.

  20. CX-012271: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Quantitative Characterization of Impacts of Couple Geomechanics and Flow - Lab Experiments/Modeling CX(s) Applied: B3.6 Date: 06/25/2014 Location(s): California Offices(s): National Energy Technology Laboratory

  1. CX-012270: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Quantitative Characterization of Impacts of Couple Geomechanics and Flow - Lab Experiments/Modeling CX(s) Applied: B3.6 Date: 06/25/2014 Location(s): Colorado Offices(s): National Energy Technology Laboratory

  2. CX-010204: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Nalco / Total Flow Loop Polymer Test CX(s) Applied: B1.6, B1.13, B1.18 Date: 02/07/2013 Location(s): Wyoming Offices(s): RMOTC

  3. CX-008967: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Multi-Phase Fluid Flow Simulation Assisted Exploration and Production of Hydrocarbons from Niobrara… CX(s) Applied: B3.1 Date: 08/02/2012 Location(s): South Dakota Offices(s): National Energy Technology Laboratory

  4. CX-008972: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Multi-Phase Fluid Flow Simulation Assisted Exploration and Production of Hydrocarbons from Niobrara… CX(s) Applied: B3.6 Date: 08/01/2012 Location(s): South Dakota Offices(s): National Energy Technology Laboratory

  5. CX-008971: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Multi-Phase Fluid Flow Simulation Assisted Exploration and Production of Hydrocarbons from Niobrara.. CX(s) Applied: A9 Date: 08/01/2012 Location(s): Virginia Offices(s): National Energy Technology Laboratory

  6. CX-008975: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Multi-Phase Fluid Flow Simulation Assisted Exploration and Production of Hydrocarbons from Niobrara… CX(s) Applied: B3.1 Date: 08/01/2012 Location(s): South Dakota Offices(s): National Energy Technology Laboratory

  7. CX-008974: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Multi-Phase Fluid Flow Simulation Assisted Exploration and Production of Hydrocarbons from Niobrara… CX(s) Applied: B3.1 Date: 08/01/2012 Location(s): South Dakota Offices(s): National Energy Technology Laboratory

  8. CX-008968: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Multi-Phase Fluid Flow Simulation Assisted Exploration and Production of Hydrocarbons from Niobrara… CX(s) Applied: B3.1 Date: 08/02/2012 Location(s): South Dakota Offices(s): National Energy Technology Laboratory

  9. CX-007540: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Spectral Signal Processing: A New Approach to Mapping Reservoir Flow and Permeability CX(s) Applied: A9, B3.1 Date: 01/19/2012 Location(s): Hawaii Offices(s): Golden Field Office

  10. CX-008772: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Buried Flow Line from 32-A-34 to 34-AX-34 CX(s) Applied: B2.5, B5.2, B5.4 Date: 07/17/2012 Location(s): Wyoming Offices(s): RMOTC

  11. CX-010968: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Novel Flow Sheet for Low Energy Carbon Dioxide (CO2) Capture Enabled by Biocatalyst Delivery System CX(s) Applied: A9 Date: 09/16/2013 Location(s): Pennsylvania Offices(s): National Energy Technology Laboratory

  12. CX-012166: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Perform Hydrant Flushing, Maintenance, Prove Curb Valves, and Flow Test in C-Area CX(s) Applied: B1.3 Date: 04/23/2014 Location(s): South Carolina Offices(s): Savannah River Operations Office

  13. CX-008622: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Upgrade Room Exhaust Flow Path of HB-Line Confinement Ventilation System CX(s) Applied: B2.2 Date: 06/21/2012 Location(s): South Carolina Offices(s): Savannah River Operations Office

  14. CX-011017: Categorical Exclusion Determination | Department of...

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

    Exclusion Determination Distributed Fiber Optic Arrays: Integrated Temperature and Seismic Sensing for Detection of Carbon Dioxide Flow.. CX(s) Applied: B3.6, B3.11 Date: 09...

  15. CX-011016: Categorical Exclusion Determination | Department of...

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

    Exclusion Determination Distributed Fiber Optic Arrays: Integrated Temperature and Seismic Sensing for Detection of Carbon Dioxide Flow.. CX(s) Applied: B3.6, B3.11 Date: 09...

  16. CX-011724: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Repair Corroded Flow Line Near 33-SX-11 CX(s) Applied: B5.4, B5.6 Date: 12/30/2013 Location(s): Wyoming Offices(s): RMOTC

  17. CX-008917: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Application of Crunch-Flow to Constrain Present and Past Carbon Fluxes at Gas-Hydrate Bearing Sites CX(s) Applied: A9 Date: 08/29/2012 Location(s): Oregon Offices(s): National Energy Technology Laboratory

  18. Event-shape fluctuations and flow correlations in ultra-relativistic heavy-ion collisions

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

    Jia, Jiangyong [Stony Brook Univ., NY (United States). Dept. of Chemistry; Brookhaven National Lab., Upton, NY (United States). Physics Dept.

    2014-12-01T23:59:59.000Z

    I review recent measurements of a large set of flow observables associated with event-shape fluctuations and collective expansion in heavy ion collisions. First, these flow observables are classified and experiment methods are introduced. The experimental results for each type of observables are then presented and compared to theoretical calculations. A coherent picture of initial condition and collective flow based on linear and non-linear hydrodynamic responses is derived, which qualitatively describe most experimental results. I discuss new types of fluctuation measurements that can further our understanding of the event-shape fluctuations and collective expansion dynamics.

  19. Persistent energy flow for a stochastic wave equation model in nonequilibrium statistical mechanics

    E-Print Network [OSTI]

    Lawrence E. Thomas

    2012-04-29T23:59:59.000Z

    We consider a one-dimensional partial differential equation system modeling heat flow around a ring. The system includes a Klein-Gordon wave equation for a field satisfying spatial periodic boundary conditions, as well as Ornstein-Uhlenbeck stochastic differential equations with finite rank dissipation and stochastic driving terms modeling heat baths. There is an energy flow around the ring. In the case of a linear field with different (fixed) bath temperatures, the energy flow can persist even when the interaction with the baths is turned off. A simple example is given.

  20. Mirrored serpentine flow channels for fuel cell

    DOE Patents [OSTI]

    Rock, Jeffrey Allan (Rochester, NY)

    2000-08-08T23:59:59.000Z

    A PEM fuel cell having serpentine flow field channels wherein the input/inlet legs of each channel border the input/inlet legs of the next adjacent channels in the same flow field, and the output/exit legs of each channel border the output/exit legs of the next adjacent channels in the same flow field. The serpentine fuel flow channels may be longer, and may contain more medial legs, than the serpentine oxidant flow channels.

  1. Visualization of Fuel Cell Water Transport and Performance Characterization under Freezing Conditions

    SciTech Connect (OSTI)

    Kandlikar, S.G.; Lu, Z.; Rao, N.; Sergi, J.; Rath, C.; Dade, C.; Trabold, T.; Owejan, J.; Gagliardo, J.; Allen, J.; Yassar, R.S.; Medici, E.; Herescu, A.

