Sample records for gas flow patterns

  1. Flow Patterns, Void Fraction and Pressure Drop in Gas-Liquid Two

    E-Print Network [OSTI]

    Ghajar, Afshin J.

    and simultaneous transportation of oil and natural gas from remote extraction locations to the processing units#12;Chapter 4 Flow Patterns, Void Fraction and Pressure Drop in Gas-Liquid Two Phase Flow in gas-liquid two phase flow. The flow structure of different flow patterns observed in gas-liquid two

  2. Gasliquid two-phase flow patterns in a miniature square channel with a gas permeable sidewall

    E-Print Network [OSTI]

    Zhao, Tianshou

    configuration considered in this work, the stratified flow and wavy flow were not found in horizontal flow by a mono small-gas-bubble layer existing adjacent to the surface of the permeable sidewall in vertical downward flows; and Kosterin [5] and Brigham et al. [6] discussed flow patterns in inclined

  3. Solid oxide fuel cell having compound cross flow gas patterns

    DOE Patents [OSTI]

    Fraioli, Anthony V. (Hawthorn Woods, IL)

    1985-01-01T23:59:59.000Z

    A core construction for a fuel cell is disclosed having both parallel and cross flow passageways for the fuel and the oxidant gases. Each core passageway is defined by electrolyte and interconnect walls. Each electrolyte wall consists of cathode and anode materials sandwiching an electrolyte material. Each interconnect wall is formed as a sheet of inert support material having therein spaced small plugs of interconnect material, where cathode and anode materials are formed as layers on opposite sides of each sheet and are electrically connected together by the interconnect material plugs. Each interconnect wall in a wavy shape is connected along spaced generally parallel line-like contact areas between corresponding spaced pairs of generally parallel electrolyte walls, operable to define one tier of generally parallel flow passageways for the fuel and oxidant gases. Alternate tiers are arranged to have the passageways disposed normal to one another. Solid mechanical connection of the interconnect walls of adjacent tiers to the opposite sides of the common electrolyte wall therebetween is only at spaced point-like contact areas, 90 where the previously mentioned line-like contact areas cross one another.

  4. Solid oxide fuel cell having compound cross flow gas patterns

    DOE Patents [OSTI]

    Fraioli, A.V.

    1983-10-12T23:59:59.000Z

    A core construction for a fuel cell is disclosed having both parallel and cross flow passageways for the fuel and the oxidant gases. Each core passageway is defined by electrolyte and interconnect walls. Each electrolyte wall consists of cathode and anode materials sandwiching an electrolyte material. Each interconnect wall is formed as a sheet of inert support material having therein spaced small plugs of interconnect material, where cathode and anode materials are formed as layers on opposite sides of each sheet and are electrically connected together by the interconnect material plugs. Each interconnect wall in a wavy shape is connected along spaced generally parallel line-like contact areas between corresponding spaced pairs of generally parallel electrolyte walls, operable to define one tier of generally parallel flow passageways for the fuel and oxidant gases. Alternate tiers are arranged to have the passageways disposed normal to one another. Solid mechanical connection of the interconnect walls of adjacent tiers to the opposite sides of the common electrolyte wall therebetween is only at spaced point-like contact areas, 90 where the previously mentioned line-like contact areas cross one another.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Laser cross-flow gas system

    DOE Patents [OSTI]

    Duncan, D.B.

    1992-11-24T23:59:59.000Z

    A method and laser apparatus are disclosed which provide for a cross-flow of gas near one end of a laser discharge tube. The cross-flow of gas causes a concentration gradient which affects diffusion of contaminants in the discharge tube towards the cross-flow of the gas, which contaminants are then withdrawn from the discharge tube. 1 figure.

  12. 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.

  13. Oil and Gas CDT Coupled flow of water and gas

    E-Print Network [OSTI]

    Henderson, Gideon

    Oil and Gas CDT Coupled flow of water and gas during hydraulic fracture in shale The University of Oxford http://www.earth.ox.ac.uk/people/profiles/academic/joec Key Words Shale gas, hydraulic fracture, groundwater contamination, transport in porous media Overview Recovery of natural gas from mudstone (shale

  14. 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.

  15. Estimating Major and Minor Natural Fracture Patterns in Gas

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    Estimating Major and Minor Natural Fracture Patterns in Gas Shales Using Production Data Razi Identification of infill drilling locations has been challenging with mixed results in gas shales. Natural fractures are the main source of permeability in gas shales. Natural fracture patterns in shale has a random

  16. 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.

  17. Gas flows and bars in galaxies

    E-Print Network [OSTI]

    F. Combes

    2006-08-29T23:59:59.000Z

    Dynamical evolution of spiral galaxies is strongly dependent on non-axisymmetric patterns that develop from gravitational instabilities, either spontaneously or externally triggered. Some evolutionary sequences are described through which a galaxy could possibly concentrate mass and build bulges, how external gas accretion from cosmic filaments could be funneled to the galaxy disks, and intermittently driven to the galaxy center, to form nuclear starbursts and fuel an active nucleus. The frequency of both bars and lopsidedness can be used to constrain the gas accretion rate.

  18. NIST Measurement Services: Natural Gas Flow Calibration Service (NGFCS)

    E-Print Network [OSTI]

    NIST Measurement Services: Natural Gas Flow Calibration Service (NGFCS) NIST Special Publication of Standards and Technology #12;i Table of Contents for the Natural Gas Flowmeter Calibration Service (NGFCS;1 Abstract This document describes NIST's high pressure natural gas flow calibration service (NGFCS). Flow

  19. Modification of plasma flows with gas puff in the scrape-off layer of ADITYA tokamak

    SciTech Connect (OSTI)

    Sangwan, Deepak; Jha, Ratneshwar; Brotankova, Jana; Gopalkrishna, M. V. [Institute for Plasma Research, Gandhinagar 382428 (India)] [Institute for Plasma Research, Gandhinagar 382428 (India)

    2013-06-15T23:59:59.000Z

    The parallel Mach numbers are measured at three locations in the scrape-off layer (SOL) plasma of ADITYA tokamak by using Mach probes. The flow pattern is constructed from these measurements and the modification of flow pattern is observed by introducing a small puff of working gas. In the normal discharge, there is an indication of shell structure in the SOL plasma flows, which is removed during the gas puff. The plasma parameters, particle flux and Reynolds stress are also measured in the normal discharge and in the discharge with gas puff. It is observed that Reynolds stress and Mach number are coupled in the near SOL region and decoupled in the far SOL region. The coupling in the near SOL region gets washed away during the gas puff.

  20. 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.

  1. Classification of Two-Phase Flow Patterns by Ultrasonic Sensing

    E-Print Network [OSTI]

    Ray, Asok

    (e.g., petrochemical processes and nuclear power plants). This concept of flow pattern classification are critical for design, analysis, and operation in a variety of industries such as petrochemical processes

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

    E-Print Network [OSTI]

    Tsunehiro Kobayashi

    2003-02-20T23:59:59.000Z

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

  3. Gas Flowmeter Calibrations with the Working Gas Flow Standard NIST Special Publication 250-80

    E-Print Network [OSTI]

    Gas Flowmeter Calibrations with the Working Gas Flow Standard NIST Special Publication 250-80 John of Standards and Technology U. S. Department of Commerce #12;ii Table of Contents Gas Flowmeter Calibrations with the Working Gas Flow Standard .......................... i Abstract

  4. Multiphase imaging of gas flow in a nanoporous material usingremote detection NMR

    SciTech Connect (OSTI)

    Harel, Elad; Granwehr, Josef; Seeley, Juliette A.; Pines, Alex

    2005-10-03T23:59:59.000Z

    Pore structure and connectivity determine how microstructured materials perform in applications such as catalysis, fluid storage and transport, filtering, or as reactors. We report a model study on silica aerogel using a recently introduced time-of-flight (TOF) magnetic resonance imaging technique to characterize the flow field and elucidate the effects of heterogeneities in the pore structure on gas flow and dispersion with Xe-129 as the gas-phase sensor. The observed chemical shift allows the separate visualization of unrestricted xenon and xenon confined in the pores of the aerogel. The asymmetrical nature of the dispersion pattern alludes to the existence of a stationary and a flow regime in the aerogel. An exchange time constant is determined to characterize the gas transfer between them. As a general methodology, this technique provides new insights into the dynamics of flow in porous media where multiple phases or chemical species may be present.

  5. Tritium flow through a non-symmetrical source. Simulation of gas flow through an injection hole

    E-Print Network [OSTI]

    Sharipov, Felix

    Tritium flow through a non-symmetrical source. Simulation of gas flow through an injection hole of source in injection rarefaction parameter µ0 viscosity of tritium at T0 Pa s 2 #12;Ll = 5074.5 Lr = 5007

  6. Gas flow driven by thermal creep in dusty plasma

    SciTech Connect (OSTI)

    Flanagan, T. M.; Goree, J. [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States)

    2009-10-15T23:59:59.000Z

    Thermal creep flow (TCF) is a flow of gas driven by a temperature gradient along a solid boundary. Here, TCF is demonstrated experimentally in a dusty plasma. Stripes on a glass box are heated by laser beam absorption, leading to both TCF and a thermophoretic force. The design of the experiment allows isolating the effect of TCF. A stirring motion of the dust particle suspension is observed. By eliminating all other explanations for this motion, we conclude that TCF at the boundary couples by drag to the bulk gas, causing the bulk gas to flow, thereby stirring the suspension of dust particles. This result provides an experimental verification, for the field of fluid mechanics, that TCF in the slip-flow regime causes steady-state gas flow in a confined volume.

  7. 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.

  8. HERA-B Gas Systems The gas mixture, the gas volume of the corresponding detector and the required gas flow are given. All detectors are operating at nominal

    E-Print Network [OSTI]

    HERA-B Gas Systems The gas mixture, the gas volume of the corresponding detector and the required gas flow are given. All detectors are operating at nominal pressure within a given tolerance p. The pipes connecting the external gas hut with the third floor of the electronics trailer are listed on page

  9. Comparison of electrical capacitance tomography and gamma densitometer measurement in viscous oil-gas flows

    SciTech Connect (OSTI)

    Archibong Eso, A.; Zhao, Yabin; Yeung, Hoi [Department of Offshore Process and Energy Systems Engineering, Cranfield University, Cranfield (United Kingdom)

    2014-04-11T23:59:59.000Z

    Multiphase flow is a common occurrence in industries such as nuclear, process, oil and gas, food and chemical. A prior knowledge of its features and characteristics is essential in the design, control and management of such processes due to its complex nature. Electrical Capacitance Tomography (ECT) and Gamma Densitometer (Gamma) are two promising approaches for multiphase visualization and characterization in process industries. In two phase oil and gas flow, ECT and Gamma are used in multiphase flow monitoring techniques due to their inherent simplicity, robustness, and an ability to withstand wide range of operational temperatures and pressures. High viscous oil (viscosity > 100 cP) is of interest because of its huge reserves, technological advances in its production and unlike conventional oil (oil viscosity < 100 cP) and gas flows where ECT and Gamma have been previously used, high viscous oil and gas flows comes with certain associated concerns which include; increased entrainment of gas bubbles dispersed in oil, shorter and more frequent slugs as well as oil film coatings on the walls of flowing conduits. This study aims to determine the suitability of both devices in the visualization and characterization of high-viscous oil and gas flow. Static tests are performed with both devices and liquid holdup measurements are obtained. Dynamic experiments were also conducted in a 1 and 3 inch facility at Cranfield University with a range of nominal viscosities (1000, 3000 and 7500 cP). Plug, slug and wavy annular flow patterns were identified by means of Probability Mass Function and time series analysis of the data acquired from Gamma and ECT devices with high speed camera used to validate the results. Measured Liquid holdups for both devices were also compared.

  10. Gas Bubble Formation in Stagnant and Flowing Mercury

    SciTech Connect (OSTI)

    Wendel, Mark W [ORNL] [ORNL; Abdou, Ashraf A [ORNL] [ORNL; Riemer, Bernie [ORNL] [ORNL; Felde, David K [ORNL] [ORNL

    2007-01-01T23:59:59.000Z

    Investigations in the area of two-phase flow at the Oak Ridge National Laboratory's (ORNL) Spallation Neutron Source (SNS) facility are progressing. It is expected that the target vessel lifetime could be extended by introducing gas into the liquid mercury target. As part of an effort to validate the two-phase computational fluid dynamics (CFD) model, simulations and experiments of gas injection in stagnant and flowing mercury have been completed. The volume of fluid (VOF) method as implemented in ANSYS-CFX, was used to simulate the unsteady two-phase flow of gas injection into stagnant mercury. Bubbles produced at the upwards-oriented vertical gas injector were measured with proton radiography at the Los Alamos Neutron Science Center. The comparison of the CFD results to the radiographic images shows good agreement for bubble sizes and shapes at various stages of the bubble growth, detachment, and gravitational rise. Although several gas flows were measured, this paper focuses on the case with a gas flow rate of 8 cc/min through the 100-micron-diameter injector needle. The acoustic waves emitted due to the detachment of the bubble and during subsequent bubble oscillations were recorded with a microphone, providing a precise measurement of the bubble sizes. As the mercury flow rate increases, the drag force causes earlier bubble detachment and therefore smaller bubbles.

  11. Micromachined thin-film gas flow sensor for microchemical reactors

    E-Print Network [OSTI]

    Besser, Ronald S.

    Micromachined thin-film gas flow sensor for microchemical reactors W C Shin and R S Besser New applications not practical before such as highly compact, non-invasive pressure sensors, accelerometers and gas power consumption, fast response, and low-cost batch production [1-4]. Spurred by the development

  12. Coal Particle Flow Patterns for O2 Enriched, Low NOx Burners

    SciTech Connect (OSTI)

    Jennifer Sinclair Curtis

    2005-08-01T23:59:59.000Z

    This project involved a systematic investigation examining the effect of near-flame burner aerodynamics on standoff distance and stability of turbulent diffusion flames and the resultant NO{sub x} emissions from actual pulverized coal diffusion flames. Specifically, the scope of the project was to understand how changes in near-flame aerodynamics and transport air oxygen partial pressure can influence flame attachment and coal ignition, two properties essential to proper operation of low NO{sub x} burners. Results from this investigation utilized a new 2M tall, 0.5m in diameter combustor designed to evaluate near-flame combustion aerodynamics in terms of transport air oxygen partial pressure (Po{sub 2}), coal fines content, primary fuel and secondary air velocities, and furnace wall temperature furnish insight into fundamental processes that occur during combustion of pulverized coal in practical systems. Complementary cold flow studies were conducted in a geometrically similar chamber to analyze the detailed motion of the gas and particles using laser Doppler velocimetry. This final technical report summarizes the key findings from our investigation into coal particle flow patterns in burners. Specifically, we focused on the effects of oxygen enrichment, the effect of fines, and the effect of the nozzle velocity ratio on the resulting flow patterns. In the cold flow studies, detailed measurements using laser Doppler velocimetry (LDV) were made to determine the details of the flow. In the hot flow studies, observations of flame stability and measurements of NO{sub x} were made to determine the effects of the flow patterns on burner operation.

  13. Progress in Creating Stabilized Gas Layers in Flowing Liquid Mercury

    SciTech Connect (OSTI)

    Wendel, Mark W [ORNL; Felde, David K [ORNL; Riemer, Bernie [ORNL; Abdou, Ashraf A [ORNL; D'Urso, Brian R [ORNL; West, David L [ORNL

    2009-01-01T23:59:59.000Z

    The Spallation Neutron Source (SNS) facility in Oak Ridge, Tennessee uses a liquid mercury target that is bombarded with protons to produce a pulsed neutron beam for materials research and development. In order to mitigate expected cavitation damage erosion (CDE) of the containment vessel, a two-phase flow arrangement of the target has been proposed and was earlier proven to be effective in significantly reducing CDE in non-prototypical target bodies. This arrangement involves covering the beam "window", through which the high-energy proton beam passes, with a protective layer of gas. The difficulty lies in establishing a stable gas/liquid interface that is oriented vertically with the window and holds up to the strong buoyancy force and the turbulent mercury flow field. Three approaches to establishing the gas wall have been investigated in isothermal mercury/gas testing on a prototypical geometry and flow: (1) free gas layer approach, (2) porous wall approach, and (3) surface-modified approach. The latter two of these approaches show success in that a stabilized gas layer is produced. Both of these successful approaches capitalize on the high surface energy of liquid mercury by increasing the surface area of the solid wall, thus increasing gas hold up at the wall. In this paper, a summary of these experiments and findings is presented as well as a description of the path forward toward incorporating the stabilized gas layer approach into a feasible gas/mercury SNS target design.

  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. GLOBAL OPTIMIZATION OF MULTIPHASE FLOW NETWORKS IN OIL AND GAS PRODUCTION SYSTEMS

    E-Print Network [OSTI]

    Johansen, Tor Arne

    1 GLOBAL OPTIMIZATION OF MULTIPHASE FLOW NETWORKS IN OIL AND GAS PRODUCTION SYSTEMS MSc. Hans in an oil production system is developed. Each well may be manipulated by injecting lift gas and adjusting in the maximum oil flow rate, water flow rate, liquid flow rate, and gas flow rate. The wells may also

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

    SciTech Connect (OSTI)

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

    2001-09-04T23:59:59.000Z

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

  17. Hot gas cross flow filtering module

    DOE Patents [OSTI]

    Lippert, Thomas E. (Murrysville Boro, PA); Ciliberti, David F. (Murrysville Boro, PA)

    1988-01-01T23:59:59.000Z

    A filter module for use in filtering particulates from a high temperature gas has a central gas duct and at least one horizontally extending support mount affixed to the duct. The support mount supports a filter element thereon and has a chamber therein, which communicates with an inner space of the duct through an opening in the wall of the duct, and which communicates with the clean gas face of the filter element. The filter element is secured to the support mount over an opening in the top wall of the support mount, with releasable securement provided to enable replacement of the filter element when desired. Ceramic springs may be used in connection with the filter module either to secure a filter element to a support mount or to prevent delamination of the filter element during blowback.

  18. Device for measuring the flow of a gas containing particulates

    SciTech Connect (OSTI)

    Gordon, R.G.; Hofer, P.H.

    1991-01-08T23:59:59.000Z

    This patent describes an apparatus for continuously measuring the flow of a gas containing entrained particulates. It comprises: a flow channel, through which the gas flows; an orifice disposed within the flow channel, including at least a first surface and a second surface; means for causing the first surface and second surface independently to move in directions perpendicular to lines normal to the surfaces; scraping means, for intimately contacting at least a portion of the first surface and of the second surface, at all times while the surfaces are moving, whereby particulates which adhere to the first and second surfaces are removed by the movement of the surfaces past the scraping means; pressure taps, positioned so as to communicate with the flow channel upstream and downstream from the orifice, the pressure taps additionally in communication with pressure-measuring means, for measuring the pressure differential in the flow channel resulting from the passage of the gas through the orifice; and thermophoretic heaters, positioned so as to heat the gas within the pressure taps, and thereby excluding particulates therefrom.

  19. Rarefied gas flow in a rectangular enclosure induced by non-isothermal walls

    SciTech Connect (OSTI)

    Vargas, Manuel; Tatsios, Giorgos; Valougeorgis, Dimitris, E-mail: diva@mie.uth.gr [Department of Mechanical Engineering, University of Thessaly, 38334 Volos (Greece)] [Department of Mechanical Engineering, University of Thessaly, 38334 Volos (Greece); Stefanov, Stefan [Institute of Mechanics, Bulgarian Academy of Sciences, Sofia (Bulgaria)] [Institute of Mechanics, Bulgarian Academy of Sciences, Sofia (Bulgaria)

    2014-05-15T23:59:59.000Z

    The flow of a rarefied gas in a rectangular enclosure due to the non-isothermal walls with no synergetic contributions from external force fields is investigated. The top and bottom walls are maintained at constant but different temperatures and along the lateral walls a linear temperature profile is assumed. Modeling is based on the direct numerical solution of the Shakhov kinetic equation and the Direct Simulation Monte Carlo (DSMC) method. Solving the problem both deterministically and stochastically allows a systematic comparison and verification of the results as well as the exploitation of the numerical advantages of each approach in the investigation of the involved flow and heat transfer phenomena. The thermally induced flow is simulated in terms of three dimensionless parameters characterizing the problem, namely, the reference Knudsen number, the temperature ratio of the bottom over the top plates, and the enclosure aspect ratio. Their effect on the flow configuration and bulk quantities is thoroughly examined. Along the side walls, the gas flows at small Knudsen numbers from cold-to-hot, while as the Knudsen number is increased the gas flows from hot-to-cold and the thermally induced flow configuration becomes more complex. These flow patterns with the hot-to-cold flow to be extended to the whole length of the non-isothermal side walls may exist even at small temperature differences and then, they are enhanced as the temperature difference between the top and bottom plates is increased. The cavity aspect ratio also influences this flow configuration and the hot-to-cold flow is becoming more dominant as the depth compared to the width of the cavity is increased. To further analyze the flow patterns a novel solution decomposition into ballistic and collision parts is introduced. This is achieved by accordingly modifying the indexing process of the typical DSMC algorithm. The contribution of each part of the solution is separately examined and a physical interpretation of the flow configuration, including the hot-to-cold flow close to the side walls, in the whole range of the Knudsen number is provided.

  20. Numerical simulations of the Macondo well blowout reveal strong control of oil flow by reservoir permeability and exsolution of gas

    E-Print Network [OSTI]

    Oldenburg, C.M.

    2013-01-01T23:59:59.000Z

    for estimates of the oil and gas flow rate from the Macondoteam and carried out oil and gas flow simulations using theoil-gas system. The flow of oil and gas was simulated using

  1. Turbine exhaust diffuser with region of reduced flow area and outer boundary gas flow

    DOE Patents [OSTI]

    Orosa, John

    2014-03-11T23:59:59.000Z

    An exhaust diffuser system and method for a turbine engine. The outer boundary may include a region in which the outer boundary extends radially inwardly toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. At least one gas jet is provided including a jet exit located on the outer boundary. The jet exit may discharge a flow of gas downstream substantially parallel to an inner surface of the outer boundary to direct a portion of the exhaust flow in the diffuser toward the outer boundary to effect a radially outward flow of at least a portion of the exhaust gas flow toward the outer boundary to balance an aerodynamic load between the outer and inner boundaries.

  2. Cold molecular gas in cooling flow clusters of galaxies

    E-Print Network [OSTI]

    P. Salome; F. Combes

    2003-09-10T23:59:59.000Z

    The results of a CO line survey in central cluster galaxies with cooling flows are presented. Cold molecular gas is detected with the IRAM 30m telescope, through CO(1-0) and CO(2-1) emission lines in 6-10 among 32 galaxies. The corresponding gas masses are between 3.10^8 and 4.10^10 Msol. These results are in agreement with recent CO detections by Edge (2001). A strong correlation between the CO emission and the Halpha luminosity is also confirmed. Cold gas exists in the center of cooling flow clusters and these detections may be interpreted as an evidence of the long searched very cold residual of the hot cooling gas.

  3. Microfluidic gas flow profiling using remote detection NMR

    SciTech Connect (OSTI)

    Hilty, Christian; McDonnell, Erin; Granwehr, Josef; Pierce,Kimberly; Han, Song-I Han; Pines, Alexander

    2005-05-06T23:59:59.000Z

    Miniaturized fluid handling devices have recently attracted considerable interest in many areas of science1. Such microfluidic chips perform a variety of functions, ranging from analysis of biological macromolecules2,3 to catalysis of reactions and sensing in the gas phase4,5. To enable precise fluid handling, accurate knowledge of the flow properties within these devices is important. Due to low Reynolds numbers, laminar flow is usually assumed. However, either by design or unintentionally, the flow characteristic in small channels is often altered, for example by surface interactions, viscous and diffusional effects, or electrical potentials. Therefore, its prediction is not always straight-forward6-8. Currently, most microfluidic flow measurements rely on optical detection of markers9,10, requiring the injection of tracers and transparent devices. Here, we show profiles of microfluidic gas flow in capillaries and chip devices obtained by NMR in the remote detection modality11,12. Through the transient measurement of dispersion13, NMR is well adaptable for non-invasive, yet sensitive determination of the flow field and provides a novel and potentially more powerful tool to profile flow in capillaries and miniaturized flow devices.

  4. craton, where the pattern matches that expected from the gas-hydrate model. Fur-

    E-Print Network [OSTI]

    Kilgard, Michael P.

    craton, where the pattern matches that expected from the gas-hydrate model. Fur- ther, values-lived changes in the carbon-isotopic composition of the ocean. But the gas-hydrate model avoids some

  5. Aerodynamics of Two Interfering Simple-Shape Bodies in Hypersonic Rarefied-Gas Flows

    E-Print Network [OSTI]

    Riabov, Vladimir V.

    ] for transition rarefied-gas flows. Supersonic, subsonic, and pressure-driven, low-speed flows in twoAerodynamics of Two Interfering Simple-Shape Bodies in Hypersonic Rarefied-Gas Flows Vladimir V. Riabov Rivier College, Nashua, New Hampshire, USA Abstract. Hypersonic rarefied-gas flows near two side

  6. Turbulent flow of gas in fractures

    E-Print Network [OSTI]

    Koh, Wong In

    1974-01-01T23:59:59.000Z

    sises of 40 - 60, 20 - 40 and 10 - 20 mesh and with varying concentration of proppants . The confining pressure was varied for each core up to $, 000 psi step by step. The proppant concentration in each fracture was varied up to a complete monolayer... an ovex'bux'den pressure of 4, 000 psi, the reduction in flow capaoity would vary from 86 $ to 76 4 with corresponding change of pressure dxop from 2, 000 psi to 7, 000 psi across a 320 ft long fractuxe. ACKHOWLEDGENEN% The author wishes to extend...

  7. Energy policy act transportation study: Interim report on natural gas flows and rates

    SciTech Connect (OSTI)

    NONE

    1995-11-17T23:59:59.000Z

    This report, Energy Policy Act Transportation Study: Interim Report on Natural Gas Flows and Rates, is the second in a series mandated by Title XIII, Section 1340, ``Establishment of Data Base and Study of Transportation Rates,`` of the Energy Policy Act of 1992 (P.L. 102--486). The first report Energy Policy Act Transportation Study: Availability of Data and Studies, was submitted to Congress in October 1993; it summarized data and studies that could be used to address the impact of legislative and regulatory actions on natural gas transportation rates and flow patterns. The current report presents an interim analysis of natural gas transportation rates and distribution patterns for the period from 1988 through 1994. A third and final report addressing the transportation rates and flows through 1997 is due to Congress in October 2000. This analysis relies on currently available data; no new data collection effort was undertaken. The need for the collection of additional data on transportation rates will be further addressed after this report, in consultation with the Congress, industry representatives, and in other public forums.

  8. Predicting enhanced mass flow rates in gas microchannels using nonkinetic models

    E-Print Network [OSTI]

    Dadzie, S. Kokou

    Different nonkinetic approaches are adopted in this paper towards theoretically predicting the experimentally observed phenomenon of enhanced mass flow rates accompanying pressure-driven rarefied gas flows through ...

  9. Pattern Of Shallow Ground Water Flow At Mount Princeton Hot Springs...

    Open Energy Info (EERE)

    Methods Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Pattern Of Shallow Ground Water Flow At Mount Princeton Hot Springs,...

  10. Pattern of shallow ground water flow at Mount Princeton Hot Springs...

    Open Energy Info (EERE)

    methods Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Pattern of shallow ground water flow at Mount Princeton Hot Springs,...

  11. Vaporization cooling for gas turbines, the return-flow cascade

    SciTech Connect (OSTI)

    Kerrebrock, J.L.; Stickler, D.B.

    2000-01-01T23:59:59.000Z

    A new paradigm for gas turbine design is treated, in which major elements of the hot section flow path are cooled by vaporization of a suitable two-phase coolant. This enables the blades to be maintained at nearly uniform temperature without detailed knowledge of the heat flux to the blades, and makes operation feasible at higher combustion temperatures using a wider range of materials than is possible in conventional gas turbines with air cooling. The new enabling technology for such cooling is the return-flow cascade, which extends to the rotating blades the heat flux capability and self-regulation usually associated with heat-pipe technology. In this paper the potential characteristics of gas turbines that use vaporization cooling are outlined briefly, but the principal emphasis is on the concept of the return-flow cascade. The concept is described and its characteristics are outlined. Experimental results are presented that confirm its conceptual validity and demonstrate its capability for blade cooling at heat fluxes representative of those required for high pressure ratio high temperature gas turbines.

  12. Enhanced thermal and gas flow performance in a three-way catalytic...

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

    thermal and gas flow performance in a three-way catalytic converter through use of insulation within the ceramic monolith Enhanced thermal and gas flow performance in a three-way...

  13. Recognising Visual Patterns to Communicate Gas Turbine Time-Series Data

    E-Print Network [OSTI]

    Reiter, Ehud

    Recognising Visual Patterns to Communicate Gas Turbine Time-Series Data Jin Yu, Jim Hunter, Ehud analogue channels are sampled once per second and archived by the Tiger system for monitoring gas turbines is the generation of textual summaries. We are developing a knowledge-based system to summarise such data in the gas

  14. Investigation of Swirl Flows Applied to the Oil and Gas Industry

    E-Print Network [OSTI]

    Ravuri Venkata Krish, Meher Surendra

    2010-01-16T23:59:59.000Z

    Understanding how swirl flows can be applied to processes in the oil and gas industry and how problems might hinder them, are the focus of this thesis. Three application areas were identified: wet gas metering, liquid loading in gas wells...

  15. Flammable gas interlock spoolpiece flow response test report

    SciTech Connect (OSTI)

    Schneider, T.C., Fluor Daniel Hanford

    1997-03-24T23:59:59.000Z

    The purpose of this test report is to document the testing performed under the guidance of HNF-SD-WM-TC-073, {ital Flammable Gas Interlock Spoolpiece Flow Response Test Plan and Procedure}. This testing was performed for Lockheed Martin Hanford Characterization Projects Operations (CPO) in support of Rotary Mode Core Sampling jointly by SGN Eurisys Services Corporation and Numatec Hanford Company. The testing was conducted in the 305 building Engineering Testing Laboratory (ETL). NHC provides the engineering and technical support for the 305 ETL. The key personnel identified for the performance of this task are as follows: Test responsible engineering manager, C. E. Hanson; Flammable Gas Interlock Design Authority, G. P. Janicek; 305 ETL responsible manager, N. J. Schliebe; Cognizant RMCS exhauster engineer, E. J. Waldo/J. D. Robinson; Cognizant 305 ETL engineer, K. S. Witwer; Test director, T. C. Schneider. Other support personnel were supplied, as necessary, from 305/306 ETL. The testing, on the flammable Gas Interlock (FGI) system spoolpiece required to support Rotary Mode Core Sampling (RMCS) of single shell flammable gas watch list tanks, took place between 2-13-97 and 2-25-97.

  16. Lattice gas automata for flow and transport in geochemical systems

    SciTech Connect (OSTI)

    Janecky, D.R.; Chen, S.; Dawson, S.; Eggert, K.C.; Travis, B.J.

    1992-05-01T23:59:59.000Z

    Lattice gas automata models are described, which couple solute transport with chemical reactions at mineral surfaces within pore networks. Diffusion in a box calculations are illustrated, which compare directly with Fickian diffusion. Chemical reactions at solid surfaces, including precipitation/dissolution, sorption, and catalytic reaction, can be examined with the model because hydrodynamic transport, solute diffusion and mineral surface processes are all treated explicitly. The simplicity and flexibility of the approach provides the ability to study the interrelationship between fluid flow and chemical reactions in porous materials, at a level of complexity that has not previously been computationally possible.

  17. Lattice gas automata for flow and transport in geochemical systems

    SciTech Connect (OSTI)

    Janecky, D.R.; Chen, S.; Dawson, S.; Eggert, K.C.; Travis, B.J.

    1992-01-01T23:59:59.000Z

    Lattice gas automata models are described, which couple solute transport with chemical reactions at mineral surfaces within pore networks. Diffusion in a box calculations are illustrated, which compare directly with Fickian diffusion. Chemical reactions at solid surfaces, including precipitation/dissolution, sorption, and catalytic reaction, can be examined with the model because hydrodynamic transport, solute diffusion and mineral surface processes are all treated explicitly. The simplicity and flexibility of the approach provides the ability to study the interrelationship between fluid flow and chemical reactions in porous materials, at a level of complexity that has not previously been computationally possible.

  18. Acoustic cross-correlation flowmeter for solid-gas flow

    DOE Patents [OSTI]

    Sheen, S.H.; Raptis, A.C.

    1984-05-14T23:59:59.000Z

    Apparatus for measuring particle velocity in a solid-gas flow within a pipe includes: first and second transmitting transducers for transmitting first and second ultrasonic signals into the pipe at first and second locations, respectively, along the pipe; an acoustic decoupler, positioned between said first and second transmitting transducers, for acoustically isolating said first and second signals from one another; first and second detecting transducers for detecting said first and second signals and for generating first and second detected signals; and means for cross-correlating said first and second output signals.

  19. Measurements of Gas Bubble Size Distributions in Flowing Liquid Mercury

    SciTech Connect (OSTI)

    Wendel, Mark W [ORNL; Riemer, Bernie [ORNL; Abdou, Ashraf A [ORNL

    2012-01-01T23:59:59.000Z

    ABSTRACT Pressure waves created in liquid mercury pulsed spallation targets have been shown to induce cavitation damage on the target container. One way to mitigate such damage would be to absorb the pressure pulse energy into a dispersed population of small bubbles, however, measuring such a population in mercury is difficult since it is opaque and the mercury is involved in a turbulent flow. Ultrasonic measurements have been attempted on these types of flows, but the flow noise can interfere with the measurement, and the results are unverifiable and often unrealistic. Recently, a flow loop was built and operated at Oak Ridge National Labarotory to assess the capability of various bubbler designs to deliver an adequate population of bubbles to mitigate cavitation damage. The invented diagnostic technique involves flowing the mercury with entrained gas bubbles in a steady state through a horizontal piping section with a glass-window observation port located on the top. The mercury flow is then suddenly stopped and the bubbles are allowed to settle on the glass due to buoyancy. Using a bright-field illumination and a high-speed camera, the arriving bubbles are detected and counted, and then the images can be processed to determine the bubble populations. After using this technique to collect data on each bubbler, bubble size distributions were built for the purpose of quantifying bubbler performance, allowing the selection of the best bubbler options. This paper presents the novel procedure, photographic technique, sample visual results and some example bubble size distributions. The best bubbler options were subsequently used in proton beam irradiation tests performed at the Los Alamos National Laboratory. The cavitation damage results from the irradiated test plates in contact with the mercury are available for correlation with the bubble populations. The most effective mitigating population can now be designed into prototypical geometries for implementation into an actual SNS target.

  20. Use of exhaust gas as sweep flow to enhance air separation membrane performance

    DOE Patents [OSTI]

    Dutart, Charles H. (Washington, IL); Choi, Cathy Y. (Morton, IL)

    2003-01-01T23:59:59.000Z

    An intake air separation system for an internal combustion engine is provided with purge gas or sweep flow on the permeate side of separation membranes in the air separation device. Exhaust gas from the engine is used as a purge gas flow, to increase oxygen flux in the separation device without increasing the nitrogen flux.

  1. Gas flow to a barometric pumping well in a multilayer unsaturated Kehua You,1

    E-Print Network [OSTI]

    Zhan, Hongbin

    Gas flow to a barometric pumping well in a multilayer unsaturated zone Kehua You,1 Hongbin Zhan,1. [1] When an open well is installed in an unsaturated zone, gas can flow between the subsurface and the well depending on the gas pressure gradient near the well. This well is called a barometric pumping

  2. Numerical Study of Hypersonic Rarefied-Gas Flows About a Toroidal Ballute

    E-Print Network [OSTI]

    Riabov, Vladimir V.

    , pressure distribution, and drag have been found. Keywords: Torus, Balloon Parachute, Transition Rarefied-GasNumerical Study of Hypersonic Rarefied-Gas Flows About a Toroidal Ballute Vladimir V. Riabov investigated numerically using the Direct Simulation Monte-Carlo technique under transition rarefied-gas flow

  3. Experimental Study of Water Droplet Flows in a Model PEM Fuel Cell Gas Microchannel

    E-Print Network [OSTI]

    Victoria, University of

    Experimental Study of Water Droplet Flows in a Model PEM Fuel Cell Gas Microchannel by Grant Minor Experimental Study of Water Droplet Flows in a Model PEM Fuel Cell Gas Microchannel by Grant Minor B. Eng. Mgmt Committee Member, Mechanical Engineering). Abstract Liquid water formation and flooding in PEM fuel cell gas

  4. Fluid and heat flow in gas-rich geothermal reservoirs

    SciTech Connect (OSTI)

    O'Sullivan, M.J.; Bodvarsson, G.S.; Pruess, K.; Blakeley, M.R.

    1983-07-01T23:59:59.000Z

    Numerical-simulation techniques are used to study the effects of noncondensible gases (CO/sub 2/) on geothermal reservoir behavior in the natural state and during exploitation. It is shown that the presence of CO/sub 2/ has large effects on the thermodynamic conditions of a reservoir in the natural state, especially on temperature distributions and phase compositions. The gas will expand two-phase zones and increase gas saturations to enable flow of CO/sub 2/ through the system. During exploitation, the early pressure drop is primarily due to degassing of the system. This process can cause a very rapid initial pressure drop, on the order of tens of bars, depending upon the initial partial pressure of CO/sub 2/. The following gas content from wells can provide information on in-place gas saturations and relative permeability curves that apply at a given geothermal resource. Site-specific studies are made for the gas-rich two-phase reservoir at the Ohaki geothermal field in New Zealand. A simple lumped-parameter model and a vertical column model are applied to the field data. The results obtained agree well with the natural thermodynamic state of the Ohaki field (pressure and temperature profiles) and a partial pressure of 15 to 25 bars is calculated in the primary reservoirs. The models also agree reasonably well with field data obtained during exploitation of the field. The treatment of thermophysical properties of H/sub 2/O-CO/sub 2/ mixtures for different phase compositions is summarized.

  5. Parametric study of flow patterns behind the standing accretion shock wave for core-collapse supernovae

    SciTech Connect (OSTI)

    Iwakami, Wakana; Nagakura, Hiroki [Yukawa Institute for Theoretical Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502 (Japan); Yamada, Shoichi, E-mail: wakana@heap.phys.waseda.ac.jp [Advanced Research Institute for Science and Engineering, Waseda University, 3-4-1, Okubo, Shinjuku, Tokyo 169-8555 (Japan)

    2014-05-10T23:59:59.000Z

    In this study, we conduct three-dimensional hydrodynamic simulations systematically to investigate the flow patterns behind the accretion shock waves that are commonly formed in the post-bounce phase of core-collapse supernovae. Adding small perturbations to spherically symmetric, steady, shocked accretion flows, we compute the subsequent evolutions to find what flow pattern emerges as a consequence of hydrodynamical instabilities such as convection and standing accretion shock instability for different neutrino luminosities and mass accretion rates. Depending on these two controlling parameters, various flow patterns are indeed realized. We classify them into three basic patterns and two intermediate ones; the former includes sloshing motion (SL), spiral motion (SP), and multiple buoyant bubble formation (BB); the latter consists of spiral motion with buoyant-bubble formation (SPB) and spiral motion with pulsationally changing rotational velocities (SPP). Although the post-shock flow is highly chaotic, there is a clear trend in the pattern realization. The sloshing and spiral motions tend to be dominant for high accretion rates and low neutrino luminosities, and multiple buoyant bubbles prevail for low accretion rates and high neutrino luminosities. It is interesting that the dominant pattern is not always identical between the semi-nonlinear and nonlinear phases near the critical luminosity; the intermediate cases are realized in the latter case. Running several simulations with different random perturbations, we confirm that the realization of flow pattern is robust in most cases.

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

    SciTech Connect (OSTI)

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

    2001-08-20T23:59:59.000Z

    The proposed research is directed at evaluating the effect of flame aerodynamics on NO{sub x} emissions from coal fired burners in a systematic manner. This fundamental research includes both experimental and modeling efforts being performed at the University of Arizona in collaboration with Purdue University. The objective of this effort is to develop rational design tools for optimizing low NO{sub x} burners to the kinetic emissions limit (below 0.2 lb./MMBTU). Experimental studies include both cold and hot flow evaluations of the following parameters: flame holder geometry, secondary air swirl, primary and secondary inlet air velocity, coal concentration in the primary air and coal particle size distribution. Hot flow experiments will also evaluate the effect of wall temperature on burner performance. Cold flow studies will be conducted with surrogate particles as well as pulverized coal. The cold flow furnace will be similar in size and geometry to the hot-flow furnace but will be designed to use a laser Doppler velocimeter/phase Doppler particle size analyzer. The results of these studies will be used to predict particle trajectories in the hot-flow furnace as well as to estimate the effect of flame holder geometry on furnace flow field. The hot-flow experiments will be conducted in a novel near-flame down-flow pulverized coal furnace. The furnace will be equipped with externally heated walls. Both reactors will be sized to minimize wall effects on particle flow fields. The cold-flow results will be compared with Fluent computation fluid dynamics model predictions and correlated with the hot-flow results with the overall goal of providing insight for novel low NO{sub x} burner geometry's.

  7. Relation between plasma plume density and gas flow velocity in atmospheric pressure plasma

    SciTech Connect (OSTI)

    Yambe, Kiyoyuki; Taka, Shogo; Ogura, Kazuo [Graduate School of Science and Technology, Niigata University, Niigata 950-2181 (Japan)] [Graduate School of Science and Technology, Niigata University, Niigata 950-2181 (Japan)

    2014-04-15T23:59:59.000Z

    We have studied atmospheric pressure plasma generated using a quartz tube, helium gas, and copper foil electrode by applying RF high voltage. The atmospheric pressure plasma in the form of a bullet is released as a plume into the atmosphere. To study the properties of the plasma plume, the plasma plume current is estimated from the difference in currents on the circuit, and the drift velocity is measured using a photodetector. The relation of the plasma plume density n{sub plu}, which is estimated from the current and the drift velocity, and the gas flow velocity v{sub gas} is examined. It is found that the dependence of the density on the gas flow velocity has relations of n{sub plu} ? log(v{sub gas}). However, the plasma plume density in the laminar flow is higher than that in the turbulent flow. Consequently, in the laminar flow, the density increases with increasing the gas flow velocity.

  8. Study of gas flow dynamics in porous and granular media with laser-polarized ą˛?Xe NMR

    E-Print Network [OSTI]

    Wang, Ruopeng, 1972-

    2005-01-01T23:59:59.000Z

    This thesis presents Nuclear Magnetic Resonance (NMR) studies of gas flow dynamics in porous and granular media by using laser-polarized ą˛?Xe . Two different physical processes, the gas transport in porous rock cores and ...

  9. Investigation of Swirl Flows Applied to the Oil and Gas Industry 

    E-Print Network [OSTI]

    Ravuri Venkata Krish, Meher Surendra

    2010-01-16T23:59:59.000Z

    Understanding how swirl flows can be applied to processes in the oil and gas industry and how problems might hinder them, are the focus of this thesis. Three application areas were identified: wet gas metering, liquid ...

  10. Coarse-scale Modeling of Flow in Gas-injection Processes for Enhanced Oil Recovery

    E-Print Network [OSTI]

    Lambers, James

    Coarse-scale Modeling of Flow in Gas-injection Processes for Enhanced Oil Recovery James V. Lambers of gas-injection processes for enhanced oil recovery may exhibit geometrically complex features

  11. Oil and Gas Flow Data from the Top Hat and from the Choke Line...

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

    Flow Data from the Top Hat and from the Choke Line - XLS Oil and Gas Flow Data from the Top Hat and from the Choke Line - XLS Updated through 12:00 AM on July 10, 2010...

  12. A Low-Cost, High-Efficiency Periodic Flow Gas Turbine for Distributed Energy Generation

    SciTech Connect (OSTI)

    Dr. Adam London

    2008-06-20T23:59:59.000Z

    The proposed effort served as a feasibility study for an innovative, low-cost periodic flow gas turbine capable of realizing efficiencies in the 39-48% range.

  13. A simple model of gas flow in a porous powder compact

    SciTech Connect (OSTI)

    Shugard, Andrew D.; Robinson, David B.

    2014-04-01T23:59:59.000Z

    This report describes a simple model for ideal gas flow from a vessel through a bed of porous material into another vessel. It assumes constant temperature and uniform porosity. Transport is treated as a combination of viscous and molecular flow, with no inertial contribution (low Reynolds number). This model can be used to fit data to obtain permeability values, determine flow rates, understand the relative contributions of viscous and molecular flow, and verify volume calibrations. It draws upon the Dusty Gas Model and other detailed studies of gas flow through porous media.

  14. air flow pattern: Topics by E-print Network

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

    for the modeling and analysis of workflows. Most workflow manage van der Aalst, Wil 110 Overheat Instability in an Ascending Moist Air Flow as a Mechanism of Hurricane Formation...

  15. air flow patterns: Topics by E-print Network

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

    for the modeling and analysis of workflows. Most workflow manage van der Aalst, Wil 110 Overheat Instability in an Ascending Moist Air Flow as a Mechanism of Hurricane Formation...

  16. Genome-wide patterns of divergence and gene flow across a butterfly radiation

    E-Print Network [OSTI]

    Mallet, James

    Genome-wide patterns of divergence and gene flow across a butterfly radiation NICOLA J. NADEAU, Panama City, Naos Island, Causeway Amador, Panama, Facultad de Ciencias Naturales y Matema butterflies are a diverse recent radiation comprising multiple levels of divergence with ongoing gene flow

  17. Measurement of Flow Phenomena in a Lower Plenum Model of a Prismatic Gas-Cooled Reactor

    SciTech Connect (OSTI)

    Hugh M. McIlroy, Jr.; Doanld M. McEligot; Robert J. Pink

    2010-02-01T23:59:59.000Z

    Mean-velocity-field and turbulence data are presented that measure turbulent flow phenomena in an approximately 1:7 scale model of a region of the lower plenum of a typical prismatic gas-cooled reactor (GCR) similar to a General Atomics Gas-Turbine-Modular Helium Reactor (GTMHR) design. The data were obtained in the Matched-Index-of-Refraction (MIR) facility at Idaho National Laboratory (INL) and are offered for assessing computational fluid dynamics (CFD) software. This experiment has been selected as the first Standard Problem endorsed by the Generation IV International Forum. Results concentrate on the region of the lower plenum near its far reflector wall (away from the outlet duct). The flow in the lower plenum consists of multiple jets injected into a confined cross flow - with obstructions. The model consists of a row of full circular posts along its centerline with half-posts on the two parallel walls to approximate geometry scaled to that expected from the staggered parallel rows of posts in the reactor design. The model is fabricated from clear, fused quartz to match the refractive-index of the working fluid so that optical techniques may be employed for the measurements. The benefit of the MIR technique is that it permits optical measurements to determine flow characteristics in complex passages in and around objects to be obtained without locating intrusive transducers that will disturb the flow field and without distortion of the optical paths. An advantage of the INL system is its large size, leading to improved spatial and temporal resolution compared to similar facilities at smaller scales. A three-dimensional (3-D) Particle Image Velocimetry (PIV) system was used to collect the data. Inlet jet Reynolds numbers (based on the jet diameter and the time-mean bulk velocity) are approximately 4,300 and 12,400. Uncertainty analyses and a discussion of the standard problem are included. The measurements reveal developing, non-uniform, turbulent flow in the inlet jets and complicated flow patterns in the model lower plenum. Data include three-dimensional vector plots, data displays along the coordinate planes (slices) and presentations that describe the component flows at specific regions in the model. Information on inlet conditions is also presented.

  18. A CFD study of gas-solid jet in a CFB riser flow

    SciTech Connect (OSTI)

    Li, Tingwen; Guenther, Chris

    2012-03-01T23:59:59.000Z

    Three-dimensional high-resolution numerical simulations of a gas–solid jet in a high-density riser flow were conducted. The impact of gas–solid injection on the riser flow hydrodynamics was investigated with respect to voidage, tracer mass fractions, and solids velocity distribution. The behaviors of a gas–solid jet in the riser crossflow were studied through the unsteady numerical simulations. Substantial separation of the jetting gas and solids in the riser crossflow was observed. Mixing of the injected gas and solids with the riser flow was investigated and backmixing of gas and solids was evaluated. In the current numerical study, both the overall hydrodynamics of riser flow and the characteristics of gas–solid jet were reasonably predicted compared with the experimental measurements made at NETL.

  19. Microscale gas flow: A comparison of Grad's 13 moment equations and other continuum approaches

    E-Print Network [OSTI]

    Victoria, University of

    Microscale gas flow: A comparison of Grad's 13 moment equations and other continuum approaches are being manufactured in quantity [2][3], e.g., pumps, turbines, valves and nozzles. These devices and chemical sensors, and fuel cells. The gas and fluid flows in devices of this size exhibit behavior that can

  20. Numerical simulations of gas-particle flows with combustion Julien NUSSBAUM

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Numerical simulations of gas-particle flows with combustion Julien NUSSBAUM French-german Research. At the initial time, the mixture of gas-powder grains is contained in the combustion chamber, limited gas species. The pressure increases in the combustion chamber, while the front flame propagates

  1. Flow Mapping in a Gas-Solid Riser via Computer Automated Radioactive Particle Tracking (CARPT)

    SciTech Connect (OSTI)

    Muthanna Al-Dahhan; Milorad P. Dudukovic; Satish Bhusarapu; Timothy J. O'hern; Steven Trujillo; Michael R. Prairie

    2005-06-04T23:59:59.000Z

    Statement of the Problem: Developing and disseminating a general and experimentally validated model for turbulent multiphase fluid dynamics suitable for engineering design purposes in industrial scale applications of riser reactors and pneumatic conveying, require collecting reliable data on solids trajectories, velocities ? averaged and instantaneous, solids holdup distribution and solids fluxes in the riser as a function of operating conditions. Such data are currently not available on the same system. Multiphase Fluid Dynamics Research Consortium (MFDRC) was established to address these issues on a chosen example of circulating fluidized bed (CFB) reactor, which is widely used in petroleum and chemical industry including coal combustion. This project addresses the problem of lacking reliable data to advance CFB technology. Project Objectives: The objective of this project is to advance the understanding of the solids flow pattern and mixing in a well-developed flow region of a gas-solid riser, operated at different gas flow rates and solids loading using the state-of-the-art non-intrusive measurements. This work creates an insight and reliable database for local solids fluid-dynamic quantities in a pilot-plant scale CFB, which can then be used to validate/develop phenomenological models for the riser. This study also attempts to provide benchmark data for validation of Computational Fluid Dynamic (CFD) codes and their current closures. Technical Approach: Non-Invasive Computer Automated Radioactive Particle Tracking (CARPT) technique provides complete Eulerian solids flow field (time average velocity map and various turbulence parameters such as the Reynolds stresses, turbulent kinetic energy, and eddy diffusivities). It also gives directly the Lagrangian information of solids flow and yields the true solids residence time distribution (RTD). Another radiation based technique, Computed Tomography (CT) yields detailed time averaged local holdup profiles at various planes. Together, these two techniques can provide the needed local solids flow dynamic information for the same setup under identical operating conditions, and the data obtained can be used as a benchmark for development, and refinement of the appropriate riser models. For the above reasons these two techniques were implemented in this study on a fully developed section of the riser. To derive the global mixing information in the riser, accurate solids RTD is needed and was obtained by monitoring the entry and exit of a single radioactive tracer. Other global parameters such as Cycle Time Distribution (CTD), overall solids holdup in the riser, solids recycle percentage at the bottom section of the riser were evaluated from different solids travel time distributions. Besides, to measure accurately and in-situ the overall solids mass flux, a novel method was applied.

  2. Bubble Size Control to Improve Oxygen-Based Bleaching: Characterization of Flow Regimes in Pulp-Water-Gas Three-Phase Flows

    SciTech Connect (OSTI)

    S.M. Ghiaasiaan and Seppo Karrila

    2006-03-20T23:59:59.000Z

    Flow characteristics of fibrous paper pulp-water-air slurries were investigated in a vertical circular column 1.8 m long, with 5.08 cm diameter. Flow structures, gas holdup (void fraction), and the geometric and population characteristics of gas bubbles were experimentally investigated, using visual observation, Gamma-ray densitometry, and flash X-ray photography. Five distinct flow regimes could be visually identified: dispersed bubbly, layered bubbly, plug, churn-turbulent, and slug. Flow regime maps were constructed, and the regime transition lines were found to be sensitive to consistency. The feasibility of using artificial neural networks (ANNs) for the identification of the flow regimes, using the statistical characteristics of pressure fluctuations measured by a single pressure sensor, was demonstrated. Local pressure fluctuations at a station were recorded with a minimally-intrusive transducer. Three-layer, feed-forward ANNs were designed that could identify the four major flow patterns (bubbly, plug, churn, and slug) well. The feasibility of a transportable artificial neural network (ANN) - based technique for the classification of flow regimes was also examined. Local pressures were recorded at three different locations using three independent but similar transducers. An ANN was designed, trained and successfully tested for the classification of the flow regimes using one of the normalized pressure signals (from Sensor 1). The ANN trained and tested for Sensor 1 predicted the flow regimes reasonably well when applied directly to the other two sensors, indicating a good deal of transportability. An ANN-based method was also developed, whereby the power spectrum density characteristics of other sensors were adjusted before they were used as input to the ANN that was based on Sensor 1 alone. The method improved the predictions. The gas-liquid interfacial surface area concentration was also measured in the study. The gas absorption technique was applied, using CO2 as the transferred species and sodium hydroxide as the alkaline agent in water. Statistical analysis was performed to identify the parametric dependencies. The experimental data were empirically correlated.

  3. Linear stability of the sub-to-super inviscid transonic stationary wave for gas flow

    E-Print Network [OSTI]

    Liu, Weishi

    -dimensional model of isentropic compressible flow through a narrow nozzle with variable cross-section area (see [2-dimensional model of isentropic compressible flows through a nozzle of varying area. This sub-to-super inviscid.P. Liu then focused on transonic waves of gas flow in a nozzle of varying area via the model (1.1) or (1

  4. Steam generators two phase flows numerical simulation with liquid and gas momentum equations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    . The secondary flow is another loop that links the steam generator and the turbines. Inside the exchangerSteam generators two phase flows numerical simulation with liquid and gas momentum equations M Abstract This work takes place in steam generators flow studies and we consider here steady state three

  5. Numerical Modeling of Reactive Multiphase Flow for FCC and Hot Gas Desulfurization Circulating Fluidized Beds

    SciTech Connect (OSTI)

    None

    2005-07-01T23:59:59.000Z

    This work was carried out to understand the behavior of the solid and gas phases in a CFB riser. Only the riser is modeled as a straight pipe. A model with linear algebraic approximation to solids viscosity of the form, {musubs} = 5.34{epsisubs}, ({espisubs} is the solids volume fraction) with an appropriate boundary condition at the wall obtained by approximate momentum balance solution at the wall to acount for the solids recirculation is tested against experimental results. The work done was to predict the flow patterns in the CFB risers from available experimental data, including data from a 7.5-cm-ID CFB riser at the Illinois Institute of Technology and data from a 20.0-cm-ID CFB riser at the Particulate Solid Research, Inc., facility. This research aims at modeling the removal of hydrogen sulfide from hot coal gas using zinc oxide as the sorbent in a circulating fluidized bed and in the process indentifying the parameters that affect the performance of the sulfidation reactor. Two different gas-solid reaction models, the unreacted shrinking core (USC) and the grain model were applied to take into account chemical reaction resistances. Also two different approaches were used to affect the hydrodynamics of the process streams. The first model takes into account the effect of micro-scale particle clustering by adjusting the gas-particle drag law and the second one assumes a turbulent core with pseudo-steady state boundary condition at the wall. A comparison is made with experimental results.

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

    SciTech Connect (OSTI)

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

    2014-04-11T23:59:59.000Z

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

  7. Zonal Flow as Pattern Formation: Merging Jets and the Ultimate Jet Length Scale

    SciTech Connect (OSTI)

    Jeffrey B. Parker and John A. Krommes

    2013-01-30T23:59:59.000Z

    Zonal flows are well known to arise spontaneously out of turbulence. It is shown that for statisti- cally averaged equations of quasigeostrophic turbulence on a beta plane, zonal flows and inhomoge- neous turbulence fit into the framework of pattern formation. There are many implications. First, the zonal flow wavelength is not unique. Indeed, in an idealized, infinite system, any wavelength within a certain continuous band corresponds to a solution. Second, of these wavelengths, only those within a smaller subband are linearly stable. Unstable wavelengths must evolve to reach a stable wavelength; this process manifests as merging jets.

  8. Ion transport membrane module and vessel system with directed internal gas flow

    DOE Patents [OSTI]

    Holmes, Michael Jerome (Thompson, ND); Ohrn, Theodore R. (Alliance, OH); Chen, Christopher Ming-Poh (Allentown, PA)

    2010-02-09T23:59:59.000Z

    An ion transport membrane system comprising (a) a pressure vessel having an interior, an inlet adapted to introduce gas into the interior of the vessel, an outlet adapted to withdraw gas from the interior of the vessel, and an axis; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region; and (c) one or more gas flow control partitions disposed in the interior of the pressure vessel and adapted to change a direction of gas flow within the vessel.

  9. The Interaction of Radio Sources and X-ray-Emitting Gas in Cooling Flows

    E-Print Network [OSTI]

    Elizabeth L. Blanton

    2004-02-13T23:59:59.000Z

    Recent observations of the interactions between radio sources and the X-ray-emitting gas in cooling flows in the cores of clusters of galaxies are reviewed. The radio sources inflate bubbles in the X-ray gas, which then rise buoyantly outward in the clusters transporting energy to the intracluster medium (ICM). The bright rims of gas around the radio bubbles are cool, rather than hot, and do not show signs of being strongly shocked. Energy deposited into the ICM over the lifetime of a cluster through several outbursts of a radio source helps to account for at least some of the gas that is missing in cooling flows at low temperatures.

  10. Influence of the gas-flow Reynolds number on a plasma column in a glass tube

    SciTech Connect (OSTI)

    Jin, Dong Jun; Uhm, Han S.; Cho, Guangsup [Department of Electronic and Biological Physics, Kwangwoon University, 20 Kwangwon-Ro, Nowon-Gu, Seoul 139-701 (Korea, Republic of)] [Department of Electronic and Biological Physics, Kwangwoon University, 20 Kwangwon-Ro, Nowon-Gu, Seoul 139-701 (Korea, Republic of)

    2013-08-15T23:59:59.000Z

    Atmospheric-plasma generation inside a glass tube is influenced by gas stream behavior as described by the Reynolds number (Rn). In experiments with He, Ne, and Ar, the plasma column length increases with an increase in the gas flow rate under laminar flow characterized by Rn < 2000. The length of the plasma column decreases as the flow rate increases in the transition region of 2000 < Rn < 4000. For a turbulent flow beyond Rn > 4000, the length of the plasma column is short in front of the electrode, eventually leading to a shutdown.

  11. A perturbation analysis of the unstable plastic flow pattern evolution in an aluminum alloy

    E-Print Network [OSTI]

    Tong, Wei

    A perturbation analysis of the unstable plastic flow pattern evolution in an aluminum alloy Seung Abstract In the tensile loading of sheet metals made from some polycrystalline aluminum alloys, a single in the uniaxial tension of polycrystalline aluminum alloys with periodic stress relaxations depends

  12. ON-LINE DETECTION OF DISTRIBUTED ATTACKS FROM SPACE-TIME NETWORK FLOW PATTERNS

    E-Print Network [OSTI]

    Baras, John S.

    ON-LINE DETECTION OF DISTRIBUTED ATTACKS FROM SPACE-TIME NETWORK FLOW PATTERNS J.S. Baras* , A in the network. We are interested in the "quickest detection" problem when the attack is distributed is to detect when a distributed denial of service is taking place in one sub-network of a transit (core

  13. 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

  14. Interference pattern of Bose-condensed gas in a 2D optical lattice

    E-Print Network [OSTI]

    Shujuan Liu; Hongwei Xiong; Zhijun Xu; Guoxiang Huang

    2003-04-25T23:59:59.000Z

    For the Bose-condensed gas confined in a magnetic trap and in a two-dimensional optical lattice, the non-uniform distribution of atoms in different lattice sites is considered based on Gross-Pitaevskii equation. A propagator method is used to investigate the time evolution of 2D interference patterns after (i)only the optical lattice is swithed off, and (ii)both the optical lattice and the magnetic trap are swithed off. An analytical description on the motion of side peaks in the interference patterns is presented by using the density distribution in a momentum space.

  15. Wastewater treatment and flow patterns in an onsite subsurface flow constructed wetland

    E-Print Network [OSTI]

    Stecher, Matthew C

    2001-01-01T23:59:59.000Z

    Subsurface flow constructed wetlands (SFCWs) are becoming increasingly common as a secondary treatment of onsite domestic wastewater. Even though SFCWs are being used widely, sufficient data has not been collected to determine how parameters...

  16. Visualization of Flow Patterns in the Bonneville 2nd Powerhouse Forebay

    SciTech Connect (OSTI)

    Serkowski, John A.; Rakowski, Cynthia L.; Ebner, Laurie L.

    2002-12-31T23:59:59.000Z

    Three-dimensional (3D) computational fluid dynamics (CFD) models are increasingly being used to study forebay and tailrace flow systems associated with hydroelectric projects. This paper describes the fundamentals of creating effective 3D data visualizations from CFD model results using a case study from the Bonneville Dam. These visualizations enhance the utility of CFD models by helping the researcher and end user better understand the model results. To develop visualizations for the Bonneville Dam forebay model, we used specialized, but commonly available software and a standard high-end microprocessor workstation. With these tools we were able to compare flow patterns among several operational scenarios by producing a variety of contour, vector, stream-trace, and vortex-core plots. The differences in flow patterns we observed could impact efforts to divert downstream-migrating fish around powerhouse turbines.

  17. 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...

  18. A phenomenological model for rarefied gas flows in thin film slider bearings 

    E-Print Network [OSTI]

    Bahukudumbi, Pradipkumar

    2002-01-01T23:59:59.000Z

    We analyze rarefied gas flows in lubricating films that form between the read/write head and rotating recording medium in computer hard drives. A modified slip-corrected Reynolds lubrication equation is derived for arbitrary ...

  19. A phenomenological model for rarefied gas flows in thin film slider bearings

    E-Print Network [OSTI]

    Bahukudumbi, Pradipkumar

    2002-01-01T23:59:59.000Z

    We analyze rarefied gas flows in lubricating films that form between the read/write head and rotating recording medium in computer hard drives. A modified slip-corrected Reynolds lubrication equation is derived for arbitrary Knudsen numbers using...

  20. A Novel Approach For the Simulation of Multiple Flow Mechanisms and Porosities in Shale Gas Reservoirs

    E-Print Network [OSTI]

    Yan, Bicheng

    2013-07-15T23:59:59.000Z

    The state of the art of modeling fluid flow in shale gas reservoirs is dominated by dual porosity models that divide the reservoirs into matrix blocks that significantly contribute to fluid storage and fracture networks which principally control...

  1. The impact of gravity segregation on multiphase non-Darcy flow in hydraulically fractured gas wells

    E-Print Network [OSTI]

    Dickins, Mark Ian

    2008-10-10T23:59:59.000Z

    Solution for Uniform Influx................................. 28 2.5 Effect of Stress on Non-Darcy Flow with Uniform Influx............................. 40 2.6 Hydraulically Fractured Reservoir with Two-Phase Flow ............................. 45 2... ............................................................................................................... 21 2.6 Gas expansion factor divided by gas viscosity Eg/µg = 1/(Bµ), which is roughly constant at or above pressures of 6,000 psi. .................................... 22 2.7 Relative permeability functions from Table 2.1 normalized...

  2. A numerical investigation of high-rate gas flow for gravel-packed completions

    E-Print Network [OSTI]

    Forrest, James Kenyon

    1983-01-01T23:59:59.000Z

    A-2 Three-Dimensional Cylindrical Grid System for Simulation of Gravel-Packed Gas Well 58 D-I Perforation Model Schematic 74 INTRODUCTION In recent years, operators have produced gas at ultra high flow rates from shallow, unconsolidated sands... the application of "Systems Analysis" to cased-hole, gravel-packed wells. The second part concerns the numerical simulation of flow in perforations and gravel-packed wells. The method presently used by some operators to analyze the productivity of wells...

  3. Diurnal patterns in crude protein and amino acid flow in the duodenum and the influence of time

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Diurnal patterns in crude protein and amino acid flow in the duodenum and the influence of time'). The mean concentration of crude protein in duodenal digesta did not differ significantly between treatments amino acids largely reflected the pattern for flow of crude protein, with the variability again being

  4. High Accuracy Numerical Methods for Thermally Perfect Gas Flows with Chemistry

    E-Print Network [OSTI]

    Soatto, Stefano

    High Accuracy Numerical Methods for Thermally Perfect Gas Flows with Chemistry Ronald P. Fedkiw with calculations of a 1-D reacting shock tube and a 2-D combustor. 2 #12; 1 Introduction Chemically reacting, high or the incineration of waste in a dump combustor. The combination of energetic chemical reactions and compressible gas

  5. THEORY OF THREE-PHASE FLOW APPLIED TO WATER-ALTERNATING-GAS ENHANCED OIL RECOVERY

    E-Print Network [OSTI]

    is the key to this improvement. 1. Introduction In secondary oil recovery, water or gas is injectedTHEORY OF THREE-PHASE FLOW APPLIED TO WATER-ALTERNATING-GAS ENHANCED OIL RECOVERY D. MARCHESIN, we show that this theory can be applied to increase the rate of oil recovery, during certain

  6. Mobile Bay gas flow rising in response to E D campaigns

    SciTech Connect (OSTI)

    Koen, A.D.

    1994-01-10T23:59:59.000Z

    Mobile Bay is fulfilling its early promise as a major US offshore gas play, nearly a quarter century after Alabama issued the first offshore leases in the area. Mobile Bay gas flow began gaining momentum in 1992, when operators in state water produced a little more than 306 MMcfd of Norphlet and Miocene gas. Alabama's offshore gas production in 1991 fell just short of 90 MMcfd, up from about 26 MMcfd in 1988. Early estimates place the state's year end 1993 offshore gas production at more than 600 MMcfd. Also at year end, major company gas plants in Mobile County, Ala., were treating more than 700 MMcfd of gas, up from 400--450 MMcfd at the beginning of the year. The paper discusses Exxon production, other major companies, Mobil's Norphlet expansions, pipeline infrastructure, federal Norphlet discoveries, Chevron's Norphlet outlook, Tenneco gathering line, gathering flexibility, Miocene gas producers, Dauphin Island Gathering System development and growth, and new Miocene producers.

  7. WETTABILITY ALTERATION OF POROUS MEDIA TO GAS-WETTING FOR IMPROVING PRODUCTIVITY AND INJECTIVITY IN GAS-LIQUID FLOWS

    SciTech Connect (OSTI)

    Abbas Firoozabadi

    2003-12-01T23:59:59.000Z

    Wettability alteration to intermediate gas-wetting in porous media by treatment with FC-759, a fluoropolymer polymer, has been studied experimentally. Berea sandstone was used as the main rock sample in our work and its wettability before and after chemical treatment was studied at various temperatures from 25 to 93 C. We also studied recovery performance for both gas/oil and oil/water systems for Berea sandstone before and after wettability alteration by chemical treatment. Our experimental study shows that chemical treatment with FC-759 can result in: (1) wettability alteration from strong liquid-wetting to stable intermediate gas-wetting at room temperature and at elevated temperatures; (2) neutral wetting for gas, oil, and water phases in two-phase flow; (3) significant increase in oil mobility for gas/oil system; and (4) improved recovery behavior for both gas/oil and oil/water systems. This work reveals a potential for field application for improved gas-well deliverability and well injectivity by altering the rock wettability around wellbore in gas condensate reservoirs from strong liquid-wetting to intermediate gas-wetting.

  8. Instability of low density supersonic waves of a viscous isentropic gas flow through a nozzle

    E-Print Network [OSTI]

    Liu, Weishi

    of isentropic compressible fluid through a narrow nozzle with variable cross-section area (see [1, 2, 3, 10, 11 flows through a nozzle with varying cross-section areas. The main result in this paper is, for small-section area a(x) is sufficiently small. T. P. Liu then focused on transonic waves of gas flow in a nozzle

  9. Effects of non-Darcy flow on pressure buildup analysis of hydraulically fractured gas reservoirs

    E-Print Network [OSTI]

    Alvarez Vera, Cesar

    2001-01-01T23:59:59.000Z

    -Darcy flow in the hydraulic fracture and its effects on pressure buildup analysis of hydraulically fractured gas reservoirs. A reservoir simulator was used to generate pressure drawdown and buildup data both with and without the effects of non-Darcy flow...

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

    E-Print Network [OSTI]

    Ewing, Richard E.

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

  11. Using multi-layer models to forecast gas flow rates in tight gas reservoirs 

    E-Print Network [OSTI]

    Jerez Vera, Sergio Armando

    2007-04-25T23:59:59.000Z

    , and (2) to use the single-layer match to demonstrate the error that can occur when forecasting long-term gas production for such complex gas reservoirs. A finite-difference reservoir simulator was used to simulate gas production from various layered tight...

  12. DEVELOPMENT OF A LOW-COST INFERENTIAL NATURAL GAS ENERGY FLOW RATE PROTOTYPE RETROFIT MODULE

    SciTech Connect (OSTI)

    E. Kelner; T.E. Owen; D.L. George; A. Minachi; M.G. Nored; C.J. Schwartz

    2004-03-01T23:59:59.000Z

    In 1998, Southwest Research Institute{reg_sign} began a multi-year project co-funded by the Gas Research Institute (GRI) and the U.S. Department of Energy. The project goal is to develop a working prototype instrument module for natural gas energy measurement. The module will be used to retrofit a natural gas custody transfer flow meter for energy measurement, at a cost an order of magnitude lower than a gas chromatograph. Development and evaluation of the prototype retrofit natural gas energy flow meter in 2000-2001 included: (1) evaluation of the inferential gas energy analysis algorithm using supplemental gas databases and anticipated worst-case gas mixtures; (2) identification and feasibility review of potential sensing technologies for nitrogen diluent content; (3) experimental performance evaluation of infrared absorption sensors for carbon dioxide diluent content; and (4) procurement of a custom ultrasonic transducer and redesign of the ultrasonic pulse reflection correlation sensor for precision speed-of-sound measurements. A prototype energy meter module containing improved carbon dioxide and speed-of-sound sensors was constructed and tested in the GRI Metering Research Facility at SwRI. Performance of this module using transmission-quality natural gas and gas containing supplemental carbon dioxide up to 9 mol% resulted in gas energy determinations well within the inferential algorithm worst-case tolerance of {+-}2.4 Btu/scf (nitrogen diluent gas measured by gas chromatograph). A two-week field test was performed at a gas-fired power plant to evaluate the inferential algorithm and the data acquisition requirements needed to adapt the prototype energy meter module to practical field site conditions.

  13. 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.

  14. Flow through shares for Natural Gas exploration (Quebec, Canada)

    Broader source: Energy.gov [DOE]

    A flow-through share is a security issued by an exploration company that waives its exploration deduction in favor of the investor. The Québec Taxation Act enables a private individual to benefit...

  15. CFD Validation of Gas Injection in Flowing Mercury over Vertical Smooth and Grooved Wall

    SciTech Connect (OSTI)

    Abdou, Ashraf A [ORNL; Wendel, Mark W [ORNL; Felde, David K [ORNL; Riemer, Bernie [ORNL

    2009-01-01T23:59:59.000Z

    The Spallation Neutron Source (SNS) is an accelerator-based neutron source at Oak Ridge National Laboratory (ORNL).The nuclear spallation reaction occurs when a proton beam hits liquid mercury. This interaction causes thermal expansion of the liquid mercury which produces high pressure waves. When these pressure waves hit the target vessel wall, cavitation can occur and erode the wall. Research and development efforts at SNS include creation of a vertical protective gas layer between the flowing liquid mercury and target vessel wall to mitigate the cavitation damage erosion and extend the life time of the target. Since mercury is opaque, computational fluid dynamics (CFD) can be used as a diagnostic tool to see inside the liquid mercury and guide the experimental efforts. In this study, CFD simulations of three dimensional, unsteady, turbulent, two-phase flow of helium gas injection in flowing liquid mercury over smooth, vertically grooved and horizontally grooved walls are carried out with the commercially available CFD code Fluent-12 from ANSYS. The Volume of Fluid (VOF) model is used to track the helium-mercury interface. V-shaped vertical and horizontal grooves with 0.5 mm pitch and about 0.7 mm depth were machined in the transparent wall of acrylic test sections. Flow visualization data of helium gas coverage through transparent test sections is obtained with a high-speed camera at the ORNL target test facility (TTF). The helium gas mass flow rate is 8 mg/min and introduced through a 0.5 mm diameter port. The local mercury velocity is 0.9 m/s. In this paper, the helium gas flow rate and the local mercury velocity are kept constant for the three cases. Time integration of predicted helium gas volume fraction over time is done to evaluate the gas coverage and calculate the average thickness of the helium gas layer. The predicted time-integrated gas coverage over vertically grooved and horizontally grooved test sections is better than over a smooth wall. The simulations show that the helium gas is trapped inside the grooves. The predicted time-averaged gas coverage is in good qualitative agreement with the measured gas coverage.

  16. Planarization of amorphous carbon films on patterned substrates using gas cluster ion beams

    SciTech Connect (OSTI)

    Toyoda, Noriaki; Yamada, Isao [Incubation Center, University of Hyogo, 2167 Shosha, Himeji, Hyogo 671-2280 (Japan); Nagato, Keisuke; Nakao, Masayuki; Hamaguchi, Tetsuya [Department of Engineering Synthesis, School of Engineering, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Tani, Hiroshi [Department of Mechanical Engineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Sakane, Yasuo [Western Digital Media Operations, 1710 Automation Parkway, San Jose, CA 95131 (United States)

    2009-04-01T23:59:59.000Z

    Surface planarization and modification of a patterned surface were demonstrated using gas cluster ion beam (GCIB). Grooves with 100-400 nm intervals were formed on amorphous carbon films using focused ion beams to study the special frequency dependence of the planarization. Also, line and space patterns were fabricated on Si substrates, and amorphous carbons were deposited as a model structure of discrete track media. Subsequently, surface planarization using Ar-GCIB was carried out. After GCIB irradiations, all of the grooves were completely removed, and a flat surface was realized. And it showed that GCIB irradiation planarized grooves without huge thickness loss. From the power spectrum density of an atomic force microscope, GCIB preferentially removed grooves with small intervals. It was found from energy dispersive x-ray spectroscopy that surface planarization without severe damage in the amorphous carbon and magnetic layers was carried out with GCIB.

  17. Contemporary Mathematics A Numerical Simulation of Multicomponent Gas Flow in

    E-Print Network [OSTI]

    Ewing, Richard E.

    and gravitational e#11;ects. Traditionally, the standard Darcy equation provides this relation. In this paper, however, we replace this classical law with the Forchheimer equation to model non-Darcy ow [F, RM, HG]. The Forchheimer equation is believed to be more accurate than the classical Darcy's equation for gas ow with high

  18. Manufacturability of lab on chip devices : reagent-filled reservoirs bonding process and its effect on reagents flow pattern

    E-Print Network [OSTI]

    Saber, Aabed (Aabed Saud)

    2013-01-01T23:59:59.000Z

    In its lab-on-a-chip product, Daktari Diagnostics utilizes "reagent-filled reservoirs" as a means of storing and delivering the liquid reagent. During the clinical trials of the product, undesired reagent flow patterns ...

  19. UK Oil and Gas Collaborative Doctoral Training Centre (2014 start) Project Title: Coupled flow of water and gas during hydraulic fracture in shale (EARTH-15-CM1)

    E-Print Network [OSTI]

    Henderson, Gideon

    UK Oil and Gas Collaborative Doctoral Training Centre (2014 start) Project Title: Coupled flow of water and gas during hydraulic fracture in shale (EARTH-15-CM1) Host institution: University of Oxford Cartwright Project description: Recovery of natural gas from mudstone (shale) formations has triggered

  20. Centers of Barred Galaxies: Secondary Bars and Gas Flows

    E-Print Network [OSTI]

    Witold Maciejewski

    1999-11-15T23:59:59.000Z

    Active Galactic Nuclei (AGN) require mass accretion onto the central engine. On large galactic scales, torques from a stellar bar can efficiently remove angular momentum from gas, and cause it to move inwards along two hydrodynamical shocks on the leading edges of the bar. Inflowing gas settles on near-circular orbits around the Inner Lindblad Resonance (ILR), and forms a nuclear ring, about 1 kpc in size. A secondary bar inside the main one, with its own pair of shocks, has been proposed to drive further inflow, and thus feed the AGN in a manner similar to the inflow on large scales. Here, we report results of high resolution hydrodynamical simulations, where we examine the nature of the nuclear ring, and check how efficient double bars can be in fueling AGNs.

  1. Closed cycle MHD generator with nonuniform gas-plasma flow driving recombinated plasma clots

    SciTech Connect (OSTI)

    Slavin, V.S. [Krasnoyarsk State Technical Univ. (Russian Federation); Danilov, V.V.; Sokolov, V.S. [Krasnoyarsk State Univ. (Russian Federation)

    1996-12-31T23:59:59.000Z

    A new concept of a closed cycle MHD generator without alkali seed has been suggested. The essence of it is the phenomenon of frozen conductivity for recombined plasma which appears for noble gas at T{sub e} > 4,000 K. At the inlet of the MHD channel in supersonic flow of noble gas (He or Ar) the plasma clots with electron density about 10{sup 15} cm{sup {minus}3} are formed by pulsed intense electron beam with energy about 300 keV. Gas flow drives these clots in a cross magnetic field along the MHD channel which has electrodes connected with the load by Faraday scheme. The gas flow pushes plasma layers and produces electric power at the expense of enthalpy extraction. The numerical simulation has shown that a supersonic gas flow, containing about 4 plasma layers in the MHD channel simultaneously, is braked without shock waves creation. This type of the MHD generator can provide more than 30% enthalpy extraction ratio and about 80% isentropic efficiency. The advantages of the new concept are the following: (a) possibility of working at higher pressure and lower temperature, (b) operation with alkali seed.

  2. A system for the real time, direct measurement of natural gas flow

    SciTech Connect (OSTI)

    Sowell, T. [PMI, Badger Meter, Inc., Tulsa, OK (United States)

    1995-12-31T23:59:59.000Z

    PMI/Badger Meter, Inc. with partial sponsorship from the Gas Research Institute, has designed and developed direct measurement total energy flow metering instrumentation. As industry demands for improved accuracy and speed of measurement have increased so has the complexity of the overall hardware and software systems. Considering traditional system approaches, few companies have the in house capability of maintaining a complete system. This paper addresses efforts to implement a direct, total gas energy flow metering system which is simple to use and cost effective.

  3. Determination of the effect of gas viscosity upon gas flow in permeable media containing water and gas

    E-Print Network [OSTI]

    Stegemeier, Richard Joseph

    1952-01-01T23:59:59.000Z

    ?ateredeaturated Natural Gas Visoositiss at Varieua PPISSQreao ~ ~ ~ o e ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 32 VI Ns~tura+ed gitrogen Viscosities 0't Varieue h%00uraee ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ eel 33 VII Das Wbili... pressure to 1500 ysi per yccryoses of flew work~ tho viscosities af aitrogen aud tho natural gas wbou saturated with water vapor were also detercdcmd Sco basis yerpese of this pre)set was te dsteruine ths offset of the vtsoosQy of a gas nyon the web...

  4. Couette flow regimes with heat transfer in rarefied gas

    SciTech Connect (OSTI)

    Abramov, A. A., E-mail: alabr54@mail.ru; Butkovskii, A. V., E-mail: albutkov@mail.ru [Zhukovski Central Aerohydrodynamics Institute (Russian Federation)

    2013-06-15T23:59:59.000Z

    Based on numerical solution of the Boltzmann equation by direct statistic simulation, the Couette flow with heat transfer is studied in a broad range of ratios of plate temperatures and Mach numbers of a moving plate. Flow regime classification by the form of the dependences of the energy flux and friction stress on the Knudsen number Kn is proposed. These dependences can be simultaneously monotonic and nonmonotonic and have maxima. Situations are possible in which the dependence of the energy flux transferred to a plate on Kn has a minimum, while the dependence of the friction stress is monotonic or even has a maximum. Also, regimes exist in which the dependence of the energy flux on Kn has a maximum, while the dependence of the friction stress is monotonic, and vice versa.

  5. Determination of the effect of gas viscosity upon gas flow in permeable media containing water and gas 

    E-Print Network [OSTI]

    Stegemeier, Richard Joseph

    1952-01-01T23:59:59.000Z

    Of Alanlts ~ ~ ~ o ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ \\ ~ ~ ~ ~ ~ ~ ~ ~ o ~ ~ ~ ~ ~ ~ ~ ~ ~ 46 Gsndlnaionso ~ ~ , o ~ ~ ~ ~ ~ o ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ o ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 49 50 kdtSN... uovoaout of gas menses whish eaecncpass a naaber af porose and in whish tho gas phase is oouttnaoaa. Lhycid sataraticms af tho oore wore obtained bf fractional OMdPOtiT1t7 RMHIMMhth 4 1 pFOMIM INllillt tl Mll I MS straeted to obtain the satoratinu...

  6. Method For Enhanced Gas Monitoring In High Density Flow Streams

    DOE Patents [OSTI]

    Von Drasek, William A. (Oak Forest, IL); Mulderink, Kenneth A. (Countryside, IL); Marin, Ovidiu (Lisle, IL)

    2005-09-13T23:59:59.000Z

    A method for conducting laser absorption measurements in high temperature process streams having high levels of particulate matter is disclosed. An impinger is positioned substantially parallel to a laser beam propagation path and at upstream position relative to the laser beam. Beam shielding pipes shield the beam from the surrounding environment. Measurement is conducted only in the gap between the two shielding pipes where the beam propagates through the process gas. The impinger facilitates reduced particle presence in the measurement beam, resulting in improved SNR (signal-to-noise) and improved sensitivity and dynamic range of the measurement.

  7. Creating Small Gas Bubbles in Flowing Mercury Using Turbulence at an Orifice

    SciTech Connect (OSTI)

    Wendel, Mark W [ORNL; Abdou, Ashraf A [ORNL; Paquit, Vincent C [ORNL; Felde, David K [ORNL; Riemer, Bernie [ORNL

    2010-01-01T23:59:59.000Z

    Pressure waves created in liquid mercury pulsed spallation targets have been shown to create cavitation damage to the target container. One way to mitigate such damage would be to absorb the pressure pulse energy into a dispersed population of small bubbles, however, creating such a population in mercury is difficult due to the high surface tension and particularly the non-wetting behavior of mercury on gas-injection hardware. If the larger injected gas bubbles can be broken down into small bubbles after they are introduced to the flow, then the material interface problem is avoided. Research at the Oak Ridge National Labarotory is underway to develop a technique that has shown potential to provide an adequate population of small-enough bubbles to a flowing spallation target. This technique involves gas injection at an orifice of a geometry that is optimized to the turbulence intensity and pressure distribution of the flow, while avoiding coalescence of gas at injection sites. The most successful geometry thus far can be described as a square-toothed orifice having a 2.5 bar pressure drop in the nominal flow of 12 L/s for one of the target inlet legs. High-speed video and high-resolution photography have been used to quantify the bubble population on the surface of the mercury downstream of the gas injection sight. Also, computational fluid dynamics has been used to optimize the dimensions of the toothed orifice based on a RANS computed mean flow including turbulent energies such that the turbulent dissipation and pressure field are best suited for turbulent break-up of the gas bubbles.

  8. Influence of hydrogen patterning gas on electric and magnetic properties of perpendicular magnetic tunnel junctions

    SciTech Connect (OSTI)

    Jeong, J. H., E-mail: juno@fris.tohoku.ac.jp [Graduate School of Engineering, Tohoku University, Sendai (Japan); Semiconductor R and D Center, Samsung Electronics Co., Ltd., Hwasung (Korea, Republic of); Endoh, T. [Graduate School of Engineering, Tohoku University, Sendai (Japan); Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai (Japan); Kim, Y.; Kim, W. K.; Park, S. O. [Semiconductor R and D Center, Samsung Electronics Co., Ltd., Hwasung (Korea, Republic of)

    2014-05-07T23:59:59.000Z

    To identify the degradation mechanism in magnetic tunnel junctions (MTJs) using hydrogen, the properties of the MTJs were measured by applying an additional hydrogen etch process and a hydrogen plasma process to the patterned MTJs. In these studies, an additional 50?s hydrogen etch process caused the magnetoresistance (MR) to decrease from 103% to 14.7% and the resistance (R) to increase from 6.5?k? to 39?k?. Moreover, an additional 500?s hydrogen plasma process decreased the MR from 103% to 74% and increased R from 6.5?k? to 13.9?k?. These results show that MTJs can be damaged by the hydrogen plasma process as well as by the hydrogen etch process, as the atomic bonds in MgO may break and react with the exposed hydrogen gas. Compounds such as MgO hydrate very easily. We also calculated the damaged layer width (DLW) of the patterned MTJs after the hydrogen etching and plasma processes, to evaluate the downscaling limitations of spin-transfer-torque magnetic random-access memory (STT-MRAM) devices. With these calculations, the maximum DLWs at each side of the MTJ, generated by the etching and plasma processes, were 23.8?nm and 12.8?nm, respectively. This result validates that the hydrogen-based MTJ patterning processes cannot be used exclusively in STT-MRAMs beyond 20?nm.

  9. Stress-induced patterns in ion-irradiated Silicon: a model based on anisotropic plastic flow

    E-Print Network [OSTI]

    Scott A. Norris

    2012-07-24T23:59:59.000Z

    We present a model for the effect of stress on thin amorphous films that develop atop ion-irradiated silicon, based on the mechanism of ion-induced anisotropic plastic flow. Using only parameters directly measured or known to high accuracy, the model exhibits remarkably good agreement with the wavelengths of experimentally-observed patterns, and agrees qualitatively with limited data on ripple propagation speed. The predictions of the model are discussed in the context of other mechanisms recently theorized to explain the wavelengths, including extensive comparison with an alternate model of stress.

  10. Using multi-layer models to forecast gas flow rates in tight gas reservoirs

    E-Print Network [OSTI]

    Jerez Vera, Sergio Armando

    2007-04-25T23:59:59.000Z

    pressure at the inner boundary. He combined a back-pressure gas rate equation (Eq 2.9) with the materials balance equation Eq 2.10 onto a rate-time equation for gas wells as described in Eq 2.11, and then he generated the new set of type curves as shown.......................................................................................... 10 2.1 Introduction ...................................................................................................10 2.2 Decline Curve Analysis...

  11. Closures for Course-Grid Simulation of Fluidized Gas-Particle Flows

    SciTech Connect (OSTI)

    Sankaran Sundaresan

    2010-02-14T23:59:59.000Z

    Gas-particle flows in fluidized beds and riser reactors are inherently unstable, and they manifest fluctuations over a wide range of length and time scales. Two-fluid models for such flows reveal unstable modes whose length scale is as small as ten particle diameters. Yet, because of limited computational resources, gas-particle flows in large fluidized beds are invariably simulated by solving discretized versions of the two-fluid model equations over a coarse spatial grid. Such coarse-grid simulations do not resolve the small-scale spatial structures which are known to affect the macroscale flow structures both qualitatively and quantitatively. Thus there is a need to develop filtered two-fluid models which are suitable for coarse-grid simulations and capturing the effect of the small-scale structures through closures in terms of the filtered variables. The overall objective of the project is to develop validated closures for filtered two-fluid models for gas-particle flows, with the transport gasifier as a primary, motivating example. In this project, highly resolved three-dimensional simulations of a kinetic theory based two-fluid model for gas-particle flows have been performed and the statistical information on structures in the 100-1000 particle diameters length scale has been extracted. Based on these results, closures for filtered two-fluid models have been constructed. The filtered model equations and closures have been validated against experimental data and the results obtained in highly resolved simulations of gas-particle flows. The proposed project enables more accurate simulations of not only the transport gasifier, but also many other non-reacting and reacting gas-particle flows in a variety of chemical reactors. The results of this study are in the form of closures which can readily be incorporated into existing multi-phase flow codes such as MFIX (www.mfix.org). Therefore, the benefits of this study can be realized quickly. The training provided by this project has prepared a PhD student to enter research and development careers in DOE laboratories or chemicals/energy-related industries.