    2010-05-30T23:59:59.000Z

    In this program, Rochester Institute of Technology (RIT), General Motors (GM) and Michigan Technological University (MTU) have focused on fundamental studies that address water transport, accumulation and mitigation processes in the gas diffusion layer and flow field channels of the bipolar plate. These studies have been conducted with a particular emphasis on understanding the key transport phenomena which control fuel cell operation under freezing conditions. Technical accomplishments are listed below: • Demonstrated that shutdown air purge is controlled predominantly by the water carrying capacity of the purge stream and the most practical means of reducing the purge time and energy is to reduce the volume of liquid water present in the fuel cell at shutdown. The GDL thermal conductivity has been identified as an important parameter to dictate water accumulation within a GDL. • Found that under the normal shutdown conditions most of the GDL-level water accumulation occurs on the anode side and that the mass transport resistance of the membrane electrode assembly (MEA) thus plays a critically important role in understanding and optimizing purge. • Identified two-phase flow patterns (slug, film and mist flow) in flow field channel, established the features of each pattern, and created a flow pattern map to characterize the two-phase flow in GDL/channel combination. • Implemented changes to the baseline channel surface energy and GDL materials and evaluated their performance with the ex situ multi-channel experiments. It was found that the hydrophilic channel (contact angle ? ? 10?) facilitates the removal of liquid water by capillary effects and by reducing water accumulation at the channel exit. It was also found that GDL without MPL promotes film flow and shifts the slug-to-film flow transition to lower air flow rates, compared with the case of GDL with MPL. • Identified a new mechanism of water transport through GDLs based on Haines jump mechanism. The breakdown and redevelopment of the water paths in GDLs lead to an intermittent water drainage behavior, which is characterized by dynamic capillary pressure and changing of breakthrough location. MPL was found to not only limit the number of water entry locations into the GDL (thus drastically reducing water saturation), but also stabilizes the water paths (or morphology). • Simultaneously visualized the water transport on cathode and anode channels of an operating fuel cell. It was found that under relatively dry hydrogen/air conditions at lower temperatures, the cathode channels display a similar flow pattern map to the ex-situ experiments under similar conditions. Liquid water on the anode side is more likely formed via condensation of water vapor which is transported through the anode GDL. • Investigated the water percolation through the GDL with pseudo-Hele-Shaw experiments and simulated the capillary-driven two-phase flow inside gas diffusion media, with the pore size distributions being modeled by using Weibull distribution functions. The effect of the inclusion of the microporous layer in the fuel cell assembly was explored numerically. • Developed and validated a simple, reliable computational tool for predicting liquid water transport in GDLs. • Developed a new method of determining the pore size distribution in GDL using scanning electron microscope (SEM) image processing, which allows for separate characterization of GDL wetting properties and pore size distribution. • Determined the effect of surface wettability and channel cross section and bend dihedral on liquid holdup in fuel cell flow channels. A major thrust of this research program has been the development of an optimal combination of materials, design features and cell operating conditions that achieve a water management strategy which facilitates fuel cell operation under freezing conditions. Based on our various findings, we have made the final recommendation relative to GDL materials, bipolar design and surface properties, and the combination of materials, design featur

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

    SciTech Connect (OSTI)

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

    2006-07-01T23:59:59.000Z

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

  3. Rheo-optical determination of flow birefringence and flow dichroism with the pulsed laser method

    E-Print Network [OSTI]

    Rheo-optical determination of flow birefringence and flow dichroism with the pulsed laser method online 29 August 2006 Rheo-optical measurements of the flow birefringence, flow dichroism systems under flow. However, the standard setup of an optical train, using phase modulation for the rheo-optical

  4. Connectivity due to preferential flow controls water flow and solute transport at the hillslope scale

    E-Print Network [OSTI]

    Weiler, Markus

    feedback, flow through the fractured bedrock, kinematic wave routing and flow through discrete preferentialConnectivity due to preferential flow controls water flow and solute transport at the hillslope the major controls on water flow and solute transport at the hillslope scale remains a major topic

  5. Time-dependent and outflow boundary conditions for Dissipative Particle Dynamics

    SciTech Connect (OSTI)

    Lei Huan [Division of Applied Mathematics, Brown University, Providence, RI 02912 (United States); Fedosov, Dmitry A. [Division of Applied Mathematics, Brown University, Providence, RI 02912 (United States); Institut fuer Festkoerperforschung, Forschungszentrum Juelich, 52425 Juelich (Germany); Karniadakis, George Em, E-mail: George_Karniadakis@brown.ed [Division of Applied Mathematics, Brown University, Providence, RI 02912 (United States)

    2011-05-10T23:59:59.000Z

    We propose a simple method to impose both no-slip boundary conditions at fluid-wall interfaces and at outflow boundaries in fully developed regions for Dissipative Particle Dynamics (DPD) fluid systems. The procedure to enforce the no-slip condition is based on a velocity-dependent shear force, which is a generalized force to represent the presence of the solid-wall particles and to maintain locally thermodynamic consistency. We show that this method can be implemented in both steady and time-dependent fluid systems and compare the DPD results with the continuum limit (Navier-Stokes) results. We also develop a force-adaptive method to impose the outflow boundary conditions for fully developed flow with unspecified outflow velocity profile or pressure value. We study flows over the backward-facing step and in idealized arterial bifurcations using a combination of the two new boundary methods with different flow rates. Finally, we explore the applicability of the outflow method in time-dependent flow systems. The outflow boundary method works well for systems with Womersley number of O(1), i.e. when the pressure and flowrate at the outflow are approximately in-phase.

  6. Cumulant expansions for atmospheric flows

    E-Print Network [OSTI]

    Ait-Chaalal, Farid; Meyer, Bettina; Marston, J B

    2015-01-01T23:59:59.000Z

    The equations governing atmospheric flows are nonlinear, and consequently the hierarchy of cumulant equations is not closed. But because atmospheric flows are inhomogeneous and anisotropic, the nonlinearity may manifests itself only weakly through interactions of mean fields with disturbances such as thermals or eddies. In such situations, truncations of the hierarchy of cumulant equations hold promise as a closure strategy. We review how truncations at second order can be used to model and elucidate the dynamics of turbulent atmospheric flows. Two examples are considered. First, we study the growth of a dry convective boundary layer, which is heated from below, leading to turbulent upward energy transport and growth of the boundary layer. We demonstrate that a quasilinear truncation of the equations of motion, in which interactions of disturbances among each other are neglected but interactions with mean fields are taken into account, can successfully capture the growth of the convective boundary layer. Seco...

  7. Monitoring probe for groundwater flow

    DOE Patents [OSTI]

    Looney, B.B.; Ballard, S.

    1994-08-23T23:59:59.000Z

    A monitoring probe for detecting groundwater migration is disclosed. The monitor features a cylinder made of a permeable membrane carrying an array of electrical conductivity sensors on its outer surface. The cylinder is filled with a fluid that has a conductivity different than the groundwater. The probe is placed in the ground at an area of interest to be monitored. The fluid, typically saltwater, diffuses through the permeable membrane into the groundwater. The flow of groundwater passing around the permeable membrane walls of the cylinder carries the conductive fluid in the same general direction and distorts the conductivity field measured by the sensors. The degree of distortion from top to bottom and around the probe is precisely related to the vertical and horizontal flow rates, respectively. The electrical conductivities measured by the sensors about the outer surface of the probe are analyzed to determine the rate and direction of the groundwater flow. 4 figs.

  8. Monitoring probe for groundwater flow

    DOE Patents [OSTI]

    Looney, Brian B. (Aiken, SC); Ballard, Sanford (Albuquerque, NM)

    1994-01-01T23:59:59.000Z

    A monitoring probe for detecting groundwater migration. The monitor features a cylinder made of a permeable membrane carrying an array of electrical conductivity sensors on its outer surface. The cylinder is filled with a fluid that has a conductivity different than the groundwater. The probe is placed in the ground at an area of interest to be monitored. The fluid, typically saltwater, diffuses through the permeable membrane into the groundwater. The flow of groundwater passing around the permeable membrane walls of the cylinder carries the conductive fluid in the same general direction and distorts the conductivity field measured by the sensors. The degree of distortion from top to bottom and around the probe is precisely related to the vertical and horizontal flow rates, respectively. The electrical conductivities measured by the sensors about the outer surface of the probe are analyzed to determine the rate and direction of the groundwater flow.

  9. Effect of charged particle's multiplicity fluctuations on flow harmonics in even-by-event hydrodynamics

    E-Print Network [OSTI]

    Chaudhuri, A K

    2012-01-01T23:59:59.000Z

    In nucleon-nucleon collisions, charged particle's multiplicity fluctuates. We have studied the effect of multiplicity fluctuation on flow harmonics in nucleus-nucleus collision in event-by-event hydrodynamics. Assuming that the charged particle's multiplicity fluctuations are governed by the negative binomial distribution, the Monte-Carlo Glauber model of initial condition is generalised to include the fluctuations. Explicit simulations with the generalised Monte-Carlo Glauber model initial conditions indicate that the multiplicity fluctuations do not have large effect on the flow harmonics.