  12. Capacitance-based prover for gas flow meters

    E-Print Network [OSTI]

    Pipkins, Sean Patrick

    1995-01-01T23:59:59.000Z

    ;?= enthalpy of the air at the inlet. H Uo =U +RT Uo =Cv(T To)+RT, (36) 24 Equation (35) can be written as c (T-T)=[c (T?? T)+RT. , ?] Il ? ' n j (37) Solving Equation (37) for T gives the equation used to calculate the temperature profiles of the air.... . . . . Relation of Capacitance Change to Molar Flow Rate. DiIferential Method Integral Method THEORETICAL CALCULATIONS. Calculated C. Experimental C. Thermal Expansion Effects . . Capacitance Change Due to Length Change Capacitance Change Due to Radius...

  13. EIA - Natural Gas Pipeline Network - Transportation Process & Flow

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Year-0E (2001)gasoline353/06)Pipeline UtilizationProcess and Flow

  14. 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)

  15. Flow analysis and nozzle-shape optimization for the cold-gas dynamic-spray process

    E-Print Network [OSTI]

    Grujicic, Mica

    Flow analysis and nozzle-shape optimization for the cold-gas dynamic-spray process M Grujicic1*, W, maximizes the acceleration of the particles. Furthermore, it is found that if the cold-spray nozzle, a significant increase in the average velocity of the particles at the nozzle exit can be obtained

  16. Study of Gas Flow Dynamics in Porous and Granular Media with Laser-Polarized 129

    E-Print Network [OSTI]

    Walsworth, Ronald L.

    Abstract This thesis presents Nuclear Magnetic Resonance (NMR) studies of gas flow dynamics in porous in porous rock cores and the mass exchanges between different phases in fluidized granular systems, were-emulsion exchange and emulsion-adsorption exchange in a fluidized bed are two processes crucial to the efficiency

  17. Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs

    SciTech Connect (OSTI)

    Maria Cecilia Bravo

    2006-06-30T23:59:59.000Z

    This document reports progress of this research effort in identifying relationships and defining dependencies between macroscopic reservoir parameters strongly affected by microscopic flow dynamics and production well performance in tight gas sand reservoirs. These dependencies are investigated by identifying the main transport mechanisms at the pore scale that should affect fluids flow at the reservoir scale. A critical review of commercial reservoir simulators, used to predict tight sand gas reservoir, revealed that many are poor when used to model fluid flow through tight reservoirs. Conventional simulators ignore altogether or model incorrectly certain phenomena such as, Knudsen diffusion, electro-kinetic effects, ordinary diffusion mechanisms and water vaporization. We studied the effect of Knudsen's number in Klinkenberg's equation and evaluated the effect of different flow regimes on Klinkenberg's parameter b. We developed a model capable of explaining the pressure dependence of this parameter that has been experimentally observed, but not explained in the conventional formalisms. We demonstrated the relevance of this, so far ignored effect, in tight sands reservoir modeling. A 2-D numerical simulator based on equations that capture the above mentioned phenomena was developed. Dynamic implications of new equations are comprehensively discussed in our work and their relative contribution to the flow rate is evaluated. We performed several simulation sensitivity studies that evidenced that, in general terms, our formalism should be implemented in order to get more reliable tight sands gas reservoirs' predictions.

  18. The mechanical analogy for the flow of gas

    E-Print Network [OSTI]

    Flanagan, Lindley Eric

    1953-01-01T23:59:59.000Z

    the pointer to aery Thus~ ~p ia related. to p by the expression & & =pAp5, where 'the dista1icea are shown be]pw. . Pressure Panel Assembly, P= jap~, nd 2 = f&, Ib, For this flow channel, Q =, OIZ65 oZ, 5 = 4 7Z =~. G8 ID. , so that p p=. ODS5 2 The ea...'~ Y !. '" ~i, ~j l P $ '*'A P: ' 7'l $" " 6' ~ ~:r*. ;~~;, '? r, ". ~ pr~, ~?r~, yi, c;mg g~l'1 II!LT" j, ' I . ". v N1". a$ A; *W, M" f 't "w gltg x""Ri% 7 vH p '4, "2 WYt'. ?C Q ' $ ?:f' fl $ "p". & 'I pl' p-lp QQSf'; jQWg~ ig& !ply &P[ 'ggg...

  19. Pore-scale mechanisms of gas flow in tight sand reservoirs

    SciTech Connect (OSTI)

    Silin, D.; Kneafsey, T.J.; Ajo-Franklin, J.B.; Nico, P.

    2010-11-30T23:59:59.000Z

    Tight gas sands are unconventional hydrocarbon energy resource storing large volume of natural gas. Microscopy and 3D imaging of reservoir samples at different scales and resolutions provide insights into the coaredo not significantly smaller in size than conventional sandstones, the extremely dense grain packing makes the pore space tortuous, and the porosity is small. In some cases the inter-granular void space is presented by micron-scale slits, whose geometry requires imaging at submicron resolutions. Maximal Inscribed Spheres computations simulate different scenarios of capillary-equilibrium two-phase fluid displacement. For tight sands, the simulations predict an unusually low wetting fluid saturation threshold, at which the non-wetting phase becomes disconnected. Flow simulations in combination with Maximal Inscribed Spheres computations evaluate relative permeability curves. The computations show that at the threshold saturation, when the nonwetting fluid becomes disconnected, the flow of both fluids is practically blocked. The nonwetting phase is immobile due to the disconnectedness, while the permeability to the wetting phase remains essentially equal to zero due to the pore space geometry. This observation explains the Permeability Jail, which was defined earlier by others. The gas is trapped by capillarity, and the brine is immobile due to the dynamic effects. At the same time, in drainage, simulations predict that the mobility of at least one of the fluids is greater than zero at all saturations. A pore-scale model of gas condensate dropout predicts the rate to be proportional to the scalar product of the fluid velocity and pressure gradient. The narrowest constriction in the flow path is subject to the highest rate of condensation. The pore-scale model naturally upscales to the Panfilov's Darcy-scale model, which implies that the condensate dropout rate is proportional to the pressure gradient squared. Pressure gradient is the greatest near the matrix-fracture interface. The distinctive two-phase flow properties of tight sand imply that a small amount of gas condensate can seriously affect the recovery rate by blocking gas flow. Dry gas injection, pressure maintenance, or heating can help to preserve the mobility of gas phase. A small amount of water can increase the mobility of gas condensate.

  20. Lattice Boltzmann method and gas-kinetic BGK scheme in the low-Mach number viscous flow simulations

    E-Print Network [OSTI]

    Xu, Kun

    and collisions process. On the other hand, the gas-kinetic BGK scheme is a finite volume scheme, where the timeLattice Boltzmann method and gas-kinetic BGK scheme in the low-Mach number viscous flow simulations method (LBM) and the gas-kinetic BGK scheme are based on the numerical discretization of the Boltzmann

  1. Application of convolution theory for solving non-linear flow problems: gas flow systems

    E-Print Network [OSTI]

    Mireles, Thomas Joseph

    1995-01-01T23:59:59.000Z

    . . . . . . . . . . . . 15 3. 2. 1 Generalized Analytical Solution for Real Gas Systems . . . . . . . . 15 3. 2. 2 Dry Gas Material Balance Relations: P(tn) - g(u) Identity. . . . . . 16 3. 3 Functional and Numerical Data Models for the Non-Linear CHAPTER IV Component... of the functions. " By applying this theorem and taking the Laplace transform of the right hand side of Eq. 3. 1 (expressed by Eq. 3. 3), we obtain Eq. 3. 4. Q(ft * fj)(t)) = ft(u) g(u) . where the non-linear transform function is given as g(u) = X(g(t)) . (3...

  2. Turbine exhaust diffuser with a gas jet producing a coanda effect flow control

    DOE Patents [OSTI]

    Orosa, John; Montgomery, Matthew

    2014-02-11T23:59:59.000Z

    An exhaust diffuser system and method for a turbine engine includes an inner boundary and an outer boundary with a flow path defined therebetween. The inner boundary is defined at least in part by a hub structure that has an upstream end and a downstream end. The outer boundary may include a region in which the outer boundary extends radially inward toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. The hub structure includes at least one jet exit located on the hub structure adjacent to the upstream end of the tail cone. The jet exit discharges a flow of gas substantially tangential to an outer surface of the tail cone to produce a Coanda effect and direct a portion of the exhaust flow in the diffuser toward the inner boundary.

  3. 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...

  4. Corrosion-induced gas generation in a nuclear waste repository: Reactive geochemistry and multiphase flow effect

    SciTech Connect (OSTI)

    Xu, T.; Senger, R.; Finsterle, S.

    2008-10-15T23:59:59.000Z

    Corrosion of steel canisters, stored in a repository for spent fuel and high-level nuclear wastes, leads to the generation and accumulation of hydrogen gas in the backfilled emplacement tunnels, which may significantly affect long-term repository safety. Previous studies used H{sub 2} generation rates based on the volume of the waste or canister material and the stoichiometry of the corrosion reaction. However, iron corrosion and H{sub 2} generation rates vary with time, depending on factors such as amount of iron, water availability, water contact area, and aqueous and solid chemistry. To account for these factors and feedback mechanisms, we developed a chemistry model related to iron corrosion, coupled with two-phase (liquid and gas) flow phenomena that are driven by gas-pressure buildup associated with H{sub 2} generation and water consumption. Results indicate that by dynamically calculating H{sub 2} generation rates based on a simple model of corrosion chemistry, and by coupling this corrosion reaction with two-phase flow processes, the degree and extent of gas pressure buildup could be much smaller compared to a model that neglects the coupling between flow and reactive transport mechanisms. By considering the feedback of corrosion chemistry, the gas pressure increases initially at the canister, but later decreases and eventually returns to a stabilized pressure that is slightly higher than the background pressure. The current study focuses on corrosion under anaerobic conditions for which the coupled hydrogeochemical model was used to examine the role of selected physical parameters on the H{sub 2} gas generation and corresponding pressure buildup in a nuclear waste repository. The developed model can be applied to evaluate the effect of water and mineral chemistry of the buffer and host rock on the corrosion reaction for future site-specific studies.

  5. Using DSMC to compute the force on a particle in a rarefied gas flow.

    SciTech Connect (OSTI)

    Gallis, Michail A.; Rader, Daniel John; Torczynski, John Robert

    2002-06-01T23:59:59.000Z

    An approach is presented to compute the force on a spherical particle in a rarefied flow of a monatomic gas. This approach relies on the development of a Green's function that describes the force on a spherical particle in a delta-function molecular velocity distribution function. The gas-surface interaction model in this development allows incomplete accommodation of energy and tangential momentum. The force from an arbitrary molecular velocity distribution is calculated by computing the moment of the force Green's function in the same way that other macroscopic variables are determined. Since the molecular velocity distribution function is directly determined in the DSMC method, the force Green's function approach can be implemented straightforwardly in DSMC codes. A similar approach yields the heat transfer to a spherical particle in a rarefied gas flow. The force Green's function is demonstrated by application to two problems. First, the drag force on a spherical particle at arbitrary temperature and moving at arbitrary velocity through an equilibrium motionless gas is found analytically and numerically. Second, the thermophoretic force on a motionless particle in a motionless gas with a heat flux is found analytically and numerically. Good agreement is observed in both situations.

  6. New U. S. gas lines will restructure North American grid flows

    SciTech Connect (OSTI)

    Spiegel, E.; Johnson, E. Jr. (Booz-Allen and Hamilton Inc., Dallas, TX (US)); Viscio, A.

    1990-12-10T23:59:59.000Z

    This paper reports that completion of several major U.S. natural-gas pipeline projects will significantly change relationships among suppliers, buyers, and transporters; alter pipeline flows and tariffs; and affect producer economics. The competitive and regulatory environment of the natural-gas industry continues to change under great uncertainty. Within this rapidly changing environment, many long-discussed but often-delayed pipeline projects are nearing or have entered the construction phase. These projects represent more than 5 bcf/day (bcfd) of capacity targeting three major markets that now consume an average of 23 bcfd.

  7. Two dimensional flow of a compressible gas in a thin passage

    E-Print Network [OSTI]

    Desai, Anantkumar Ratanji

    1971-01-01T23:59:59.000Z

    ) (Member) (Member) (Me ber) (Member) August 1971 ABSTRACT Two Dimensional Flow of a Compressible Gas in a Thin Passage (August 1971) Anantkumar Ratangi Desai, B. E. , University of Bombay; Directed by: Dr. Meherwan P. Boyce The present report... assumptions that restrict its applicability. The equations describing the flow are: 2 n ? - ~+ 3 u 3 2 Bx By p u ? + v ? (1) (Navier-Stokes Eqn. ) r 3 3 3 Bx By J 3, /Bu u ? + p ? + Bx ( Bx (2) (Continuity-Eqn. ) BT BD pCpu ? u ~ Bx Bx (3) (Energy...

  8. Using a multiphase flow code to model the coupled effects of repository consolidation and multiphase brine and gas flow at the Waste Isolation Pilot Plant

    SciTech Connect (OSTI)

    Freeze, G.A. [INTERA Inc., Albuquerque, NM (United States); Larson, K.W.; Davies, P.B.; Webb, S.W. [Sandia National Labs., Albuquerque, NM (United States)

    1995-10-01T23:59:59.000Z

    Long-term repository assessment must consider the processes of (1) gas generation, (2) room closure and expansions due to salt creep, and (3) multiphase (brine and gas) fluid flow, as well as the complex coupling between these three processes. The mechanical creep closure code SANCHO was used to simulate the closure of a single, perfectly sealed disposal room filled with water and backfill. SANCHO uses constitutive models to describe salt creep, waste consolidation, and backfill consolidation, Five different gas-generation rate histories were simulated, differentiated by a rate multiplier, f, which ranged from 0.0 (no gas generation) to 1.0 (expected gas generation under brine-dominated conditions). The results of the SANCHO f-series simulations provide a relationship between gas generation, room closure, and room pressure for a perfectly sealed room. Several methods for coupling this relationship with multiphase fluid flow into and out of a room were examined. Two of the methods are described.

  9. Numerical Simulation of Rarefied-Gas Flows about a Rotating Cylinder

    E-Print Network [OSTI]

    Riabov, Vladimir V.

    -Gas Flows, Aerodynamic Coefficients. PACS: 47.11.Mn, 47.27 ek, 47.32 Ef, 47.45 n, 47.85 Gj. NOMENCLATURE Cx. The lift and drag coefficients Cy,FM and Cx,FM , respectively, can be calculated using the formulae [6]: Cy,FM = Cy (0) + Cy (W), Cy (W) = ( /2) t W (1) Cx,FM = Cx (0) + Cx (W), Cx (W) = 0 (2) where the parameter

  10. Modeling and experiments on differential pumping in linear plasma generators operating at high gas flows

    SciTech Connect (OSTI)

    Eck, H. J. N. van; Koppers, W. R.; Rooij, G. J. van; Goedheer, W. J.; Cardozo, N. J. Lopes; Kleyn, A. W. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Engeln, R.; Schram, D. C. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

    2009-03-15T23:59:59.000Z

    The direct simulation Monte Carlo (DSMC) method was used to investigate the efficiency of differential pumping in linear plasma generators operating at high gas flows. Skimmers are used to separate the neutrals from the plasma beam, which is guided from the source to the target by a strong axial magnetic field. In this way, the neutrals are prevented to reach the target region. The neutral flux to the target must be lower than the plasma flux to enable ITER relevant plasma-surface interaction (PSI) studies. It is therefore essential to control the neutral gas dynamics. The DSMC method was used to model the expansion of a hot gas in a low pressure vessel where a small discrepancy in shock position was found between the simulations and a well-established empirical formula. Two stage differential pumping was modeled and applied in the linear plasma devices Pilot-PSI and PLEXIS. In Pilot-PSI a factor of 4.5 pressure reduction for H{sub 2} has been demonstrated. Both simulations and experiments showed that the optimum skimmer position depends on the position of the shock and therefore shifts for different gas parameters. The shape of the skimmer has to be designed such that it has a minimum impact on the shock structure. A too large angle between the skimmer and the forward direction of the gas flow leads to an influence on the expansion structure. A pressure increase in front of the skimmer is formed and the flow of the plasma beam becomes obstructed. It has been shown that a skimmer with an angle around 53 deg. gives the best performance. The use of skimmers is implemented in the design of the large linear plasma generator Magnum-PSI. Here, a three stage differentially pumped vacuum system is used to reach low enough neutral pressures near the target, opening a door to PSI research in the ITER relevant regime.

  11. Modifications to a two-control-volume, frequency dependent, transfer-function analysis of hole-pattern gas annular seals

    E-Print Network [OSTI]

    Shin, Yoon Shik

    2007-04-25T23:59:59.000Z

    ............................................................................................ 12 5. EFFECT OF REAL GAS PROPERTIES .................................................................. 24 6. EFFECT OF STATOR-HOLE-DEPTH VARIATION ............................................. 32 7. EFFECT OF DEEP ANNULAR GROOVE................................................ 4 3 Flow in and out through control volume surface ...................................................... 5 4 Direct stiffness K(f) vs. non-dimensional frequency f for smooth seal.................... 13 5 Cross-coupled stiffness k(f) vs. non...

  12. Enhanced membrane gas separations

    SciTech Connect (OSTI)

    Prasad, R.

    1993-07-13T23:59:59.000Z

    An improved membrane gas separation process is described comprising: (a) passing a feed gas stream to the non-permeate side of a membrane system adapted for the passage of purge gas on the permeate side thereof, and for the passage of the feed gas stream in a counter current flow pattern relative to the flow of purge gas on the permeate side thereof, said membrane system being capable of selectively permeating a fast permeating component from said feed gas, at a feed gas pressure at or above atmospheric pressure; (b) passing purge gas to the permeate side of the membrane system in counter current flow to the flow of said feed gas stream in order to facilitate carrying away of said fast permeating component from the surface of the membrane and maintaining the driving force for removal of the fast permeating component through the membrane from the feed gas stream, said permeate side of the membrane being maintained at a subatmospheric pressure within the range of from about 0.1 to about 5 psia by vacuum pump means; (c) recovering a product gas stream from the non-permeate side of the membrane; and (d) discharging purge gas and the fast permeating component that has permeated the membrane from the permeate side of the membrane, whereby the vacuum conditions maintained on the permeate side of the membrane by said vacuum pump means enhance the efficiency of the gas separation operation, thereby reducing the overall energy requirements thereof.

  13. Hydrodynamic and statistical parameters of slug flow Lev Shemer *

    E-Print Network [OSTI]

    Shemer, Lev

    distribution within the pipeline is of utmost importance and requires proper knowledge of the relevant and dispersed gas bubbles in pipelines of various inclina- tions. In vertical slug flow most of the gas-phase slug flow pattern, the bulk of the gas is trapped inside large bubbles that are separated by liquid

  14. Heat Flow and Gas Hydrates on the Continental Margin of India: Building on Results from NGHP Expedition 01

    SciTech Connect (OSTI)

    Anne Trehu; Peter Kannberg

    2011-06-30T23:59:59.000Z

    The Indian National Gas Hydrate Program (NGHP) Expedition 01 presented the unique opportunity to constrain regional heat flow derived from seismic observations by using drilling data in three regions on the continental margin of India. The seismic bottom simulating reflection (BSR) is a well-documented feature in hydrate bearing sediments, and can serve as a proxy for apparent heat flow if data are available to estimate acoustic velocity and density in water and sediments, thermal conductivity, and seafloor temperature. Direct observations of temperature at depth and physical properties of the sediment obtained from drilling can be used to calibrate the seismic observations, decreasing the uncertainty of the seismically-derived estimates. Anomalies in apparent heat flow can result from a variety of sources, including sedimentation, erosion, topographic refraction and fluid flow. We constructed apparent heat flow maps for portions of the Krishna-Godavari (K-G) basin, the Mahanadi basin, and the Andaman basin and modeled anomalies using 1-D conductive thermal models. Apparent heat flow values in the Krishna-Godavari (K-G) basin and Mahanadi basin are generally 0.035 to 0.055 watts per square meter (W/m{sup 2}). The borehole data show an increase in apparent heat flow as water depth increases from 900 to 1500 m. In the SW part of the seismic grid, 1D modeling of the effect of sedimentation on heat flow shows that {approx}50% of the observed increase in apparent heat flow with increasing water depth can be attributed to trapping of sediments behind a 'toe-thrust' ridge that is forming along the seaward edge of a thick, rapidly accumulating deltaic sediment pile. The remainder of the anomaly can be explained either by a decrease in thermal conductivity of the sediments filling the slope basin or by lateral advection of heat through fluid flow along stratigraphic horizons within the basin and through flexural faults in the crest of the anticline. Such flow probably plays a role in bringing methane into the ridge formed by the toe-thrust. Because of the small anomaly due to this process and the uncertainty in thermal conductivity, we did not model this process explicitly. In the NE part of the K-G basin seismic grid, a number of local heat flow lows and highs are observed, which can be attributed to topographic refraction and to local fluid flow along faults, respectively. No regional anomaly can be resolved. Because of lack of continuity between the K-G basin sites within the seismic grid and those {approx}70 km to the NE in water depths of 1200 to 1500 m, we do not speculate on the reason for higher heat flow at these depths. The Mahanadi basin results, while limited in geographic extent, are similar to those for the K-G basin. The Andaman basin exhibits much lower apparent heat flow values, ranging from 0.015 to 0.025 W/m{sup 2}. Heat flow here also appears to increase with increasing water depth. The very low heat flow here is among the lowest heat flow observed anywhere and gives rise to a very thick hydrate stability zone in the sediments. Through 1D models of sedimentation (with extremely high sedimentation rates as a proxy for tectonic thickening), we concluded that the very low heat flow can probably be attributed to the combined effects of high sedimentation rate, low thermal conductivity, tectonic thickening of sediments and the cooling effect of a subducting plate in a subduction zone forearc. Like for the K-G basin, much of the local variability can be attributed to topography. The regional increase in heat flow with water depth remains unexplained because the seismic grid available to us did not extend far enough to define the local tectonic setting of the slope basin controlling this observational pattern. The results are compared to results from other margins, both active and passive. While an increase in apparent heat flow with increasing water depth is widely observed, it is likely a result of different processes in different places. The very low heat flow due to sedimentation and tectonics in the Andaman basi

  15. Heat Flow and Gas Hydrates on the Continental Margin of India: Building on Results from NGHP Expedition 01

    SciTech Connect (OSTI)

    Trehu, Anne; Kannberg, Peter

    2011-06-30T23:59:59.000Z

    The Indian National Gas Hydrate Program (NGHP) Expedition 01 presented the unique opportunity to constrain regional heat flow derived from seismic observations by using drilling data in three regions on the continental margin of India. The seismic bottom simulating reflection (BSR) is a well-documented feature in hydrate bearing sediments, and can serve as a proxy for apparent heat flow if data are available to estimate acoustic velocity and density in water and sediments, thermal conductivity, and seafloor temperature. Direct observations of temperature at depth and physical properties of the sediment obtained from drilling can be used to calibrate the seismic observations, decreasing the uncertainty of the seismically-derived estimates. Anomalies in apparent heat flow can result from a variety of sources, including sedimentation, erosion, topographic refraction and fluid flow. We constructed apparent heat flow maps for portions of the Krishna-Godavari (K-G) basin, the Mahanadi basin, and the Andaman basin and modeled anomalies using 1-D conductive thermal models. Apparent heat flow values in the Krishna-Godavari (K-G) basin and Mahanadi basin are generally 0.035 to 0.055 watts per square meter (W/m2). The borehole data show an increase in apparent heat flow as water depth increases from 900 to 1500 m. In the SW part of the seismic grid, 1D modeling of the effect of sedimentation on heat flow shows that ~50% of the observed increase in apparent heat flow with increasing water depth can be attributed to trapping of sediments behind a "toe-thrust" ridge that is forming along the seaward edge of a thick, rapidly accumulating deltaic sediment pile. The remainder of the anomaly can be explained either by a decrease in thermal conductivity of the sediments filling the slope basin or by lateral advection of heat through fluid flow along stratigraphic horizons within the basin and through flexural faults in the crest of the anticline. Such flow probably plays a role in bringing methane into the ridge formed by the toe-thrust. Because of the small anomaly due to this process and the uncertainty in thermal conductivity, we did not model this process explicitly. In the NE part of the K-G basin seismic grid, a number of local heat flow lows and highs are observed, which can be attributed to topographic refraction and to local fluid flow along faults, respectively. No regional anomaly can be resolved. Because of lack of continuity between the K-G basin sites within the seismic grid and those ~70 km to the NE in water depths of 1200 to 1500 m, we do not speculate on the reason for higher heat flow at these depths. The Mahanadi basin results, while limited in geographic extent, are similar to those for the KG basin. The Andaman basin exhibits much lower apparent heat flow values, ranging from 0.015 to 0.025 W/m2. Heat flow here also appears to increase with increasing water depth. The very low heat flow here is among the lowest heat flow observed anywhere and gives rise to a very thick hydrate stability zone in the sediments. Through 1D models of sedimentation (with extremely high sedimentation rates as a proxy for tectonic thickening), we concluded that the very low heat flow can probably be attributed to the combined effects of high sedimentation rate, low thermal conductivity, tectonic thickening of sediments and the cooling effect of a subducting plate in a subduction zone forearc. Like for the K-G basin, much of the local variability can be attributed to topography. The regional increase in heat flow with water depth remains unexplained because the seismic grid available to us did not extend far enough to define the local tectonic setting of the slope basin controlling this observational pattern. The results are compared to results from other margins, both active and passive. While an increase in apparent heat flow with increasing water depth is widely observed, it is likely a result of different processes in different places. The very low heat flow due to sedimentation and tectonics in the Andaman basin is at the low end of glob

  16. Spatial patterns of flow and their modification within and around a giant kelp forest Brian Gaylord1

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Spatial patterns of flow and their modification within and around a giant kelp forest Brian Gaylord and over the full extent of a giant kelp (Macrocystis pyrifera) forest located at Mohawk Reef, Santa reported for larger (kilometer-scale) kelp beds, suggesting that alongshore currents may play a greater

  17. A Simplified Solution For Gas Flow During a Blow-out in an H2 or Air Storage Cavern

    E-Print Network [OSTI]

    Boyer, Edmond

    A Simplified Solution For Gas Flow During a Blow-out in an H2 or Air Storage Cavern Pierre BĂ©rest, Milano, Italy Abstract A small number of blow-outs from gas storage caverns (for example, in Moss Bluff and hydrogen storage in salt caverns. Compressed Air Energy Storage (CAES) is experiencing a rise in interest

  18. CFD Simulation of 3D Flow field in a Gas Centrifuge

    SciTech Connect (OSTI)

    Dongjun Jiang; Shi Zeng [Tsinghua University, Beijing, 100084 (China)

    2006-07-01T23:59:59.000Z

    A CFD method was used to study the whole flow field in a gas centrifuge. In this paper, the VSM (Vector Splitting Method) of the FVM (Finite Volume Method) was used to solve the 3D Navier-Stokes equations. An implicit second-order upwind scheme was adopted. The numerical simulation was successfully performed on a parallel cluster computer and a convergence result was obtained. The simulation shows that: in the withdrawal chamber, a strong detached shock wave is formed in front of the scoop; as the radial position increases, the shock becomes stronger and the distance to scoop front surface is smaller. An oblique shock forms in the clearance between the scoop and the centrifuge wall; behind the shock-wave, the radially-inward motion of gas is induced because of the imbalance of the pressure gradient and the centrifugal force. In the separation chamber, a countercurrent is introduced. This indicates that CFD method can be used to study the complex three-dimensional flow field of gas centrifuges. (authors)

  19. Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs

    SciTech Connect (OSTI)

    Maria Cecilia Bravo; Mariano Gurfinkel

    2005-06-30T23:59:59.000Z

    This document reports progress of this research effort in identifying possible relationships and defining dependencies between macroscopic reservoir parameters strongly affected by microscopic flow dynamics and production well performance in tight gas sand reservoirs. Based on a critical review of the available literature, a better understanding of the main weaknesses of the current state of the art of modeling and simulation for tight sand reservoirs has been reached. Progress has been made in the development and implementation of a simple reservoir simulator that is still able to overcome some of the deficiencies detected. The simulator will be used to quantify the impact of microscopic phenomena in the macroscopic behavior of tight sand gas reservoirs. Phenomena such as, Knudsen diffusion, electro-kinetic effects, ordinary diffusion mechanisms and water vaporization are being considered as part of this study. To date, the adequate modeling of gas slippage in porous media has been determined to be of great relevance in order to explain unexpected fluid flow behavior in tight sand reservoirs.

  20. Determination of the permeability of carbon aerogels by gas flow measurements

    SciTech Connect (OSTI)

    Kong, F.M.; Hulsey, S.S.; Alviso, C.T.; Pekala, R.W.

    1992-04-01T23:59:59.000Z

    Carbon aerogels are synthesized via the polycondensation of resorcinol and formaldehyde, followed by supercritical drying and pyrolysis at 1050{degree}C in nitrogen. Because of their interconnected porosity, ultrafine cell structure and high surface area, carbon aerogels have many potential applications, such as in supercapacitors, battery electrodes, catalyst supports, and gas filters. The performance of carbon aerogels in the latter two applications depends on the permeability or gas flow conductance in these materials. By measuring the pressure differential across a thin specimen and the nitrogen gas flow rate in the viscous regime, we calculated the permeability of carbon aerogels from equations based upon Darcy`s law. Our measurements show that carbon aerogels have apparent permeabilities on the order of 10{sup {minus}12}to 10{sup {minus}10} cm{sup 2} for densities ranging from 0.44 to 0.05 g/cm{sup 3}. Like their mechanical properties, the permeability of carbon aerogels follows a power law relationship with density and average pore size. Such findings help us to estimate the average pore sizes of carbon aerogels once their densities are known. This paper reveals the relationships among permeability, pore size and density in carbon aerogels.

  1. Determination of the permeability of carbon aerogels by gas flow measurements

    SciTech Connect (OSTI)

    Kong, F.M.; Hulsey, S.S.; Alviso, C.T.; Pekala, R.W.

    1992-04-01T23:59:59.000Z

    Carbon aerogels are synthesized via the polycondensation of resorcinol and formaldehyde, followed by supercritical drying and pyrolysis at 1050{degree}C in nitrogen. Because of their interconnected porosity, ultrafine cell structure and high surface area, carbon aerogels have many potential applications, such as in supercapacitors, battery electrodes, catalyst supports, and gas filters. The performance of carbon aerogels in the latter two applications depends on the permeability or gas flow conductance in these materials. By measuring the pressure differential across a thin specimen and the nitrogen gas flow rate in the viscous regime, we calculated the permeability of carbon aerogels from equations based upon Darcy's law. Our measurements show that carbon aerogels have apparent permeabilities on the order of 10{sup {minus}12}to 10{sup {minus}10} cm{sup 2} for densities ranging from 0.44 to 0.05 g/cm{sup 3}. Like their mechanical properties, the permeability of carbon aerogels follows a power law relationship with density and average pore size. Such findings help us to estimate the average pore sizes of carbon aerogels once their densities are known. This paper reveals the relationships among permeability, pore size and density in carbon aerogels.

  2. Preliminary Study of Turbulent Flow in the Lower Plenum of a Gas-Cooled Reactor

    SciTech Connect (OSTI)

    T. Gallaway; D.P. Guillen; H.M. McIlroy, Jr.; S.P. Antal

    2007-09-01T23:59:59.000Z

    A preliminary study of the turbulent flow in a scaled model of a portion of the lower plenum of a gas-cooled advanced reactor concept has been conducted. The reactor is configured such that hot gases at various temperatures exit the coolant channels in the reactor core, where they empty into a lower plenum and mix together with a crossflow past vertical cylindrical support columns, then exit through an outlet duct. An accurate assessment of the flow behavior will be necessary prior to final design to ensure that material structural limits are not exceeded. In this work, an idealized model was created to mimic a region of the lower plenum for a simplified set of conditions that enabled the flow to be treated as an isothermal, incompressible fluid with constant properties. This is a first step towards assessing complex thermal fluid phenomena in advanced reactor designs. Once such flows can be computed with confidence, heated flows will be examined. Experimental data was obtained using three-dimensional Particle Image Velocimetry (PIV) to obtain non-intrusive flow measurements for an unheated geometry. Computational fluid dynamic (CFD) predictions of the flow were made using a commercial CFD code and compared to the experimental data. The work presented here is intended to be scoping in nature, since the purpose of this work is to identify improvements that can be made to subsequent computations and experiments. Rigorous validation of computational predictions will eventually be necessary for design and analysis of new reactor concepts, as well as for safety analysis and licensing calculations.

  3. Pair interaction lattice gas simulations: Flow past obstacles in two and three dimensions

    SciTech Connect (OSTI)

    Vogeler, A.; Wolf-Gladrow, D.A. (Alfred-Wegener-Institute for Polar and Marine Research, Bremerhaven (Germany))

    1993-04-01T23:59:59.000Z

    Apart from the FCHC (face-centered hypercube), Nasilowski's pair interaction lattice gas (PI) is the only known lattice gas automaton for three-dimensional hydrodynamic simulations. Unfortunately, the viscosity of PI is not isotropic. In order to determine the degree anisotropy, the authors derive fluid dynamic equations for the regime of compressible viscid flow. From relaxation measurements of waves propagating in various directions they compute the physically relevant dissipation coefficients and compare their results with theoretical predictions. Although PI shows a high degree of anisotropy, they define the mean value of the dissipation tensor as effective shear viscosity. Using this value of v[sub eff][sup 2D] = 0.35, two-dimensional simulations of flow past a cylinder yield drag coefficients in quantitative agreement with wind tunnel measurements over a range of Reynolds numbers of 5-50. Three-dimensional simulations of flow past a sphere yield qualitative agreement with various references. A fit of the results to a semi-empirical curve provides an effective value of v[sub eff][sup 2D] = 0.21 for a range of Reynolds numbers from 0.19 to 40. In order to check for finite-size effects, the authors measured the mean free path [lambda] and computed the Knudsen numbers. They obtained [lambda] [approx]1 lattice unit, corresponding to Kn = 0.01 (2D) and Kn = 0.1 (3D). They found no significant finite-size effects. 44 refs., 10 figs.

  4. An efficient particle Fokker–Planck algorithm for rarefied gas flows

    SciTech Connect (OSTI)

    Gorji, M. Hossein; Jenny, Patrick

    2014-04-01T23:59:59.000Z

    This paper is devoted to the algorithmic improvement and careful analysis of the Fokker–Planck kinetic model derived by Jenny et al. [1] and Gorji et al. [2]. The motivation behind the Fokker–Planck based particle methods is to gain efficiency in low Knudsen rarefied gas flow simulations, where conventional direct simulation Monte Carlo (DSMC) becomes expensive. This can be achieved due to the fact that the resulting model equations are continuous stochastic differential equations in velocity space. Accordingly, the computational particles evolve along independent stochastic paths and thus no collision needs to be calculated. Therefore the computational cost of the solution algorithm becomes independent of the Knudsen number. In the present study, different computational improvements were persuaded in order to augment the method, including an accurate time integration scheme, local time stepping and noise reduction. For assessment of the performance, gas flow around a cylinder and lid driven cavity flow were studied. Convergence rates, accuracy and computational costs were compared with respect to DSMC for a range of Knudsen numbers (from hydrodynamic regime up to above one). In all the considered cases, the model together with the proposed scheme give rise to very efficient yet accurate solution algorithms.

  5. Gas-powder flow in blast furnace with different shapes of cohesive zone

    SciTech Connect (OSTI)

    Dong, X.F.; Pinson, D.; Zhang, S.J.; Yu, A.B.; Zulli, P. [University of New South Wales, Sydney, NSW (Australia)

    2006-11-15T23:59:59.000Z

    With high PCI rate operations, a large quantity of unburned coal/char fines will flow together with the gas into the blast furnace. Under some operating conditions, the holdup of fines results in deterioration of furnace permeability and lower production efficiency. Therefore, it is important to understand the behaviour of powder (unburnt coal/char) inside the blast furnace when operating with different cohesive zone (CZ) shapes. This work is mainly concerned with the effect of cohesive zone shape on the powder flow and accumulation in a blast furnace. A model is presented which is capable of simulating a clear and stable accumulation region in the lower central region of the furnace. The results indicate that powder is likely to accumulate at the lower part of W-shaped CZs and the upper part of V- and inverse V-shaped CZs. For the same CZ shape, a thick cohesive layer can result in a large pressure drop while the resistance of narrow cohesive layers to gas-powder flow is found to be relatively small. Implications of the findings to blast furnace operation are also discussed.

  6. Controlling fuel and diluent gas flow for a diesel engine operating in the fuel rich low-temperature-combustion mode

    E-Print Network [OSTI]

    Lopez, David M

    2007-01-01T23:59:59.000Z

    The flow of a diluent gas supplied to a motoring engine was controlled at a diluent to air mass flow ratios of 10%, 30%, 50%, and 70%. This arrangement was a significant set up for running the engine in the Low-Temperature ...

  7. Rotordynamic evaluation of frequency dependent impedances of hole-pattern gas damper seals

    E-Print Network [OSTI]

    Holt, Christopher George

    2000-01-01T23:59:59.000Z

    Two hole-pattern seals are compared with one smooth bore seal. The two hole-pattern seals have cell depths of 2.03 mm and 3.18 mm with a cell diameter of 1.59 mm. The hole area density factor for both hole-pattern seals is 43%. The L/D ratio...

  8. DEVELOPMENT OF A LOW COST INFERENTIAL NATURAL GAS ENERGY FLOW RATE PROTOTYPE RETROFIT MODULE

    SciTech Connect (OSTI)

    E. Kelner; D. George; T. Morrow; T. Owen; M. Nored; R. Burkey; A. Minachi

    2005-05-01T23:59:59.000Z

    In 1998, Southwest Research Institute began a multi-year project to develop a working prototype instrument module for natural gas energy measurement. The module will be used to retrofit a natural gas custody transfer flow meter for energy measurement, at a cost an order of magnitude lower than a gas chromatograph. Development and evaluation of the prototype energy meter in 2002-2003 included: (1) refinement of the algorithm used to infer properties of the natural gas stream, such as heating value; (2) evaluation of potential sensing technologies for nitrogen content, improvements in carbon dioxide measurements, and improvements in ultrasonic measurement technology and signal processing for improved speed of sound measurements; (3) design, fabrication and testing of a new prototype energy meter module incorporating these algorithm and sensor refinements; and (4) laboratory and field performance tests of the original and modified energy meter modules. Field tests of the original energy meter module have provided results in close agreement with an onsite gas chromatograph. The original algorithm has also been tested at a field site as a stand-alone application using measurements from in situ instruments, and has demonstrated its usefulness as a diagnostic tool. The algorithm has been revised to use measurement technologies existing in the module to measure the gas stream at multiple states and infer nitrogen content. The instrumentation module has also been modified to incorporate recent improvements in CO{sub 2} and sound speed sensing technology. Laboratory testing of the upgraded module has identified additional testing needed to attain the target accuracy in sound speed measurements and heating value.

  9. Characterization of the reactive flow field dynamics in a gas turbine injector using high frequency PIV

    E-Print Network [OSTI]

    Barbosa, Séverine; Ducruix, Sébastien

    2008-01-01T23:59:59.000Z

    The present work details the analysis of the aerodynamics of an experimental swirl stabilized burner representative of gas turbine combustors. This analysis is carried out using High Frequency PIV (HFPIV) measurements in a reactive situation. While this information is usually available at a rather low rate, temporally resolved PIV measurements are necessary to better understand highly turbulent swirled flows, which are unsteady by nature. Thanks to recent technical improvements, a PIV system working at 12 kHz has been developed to study this experimental combustor flow field. Statistical quantities of the burner are first obtained and analyzed, and the measurement quality is checked, then a temporal analysis of the velocity field is carried out, indicating that large coherent structures periodically appear in the combustion chamber. The frequency of these structures is very close to the quarter wave mode of the chamber, giving a possible explanation for combustion instability coupling.

  10. A gas kinetic scheme for the Baer-Nunziato two-phase flow model

    SciTech Connect (OSTI)

    Pan, Liang, E-mail: panliangjlu@sina.com [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China) [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); The Graduate School of China Academy of Engineering Physics, Beijing 100088 (China); Zhao, Guiping, E-mail: zhaogp@nsfc.gov.cn [National Natural Science Foundation of China, Beijing 100085 (China)] [National Natural Science Foundation of China, Beijing 100085 (China); Tian, Baolin, E-mail: tian_baolin@iapcm.ac.cn [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China) [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Wang, Shuanghu, E-mail: wang_shuanghu@iapcm.ac.cn [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China) [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China)

    2012-09-15T23:59:59.000Z

    Numerical methods for the Baer-Nunziato (BN) two-phase flow model have attracted much attention in recent years. In this paper, we present a new gas kinetic scheme for the BN two-phase flow model containing non-conservative terms in the framework of finite volume method. In the view of microscopic aspect, a generalized Bhatnagar-Gross-Krook (BGK) model which matches with the BN model is constructed. Based on the integral solution of the generalized BGK model, we construct the distribution functions at the cell interface. Then numerical fluxes can be obtained by taking moments of the distribution functions, and non-conservative terms are explicitly introduced into the construction of numerical fluxes. In this method, not only the complex iterative process of exact solutions is avoided, but also the non-conservative terms included in the equation can be handled well.

  11. Fundamentals of Natural Gas and Species Flows from Hydrate Dissociation - Applications to Safety and Sea Floor Instability

    SciTech Connect (OSTI)

    Goodarz Ahmadi

    2006-09-30T23:59:59.000Z

    Semi-analytical computational models for natural gas flow in hydrate reservoirs were developed and the effects of variations in porosity and permeability on pressure and temperature profiles and the movement of a dissociation front were studied. Experimental data for variations of gas pressure and temperature during propane hydrate formation and dissociation for crushed ice and mixture of crushed ice and glass beads under laboratory environment were obtained. A thermodynamically consistent model for multiphase liquid-gas flows trough porous media was developed. Numerical models for hydrate dissociation process in one dimensional and axisymmetric reservoir were performed. The computational model solved the general governing equations without the need for linearization. A detail module for multidimensional analysis of hydrate dissociation which make use of the FLUENT code was developed. The new model accounts for gas and liquid water flow and uses the Kim-Boshnoi model for hydrate dissociation.

  12. Efficient boron nitride nanotube formation via combined laser-gas flow levitation

    DOE Patents [OSTI]

    Whitney, R. Roy; Jordan, Kevin; Smith, Michael

    2014-03-18T23:59:59.000Z

    A process for producing boron nitride nanotubes and/or boron-carbon-nitrogen nanotubes of the general formula B.sub.xC.sub.yN.sub.z. The process utilizes a combination of laser light and nitrogen gas flow to support a boron ball target during heating of the boron ball target and production of a boron vapor plume which reacts with nitrogen or nitrogen and carbon to produce boron nitride nanotubes and/or boron-carbon-nitrogen nanotubes of the general formula B.sub.xC.sub.yN.sub.z.

  13. Galactic scale gas flows in colliding galaxies: 3-Dimensional, N-body/hydrodynamics experiments

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.Newof EnergyFunding OpportunityF G FGalactic Scale Gas Flows

  14. 3D Modeling of One and Two Component Gas Flow in Fibrous Microstructures in Fuel Cells by Using the Lattice-Boltzmann Method

    E-Print Network [OSTI]

    Schmidt, Volker

    In fuel cells, a homogeneous distribution of gas flow is desirable for optimal performance. The gas3D Modeling of One and Two Component Gas Flow in Fibrous Microstructures in Fuel Cells by Using: Fuel Cells, 52425 Jülich, Germany b Institute of Stochastics, Ulm University, 89069 Ulm, Germany

  15. Heat flow patterns of the North American continent: A discussion of the DNAG Geothermal Map of North America

    SciTech Connect (OSTI)

    Blackwell, David D.; Steele, John L.; Carter, Larry C.

    1990-01-01T23:59:59.000Z

    The large and small-scale geothermal features of the North American continent and surrounding ocean areas illustrated on the new 1:5,000,000 DNAG Geothermal Map of North America are summarized. Sources for the data included on the map are given. The types of data included are heat flow sites coded by value, contours of heat flow with a color fill, areas of major groundwater effects on regional heat flow, the top-of-geopressure in the Gulf Coast region, temperature on the Dakota aquifer in the midcontinent, location of major hot springs and geothermal systems, and major center of Quaternary and Holocene volcanism. The large scale heat flow pattern that is well known for the conterminous United States and Canada of normal heat flow east of the Cordillera and generally high heat flow west of the front of the Cordillera dominates the continental portion of the map. However, details of the heat flow variations are also seen and are discussed briefly in this and the accompanying papers.

  16. Two phase partially miscible flow and transport modeling in porous media: application to gas migration in a nuclear waste repository

    E-Print Network [OSTI]

    Bourgeat, Alain; Smaď, Farid

    2008-01-01T23:59:59.000Z

    We derive a compositional compressible two-phase, liquid and gas, flow model for numerical simulations of hydrogen migration in deep geological repository for radioactive waste. This model includes capillary effects and the gas high diffusivity. Moreover, it is written in variables (total hydrogen mass density and liquid pressure) chosen in order to be consistent with gas appearance or disappearance. We discuss the well possedness of this model and give some computational evidences of its adequacy to simulate gas generation in a water saturated repository.

  17. Two phase partially miscible flow and transport modeling in porous media: application to gas migration in a nuclear waste repository

    E-Print Network [OSTI]

    Alain Bourgeat; Mladen Jurak; Farid Smaď

    2008-02-29T23:59:59.000Z

    We derive a compositional compressible two-phase, liquid and gas, flow model for numerical simulations of hydrogen migration in deep geological repository for radioactive waste. This model includes capillary effects and the gas high diffusivity. Moreover, it is written in variables (total hydrogen mass density and liquid pressure) chosen in order to be consistent with gas appearance or disappearance. We discuss the well possedness of this model and give some computational evidences of its adequacy to simulate gas generation in a water saturated repository.

  18. Numerical modeling of carrier gas flow in atomic layer deposition vacuum reactor: A comparative study of lattice Boltzmann models

    SciTech Connect (OSTI)

    Pan, Dongqing; Chien Jen, Tien [Department of Mechanical Engineering, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201 (United States); Li, Tao [School of Mechanical Engineering, Dalian University of Technology, Dalian 116024 (China); Yuan, Chris, E-mail: cyuan@uwm.edu [Department of Mechanical Engineering, University of Wisconsin-Milwaukee, 3200 North Cramer Street, Milwaukee, Wisconsin 53211 (United States)

    2014-01-15T23:59:59.000Z

    This paper characterizes the carrier gas flow in the atomic layer deposition (ALD) vacuum reactor by introducing Lattice Boltzmann Method (LBM) to the ALD simulation through a comparative study of two LBM models. Numerical models of gas flow are constructed and implemented in two-dimensional geometry based on lattice Bhatnagar–Gross–Krook (LBGK)-D2Q9 model and two-relaxation-time (TRT) model. Both incompressible and compressible scenarios are simulated and the two models are compared in the aspects of flow features, stability, and efficiency. Our simulation outcome reveals that, for our specific ALD vacuum reactor, TRT model generates better steady laminar flow features all over the domain with better stability and reliability than LBGK-D2Q9 model especially when considering the compressible effects of the gas flow. The LBM-TRT is verified indirectly by comparing the numerical result with conventional continuum-based computational fluid dynamics solvers, and it shows very good agreement with these conventional methods. The velocity field of carrier gas flow through ALD vacuum reactor was characterized by LBM-TRT model finally. The flow in ALD is in a laminar steady state with velocity concentrated at the corners and around the wafer. The effects of flow fields on precursor distributions, surface absorptions, and surface reactions are discussed in detail. Steady and evenly distributed velocity field contribute to higher precursor concentration near the wafer and relatively lower particle velocities help to achieve better surface adsorption and deposition. The ALD reactor geometry needs to be considered carefully if a steady and laminar flow field around the wafer and better surface deposition are desired.

  19. DESIGN AND DEVELOPMENT OF GAS-LIQUID CYLINDRICAL CYCLONE COMPACT SEPARATORS FOR THREE-PHASE FLOW

    SciTech Connect (OSTI)

    Dr. Ram S. Mohan; Dr. Ovadia Shoham

    2003-06-25T23:59:59.000Z

    The U.S. Department of Energy (DOE) has awarded a five-year (1997-2002) grant (Mohan and Shoham, DE-FG26-97BC15024, 1997) to The University of Tulsa, to develop compact multiphase separation components for 3-phase flow. The research activities of this project have been conducted through cost sharing by the member companies of the Tulsa University Separation Technology Projects (TUSTP) research consortium and the Oklahoma Center for the Advancement of Science and Technology (OCAST). As part of this project, several individual compact separation components have been developed for onshore and offshore applications. These include gas-liquid cylindrical cyclones (GLCC{copyright}), liquid-liquid cylindrical cyclones (LLCC{copyright}), and the gas-liquid-liquid cylindrical cyclones (GLLCC{copyright}). A detailed study has also been completed for the liquid-liquid hydrocyclones (LLHC). Appropriate control strategies have been developed for proper operation of the GLCC{copyright} and LLCC{copyright}. Testing of GLCC{copyright} at high pressure and real crude conditions for field applications is also completed. Limited studies have been conducted on flow conditioning devices to be used upstream of the compact separators for performance improvement. This report presents a brief overview of the activities and tasks accomplished during the 5-year project period, October 1, 1997-March 31, 2003 (including the no-cost extended period of 6 months). An executive summary is presented initially followed by the tasks of the 5-year budget periods. Then, detailed description of the experimental and modeling investigations are presented. Subsequently, the technical and scientific results of the activities of this project period are presented with some discussions. The findings of this investigation are summarized in the ''Conclusions'' section, followed by relevant references. The publications resulting from this study in the form of MS Theses, Ph.D. Dissertation, Journal Papers and Conference Presentations are provided at the end of this report.

  20. COARSE-GRID SIMULATION OF REACTING AND NON-REACTING GAS-PARTICLE FLOWS

    SciTech Connect (OSTI)

    Sankaran Sundaresan

    2004-03-01T23:59:59.000Z

    The principal goal of this project, funded under the ''DOE Vision 21 Virtual Demonstration Initiative'' is virtual demonstration of circulating fluidized bed performance. We had proposed a ''virtual demonstration tool'', which is based on the open-domain CFD code MFIX. The principal challenge funded through this grant is to devise and implement in this CFD code sound physical models for the rheological characteristics of the gas-particle mixtures. Within the past year, which was the third year of the project, we have made the following specific advances. (a) We have completed a study of the impact of sub-grid models of different levels of detail on the results obtained in coarse-grid simulations of gas-particle flow. (b) We have also completed a study of a model problem to understand the effect of wall friction, which was proved in our earlier work to be very important for stable operation of standpipes in a circulating fluidized bed circuit. These are described in a greater detail in this report.

  1. A Finite-Difference Numerical Method for Onsager's Pancake Approximation for Fluid Flow in a Gas Centrifuge

    SciTech Connect (OSTI)

    de Stadler, M; Chand, K

    2007-11-12T23:59:59.000Z

    Gas centrifuges exhibit very complex flows. Within the centrifuge there is a rarefied region, a transition region, and a region with an extreme density gradient. The flow moves at hypersonic speeds and shock waves are present. However, the flow is subsonic in the axisymmetric plane. The analysis may be simplified by treating the flow as a perturbation of wheel flow. Wheel flow implies that the fluid is moving as a solid body. With the very large pressure gradient, the majority of the fluid is located very close to the rotor wall and moves at an azimuthal velocity proportional to its distance from the rotor wall; there is no slipping in the azimuthal plane. The fluid can be modeled as incompressible and subsonic in the axisymmetric plane. By treating the centrifuge as long, end effects can be appropriately modeled without performing a detailed boundary layer analysis. Onsager's pancake approximation is used to construct a simulation to model fluid flow in a gas centrifuge. The governing 6th order partial differential equation is broken down into an equivalent coupled system of three equations and then solved numerically. In addition to a discussion on the baseline solution, known problems and future work possibilities are presented.

  2. Burden distribution control for maintaining the central gas flow at No. 1 blast furnace in Pohang Works

    SciTech Connect (OSTI)

    Jung, S.K.; Lee, Y.J.; Suh, Y.K.; Ahn, T.J.; Kim, S.M. [Pohang Iron and Steel Co. Ltd. (Korea, Republic of). Technical Research Labs.

    1995-12-01T23:59:59.000Z

    The causes for temperature lowering at the upper shaft center in Pohang No. 1 blast furnace were investigated. The test operation with charging notch change in the actual blast furnace and with a 1/12 scale model to Pohang No. 1 blast furnace were carried out in order to improve central gas flow in the shaft. Finally, rebuilding of the lower bunker interior was performed using the results of model experiments. It was confirmed that the main reason for the gas temperature lowering at the upper shaft center was the smaller particle size at center than the wall according to the discharging characteristics of center feed bunker with stone box. The central gas flow could be secured through modifying the stone box in the bunker.

  3. Heat transfer and pressure drop of supercritical carbon dioxide flowing in several printed circuit heat exchanger channel patterns

    SciTech Connect (OSTI)

    Carlson, M. [Univ. of Wisconsin - Madison, 839 Engineering Research Building, 1500 Engineering Drive, Madison, WI 53706 (United States); Kruizenga, A. [Sandia National Laboratory (United States); Anderson, M.; Corradini, M. [Univ. of Wisconsin - Madison, 839 Engineering Research Building, 1500 Engineering Drive, Madison, WI 53706 (United States)

    2012-07-01T23:59:59.000Z

    Closed-loop Brayton cycles using supercritical carbon dioxide (SCO{sub 2}) show potential for use in high-temperature power generation applications including High Temperature Gas Reactors (HTGR) and Sodium-Cooled Fast Reactors (SFR). Compared to Rankine cycles SCO{sub 2} Brayton cycles offer similar or improved efficiency and the potential for decreased capital costs due to a reduction in equipment size and complexity. Compact printed-circuit heat exchangers (PCHE) are being considered as part of several SCO{sub 2} Brayton designs to further reduce equipment size with increased energy density. Several designs plan to use a gas cooler operating near the pseudo-critical point of carbon dioxide to benefit from large variations in thermophysical properties, but further work is needed to validate correlations for heat transfer and pressure-drop characteristics of SCO{sub 2} flows in candidate PCHE channel designs for a variety of operating conditions. This paper presents work on experimental measurements of the heat transfer and pressure drop behavior of miniature channels using carbon dioxide at supercritical pressure. Results from several plate geometries tested in horizontal cooling-mode flow are presented, including a straight semi-circular channel, zigzag channel with a bend angle of 80 degrees, and a channel with a staggered array of extruded airfoil pillars modeled after a NACA 0020 airfoil with an 8.1 mm chord length facing into the flow. Heat transfer coefficients and bulk temperatures are calculated from measured local wall temperatures and local heat fluxes. The experimental results are compared to several methods for estimating the friction factor and Nusselt number of cooling-mode flows at supercritical pressures in millimeter-scale channels. (authors)

  4. Pore-scale mechanisms of gas flow in tight sand reservoirs

    E-Print Network [OSTI]

    Silin, D.

    2011-01-01T23:59:59.000Z

    Potential e?ects of gas hydrate on human welfare, Proc Natlproduction from natural gas hydrates, Energy Economics 31 (Global estimates of hydrate-bound gas in marine sediments:

  5. Computational Fluid Dynamics Modeling of the Bonneville Project: Tailrace Spill Patterns for Low Flows and Corner Collector Smolt Egress

    SciTech Connect (OSTI)

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

    2010-12-01T23:59:59.000Z

    In 2003, an extension of the existing ice and trash sluiceway was added at Bonneville Powerhouse 2 (B2). This extension started at the existing corner collector for the ice and trash sluiceway adjacent to Bonneville Powerhouse 2 and the new sluiceway was extended to the downstream end of Cascade Island. The sluiceway was designed to improve juvenile salmon survival by bypassing turbine passage at B2, and placing these smolt in downstream flowing water minimizing their exposure to fish and avian predators. In this study, a previously developed computational fluid dynamics model was modified and used to characterized tailrace hydraulics and sluiceway egress conditions for low total river flows and low levels of spillway flow. STAR-CD v4.10 was used for seven scenarios of low total river flow and low spill discharges. The simulation results were specifically examined to look at tailrace hydraulics at 5 ft below the tailwater elevation, and streamlines used to compare streamline pathways for streamlines originating in the corner collector outfall and adjacent to the outfall. These streamlines indicated that for all higher spill percentage cases (25% and greater) that streamlines from the corner collector did not approach the shoreline at the downstream end of Bradford Island. For the cases with much larger spill percentages, the streamlines from the corner collector were mid-channel or closer to the Washington shore as they moved downstream. Although at 25% spill at 75 kcfs total river, the total spill volume was sufficient to "cushion" the flow from the corner collector from the Bradford Island shore, areas of recirculation were modeled in the spillway tailrace. However, at the lowest flows and spill percentages, the streamlines from the B2 corner collector pass very close to the Bradford Island shore. In addition, the very flow velocity flows and large areas of recirculation greatly increase potential predator exposure of the spillway passed smolt. If there is concern for egress issues for smolt passing through the spillway, the spill pattern and volume need to be revisited.

  6. Study of Flow Regimes in Multiply-Fractured Horizontal Wells in Tight Gas and Shale Gas Reservoir Systems 

    E-Print Network [OSTI]

    Freeman, Craig M.

    2010-07-14T23:59:59.000Z

    Various analytical, semi-analytical, and empirical models have been proposed to characterize rate and pressure behavior as a function of time in tight/shale gas systems featuring a horizontal well with multiple hydraulic fractures. Despite a small...

  7. Study of Flow Regimes in Multiply-Fractured Horizontal Wells in Tight Gas and Shale Gas Reservoir Systems

    E-Print Network [OSTI]

    Freeman, Craig M.

    2010-07-14T23:59:59.000Z

    Various analytical, semi-analytical, and empirical models have been proposed to characterize rate and pressure behavior as a function of time in tight/shale gas systems featuring a horizontal well with multiple hydraulic fractures. Despite a small...

  8. Morphologies and flow patterns in quenching of lamellar systems with shear

    E-Print Network [OSTI]

    Aiguo Xu; G. Gonnella; A. Lamura

    2005-08-01T23:59:59.000Z

    We study the behavior of a fluid quenched from the disordered into the lamellar phase under the action of a shear flow. The dynamics of the system is described by Navier-Stokes and convection-diffusion equations with pressure tensor and chemical potential derived by the Brazovskii free-energy. Our simulations are based on a mixed numerical method with Lattice Boltzmann equation and finite difference scheme for Navier-Stokes and order parameter equations, respectively. We focus on cases where banded flows are observed with two different slopes for the component of velocity in the direction of the applied flow. Close to the walls the system reaches a lamellar order with very few defects and the slope of the horizontal velocity is higher than the imposed shear rate. In the middle of the system the local shear rate is lower than the imposed one and the system looks as a mixture of tilted lamellae, droplets and small elongated domains. We refer to this as to a region with a Shear Induced Structures (SIS) configuration. The local behavior of the stress shows that the system with the coexisting lamellar and SIS regions is in mechanical equilibrium. This phenomenon occurs, at fixed viscosity, for shear rates under a certain threshold; when the imposed shear rate is sufficiently large, lamellar order develops in the whole system. Effects of different viscosities have been also considered: The SIS region is observed only at low enough viscosity. We compare the above scenario with the usual one of shear banding. In particular, we do not find evidence for a plateau of the stress at varying imposed shear rates in the region with banded flow. We interpret our results as due to a tendency of the lamellar system to oppose to the presence of the applied flow.

  9. Hot gas cleanup using ceramic cross flow membrane filters. Final report

    SciTech Connect (OSTI)

    Ciliberti, D.F.; Smeltzer, E.E.; Alvin, M.A.; Keairns, D.L.; Bachovchin, D.M.

    1983-12-01T23:59:59.000Z

    The single unresolved technical issue in the commercialization of pressurized fluid-bed combustion (PPBC) for electric power production is the hot gas cleaning problem. In this technology, high-temperature and -pressure (HTHP), dust-laden flue gases from the combustor must be cleaned enough to reduce expansion turbine blade erosion to an economically acceptable level. Additionally, the level of particulate emission must be compatible with the New Source Performance Standards (NSPS) for environmental acceptability. The Department of Energy (DOE) has sponsored a wide range of research and development programs directed at the solution of this problem. These programs were divided into two classifications, one dealing with more advanced concepts where testing was to be done at relatively large scale and a second group of less advanced, novel concepts where the testing was to be carried out at a bench scale. The cross-flow ceramic membrane filter program described in this report is a member of the small-scale, novel concept group.

  10. FEMO, A FLOW AND ENRICHMENT MONITOR FOR VERIFYING COMPLIANCE WITH INTERNATIONAL SAFEGUARDS REQUIREMENTS AT A GAS CENTRIFUGE ENRICHMENT FACILITY

    SciTech Connect (OSTI)

    Gunning, John E [ORNL; Laughter, Mark D [ORNL; March-Leuba, Jose A [ORNL

    2008-01-01T23:59:59.000Z

    A number of countries have received construction licenses or are contemplating the construction of large-capacity gas centrifuge enrichment plants (GCEPs). The capability to independently verify nuclear material flows is a key component of international safeguards approaches, and the IAEA does not currently have an approved method to continuously monitor the mass flow of 235U in uranium hexafluoride (UF6) gas streams. Oak Ridge National Laboratory is investigating the development of a flow and enrichment monitor, or FEMO, based on an existing blend-down monitoring system (BDMS). The BDMS was designed to continuously monitor both 235U mass flow and enrichment of UF6 streams at the low pressures similar to those which exists at GCEPs. BDMSs have been installed at three sites-the first unit has operated successfully in an unattended environment for approximately 10 years. To be acceptable to GCEP operators, it is essential that the instrument be installed and maintained without interrupting operations. A means to continuously verify flow as is proposed by FEMO will likely be needed to monitor safeguards at large-capacity plants. This will enable the safeguards effectiveness that currently exists at smaller plants to be maintained at the larger facilities and also has the potential to reduce labor costs associated with inspections at current and future plants. This paper describes the FEMO design requirements, operating capabilities, and development work required before field demonstration.

  11. Development of a new dynamic gas flow-control system in the pressure range of 1 Pa-133 Pa

    SciTech Connect (OSTI)

    Hong, S. S.; Chung, J. W. [Korea Research Institute of Standards and Science, Daejeon 305-340 (Korea, Republic of); Khan, Wakil [Pakistan Vacuum Society, street 17, Islamabad (Pakistan)

    2011-12-15T23:59:59.000Z

    A new flow-control system (FCS-705) has been developed at Korea Research Institute of Standards and Science. The system is intended for calibration of vacuum gauges in the pressure range of 1 Pa-133 Pa by comparison method. This paper describes some basic characteristics of the system including; (1) the design and construction of the system, (2) the generation of stable pressures in the chamber, (3) achieving high upstream pressure limit by installing a short duct in the by-pass pumping line, and (4) investigation of the gas flow regimes within the short duct.

  12. Simulation of Strongly Heated Internal Gas Flows Using a Near-Wall Two-Equation Heat Flux Model

    SciTech Connect (OSTI)

    Richards, Adam H.; Spall, Robert E. [Utah State University, 1400 Old Main Hill Logan, Utah 84322-1400 (United States)

    2006-07-01T23:59:59.000Z

    A two-equation k-{omega} model is used to model a strongly heated, low-Mach number gas flowing upward in a vertical tube. Heating causes significant property variation and thickening of the viscous sublayer, consequently a fully developed flow does not evolve. Two-equation turbulence models generally perform poorly under such conditions. Consequently, in the present work, a near-wall two-equation heat transfer model is utilized in conjunction with the k-{omega} model to improve heat transfer predictions. (authors)

  13. A coupled model for ring dynamics, gas flow, and oil flow through the ring grooves in IC engines

    E-Print Network [OSTI]

    Jia, Ke, S. M. Massachusetts Institute of Technology

    2009-01-01T23:59:59.000Z

    Oil flows through ring/groove interface play a critical role in oil transport among different regions the piston ring pack of internal combustion engines. This thesis work is intended to improve the understanding and ...

  14. Development of active regions: flows, magnetic-field patterns and bordering effect

    E-Print Network [OSTI]

    Getling, A V; Buchnev, A A

    2015-01-01T23:59:59.000Z

    A qualitative analysis is given to the data on the full magnetic and velocity vector fields in a growing sunspot group, recorded nearly simultaneously with the Solar Optical Telescope on the Hinode satellite. Observations of a young bipolar subregion developing within AR 11313 were carried out on 9-10 October 2011. Our aim was to form am idea about the consistency of the observed pattern with the well-known rising-tube model of the formation of bipolar acrive regions and sunspot groups. We find from our magnetograms that the distributions of the vertical [B_v] and the horizontal [B_h] component of the magnetic field over the area of the magnetic subregion are spatially well correlated; in contrast, the rise of a flux-tube loop would result in a qualitatively different pattern, with the maxima of the two magnetic-field components spatially separated: the vertical field would be the strongest where either spot emerges, while the maximum horizontal-field strengths would be reached in between them. A specific fea...

  15. Influence of Atmospheric Pressure and Water Table Fluctuations on Gas Phase Flow and Transport of Volatile Organic Compounds (VOCs) in Unsaturated Zones

    E-Print Network [OSTI]

    You, Kehua

    2013-04-19T23:59:59.000Z

    Understanding the gas phase flow and transport of volatile organic compounds (VOCs) in unsaturated zones is indispensable to develop effective environmental remediation strategies, to create precautions for fresh water protection, and to provide...

  16. Effect of Cooling Flow on the Operation of a Hot Rotor-Gas Foil Bearing System

    E-Print Network [OSTI]

    Ryu, Keun

    2012-02-14T23:59:59.000Z

    .2 Drive end GFB: Predicted bearing static parameters ................................. 157 M.3 Free end GFB: Predicted bearing static parameters ................................... 158 1 CHAPTER I INTRODUCTION Micro gas turbine engines (<400... kW) are light-weight compact units operating at extreme temperatures and at high rotor speeds to achieve the desired power with reduced emissions [1]. Employing gas foil bearings (GFBs) in micro gas turbines increases system efficiency...

  17. Corrosion-induced gas generation in a nuclear waste repository: Reactive geochemistry and multiphase flow effect

    E-Print Network [OSTI]

    Xu, T.

    2009-01-01T23:59:59.000Z

    Lying Repositories for Nuclear Waste, NAGRA Technical Reporthost rock formation for nuclear waste storage. EngineeringGas Generation in a Nuclear Waste Repository: Reactive

  18. 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

  19. Injection, flow, and mixing of CO2 in porous media with residual gas.

    SciTech Connect (OSTI)

    Oldenburg, C.M.; Doughty, C.A.

    2010-09-01T23:59:59.000Z

    Geologic structures associated with depleted natural gas reservoirs are desirable targets for geologic carbon sequestration (GCS) as evidenced by numerous pilot and industrial-scale GCS projects in these environments world-wide. One feature of these GCS targets that may affect injection is the presence of residual CH{sub 4}. It is well known that CH{sub 4} drastically alters supercritical CO{sub 2} density and viscosity. Furthermore, residual gas of any kind affects the relative permeability of the liquid and gas phases, with relative permeability of the gas phase strongly dependent on the time-history of imbibition or drainage, i.e., dependent on hysteretic relative permeability. In this study, the effects of residual CH{sub 4} on supercritical CO{sub 2} injection were investigated by numerical simulation in an idealized one-dimensional system under three scenarios: (1) with no residual gas; (2) with residual supercritical CO{sub 2}; and (3) with residual CH{sub 4}. We further compare results of simulations that use non-hysteretic and hysteretic relative permeability functions. The primary effect of residual gas is to decrease injectivity by decreasing liquid-phase relative permeability. Secondary effects arise from injected gas effectively incorporating residual gas and thereby extending the mobile gas plume relative to cases with no residual gas. Third-order effects arise from gas mixing and associated compositional effects on density that effectively create a larger plume per unit mass. Non-hysteretic models of relative permeability can be used to approximate some parts of the behavior of the system, but fully hysteretic formulations are needed to accurately model the entire system.

  20. Integrated use of burden profile probe and in-burden probe for gas flow control in the blast furnace

    SciTech Connect (OSTI)

    Bordemann, F.; Hartig, W.H. [AG der Dillinger Huettenweke, Dillingen (Germany); Grisse, H.J. [Dango and Dienenthal Siegen (Germany); Speranza, B.E. [Dango and Dienenthal, Inc., Highland, IN (United States)

    1995-12-01T23:59:59.000Z

    Gas flow in the blast furnace is one of the most important factors in controlling a furnace. It not only determines the production but also the fuel consumption and the campaign life. At Nos. 4 and 5 blast furnaces of ROGESA, probes are installed for detection of the burden profiles and of the gas flow distribution. For an optimum use of these probes a program system has been developed by ROGESA and Dango and Dienenthal. With this program system it is possible to analyze the operating condition of a blast furnace by means of a fuzzy logic analysis. In case of deviations from the defined desired condition, recommendations for corrective measures for the material distribution are made. Both furnaces are equipped with a bell-less top, a coal injection system, high-temperature hot blast stoves with heat recovery and a top gas pressure recovery turbine. Most of the time it is impossible to control all the required parameters. For this reason it is meaningful to measure the actual material distribution at the furnace top by means of a burden profile probe which permits quick and repeated measurements without any retroactive effects. The paper describes the instrumentation of the furnace, correlation of measuring methods, and a program system for analysis of measuring data.

  1. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 95, NO. C10, PAGES 18,081-18,094,OCTOBER 15, 1990 Surface Patterns in Temperature, Flow, Phytoplankton Biomass, and Species

    E-Print Network [OSTI]

    Kurapov, Alexander

    Patterns in Temperature, Flow, Phytoplankton Biomass, and Species Composition in the Coastal Transition enriched in phytoplankton biomass, due to the presence of large diatoms. On the seaward side of the front (jet) we observed relatively warm water where the phytoplankton biomass was low and the diatoms were

  2. An analysis of an application of radioactive ionization for gas flow metering

    E-Print Network [OSTI]

    Lam, Carroll Frank

    1959-01-01T23:59:59.000Z

    OF FIGURES CHAP TER I. INTRODUCTION II. EXPERIMENTAL PROCEDURE III. MEASUREMENT OF MARK I CHARACTERISTICS IV. MEASUREMENT OF MARK II CHARACTERISTICS -3 V. CONCLUSIONS . 17 35 BIBLIOGRAPHY . 37 LIST OF FIGURES FIGURE PAGE 1. A Diagram of Rutherford...'s Apparatus Z. An Ezperimental Flow Meter . 3. Mark I Meter and Test Equipment 4. Electrical Circuit 5. Current vs. Flow Rate Curve for Mark I Meter. . . . . . . . . . . . . 6. Current vs. Flow Rate for DifferentSource Spacings. . . . . . . . . . 7...

  3. Virtual Measurement in Pipes, Part 2: Liquid Holdup and Flow Pattern Correlations J. Ternyik, IV, SPE, H.I. Bilgesu, SPE, S. Mohaghegh, SPE, West Virginia U.

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    the design of the system. Other important areas of application can be cited as gas lift operations for the engineer to use in the design process for a variety of conditions. Artificial neural networks (ANN) were multiphase flow systems using readily available data. The VMP methodology was tested for validity

  4. Purged window apparatus. [On-line spectroscopic analysis of gas flow systems

    DOE Patents [OSTI]

    Ballard, E.O.

    1982-04-05T23:59:59.000Z

    A purged window apparatus is described which utilizes tangentially injected heated purge gases in the vicinity of electromagnetic radiation transmitting windows and a tapered external mounting tube to accelerate these gases to provide a vortex flow on the window surface and a turbulent flow throughout the mounting tube thereby preventing backstreaming of flowing gases under investigation in a chamber to which a plurality of similar purged apparatus is attached with the consequent result that spectroscopic analyses can be undertaken for lengthy periods without the necessity of interrupting the flow for cleaning or replacing the windows due to contamination.

  5. The Implications and Flow Behavior of the Hydraulically Fractured Wells in Shale Gas Formation

    E-Print Network [OSTI]

    Almarzooq, Anas Mohammadali S.

    2012-02-14T23:59:59.000Z

    Shale gas formations are known to have low permeability. This low permeability can be as low as 100 nano darcies. Without stimulating wells drilled in the shale gas formations, it is hard to produce them at an economic rate. One of the stimulating...

  6. Coupled multiphase fluid flow and wellbore stability analysis associated with gas production from oceanic hydrate-bearing sediments

    E-Print Network [OSTI]

    Rutqvist, J.

    2014-01-01T23:59:59.000Z

    Toward Production from Gas Hydrates: Current Status,Facing Gas Production From Gas-Hydrate Deposits. Society ofConference on Gas Hydrates (ICGH 2011), Edinburgh, Scotland,

  7. A high sensitivity fiber optic macro-bend based gas flow rate transducer for low flow rates: Theory, working principle, and static calibration

    SciTech Connect (OSTI)

    Schena, Emiliano; Saccomandi, Paola; Silvestri, Sergio [Center for Integrated Research, Unit of Measurements and Biomedical Instrumentation, Universita Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome (Italy)

    2013-02-15T23:59:59.000Z

    A novel fiber optic macro-bend based gas flowmeter for low flow rates is presented. Theoretical analysis of the sensor working principle, design, and static calibration were performed. The measuring system consists of: an optical fiber, a light emitting diode (LED), a Quadrant position sensitive Detector (QD), and an analog electronic circuit for signal processing. The fiber tip undergoes a deflection in the flow, acting like a cantilever. The consequent displacement of light spot center is monitored by the QD generating four unbalanced photocurrents which are function of fiber tip position. The analog electronic circuit processes the photocurrents providing voltage signal proportional to light spot position. A circular target was placed on the fiber in order to increase the sensing surface. Sensor, tested in the measurement range up to 10 l min{sup -1}, shows a discrimination threshold of 2 l min{sup -1}, extremely low fluid dynamic resistance (0.17 Pa min l{sup -1}), and high sensitivity, also at low flow rates (i.e., 33 mV min l{sup -1} up to 4 l min{sup -1} and 98 mV min l{sup -1} from 4 l min{sup -1} up to 10 l min{sup -1}). Experimental results agree with the theoretical predictions. The high sensitivity, along with the reduced dimension and negligible pressure drop, makes the proposed transducer suitable for medical applications in neonatal ventilation.

  8. 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.

  9. An improved multiscale model for dilute turbulent gas particle flows based on the equilibration of energy concept

    SciTech Connect (OSTI)

    Xu, Ying

    2005-05-01T23:59:59.000Z

    Many particle-laden flows in engineering applications involve turbulent gas flows. Modeling multiphase turbulent flows is an important research topic with applications in fluidized beds and particle conveying. A predictive multiphase turbulence model can help CFD codes to be more useful for engineering applications, such as the scale-up in the design of circulating fluidized combustor and coal gasifications. In engineering applications, the particle volume fraction can vary from dilute (<10{sup -4}) to dense ({approx} 50%). It is reasonable to expect that multiphase turbulence models should at least satisfy some basic modeling and performance criteria and give reasonable predictions for the canonical problems in dilute particle-laden turbulent flows. In this research, a comparative assessment of predictions from Simonin and Ahmadi's turbulence models is performed with direct numerical simulation (DNS) for two canonical problems in particle-laden turbulent flows. Based on the comparative assessment, some criteria and the areas for model improvement are identified: (1) model for interphase TKE transfer, especially the time scale of interphase TKE transfer, and (2) correct prediction of TKE evolution with variation of particle Stokes number. Some deficiencies that are identified in the Simonin and Ahmadi models, limit the applicability. A new multiphase turbulence model, the Equilibration of Energy Model (EEM), is proposed in this work. In EEM, a multiscale interaction time scale is proposed to account for the interaction of a particle with a range of eddy sizes. EEM shows good agreement with the DNS results for particle-laden isotropic turbulence. For particle-laden homogeneous shear flows, model predictions from EEM can be further improved if the dissipation rate in fluid phase is modeled with more accuracy.

  10. Fracture Modeling and Flow Behavior in Shale Gas Reservoirs Using Discrete Fracture Networks

    E-Print Network [OSTI]

    Ogbechie, Joachim Nwabunwanne

    2012-02-14T23:59:59.000Z

    Gen and NFflow) for fracture modeling of a shale gas reservoir and also studies the interaction of the different fracture properties on reservoir response. The most important results of the study are that a uniform fracture network distribution and fracture...

  11. The development of a curb valve flow meter for gas theft detection

    E-Print Network [OSTI]

    Fitzgerald, Kevin Francis

    1984-01-01T23:59:59.000Z

    As the supply of natural gas continues to dwindle, and government decontrol of pricing progresses, the rising cost of this essential natural resource will drive more individuals to consider various forms of pilferage as a ...

  12. Gas/slurry flow in coal-liquefaction processes (fluid dynamics in a three-phase-flow column). Final technical progress report, 1 October 1979-31 March 1982

    SciTech Connect (OSTI)

    Ying, D.H.S.; Sivasubramanian, R.; Moujaes, S.F.; Givens, E.N.

    1982-04-01T23:59:59.000Z

    A commercial coal liquefaction plant will employ vertical tubular reactors feeding slurry and gas concurrently upward through these vessels. In the SRC-I plant design the reactor is essentially an empty vessel with only a distributor plate located near the inlet. Because the commercial plant represents a considerable scale-up over Wilsonville or any pilot plant, this program addressed the need for additional data on behavior of three phase systems in large vessels. Parameters that were investigated in this program were studied at conditions that relate directly to projected plant operating conditions. The fluid dynamic behavior of the three-phase upflow system was studied by measuring gas and slurry holdup, liquid dispersion, solids suspension and solids accumulation. The dependent parameters are gas and liquid velocities, solid particle size, solids concentration, liquid viscosity, liquid surface tension and inlet distributor. Within the range of liquid superficial velocity from 0.0 to 0.5 ft/sec, gas holdup is found to be independent of liquid flow which agrees with other investigators. The results also confirm our previous finding that gas holdup is independent of column diameter when the column diameter is 5 inches or larger. The gas holdup depends strongly on gas flow rate; gas holdup increases with increasing gas velocity. The effect of solids particles on gas holdup depends on the gas flow rate. Increasing liquid viscosity and surface tension reduce gas holdup which agrees with other investigators. Because of the complexity of the system, we could not find a single correlation to best fit all the data. The degree of liquid backmixing markedly affects chemical changes occurring in the dissolver, such as sulfur removal, and oil and distillate formation.

  13. INTERNAL FORCED iquid or gas flow through pipes or ducts is commonly used in heating and

    E-Print Network [OSTI]

    Ghajar, Afshin J.

    to flow by a fan or pump through a flow section that is sufficiently long to accomplish the desired heat. Then the logarithmic mean temperature difference and the rate of heat loss from the air become Tln 15.2°C Q · hAs Tln (13.5 W/m2 °C)(6.4 m2 )( 15.2°C) 1313 W Therefore, air will lose heat at a rate of 1313 W as it flows

  14. Application of Crunch-Flow Routines to Constrain Present and Past Carbon Fluxes at Gas-Hydrate Bearing Sites

    SciTech Connect (OSTI)

    Torres, Marta

    2014-01-31T23:59:59.000Z

    In November 2012, Oregon State University initiated the project entitled: Application of Crunch-Flow routines to constrain present and past carbon fluxes at gas-hydrate bearing sites. Within this project we developed Crunch-Flow based modeling modules that include important biogeochemical processes that need to be considered in gas hydrate environments. Our modules were applied to quantify carbon cycling in present and past systems, using data collected during several DOE-supported drilling expeditions, which include the Cascadia margin in US, Ulleung Basin in South Korea, and several sites drilled offshore India on the Bay of Bengal and Andaman Sea. Specifically, we completed modeling efforts that: 1) Reproduce the compositional and isotopic profiles observed at the eight drilled sites in the Ulleung Basin that constrain and contrast the carbon cycling pathways at chimney (high methane flux) and non-chimney sites (low methane, advective systems); 2) Simulate the Ba record in the sediments to quantify the past dynamics of methane flux in the southern Hydrate Ridge, Cascadia margin; and 3) Provide quantitative estimates of the thickness of individual mass transport deposits (MTDs), time elapsed after the MTD event, rate of sulfate reduction in the MTD, and time required to reach a new steady state at several sites drilled in the Krishna-Godavari (K-G) Basin off India. In addition we developed a hybrid model scheme by coupling a home-made MATLAB code with CrunchFlow to address the methane transport and chloride enrichment at the Ulleung Basins chimney sites, and contributed the modeling component to a study focusing on pore-scale controls on gas hydrate distribution in sediments from the Andaman Sea. These efforts resulted in two manuscripts currently under review, and contributed the modeling component of another pare, also under review. Lessons learned from these efforts are the basis of a mini-workshop to be held at Oregon State University (Feb 2014) to instruct graduate students (OSU and UW) as well as DOE staff from the NETL lab in Albany on the use of Crunch Flow for geochemical applications.

  15. Lattice-Boltzmann Simulations of Multiphase Flows in Gas-Diffusion-Layer (GDL) of a PEM Fuel Cell

    SciTech Connect (OSTI)

    Shiladitya Mukherjeea; J. Vernon Cole; Kunal Jainb; Ashok Gidwania

    2008-11-01T23:59:59.000Z

    Improved power density and freeze-thaw durability in automotive applications of Proton Exchange Membrane Fuel Cells (PEMFCs) requires effective water management at the membrane. This is controlled by a porous hydrophobic gas-diffusion-layer (GDL) inserted between the membrane catalyst layer and the gas reactant channels. The GDL distributes the incoming gaseous reactants on the catalyst surface and removes excess water by capillary action. There is, however, limited understanding of the multiphase, multi-component transport of liquid water, vapor and gaseous reactants within these porous materials. This is due primarily to the challenges of in-situ diagnostics for such thin (200 -? 300 {microns}), optically opaque (graphite) materials. Transport is typically analyzed by fitting Darcy's Law type expressions for permeability, in conjunction with capillary pressure relations based on formulations derived for media such as soils. Therefore, there is significant interest in developing predictive models for transport in GDLs and related porous media. Such models could be applied to analyze and optimize systems based on the interactions between cell design, materials, and operating conditions, and could also be applied to evaluating material design concepts. Recently, the Lattice Boltzmann Method (LBM) has emerged as an effective tool in modeling multiphase flows in general, and flows through porous media in particular. This method is based on the solution of a discrete form of the well-known Boltzmann Transport Equation (BTE) for molecular distribution, tailored to recover the continuum Navier-Stokes flow. The kinetic theory basis of the method allows simple implementation of molecular forces responsible for liquid-gas phase separation and capillary effects. The solution advances by a streaming and collision type algorithm that makes it suitable to implement for domains with complex boundaries. We have developed both single and multiphase LB models and applied them to simulate flow through porous GDL materials. We will present an overview of the methods as implemented, verification studies for both microstructure reconstruction and transport simulations, and application to single- and two-phase transport in GDL structures. The applications studies are designed to both improve understanding of transport within a given structure, and to investigate possible routes for improving material properties through microstructure design.

  16. Basic research model of gas combustion in turbulent flow. Annual report, 1 June 1988-30 June 1989

    SciTech Connect (OSTI)

    Dahm, W.J.A.; Tryggvason, G.; Krasny, R.

    1989-01-01T23:59:59.000Z

    The report describes the development currently underway of a basic research model for gas combustion in turbulent flow. The model being developed is fundamentally different from the conventional types of turbulence models currently in use for flame calculations, both in terms of the underlying physical approximations made and in the numerical techniques used to implement them. The present approach is based on the idea that many of the precise and detailed fine scale processes at work in turbulent combustion have a simple self-similar structure, and as a result do not need to be continually recomputed in full detail. These can be modeled using results from recent experimental research into the fine scales of turbulent flows. Results obtained to date from this model have been carefully compared with finite difference simulations of the full governing equations for several simple test cases, and show that even complex and highly nonlinear phenomena such as local extinction of reactions in the flow field are correctly reproduced by the model. The model directly incorporates the strong coupling between the fluid dynamics and combustion chemistry in the flame. Work presently underway is incorporating volume source effects into the model.

  17. 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

  18. Coupled flow and geomechanical analysis for gas production in the Prudhoe Bay Unit L-106 well Unit C gas hydrate deposit in Alaska

    E-Print Network [OSTI]

    Kim, J.

    2014-01-01T23:59:59.000Z

    2009. Toward Production From Gas Hydrates: Current Status,Geologic Controls on Gas Hydrate Occurrence in the MountCollett T.S. 1993. Natural Gas Hydrates of the Prudhoe Bay

  19. On the full lagrangian approach and thermophoretic deposition in gas-particle flows

    E-Print Network [OSTI]

    Healy, David Patrick

    2003-11-25T23:59:59.000Z

    to impose a radial temperature difference in pipe flow experiments, but have not yet succeeded in attaining a constant thermophoretic force along the length of the pipe. This limits the accuracy and usefulness of the data for the validation of theoretical...

  20. 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.

  1. Hydrodynamic flow in lower Cretaceous Muddy sandstone, Gas Draw Field, Powder River Basin, Wyoming

    E-Print Network [OSTI]

    Lin, Joseph Tien-Chin

    1978-01-01T23:59:59.000Z

    control readily available for analysis of rock properties and fluid pressures. The nine-township area surrounding the Gas Draw field is well-suited for study of hydrodynamic effects on oil accumulation. Regional Geology Structure The citations... of southeastern Montana. It is bounded by the Miles City arch and Black Hills uplift on the east, the Hartville uplift on the southeast, and Bighorn Mountains and Casper arch on the west. Muddy stratigraphic oil fields are located on the east flank...

  2. Impact of relative permeability models on fluid flow behavior for gas condensate reservoirs

    E-Print Network [OSTI]

    Zapata Arango, Jose? Francisco

    2002-01-01T23:59:59.000Z

    . 6 Integral from immiscible to miscible transition models for gas condensate relative permeability. 5 . 6 . . 8 9 . 10 . 12 . 16 . 18 . 20 . 23 CHAPTER III CASE STUDY. . . 27 3. 1 Tuning of the reservoir fluid model 3. 2 Relative... model . 5. 2. 2 Anisotropic model . 64 . 74 . 77 . 90 CHAPTER VI SUMMARY . 105 6. 1 Conclusions. . 6. 1. 1 Conclusions from the literature review and case study . . . . . . 6. 1. 2 Conclusions from the simulation study 6. 1. 3 Conclusions from...

  3. Impact of relative permeability models on fluid flow behavior for gas condensate reservoirs 

    E-Print Network [OSTI]

    Zapata Arango, Jose? Francisco

    2002-01-01T23:59:59.000Z

    . 6 Integral from immiscible to miscible transition models for gas condensate relative permeability. 5 . 6 . . 8 9 . 10 . 12 . 16 . 18 . 20 . 23 CHAPTER III CASE STUDY. . . 27 3. 1 Tuning of the reservoir fluid model 3. 2 Relative... model . 5. 2. 2 Anisotropic model . 64 . 74 . 77 . 90 CHAPTER VI SUMMARY . 105 6. 1 Conclusions. . 6. 1. 1 Conclusions from the literature review and case study . . . . . . 6. 1. 2 Conclusions from the simulation study 6. 1. 3 Conclusions from...

  4. Coupled flow and geomechanical analysis for gas production in the Prudhoe Bay Unit L-106 well Unit C gas hydrate deposit in Alaska

    E-Print Network [OSTI]

    Kim, J.