  10. Effect of charged particle's multiplicity fluctuations on flow harmonics in even-by-event hydrodynamics

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2013-03-19T23:59:59.000Z

    In nucleon-nucleon collisions, charged particle's multiplicity fluctuates. We have studied the effect of multiplicity fluctuation on flow harmonics in nucleus-nucleus collision in event-by-event hydrodynamics. Assuming that the charged particle's multiplicity fluctuations are governed by the negative binomial distribution, the Monte-Carlo Glauber model of initial condition is generalised to include the fluctuations. Explicit simulations with the generalised Monte-Carlo Glauber model initial conditions indicate that the multiplicity fluctuations do not have large effect on the flow harmonics.

  11. High gas flow alpha detector

    DOE Patents [OSTI]

    Bolton, R.D.; Bounds, J.A.; Rawool-Sullivan, M.W.

    1996-05-07T23:59:59.000Z

    An alpha detector for application in areas of high velocity gas flows, such as smokestacks and air vents. A plurality of spaced apart signal collectors are placed inside an enclosure, which would include smokestacks and air vents, in sufficient numbers to substantially span said enclosure so that gas ions generated within the gas flow are electrostatically captured by the signal collector means. Electrometer means and a voltage source are connected to the signal collectors to generate an electrical field between adjacent signal collectors, and to indicate a current produced through collection of the gas ions by the signal collectors. 4 figs.

  12. High gas flow alpha detector

    DOE Patents [OSTI]

    Bolton, Richard D. (Los Alamos, NM); Bounds, John A. (Los Alamos, NM); Rawool-Sullivan, Mohini W. (Los Alamos, NM)

    1996-01-01T23:59:59.000Z

    An alpha detector for application in areas of high velocity gas flows, such as smokestacks and air vents. A plurality of spaced apart signal collectors are placed inside an enclosure, which would include smokestacks and air vents, in sufficient numbers to substantially span said enclosure so that gas ions generated within the gas flow are electrostatically captured by the signal collector means. Electrometer means and a voltage source are connected to the signal collectors to generate an electrical field between adjacent signal collectors, and to indicate a current produced through collection of the gas ions by the signal collectors.

  13. Non-Newtonian fluid flow

    E-Print Network [OSTI]

    Osinski, Charles Anthony

    1963-01-01T23:59:59.000Z

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

  14. Nuclear reactor downcomer flow deflector

    DOE Patents [OSTI]

    Gilmore, Charles B. (Greensburg, PA); Altman, David A. (Pittsburgh, PA); Singleton, Norman R. (Murrysville, PA)

    2011-02-15T23:59:59.000Z

    A nuclear reactor having a coolant flow deflector secured to a reactor core barrel in line with a coolant inlet nozzle. The flow deflector redirects incoming coolant down an annulus between the core barrel and the reactor vessel. The deflector has a main body with a front side facing the fluid inlet nozzle and a rear side facing the core barrel. The rear side of the main body has at least one protrusion secured to the core barrel so that a gap exists between the rear side of the main body adjacent the protrusion and the core barrel. Preferably, the protrusion is a relief that circumscribes the rear side of the main body.

  15. Interfacial flows in corrugated microchannels: flow regimes, transitions and hysteresis

    E-Print Network [OSTI]

    Feng, James J.

    , 1266-1276 (2011), doi:10.1016/j.ijmultiphaseflow.2011.08.003 #12;model, microfluidics, porous media 1 of displacing oil by water in enhanced oil recovery (Marle, 1981; Lenormand et al., 1988). More recently on hy- drodynamic principles and concrete flow mechanisms. In fact, conflicting assumptions have been

  16. EMSL - Subsurface Flow and Transport

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

    capabilities High-pressuretemperature cells for research at reservoir conditions Dual energy gamma radiation system Integrated hydraulic properties apparatus Relative permeability...

  17. Triple-decker: Interfacing atomistic-mesoscopic-continuum flow regimes

    SciTech Connect (OSTI)

    Fedosov, Dmitry A. [Division of Applied Mathematics, Brown University, 182 George St., Box F, Providence, RI 02912 (United States); Karniadakis, George Em [Division of Applied Mathematics, Brown University, 182 George St., Box F, Providence, RI 02912 (United States)], E-mail: gk@dam.brown.edu

    2009-03-01T23:59:59.000Z

    Multiscale flow phenomena in microfluidic and biomedical applications require the use of heterogeneous modeling approaches. In this paper we present a hybrid method based on coupling the Molecular Dynamics (MD) method, the Dissipative Particle Dynamics (DPD) method, and the incompressible Navier-Stokes (NS) equations. MD, DPD, and NS are formulated in separate subdomains and are coupled via an overlapping region by communicating state information at the subdomain boundaries. Imposition of boundary conditions in the MD and DPD systems involves particle insertion and deletion, specular wall reflection and body force terms. The latter includes a boundary pressure force in order to minimize near-boundary density fluctuations, and an adaptive shear force which enforces the tangential velocity component of boundary conditions. The triple-decker algorithm is verified for prototype flows, including simple and multi-layer fluids (Couette, Poiseuille, and lid-driven cavity), using highly accurate reference solutions. A zero-thickness interface is also possible if it is aligned with the flow streamlines.

  18. The conformation change of model polymers in stochastic flow fields: Flow through fixed beds

    E-Print Network [OSTI]

    Shaqfeh, Eric

    The conformation change of model polymers in stochastic flow fields: Flow through fixed beds Alisa that as a polymer solution flows through a fixed bed, the pressure drop neces- sary to pump the solution may

  19. University of Exeter Conditions of Employment June 2008 1 CONDITIONS OF EMPLOYMENT

    E-Print Network [OSTI]

    Mumby, Peter J.

    University of Exeter Conditions of Employment ­ June 2008 1 CONDITIONS OF EMPLOYMENT (Approved Agreement at the University of Exeter agreed in July 2006, the following conditions of employment apply conditions of employment which apply equally to all staff. The appendices detail conditions of employment

  20. Wind Turbine Drivetrain Condition Monitoring - An Overview

    SciTech Connect (OSTI)

    Sheng, S; Veers, P.

    2011-10-01T23:59:59.000Z

    This paper provides an overview of wind turbine drivetrain condition monitoring based on presentations from a condition monitoring workshop organized by the National Renewable Energy Laboratory in 2009 and on additional references.

  1. A New Approach to Industrial Air Conditioning

    E-Print Network [OSTI]

    Gravenstreter, T.

    1982-01-01T23:59:59.000Z

    -dryer Systems Division, has marketed industrial drying machinery. These heat reactivated dryers can handle latent loads in industrial air conditioning systems. Through waste heat conservation, air conditioning costs can be reduced 25 to 50%, with applications...

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

    SciTech Connect (OSTI)

    Coutts, D.A.

    1993-09-09T23:59:59.000Z

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

  3. Embrittlement and Flow Localization in Reactor Structural Materials

    SciTech Connect (OSTI)

    Xianglin Wu; Xiao Pan; James Stubbins

    2006-10-06T23:59:59.000Z

    Many reactor components and structural members are made from metal alloys due, in large part, to their strength and ability to resist brittle fracture by plastic deformation. However, brittle fracture can occur when structural material cannot undergo extensive, or even limited, plastic deformation due to irradiation exposure. Certain irradiation conditions lead to the development of a damage microstructure where plastic flow is limited to very small volumes or regions of material, as opposed to the general plastic flow in unexposed materials. This process is referred to as flow localization or plastic instability. The true stress at the onset of necking is a constant regardless of the irradiation level. It is called 'critical stress' and this critical stress has strong temperature dependence. Interrupted tensile testes of 316L SS have been performed to investigate the microstructure evolution and competing mechanism between mechanic twinning and planar slip which are believed to be the controlling mechanism for flow localization. Deformation twinning is the major contribution of strain hardening and good ductility for low temperatures, and the activation of twinning system is determined by the critical twinning stress. Phases transform and texture analyses are also discussed in this study. Finite element analysis is carried out to complement the microstructural analysis and for the prediction of materaials performance with and without stress concentration and irradiation.