    2014-01-01T23:59:59.000Z

    way Coupled Fluid Flow and Geomechanics in Hydrate Deposits.for Coupled Flow and Geomechanics. Soc. Pet. Eng. J. 16(2):for coupled flow and geomechanics: Drained and undrained

  5. Modal Wavelets Analysis to Gas-Liquid Two Phase Flow PIV Images

    SciTech Connect (OSTI)

    Masahiro Takei [Nihon University, 1866 Kameino, Fujisawa-Shi, Kanagawa 252-8510 (Japan); Hassan, Yassin A. [Texas A and M University, College Station, Texas 77843 (United States); Ortiz-Villafuerte, J. [National Institute for Nuclear Research, Carretera Mexico Toluca Km.36.5, 52045 Municipio de Ocoyoacac, Salazar. Edo. de Mexico, C.P.52046 Mexico (Mexico); Tomomasa Uemura [Kansai University, Suita-shi, Osaka 564 (Japan)

    2006-07-01T23:59:59.000Z

    A modal wavelet transform, which overcomes the intrinsic data number limitation of power of two to conventional wavelet transform, has been applied to analysis of pseudo and real bubbly flow PIV images. The modal wavelet transform is compared with the discrete wavelet transform in order to select the best base function among Neumann, Dirichlet and Green function types base functions. Consequently, it is verified that Neumann type base function is the best because the correlation of Neumann type base function is the highest. From the result of wavelet analysis of the real bubbly flow PIV image, as the relative velocity is higher, the dominant eddy scale becomes smaller. The extraction modal wavelet level depends on the base function. (authors)

  6. DESIGN AND DEVELOPMENT OF GAS-LIQUID CYLINDRICAL CYCLONE COMPACT SEPARATORS FOR THREE-PHASE FLOW

    SciTech Connect (OSTI)

    Dr. Ram S. Mohan; Dr. Ovadia Shoham

    2001-04-30T23:59:59.000Z

    This report presents a brief overview of the activities and tasks accomplished during the first half year (October 1, 2000-March 31, 2001) of the fourth project year budget period (October 1, 2000-September 30, 2001). An executive summary is presented initially followed by the tasks of the current budget period. Then, detailed description of the experimental and modeling investigations are presented. Subsequently, the technical and scientific results of the activities of this project period are presented with some discussions. The findings of this investigation are summarized in the ''Conclusions'' section followed by relevant references. The fourth project year activities are divided into three main parts, which are carried out in parallel. The first part is continuation of the experimental program that includes a study of the oil/water two-phase behavior at high pressures and control system development for the three-phase GLCC{copyright}. This investigation will be eventually extended for three-phase flow. The second part consists of the development of a simplified mechanistic model incorporating the experimental results and behavior of dispersion of oil in water and water in oil. This will provide an insight into the hydrodynamic flow behavior and serve as the design tool for the industry. Although useful for sizing GLCC{copyright} for proven applications, the mechanistic model will not provide detailed hydrodynamic flow behavior information needed to screen new geometric variations or to study the effect of fluid property variations. Therefore, in the third part, the more rigorous approach of computational fluid dynamics (CFD) will be utilized. Multidimensional multiphase flow simulation at high pressures and for real crude conditions will provide much greater depth into the understanding of the physical phenomena and the mathematical analysis of three-phase GLCC{copyright} design and performance.

  7. Apparatus for measuring the local void fraction in a flowing liquid containing a gas

    DOE Patents [OSTI]

    Dunn, Patrick F. (Downers Grove, IL)

    1981-01-01T23:59:59.000Z

    The local void fraction in liquid containing a gas is measured by placing an impedance-variation probe in the liquid, applying a controlled voltage or current to the probe, and measuring the probe current or voltage. A circuit for applying the one electrical parameter and measuring the other includes a feedback amplifier that minimizes the effect of probe capacitance and a digitizer to provide a clean signal. Time integration of the signal provides a measure of the void fraction, and an oscilloscope display also shows bubble size and distribution.

  8. Galaxy gas flows inferred from a detailed, spatially resolved metal budget

    E-Print Network [OSTI]

    Belfiore, F; Bothwell, M

    2015-01-01T23:59:59.000Z

    We use the most extensive integral field spectroscopic map of a local galaxy, NGC 628, combined with gas and stellar mass surface density maps, to study the distribution of metals in this galaxy out to 3 effective radii ($\\rm R_e$). At each galactocentric distance, we compute the metal budget and thus constrain the mass of metals lost. We find that in the disc about half of the metals have been lost throughout the lifetime of the galaxy. The fraction of metals lost is higher in the bulge ($\\sim$70%) and decreases towards the outer disc ($\\rm \\sim 3 \\ R_e$). In contrast to studies based on the gas kinematics, which are only sensitive to ongoing outflow events, our metal budget analysis enables us to infer the average outflow rate during the galaxy lifetime. By using simple physically motivated models of chemical evolution we can fit the observed metal budget at most radii with an average outflow loading factor of order unity, thus clearly demonstrating the importance of outflows in the evolution of disc galaxi...

  9. Effect of N2 /Ar gas flow ratio on the deposition of TiN/Ti coatings on NiTi shape memory alloy by PIIID

    E-Print Network [OSTI]

    Zheng, Yufeng

    and deposition technique. The effect of nitrogen to argon gas flow ratio on the surface characteristics, chemical in standard uncoated titanium implants [7]. To date, NiTi alloy has found numerous clinical applica- tions. The nitrogen to argon ratio was changed in order to obtain the stoichiometric TiN coating. The surface

  10. Influence of Gas Flow Rate for Formation of Aligned Nanorods in ZnO Thin Films for Solar-Driven Hydrogen Production

    SciTech Connect (OSTI)

    Shet, S.; Chen, L.; Tang, H.; Nuggehalli, R.; Wang, H.; Yan, Y.; Turner, J.; Al-Jassim, M.

    2012-04-01T23:59:59.000Z

    ZnO thin films have been deposited in mixed Ar/N{sub 2} gas ambient at substrate temperature of 500 C by radiofrequency sputtering of ZnO targets. We find that an optimum N{sub 2}-to-Ar ratio in the deposition ambient promotes the formation of well-aligned nanorods. ZnO thin films grown in ambient with 25% N{sub 2} gas flow rate promoted nanorods aligned along c-axis and exhibit significantly enhanced photoelectrochemical (PEC) response, compared with ZnO thin films grown in an ambient with different N{sub 2}-to-Ar gas flow ratios. Our results suggest that chamber ambient is critical for the formation of aligned nanostructures, which offer potential advantages for improving the efficiency of PEC water splitting for H{sub 2} production.

  11. Coupled multiphase fluid flow and wellbore stability analysis associated with gas production from oceanic hydrate-bearing sediments

    E-Print Network [OSTI]

    Rutqvist, J.

    2014-01-01T23:59:59.000Z

    and arctic onshore gas hydrate production wells. OTC-21015.Bay Unit L-106 Well Unit C gas hydrate deposit in Alaska.Toward Production from Gas Hydrates: Current Status,

  12. Development of Millimeter-Wave Velocimetry and Acoustic Time-of-Flight Tomography for Measurements in Densely Loaded Gas-Solid Riser Flow

    SciTech Connect (OSTI)

    Fort, James A.; Pfund, David M.; Sheen, David M.; Pappas, Richard A.; Morgen, Gerald P.

    2007-04-01T23:59:59.000Z

    The MFDRC was formed in 1998 to advance the state-of-the-art in simulating multiphase turbulent flows by developing advanced computational models for gas-solid flows that are experimentally validated over a wide range of industrially relevant conditions. The goal was to transfer the resulting validated models to interested US commercial CFD software vendors, who would then propagate the models as part of new code versions to their customers in the US chemical industry. Since the lack of detailed data sets at industrially relevant conditions is the major roadblock to developing and validating multiphase turbulence models, a significant component of the work involved flow measurements on an industrial-scale riser contributed by Westinghouse, which was subsequently installed at SNL. Model comparisons were performed against these datasets by LANL. A parallel Office of Industrial Technology (OIT) project within the consortium made similar comparisons between riser measurements and models at NETL. Measured flow quantities of interest included volume fraction, velocity, and velocity-fluctuation profiles for both gas and solid phases at various locations in the riser. Some additional techniques were required for these measurements beyond what was currently available. PNNL’s role on the project was to work with the SNL experimental team to develop and test two new measurement techniques, acoustic tomography and millimeter-wave velocimetry. Acoustic tomography is a promising technique for gas-solid flow measurements in risers and PNNL has substantial related experience in this area. PNNL is also active in developing millimeter wave imaging techniques, and this technology presents an additional approach to make desired measurements. PNNL supported the advanced diagnostics development part of this project by evaluating these techniques and then by adapting and developing the selected technology to bulk gas-solids flows and by implementing them for testing in the SNL riser testbed.

  13. 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.

  14. Investigation of the Effect of Non-Darcy Flow and Multi-Phase Flow on the Productivity of Hydraulically Fractured Gas Wells

    E-Print Network [OSTI]

    Alarbi, Nasraldin Abdulslam A.

    2011-10-21T23:59:59.000Z

    an optimum stimulation treatment that leads to the maximum possible productivity. These considerations include, but not limited to, non-Darcy flow and multiphase flow effects inside the fracture. These effects reduce the fracture conductivity significantly...

  15. Charged particle's $p_T$ spectra and elliptic flow in $\\sqrt{s_{NN}}$=200 GeV Au+Au collisions: QGP vs. hadronic resonance gas

    E-Print Network [OSTI]

    Chaudhuri, A K

    2010-01-01T23:59:59.000Z

    We show that if the hadronic resonance gas (HRG), with viscosity to entropy ratio $\\eta/s\\approx$0.24, is physical at temperature $T\\approx$220 MeV, charged particles $p_T$ spectra and elliptic flow in Au+Au collisions at RHIC, over a wide range of collision centrality do not distinguish between initial QGP fluid and initial hadronic resonance gas. Unambiguous identification of bulk of the matter produced in Au+Au collisions require clear demonstration that HRG is unphysical at temperature $T<$200 MeV. It calls for precise lattice simulations with realistic boundary conditions.

  16. A unified gas-kinetic scheme for continuum and rarefied flows Kun Xu a,*, Juan-Chen Huang b

    E-Print Network [OSTI]

    Xu, Kun

    a Mathematics Department, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong b makes these methods useless in the continuum flow regime, especially in the high Reynolds number flow

  17. 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 ...

  18. Simultaneous solution algorithms for Eulerian-Eulerian gas-solid flow models: Stability analysis and convergence behaviour of a point and a plane solver

    SciTech Connect (OSTI)

    Wilde, Juray de [Laboratorium voor Petrochemische Techniek, Ghent University, Krijgslaan 281, Blok S5, B-9000 Ghent (Belgium) and Fluid Mechanics Laboratory, Department of Fluid, Heat and Combustion Mechanics, Ghent University, St.-Pietersnieuwstraat 41, B-9000 Ghent (Belgium)]. E-mail: Guray.Marin@UGent.be; Vierendeels, Jan [Fluid Mechanics Laboratory, Department of Fluid, Heat and Combustion Mechanics, Ghent University, St.-Pietersnieuwstraat 41, B-9000 Ghent (Belgium); Heynderickx, Geraldine J. [Laboratorium voor Petrochemische Techniek, Ghent University, Krijgslaan 281, Blok S5, B-9000 Ghent (Belgium); Marin, Guy B. [Laboratorium voor Petrochemische Techniek, Ghent University, Krijgslaan 281, Blok S5, B-9000 Ghent (Belgium)

    2005-07-20T23:59:59.000Z

    Simultaneous solution algorithms for Eulerian-Eulerian gas-solid flow models are presented and their stability analyzed. The integration algorithms are based on dual-time stepping with fourth-order Runge-Kutta in pseudo-time. The domain is solved point or plane wise. The discretization of the inviscid terms is based on a low-Mach limit of the multi-phase preconditioned advection upstream splitting method (MP-AUSMP). The numerical stability of the simultaneous solution algorithms is analyzed in 2D with the Fourier method. Stability results are compared with the convergence behaviour of 3D riser simulations. The impact of the grid aspect ratio, preconditioning, artificial dissipation, and the treatment of the source terms is investigated. A particular advantage of the simultaneous solution algorithms is that they allow a fully implicit treatment of the source terms which are of crucial importance for the Eulerian-Eulerian gas-solid flow models and their solution. The numerical stability of the optimal simultaneous solution algorithm is analyzed for different solids volume fractions and gas-solid slip velocities. Furthermore, the effect of the grid resolution on the convergence behaviour and the simulation results is investigated. Finally, simulations of the bottom zone of a pilot-scale riser with a side solids inlet are experimentally validated.

  19. PARTICLE TRANSPORTATION AND DEPOSITION IN HOT GAS FILTER VESSELS - A COMPUTATIONAL AND EXPERIMENTAL MODELING APPROACH

    SciTech Connect (OSTI)

    Goodarz Ahmadi

    2002-07-01T23:59:59.000Z

    In this project, a computational modeling approach for analyzing flow and ash transport and deposition in filter vessels was developed. An Eulerian-Lagrangian formulation for studying hot-gas filtration process was established. The approach uses an Eulerian analysis of gas flows in the filter vessel, and makes use of the Lagrangian trajectory analysis for the particle transport and deposition. Particular attention was given to the Siemens-Westinghouse filter vessel at Power System Development Facility in Wilsonville in Alabama. Details of hot-gas flow in this tangential flow filter vessel are evaluated. The simulation results show that the rapidly rotation flow in the spacing between the shroud and the vessel refractory acts as cyclone that leads to the removal of a large fraction of the larger particles from the gas stream. Several alternate designs for the filter vessel are considered. These include a vessel with a short shroud, a filter vessel with no shroud and a vessel with a deflector plate. The hot-gas flow and particle transport and deposition in various vessels are evaluated. The deposition patterns in various vessels are compared. It is shown that certain filter vessel designs allow for the large particles to remain suspended in the gas stream and to deposit on the filters. The presence of the larger particles in the filter cake leads to lower mechanical strength thus allowing for the back-pulse process to more easily remove the filter cake. A laboratory-scale filter vessel for testing the cold flow condition was designed and fabricated. A laser-based flow visualization technique is used and the gas flow condition in the laboratory-scale vessel was experimental studied. A computer model for the experimental vessel was also developed and the gas flow and particle transport patterns are evaluated.

  20. Preferential mode of gas invasion in sediments : grain-scale model of coupled multiphase fluid flow and sediment mechanics

    E-Print Network [OSTI]

    Jain, Antone Kumar

    2009-01-01T23:59:59.000Z

    We present a discrete element model for simulating, at the grain scale, gas migration in brine-saturated deformable media. We rigorously account for the presence of two fluids in the pore space by incorporating forces on ...

  1. Cooling design of large capacity gas insulated transformer

    SciTech Connect (OSTI)

    Kawano, Koichiro; Biswas, Debasis; Ishizuka, Masaru; Muramatsu, Koji; Nakadate, Masumi; Toda, Katsutoshi [Toshiba Corp., Kawasaki (Japan)

    1995-12-31T23:59:59.000Z

    From the view point of safety and maintenance simplicity, the development of large capacity gas insulated transformer has been desirable. In this type of transformer, the coolant gas is circulated in the gap between the coils to cool it. The flow pattern of coolant in the flow path strongly depend on its configuration formed by the coil. Therefore, in order to achieve high cooling efficiency of coils and at the same time to reduce the pressure loss, it is important to have sufficient knowledge about the flow behavior in the coil flow path. In the present work, in order to improve the coil cooling efficiency, appropriate flow path configuration were decided on the basis of numerical simulation using various coil configuration and validity of the computed results were tested by comparing with experimental data.

  2. CFD Analysis of Core Bypass Flow and Crossflow in the Prismatic Very High Temperature Gas-cooled Nuclear Reactor 

    E-Print Network [OSTI]

    Wang, Huhu 1985-

    2012-12-13T23:59:59.000Z

    Very High Temperature Rector (VHTR) had been designated as one of those promising reactors for the Next Generation (IV) Nuclear Plant (NGNP). For a prismatic core VHTR, one of the most crucial design considerations is the bypass flow and crossflow...

  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. 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.

  5. Recirculating rotary gas compressor

    DOE Patents [OSTI]

    Weinbrecht, J.F.

    1992-02-25T23:59:59.000Z

    A positive displacement, recirculating Roots-type rotary gas compressor is described which operates on the basis of flow work compression. The compressor includes a pair of large diameter recirculation conduits which return compressed discharge gas to the compressor housing, where it is mixed with low pressure inlet gas, thereby minimizing adiabatic heating of the gas. The compressor includes a pair of involutely lobed impellers and an associated port configuration which together result in uninterrupted flow of recirculation gas. The large diameter recirculation conduits equalize gas flow velocities within the compressor and minimize gas flow losses. The compressor is particularly suited to applications requiring sustained operation at higher gas compression ratios than have previously been feasible with rotary pumps, and is particularly applicable to refrigeration or other applications requiring condensation of a vapor. 12 figs.

  6. Recirculating rotary gas compressor

    DOE Patents [OSTI]

    Weinbrecht, John F. (601 Oakwood Loop, NE., Albuquerque, NM 87123)

    1992-01-01T23:59:59.000Z

    A positive displacement, recirculating Roots-type rotary gas compressor which operates on the basis of flow work compression. The compressor includes a pair of large diameter recirculation conduits (24 and 26) which return compressed discharge gas to the compressor housing (14), where it is mixed with low pressure inlet gas, thereby minimizing adiabatic heating of the gas. The compressor includes a pair of involutely lobed impellers (10 and 12) and an associated port configuration which together result in uninterrupted flow of recirculation gas. The large diameter recirculation conduits equalize gas flow velocities within the compressor and minimize gas flow losses. The compressor is particularly suited to applications requiring sustained operation at higher gas compression ratios than have previously been feasible with rotary pumps, and is particularly applicable to refrigeration or other applications requiring condensation of a vapor.

  7. Predictions of flow and heat transfer in sharp 180-deg turns of gas turbine coolant channels with and without turning vanes

    SciTech Connect (OSTI)

    Bonhoff, B.; Leusch, J.; Johnson, B.V.

    1999-07-01T23:59:59.000Z

    A numerical study was conducted to determine the effects of turning vanes on the flow characteristics, the pressure drop and the heat transfer distribution in the turn region of two-legged, coolant passages for application to cooling gas turbine blades. The channels consisted of two straight, square-sectioned legs connected by a 180-deg. turn, with an inner radius of 0.15 hydraulic diameters. The ribs were square-sectioned with a height of 0.1 D{sub h}, staggered between leading and trailing side and at an angle of 45-deg. to the flow. Three different configurations of the coolant channel were investigated: with smooth walls, with ribs on two walls and no vane and with ribs on two walls and a 180-deg guide vane in the turn. For all calculations, the Reynolds number at the inlet was Re{sub D} = 100,000, the fluid was water and buoyancy effects were neglected. The simulations were made for rotation numbers, Ro = 0.0 and 0.15. The flow and heat transfer simulations were made with the FLUENT structured code. Based on the results of several previous studies, the differential-Reynolds-Stress turbulence model with wall functions was used. The highest heat transfer in the turn was obtained for both the rotating and non-rotating cases with the ribbed channel without the guide vane. The pressure loss was also higher without the vane. Due to the staggering of the ribs, secondary flow and heat transfer in the turn was higher on the side of the channel where the last rib at the entrance reaches further into the turn. With increasing rotation number, the secondary flow and heat transfer increased on the leading side of the turn. For the configuration with a 180-deg. vane, the mass flux at the outer side of the vane increased with increasing rotation number.

  8. 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 ...

  9. Onset and Subsequent Transient Phenomena of Liquid Loading in Gas Wells: Experimental Investigation Using a Large Scale Flow Loop

    E-Print Network [OSTI]

    Waltrich, Paulo

    2012-10-19T23:59:59.000Z

    Liquid loading in gas wells is generally described as the inability of the well to lift the co-produced liquids up the tubing, which may ultimately kill the well. There is a lack of dedicated models that can mimic the transient features...

  10. characterization and visualization of two-phase flow properties of gas diffusion layers used in a PEM fuel cell

    E-Print Network [OSTI]

    Gao, Yan

    2011-04-26T23:59:59.000Z

    the capillary pressure and liquid water saturation for two commercial gas diffusion materials, Toray TGP-H-090 and Toray TGP-H-060. The impact of channel-rib structure on capillary properties of GDLs was investigated by two different configurations...

  11. Optimal fracture treatment design for dry gas wells maximizes well performance in the presence of non-Darcy flow effects

    E-Print Network [OSTI]

    Lopez Hernandez, Henry De Jesus

    2004-11-15T23:59:59.000Z

    to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 2004 Major Subject: Petroleum Engineering...) _______________________________ Guy L. Curry (Member) _______________________________ Stephen A. Holditch (Head of Department) August 2004 Major Subject: Petroleum Engineering iii ABSTRACT Optimal Fracture Treatment Design for Dry Gas Wells Maximizes...

  12. 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.

  13. Experimental study of a shock accelerated thin gas layer

    SciTech Connect (OSTI)

    Jacobs, J.W. [Arizona Univ., Tucson, AZ (United States). Dept. of Aerospace and Mechanical Engineering; Jenkins, D.G.; Klein, D.L.; Benjamin, R.F. [Los Alamos National Lab., NM (United States)

    1993-08-01T23:59:59.000Z

    Planar laser-induced fluorescence imaging is utilized in shock-tube experiments to visualize the development of a shock-accelerated thin gas layer. The Richtmyer-Meshkov instability of both sides of the heavy gas layer causes perturbations initially imposed on the two interfaces to develop into one of three distinct flow patterns. Two of the patterns exhibit vortex pairs which travel either upstream or downstream in the shock tube, while the third is a sinuous pattern that shows no vortex development until late in its evolution. The development of the observed patterns as well as the growth in the layer thickness is modeled by considering the dynamics of vorticity deposited in the layer by the shock interaction process. This model yields an expression for the layer growth which is in good agreement with measurements.

  14. Numerical Simulation of Flow and Heat Transfer in Internal Multi-Pass Cooling Channel within Gas Turbine Blade

    E-Print Network [OSTI]

    Chu, Hung-Chieh 1979-

    2012-11-16T23:59:59.000Z

    four-pass channel with two different inlet settings. The main flowing channel was rectangular channel (AR=2:1) with hydraulic diameter (Dh ) equals to 2/3 inch (16.9 mm). The first and fourth channel were set as different aspect ratio (AR=2:1; AR=1...

  15. CFD Analysis of Core Bypass Flow and Crossflow in the Prismatic Very High Temperature Gas-cooled Nuclear Reactor

    E-Print Network [OSTI]

    Wang, Huhu 1985-

    2012-12-13T23:59:59.000Z

    if the large portion of the coolant flows into bypass gaps instead of coolant channels in which the cooling efficiency is much higher. A preliminary three dimensional steady-state CFD analysis was performed with commercial code STARCCM+ 6.04 to investigate...

  16. Novel selective surface flow (SSF{sup TM}) membranes for the recovery of hydrogren from waste gas streams. Final report

    SciTech Connect (OSTI)

    Anand, M. [USDOE, Washington, DC (United States)

    1995-08-01T23:59:59.000Z

    The waste streams are off-gas streams from various chemical/refinery operations. In Phase I, the architecture of the membrane and the separation device were defined and demonstrated. The system consists of a shell-and-tube separator in which the gas to be separated is fed to the tube side, the product is collected as high pressure effluent and the permeate constitutes the waste/fuel stream. Each tube, which has the membrane coated on the interior, does the separation. A multi- tube separator device containing 1 ft{sup 2} membrane area was built and tested. The engineering data were used for designing a process for hydrogen recovery from a fluid catalytic cracker off-gas stream. First-pass economics showed that overall cost for hydrogen production is reduced by 35% vs on-purpose production of hydrogen by steam- methane reforming. The hydrogen recovery process using the SSF membrane results in at least 15% energy reduction and significant decrease in CO{sub 2} and NO{sub x} emissions.

  17. Basic research model of natural gas combustion in turbulent flow. Phase 2, Annual report, 1 August 1991-31 July 1992

    SciTech Connect (OSTI)

    Dahm, W.J.A.; Tryggvason, G.; Krasny, R.

    1992-09-30T23:59:59.000Z

    The report describes progress made in the past twelve months in developing a local integral method (LIM) model for numerically simulating natural gas mixing and combustion in complex flames. The LIM model is fundamentally different from conventional approaches for numerically simulating combustion in turbulent flames. It is based on the experimental observation that the strain-diffusion balance which establishes the mixing and reaction scales in turbulent flames leads to a self-similar internal structure in the diffusion-reaction layers which does not need to be continually re-computed. Instead, these diffusion and reaction scales are represented by a set of self-similar profile shapes whose moments are allowed to evolve freely to satisfy the governing equations. The resulting LIM computations thus need only follow the evolution of material surface in the flow, and then solve ODE's (ordinary differential equations) on the surface, rather than PDE's (partial differential equations) throughout the whole flame. Results obtained to date show that the model is capable of correctly predicting even highly sensitive non-linear characteristics associated with the combustion processes in turbulent natural gas flames, including the local flame extinction phenomenon in large Zeldovich number Arrhenius kinetics. The simplicity of the LIM technique allows large reductions in computational time in comparison with traditional computational approaches, thus allowing far more complex reaction chemistry to be addressed, as well as ranges of Reynolds, Schmidt and Damkohler numbers which are otherwise completely inaccessible to simulation.

  18. Understanding the dynamics of a two-phase flow (liquid and gas) has been studied quite extensively over the past. This problem is indeed of direct relevance for many areas such

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    be trapped on the ground because of the presence of an obstacle. The studied products were propane, butane set-up, and pressure storage. 1 INTRODUCTION In many chemical and process plants, gas are stored for the understanding of the flow inside the pipe. The net of pipes linking the storage and the nozzle are composed

  19. Static gas expansion cooler

    DOE Patents [OSTI]

    Guzek, J.C.; Lujan, R.A.

    1984-01-01T23:59:59.000Z

    Disclosed is a cooler for television cameras and other temperature sensitive equipment. The cooler uses compressed gas ehich is accelerated to a high velocity by passing it through flow passageways having nozzle portions which expand the gas. This acceleration and expansion causes the gas to undergo a decrease in temperature thereby cooling the cooler body and adjacent temperature sensitive equipment.

  20. A constitutive law for dense granular flows

    E-Print Network [OSTI]

    Pierre Jop; Yoël Forterre; Olivier Pouliquen

    2006-12-05T23:59:59.000Z

    A continuum description of granular flows would be of considerable help in predicting natural geophysical hazards or in designing industrial processes. However, the constitutive equations for dry granular flows, which govern how the material moves under shear, are still a matter of debate. One difficulty is that grains can behave like a solid (in a sand pile), a liquid (when poured from a silo) or a gas (when strongly agitated). For the two extreme regimes, constitutive equations have been proposed based on kinetic theory for collisional rapid flows, and soil mechanics for slow plastic flows. However, the intermediate dense regime, where the granular material flows like a liquid, still lacks a unified view and has motivated many studies over the past decade. The main characteristics of granular liquids are: a yield criterion (a critical shear stress below which flow is not possible) and a complex dependence on shear rate when flowing. In this sense, granular matter shares similarities with classical visco-plastic fluids such as Bingham fluids. Here we propose a new constitutive relation for dense granular flows, inspired by this analogy and recent numerical and experimental work. We then test our three-dimensional (3D) model through experiments on granular flows on a pile between rough sidewalls, in which a complex 3D flow pattern develops. We show that, without any fitting parameter, the model gives quantitative predictions for the flow shape and velocity profiles. Our results support the idea that a simple visco-plastic approach can quantitatively capture granular flow properties, and could serve as a basic tool for modelling more complex flows in geophysical or industrial applications.

  1. Study of Particle Rotation Effect in Gas-Solid Flows using Direct Numerical Simulation with a Lattice Boltzmann Method

    SciTech Connect (OSTI)

    Kwon, Kyung; Fan, Liang-Shih; Zhou, Qiang; Yang, Hui

    2014-09-30T23:59:59.000Z

    A new and efficient direct numerical method with second-order convergence accuracy was developed for fully resolved simulations of incompressible viscous flows laden with rigid particles. The method combines the state-of-the-art immersed boundary method (IBM), the multi-direct forcing method, and the lattice Boltzmann method (LBM). First, the multi-direct forcing method is adopted in the improved IBM to better approximate the no-slip/no-penetration (ns/np) condition on the surface of particles. Second, a slight retraction of the Lagrangian grid from the surface towards the interior of particles with a fraction of the Eulerian grid spacing helps increase the convergence accuracy of the method. An over-relaxation technique in the procedure of multi-direct forcing method and the classical fourth order Runge-Kutta scheme in the coupled fluid-particle interaction were applied. The use of the classical fourth order Runge-Kutta scheme helps the overall IB-LBM achieve the second order accuracy and provides more accurate predictions of the translational and rotational motion of particles. The preexistent code with the first-order convergence rate is updated so that the updated new code can resolve the translational and rotational motion of particles with the second-order convergence rate. The updated code has been validated with several benchmark applications. The efficiency of IBM and thus the efficiency of IB-LBM were improved by reducing the number of the Lagragian markers on particles by using a new formula for the number of Lagrangian markers on particle surfaces. The immersed boundary-lattice Boltzmann method (IBLBM) has been shown to predict correctly the angular velocity of a particle. Prior to examining drag force exerted on a cluster of particles, the updated IB-LBM code along with the new formula for the number of Lagrangian markers has been further validated by solving several theoretical problems. Moreover, the unsteadiness of the drag force is examined when a fluid is accelerated from rest by a constant average pressure gradient toward a steady Stokes flow. The simulation results agree well with the theories for the short- and long-time behavior of the drag force. Flows through non-rotational and rotational spheres in simple cubic arrays and random arrays are simulated over the entire range of packing fractions, and both low and moderate particle Reynolds numbers to compare the simulated results with the literature results and develop a new drag force formula, a new lift force formula, and a new torque formula. Random arrays of solid particles in fluids are generated with Monte Carlo procedure and Zinchenko's method to avoid crystallization of solid particles over high solid volume fractions. A new drag force formula was developed with extensive simulated results to be closely applicable to real processes over the entire range of packing fractions and both low and moderate particle Reynolds numbers. The simulation results indicate that the drag force is barely affected by rotational Reynolds numbers. Drag force is basically unchanged as the angle of the rotating axis varies.

  2. Gas sampling system for reactive gas-solid mixtures

    DOE Patents [OSTI]

    Daum, Edward D. (Alliance, OH); Downs, William (Alliance, OH); Jankura, Bryan J. (Mogadore, OH); McCoury, Jr., John M. (Mineral City, OH)

    1990-01-01T23:59:59.000Z

    An apparatus and method for sampling gas containing a reactive particulate solid phase flowing through a duct and for communicating a representative sample to a gas analyzer. A sample probe sheath 32 with an angular opening 34 extends vertically into a sample gas duct 30. The angular opening 34 is opposite the gas flow. A gas sampling probe 36 concentrically located within sheath 32 along with calibration probe 40 partly extends in the sheath 32. Calibration probe 40 extends further in the sheath 32 than gas sampling probe 36 for purging the probe sheath area with a calibration gas during calibration.

  3. Gas sampling system for reactive gas-solid mixtures

    DOE Patents [OSTI]

    Daum, Edward D. (Alliance, OH); Downs, William (Alliance, OH); Jankura, Bryan J. (Mogadore, OH); McCoury, Jr., John M. (Mineral City, OH)

    1989-01-01T23:59:59.000Z

    An apparatus and method for sampling a gas containing a reactive particulate solid phase flowing through a duct and for communicating a representative sample to a gas analyzer. A sample probe sheath 32 with an angular opening 34 extends vertically into a sample gas duct 30. The angular opening 34 is opposite the gas flow. A gas sampling probe 36 concentrically located within sheath 32 along with calibration probe 40 partly extend in the sheath 32. Calibration probe 40 extends further in the sheath 32 than gas sampling probe 36 for purging the probe sheath area with a calibration gas during calibration.

  4. Basic research model of natural gas combustion in turbulent flow. Phase 2. Annual report, 1 August 1990-31 July 1991

    SciTech Connect (OSTI)

    Dahm, W.J.A.; Tryggvason, G.; Krasny, R.

    1992-02-17T23:59:59.000Z

    The report describes progress made in extending a local integral method (LIM) model for approximately simulating vorticity transport and mixing, as well as molecular diffusion and reaction of chemical species, in natural gas combustion. The LIM model is fundamentally different from conventional approaches for numerically simulating combustion in turbulent flames, and is based on the experimental observation that the strain-diffusion balance which establishes the mixing and reaction scales in turbulent flames leads to a self-similar internal structure which does not need to be continually re-computed. Instead, these scales are represented by a family of self-similar profile shapes, whose moments are allowed to evolve freely to satisfy the governing equations. The resulting LIM computations thus need only to track the evolution of a material surface in the flow, and solve ODE's (ordinary differential equations) on the surface, rather than PDE's (partial differential equations) throughout the whole flame. The present report describes the application of the LIM model for computing the evolution of conserved scalar fields and the resulting equilibrium reaction processes, and presents results from sample calculations. It also describes the extension of the model to relatively detailed four-step methane-air kinetics together with the thermal nitric oxide mechanism, incorporating asymmetric profiles, and presents results from validation calculations. The application of the LIM approach to the vorticity field is also described.

  5. Sauget Plant Flare Gas Reduction Project

    E-Print Network [OSTI]

    Ratkowski, D. P.

    2007-01-01T23:59:59.000Z

    Empirical analysis of stack gas heating value allowed the Afton Chemical Corporation Sauget Plant to reduce natural gas flow to its process flares by about 50% while maintaining the EPA-required minimum heating value of the gas streams....

  6. Oil and Gas CDT Gas hydrate distribution on tectonically active continental

    E-Print Network [OSTI]

    Henderson, Gideon

    Oil and Gas CDT Gas hydrate distribution on tectonically active continental margins: Impact on gas. Gregory F. Moore, University of Hawaii (USA) http://www.soest.hawaii.edu/moore/ Key Words Gas Hydrates, Faults, Fluid Flow, gas prospectivity Overview Fig. 1. Research on gas hydrates is often undertaken

  7. Test versus predictions for rotordynamic coefficients and leakage rates of hole-pattern gas seals at two clearances in choked and unchoked conditions

    E-Print Network [OSTI]

    Wade, Jonathan Leigh

    2004-09-30T23:59:59.000Z

    and significantly less effective damping. The inlet pressure of the testing ranged from 6.9 bar-a (100 psi-a) to 17.2 bar-a (250 psi-a). He showed that the rotordynamic coefficients are frequency dependent. Holt [7] performed tests on two sets of hole...-pattern seals with different hole depths. The testing was conducted with two different inlet pressures from 6.9 bar-a (100 psi-a) to 17.2 bar-a (250 psi-a). He compared these results to smooth seal test results and also the straight bore honeycomb data from...

  8. 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...

  9. Gas only nozzle

    DOE Patents [OSTI]

    Bechtel, William Theodore (15 Olde Coach Rd., Scotia, NY 12302); Fitts, David Orus (286 Sweetman Rd., Ballston Spa, NY 12020); DeLeonardo, Guy Wayne (60 St. Stephens La., Glenville, NY 12302)

    2002-01-01T23:59:59.000Z

    A diffusion flame nozzle gas tip is provided to convert a dual fuel nozzle to a gas only nozzle. The nozzle tip diverts compressor discharge air from the passage feeding the diffusion nozzle air swirl vanes to a region vacated by removal of the dual fuel components, so that the diverted compressor discharge air can flow to and through effusion holes in the end cap plate of the nozzle tip. In a preferred embodiment, the nozzle gas tip defines a cavity for receiving the compressor discharge air from a peripheral passage of the nozzle for flow through the effusion openings defined in the end cap plate.

  10. Southwest Gas Corporation- Residential Energy Efficiency Rebate Program

    Broader source: Energy.gov [DOE]

    Southwest Gas Corporation (SWG) offers rebates to residential customers in Nevada who purchase energy efficient natural gas tankless water heaters, clothes dryers, windows and smart low-flow...

  11. Gas cleaning system and method

    DOE Patents [OSTI]

    Newby, Richard Allen

    2006-06-06T23:59:59.000Z

    A gas cleaning system for removing at least a portion of contaminants, such as halides, sulfur, particulates, mercury, and others, from a synthesis gas (syngas). The gas cleaning system may include one or more filter vessels coupled in series for removing halides, particulates, and sulfur from the syngas. The gas cleaning system may be operated by receiving gas at a first temperature and pressure and dropping the temperature of the syngas as the gas flows through the system. The gas cleaning system may be used for an application requiring clean syngas, such as, but not limited to, fuel cell power generation, IGCC power generation, and chemical synthesis.

  12. Model documentation: Natural gas transmission and distribution model of the National Energy Modeling System. Volume 1

    SciTech Connect (OSTI)

    NONE

    1995-02-17T23:59:59.000Z

    The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of integrated Analysis and Forecasting of the Energy information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The methodology employed allows the analysis of impacts of regional capacity constraints in the interstate natural gas pipeline network and the identification of pipeline capacity expansion requirements. There is an explicit representation of core and noncore markets for natural gas transmission and distribution services, and the key components of pipeline tariffs are represented in a pricing algorithm. Natural gas pricing and flow patterns are derived by obtaining a market equilibrium across the three main elements of the natural gas market: the supply element, the demand element, and the transmission and distribution network that links them. The NGTDM consists of four modules: the Annual Flow Module, the Capacity F-expansion Module, the Pipeline Tariff Module, and the Distributor Tariff Module. A model abstract is provided in Appendix A.

  13. Supersonic gas compressor

    DOE Patents [OSTI]

    Lawlor, Shawn P. (Bellevue, WA); Novaresi, Mark A. (San Diego, CA); Cornelius, Charles C. (Kirkland, WA)

    2007-11-13T23:59:59.000Z

    A gas compressor based on the use of a driven rotor having a compression ramp traveling at a local supersonic inlet velocity (based on the combination of inlet gas velocity and tangential speed of the ramp) which compresses inlet gas against a stationary sidewall. In using this method to compress inlet gas, the supersonic compressor efficiently achieves high compression ratios while utilizing a compact, stabilized gasdynamic flow path. Operated at supersonic speeds, the inlet stabilizes an oblique/normal shock system in the gasdyanamic flow path formed between the rim of the rotor, the strakes, and a stationary external housing. Part load efficiency is enhanced by the use of a pre-swirl compressor, and using a bypass stream to bleed a portion of the intermediate pressure gas after passing through the pre-swirl compressor back to the inlet of the pre-swirl compressor. Inlet guide vanes to the compression ramp enhance overall efficiency.

  14. Gas-controlled dynamic vacuum insulation with gas gate

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1994-06-07T23:59:59.000Z

    Disclosed is a dynamic vacuum insulation comprising sidewalls enclosing an evacuated chamber and gas control means for releasing hydrogen gas into a chamber to increase gas molecule conduction of heat across the chamber and retrieving hydrogen gas from the chamber. The gas control means includes a metal hydride that absorbs and retains hydrogen gas at cooler temperatures and releases hydrogen gas at hotter temperatures; a hydride heating means for selectively heating the metal hydride to temperatures high enough to release hydrogen gas from the metal hydride; and gate means positioned between the metal hydride and the chamber for selectively allowing hydrogen to flow or not to flow between said metal hydride and said chamber.

  15. Gas-controlled dynamic vacuum insulation with gas gate

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1994-06-07T23:59:59.000Z

    Disclosed is a dynamic vacuum insulation comprising sidewalls enclosing an evacuated chamber and gas control means for releasing hydrogen gas into a chamber to increase gas molecule conduction of heat across the chamber and retrieving hydrogen gas from the chamber. The gas control means includes a metal hydride that absorbs and retains hydrogen gas at cooler temperatures and releases hydrogen gas at hotter temperatures; a hydride heating means for selectively heating the metal hydride to temperatures high enough to release hydrogen gas from the metal hydride; and gate means positioned between the metal hydride and the chamber for selectively allowing hydrogen to flow or not to flow between said metal hydride and said chamber. 25 figs.

  16. Gas cooling performance in disc winding of large-capacity gas-insulated transformer

    SciTech Connect (OSTI)

    Nakadate, M.; Toda, K.; Sato, K.; Biswas, D.; Nakagawa, C.; Yanari, T. [Toshiba Corp., Kawasaki (Japan)] [Toshiba Corp., Kawasaki (Japan)

    1996-04-01T23:59:59.000Z

    The authors have developed the gas-cooling system of a 275 kV, 300 MVA class gas-insulated transformer. In this study model experiments in which gas flow was substituted by water flow equivalently and 2-dimensional numerical flow analyses and network analyses were conducted. In this paper the outline of the development and optimization condition to get high cooling performance in SF{sub 6} gas-disc winding system of the transformer are presented.

  17. Foam patterns

    DOE Patents [OSTI]

    Chaudhry, Anil R; Dzugan, Robert; Harrington, Richard M; Neece, Faurice D; Singh, Nipendra P; Westendorf, Travis

    2013-11-26T23:59:59.000Z

    A method of creating a foam pattern comprises mixing a polyol component and an isocyanate component to form a liquid mixture. The method further comprises placing a temporary core having a shape corresponding to a desired internal feature in a cavity of a mold and inserting the mixture into the cavity of the mold so that the mixture surrounds a portion of the temporary core. The method optionally further comprises using supporting pins made of foam to support the core in the mold cavity, with such pins becoming integral part of the pattern material simplifying subsequent processing. The method further comprises waiting for a predetermined time sufficient for a reaction from the mixture to form a foam pattern structure corresponding to the cavity of the mold, wherein the foam pattern structure encloses a portion of the temporary core and removing the temporary core from the pattern independent of chemical leaching.

  18. Production Trends of Shale Gas Wells

    E-Print Network [OSTI]

    Khan, Waqar A.

    2010-01-14T23:59:59.000Z

    To obtain better well performance and improved production from shale gas reservoirs, it is important to understand the behavior of shale gas wells and to identify different flow regions in them over a period of time. It is also important...

  19. Mobile Monolith Polymer Elements For Flow Control In Microfluidic Systems

    DOE Patents [OSTI]

    Hasselbrink, Jr., Ernest F. (Saline, MI); Rehm, Jason E. (Alameda, CA); Shepodd, Timothy J. (Livermore, CA); Kirby, Brian J. (San Francisco, CA)

    2006-01-24T23:59:59.000Z

    A cast-in-place and lithographically shaped mobile, monolithic polymer element for fluid flow control in microfluidic devices and method of manufacture. Microfluid flow control devices, or microvalves that provide for control of fluid or ionic current flow can be made incorporating a cast-in-place, mobile monolithic polymer element, disposed within a microchannel, and driven by fluid pressure (either liquid or gas) against a retaining or sealing surface. The polymer elements are made by the application of lithographic methods to monomer mixtures formulated in such a way that the polymer will not bond to microchannel walls. The polymer elements can seal against pressures greater than 5000 psi, and have a response time on the order of milliseconds. By the use of energetic radiation it is possible to depolymerize selected regions of the polymer element to form shapes that cannot be produced by conventional lithographic patterning and would be impossible to machine.

  20. Journal of Chromatography A, 1086 (2005) 165170 Peak pattern variations related to comprehensive two-dimensional

    E-Print Network [OSTI]

    Reichenbach, Stephen E.

    2005-01-01T23:59:59.000Z

    non-linear pattern variations and changes in gas pressure generate nearly linear pattern variations Abstract Identifying compounds of interest for peaks in data generated by comprehensive two-dimensional gas and inlet gas pressure and evaluates two types of affine transformations for matching peak patterns

  1. Automated gas chromatography

    DOE Patents [OSTI]

    Mowry, Curtis D. (Albuquerque, NM); Blair, Dianna S. (Albuquerque, NM); Rodacy, Philip J. (Albuquerque, NM); Reber, Stephen D. (Corrales, NM)

    1999-01-01T23:59:59.000Z

    An apparatus and process for the continuous, near real-time monitoring of low-level concentrations of organic compounds in a liquid, and, more particularly, a water stream. A small liquid volume of flow from a liquid process stream containing organic compounds is diverted by an automated process to a heated vaporization capillary where the liquid volume is vaporized to a gas that flows to an automated gas chromatograph separation column to chromatographically separate the organic compounds. Organic compounds are detected and the information transmitted to a control system for use in process control. Concentrations of organic compounds less than one part per million are detected in less than one minute.

  2. Two-component Bose gas trapped by harmonic and annular potentials: Supercurrent, vortex flow and instability of superfluidity by Rabi coupling

    E-Print Network [OSTI]

    Ino, Hayato; Ichinose, Ikuo

    2015-01-01T23:59:59.000Z

    In this paper, we study a system of two-component Bose gas in an artificial magnetic field trapped by concentric harmonic and annular potentials, respectively. The system is realized by gases with two-internal states like the hyperfine states of $^{87}$Rb. We are interested in effects of a Rabi oscillation between them. Two-component Bose Hubbard model is introduced to describe the system, and Gross-Pitaevskii equations are used to study the system. We first study the Bose gas system in the annular trap by varying the width of the annulus and strength of the magnetic field, in particular, we focus on the phase slip and superflow. Then we consider the coupled Bose gas system in a magnetic field. In a strong magnetic field, vortices form a Abrikosov triangular lattice in both Bose-Einstein condensates (BECs), and locations of vortices in the BECs correlate with each other by the Rabi coupling. However, as the strength of the Rabi coupling is increased, vortices start to vibrate around their equilibrium location...

  3. Multiphase Flow and Cavern Abandonment in Salt

    SciTech Connect (OSTI)

    Ehgartner, Brian; Tidwell, Vince

    2001-02-13T23:59:59.000Z

    This report will explore the hypothesis that an underground cavity in gassy salt will eventually be gas filled as is observed on a small scale in some naturally occurring salt inclusions. First, a summary is presented on what is known about gas occurrences, flow mechanisms, and cavern behavior after abandonment. Then, background information is synthesized into theory on how gas can fill a cavern and simultaneously displace cavern fluids into the surrounding salt. Lastly, two-phase (gas and brine) flow visualization experiments are presented that demonstrate some of the associated flow mechanisms and support the theory and hypothesis that a cavity in salt can become gas filled after plugging and abandonment

  4. Exhaust gas recirculation apparatus

    SciTech Connect (OSTI)

    Egnell, R.A.; Hansson, B.L.

    1981-07-14T23:59:59.000Z

    Apparatus is disclosed for recirculating combustion exhaust gases to the burner region of a Stirling cycle hot-gas engine to lower combustion temperature and reduct NO/sub x/ formation includes a first wall separating the exhaust gas stream from the inlet air stream, a second wall separating the exhaust gas stream from the burner region, and low flow resistance ejectors formed in the first and second walls for admitting the inlet air to the burner region and for entraining and mixing with the inlet air portion of the exhaust gas stream. In a preferred embodiment the ejectors are arranged around the periphery of a cylindrical burner region and oriented to admit the air/exhaust gas mixture tangentially to promote mixing. In another preferred embodiment a single annular ejector surrounds and feeds the air/exhaust gas mixture to a cylindrical burner region. The annular ejector includes an annular plate with radially-directed flow passages to provide an even distribution of the air/exhaust gas mixture to the burner region.

  5. Submarine pingoes: Indicators of shallow gas hydrates in a pockmark at Nyegga, Norwegian Sea

    E-Print Network [OSTI]

    Svensen, Henrik

    Submarine pingoes: Indicators of shallow gas hydrates in a pockmark at Nyegga, Norwegian Sea Martin; Nyegga; gas hydrates; fluid flow; sediment stability; shallow gas; methane flow; porewater flow 1. Introduction It has long been known that gas hydrates hosted in oceanic low-permeable sediments have

  6. Numerical Modeling of Fractured Shale-Gas and Tight-Gas Reservoirs Using Unstructured Grids

    E-Print Network [OSTI]

    Olorode, Olufemi Morounfopefoluwa

    2012-02-14T23:59:59.000Z

    Various models featuring horizontal wells with multiple induced fractures have been proposed to characterize flow behavior over time in tight gas and shale gas systems. Currently, there is little consensus regarding the effects of non...

  7. Sandia National Laboratories: investigate flow patterns before...

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

    and minimize environmental effects. The CEC array optimization framework was applied to Cobscook Bay, Maine, the first deployment site of the Ocean Renewable Power Company's...

  8. Single chamber fuel cells: Flow geometry, rate and composition considerations

    SciTech Connect (OSTI)

    Stefan, Ionel C.; Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2003-11-17T23:59:59.000Z

    Four different single chamber fuel cell designs were compared using propane-air gas mixtures. Gas flow around the electrodes has a significant influence on the open circuit voltage and the power density of the cell. The strong influence of flow geometry is likely due to its effect on gas composition, particularly on the oxygen chemical potential at the two electrodes as a result of gas mixing. The chamber design which exposes the cathode first to the inlet gas was found to yield the best performance at lower flow rates, while the open tube design with the electrodes equally exposed to the inlet gas worked best at higher flow rates.

  9. Novel selective surface flow (SSF{trademark}) membranes for the recovery of hydrogen from waste gas streams. Phase 2: Technology development, final report

    SciTech Connect (OSTI)

    Anand, M.; Ludwig, K.A.

    1996-04-01T23:59:59.000Z

    The objective of Phase II of the Selective Surface Flow Membrane program was Technology Development. Issues addressed were: (i) to develop detailed performance characteristics on a 1 ft{sup 2} multi- tube module and develop design data, (ii) to build a field test rig and complete field evaluation with the 1 ft{sup 2} area membrane system, (iii) to implement membrane preparation technology and demonstrate membrane performance in 3.5 ft long tube, (iv) to complete detailed process design and economic analysis.

  10. Gas only nozzle fuel tip

    DOE Patents [OSTI]

    Bechtel, William Theodore (Scotia, NY); Fitts, David Orus (Ballston Spa, NY); DeLeonardo, Guy Wayne (Glenville, NY)

    2002-01-01T23:59:59.000Z

    A diffusion flame nozzle gas tip is provided to convert a dual fuel nozzle to a gas only nozzle. The nozzle tip diverts compressor discharge air from the passage feeding the diffusion nozzle air swirl vanes to a region vacated by removal of the dual fuel components, so that the diverted compressor discharge air can flow to and through effusion holes in the end cap plate of the nozzle tip. In a preferred embodiment, the nozzle gas tip defines a cavity for receiving the compressor discharge air from a peripheral passage of the nozzle for flow through the effusion openings defined in the end cap plate.

  11. The transition from the annular to the slug flow regime in two-phase flow

    E-Print Network [OSTI]

    Haberstroh, Robert D.

    1964-01-01T23:59:59.000Z

    Experiments were conducted to determine the transition from annular to semiannular flow regimes for two-phase, gas-liquid upflow in vertical tubes. The influencesof liquid flow rate, tube diameter, liquid viscosity, surface ...

  12. 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 ...

  13. Convective cores in galactic cooling flows

    E-Print Network [OSTI]

    A. Kritsuk; T. Plewa; E. Mueller

    2001-05-02T23:59:59.000Z

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

  14. High Temperature Gas Reactors The Next Generation ?

    E-Print Network [OSTI]

    -Proof Advanced Reactor and Gas Turbine #12;Flow through Power Conversion Vessel 8 #12;9 TRISO Fuel Particle1 High Temperature Gas Reactors The Next Generation ? Professor Andrew C Kadak Massachusetts of Brayton vs. Rankine Cycle · High Temperature Helium Gas (900 C) · Direct or Indirect Cycle · Originally

  15. Photoacoustic infrared spectroscopy for conducting gas tracer tests and measuring water saturations in landfills

    SciTech Connect (OSTI)

    Jung, Yoojin; Han, Byunghyun; Mostafid, M. Erfan; Chiu, Pei [Department of Civil and Environmental Engineering, University of Delaware, Newark, DE 19716 (United States); Yazdani, Ramin [Yolo County Planning and Public Works Department, Division of Integrated Waste Management, Yolo County, 44090 County Rd. 28H, Woodland, CA 95776 (United States); Imhoff, Paul T., E-mail: imhoff@udel.edu [Department of Civil and Environmental Engineering, University of Delaware, Newark, DE 19716 (United States)

    2012-02-15T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer Photoacoustic infrared spectroscopy tested for measuring tracer gas in landfills. Black-Right-Pointing-Pointer Measurement errors for tracer gases were 1-3% in landfill gas. Black-Right-Pointing-Pointer Background signals from landfill gas result in elevated limits of detection. Black-Right-Pointing-Pointer Technique is much less expensive and easier to use than GC. - Abstract: Gas tracer tests can be used to determine gas flow patterns within landfills, quantify volatile contaminant residence time, and measure water within refuse. While gas chromatography (GC) has been traditionally used to analyze gas tracers in refuse, photoacoustic spectroscopy (PAS) might allow real-time measurements with reduced personnel costs and greater mobility and ease of use. Laboratory and field experiments were conducted to evaluate the efficacy of PAS for conducting gas tracer tests in landfills. Two tracer gases, difluoromethane (DFM) and sulfur hexafluoride (SF{sub 6}), were measured with a commercial PAS instrument. Relative measurement errors were invariant with tracer concentration but influenced by background gas: errors were 1-3% in landfill gas but 4-5% in air. Two partitioning gas tracer tests were conducted in an aerobic landfill, and limits of detection (LODs) were 3-4 times larger for DFM with PAS versus GC due to temporal changes in background signals. While higher LODs can be compensated by injecting larger tracer mass, changes in background signals increased the uncertainty in measured water saturations by up to 25% over comparable GC methods. PAS has distinct advantages over GC with respect to personnel costs and ease of use, although for field applications GC analyses of select samples are recommended to quantify instrument interferences.

  16. Simulating the Effect of Water on the Fracture System of Shale Gas Wells 

    E-Print Network [OSTI]

    Hamam, Hassan Hasan H.

    2011-10-21T23:59:59.000Z

    It was observed that many hydraulically fractured horizontal shale gas wells exhibit transient linear flow behavior. A half-slope on a type curve represents this transient linear flow behavior. Shale gas wells show a significant skin effect which...

  17. Deliverability on the interstate natural gas pipeline system

    SciTech Connect (OSTI)

    NONE

    1998-05-01T23:59:59.000Z

    Deliverability on the Interstate Natural Gas Pipeline System examines the capability of the national pipeline grid to transport natural gas to various US markets. The report quantifies the capacity levels and utilization rates of major interstate pipeline companies in 1996 and the changes since 1990, as well as changes in markets and end-use consumption patterns. It also discusses the effects of proposed capacity expansions on capacity levels. The report consists of five chapters, several appendices, and a glossary. Chapter 1 discusses some of the operational and regulatory features of the US interstate pipeline system and how they affect overall system design, system utilization, and capacity expansions. Chapter 2 looks at how the exploration, development, and production of natural gas within North America is linked to the national pipeline grid. Chapter 3 examines the capability of the interstate natural gas pipeline network to link production areas to market areas, on the basis of capacity and usage levels along 10 corridors. The chapter also examines capacity expansions that have occurred since 1990 along each corridor and the potential impact of proposed new capacity. Chapter 4 discusses the last step in the transportation chain, that is, deliverability to the ultimate end user. Flow patterns into and out of each market region are discussed, as well as the movement of natural gas between States in each region. Chapter 5 examines how shippers reserve interstate pipeline capacity in the current transportation marketplace and how pipeline companies are handling the secondary market for short-term unused capacity. Four appendices provide supporting data and additional detail on the methodology used to estimate capacity. 32 figs., 15 tabs.

  18. Gas turbine combustor transition

    DOE Patents [OSTI]

    Coslow, Billy Joe (Winter Park, FL); Whidden, Graydon Lane (Great Blue, CT)

    1999-01-01T23:59:59.000Z

    A method of converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit.

  19. Gas turbine combustor transition

    DOE Patents [OSTI]

    Coslow, B.J.; Whidden, G.L.

    1999-05-25T23:59:59.000Z

    A method is described for converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit. 7 figs.

  20. Sensitivity of Fischer-Tropsch Synthesis and Water-Gas Shift Catalysts to Poisons from High-Temperature High-Pressure Entrained-Flow (EF) Oxygen-Blown Gasifier Gasification of Coal/Biomass Mixtures

    SciTech Connect (OSTI)

    Burton Davis; Gary Jacobs; Wenping Ma; Dennis Sparks; Khalid Azzam; Janet Chakkamadathil Mohandas; Wilson Shafer; Venkat Ramana Rao Pendyala

    2011-09-30T23:59:59.000Z

    There has been a recent shift in interest in converting not only natural gas and coal derived syngas to Fischer-Tropsch synthesis products, but also converting biomass-derived syngas, as well as syngas derived from coal and biomass mixtures. As such, conventional catalysts based on iron and cobalt may not be suitable without proper development. This is because, while ash, sulfur compounds, traces of metals, halide compounds, and nitrogen-containing chemicals will likely be lower in concentration in syngas derived from mixtures of coal and biomass (i.e., using entrained-flow oxygen-blown gasifier gasification gasification) than solely from coal, other compounds may actually be increased. Of particular concern are compounds containing alkali chemicals like the chlorides of sodium and potassium. In the first year, University of Kentucky Center for Applied Energy Research (UK-CAER) researchers completed a number of tasks aimed at evaluating the sensitivity of cobalt and iron-based Fischer-Tropsch synthesis (FT) catalysts and a commercial iron-chromia high temperature water-gas shift catalyst (WGS) to alkali halides. This included the preparation of large batches of 0.5%Pt-25%Co/Al{sub 2}O{sub 3} and 100Fe: 5.1Si: 3.0K: 2.0Cu (high alpha) catalysts that were split up among the four different entities participating in the overall project; the testing of the catalysts under clean FT and WGS conditions; the testing of the Fe-Cr WGS catalyst under conditions of co-feeding NaCl and KCl; and the construction and start-up of the continuously stirred tank reactors (CSTRs) for poisoning investigations. In the second and third years, researchers from the University of Kentucky Center for Applied Energy Research (UK-CAER) continued the project by evaluating the sensitivity of a commercial iron-chromia high temperature water-gas shift catalyst (WGS) to a number of different compounds, including KHCO{sub 3}, NaHCO{sub 3}, HCl, HBr, HF, H{sub 2}S, NH{sub 3}, and a combination of H{sub 2}S and NH{sub 3}. Cobalt and iron-based Fischer-Tropsch synthesis (FT) catalysts were also subjected to a number of the same compounds in order to evaluate their sensitivities at different concentration levels of added contaminant.

  1. Method and apparatus for dispensing compressed natural gas and liquified natural gas to natural gas powered vehicles

    DOE Patents [OSTI]

    Bingham, Dennis A.; Clark, Michael L.; Wilding, Bruce M.; Palmer, Gary L.

    2005-05-31T23:59:59.000Z

    A fueling facility and method for dispensing liquid natural gas (LNG), compressed natural gas (CNG) or both on-demand. The fueling facility may include a source of LNG, such as cryogenic storage vessel. A low volume high pressure pump is coupled to the source of LNG to produce a stream of pressurized LNG. The stream of pressurized LNG may be selectively directed through an LNG flow path or to a CNG flow path which includes a vaporizer configured to produce CNG from the pressurized LNG. A portion of the CNG may be drawn from the CNG flow path and introduced into the CNG flow path to control the temperature of LNG flowing therethrough. Similarly, a portion of the LNG may be drawn from the LNG flow path and introduced into the CNG flow path to control the temperature of CNG flowing therethrough.

  2. Gas-cooled nuclear reactor

    DOE Patents [OSTI]

    Peinado, Charles O. (La Jolla, CA); Koutz, Stanley L. (San Diego, CA)

    1985-01-01T23:59:59.000Z

    A gas-cooled nuclear reactor includes a central core located in the lower portion of a prestressed concrete reactor vessel. Primary coolant gas flows upward through the core and into four overlying heat-exchangers wherein stream is generated. During normal operation, the return flow of coolant is between the core and the vessel sidewall to a pair of motor-driven circulators located at about the bottom of the concrete pressure vessel. The circulators repressurize the gas coolant and return it back to the core through passageways in the underlying core structure. If during emergency conditions the primary circulators are no longer functioning, the decay heat is effectively removed from the core by means of natural convection circulation. The hot gas rising through the core exits the top of the shroud of the heat-exchangers and flows radially outward to the sidewall of the concrete pressure vessel. A metal liner covers the entire inside concrete surfaces of the concrete pressure vessel, and cooling tubes are welded to the exterior or concrete side of the metal liner. The gas coolant is in direct contact with the interior surface of the metal liner and transfers its heat through the metal liner to the liquid coolant flowing through the cooling tubes. The cooler gas is more dense and creates a downward convection flow in the region between the core and the sidewall until it reaches the bottom of the concrete pressure vessel when it flows radially inward and up into the core for another pass. Water is forced to flow through the cooling tubes to absorb heat from the core at a sufficient rate to remove enough of the decay heat created in the core to prevent overheating of the core or the vessel.

  3. 8 TH INTERNATIONAL SYMPOSIUM ON FLOW VISUALIZATION (1998) V I SUALISAT I ON OF FLOW PHENOMENA I NSIDE

    E-Print Network [OSTI]

    of a reactor vessel containing a fixed­bed of solids via a gas distributor. The upward flow of gas causes­solid flow, circulating fluidized bed, cluster Abstract In the present paper an attempt has been made to use the laser sheet method inside a circulating fluidized bed (CFB) which is a highly concentrated gas

  4. Preparation of a heteroepitaxial La{sub x}Sr{sub y}Mn{sub z}O{sub 3}/BiFeO{sub 3} bilayer by r.f. magnetron sputtering with various oxygen gas flow ratios

    SciTech Connect (OSTI)

    Naganuma, H., E-mail: naganuma@mlab.apph.tohoku.ac.jp; Ichinose, T.; Begum, H. A.; Sato, S.; Oogane, M.; Ando, Y. [Department of Applied Physics, Graduate School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Han, X. F. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Miyazaki, T. [Group of Communication Engineering, Graduate School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Bae, In-T. [Small Scale Systems Integration and Packaging Center, State University of New York at Binghamton, Binghamton, NY 13902 (United States)

    2014-08-15T23:59:59.000Z

    BiFeO{sub 3} (BFO) and La{sub x}Sr{sub y}Mn{sub z}O{sub 3} (LSMO) films were epitaxially grown on SrTiO{sub 3} (100) substrates by r.f. magnetron sputtering with various oxygen gas flow ratios (F{sub O2}). Compositional ratios of each atom in both of BFO and LSMO could be controlled kept to around 10 at.% by changing F{sub O2}. Adjusting the compositional ratio to La{sub 0.35}Sr{sub 0.15}Mn{sub 0.5}O{sub 3} not only increase T{sub c} of LSMO but also produces sufficient oxygen to form a perovskite lattice. For an LSMO/BFO heterostructure, detailed observation by cross sectional transmission electron microscopy (TEM) revealed that the lattice of rhombohedral (SG: R-3c) LSMO was shrank by a clamping effect from the SrTiO{sub 3} substrates, and then the BFO was grown in two layers: (i) an interfacial BFO layer (7 nm thick) with evenly shrunk a-axis and c-axis, and (ii) an upper BFO layer (25 nm thick) expanded along the c-axis. Neither misfit strain nor dislocations appeared at the interface between the shrunken BFO and LSMO layers, and these heterostructures did not show exchange bias. These results suggest that BFO is suitable for a tunneling barrier combine with LSMO electrode.

  5. System for measuring multiphase flow using multiple pressure differentials

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2003-01-01T23:59:59.000Z

    An improved method and system for measuring a multi-phase flow in a pressure flow meter. An extended throat venturi is used and pressure of the multi-phase flow is measured at three or more positions in the venturi, which define two or more pressure differentials in the flow conduit. The differential pressures are then used to calculate the mass flow of the gas phase, the total mass flow, and the liquid phase. The system for determining the mass flow of the high void fraction fluid flow and the gas flow includes taking into account a pressure drop experienced by the gas phase due to work performed by the gas phase in accelerating the liquid phase.

  6. Automated gas chromatography

    DOE Patents [OSTI]

    Mowry, C.D.; Blair, D.S.; Rodacy, P.J.; Reber, S.D.

    1999-07-13T23:59:59.000Z

    An apparatus and process for the continuous, near real-time monitoring of low-level concentrations of organic compounds in a liquid, and, more particularly, a water stream. A small liquid volume of flow from a liquid process stream containing organic compounds is diverted by an automated process to a heated vaporization capillary where the liquid volume is vaporized to a gas that flows to an automated gas chromatograph separation column to chromatographically separate the organic compounds. Organic compounds are detected and the information transmitted to a control system for use in process control. Concentrations of organic compounds less than one part per million are detected in less than one minute. 7 figs.

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

    DOE Patents [OSTI]

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

    2013-09-10T23:59:59.000Z

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

  8. Optimization for Design and Operation of Natural Gas Transmission Networks

    E-Print Network [OSTI]

    Dilaveroglu, Sebnem 1986-

    2012-08-22T23:59:59.000Z

    and compressor stations. On an existing network, the model also optimizes the total flow through pipelines that satisfy demand to determine the best purchase amount of gas. A mixed integer nonlinear programming model for steady-state natural gas transmission...

  9. Method of Liquifying a gas

    DOE Patents [OSTI]

    Zollinger, William T.; Bingham, Dennis N.; McKellar, Michael G.; Wilding, Bruce M.; Klingler, Kerry M.

    2006-02-14T23:59:59.000Z

    A method of liquefying a gas is disclosed and which includes the steps of pressurizing a liquid; mixing a reactant composition with the pressurized liquid to generate a high pressure gas; supplying the high pressure gas to an expansion engine which produces a gas having a reduced pressure and temperature, and which further generates a power and/or work output; coupling the expansion engine in fluid flowing relation relative to a refrigeration assembly, and wherein the gas having the reduced temperature is provided to the refrigeration assembly; and energizing and/or actuating the refrigeration assembly, at least in part, by supplying the power and/or work output generated by the expansion engine to the refrigeration assembly, the refrigeration assembly further reducing the temperature of the gas to liquefy same.

  10. Pattern speed evolution and bar reformation

    E-Print Network [OSTI]

    F. Combes

    2008-11-05T23:59:59.000Z

    Bars in spiral galaxies can weaken through gas inflow towards the center, and angular momentum transfer. Several bar episodes can follow one another in the life of the galaxy, if sufficient gas is accreted from the intergalactic medium to revive young disks. Pattern speeds of the successive bars are different, due to mass concentration, or increased velocity dispersion of the remaining stellar component. In the same time, the spiral galaxy evolves in morphological type. Numerical simulations are presented, trying to correlate type and bar pattern speeds.

  11. Experimental Investigation on High-pressure, High-temperature Viscosity of Gas Mixtures

    E-Print Network [OSTI]

    Davani, Ehsan

    2012-02-14T23:59:59.000Z

    Modeling the performance of high-pressure, high-temperature (HPHT) natural gas reservoirs requires the understanding of gas behavior at such conditions. In particular, gas viscosity is an important fluid property that directly affects fluid flow...

  12. International Conference on Gas Hydrates May 19-23, 2002, Yokohama

    E-Print Network [OSTI]

    Gudmundsson, Jon Steinar

    4th International Conference on Gas Hydrates May 19-23, 2002, Yokohama Cold Flow Hydrate Technology an opportunity for flow assurance in deepwater production of oil and gas. Hydrate R&D in the Natural Gas Hydrate exchange and reactor units. Introduction Hydrates form when liquid water and natural gas are in contact

  13. advanced hot gas: Topics by E-print Network

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

    Recent ROSAT observations indicate gas temperatures in excess of the virial stellar temperature, totally unlike standard cooling flow models. However, these new results can be...

  14. Experimental Investigation of Propped Fracture Conductivity in Tight Gas Reservoirs Using The Dynamic Conductivity Test

    E-Print Network [OSTI]

    Romero Lugo, Jose 1985-

    2012-10-24T23:59:59.000Z

    deep into the formation, changing the flow pattern from radial to linear flow. The dynamic conductivity test was used for this research to evaluate the effect of closure stress, temperature, proppant concentration, and flow back rates on fracture...

  15. Gas cooled traction drive inverter

    DOE Patents [OSTI]

    Chinthavali, Madhu Sudhan

    2013-10-08T23:59:59.000Z

    The present invention provides a modular circuit card configuration for distributing heat among a plurality of circuit cards. Each circuit card includes a housing adapted to dissipate heat in response to gas flow over the housing. In one aspect, a gas-cooled inverter includes a plurality of inverter circuit cards, and a plurality of circuit card housings, each of which encloses one of the plurality of inverter cards.

  16. Can We Accurately Model Fluid Flow in Shale?

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

    2013 00:00 Over 20 trillion cubic meters of natural gas are trapped in shale, but many shale oil and gas producers still use models of underground fluid flow that date back to...

  17. A front-tracking method for the simulation of three-phase flow in porous media

    E-Print Network [OSTI]

    , the simultaneous flow of oil, water, and gas in the reservoir. Practical examples include primary production below bubble point and with movable water, waterfloods in the presence of free gas, gas floods, and water

  18. Heat Flow, Heat Transfer And Lithosphere Rheology In Geothermal...

    Open Energy Info (EERE)

    heat flow values as high as several watts per meter squared can be found. Systematic interpretation of heat flow patterns sheds light on heat transfer mechanisms at depth on...

  19. Flow characteristics in underground coal gasification

    SciTech Connect (OSTI)

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

    1982-01-01T23:59:59.000Z

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

  20. Response of a slotted plate flow meter to horizontal two phase flow

    E-Print Network [OSTI]

    Muralidharan, Vasanth

    2005-02-17T23:59:59.000Z

    there is a change in the pipeline geometry or 8 inclination. Severe riser slugging is an example of this effect and it can prevail for kilometers mainly in sea lines. When there are no transient effects or geometry/terrain effects the flow is steady... constant, a static differential pressure due to flow of the pure liquid is attained. 9 Therefore the static differential pressure lines of constant liquid flow rate become horizontal when the gas flow rate is reduced. 4. When the gas flow is increased...

  1. Cross-flow electrochemical reactor cells, cross-flow reactors, and use of cross-flow reactors for oxidation reactions

    DOE Patents [OSTI]

    Balachandran, Uthamalingam (Hinsdale, IL); Poeppel, Roger B. (Glen Ellyn, IL); Kleefisch, Mark S. (Naperville, IL); Kobylinski, Thaddeus P. (Lisle, IL); Udovich, Carl A. (Joliet, IL)

    1994-01-01T23:59:59.000Z

    This invention discloses cross-flow electrochemical reactor cells containing oxygen permeable materials which have both electron conductivity and oxygen ion conductivity, cross-flow reactors, and electrochemical processes using cross-flow reactor cells having oxygen permeable monolithic cores to control and facilitate transport of oxygen from an oxygen-containing gas stream to oxidation reactions of organic compounds in another gas stream. These cross-flow electrochemical reactors comprise a hollow ceramic blade positioned across a gas stream flow or a stack of crossed hollow ceramic blades containing a channel or channels for flow of gas streams. Each channel has at least one channel wall disposed between a channel and a portion of an outer surface of the ceramic blade, or a common wall with adjacent blades in a stack comprising a gas-impervious mixed metal oxide material of a perovskite structure having electron conductivity and oxygen ion conductivity. The invention includes reactors comprising first and second zones seprated by gas-impervious mixed metal oxide material material having electron conductivity and oxygen ion conductivity. Prefered gas-impervious materials comprise at least one mixed metal oxide having a perovskite structure or perovskite-like structure. The invention includes, also, oxidation processes controlled by using these electrochemical reactors, and these reactions do not require an external source of electrical potential or any external electric circuit for oxidation to proceed.

  2. Gas condensate damage in hydraulically fractured wells

    E-Print Network [OSTI]

    Adeyeye, Adedeji Ayoola

    2004-09-30T23:59:59.000Z

    Company. The well was producing a gas condensate reservoir and questions were raised about how much drop in flowing bottomhole pressure below dewpoint would be appropriate. Condensate damage in the hydraulic fracture was expected to be of significant...

  3. Affording Gas and Electricity: Self Disconnection and

    E-Print Network [OSTI]

    Feigon, Brooke

    Affording Gas and Electricity: Self Disconnection and Rationing by Prepayment and Low Income Credit interview schedule................................... liv #12;2 Fuel Usage and Consumption Patterns of Low electricity, but this seems to be because gas prepayers have lower average income than electricity prepayers

  4. Pipeline Politics: Natural Gas in Eurasia

    E-Print Network [OSTI]

    Landrum, William W.; Llewellyn, Benjamin B.; Limesand, Craig M.; Miller, Dante J.; Morris, James P.; Nowell, Kathleen S.; Sherman, Charlotte L.

    2010-01-01T23:59:59.000Z

    Eurasia is a major source of oil and natural gas, and events in the region have a great potential to destabilize global security patterns. Supplies of natural gas and oil from Eurasia are vital for the functioning of European economies, and also...

  5. Design and Fabrication of a Vertical Pump Multiphase Flow Loop

    E-Print Network [OSTI]

    Kirkland, Klayton 1965-

    2012-08-24T23:59:59.000Z

    is supplied by separate air and water inlet flows that mix just before entering the pump. These flows can be controlled to give a desired gas volume fraction and overall flow rate. The pump outlet flows into a tank which separates the fluids allowing them...

  6. Passive gas separator and accumulator device

    DOE Patents [OSTI]

    Choe, H.; Fallas, T.T.

    1994-08-02T23:59:59.000Z

    A separation device employing a gas separation filter and swirler vanes for separating gas from a gas-liquid mixture is provided. The cylindrical filter utilizes the principle that surface tension in the pores of the filter prevents gas bubbles from passing through. As a result, the gas collects in the interior region of the filter and coalesces to form larger bubbles in the center of the device. The device is particularly suited for use in microgravity conditions since the swirlers induce a centrifugal force which causes liquid to move from the inner region of the filter, pass the pores, and flow through the outlet of the device while the entrained gas is trapped by the filter. The device includes a cylindrical gas storage screen which is enclosed by the cylindrical gas separation filter. The screen has pores that are larger than those of the filters. The screen prevents larger bubbles that have been formed from reaching and interfering with the pores of the gas separation filter. The device is initially filled with a gas other than that which is to be separated. This technique results in separation of the gas even before gas bubbles are present in the mixture. Initially filling the device with the dissimilar gas and preventing the gas from escaping before operation can be accomplished by sealing the dissimilar gas in the inner region of the separation device with a ruptured disc which can be ruptured when the device is activated for use. 3 figs.

  7. Flow characteristics in underground coal gasification

    SciTech Connect (OSTI)

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

    1982-01-01T23:59:59.000Z

    During the underground coal gasification field test at the Hoe Creek site No. 2, Wyoming, helium pulses were introduced to develop information to characterize the flow field, and to estimate the coefficients in dispersion models of the flow. Quantitative analysis of the tracer response curves shows an increasing departure from a plug flow regime with time because of the combined effects of the free and forced convection in addition to the complex non-uniformity of the flow field. The Peclet number was a function of temperature, pressure, gas recovery and characteristic velocity, as well as the split of the gas between the parallel streams in the model. 17 refs.

  8. Natural gas 1995: Issues and trends

    SciTech Connect (OSTI)

    NONE

    1995-11-01T23:59:59.000Z

    Natural Gas 1995: Issues and Trends addresses current issues affecting the natural gas industry and markets. Highlights of recent trends include: Natural gas wellhead prices generally declined throughout 1994 and for 1995 averages 22% below the year-earlier level; Seasonal patterns of natural gas production and wellhead prices have been significantly reduced during the past three year; Natural gas production rose 15% from 1985 through 1994, reaching 18.8 trillion cubic feet; Increasing amounts of natural gas have been imported; Since 1985, lower costs of producing and transporting natural gas have benefitted consumers; Consumers may see additional benefits as States examine regulatory changes aimed at increasing efficiency; and, The electric industry is being restructured in a fashion similar to the recent restructuring of the natural gas industry.

  9. 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.

  10. Gas custody measurement accuracy improved in Saudi Arabia

    SciTech Connect (OSTI)

    Ali, I. (Saudi Arabian Oil Co., Dhahran (Saudi Arabia))

    1994-06-06T23:59:59.000Z

    To comply with new and more accurate gas measurement standards, Saudi Arabian Oil Co. (Saudi Aramco) modified software for existing flow computers and installed an on-line gas chromatograph for measuring natural gas and ethane-rich gas sales. For gases of varying composition (e.g., ethane-rich gas), a knowledge of the pressure, volume, and temperature (PVT) relationship is required for determining supercompressibility factors. The BWR-Starling equation of state was determined to best represent ethane-rich gas properties and is programmed in the new flow computers. The paper discusses gas sales, previous installations, previous calculations, revised calculations, application to ethane-rich gas, the orifice-flow constant, and field modifications of computers.

  11. Gas condensate damage in hydraulically fractured wells

    E-Print Network [OSTI]

    Reza, Rostami Ravari

    2004-11-15T23:59:59.000Z

    of this research are a step forward in helping to improve the management of gas condensate reservoirs by understanding the mechanics of liquid build-up. It also provides methodology for quantifying the condensate damage that impairs linear flow of gas...

  12. REVISED NATURAL GAS MARKET ASSESSMENT

    E-Print Network [OSTI]

    natural gas (LNG) imports into North America increase up to 14 billion cubic feet per day by 2017. Regasified LNG imports from Mexico into San Diego begin in 2009. This LNG displaces domestic production from pipeline reverses and expands to allow the flow of regasified LNG from the Costa Azul LNG terminal in Baja

  13. Multiphase flow in fractured porous media

    SciTech Connect (OSTI)

    Firoozabadi, A.

    1995-02-01T23:59:59.000Z

    The major goal of this research project was to improve the understanding of the gas-oil two-phase flow in fractured porous media. In addition, miscible displacement was studied to evaluate its promise for enhanced recovery.

  14. Gas-Surface Energy Exchange in Collisions of Helium Atoms with Aligned Single-Walled Carbon

    E-Print Network [OSTI]

    Maruyama, Shigeo

    1 Gas-Surface Energy Exchange in Collisions of Helium Atoms with Aligned Single-Walled Carbon #12;2 ABSTRACT Since gas flows in micro/nano devices are dominated by the interaction of gas molecules accommodation of gas molecules on surfaces. The scattering of gas molecules on quartz surfaces covered with VA

  15. Understanding the evolution of miscible viscous fingering patterns

    E-Print Network [OSTI]

    Chui, Jane (Jane Yuen Yung)

    2012-01-01T23:59:59.000Z

    Viscous fingering, the hydrodynamic instability that occurs when a lower viscosity fluid displaces a higher viscosity fluid, creates complex patterns in porous media flows. Fundamental facets of the displacement process, ...

  16. Passive gas separator and accumulator device

    DOE Patents [OSTI]

    Choe, Hwang (Saratoga, CA); Fallas, Thomas T. (Berkeley, CA)

    1994-01-01T23:59:59.000Z

    A separation device employing a gas separation filter and swirler vanes for separating gas from a gasliquid mixture is provided. The cylindrical filter utilizes the principle that surface tension in the pores of the filter prevents gas bubbles from passing through. As a result, the gas collects in the interior region of the filter and coalesces to form larger bubbles in the center of the device. The device is particularly suited for use in microgravity conditions since the swirlers induce a centrifugal force which causes liquid to move from the inner region of the filter, pass the pores, and flow through the outlet of the device while the entrained gas is trapped by the filter. The device includes a cylindrical gas storage screen which is enclosed by the cylindrical gas separation filter. The screen has pores that are larger than those of the filters. The screen prevents larger bubbles that have been formed from reaching and interfering with the pores of the gas separation filter. The device is initially filled with a gas other than that which is to be separated. This technique results in separation of the gas even before gas bubbles are present in the mixture. Initially filling the device with the dissimilar gas and preventing the gas from escaping before operation can be accomplished by sealing the dissimilar gas in the inner region of the separation device with a ruptured disc which can be ruptured when the device is activated for use.

  17. Catalyst and process development for synthesis gas conversion to isobutylene

    SciTech Connect (OSTI)

    Anthony, R.G.; Akgerman, A.

    1992-05-26T23:59:59.000Z

    The objectives of this project are to develop a new catalyst, the kinetics for this catalyst, reactor models for trickle bed, slurry and fixed bed, and simulate the performance of fixed bed trickle flow reactors, slurry flow reactors, and fixed bed gas phase reactors for conversion of a hydrogen lean synthesis gas to isobutylene.

  18. Regeneration of an aqueous solution from an acid gas absorption process by matrix stripping

    DOE Patents [OSTI]

    Rochelle, Gary T. (Austin, TX); Oyenekan, Babatunde A. (Katy, TX)

    2011-03-08T23:59:59.000Z

    Carbon dioxide and other acid gases are removed from gaseous streams using aqueous absorption and stripping processes. By replacing the conventional stripper used to regenerate the aqueous solvent and capture the acid gas with a matrix stripping configuration, less energy is consumed. The matrix stripping configuration uses two or more reboiled strippers at different pressures. The rich feed from the absorption equipment is split among the strippers, and partially regenerated solvent from the highest pressure stripper flows to the middle of sequentially lower pressure strippers in a "matrix" pattern. By selecting certain parameters of the matrix stripping configuration such that the total energy required by the strippers to achieve a desired percentage of acid gas removal from the gaseous stream is minimized, further energy savings can be realized.

  19. Statistical estimation of multiple faults in aircraft gas turbine engines

    E-Print Network [OSTI]

    Ray, Asok

    415 Statistical estimation of multiple faults in aircraft gas turbine engines S Sarkar, C Rao of multiple faults in aircraft gas-turbine engines, based on a statistical pattern recognition tool called commercial aircraft engine. Keywords: aircraft propulsion, gas turbine engines, multiple fault estimation

  20. Natural gas pipeline technology overview.

    SciTech Connect (OSTI)

    Folga, S. M.; Decision and Information Sciences

    2007-11-01T23:59:59.000Z

    The United States relies on natural gas for one-quarter of its energy needs. In 2001 alone, the nation consumed 21.5 trillion cubic feet of natural gas. A large portion of natural gas pipeline capacity within the United States is directed from major production areas in Texas and Louisiana, Wyoming, and other states to markets in the western, eastern, and midwestern regions of the country. In the past 10 years, increasing levels of gas from Canada have also been brought into these markets (EIA 2007). The United States has several major natural gas production basins and an extensive natural gas pipeline network, with almost 95% of U.S. natural gas imports coming from Canada. At present, the gas pipeline infrastructure is more developed between Canada and the United States than between Mexico and the United States. Gas flows from Canada to the United States through several major pipelines feeding U.S. markets in the Midwest, Northeast, Pacific Northwest, and California. Some key examples are the Alliance Pipeline, the Northern Border Pipeline, the Maritimes & Northeast Pipeline, the TransCanada Pipeline System, and Westcoast Energy pipelines. Major connections join Texas and northeastern Mexico, with additional connections to Arizona and between California and Baja California, Mexico (INGAA 2007). Of the natural gas consumed in the United States, 85% is produced domestically. Figure 1.1-1 shows the complex North American natural gas network. The pipeline transmission system--the 'interstate highway' for natural gas--consists of 180,000 miles of high-strength steel pipe varying in diameter, normally between 30 and 36 inches in diameter. The primary function of the transmission pipeline company is to move huge amounts of natural gas thousands of miles from producing regions to local natural gas utility delivery points. These delivery points, called 'city gate stations', are usually owned by distribution companies, although some are owned by transmission companies. Compressor stations at required distances boost the pressure that is lost through friction as the gas moves through the steel pipes (EPA 2000). The natural gas system is generally described in terms of production, processing and purification, transmission and storage, and distribution (NaturalGas.org 2004b). Figure 1.1-2 shows a schematic of the system through transmission. This report focuses on the transmission pipeline, compressor stations, and city gates.

  1. Method and system for measuring multiphase flow using multiple pressure differentials

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2001-01-01T23:59:59.000Z

    An improved method and system for measuring a multiphase flow in a pressure flow meter. An extended throat venturi is used and pressure of the multiphase flow is measured at three or more positions in the venturi, which define two or more pressure differentials in the flow conduit. The differential pressures are then used to calculate the mass flow of the gas phase, the total mass flow, and the liquid phase. The method for determining the mass flow of the high void fraction fluid flow and the gas flow includes certain steps. The first step is calculating a gas density for the gas flow. The next two steps are finding a normalized gas mass flow rate through the venturi and computing a gas mass flow rate. The following step is estimating the gas velocity in the venturi tube throat. The next step is calculating the pressure drop experienced by the gas-phase due to work performed by the gas phase in accelerating the liquid phase between the upstream pressure measuring point and the pressure measuring point in the venturi throat. Another step is estimating the liquid velocity in the venturi throat using the calculated pressure drop experienced by the gas-phase due to work performed by the gas phase. Then the friction is computed between the liquid phase and a wall in the venturi tube. Finally, the total mass flow rate based on measured pressure in the venturi throat is calculated, and the mass flow rate of the liquid phase is calculated from the difference of the total mass flow rate and the gas mass flow rate.

  2. Complex temporal and spatial patterns in nonequilibrium systems

    SciTech Connect (OSTI)

    Swinney, H.L.

    1991-09-01T23:59:59.000Z

    Dynamical systems methods are being developed and used to characterize the formation and evolution of temporal and spatial patterns in systems maintained far from equilibrium. In particular, experiments and analyses are considering electrodeposition of fractal metallic clusters, pattern formation in reaction-diffusion systems, and the primary instabilities of some fluid flows. Novel reactors have been developed to search for chemical patterns (spatial variations in the chemical composition), and sustained patterns have been found in several different one- and two-dimensional geometries. Bifurcations in these patterns are studied by varying control parameters, e.g., the concentrations of the feed chemicals or the temperature. The observed two-dimensional chemical patterns range from the stationary patterns, similar to those predicted by Turing in 1952 but not observed until 1990, to chemical turbulence, which is characterized by large numbers of defects and a rapid decay of spatial correlations. These provide general insights into the formation of spatiotemporal patterns in nonequilibrium systems.

  3. Process for separating carbon dioxide from flue gas using sweep-based membrane separation and absorption steps

    DOE Patents [OSTI]

    Wijmans, Johannes G.; Baker, Richard W.; Merkel, Timothy C.

    2012-08-21T23:59:59.000Z

    A gas separation process for treating flue gases from combustion processes, and combustion processes including such gas separation. The invention involves routing a first portion of the flue gas stream to be treated to an absorption-based carbon dioxide capture step, while simultaneously flowing a second portion of the flue gas across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas to the combustor.

  4. Fission gas release restrictor for breached fuel rod

    DOE Patents [OSTI]

    Kadambi, N. Prasad (Gaithersburg, MD); Tilbrook, Roger W. (Monroeville, PA); Spencer, Daniel R. (Unity Twp., PA); Schwallie, Ambrose L. (Greensburg, PA)

    1986-01-01T23:59:59.000Z

    In the event of a breach in the cladding of a rod in an operating liquid metal fast breeder reactor, the rapid release of high-pressure gas from the fission gas plenum may result in a gas blanketing of the breached rod and rods adjacent thereto which impairs the heat transfer to the liquid metal coolant. In order to control the release rate of fission gas in the event of a breached rod, the substantial portion of the conventional fission gas plenum is formed as a gas bottle means which includes a gas pervious means in a small portion thereof. During normal reactor operation, as the fission gas pressure gradually increases, the gas pressure interiorly of and exteriorly of the gas bottle means equalizes. In the event of a breach in the cladding, the gas pervious means in the gas bottle means constitutes a sufficient restriction to the rapid flow of gas therethrough that under maximum design pressure differential conditions, the fission gas flow through the breach will not significantly reduce the heat transfer from the affected rod and adjacent rods to the liquid metal heat transfer fluid flowing therebetween.

  5. COMPARISON OF VARIOUS FORMULATIONS OF THREEPHASE FLOW IN POROUS MEDIA

    E-Print Network [OSTI]

    , oil, and gas) flow in porous media, including phase, global, and pseudo­global pressure three­phase (e.g., water, oil, and gas) flow in porous media. We show that, under a so­called total­global pressure and two saturations without any assumption. However, it turns out that the phase and pseudo

  6. 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...

  7. Gas Viscosity at High Pressure and High Temperature

    E-Print Network [OSTI]

    Ling, Kegang

    2012-02-14T23:59:59.000Z

    Gas viscosity is one of the gas properties that is vital to petroleum engineering. Its role in the oil and gas production and transportation is indicated by its contribution in the resistance to the flow of a fluid both in porous media and pipes...

  8. Managing talent flow. 2006 Energy and Resources

    E-Print Network [OSTI]

    and market growth in mining, utilities, oil and gas have been relatively stagnant, prompting many youngManaging talent flow. 2006 Energy and Resources Talent Pulse Survey Report Consulting #12;Executive ................................................................ 13 Contents #12;1 Managing talent flow 2006 Energy and Resources Talent Pulse Survey Report 2006

  9. Quantitative supersonic flow visualization by hydraulic analogy

    E-Print Network [OSTI]

    Rani, Sarma Laxminarasimha

    1998-01-01T23:59:59.000Z

    The hydraulic analogy, which forms the basis for the phics. current investigation, can be used to study supersonic gas flows with great ease by means of a water table. As a result of the analogy, water heights in free surface water flow correspond...