  4. Laminar-turbulent separatrix in a boundary layer flow

    E-Print Network [OSTI]

    Biau, Damien

    2013-01-01T23:59:59.000Z

    The transitional boundary layer flow over a flat plate is investigated. The boundary layer flow is known to develop unstable Tollmien-Schlichting waves above a critical value of the Reynolds number. However, it is also known that this transition can be observed for sub-critical Reynolds numbers. In that case, the basin of attraction of the laminar state coexists with the sustained turbulence. In this article, the trajectory on the separatrix between these two states is simulated. The state on the separatrix is independent from the initial condition and is dynamically connected to both the laminar flow and the turbulence. Such an edge state provides information regarding the basic features of the transitional flow. The solution takes the form of a low speed streak, flanked by two quasi-streamwise sinuous vortices. The shape of the streaks is close to that simulated with the linear optimal perturbation method. This solution is compared to existing results concerning streak breakdown. The simulations are realize...

  5. Flow calculations for Yucca Mountain groundwater travel time (GWTT-95)

    SciTech Connect (OSTI)

    Altman, S.J.; Arnold, B.W.; Barnard, R.W.; Barr, G.E.; Ho, C.K.; McKenna, S.A.; Eaton, R.R.

    1996-09-01T23:59:59.000Z

    In 1983, high-level radioactive waste repository performance requirements related to groundwater travel time were defined by NRC subsystem regulation 10 CFR 60.113. Although DOE is not presently attempting to demonstrate compliance with that regulation, understanding of the prevalence of fast paths in the groundwater flow system remains a critical element of any safety analyses for a potential repository system at Yucca Mountain, Nevada. Therefore, this analysis was performed to allow comparison of fast-path flow against the criteria set forth in the regulation. Models developed to describe the conditions for initiation, propagation, and sustainability of rapid groundwater movement in both the unsaturated and saturated zones will form part of the technical basis for total- system analyses to assess site viability and site licensability. One of the most significant findings is that the fastest travel times in both unsaturated and saturated zones are in the southern portion of the potential repository, so it is recommended that site characterization studies concentrate on this area. Results support the assumptions regarding the importance of an appropriate conceptual model of groundwater flow and the incorporation of heterogeneous material properties into the analyses. Groundwater travel times are sensitive to variation/uncertainty in hydrologic parameters and in infiltration flux at upper boundary of the problem domain. Simulated travel times are also sensitive to poorly constrained parameters of the interaction between flow in fractures and in the matrix.

  6. Internat. Congress on Science & Technology of Steelmaking, Charlotte, NC, May 9-12, AIST, Warrendale, PA, 2005, pp. 847-861. Modeling of Continuous-Casting Defects Related to Mold Fluid Flow

    E-Print Network [OSTI]

    Thomas, Brian G.

    that is neither too cold nor too turbulent. In addition, the flow conditions should minimize exposure to air optimization. Fluid flow in the mold is controlled by many design parameters and operating conditions. Nozzle geometry is the most important, and includes the bore size, port angle, port opening size, nozzle wall

  7. Conditional averaging on volumetric velocity fields for analysis of the pseudo-periodic organization of jet-in-crossflow vortices

    E-Print Network [OSTI]

    Cambonie, Tristan

    2014-01-01T23:59:59.000Z

    Volumetric velocimetry measurements have been performed on a round jet in crossflow (JICF). Two kind of conditional averaging process are presented : a global conditional average (GCA) and a local conditional average (LCA). Vortices crossing the JICF symmetry plane are used to quantify the jet pseudo-periodicity leading to the GCA and LCA definitions. Because they make possible to improve the velocity field resolution as well as to significantly reduce the experimental noise, these conditional averages are an interesting and efficient way to study the instantaneous swirling structures of this instantaneous flow.

  8. Superconducting flux flow digital circuits

    DOE Patents [OSTI]

    Hietala, V.M.; Martens, J.S.; Zipperian, T.E.

    1995-02-14T23:59:59.000Z

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs) are disclosed. Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics. 8 figs.

  9. Neutrino Factory Mercury Flow Loop

    E-Print Network [OSTI]

    McDonald, Kirk

    ­ Could require double containment of mercury ­ Chase will certainly have a drain back into hot cell Decay 2010 #12;Hg Flow Overflow · Minimize pressure drops through piping Overflow Mercury Drain drops Gravity Drain Beam Dumptransitioning to 1 cm nozzle · Actual NF Hg inventory may reach SNS Gravity Drain

  10. Message Flow Modeling Oscar Nierstrasz

    E-Print Network [OSTI]

    Nierstrasz, Oscar

    Message Flow Modeling Oscar Nierstrasz and Dennis Tsichritzis Computer Systems Research Group University of Toronto ABSTRACT A message management system provides users with a facility for automatically handling messages. This paper describes a technique for characterizing the behaviour of such a system

  11. Collective flow in small systems

    E-Print Network [OSTI]

    Piotr Bozek; Wojciech Broniowski

    2014-07-24T23:59:59.000Z

    The large density of matter in the interaction region of the proton-nucleus or deuteron-nucleus collisions enables the collective expansion of the fireball. Predictions of the hydrodynamic model for the asymmetric transverse flow are presented and compared to experimental data.

  12. Stopping Cooling Flows with Jets

    E-Print Network [OSTI]

    Fabrizio Brighenti; William G. Mathews

    2006-01-24T23:59:59.000Z

    We describe 2D gasdynamical models of jets that carry mass as well as energy to the hot gas in galaxy clusters. These flows have many attractive attributes for solving the galaxy cluster cooling flow problem: Why the hot gas temperature and density profiles resemble cooling flows but show no spectral evidence of cooling to low temperatures. Using an approximate model for the cluster A1795, we show that mass-carrying jets can reduce the overall cooling rate to or below the low values implied by X-ray spectra. Biconical subrelativistic jets, described with several ad hoc parameters, are assumed to be activated when gas flows toward or cools near a central supermassive black hole. As the jets proceed out from the center they entrain more and more ambient gas. The jets lose internal pressure by expansion and are compressed by the ambient cluster gas, becoming rather difficult to observe. For a wide variety of initial jet parameters and several feedback scenarios the global cooling can be suppressed for many Gyrs while maintaining cluster temperature profiles similar to those observed. The intermittancy of the feedback generates multiple generations of X-ray cavities similar to those observed in the Perseus Cluster and elsewhere.

  13. Flow preconditioner for electrostatic precipitator

    SciTech Connect (OSTI)

    Honacker, H.; Drlik, R.J.

    1980-01-01T23:59:59.000Z

    A flow preconditioner for an electrostatic precipitator removes particulate matter from a stream of polluted gas immediately after it passes through a tangential inlet at the lower end of a vertical cylindrical housing and straightens and divides the stream into laminations parallel to the axis of the housing. It comprises an annular ledge or choke ring extending inwardly from said housing above the inlet and an assembly of vanes above said ledge extending radially from the axis of the housing and angularly spaced apart. Each of said vanes has a flow receiving edge directed toward said inlet, a curved portion extending upwardly and away from said inlet, and a flat portion extending upwardly from said curved portion in a plane parallel to the housing axis. The curved portion of each vane defines a trough having a camber which gradually decreases along its span from the outer end of the vane towards the axis of the housng, together with means to vary the centrifugal flow distribution relative to the housing to render the preconditioner adjustable for various flow capacities.

  14. Documenting Organizational Process Flow Modeling

    E-Print Network [OSTI]

    Schweik, Charles M.