  10. 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.

  11. AGGLOMERATION OF GAS HYDRATE IN A WATER-IN-OIL EMULSION: EXPERIMENTAL AND MODELING STUDIES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    AGGLOMERATION OF GAS HYDRATE IN A WATER-IN-OIL EMULSION: EXPERIMENTAL AND MODELING STUDIES Ana of gas hydrates in water-in-oil emulsion is investigated at the laboratory pilot scale on a flow loop and a spread of the Chord Length Distribution (CLD) to larger chord length. Keywords: gas hydrates, flow loop

  12. Inductively coupled plasma torch with laminar flow cooling

    DOE Patents [OSTI]

    Rayson, Gary D. (Las Cruces, NM); Shen, Yang (Las Cruces, NM)

    1991-04-30T23:59:59.000Z

    An improved inductively coupled gas plasma torch. The torch includes inner and outer quartz sleeves and tubular insert snugly fitted between the sleeves. The insert includes outwardly opening longitudinal channels. Gas flowing through the channels of the insert emerges in a laminar flow along the inside surface of the outer sleeve, in the zone of plasma heating. The laminar flow cools the outer sleeve and enables the torch to operate at lower electrical power and gas consumption levels additionally, the laminar flow reduces noise levels in spectroscopic measurements of the gaseous plasma.

  13. Analysis of well test data from gas condensate reservoirs using single-phase dry gas methods: guidelines and examples

    E-Print Network [OSTI]

    Bonilla Kalil, Jose Ricardo

    1998-01-01T23:59:59.000Z

    drop functions versus flowing time, Arun Well A-70 (second drawdown). . 141 A-49 Early-time plot: pseudopressure versus flowing time, Arun Well A-70 (third drawdown). . 145 A-50 Semilog plot: pseudopressure versus flowing time, Arun Well A-70... due to its simplicity (the saturation history is not required). Our desire is to successfully demonstrate the analysis and interpretation of well test data in gas condensate systems using the "dry gas" analog. The primary deliverable of this thesis...

  14. Serial cooling of a combustor for a gas turbine engine

    DOE Patents [OSTI]

    Abreu, Mario E. (Poway, CA); Kielczyk, Janusz J. (Escondido, CA)

    2001-01-01T23:59:59.000Z

    A combustor for a gas turbine engine uses compressed air to cool a combustor liner and uses at least a portion of the same compressed air for combustion air. A flow diverting mechanism regulates compressed air flow entering a combustion air plenum feeding combustion air to a plurality of fuel nozzles. The flow diverting mechanism adjusts combustion air according to engine loading.

  15. Landscape pattern Introduction

    E-Print Network [OSTI]

    McGarigal, Kevin

    Landscape pattern metrics Introduction Landscape ecology, if not ecology in general, is largely founded on the notion that environmen- tal patterns strongly influence ecological processes [1, 2, and these patterns interact with organism perception and behavior to drive the higher level processes of population

  16. The effect of perforation patterns upon well productivity

    E-Print Network [OSTI]

    Neale, John William

    1955-01-01T23:59:59.000Z

    )ority of reservoirs it has been observed that the oil exists originally at or near its bubble point? llhen che pressure is reduoed at the well bore, oonsiderable quantities of gas are evolved The oreation of a free gas phase in the interstioes of the porous medium... the flow of oil into the well borea The use of a direot eleotrioal analogy beoomes someuhat more diffioult when dealing with sn oil not highly undersaturated, The oreation of a free gas phase oauses severe ohanges in the resistanoe to the flow of oil...

  17. Assessment of coal bed gas prospects

    SciTech Connect (OSTI)

    Moore, T.R. [Phillips Petroleum Co., Bartlesville, OK (United States)

    1996-12-31T23:59:59.000Z

    Coal bed gas is an often overlooked source of clean, methane-rich, H{sub 2}S-free natural gas. The economic development of coal bed gas requires a knowledge of coal gas reservoir characteristics and certain necessary departures from conventional evaluation, drilling, completion, and production practices. In many ways coal seam reservoirs are truly unconventional. Most coals sufficient rank have generated large volumes of gas that may be retained depth in varying amounts through adsorption. Coal gas production can take place only when the reservoir pressure is reduced sufficiently to allow the gas to desorb. Gas flow to the well bore takes place through a hierarchy of natural fractures, not the relatively impermeable coal matrix. Economic production is dependent upon critical factors intrinsic to the reservoir, including coal petrology, gas content, internal formation stratigraphy, fracture distribution, hydrogeology, in situ stress conditions, initial reservoir pressure and pressure regime, and the presence or absence of a {open_quote}free{close_quotes} gas saturation. Further, the coal bed reservoir is readily subject to formation damage through improper drilling, completion, or production techniques. This presentation will review the data types critical to the assessment of any coal seam gas prospect, suggest an outline method for screening such prospects, and point out some possible pitfalls to be considered in any coal bed gas development project.

  18. Co-flow planar SOFC fuel cell stack

    DOE Patents [OSTI]

    Chung, Brandon W.; Pham, Ai Quoc; Glass, Robert S.

    2004-11-30T23:59:59.000Z

    A co-flow planar solid oxide fuel cell stack with an integral, internal manifold and a casing/holder to separately seal the cell. This construction improves sealing and gas flow, and provides for easy manifolding of cell stacks. In addition, the stack construction has the potential for an improved durability and operation with an additional increase in cell efficiency. The co-flow arrangement can be effectively utilized in other electrochemical systems requiring gas-proof separation of gases.

  19. Method of lift-off patterning thin films in situ employing phase change resists

    DOE Patents [OSTI]

    Bahlke, Matthias Erhard; Baldo, Marc A; Mendoza, Hiroshi Antonio

    2014-09-23T23:59:59.000Z

    Method for making a patterned thin film of an organic semiconductor. The method includes condensing a resist gas into a solid film onto a substrate cooled to a temperature below the condensation point of the resist gas. The condensed solid film is heated selectively with a patterned stamp to cause local direct sublimation from solid to vapor of selected portions of the solid film thereby creating a patterned resist film. An organic semiconductor film is coated on the patterned resist film and the patterned resist film is heated to cause it to sublime away and to lift off because of the phase change.

  20. Gas exchange in terrestrial environments comes at the cost of evaporative water loss from respiratory surfaces.

    E-Print Network [OSTI]

    Franz, Nico M.

    3477 Gas exchange in terrestrial environments comes at the cost of evaporative water loss from of gas exchange, both within and among species (Lighton, 1998; Shelton and Appel, 2001; Chown, 2002). The classical pattern is that of discontinuous gas exchange, or discontinuous gas-exchange cycles (DGC; Lighton

  1. High ratio recirculating gas compressor

    DOE Patents [OSTI]

    Weinbrecht, J.F.

    1989-08-22T23:59:59.000Z

    A high ratio positive displacement recirculating rotary compressor is disclosed. The compressor includes an integral heat exchanger and recirculation conduits for returning cooled, high pressure discharge gas to the compressor housing to reducing heating of the compressor and enable higher pressure ratios to be sustained. The compressor features a recirculation system which results in continuous and uninterrupted flow of recirculation gas to the compressor with no direct leakage to either the discharge port or the intake port of the compressor, resulting in a capability of higher sustained pressure ratios without overheating of the compressor. 10 figs.

  2. Production patterns in Eagle Ford Shale (Decline Curve Analysis) Muoz Torres, J.1

    E-Print Network [OSTI]

    Texas at Austin, University of

    , the Eagle Ford Shale (EFS) play has had a remarkable development in natural gas and oil production. EFSEG39 Production patterns in Eagle Ford Shale (Decline Curve Analysis) Muñoz Torres, J.1 javier (bcf) of natural gas and 8,049 thousand barrels of oil. Up to 2020, it is expected that natural gas

  3. Author's personal copy Numerical study of interference between simple-shape bodies in hypersonic flows

    E-Print Network [OSTI]

    Riabov, Vladimir V.

    2008 Available online 3 December 2008 Keywords: Hypersonic rarefied-gas flows Direct simulation Monte-Carlo method Flow interference Simple-shape bodies Toroidal balloon a b s t r a c t Hypersonic rarefied-gas, the configuration of subsonic flow zones), skin friction, pressure distribu- tion, lift, and drag have been found. Ó

  4. 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.

  5. Microfluidics Formation of Bubbles in a Multisection Flow-Focusing

    E-Print Network [OSTI]

    Prentiss, Mara

    Microfluidics Formation of Bubbles in a Multisection Flow-Focusing Junction Michinao Hashimoto the stable formation of trains of mono-, bi-, and tri-disperse bubbles in microfluidic flow- focusing (FF-assembly through the patterns of flow created by the bubbles. 1.1 Bubbles and Droplets in Microfluidics

  6. Combustion synthesis continuous flow reactor

    DOE Patents [OSTI]

    Maupin, G.D.; Chick, L.A.; Kurosky, R.P.

    1998-01-06T23:59:59.000Z

    The present invention is a reactor for combustion synthesis of inorganic powders. The reactor includes a reaction vessel having a length and a first end and a second end. The reaction vessel further has a solution inlet and a carrier gas inlet. The reactor further has a heater for heating both the solution and the carrier gas. In a preferred embodiment, the reaction vessel is heated and the solution is in contact with the heated reaction vessel. It is further preferred that the reaction vessel be cylindrical and that the carrier gas is introduced tangentially into the reaction vessel so that the solution flows helically along the interior wall of the reaction vessel. As the solution evaporates and combustion produces inorganic material powder, the carrier gas entrains the powder and carries it out of the reactor. 10 figs.

  7. Two-Phase Flow Simulations In a Natural Rock Fracture using the VOF Method

    SciTech Connect (OSTI)

    Crandall, Dustin; Ahmadi, Goodarz; Smith, Duane H., Bromhal, Grant

    2010-01-01T23:59:59.000Z

    Standard models of two-phase flow in porous media have been shown to exhibit several shortcomings that might be partially overcome with a recently developed model based on thermodynamic principles (Hassanizadeh and Gray, 1990). This alternative two-phase flow model contains a set of new and non-standard parameters, including specific interfacial area. By incorporating interfacial area production, destruction, and propagation into functional relationships that describe the capillary pressure and saturation, a more physical model has been developed. Niessner and Hassanizadeh (2008) have examined this model numerically and have shown that the model captures saturation hysteresis with drainage/imbibition cycles. Several static experimental studies have been performed to examine the validity of this new thermodynamically based approach; these allow the determination of static parameters of the model. To date, no experimental studies have obtained information about the dynamic parameters required for the model. A new experimental porous flow cell has been constructed using stereolithography to study two-phase flow phenomena (Crandall et al. 2008). A novel image analysis tool was developed for an examination of the evolution of flow patterns during displacement experiments (Crandall et al. 2009). This analysis tool enables the direct quantification of interfacial area between fluids by matching known geometrical properties of the constructed flow cell with locations identified as interfaces from images of flowing fluids. Numerous images were obtained from two-phase experiments within the flow cell. The dynamic evolution of the fluid distribution and the fluid-fluid interface locations were determined by analyzing these images. In this paper, we give a brief introduction to the thermodynamically based two-phase flow model, review the properties of the stereolithography flow cell, and show how the image analysis procedure has been used to obtain dynamic parameters for the numerical model. These parameters include production/destruction of interfacial area as a function of saturation and capillary pressure. Our preliminary results for primary drainage in porous media show that the specific interfacial area increased linearly with increasing gas saturation until breakthrough of the displacing gas into the exit manifold occurred.

  8. AIAA 2003-0085 Integration of RANS and LES Flow

    E-Print Network [OSTI]

    Stanford University

    investigations of highly complex flow systems, such as the aero-thermal flow through an entire aircraft gas inadequate or too expensive to be applied to a generic problem. As an example, the aero-thermal flow through-component phenomena, such as compressor/combustor instability and combus- tor/turbine hot-streak migration. Therefore

  9. Viscous exchange flows Gary P. Matson and Andrew J. Hogg

    E-Print Network [OSTI]

    Hogg, Andrew

    -based expressions for the gas mass flow rate and pressure profile in a microscale tube Phys. Fluids 24, 012005 (2012 viscosities, counter-flow within a horizontal channel, are found in many industrial and environmental settingsViscous exchange flows Gary P. Matson and Andrew J. Hogg Citation: Phys. Fluids 24, 023102 (2012

  10. 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}}.

  11. Gas sensor

    DOE Patents [OSTI]

    Schmid, Andreas K.; Mascaraque, Arantzazu; Santos, Benito; de la Figuera, Juan

    2014-09-09T23:59:59.000Z

    A gas sensor is described which incorporates a sensor stack comprising a first film layer of a ferromagnetic material, a spacer layer, and a second film layer of the ferromagnetic material. The first film layer is fabricated so that it exhibits a dependence of its magnetic anisotropy direction on the presence of a gas, That is, the orientation of the easy axis of magnetization will flip from out-of-plane to in-plane when the gas to be detected is present in sufficient concentration. By monitoring the change in resistance of the sensor stack when the orientation of the first layer's magnetization changes, and correlating that change with temperature one can determine both the identity and relative concentration of the detected gas. In one embodiment the stack sensor comprises a top ferromagnetic layer two mono layers thick of cobalt deposited upon a spacer layer of ruthenium, which in turn has a second layer of cobalt disposed on its other side, this second cobalt layer in contact with a programmable heater chip.

  12. Sensor array for toxic gas detection

    DOE Patents [OSTI]

    Stetter, Joseph R. (Naperville, IL); Zaromb, Solomon (Hinsdale, IL); Penrose, William R. (Naperville, IL)

    1987-01-01T23:59:59.000Z

    A portable instrument for use in the field in detecting and identifying a hazardous component in air or other gas including an array of small sensors which upon exposure to the gas from a pattern of electrical responses, a source of standard response patterns characteristic of various components, and microprocessor means for comparing the sensor-formed response pattern with one or more standard patterns to thereby identify the component on a display. The number of responses may be increased beyond the number of sensors by changing the operating voltage, temperature or other condition associated with one or more sensors to provide a plurality of responses from each of one or more of the sensors. In one embodiment, the instrument is capable of identifying anyone of over 50-100 hazardous components.

  13. 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.

  14. Global Natural Gas Market Trends, 2. edition

    SciTech Connect (OSTI)

    NONE

    2007-07-15T23:59:59.000Z

    The report provides an overview of major trends occurring in the natural gas industry and includes a concise look at the drivers behind recent rapid growth in gas usage and the challenges faced in meeting that growth. Topics covered include: an overview of Natural Gas including its history, the current market environment, and its future market potential; an analysis of the overarching trends that are driving a need for change in the Natural Gas industry; a description of new technologies being developed to increase production of Natural Gas; an evaluation of the potential of unconventional Natural Gas sources to supply the market; a review of new transportation methods to get Natural Gas from producing to consuming countries; a description of new storage technologies to support the increasing demand for peak gas; an analysis of the coming changes in global Natural Gas flows; an evaluation of new applications for Natural Gas and their impact on market sectors; and, an overview of Natural Gas trading concepts and recent changes in financial markets.

  15. Recovery of Water from Boiler Flue Gas

    SciTech Connect (OSTI)

    Edward Levy; Harun Bilirgen; Kwangkook Jeong; Michael Kessen; Christopher Samuelson; Christopher Whitcombe

    2008-09-30T23:59:59.000Z

    This project dealt with use of condensing heat exchangers to recover water vapor from flue gas at coal-fired power plants. Pilot-scale heat transfer tests were performed to determine the relationship between flue gas moisture concentration, heat exchanger design and operating conditions, and water vapor condensation rate. The tests also determined the extent to which the condensation processes for water and acid vapors in flue gas can be made to occur separately in different heat transfer sections. The results showed flue gas water vapor condensed in the low temperature region of the heat exchanger system, with water capture efficiencies depending strongly on flue gas moisture content, cooling water inlet temperature, heat exchanger design and flue gas and cooling water flow rates. Sulfuric acid vapor condensed in both the high temperature and low temperature regions of the heat transfer apparatus, while hydrochloric and nitric acid vapors condensed with the water vapor in the low temperature region. Measurements made of flue gas mercury concentrations upstream and downstream of the heat exchangers showed a significant reduction in flue gas mercury concentration within the heat exchangers. A theoretical heat and mass transfer model was developed for predicting rates of heat transfer and water vapor condensation and comparisons were made with pilot scale measurements. Analyses were also carried out to estimate how much flue gas moisture it would be practical to recover from boiler flue gas and the magnitude of the heat rate improvements which could be made by recovering sensible and latent heat from flue gas.

  16. Metallurgical technologies, energy conversion, and magnetohydrodynamic flows

    SciTech Connect (OSTI)

    Branover, H.; Unger, Y.

    1993-01-01T23:59:59.000Z

    The present volume discusses metallurgical applications of MHD, R D on MHD devices employing liquid working medium for process applications, electromagnetic (EM) modulation of molten metal flow, EM pump performance of superconducting MHD devices, induction EM alkali-metal pumps, a physical model for EM-driven flow in channel-induction furnaces, grain refinement in Al alloys via EM vibrational method, dendrite growth of solidifying metal in dc magnetic field, MHD for mass and heat transfer in single-crystal melt growth, inverse EM shaping, and liquid-metal MHD development in Israel. Also discussed are the embrittlement of steel by lead, an open cycle MHD disk generator, the acceleration of gas-liquid piston flows for molten-metal MHD generators, MHD flow around a cylinder, new MHD drag coefficients, liquid-metal MHD two-phase flow, and two-phase liquid gas mixers for MHD energy conversion.

  17. Long term performance of boilers using landfill gas

    SciTech Connect (OSTI)

    Gulledge, J.; Cosulich, J.; Ahmed, S.L.

    1996-11-01T23:59:59.000Z

    The US EPA estimates that approximately 600 to 700 landfills produce sufficient gas for profitable energy production in the United States. The gas from these landfills could provide enough electricity for about 3 million homes. Yet, there are only about 120 operating landfill gas to energy facilities. A lack of information on successful projects may cause part of this shortfall. This paper provides information on 4 successful projects using landfill gas fired boilers, some of which have operated over a decade. Natural gas fired boilers can be easily converted to bum landfill gas. Several modifications to Districts` boilers, described in this paper, have resulted in many years of safe and corrosion free operation. Most of the modifications are minor. Conversion can be accomplished for under $100,000 in many cases. Information on the reliability and longevity of landfill gas supplies is also provided. Gas from a given landfill is generally available over 99.5% of the time with about 5 brief flow interruptions annually. Actual data from 3 landfills document the high availability of landfill gas. To show the longevity of landfill gas flows, data from the Palos Verdes Landfill are provided. The Palos Verdes Landfill closed in 1980. The Palos Verdes. Landfill Gas to Energy Facility is currently producing over 8 megawatts. Landfill gas pretreatment is not required for boilers. In cases where the landfill gas is being piped offsite, it is usually cost effective to dehydrate the landfill gas. Landfill gas bums cleaner than natural gas. NO{sub x} emissions from landfill gas fired boilers are lower because of the carbon dioxide in the landfill gas. Trace organic destruction efficiency is usually over 99% in landfill gas fired boilers. In addition, flare emissions are eliminated when landfill gas is used to displace fossil fuels in boilers.

  18. Technically recoverable Devonian shale gas in Ohio

    SciTech Connect (OSTI)

    Kuushraa, V.A.; Wicks, D.E.; Sawyer, W.K.; Esposito, P.R.

    1983-07-01T23:59:59.000Z

    The technically recoverable gas from Devonian shale (Lower and Middle Huron) in Ohio is estimated to range from 6.2 to 22.5 Tcf, depending on the stimulation method and pattern size selected. This estimate of recovery is based on the integration of the most recent data and research on the Devonian Age gas-bearing shales of Ohio. This includes: (1) a compilation of the latest geologic and reservoir data for the gas in-place; (2) analysis of the key productive mechanisms; and, (3) examination of alternative stimulation and production strategies for most efficiently recovering this gas. Beyond a comprehensive assembly of the data and calculation of the technically recoverable gas, the key findings of this report are as follows: a substantial volume of gas is technically recoverable, although advanced (larger scale) stimulation technology will be required to reach economically attractive gas production rates in much of the state; well spacing in certain of the areas can be reduced by half from the traditional 150 to 160 acres per well without severely impairing per-well gas recovery; and, due to the relatively high degree of permeability anisotropy in the Devonian shales, a rectangular, generally 3 by 1 well pattern leads to optimum recovery. Finally, although a consistent geological interpretation and model have been constructed for the Lower and Middle Huron intervals of the Ohio Devonian shale, this interpretation is founded on limited data currently available, along with numerous technical assumptions that need further verification. 11 references, 21 figures, 32 tables.

  19. NATURAL GAS MARKET ASSESSMENT

    E-Print Network [OSTI]

    CALIFORNIA ENERGY COMMISSION NATURAL GAS MARKET ASSESSMENT PRELIMINARY RESULTS In Support.................................................................................... 6 Chapter 2: Natural Gas Demand.................................................................................................. 10 Chapter 3: Natural Gas Supply

  20. Direct numerical simulation of pattern formation in subaqueous sediment

    E-Print Network [OSTI]

    Kidanemariam, Aman G

    2014-01-01T23:59:59.000Z

    We present results of direct numerical simulation of incompressible fluid flow over a thick bed of mobile, spherically-shaped particles. The algorithm is based upon the immersed boundary technique for fluid-solid coupling and uses a soft-sphere model for the solid-solid contact. Two parameter points in the laminar flow regime are chosen, leading to the emergence of sediment patterns classified as `small dunes', while one case under turbulent flow conditions leads to `vortex dunes' with significant flow separation on the lee side. Wavelength, amplitude and propagation speed of the patterns extracted from the spanwise-averaged fluid-bed interface are found to be consistent with available experimental data. The particle transport rates are well represented by available empirical models for flow over a plane sediment bed in both the laminar and the turbulent regimes.

  1. Statistically steady measurements of Rayleigh-Taylor mixing in a gas channel 

    E-Print Network [OSTI]

    Banerjee, Arindam

    2006-10-30T23:59:59.000Z

    A novel gas channel experiment was constructed to study the development of high Atwood number Rayleigh-Taylor mixing. Two gas streams, one containing air and the other containing helium-air mixture, flow parallel to each ...

  2. Interaction of Turing and flow-induced chemical instabilities

    SciTech Connect (OSTI)

    Dawson, S.P. (Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)); Lawniczak, A. (Department of Mathematics and Statistics, University of Guelph, Guelph, Ontario N1G 2W1 (Canada) Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)); Kapral, R. (Chemical Physics Theory Group, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 1A1 (Canada))

    1994-04-01T23:59:59.000Z

    The interaction between the Turing instability and the instability induced by a differential flow is studied in the Selkov model. Both instabilities give rise to the formation of spatial patterns, and for a range of parameter values, these patterns can compete. The effect of anisotropic diffusion on the pattern formation process is investigated. Stripes with different orientations that travel with time and the suppression of patterns due to a competition of both instabilities are observed.

  3. Excitability in high-Lewis number premixed gas combustion

    SciTech Connect (OSTI)

    Pearlman, H. [NASA Lewis Research Center, Cleveland, OH (United States)] [NASA Lewis Research Center, Cleveland, OH (United States)

    1997-05-01T23:59:59.000Z

    The dynamical behavior of freely-propagating premixed gas flames in tubes is studied experimentally in the high-Lewis number (Le) regime using a mixture of butane and oxygen diluted with helium (Le {approx} 4.0). Steadily-propagating, stable flames develop traveling wave and spinning instabilities as the stoichiometry of the mixture approaches the lean flammability limit. These instabilities occur spontaneously and form target patterns and rotating spiral waves, bearing remarkable similarity with patterns observed in excitable media. Additional experiments are conducted on burner-stabilized flames and indicate that these instabilities also occur in three common air-diluted mixtures with smaller Le`s than their helium-diluted counterparts. Specifically, the instabilities are observed in stoichiometric and lean mixtures of butane-air (Le {approx} 2.1), propane-air (Le {approx} 1.9), and stoichiometric and rich mixtures of methane-air (Le {approx} 1.1) at sufficiently low mixture flow rates. Both experiments confirm model predictions that increasing conductive loss lowers the critical Le required for onset of instability.

  4. 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.

  5. Hydrate Control for Gas Storage Operations

    SciTech Connect (OSTI)

    Jeffrey Savidge

    2008-10-31T23:59:59.000Z

    The overall objective of this project was to identify low cost hydrate control options to help mitigate and solve hydrate problems that occur in moderate and high pressure natural gas storage field operations. The study includes data on a number of flow configurations, fluids and control options that are common in natural gas storage field flow lines. The final phase of this work brings together data and experience from the hydrate flow test facility and multiple field and operator sources. It includes a compilation of basic information on operating conditions as well as candidate field separation options. Lastly the work is integrated with the work with the initial work to provide a comprehensive view of gas storage field hydrate control for field operations and storage field personnel.

  6. Gas permeability of carbon aerogels

    SciTech Connect (OSTI)

    Kong, F.; LeMay, J.D.; Hulsey, S.S.; Alviso, C.T.; Pekala, R.W. (Chemistry and Materials Science Department, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States))

    1993-12-01T23:59:59.000Z

    Carbon aerogels are synthesized via the aqueous polycondensation of resorcinol with formaldehyde, followed by supercritical drying and subsequent pyrolysis at 1050 [degree]C. As a result of their interconnected porosity, ultrafine cell/pore size, and high surface area, carbon aerogels have many potential applications such as supercapacitors, battery electrodes, catalyst supports, and gas filters. The performance of carbon aerogels in the latter two applications depends on the permeability or gas flow conductance in these materials. By measuring the pressure differential across a thin specimen and the nitrogen gas flow rate in the viscous regime, the permeability of carbon aerogels was calculated from equations based upon Darcy's law. Our measurements show that carbon aerogels have permeabilities on the order of 10[sup [minus]12] to 10[sup [minus]10] cm[sup 2] over the density range from 0.05--0.44 g/cm[sup 3]. Like many other aerogel properties, the permeability of carbon aerogels follows a power law relationship with density, reflecting differences in the average mesopore size. Comparing the results from this study with the permeability of silica aerogels reported by other workers, we found that the permeability of aerogels is governed by a simple universal flow equation. This paper discusses the relationship between permeability, pore size, and density in carbon aerogels.

  7. Gas separation process using membranes with permeate sweep to remove CO.sub.2 from gaseous fuel combustion exhaust

    DOE Patents [OSTI]

    Wijmans Johannes G. (Menlo Park, CA); Merkel, Timothy C. (Menlo Park, CA); Baker, Richard W. (Palo Alto, CA)

    2012-05-15T23:59:59.000Z

    A gas separation process for treating exhaust gases from the combustion of gaseous fuels, and gaseous fuel combustion processes including such gas separation. The invention involves routing a first portion of the exhaust stream to a carbon dioxide capture step, while simultaneously flowing a second portion of the exhaust gas stream across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas back to the combustor.

  8. 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...

  9. Autothermal production of synthesis gas

    SciTech Connect (OSTI)

    Lewis, J.L.

    1987-05-19T23:59:59.000Z

    An autothermal reactor is described for the production of a synthesis gas in which both primary reforming and secondary reforming are achieved at a high level of efficiency. The method comprises a heat exchange chamber having a first portion and a second portion, a first inlet connected to the heat exchange chamber for the introduction of steam and feed gas to the heat exchange chamber, reaction tubes mounted within the first portion of the heat exchanger chamber at a location spaced longitudinally from the first inlet in communication with the first inlet and in non-concentric relationship therewith so as to provide a flow path for the steam and feed gas from the first inlet through the plurality of reaction tubes.

  10. Georgia Tech Dangerous Gas

    E-Print Network [OSTI]

    Sherrill, David

    1 Georgia Tech Dangerous Gas Safety Program March 2011 #12;Georgia Tech Dangerous Gas Safety.......................................................................................................... 5 6. DANGEROUS GAS USAGE REQUIREMENTS................................................. 7 6.1. RESTRICTED PURCHASE/ACQUISITION RULES: ................................................ 7 7. FLAMMABLE GAS

  11. Process and system for removing impurities from a gas

    DOE Patents [OSTI]

    Henningsen, Gunnar; Knowlton, Teddy Merrill; Findlay, John George; Schlather, Jerry Neal; Turk, Brian S

    2014-04-15T23:59:59.000Z

    A fluidized reactor system for removing impurities from a gas and an associated process are provided. The system includes a fluidized absorber for contacting a feed gas with a sorbent stream to reduce the impurity content of the feed gas; a fluidized solids regenerator for contacting an impurity loaded sorbent stream with a regeneration gas to reduce the impurity content of the sorbent stream; a first non-mechanical gas seal forming solids transfer device adapted to receive an impurity loaded sorbent stream from the absorber and transport the impurity loaded sorbent stream to the regenerator at a controllable flow rate in response to an aeration gas; and a second non-mechanical gas seal forming solids transfer device adapted to receive a sorbent stream of reduced impurity content from the regenerator and transfer the sorbent stream of reduced impurity content to the absorber without changing the flow rate of the sorbent stream.

  12. ASIAN SYMPOSIUM ON VISUALIZATION, 2003 Visualizing Heterogeneous Flows in Micro Fluidic Devices

    E-Print Network [OSTI]

    Cubaud, Thomas

    with interesting practical applications in enhanced oil recovery, heat pipes, and micro methanol fuel cells. Gas. Visualizing two-phase flow The transport of gas bubbles in polygonal microchannels is a hydrodynamic problem

  13. Controlled pilot oxidizer for a gas turbine combustor

    DOE Patents [OSTI]

    Laster, Walter R. (Oviedo, FL); Bandaru, Ramarao V. (Greer, SC)

    2010-07-13T23:59:59.000Z

    A combustor (22) for a gas turbine (10) includes a main burner oxidizer flow path (34) delivering a first portion (32) of an oxidizer flow (e.g., 16) to a main burner (28) of the combustor and a pilot oxidizer flow path (38) delivering a second portion (36) of the oxidizer flow to a pilot (30) of the combustor. The combustor also includes a flow controller (42) disposed in the pilot oxidizer flow path for controlling an amount of the second portion delivered to the pilot.

  14. Carbon ion pump for removal of carbon dioxide from combustion gas and other gas mixtures

    DOE Patents [OSTI]

    Aines, Roger D.; Bourcier, William L.

    2014-08-19T23:59:59.000Z

    A novel method and system of separating carbon dioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbon dioxide gas, permitting carbon dioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.

  15. Carbon ion pump for removal of carbon dioxide from combustion gas and other gas mixtures

    DOE Patents [OSTI]

    Aines, Roger D. (Livermore, CA); Bourcier, William L. (Livermore, CA)

    2010-11-09T23:59:59.000Z

    A novel method and system of separating carbon dioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbon dioxide gas, permitting carbon dioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.

  16. Dynamics of evaporative colloidal patterning

    E-Print Network [OSTI]

    C. Nadir Kaplan; Ning Wu; Shreyas Mandre; Joanna Aizenberg; L. Mahadevan

    2014-12-04T23:59:59.000Z

    Drying suspensions often leave behind complex patterns of particulates, as might be seen in the coffee stains on a table. Here we consider the dynamics of periodic band or uniform solid film formation on a vertical plate suspended partially in a drying colloidal solution. Direct observations allow us to visualize the dynamics of the band and film deposition, and the transition in between when the colloidal concentration is varied. A minimal theory of the liquid meniscus motion along the plate reveals the dynamics of the banding and its transition to the filming as a function of the ratio of deposition and evaporation rates. We also provide a complementary multiphase model of colloids dissolved in the liquid, which couples the inhomogeneous evaporation at the evolving meniscus to the fluid and particulate flows and the transition from a dilute suspension to a porous plug. This allows us to determine the concentration dependence of the bandwidth and the deposition rate. Together, our findings allow for the control of drying-induced patterning as a function of the colloidal concentration and evaporation rate.

  17. Surface Signature of Flow Past a Sphere at Moderate Reynolds Numbers

    E-Print Network [OSTI]

    Shao, Qi

    2014-04-29T23:59:59.000Z

    . The flow shows a planar symmetric pattern with vortex shedding. When Reynolds number increases to 500, the flow becomes more chaotic and loses its planar symmetry. At Reynolds number of 500, highly organized periodic surface signatures appear on the shear...

  18. Energy Efficient Process Heating: Managing Air Flow Kevin Carpenter and Kelly Kissock

    E-Print Network [OSTI]

    Kissock, Kelly

    temperature and decreased combustion gas mass flow rate. The method for calculating savings from preheating flow include minimizing combustion air, preheating combustion air, minimizing ventilation air from minimizing combustion air accounts for improvement in efficiency from increased combustion

  19. An unstructured finite volume simulator for multiphase flow through fractured-porous media

    E-Print Network [OSTI]

    Bajaj, Reena

    2009-01-01T23:59:59.000Z

    Modeling of multiphase flow in fractured media plays an integral role in management and performance prediction of oil and gas reserves. Geological characterization and nmultiphase flow simulations in fractured media are ...

  20. 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...

  1. Gas turbine topping combustor

    DOE Patents [OSTI]

    Beer, Janos (Winchester, MA); Dowdy, Thomas E. (Orlando, FL); Bachovchin, Dennis M. (Delmont, PA)

    1997-01-01T23:59:59.000Z

    A combustor for burning a mixture of fuel and air in a rich combustion zone, in which the fuel bound nitrogen in converted to molecular nitrogen. The fuel rich combustion is followed by lean combustion. The products of combustion from the lean combustion are rapidly quenched so as to convert the fuel bound nitrogen to molecular nitrogen without forming NOx. The combustor has an air radial swirler that directs the air radially inward while swirling it in the circumferential direction and a radial fuel swirler that directs the fuel radially outward while swirling it in the same circumferential direction, thereby promoting vigorous mixing of the fuel and air. The air inlet has a variable flow area that is responsive to variations in the heating value of the fuel, which may be a coal-derived fuel gas. A diverging passage in the combustor in front of a bluff body causes the fuel/air mixture to recirculate with the rich combustion zone.

  2. Gas turbine cooling system

    DOE Patents [OSTI]

    Bancalari, Eduardo E. (Orlando, FL)

    2001-01-01T23:59:59.000Z

    A gas turbine engine (10) having a closed-loop cooling circuit (39) for transferring heat from the hot turbine section (16) to the compressed air (24) produced by the compressor section (12). The closed-loop cooling system (39) includes a heat exchanger (40) disposed in the flow path of the compressed air (24) between the outlet of the compressor section (12) and the inlet of the combustor (14). A cooling fluid (50) may be driven by a pump (52) located outside of the engine casing (53) or a pump (54) mounted on the rotor shaft (17). The cooling circuit (39) may include an orifice (60) for causing the cooling fluid (50) to change from a liquid state to a gaseous state, thereby increasing the heat transfer capacity of the cooling circuit (39).

  3. Gas block mechanism for water removal in fuel cells

    DOE Patents [OSTI]

    Issacci, Farrokh; Rehg, Timothy J.

    2004-02-03T23:59:59.000Z

    The present invention is directed to apparatus and method for cathode-side disposal of water in an electrochemical fuel cell. There is a cathode plate. Within a surface of the plate is a flow field comprised of interdigitated channels. During operation of the fuel cell, cathode gas flows by convection through a gas diffusion layer above the flow field. Positioned at points adjacent to the flow field are one or more porous gas block mediums that have pores sized such that water is sipped off to the outside of the flow field by capillary flow and cathode gas is blocked from flowing through the medium. On the other surface of the plate is a channel in fluid communication with each porous gas block mediums. The method for water disposal in a fuel cell comprises installing the cathode plate assemblies at the cathode sides of the stack of fuel cells and manifolding the single water channel of each of the cathode plate assemblies to the coolant flow that feeds coolant plates in the stack.

  4. Anisotropic electro-osmotic flow over superhydrophobic surfaces

    E-Print Network [OSTI]

    Bazant, Martin Z.

    Patterned surfaces with large effective slip lengths, such as super-hydrophobic surfaces containing trapped gas bubbles, have the potential to greatly enhance electrokinetic phenomena. Existing theories assume either ...

  5. 2566 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 5, OCTOBER 2008 Quantitative Analysis of Gas Circuit Breaker

    E-Print Network [OSTI]

    Basse, Nils Plesner

    --Understanding the dynamic processes governing gas circuit breaker physics is crucial in order to continue to improve short, especially those induced at flow reversal where the gas flow between the arc zone and heating volume changes2566 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 5, OCTOBER 2008 Quantitative Analysis of Gas

  6. Shale Gas and Climate Targets: Can They Be Reconciled?

    E-Print Network [OSTI]

    Pedersen, Tom

    deposits flows poorly and requires new advances in hori- zontal drilling and rock fracturing to improve gas extraction rates. Hydraulic fracturing uses a water, sand, and chemical mixture pumped under high pressure

  7. Business Case for Compressed Natural Gas in Municipal Fleets

    SciTech Connect (OSTI)

    Johnson, C.

    2010-06-01T23:59:59.000Z

    This report describes how NREL used the CNG Vehicle and Infrastructure Cash-Flow Evaluation (VICE) model to establish guidance for fleets making decisions about using compressed natural gas.

  8. Low differential pressure and multiphase flow measurements by means of differential pressure devices

    E-Print Network [OSTI]

    Justo, Hernandez Ruiz,

    2004-11-15T23:59:59.000Z

    performance in the gas mass flow rate estimation was exhibited by the slotted and standard plates for the air-water flow, while poor results were obtained for the air-oil and air-water oil flows. The performance of all the flow meter tested in the analysis...

  9. Gas Separation With Graphene Membranes By Will Soutter

    E-Print Network [OSTI]

    Bunch, Scott

    applications including fuel cells, batteries, gas sensors and gas purification. The materials of carbon atoms, covalently bonded in a regular hexagonal pattern. Graphite is made up of many stacked graphene sheets, and graphene was first isolated by removing a single sheet from a graphite crystal

  10. The Effect of High Rotational Speed on the Performance of Straight-through Labyrinth Seals for Compressible and Incompressible Flow 

    E-Print Network [OSTI]

    Obidigbo, Ekene R.

    2012-07-16T23:59:59.000Z

    geometries ....................................................................................... 11 Figure 7: Flow pattern with single large vortex, (Case 4, Air, Re=1000, w=0m/s) ......... 18 Figure 8: Flow pattern with double large vortices..., (Case 5, H20, RE=1000, w=350m/s) ................................................................................ 19 Figure 9: Streamline pattern (Case 3, water, cavity 1) ..................................................... 20 Figure 10: Streamline...

  11. TANK MIXING STUDY WITH FLOW RECIRCULATION

    SciTech Connect (OSTI)

    Lee, S.

    2014-06-25T23:59:59.000Z

    The primary objective of this work is to quantify the mixing time when two miscible fluids are mixed by one recirculation pump and to evaluate adequacy of 2.5 hours of pump recirculation to be considered well mixed in SRS tanks, JT-71/72. The work scope described here consists of two modeling analyses. They are the steady state flow pattern analysis during pump recirculation operation of the tank liquid and transient species transport calculations based on the initial steady state flow patterns. The modeling calculations for the mixing time are performed by using the 99% homogeneity criterion for the entire domain of the tank contents.

  12. Self-erasing and rewritable wettability patterns on ZnO thin films

    SciTech Connect (OSTI)

    Kekkonen, Ville; Hakola, Antti; Kajava, Timo; Ras, Robin H. A. [Department of Applied Physics, Aalto University, P.O. Box 15100, FI-00076 Aalto, Espoo (Finland); Sahramo, Elina; Malm, Jari; Karppinen, Maarit [Department of Chemistry, Aalto University, P.O. Box 16100, FI-00076 Aalto, Espoo (Finland)

    2010-07-26T23:59:59.000Z

    Self-erasing patterns allow a substrate to be patterned multiple times or could store temporary information for secret communications, and are mostly based on photochromic molecules to change the color of the pattern. Herein we demonstrate self-erasing patterns of wettability on thin ZnO films made by atomic layer deposition. Hydrophilic patterns are written using UV light and decay spontaneously, i.e. become hydrophobic, or are erased aided by vacuum conditions or heat. We demonstrate that these patterns can be applied for channels to confine flow of water without physical walls.

  13. GAS PIPELINE PIGABILITY

    SciTech Connect (OSTI)

    Ted Clark; Bruce Nestleroth

    2004-04-01T23:59:59.000Z

    In-line inspection equipment is commonly used to examine a large portion of the long distance transmission pipeline system that transports natural gas from well gathering points to local distribution companies. A piece of equipment that is inserted into a pipeline and driven by product flow is called a ''pig''. Using this term as a base, a set of terms has evolved. Pigs that are equipped with sensors and data recording devices are called ''intelligent pigs''. Pipelines that cannot be inspected using intelligent pigs are deemed ''unpigable''. But many factors affect the passage of a pig through a pipeline, or the ''pigability''. The pigability pipeline extend well beyond the basic need for a long round hole with a means to enter and exit. An accurate assessment of pigability includes consideration of pipeline length, attributes, pressure, flow rate, deformation, cleanliness, and other factors as well as the availability of inspection technology. All factors must be considered when assessing the appropriateness of ILI to assess specific pipeline threats.

  14. Gas Test Loop Booster Fuel Hydraulic Testing

    SciTech Connect (OSTI)

    Gas Test Loop Hydraulic Testing Staff

    2006-09-01T23:59:59.000Z

    The Gas Test Loop (GTL) project is for the design of an adaptation to the Advanced Test Reactor (ATR) to create a fast-flux test space where fuels and materials for advanced reactor concepts can undergo irradiation testing. Incident to that design, it was found necessary to make use of special booster fuel to enhance the neutron flux in the reactor lobe in which the Gas Test Loop will be installed. Because the booster fuel is of a different composition and configuration from standard ATR fuel, it is necessary to qualify the booster fuel for use in the ATR. Part of that qualification is the determination that required thermal hydraulic criteria will be met under routine operation and under selected accident scenarios. The Hydraulic Testing task in the GTL project facilitates that determination by measuring flow coefficients (pressure drops) over various regions of the booster fuel over a range of primary coolant flow rates. A high-fidelity model of the NW lobe of the ATR with associated flow baffle, in-pile-tube, and below-core flow channels was designed, constructed and located in the Idaho State University Thermal Fluids Laboratory. A circulation loop was designed and constructed by the university to provide reactor-relevant water flow rates to the test system. Models of the four booster fuel elements required for GTL operation were fabricated from aluminum (no uranium or means of heating) and placed in the flow channel. One of these was instrumented with Pitot tubes to measure flow velocities in the channels between the three booster fuel plates and between the innermost and outermost plates and the side walls of the flow annulus. Flow coefficients in the range of 4 to 6.5 were determined from the measurements made for the upper and middle parts of the booster fuel elements. The flow coefficient for the lower end of the booster fuel and the sub-core flow channel was lower at 2.3.

  15. Hot gas filter and system assembly

    DOE Patents [OSTI]

    Lippert, T.E.; Palmer, K.M.; Bruck, G.J.; Alvin, M.A.; Smeltzer, E.E.; Bachovchin, D.M.

    1999-08-31T23:59:59.000Z

    A filter element is described for separating fine dirty particles from a hot gas. The filter element comprises a first porous wall and a second porous wall. Each porous wall has an outer surface and an inner surface. The first and second porous walls being coupled together thereby forming a substantially closed figure and open at one end. The open end is formed to be coupled to a hot gas clean up system support structure. The first and second porous walls define a channel beginning at the open end and terminate at the closed end through which a filtered clean gas can flow through and out into the clean gas side of a hot gas clean up system. 8 figs.

  16. Energy usage in oil and gas extraction

    SciTech Connect (OSTI)

    Honeycutt, B.D.

    1991-05-01T23:59:59.000Z

    This report was prepared in partial fulfillment of Subcontract No. C90-103207 by Baxter D. Honeycutt, P.E., Richardson Texas, for the Idaho National Engineering Laboratory (INEL) and the US DOE, INEL requirements, for the requested report were outlined by letter dated September 4, 1990, included the following: process flow diagrams and descriptive discussions of technical operations; mass and energy balances; a summary of energy-saving opportunities with the cross-cutting technologies emphasized; trends of oil and gas production versus energy expended to achieve new production; conclusions and recommendations for future research. The National Energy Account (NEA) data on energy usage in oil and gas related extraction processes are reproduced for reference. Energy cost and production are given for oil and gas well drilling, crude oil and production, national gas production, and natural gas liquid production.