    1 Documenting Organizational Processes or Process Flow Modeling Analysis Phase ­ Three Steps that describes (1) the current, and (2) the future structure of an organizational process ·"Natural language ­ An overview of an organizational system showing · system boundaries, · external entities that interact

  15. Flow assurance and multiphase pumping 

    E-Print Network [OSTI]

    Nikhar, Hemant G.

    2009-05-15T23:59:59.000Z

    -in-Pipe?????????????????????????????????????. 42 Non-Jacketed Insulation Systems?????????????????????????? 42 Syntactic Insulation?????????????????????????????????. 42 Heating?????????????????????????????????????????? 43 Pipeline Configurations for Heating????????????????????????? 45 Subsea... Various Chemicals Used in Oil and Gas Production Operations????????. 38 15 Seawater Temperature Gradients???????????????????????.. 43 16 Flow Model Schematic?????????????????????????????.. 44 17 Deliverability Affected by Cooling Effect of Pipeline...

  16. Comments on "Microscale flow visualization"

    E-Print Network [OSTI]

    A. Kwang-Hua Chu

    2005-10-22T23:59:59.000Z

    We make comments on the presentation of Sinton's paper (Microfluidics and Nanofluidics {\\bf 1}: 2, 2004) about the microscale flow visualization since the effects of the roughness along the microfabricated wall upon the current macroflow visualization methods could be significant and cannot be neglected in microdomain and even nanodomain.

  17. Rinse trough with improved flow

    DOE Patents [OSTI]

    O`Hern, T.J.; Grasser, T.W.

    1998-08-11T23:59:59.000Z

    Novel rinse troughs accomplish thorough uniform rinsing. The troughs are suitable for one or more essentially planar objects having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs provide uniform rinse fluid flow over the objects` surfaces to accomplish a more thorough rinse than prior art troughs. 5 figs.

  18. Building America Webinar: Retrofitting Central Space Conditioning...

    Energy Savers [EERE]

    Webinar: Retrofitting Central Space Conditioning Strategies for Multifamily Buildings - Steam Systems, Retrofit Measure Packages, Hydronic Systems Building America Webinar:...

  19. Space Conditioning Standing Technical Committee Strategic Plan

    Broader source: Energy.gov [DOE]

    This strategic plan document outlines the gaps, barriers, and opportunities identified by the Building America Space Conditioning Standing Technical Committee.

  20. Conditioned stochastic differential equations: theory, examples and ...

    E-Print Network [OSTI]

    2002-07-03T23:59:59.000Z

    Keywords: Brownian bridge; Conditioning; Initial enlargement of filtration; Exponential generalization of. Pitman's 2M-X theorem; Filtering; Portfolio optimization.

  1. Building America Webinar: Retrofitting Central Space Conditioning...

    Energy Savers [EERE]

    Strategies for Multifamily Buildings - Control strategies to improve hydronic space heating performance Building America Webinar: Retrofitting Central Space Conditioning...

  2. Building America Webinar: Retrofitting Central Space Conditioning...

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

    Introduction Building America Webinar: Retrofitting Central Space Conditioning Strategies for Multifamily Buildings - Introduction This presentation serves as the introduction to...

  3. Liquid metal Flow Meter - Final Report

    SciTech Connect (OSTI)

    Andersen, C.; Hoogendoom, S.; Hudson, B.; Prince, J.; Teichert, K.; Wood, J.; Chase, K.

    2007-01-30T23:59:59.000Z

    Measuring the flow of liquid metal presents serious challenges. Current commercially-available flow meters use ultrasonic, electromagnetic, and other technologies to measure flow, but are inadequate for liquid metal flow measurement because of the high temperatures required by most liquid metals. As a result of the reactivity and high temperatures of most liquid metals, corrosion and leakage become very serious safety concerns. The purpose of this project is to develop a flow meter for Lockheed Martin that measures the flow rate of molten metal in a conduit.

  4. A numerical investigation on the vortex formation and flow separation of the oscillatory flow in jet pumps

    E-Print Network [OSTI]

    Oosterhuis, Joris P; Wilcox, Douglas; van der Meer, Theo

    2015-01-01T23:59:59.000Z

    A two-dimensional computational fluid dynamics model is used to predict the oscillatory flow through a tapered cylindrical tube section (jet pump) placed in a larger outer tube. Due to the shape of the jet pump, there will exist an asymmetry in the hydrodynamic end effects which will cause a time-averaged pressure drop to occur that can be used to cancel Gedeon streaming in a closed-loop thermoacoustic device. The performance of two jet pump geometries with different taper angles is investigated. A specific time-domain impedance boundary condition is implemented in order to simulate traveling acoustic wave conditions. It is shown that by scaling the acoustic displacement amplitude to the jet pump dimensions, similar minor losses are observed independent of the jet pump geometry. Four different flow regimes are distinguished and the observed flow phenomena are related to the jet pump performance. The simulated jet pump performance is compared to an existing quasi-steady approximation which is shown to only be ...

  5. Structure of processes in flow reactor and closed reactor: Flow reactor

    E-Print Network [OSTI]

    Greifswald, Ernst-Moritz-Arndt-Universität

    Structure of processes in flow reactor and closed reactor: Flow reactor Closed reactor Active Zone -- chemical quasi- equilibria, similarity principles and macroscopic kinetics", in: Lectures on Plasma Physics

  6. Coherence imaging of scrape-off-layer and divertor impurity flows in the Mega Amp Spherical Tokamak (invited)

    SciTech Connect (OSTI)

    Silburn, S. A., E-mail: s.a.silburn@durham.ac.uk; Sharples, R. M. [Centre for Advanced Instrumentation, Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Harrison, J. R.; Meyer, H.; Michael, C. A. [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Howard, J. [Plasma Research Laboratory, Australian National University, Canberra, ACT 0200 (Australia); Gibson, K. J. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom)

    2014-11-15T23:59:59.000Z

    A new coherence imaging Doppler spectroscopy diagnostic has been deployed on the UK’s Mega Amp Spherical Tokamak for scrape-off-layer and divertor impurity flow measurements. The system has successfully obtained 2D images of C III, C II, and He II line-of-sight flows, in both the lower divertor and main scrape-off-layer. Flow imaging has been obtained at frame rates up to 1 kHz, with flow resolution of around 1 km/s and spatial resolution better than 1 cm, over a 40° field of view. C III data have been tomographically inverted to obtain poloidal profiles of the parallel impurity flow in the divertor under various conditions. In this paper we present the details of the instrument design, operation, calibration, and data analysis as well as a selection of flow imaging results which demonstrate the diagnostic's capabilities.

  7. Plugging of intersubassembly gaps by downward flowing molten steel. [LMFBR

    SciTech Connect (OSTI)

    Sienicki, J.J.; Spencer, B.W.

    1984-01-01T23:59:59.000Z

    In the assessment of the meltout phase of an LMFBR hypothetical core disruptive accident, a pathway for the escape of molten fuel from the disrupted core is provided by the narrow channels separating adjacent subassemblies. However, the removal of fuel through intersubassembly gaps might be impeded by steel blockage formation, if molten steel is postulated to enter the gap network ahead of disrupted fuel. Reported here are the results of an analysis of the conduction freezing controlled penetration behavior of molten steel flowing downward through the voided (of sodium) gap channels nominally separating adjacent subassemblies below the active core region. The objective is to determine the range of conditions under which the steel is predicted to be deposited as a thin crust on the channel walls leaving an open pathway remaining for subsequent fuel flow instead of forming a complete plug which closes off the gap channel and obstructs fuel removal immediately thereafter.

  8. Subsurface Flow and Contaminant Transport Documentation and User's Guide

    SciTech Connect (OSTI)

    Aleman, S.E.

    1999-07-28T23:59:59.000Z

    This report documents a finite element code designed to model subsurface flow and contaminant transport, named FACT. FACT is a transient three-dimensional, finite element code designed to simulate isothermal groundwater flow, moisture movement, and solute transport in variably saturated and fully saturated subsurface porous media. The code is designed specifically to handle complex multi-layer and/or heterogeneous aquifer systems in an efficient manner and accommodates a wide range of boundary conditions. Additionally, 1-D and 2-D (in Cartesian coordinates) problems are handled in FACT by simply limiting the number of elements in a particular direction(s) to one. The governing equations in FACT are formulated only in Cartesian coordinates.

  9. Desiccant Enhanced Evaporative Air Conditioning: Parametric Analysis and Design; Preprint

    SciTech Connect (OSTI)

    Woods, J.; Kozubal, E.

    2012-10-01T23:59:59.000Z

    This paper presents a parametric analysis using a numerical model of a new concept in desiccant and evaporative air conditioning. The concept consists of two stages: a liquid desiccant dehumidifier and a dew-point evaporative cooler. Each stage consists of stacked air channel pairs separated by a plastic sheet. In the first stage, a liquid desiccant film removes moisture from the process (supply-side) air through a membrane. An evaporatively-cooled exhaust airstream on the other side of the plastic sheet cools the desiccant. The second-stage indirect evaporative cooler sensibly cools the dried process air. We analyze the tradeoff between device size and energy efficiency. This tradeoff depends strongly on process air channel thicknesses, the ratio of first-stage to second-stage area, and the second-stage exhaust air flow rate. A sensitivity analysis reiterates the importance of the process air boundary layers and suggests a need for increasing airside heat and mass transfer enhancements.

  10. Soluble Lead Flow Battery: Soluble Lead Flow Battery Technology

    SciTech Connect (OSTI)

    None

    2010-09-01T23:59:59.000Z

    GRIDS Project: General Atomics is developing a flow battery technology based on chemistry similar to that used in the traditional lead-acid battery found in nearly every car on the road today. Flow batteries store energy in chemicals that are held in tanks outside the battery. When the energy is needed, the chemicals are pumped through the battery. Using the same basic chemistry as a traditional battery but storing its energy outside of the cell allows for the use of very low cost materials. The goal is to develop a system that is far more durable than today’s lead-acid batteries, can be scaled to deliver megawatts of power, and which lowers the cost of energy storage below $100 per kilowatt hour.

  11. High Energy Efficiency Air Conditioning

    SciTech Connect (OSTI)

    Edward McCullough; Patrick Dhooge; Jonathan Nimitz

    2003-12-31T23:59:59.000Z

    This project determined the performance of a new high efficiency refrigerant, Ikon B, in a residential air conditioner designed to use R-22. The refrigerant R-22, used in residential and small commercial air conditioners, is being phased out of production in developed countries beginning this year because of concerns regarding its ozone depletion potential. Although a replacement refrigerant, R-410A, is available, it operates at much higher pressure than R-22 and requires new equipment. R-22 air conditioners will continue to be in use for many years to come. Air conditioning is a large part of expensive summer peak power use in many parts of the U.S. Previous testing and computer simulations of Ikon B indicated that it would have 20 - 25% higher coefficient of performance (COP, the amount of cooling obtained per energy used) than R-22 in an air-cooled air conditioner. In this project, a typical new R-22 residential air conditioner was obtained, installed in a large environmental chamber, instrumented, and run both with its original charge of R-22 and then with Ikon B. In the environmental chamber, controlled temperature and humidity could be maintained to obtain repeatable and comparable energy use results. Tests with Ikon B included runs with and without a power controller, and an extended run for several months with subsequent analyses to check compatibility of Ikon B with the air conditioner materials and lubricant. Baseline energy use of the air conditioner with its original R-22 charge was measured at 90 deg F and 100 deg F. After changeover to Ikon B and a larger expansion orifice, energy use was measured at 90 deg F and 100 deg F. Ikon B proved to have about 19% higher COP at 90 deg F and about 26% higher COP at 100 deg F versus R-22. Ikon B had about 20% lower cooling capacity at 90 deg F and about 17% lower cooling capacity at 100 deg F versus R-22 in this system. All results over multiple runs were within 1% relative standard deviation (RSD). All of these values agree well with previous results and computer simulations of Ikon B performance versus R-22. The lower cooling capacity of Ikon B is not a concern unless a particular air conditioner is near its maximum cooling capacity in application. Typically, oversized A/C systems are installed by contractors to cover contingencies. In the extended run with Ikon B, which lasted about 4.5 months at 100 deg F ambient temperature and 68% compressor on time, the air conditioner performed well with no significant loss of energy efficiency. Post-run analysis of the refrigerant, compressor lubricant oil, compressor, compressor outlet tubing, and the filter/dryer showed minor effects but nothing that was considered significant. The project was very successful. All objectives were achieved, and the performance of Ikon B indicates that it can easily be retrofitted into R-22 air conditioners to give 15 - 20% energy savings and a 1 - 3 year payback of retrofit costs depending on location and use. Ikon B has the potential to be a successful commercial product.

  12. air conditioning plants: Topics by E-print Network

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

    - TxSpace Summary: The primarysecondary piping systems are often employed in large chiller plant Systems. Normally, the primary flow becomes more than secondary flow, and...

  13. air conditioning plant: Topics by E-print Network

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

    - TxSpace Summary: The primarysecondary piping systems are often employed in large chiller plant Systems. Normally, the primary flow becomes more than secondary flow, and...

  14. Decentralized information flow control on a cluster

    E-Print Network [OSTI]

    Cliffer, Natan Tsvi Cohen

    2007-01-01T23:59:59.000Z

    Information flow control security models can prevent programs from divulging sensitive information in unexpected ways. There has been significant work on tracking information flow between processes in the same computer at ...

  15. Fluid Gravity Engineering Rocket motor flow analysis

    E-Print Network [OSTI]

    Anand, Mahesh

    Fluid Gravity Engineering Capability · Rocket motor flow analysis -Internal (performance) -External (plume / contamination) · Effect on landing site (surface alteration) -In-depth flow through porous young scientists/engineers Fluid Gravity Engineering Ltd #12;

  16. gtp_flow_power_estimator.xlsx

    Broader source: Energy.gov [DOE]

    This simple spreadsheet model estimates either the flow rate required to produce a specified level of power output, or the power output that can be produced from a specified flow rate.

  17. An optical investigation of air particle flows

    E-Print Network [OSTI]

    McCluskey, Denise R

    This thesis is a fundamental study of air-particle flow fields where the experimental parameters are characteristics of coal-fired electricity generating stations. The optical flow field measurement technique Particle Image Velocimetry (PIV...

  18. Numerical simulation of electrokinetically driven micro flows

    E-Print Network [OSTI]

    Hahm, Jungyoon

    2005-11-01T23:59:59.000Z

    in a micro-channel is studied. External electric field, flow rate of pressure driven flow, and geometry in the micro-channel are manipulated to obtain the focusing point, which led to determination of the electrophoretic mobility and (relative...

  19. Numerical study of transition to supersonic flows in the edge plasma

    SciTech Connect (OSTI)

    Goswami, Rajiv, E-mail: rajiv@ipr.res.in; Artaud, Jean-François; Imbeaux, Frédéric [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar—382428 (India)

    2014-07-15T23:59:59.000Z

    The plasma scrape-off layer (SOL) in a tokamak is characterized by ion flow down a long narrow flux tube terminating on a solid surface. The ion flow velocity along a magnetic field line can be equal to or greater than sonic at the entrance of a Debye sheath or upstream in the presheath. This paper presents a numerical study of the transition between subsonic and supersonics flows. A quasineutral one-dimensional (1D) fluid code has been used for modeling of plasma transport in the SOL along magnetic field lines, both in steady state and under transient conditions. The model uses coupled equations for continuity, momentum, and energy balance with ionization, radiation, charge exchange, and recombination processes. The recycled neutrals are described in the diffusion approximation. Standard Bohm sheath criterion is used as boundary conditions at the material surface. Three conditions conducive for the generation of supersonic flows in SOL plasmas have been explored. It is found that in steady state high (attached) and low (detached) divertor temperatures cases, the role of particle, momentum, and energy loss is critical. For attached case, the appearance of shock waves in the divertor region if the incoming plasma flow is supersonic and its effect on impurity retention is presented. In the third case, plasma expansion along the magnetic field can yield time-dependent supersonic solutions in the quasineutral rarefaction wave. Such situations can arise in the parallel transport of intermittent structures such as blobs and edge localized mode filaments along field lines.