  17. 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.

  18. 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.

  19. CHARACTERISTICS OF SOLAR MERIDIONAL FLOWS DURING SOLAR CYCLE 23

    SciTech Connect (OSTI)

    Basu, Sarbani [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States); Antia, H. M., E-mail: sarbani.basu@yale.ed, E-mail: antia@tifr.res.i [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India)

    2010-07-01T23:59:59.000Z

    We have analyzed available full-disk data from the Michelson Doppler Imager on board SOHO using the 'ring diagram' technique to determine the behavior of solar meridional flows over solar cycle 23 in the outer 2% of the solar radius. We find that the dominant component of meridional flows during solar maximum was much lower than that during the minima at the beginning of cycles 23 and 24. There were differences in the flow velocities even between the two minima. The meridional flows show a migrating pattern with higher-velocity flows migrating toward the equator as activity increases. Additionally, we find that the migrating pattern of the meridional flow matches those of sunspot butterfly diagram and the zonal flows in the shallow layers. A high-latitude band in meridional flow appears around 2004, well before the current activity minimum. A Legendre polynomial decomposition of the meridional flows shows that the latitudinal pattern of the flow was also different during the maximum as compared to that during the two minima. The different components of the flow have different time dependences, and the dependence is different at different depths.

  20. Simulation of Combustion and Thermal Flow in an Industrial Boiler

    E-Print Network [OSTI]

    Saripalli, R.; Wang, T.; Day, B.

    2005-01-01T23:59:59.000Z

    insight into the detailed thermal-flow and combustion in the boiler and showing possible reasons for superheater tube rupture. The exhaust gas temperature is consistent with the actual results from the infrared thermograph inspection....

  1. Gas turbine power plant with supersonic shock compression ramps

    DOE Patents [OSTI]

    Lawlor, Shawn P. (Bellevue, WA); Novaresi, Mark A. (San Diego, CA); Cornelius, Charles C. (Kirkland, WA)

    2008-10-14T23:59:59.000Z

    A gas turbine engine. The engine is based on the use of a gas turbine driven rotor having a compression ramp traveling at a local supersonic inlet velocity (based on the combination of inlet gas velocity and tangential speed of the ramp) which compresses inlet gas against a stationary sidewall. The supersonic compressor efficiently achieves high compression ratios while utilizing a compact, stabilized gasdynamic flow path. Operated at supersonic speeds, the inlet stabilizes an oblique/normal shock system in the gasdynamic flow path formed between the rim of the rotor, the strakes, and a stationary external housing. Part load efficiency is enhanced by use of a lean pre-mix system, a pre-swirl compressor, and a bypass stream to bleed a portion of the gas after passing through the pre-swirl compressor to the combustion gas outlet. Use of a stationary low NOx combustor provides excellent emissions results.

  2. Fuel cell generator containing a gas sealing means

    DOE Patents [OSTI]

    Makiel, Joseph M. (Monroeville, PA)

    1987-01-01T23:59:59.000Z

    A high temperature solid electrolyte electrochemical generator is made, operating with flowing fuel gas and oxidant gas, the generator having a thermal insulation layer, and a sealing means contacting or contained within the insulation, where the sealing means is effective to control the contact of the various gases utilized in the generator.

  3. Neutral gas modeling in divertors Charles F. F. Karney

    E-Print Network [OSTI]

    Karney, Charles

    that the hydrogen fuel in not diluted. The major constraints on the operation of the divertor are that it should: for example, in the "gas target" divertor, the plasma flows into a gas cell and a high-Z element radiates away code, the evaluation of erosion rates, impurities influx, etc., and the evaluation of diagnostic

  4. Using NMR to Validate First-Principles Granular Flow Equations

    E-Print Network [OSTI]

    D. Candela; C. Huan; K. Facto; R. Wang; R. W. Mair; R. L. Walsworth

    2005-10-23T23:59:59.000Z

    Nuclear magnetic resonance (NMR) experiments are described for two granular-flow systems, the vibrofluidized bed and the gas-fluidized bed. Using pulsed field gradient, magnetic resonance imaging, and hyperpolarized gas NMR, detailed information is obtained for the density and motions of both grains and interstitial gas. For the vibrofluidized bed, the granular temperature profile is measured and compared with a first-principles formulation of granular hydrodynamics. For the gas-fluidized bed, dynamic correlations in the grain density are used to measure the bubble velocity and hyperpolarized xenon gas NMR is used to measure the bubble-emulsion exchange rate. A goal of these measurements is to verify in earth gravity first-principles theories of granular flows, which then can be used to make concrete predictions for granular flows in reduced gravity.

  5. A study of water driven oil encroachment into gas caps

    E-Print Network [OSTI]

    Ritch, Harlan J

    1958-01-01T23:59:59.000Z

    (frequently thin and commonly referred to as an oil rim). Prior to the introduction of sound conservation practices, large quantities of gas were often produced and vented by operators seeking to induce a flow of oil into wells initially productive only.... : "The Prediction of Oil Recovery by Water Flood, " Seconder Recover of Oil in the United States, API (1950), Second Edition, 160. Elliott, J. K. : "The Effect of Initial Gas Content and Distribution on the Residual Gas Content of Cores after Water...

  6. ESP/rotary gas separator duo found to optimize production

    SciTech Connect (OSTI)

    Jacobs, G.H.

    1986-11-01T23:59:59.000Z

    A field test conducted on a low-volume waterflood well in West Texas equipped with an electric submersible pump (ESP) proved to rotary gas separator (RGS) to be more efficient than conventional reverse flow gas separators, achieving gas separation efficiencies close to 90%. Further, the RGS increased the run time of the ESP, thus lowering the wellbore fluid level and increasing oil production. The one drawback found is that RGSs can be susceptible to fluid erosion.

  7. Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

  8. Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

  9. Measurement and analysis of gas turbine blade endwall heat transfer

    E-Print Network [OSTI]

    Lee, Joon Ho

    2001-01-01T23:59:59.000Z

    the aerodynamic flow and external heat transfer distribution around the airfoils and end-wall surfaces. A stationary 5 vane linear cascade is designed and developed to investigate gas turbine blade endwall heat transfer and flow. The test cascade is instrumented...

  10. Visualizing flow patterns in coupled geomechanical simulation using streamlines

    E-Print Network [OSTI]

    Parihar, Prannay

    2009-05-15T23:59:59.000Z

    Reservoir geomechanics is a production induced phenomena that is experienced in large number of fields around the world. Hydrocarbon production changes the pore pressure which in turn alters the in-situ stress state. For reservoirs that are either...

  11. Microgravity flow pattern identification using void fraction signals

    E-Print Network [OSTI]

    Valota, Luca

    2005-08-29T23:59:59.000Z

    is important for engineering correlations of heat and mass transfer, pressure drop, and wall shear. However, it is somewhat subjective since it is mostly defined by experimental observation, resulting in an approximate and equivocal definition. Thus...

  12. Sandia Energy - Magnetically Stimulated Flow Patterns Offer Strategy...

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

    said, the technology could be practical in problems ranging from reactor cooling to microfluidics, a multidisciplinary field used, for example, in designing systems that handle...

  13. Sandia Energy - Magnetically Stimulated Flow Patterns Offer Strategy for

    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 PossibleRadiationImplementing Nonlinear757Kelley Ruehl Home Kelley RuehlHeat-Transfer Problems

  14. Modeling effects of diffusion and gravity drainage on oil recovery in naturally fractured reservoirs under gas injection

    E-Print Network [OSTI]

    Jamili, Ahmad

    2010-04-22T23:59:59.000Z

    Gas injection in naturally fractured reservoirs maintains the reservoir pressure, and increases oil recovery primarily by gravity drainage and to a lesser extent by mass transfer between the flowing gas in the fracture and the porous matrix...

  15. A Simple Method to Continuous Measurement of Energy Consumption of Tank Less Gas Water Heaters for Commercial Buildings

    E-Print Network [OSTI]

    Yamaha, M.; Fujita, M.; Miyoshi, T.

    2006-01-01T23:59:59.000Z

    energy consumptions of hot water supply in restaurants or residential houses are large amount, guidelines for optimal design are not presented. measurements of energy consumption of tank less gas water heaters very difficult unless gas flow meters...

  16. Fault detection and isolation in aircraft gas turbine engines. Part 1: underlying concept

    E-Print Network [OSTI]

    Ray, Asok

    307 Fault detection and isolation in aircraft gas turbine engines. Part 1: underlying concept: aircraft propulsion, gas turbine engines, fault detection and isolation, statistical pattern recognition 1 INTRODUCTION Performance and reliability of aircraft gas turbine engines gradually deteriorate over the service

  17. Observer Design for Gas Lifted Oil Wells Ole Morten Aamo, Gisle Otto Eikrem, Hardy Siahaan, and Bjarne Foss

    E-Print Network [OSTI]

    Foss, Bjarne A.

    Observer Design for Gas Lifted Oil Wells Ole Morten Aamo, Gisle Otto Eikrem, Hardy Siahaan flow systems is an area of increasing interest for the oil and gas industry. Oil wells with highly related to oil and gas wells exist, and in this study, unstable gas lifted wells will be the area

  18. Gas Storage Act (Illinois)

    Broader source: Energy.gov [DOE]

    Any corporation which is engaged in or desires to engage in, the distribution, transportation or storage of natural gas or manufactured gas, which gas, in whole or in part, is intended for ultimate...

  19. Gas Companies Program (Tennessee)

    Broader source: Energy.gov [DOE]

    The Gas Companies program is a set of rules that encourage the development of the natural gas industry in Tennessee. They empower gas companies to lay piped and extend conductors through the...

  20. Gas Utilities (Maine)

    Broader source: Energy.gov [DOE]

    Rules regarding the production, sale, and transfer of manufactured gas will also apply to natural gas. This section regulates natural gas utilities that serve ten or more customers, more than one...

  1. Gas Utilities (New York)

    Broader source: Energy.gov [DOE]

    This chapter regulates natural gas utilities in the State of New York, and describes standards and procedures for gas meters and accessories, gas quality, line and main extensions, transmission and...

  2. Future of Natural Gas

    Office of Environmental Management (EM)

    of Natural Gas Bill Eisele, CEM SC Electric & Gas Co Hosted by: FEDERAL UTILITY PARTNERSHIP WORKING GROUP SEMINAR November 5-6, 2014 Cape Canaveral. Florida Agenda * Gas Facts *...

  3. Industrial Gas Turbines

    Broader source: Energy.gov [DOE]

    A gas turbine is a heat engine that uses high-temperature, high-pressure gas as the working fluid. Part of the heat supplied by the gas is converted directly into mechanical work. High-temperature,...

  4. Supervisory Natural Gas Analyst

    Broader source: Energy.gov [DOE]

    The Department of Energys Office of Fossil Energy, Office of Oil and Natural Gas, Office of Oil and Gas Global Security and Supply (FE) is responsible for regulating natural gas imports and exports...

  5. Fixture for forming evaporative pattern (EPC) process patterns

    DOE Patents [OSTI]

    Turner, Paul C. (Albany, OR); Jordan, Ronald R. (Albany, OR); Hansen, Jeffrey S. (Corvallis, OR)

    1993-01-01T23:59:59.000Z

    A method of casting metal using evaporative pattern casting process patterns in combination with a fixture for creating and maintaining a desired configuration in flexible patterns. A pattern is constructed and gently bent to the curvature of a suitable fixture. String or thin wire, which burns off during casting, is used to tie the pattern to the fixture. The fixture with pattern is dipped in a commercially available refractory wash to prevent metal adherence and sticking to the fixture. When the refractory wash is dry, the fixture and pattern are placed in a flask, and sand is added and compacted by vibration. The pattern remains in position, restrained by the fixture. Metal that is poured directly into the pattern replaces the pattern exactly but does not contact or weld to the fixture due to the protective refractory layer. When solid, the casting is easily separated from the fixture. The fixture can be cleaned for reuse in conventional casting cleaning equipment.

  6. Gas mixing in the wall layer of a CFB boiler

    SciTech Connect (OSTI)

    Sterneus, J.; Johnsson, F. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Energy Conversion

    1997-12-31T23:59:59.000Z

    Tracer-gas measurements were carried out in the transport zone of a 12 MW CFB boiler with special emphasis on the wall-layer flow. Helium (He) was used as tracer gas and a mass spectrometer was used to determine the He-concentrations. The primary gas velocity, U{sub 0}, was 1.2, 2.6 and 4.3 m/s (no secondary air) and the bed material was silica sand with an average particle diameter of 0.32 mm. Tracer gas was injected at different distances from one of the furnace walls and sampled above and below the injection level. In the wall layer, tracer-gas concentrations were detected above (C{sub above}) as well as below (C{sub below}) the injection height for all operating conditions, i.e., the gas flows both up and down from the injection point. The data show that the net flow of tracer gas in the wall layer depends on the operating conditions, and the concentration ratio of the down- and up-flowing gas, {psi} = C{sub below}/C{sub above}, decreases with increased gas velocity ({psi} > 1 for U{sub 0} = 1.2 m/s, {psi} {approx} 1 for U{sub 0} = 2.6 m/s and {psi} < 1 for U{sub 0} = 4.3 m/s). There exists a gas exchange between the core region and the wall-layer. A plug flow model applied to the core region gives a radial dispersion coefficient, D{sub r}, in the range of 0.015--0.025 m{sup 2}/s which is higher than the D{sub r} values reported in literature which are below 0.01 m{sup 2}/x. However, the latter values were obtained in tall and narrow risers.

  7. Method of cooling gas only nozzle fuel tip

    DOE Patents [OSTI]

    Bechtel, William Theodore (Scotia, NY); Fitts, David Orus (Ballston Spa, NY); DeLeonardo, Guy Wayne (Glenville, NY)

    2002-01-01T23:59:59.000Z

    A diffusion flame nozzle gas tip is provided to convert a dual fuel nozzle to a gas only nozzle. The nozle tip diverts compressor discharge air from the passage feeding the diffusion nozzle air swirl vanes to a region vacated by removal of the dual fuel components, so that the diverted compressor discharge air can flow to and through effusion holes in the end cap plate of the nozzle tip. In a preferred embodiment, the nozzle gas tip defines a cavity for receiving the compressor discharge air from a peripheral passage of the nozzle for flow through the effusion openings defined in the end cap plate.

  8. Natural Gas Monthly Update

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

    other liquids including biofuels and natural gas liquids. Natural Gas Exploration and reserves, storage, imports and exports, production, prices, sales. Electricity Sales, revenue...

  9. Gas Production Tax (Texas)

    Broader source: Energy.gov [DOE]

    A tax of 7.5 percent of the market value of natural gas produced in the state of Texas is imposed on every producer of gas.

  10. Historical Natural Gas Annual

    U.S. Energy Information Administration (EIA) Indexed Site

    8 The Historical Natural Gas Annual contains historical information on supply and disposition of natural gas at the national, regional, and State level as well as prices at...

  11. Natural gas dehydration apparatus

    DOE Patents [OSTI]

    Wijmans, Johannes G; Ng, Alvin; Mairal, Anurag P

    2006-11-07T23:59:59.000Z

    A process and corresponding apparatus for dehydrating gas, especially natural gas. The process includes an absorption step and a membrane pervaporation step to regenerate the liquid sorbent.

  12. Historical Natural Gas Annual

    U.S. Energy Information Administration (EIA) Indexed Site

    6 The Historical Natural Gas Annual contains historical information on supply and disposition of natural gas at the national, regional, and State level as well as prices at...

  13. Historical Natural Gas Annual

    U.S. Energy Information Administration (EIA) Indexed Site

    7 The Historical Natural Gas Annual contains historical information on supply and disposition of natural gas at the national, regional, and State level as well as prices at...

  14. SMOKE AND CFD VISUALIZATION OF THE FLOW AFTER AN EMC SCREEN IN A SUBRACK MODEL

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    SMOKE AND CFD VISUALIZATION OF THE FLOW AFTER AN EMC SCREEN IN A SUBRACK MODEL Raúl Antón1, 2, 3 analysed are the velocity, the EMC screen porosity and the subrack geometry. The technique used pattern after the screen. KEYWORDS: RNG k-, perforated plate, porosity, EMC screen, subrack, flow pattern

  15. 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.

  16. Pattern Alteration: Shoulder Slope

    E-Print Network [OSTI]

    2006-05-05T23:59:59.000Z

    Measurement Chart, for basic instructions. For additional information, refer to E-380, Shoulder Length. Square shoulders are higher than average (Fig. 1). They usually cause a garment to wrinkle and pull from the end of the shoulder toward the center front... the neck for the length of your own shoulder measurement (Fig. 7). Refer to line 8, shoulder length, on your Personal Measurement Chart. 2. Cut the pattern apart along this line, separating the armhole section from the rest of the pattern. To raise...

  17. Energy Flow Models for the Steel Industry

    E-Print Network [OSTI]

    Hyman, B.; Andersen, J. P.

    Energy patterns in the U. S. steel industry are examined using several models. First is an end-use model based on data in the 1994 Manufacturing Energy Consumption Survey (MECS). Then a seven-step process model is presented and material flow through...

  18. Layout-Aware Pattern Generation for Maximizing Supply Noise Effects on Critical Paths

    E-Print Network [OSTI]

    Tehranipoor, Mohammad

    pattern generation and validation flow is implemented on the ITC'99 b19 benchmark. Experimental results and hold times and creating clock skew. All of these effects would degrade the circuit performance

  19. A Theoretic-Experimental Model for Defining the Rate of the Air Flow through Capillary Channels*

    E-Print Network [OSTI]

    Borissova, Daniela

    authors [3, 4] recommend for gas flow formula (2), in which the mass flow and the gas pressure before cross sections. 1. Introduction The study and development of devices for generation, transformation according to the method of the electro- hydraulic analogy: (1) G P R , is a function of the pressure

  20. Apparatus and method for maintaining multi-component sample gas constituents in vapor phase during sample extraction and cooling

    DOE Patents [OSTI]

    Felix, Larry Gordon; Farthing, William Earl; Irvin, James Hodges; Snyder, Todd Robert

    2010-05-11T23:59:59.000Z

    A dilution apparatus for diluting a gas sample. The apparatus includes a sample gas conduit having a sample gas inlet end and a diluted sample gas outlet end, and a sample gas flow restricting orifice disposed proximate the sample gas inlet end connected with the sample gas conduit and providing fluid communication between the exterior and the interior of the sample gas conduit. A diluted sample gas conduit is provided within the sample gas conduit having a mixing end with a mixing space inlet opening disposed proximate the sample gas inlet end, thereby forming an annular space between the sample gas conduit and the diluted sample gas conduit. The mixing end of the diluted sample gas conduit is disposed at a distance from the sample gas flow restricting orifice. A dilution gas source connected with the sample gas inlet end of the sample gas conduit is provided for introducing a dilution gas into the annular space, and a filter is provided for filtering the sample gas. The apparatus is particularly suited for diluting heated sample gases containing one or more condensable components.

  1. Entrance effects in a developing slug flow

    E-Print Network [OSTI]

    Moissis, Raphael

    1960-01-01T23:59:59.000Z

    The kinetics of a Taylor bubble, as it rises behind a series of other bubbles in a gas-liquid slug flow, have been determined. The rise velocity of a bubble is expressed as a function of separation distance from the bubble ...

  2. Star patterns on lake ice Victor C. Tsai1,

    E-Print Network [OSTI]

    Tsai, Victor C.

    . In the process of flowing through and melting the snow, this warm water creates dark regions. The pattern so warm water-rich regions grow from a central source and evolve through a competition between thermal , biophysics 2 , condensed matter 3 , and geophysics 4 , wherein the motion of free boundaries is of central

  3. IGNITION IMPROVEMENT OF LEAN NATURAL GAS MIXTURES

    SciTech Connect (OSTI)

    Jason M. Keith

    2005-02-01T23:59:59.000Z

    This report describes work performed during a thirty month project which involves the production of dimethyl ether (DME) on-site for use as an ignition-improving additive in a compression-ignition natural gas engine. A single cylinder spark ignition engine was converted to compression ignition operation. The engine was then fully instrumented with a cylinder pressure transducer, crank shaft position sensor, airflow meter, natural gas mass flow sensor, and an exhaust temperature sensor. Finally, the engine was interfaced with a control system for pilot injection of DME. The engine testing is currently in progress. In addition, a one-pass process to form DME from natural gas was simulated with chemical processing software. Natural gas is reformed to synthesis gas (a mixture of hydrogen and carbon monoxide), converted into methanol, and finally to DME in three steps. Of additional benefit to the internal combustion engine, the offgas from the pilot process can be mixed with the main natural gas charge and is expected to improve engine performance. Furthermore, a one-pass pilot facility was constructed to produce 3.7 liters/hour (0.98 gallons/hour) DME from methanol in order to characterize the effluent DME solution and determine suitability for engine use. Successful production of DME led to an economic estimate of completing a full natural gas-to-DME pilot process. Additional experimental work in constructing a synthesis gas to methanol reactor is in progress. The overall recommendation from this work is that natural gas to DME is not a suitable pathway to improved natural gas engine performance. The major reasons are difficulties in handling DME for pilot injection and the large capital costs associated with DME production from natural gas.

  4. Method for removing metal vapor from gas streams

    DOE Patents [OSTI]

    Ahluwalia, R.K.; Im, K.H.

    1996-04-02T23:59:59.000Z

    A process for cleaning an inert gas contaminated with a metallic vapor, such as cadmium, involves withdrawing gas containing the metallic contaminant from a gas atmosphere of high purity argon; passing the gas containing the metallic contaminant to a mass transfer unit having a plurality of hot gas channels separated by a plurality of coolant gas channels; cooling the contaminated gas as it flows upward through the mass transfer unit to cause contaminated gas vapor to condense on the gas channel walls; regenerating the gas channels of the mass transfer unit; and, returning the cleaned gas to the gas atmosphere of high purity argon. The condensing of the contaminant-containing vapor occurs while suppressing contaminant particulate formation, and is promoted by providing a sufficient amount of surface area in the mass transfer unit to cause the vapor to condense and relieve supersaturation buildup such that contaminant particulates are not formed. Condensation of the contaminant is prevented on supply and return lines in which the contaminant containing gas is withdrawn and returned from and to the electrorefiner and mass transfer unit by heating and insulating the supply and return lines. 13 figs.

  5. Method for removing metal vapor from gas streams

    DOE Patents [OSTI]

    Ahluwalia, R. K. (6440 Hillcrest Dr., Burr Ridge, IL 60521); Im, K. H. (925 Lehigh Cir., Naperville, IL 60565)

    1996-01-01T23:59:59.000Z

    A process for cleaning an inert gas contaminated with a metallic vapor, such as cadmium, involves withdrawing gas containing the metallic contaminant from a gas atmosphere of high purity argon; passing the gas containing the metallic contaminant to a mass transfer unit having a plurality of hot gas channels separated by a plurality of coolant gas channels; cooling the contaminated gas as it flows upward through the mass transfer unit to cause contaminated gas vapor to condense on the gas channel walls; regenerating the gas channels of the mass transfer unit; and, returning the cleaned gas to the gas atmosphere of high purity argon. The condensing of the contaminant-containing vapor occurs while suppressing contaminant particulate formation, and is promoted by providing a sufficient amount of surface area in the mass transfer unit to cause the vapor to condense and relieve supersaturation buildup such that contaminant particulates are not formed. Condensation of the contaminant is prevented on supply and return lines in which the contaminant containing gas is withdrawn and returned from and to the electrorefiner and mass transfer unit by heating and insulating the supply and return lines.

  6. Method for eliminating gas blocking in electrokinetic pumping systems

    DOE Patents [OSTI]

    Arnold, Don W. (Livermore, CA); Paul, Phillip H. (Livermore, CA); Schoeniger, Joseph S. (Oakland, CA)

    2001-09-11T23:59:59.000Z

    A method for eliminating gas bubble blockage of current flow during operation of an electrokinetic pump. By making use of the ability to modify the surface charge on the porous dielectric medium used in electrokinetic pumps, it becomes possible to place electrodes away from the pressurized region of the electrokinetic pump. While gas is still generated at the electrodes they are situated such that the generated gas can escape into a larger buffer reservoir and not into the high pressure region of the pump where the gas bubbles can interrupt current flow. Various combinations of porous dielectric materials and ionic conductors can be used to create pumps that have desirable electrical, material handling, and flow attributes.

  7. Apparatus and method to inject a reductant into an exhaust gas feedstream

    SciTech Connect (OSTI)

    Viola, Michael B. (Macomb Township, MI)

    2009-09-22T23:59:59.000Z

    An exhaust aftertreatment system for an internal combustion engine is provided including an apparatus and method to inject a reductant into the exhaust gas feedstream. Included is a fuel metering device adapted to inject reductant into the exhaust gas feedstream and a controllable pressure regulating device. A control module is operatively connected to the reductant metering device and the controllable pressure regulating device, and, adapted to effect flow of reductant into the exhaust gas feedstream over a controllable flow range.

  8. Analysis Patterns for Oil Refineries

    E-Print Network [OSTI]

    Lei Zhen; Guangzhen Shao

    We present analysis patterns to describe the structure of oil refineries. The Refinery Produc tion Unit Pattern describes the structure of units and unit groups. The Oil Storage Pattern describes the structure of tanks and tank groups. The Oil Delivery Pattern describes the structure of stations for import and export of oil. The Production Process Pattern describes the productionprocess. The audience for this paper includes analysts, designers, and programmers who are involved in developing Refinery Information Systems.

  9. Device for precision measurement of speed of sound in a gas

    DOE Patents [OSTI]

    Kelner, Eric; Minachi, Ali; Owen, Thomas E.; Burzynski, Jr., Marion; Petullo, Steven P.

    2004-11-30T23:59:59.000Z

    A sensor for measuring the speed of sound in a gas. The sensor has a helical coil, through which the gas flows before entering an inner chamber. Flow through the coil brings the gas into thermal equilibrium with the test chamber body. After the gas enters the chamber, a transducer produces an ultrasonic pulse, which is reflected from each of two faces of a target. The time difference between the two reflected signals is used to determine the speed of sound in the gas.

  10. The effect of distributors on two-phase and three-phase flows in vertical columns

    E-Print Network [OSTI]

    Ouyang, Chie-Jan Paul

    1982-01-01T23:59:59.000Z

    been investigated in a 15. 2-centimeter internal diameter vertical column. Pressure drop across the dis- tributor and average phase hold-up were measured for two- phase and three-phase flows over flow ranges of' superficial gas velocity, 0 ? 25. 9... cm. /sec. and superficial liquid velocity, 0 ? 3. 46 cm. /sec. . Gas hold-up / pressure drop ratios were plotted against superficial gas velocity and liquid flow rate. From these plots it was found that the bubble cap was better at gas...

  11. 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

  12. Oil and Gas CDT Predicting fault permeability at depth: incorporating natural

    E-Print Network [OSTI]

    Henderson, Gideon

    Oil and Gas CDT Predicting fault permeability at depth: incorporating natural permeability controls on fluid flow in oil and gas reservoirs. Fault zones are composed of many deformation elements will receive 20 weeks bespoke, residential training of broad relevance to the oil and gas industry: 10 weeks

  13. Wireless sensor networks for off-shore oil and gas installations

    E-Print Network [OSTI]

    Gjessing, Stein

    1 Wireless sensor networks for off-shore oil and gas installations Martin Dalbro, Erik Eikeland ­ Underwater development and production of oil and gas needs networked sensors and actuators to monitor the production process, to either prevent or detect oil and gas leakage or to enhance the production flow

  14. 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

  15. Contributed papers Study of gas-fluidization dynamics with laser-polarized 129

    E-Print Network [OSTI]

    Walsworth, Ronald L.

    Gas fluidization is a process in which solid particles experience fluid-like suspension in an upward. Bubbles, or void spaces with volume much larger than that of a single particle, emerge when the gas flowContributed papers Study of gas-fluidization dynamics with laser-polarized 129 Xe Ruopeng Wanga

  16. Control structure design for stabilizing unstable gas-lift oil wells

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Control structure design for stabilizing unstable gas-lift oil wells Esmaeil Jahanshahi, Sigurd valve is the recommended solution to prevent casing-heading instability in gas-lifted oil wells. Focus to be effective to stabilize this system. Keywords: Oil production, two-phase flow, gas-lift, controllability, H

  17. SIAM J. on Applied Mathematics, submitted 20 February 1996 The Gaussian Moment Closure for Gas Dynamics

    E-Print Network [OSTI]

    Soatto, Stefano

    of extremely low pressure rarefied gas flows is important in a wide range of applications, from the reentrySIAM J. on Applied Mathematics, submitted 20 February 1996 The Gaussian Moment Closure for Gas of Levermore applied to the Boltzmann equation for rarefied gas dynamics leads to a hierarchy of symmetric

  18. Development of a new type shock tube without a diaphragm for gas-dynamic laser research

    E-Print Network [OSTI]

    Boyer, Edmond

    tube are shown in Fig.2. The cylinder sections C and D are filled with a higher pressure gas than A to the left side, and this makes the high pressure gas in the driver section flowing into the driven sectionDevelopment of a new type shock tube without a diaphragm for gas-dynamic laser research S.Kugimiya1

  19. Selection of Controlled Variables for a Natural Gas to Liquids Process Mehdi Panahi and Sigurd Skogestad*

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Selection of Controlled Variables for a Natural Gas to Liquids Process Mehdi Panahi and Sigurd variables (CVs) for a natural gas to hydrocarbon liquids (GTL) process based on the idea of self of operation are studied. In mode I, where the natural gas flow rate is given, there are three unconstrained

  20. FRICTION FACTOR IN HIGH PRESSURE NATURAL GAS PIPELINES FROM ROUGHNESS MEASUREMENTS

    E-Print Network [OSTI]

    Gudmundsson, Jon Steinar

    FRICTION FACTOR IN HIGH PRESSURE NATURAL GAS PIPELINES FROM ROUGHNESS MEASUREMENTS DETERMINATION DU and Technology, Norway ABSTRACT Pressure drop experiments on natural gas flow at 80 to 120 bar pressure and high of natural gas at typical operating pressures (100-180 bar). At such Reynolds numbers the classical Colebrook

  1. Method for improved gas-solids separation

    DOE Patents [OSTI]

    Kusik, Charles L. (Lincoln, MA); He, Bo X. (Newton, MA)

    1990-01-01T23:59:59.000Z

    Methods are disclosed for the removal of particulate solids from a gas stream at high separation efficiency, including the removal of submicron size particles. The apparatus includes a cyclone separator type of device which contains an axially mounted perforated cylindrical hollow rotor. The rotor is rotated at high velocity in the same direction as the flow of an input particle-laden gas stream to thereby cause enhanced separation of particulate matter from the gas stream in the cylindrical annular space between the rotor and the sidewall of the cyclone vessel. Substantially particle-free gas passes through the perforated surface of the spinning rotor and into the hollow rotor, from when it is discharged out of the top of the apparatus. Separated particulates are removed from the bottom of the vessel.

  2. Revamping AK-Ashland gas cleaning system

    SciTech Connect (OSTI)

    Brandes, H.; Koerbel, R. [Mannesmann Demag Corp., Coraopolis, PA (United States); Haberkamp, K. [Mannesmann Demag Huttentechnik, Duisburg (Germany); Keeton, S. [AK Steel Corp., Ashland, KY (United States)

    1995-07-01T23:59:59.000Z

    AK Steel`s (formerly Armco) BOF shop was using a static precipitator for the primary collection. The system was designed for full combustion in the gas collecting hoods. No secondary dust collection was in place. A detailed study on alternative solutions led to a completely different system in 1990, and an order was awarded to Mannesmann Demag Corp. (MDC) in Dec. 1990. The new gas collection system is using suppressed combustion with the capability to collect Co at a later stage. The gas cleaning uses the Mannesmann Demag Baumco scrubber with a venturi throat for gas flow control. All auxiliary components, water treatment plant, electric substations and sludge handling were designed and supplied by MDC. The secondary dust collection covers the hot metal and scrap charging into the BOF`s, reladling, desulfurization and deslagging by a pulse jet baghouse. All emission limits set by the EPA and guaranteed by MDC have been met by the systems installed.

  3. Method for improved gas-solids separation

    DOE Patents [OSTI]

    Kusik, C.L.; He, B.X.

    1990-11-13T23:59:59.000Z

    Methods are disclosed for the removal of particulate solids from a gas stream at high separation efficiency, including the removal of submicron size particles. The apparatus includes a cyclone separator type of device which contains an axially mounted perforated cylindrical hollow rotor. The rotor is rotated at high velocity in the same direction as the flow of an input particle-laden gas stream to thereby cause enhanced separation of particulate matter from the gas stream in the cylindrical annular space between the rotor and the sidewall of the cyclone vessel. Substantially particle-free gas passes through the perforated surface of the spinning rotor and into the hollow rotor, from where it is discharged out of the top of the apparatus. Separated particulates are removed from the bottom of the vessel. 4 figs.

  4. Estimated Water Flows in 2005: United States

    SciTech Connect (OSTI)

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

    2011-03-16T23:59:59.000Z

    Flow charts depicting water use in the United States have been constructed from publicly available data and estimates of water use patterns. Approximately 410,500 million gallons per day of water are managed throughout the United States for use in farming, power production, residential, commercial, and industrial applications. Water is obtained from four major resource classes: fresh surface-water, saline (ocean) surface-water, fresh groundwater and saline (brackish) groundwater. Water that is not consumed or evaporated during its use is returned to surface bodies of water. The flow patterns are represented in a compact 'visual atlas' of 52 state-level (all 50 states in addition to Puerto Rico and the Virgin Islands) and one national water flow chart representing a comprehensive systems view of national water resources, use, and disposition.

  5. Process and apparatus for separation of components of a gas stream

    SciTech Connect (OSTI)

    Bryan, Charles R.; Torczynski, John R.; Brady, Patrick V.; Gallis, Michail; Brooks, Carlton F.

    2014-06-17T23:59:59.000Z

    A process and apparatus for separating a gas mixture comprising providing a slot in a gas separation channel (conceptualized as a laterally elongated Clusius-Dickel column), having a length through which a net cross-flow of the gas mixture may be established; applying a higher temperature to one side of the channel and a lower temperature on an opposite side of the channel thereby causing thermal-diffusion and buoyant-convection flow to occur in the slot; and establishing a net cross-flow of a gas mixture comprising at least one higher density gas component and at least one lower density gas component along the length of the slot, wherein the cross-flow causes, in combination with the convection flow, a spiraling flow in the slot; and wherein the spiral flow causes an increasing amount of separation of the higher density gas from the lower density gas along the length of the channel. The process may use one or more slots and/or channels.

  6. Process and apparatus for separation of components of a gas stream

    SciTech Connect (OSTI)

    Bryan, Charles R; Torczynski, John R; Brady, Patrick V; Gallis, Michail; Brooks, Carlton F

    2013-11-19T23:59:59.000Z

    A process and apparatus for separating a gas mixture comprising providing a slot in a gas separation channel (conceptualized as a laterally elongated Clusius-Dickel column), having a length through which a net cross-flow of the gas mixture may be established; applying a higher temperature to one side of the channel and a lower temperature on an opposite side of the channel thereby causing thermal-diffusion and buoyant-convection flow to occur in the slot; and establishing a net cross-flow of a gas mixture comprising at least one higher density gas component and at least one lower density gas component along the length of the slot, wherein the cross-flow causes, in combination with the convection flow, a spiraling flow in the slot; and wherein the spiral flow causes an increasing amount of separation of the higher density gas from the lower density gas along the length of the channel. The process may use one or more slots and/or channels.

  7. Process and apparatus for separation of components of a gas stream

    SciTech Connect (OSTI)

    Bryan, Charles R; Torczynski, John R; Brady, Patrick V; Gallis, Michail; Brooks, Carlton F

    2013-09-17T23:59:59.000Z

    A process and apparatus for separating a gas mixture comprising providing a slot in a gas separation channel (conceptualized as a laterally elongated Clusius-Dickel column), having a length through which a net cross-flow of the gas mixture may be established; applying a higher temperature to one side of the channel and a lower temperature on an opposite side of the channel thereby causing thermal-diffusion and buoyant-convection flow to occur in the slot; and establishing a net cross-flow of a gas mixture comprising at least one higher density gas component and at least one lower density gas component along the length of the slot, wherein the cross-flow causes, in combination with the convection flow, a spiraling flow in the slot; and wherein the spiral flow causes an increasing amount of separation of the higher density gas from the lower density gas along the length of the channel. The process may use one or more slots and/or channels.

  8. Gas futures can help independents manage their risks

    SciTech Connect (OSTI)

    Treat, J.E.; Rogers, M.C. (Booz-Allen and Hamilton Inc., San Francisco, CA (US))

    1990-10-22T23:59:59.000Z

    The advent of natural gas futures trading presents the natural gas industry with a powerful tool and a formidable challenge. On the one hand, producers, pipelines, local distribution companies (LDCs), end-users, and marketers can use gas futures to hedge against price risk, protecting companies against abnormal price spikes, stabilizing cash flows, enabling companies to write long-term contracts, and facilitating planning. Gas futures can also be used in combination with oil futures to hedge against fuel switching. On the other hand, the introduction of natural gas futures trading will dramatically reshape the natural gas business. Natural gas companies from smaller independent producers to large end-users will be forced to adapt. Short-term price volatility will tend to increase. At the same time, long-term price volatility should decline. Information flows will increase. Oil and gas prices may become more closely linked. Futures prices will become benchmarks for formula-priced contracts. Increased longer-term and mid-month contracting will reduce the current reliance on month-end spot market contracts. And new players will enter the natural gas business. As a result of these trends, natural gas companies will need to adopt new strategies, systems, and organizational structures in order to remain competitive.

  9. Transportation and Greenhouse Gas Mitigation

    E-Print Network [OSTI]

    Lutsey, Nicholas P.; Sperling, Dan

    2008-01-01T23:59:59.000Z

    fuels (eg diesel, compressed natural gas). Electricity (infossil fuels, such as compressed natural gas and liquefied

  10. Controlling two-phase flow through pipe junctions

    E-Print Network [OSTI]

    Thonsgaard, Jonathan Eric

    1989-01-01T23:59:59.000Z

    industry with a study of gas networks that contain liquid condensate. His study was based on horizontal tees and gas flows with only a small liquid flow, which is considered a high quality mixture. He showed that when only a small fraction of gas enters... consisted of the same size pipe, so a direct comparison of this study's results to those of Hong was possible. Since the tee shown in Figure 6 was not constructed with a perfect fit, the three-way valve, shown in Figure 10, was used for some...

  11. Compressed gas manifold

    DOE Patents [OSTI]

    Hildebrand, Richard J. (Edgemere, MD); Wozniak, John J. (Columbia, MD)

    2001-01-01T23:59:59.000Z

    A compressed gas storage cell interconnecting manifold including a thermally activated pressure relief device, a manual safety shut-off valve, and a port for connecting the compressed gas storage cells to a motor vehicle power source and to a refueling adapter. The manifold is mechanically and pneumatically connected to a compressed gas storage cell by a bolt including a gas passage therein.

  12. Noble gas magnetic resonator

    DOE Patents [OSTI]

    Walker, Thad Gilbert; Lancor, Brian Robert; Wyllie, Robert

    2014-04-15T23:59:59.000Z

    Precise measurements of a precessional rate of noble gas in a magnetic field is obtained by constraining the time averaged direction of the spins of a stimulating alkali gas to lie in a plane transverse to the magnetic field. In this way, the magnetic field of the alkali gas does not provide a net contribution to the precessional rate of the noble gas.

  13. OIL & GAS INSTITUTE Introduction

    E-Print Network [OSTI]

    Mottram, Nigel

    OIL & GAS INSTITUTE CONTENTS Introduction Asset Integrity Underpinning Capabilities 2 4 4 6 8 9 10 COMPETITIVENESS UNIVERSITY of STRATHCLYDE OIL & GAS INSTITUTE OIL & GAS EXPERTISE AND PARTNERSHIPS #12;1 The launch of the Strathclyde Oil & Gas Institute represents an important step forward for the University

  14. Lattice gas simulations of replicating domains

    SciTech Connect (OSTI)

    Dawson, S.P.; Hasslacher, B.; Pearson, J.E.

    1993-12-31T23:59:59.000Z

    We use the lattice gas cellular automation (LGCA) developed to simulate a process of pattern-formation recently observed in reaction-diffusion systems. We study the reaction mechanism, which is an extension of the Selkov model for glycolytic oscillations. We are able to reproduce the self-replicating domains observed in this work. We use the LGCA simulation to estimate the smallest length-scale on which this process can occur under conditions encountered in the cell. These estimates are similar to those obtained for Turing patterns in the same setting.

  15. Gas gain and energy resolution of MSGCs

    SciTech Connect (OSTI)

    Neis, E.

    1995-04-01T23:59:59.000Z

    Microstrip Gas Chambers on substrates of polyimide and silicon have been built and tested with different gases and at different rates. The pattern of electrodes have a pitch ranging between 200 and 1000 microns. The width of the cathodes has also been varied. The 50 micron thick substrates of polyimide have been glued to a printed circuit board with a pattern of pick up electrodes. The signals induced on these electrodes have also been recorded and compared to the one detected by the anodes. Results of these tests will be presented and discussed.

  16. Recent X-ray Observations and the Evolution of Hot Gas in Elliptical Galaxies: Evidence for Circumgalactic Gas

    E-Print Network [OSTI]

    Fabrizio Brighenti; William G. Mathews

    1997-10-18T23:59:59.000Z

    X-ray emitting gaseous halos, such as that in elliptical galaxies like NGC 4472, cannot have been produced solely from gas expelled from galactic stars. In traditional models for the evolution of hot interstellar gas (cooling flows) in ellipticals, the galaxies are assumed to have been cleared of gas by SNII-driven winds at some early time then gas is subsequently replenished by mass loss from an evolving population of old stars. To test this, we accurately determine the stellar and dark halo mass of NGC 4472 using hydrostatic equilibrium, then solve the standard time-dependent cooling flow equations to recover the observed hot gas temperature and density distributions when evolved to the present time. This procedure fails: the computed gas density gradient is too steep, the total gas mass is too low, and the gas temperatures are much too low. All variants on this basic procedure also fail: increasing the SNIa rate, using the mass dropout assumption, arbitrarily adjusting uncertain coefficients, etc. However, agreement is achieved if the galaxy is supplied with additional, spatially-extended hot gas early in its evolution. This old ``circumgalactic'' gas can be retained to the present time and may be related to cosmological ``secondary infall''.

  17. Natural gas monthly

    SciTech Connect (OSTI)

    NONE

    1998-01-01T23:59:59.000Z

    The Natural Gas Monthly highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the Natural Gas Monthly features articles designed to assist readers in using and interpreting natural gas information.

  18. Gas turbine topping combustor

    DOE Patents [OSTI]

    Beer, J.; Dowdy, T.E.; Bachovchin, D.M.

    1997-06-10T23:59:59.000Z

    A combustor is described for burning a mixture of fuel and air in a rich combustion zone, in which the fuel bound nitrogen in converted to molecular nitrogen. The fuel rich combustion is followed by lean combustion. The products of combustion from the lean combustion are rapidly quenched so as to convert the fuel bound nitrogen to molecular nitrogen without forming NOx. The combustor has an air radial swirler that directs the air radially inward while swirling it in the circumferential direction and a radial fuel swirler that directs the fuel radially outward while swirling it in the same circumferential direction, thereby promoting vigorous mixing of the fuel and air. The air inlet has a variable flow area that is responsive to variations in the heating value of the fuel, which may be a coal-derived fuel gas. A diverging passage in the combustor in front of a bluff body causes the fuel/air mixture to recirculate with the rich combustion zone. 14 figs.

  19. 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.

  20. Design of Pattern Matching Systems: Pattern, Algorithm, and Scanner

    E-Print Network [OSTI]

    Wang, Hao

    2013-10-23T23:59:59.000Z

    Pattern matching is at the core of many computational problems, e.g., search engine, data mining, network security and information retrieval. In this dissertation, we target at the more complex patterns of regular expression and time series...