  20. Anisotropic collective flow of a Lorentz gas

    E-Print Network [OSTI]

    Nicolas Borghini; Clement Gombeaud

    2011-06-30T23:59:59.000Z

    Analytical results for the anisotropic collective flow of a Lorentz gas of massless particles scattering on fixed centres are presented.

  1. Building up the elliptic flow: analytical insights

    E-Print Network [OSTI]

    Yoshitaka Hatta; Bo-Wen Xiao

    2014-07-15T23:59:59.000Z

    In this paper, we present a fully analytical description of the early-stage formation of elliptic flow in relativistic viscous hydrodynamics. We first construct an elliptic deformation of Gubser flow which is a boost invariant solution of the Navier-Stokes equation with a nontrivial transverse profile. We then analytically calculate the momentum anisotropy of the flow as a function of time and discuss the connection with the empirical formula by Bhalerao {\\it et al.} regarding the viscosity dependence of elliptic flow.

  2. Geothermal Heat Flow and Existing Geothermal Plants | Department...

    Energy Savers [EERE]

    Geothermal Heat Flow and Existing Geothermal Plants Geothermal Heat Flow and Existing Geothermal Plants Geothermal Heat Flow and Existing Plants With plants in development. Click...

  3. annular vertical flow: Topics by E-print Network

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

    of the polymer solution only. The linear stability analysis of the flow in the short-wave approximation captures quantitatively the flow diagram. Surprisingly, unstable flows...

  4. Effects of flow cell design on charge percolation and storage...

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

    Electrochemical flow capacitor Energy storage Flow battery Flowable electrode Supercapacitor a b s t r a c t The electrochemical flow capacitor (EFC) is an electrical energy...

  5. Thermal/chemical degradation of ceramic cross-flow filter materials

    SciTech Connect (OSTI)

    Alvin, M.A.; Lane, J.E.; Lippert, T.E.

    1989-11-01T23:59:59.000Z

    This report summarizes the 14-month, Phase 1 effort conducted by Westinghouse on the Thermal/Chemical Degradation of Ceramic Cross-Flow Filter Materials program. In Phase 1 expected filter process conditions were identified for a fixed-bed, fluid-bed, and entrained-bed gasification, direct coal fired turbine, and pressurized fluidized-bed combustion system. Ceramic cross-flow filter materials were also selected, procured, and subjected to chemical and physical characterization. The stability of each of the ceramic cross-flow materials was assessed in terms of potential reactions or phase change as a result of process temperature, and effluent gas compositions containing alkali and fines. In addition chemical and physical characterization was conducted on cross-flow filters that were exposed to the METC fluid-bed gasifier and the New York University pressurized fluidized-bed combustor. Long-term high temperature degradation mechanisms were proposed for each ceramic cross-flow material at process operating conditions. An experimental bench-scale test program is recommended to be conducted in Phase 2, generating data that support the proposed cross-flow filter material thermal/chemical degradation mechanisms. Papers on the individual subtasks have been processed separately for inclusion on the data base.

  6. PROBABILISTIC SIMULATION OF SUBSURFACE FLUID FLOW: A STUDY USING A NUMERICAL SCHEME

    SciTech Connect (OSTI)

    Buscheck, Timothy Eric

    1980-03-01T23:59:59.000Z

    There has been an increasing interest in probabilistic modeling of hydrogeologic systems. The classical approach to groundwater modeling has been deterministic in nature, where individual layers and formations are assumed to be uniformly homogeneous. Even in the case of complex heterogeneous systems, the heterogeneities describe the differences in parameter values between various layers, but not within any individual layer. In a deterministic model a single-number is assigned to each hydrogeologic parameter, given a particular scale of interest. However, physically there is no such entity as a truly uniform and homogeneous unit. Single-number representations or deterministic predictions are subject to uncertainties. The approach used in this work models such uncertainties with probabilistic parameters. The resulting statistical distributions of output variables are analyzed. A numerical algorithm, based on axiomatic principles of probability theory, performs arithmetic operations between probability distributions. Two subroutines are developed from the algorithm and incorporated into the computer program TERZAGI, which solves groundwater flow problems in saturated, multi-dimensional systems. The probabilistic computer program is given the name, PROGRES. The algorithm has been applied to study the following problems: one-dimensional flow through homogeneous media, steady-state and transient flow conditions, one-dimensional flow through heterogeneous media, steady-state and transient flow conditions, and two-dimensional steady-stte flow through heterogeneous media. The results are compared with those available in the literature.

  7. Application of a geocentrifuge and sterolithographically fabricated apertures to multiphase flow in complex fracture apertures.

    SciTech Connect (OSTI)

    Glenn E. McCreery; Robert D. Stedtfeld; Alan T. Stadler; Daphne L. Stoner; Paul Meakin

    2005-09-01T23:59:59.000Z

    A geotechnical centrifuge was used to investigate unsaturated multiphase fluid flow in synthetic fracture apertures under a variety of flow conditions. The geocentrifuge subjected the fluids to centrifugal forces allowing the Bond number to be systematically changed without adjusting the fracture aperture of the fluids. The fracture models were based on the concept that surfaces generated by the fracture of brittle geomaterials have a self-affine fractal geometry. The synthetic fracture surfaces were fabricated from a transparent epoxy photopolymer using sterolithography, and fluid flow through the transparent fracture models was monitored by an optical image acquisition system. Aperture widths were chosen to be representative of the wide range of geological fractures in the vesicular basalt that lies beneath the Idaho Nation Laboratory (INL). Transitions between different flow regimes were observed as the acceleration was changed under constant flow conditions. The experiments showed the transition between straight and meandering rivulets in smooth walled apertures (aperture width = 0.508 mm), the dependence of the rivulet width on acceleration in rough walled fracture apertures (average aperture width = 0.25 mm), unstable meandering flow in rough walled apertures at high acceleration (20g) and the narrowing of the wetted region with increasing acceleration during the penetration of water into an aperture filled with wetted particles (0.875 mm diameter glass spheres).

  8. Direct numerical simulation of turbulent reacting flows

    SciTech Connect (OSTI)

    Chen, J.H. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01T23:59:59.000Z

    The development of turbulent combustion models that reflect some of the most important characteristics of turbulent reacting flows requires knowledge about the behavior of key quantities in well defined combustion regimes. In turbulent flames, the coupling between the turbulence and the chemistry is so strong in certain regimes that is is very difficult to isolate the role played by one individual phenomenon. Direct numerical simulation (DNS) is an extremely useful tool to study in detail the turbulence-chemistry interactions in certain well defined regimes. Globally, non-premixed flames are controlled by two limiting cases: the fast chemistry limit, where the turbulent fluctuations. In between these two limits, finite-rate chemical effects are important and the turbulence interacts strongly with the chemical processes. This regime is important because industrial burners operate in regimes in which, locally the flame undergoes extinction, or is at least in some nonequilibrium condition. Furthermore, these nonequilibrium conditions strongly influence the production of pollutants. To quantify the finite-rate chemistry effect, direct numerical simulations are performed to study the interaction between an initially laminar non-premixed flame and a three-dimensional field of homogeneous isotropic decaying turbulence. Emphasis is placed on the dynamics of extinction and on transient effects on the fine scale mixing process. Differential molecular diffusion among species is also examined with this approach, both for nonreacting and reacting situations. To address the problem of large-scale mixing and to examine the effects of mean shear, efforts are underway to perform large eddy simulations of round three-dimensional jets.

  9. Organized Oscillations of Initially-Turbulent Flow Past a Cavity

    SciTech Connect (OSTI)

    J.C. Lin; D. Rockwell

    2002-09-17T23:59:59.000Z

    Flow past an open cavity is known to give rise to self-sustained oscillations in a wide variety of configurations, including slotted-wall, wind and water tunnels, slotted flumes, bellows-type pipe geometries, high-head gates and gate slots, aircraft components and internal piping systems. These cavity-type oscillations are the origin of coherent and broadband sources of noise and, if the structure is sufficiently flexible, flow-induced vibration as well. Moreover, depending upon the state of the cavity oscillation, substantial alterations of the mean drag may be induced. In the following, the state of knowledge of flow past cavities, based primarily on laminar inflow conditions, is described within a framework based on the flow physics. Then, the major unresolved issues for this class of flows will be delineated. Self-excited cavity oscillations have generic features, which are assessed in detail in the reviews of Rockwell and Naudascher, Rockwell, Howe and Rockwell. These features, which are illustrated in the schematic of Figure 1, are: (i) interaction of a vorticity concentration(s) with the downstream corner, (ii) upstream influence from this corner interaction to the sensitive region of the shear layer formed from the upstream corner of the cavity; (iii) conversion of the upstream influence arriving at this location to a fluctuation in the separating shear layer; and (iv) amplification of this fluctuation in the shear layer as it develops in the streamwise direction. In view of the fact that inflow shear-layer in the present investigation is fully turbulent, item (iv) is of particular interest. It is generally recognized, at least for laminar conditions at separation from the leading-corner of the cavity, that the disturbance growth in the shear layer can be described using concepts of linearized, inviscid stability theory, as shown by Rockwell, Sarohia, and Knisely and Rockwell. As demonstrated by Knisely and Rockwell, on the basis of experiments interpreted with the aid of linearized theory, not only the fundamental component of the shear layer instability may be present, but a number of additional, primarily lower frequency components can exist as well. In fact, the magnitude of these components can be of the same order as the fundamental component. These issues have not been addressed for the case of a fully-turbulent in-flow and its separation from the leading corner of the cavity.

  10. Zonal Flow as Pattern Formation

    E-Print Network [OSTI]

    Parker, Jeffrey B

    2015-01-01T23:59:59.000Z

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

  11. Supercritical flow in rectangular expansions

    E-Print Network [OSTI]

    Walsh, Peter.

    1968-01-01T23:59:59.000Z

    is the differential element of length along C. Equations [7] and [8] may be rearranged in the following manner: du = ? dx + ? dy du Qu gx ay dv = ? dx + ? dy 3v av 'bx Py [10] where du = (3u/Bs)ds, dv = (pv/3s)ds, dx = (3x/as)ds, and dy = (s y/p s) ds. The four... common tangent A P . Since a disturbance travels from A to P in n 1 the same time that a particle moves from A to A it follows that n A P = sin S =? A A v 1 n where I9 is the angle between the shock wave and the direction of flow. When the flow...

  12. Characterizing flow fluctuations with moments

    E-Print Network [OSTI]

    Rajeev S. Bhalerao; Jean-Yves Ollitrault; Subrata Pal

    2015-01-22T23:59:59.000Z

    We present a complete set of multiparticle correlation observables for ultrarelativistic heavy-ion collisions. These include moments of the distribution of the anisotropic flow in a single harmonic, and also mixed moments, which contain the information on correlations between event planes of different harmonics. We explain how all these moments can be measured using just two symmetric subevents separated by a rapidity gap. This presents a multi-pronged probe of the physics of flow fluctuations. For instance, it allows to test the hypothesis that event-plane correlations are generated by non-linear hydrodynamic response. We illustrate the method with simulations of events in A MultiPhase Transport (AMPT) model.

  13. Gas flow in barred potentials

    E-Print Network [OSTI]

    Sormani, Mattia C; Magorrian, John

    2015-01-01T23:59:59.000Z

    We use a Cartesian grid to simulate the flow of gas in a barred Galactic potential and investigate the effects of varying the sound speed in the gas and the resolution of the grid. For all sound speeds and resolutions, streamlines closely follow closed orbits at large and small radii. At intermediate radii shocks arise and the streamlines shift between two families of closed orbits. The point at which the shocks appear and the streamlines shift between orbit families depends strongly on sound speed and resolution. For sufficiently large values of these two parameters, the transfer happens at the cusped orbit as hypothesised by Binney et al. over two decades ago. For sufficiently high resolutions the flow downstream of the shocks becomes unsteady. If this unsteadiness is physical, as appears to be the case, it provides a promising explanation for the asymmetry in the observed distribution of CO.

  14. Cascade redox flow battery systems

    DOE Patents [OSTI]

    Horne, Craig R.; Kinoshita, Kim; Hickey, Darren B.; Sha, Jay E.; Bose, Deepak

    2014-07-22T23:59:59.000Z

    A reduction/oxidation ("redox") flow battery system includes a series of electrochemical cells arranged in a cascade, whereby liquid electrolyte reacts in a first electrochemical cell (or group of cells) before being directed into a second cell (or group of cells) where it reacts before being directed to subsequent cells. The cascade includes 2 to n stages, each stage having one or more electrochemical cells. During a charge reaction, electrolyte entering a first stage will have a lower state-of-charge than electrolyte entering the nth stage. In some embodiments, cell components and/or characteristics may be configured based on a state-of-charge of electrolytes expected at each cascade stage. Such engineered cascades provide redox flow battery systems with higher energy efficiency over a broader range of current density than prior art arrangements.

  15. General Message Flow Modulator Ann E. Siebert

    E-Print Network [OSTI]

    Boyer, Robert Stephen

    General Message Flow Modulator Ann E. Siebert Donald I. Good Technical Report #42 March 1984 (512) 471-1901 #12;Abstract The general message flow modulator is a high level design of a family of mechanisms for controlling the flow of messages from a source to a destination. This family of mechanisms has

  16. Flow and Plate Motion in Compressor Valves

    E-Print Network [OSTI]

    Twente, Universiteit

    Flow and Plate Motion in Compressor Valves #12;Flow and Plate Motion in Compressor Valves R.A. Habing Cover Image: 4-stage reciprocating compressor system, Courtesy of Ariel Corporation Thesis.A. Habing, Enschede, The Netherlands #12;FLOW AND PLATE MOTION IN COMPRESSOR VALVES PROEFSCHRIFT ter

  17. Secured Information Flow for Asynchronous Sequential Processes

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    Paris-Sud XI, Université de

    Secured Information Flow for Asynchronous Sequential Processes Isabelle Attali, Denis Caromel for unauthorized information flows. As a final result, all authorized communication paths are secure: no disclosure a new issue in data confidentiality: authorization of secured information flow transiting (by the mean

  18. Flow Duration Curve Load Duration Curve

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    #12;Flow Duration Curve Load Duration Curve #12;1. Develop Flow Duration Curve 2. Estimate load given flow and concentration data--select appropriate conversion factors 3. Develop Load Duration Curve 4. Plot observed data with Load Duration Curve #12;What are they? How do you make one? #12;Describes

  19. Optimal Power Flow Incorporating Voltage Collapse Constraints

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    Optimal Power Flow Incorporating Voltage Collapse Constraints William Rosehart Claudio Ca on the current operating con- ditions is presented. Second, an Optimal Power Flow formulation that incorporates: Voltage Collapse, Optimal Power Flow, Bifur- cations. I. Introduction As open-access market principles

  20. (Preview Draft) Chapter 3. Stocks and Flows

    E-Print Network [OSTI]

    Ford, Andrew

    the state over time. It will take some time for the flows to have their effect on the stocks, so the stocks(Preview Draft) Chapter 3. Stocks and Flows: The Building Blocks of System Dynamics Models The best way to construct a model is to start with the stocks, add the flows and then use converters to explain