Sample records for variable pressure cavitation

  1. Using cavitation to measure statistics of low-pressure events in large-Reynolds-number turbulence

    E-Print Network [OSTI]

    La Porta, Arthur

    Using cavitation to measure statistics of low-pressure events in large-Reynolds-number turbulence A is studied using cavitation. The flow is seeded with microscopic gas bubbles and the hydrostatic pressure is reduced until large negative pressure fluctuations trigger cavitation. Cavitation is detected via light

  2. APPLICATION OF BUTTERFLY VALVES FOR FREE DISCHARGE, MINIMUM PRESSURE DROP, AND FOR CHOKING CAVITATION

    E-Print Network [OSTI]

    Rahmeyer, William J.

    CAVITATION Butterfly valves are commonly used as control valves in applications where the pressure drops and the use of a butterfly valve for flashing or choking cavitation service. Free discharge typically produces high pipe velocities at moderate pressure drops, and choking cavitation typically produces high

  3. Cavitation pressure in water Eric Herbert, Sbastien Balibar, and Frdric Caupin

    E-Print Network [OSTI]

    Caupin, Frédéric

    Cavitation pressure in water Eric Herbert, Sébastien Balibar, and Frédéric Caupin Laboratoire de investigate the limiting mechanical tension negative pressure that liquid water can sustain before cavitation experiments on cavitation, we describe our method which consists in focusing a high amplitude sound wave

  4. Cavitation pressure in water Eric Herbert, Sebastien Balibar and Frederic Caupin

    E-Print Network [OSTI]

    Balibar, Sébastien

    Cavitation pressure in water Eric Herbert, S´ebastien Balibar and Fr´ed´eric Caupin Laboratoire de mechanical tension (negative pressure) that liquid water can sustain before cavitation occurs of a postulated anomaly of its equation of state. After a brief review of previous experiments on cavitation, we

  5. ccsd-00095604,version1-18Sep2006 Understanding crack versus cavitation in pressure-sensitive

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ccsd-00095604,version1-18Sep2006 Understanding crack versus cavitation in pressure show that in addition to cavitation, interfacial cracks are encountered in a probe-tack traction test mechanisms in usual adhesives. The most common one is cavitation, as evidenced by the first tests

  6. Cavitation erosion of silver plated coating at different temperatures and pressures

    SciTech Connect (OSTI)

    Hattori, Shuji; Motoi, Yoshihiro [Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fuku-shi, Fukui 910-8507 (Japan); Kikuta, Kengo; Tomaru, Hiroshi [IHI Corperation, TOYOSU IHI BUILDING, 1-1, Toyosu 3-chome, Koto-ku, Tokyo 1358710 (Japan)

    2014-04-11T23:59:59.000Z

    Cavitation often occurs in inducer pumps used for space rockets. Silver plated coating on the inducer liner faces the damage of cavitation. Therefore, it is important to study about the cavitation erosion resistance for silver plated coating at several operating conditions in the inducer pumps. In this study, the cavitation erosion tests were carried for silver plated coating in deionized water and ethanol at several liquid temperatures (273K400K) and pressures (0.10MPa0.48MPa). The mass loss rate is evaluated in terms of thermodynamic parameter ? proposed by Brennen [9], suppression pressure pp{sub v} (p{sub v}: saturated vapor pressure) and acoustic impedance ?c (?: density and c: sound speed). Cavitation bubble behaviors depending on the thermodynamic effect and the liquid type were observed by high speed video camera. The mass loss rate is formulated by thermodynamic parameter ?, suppression pressure pp{sub v} and acoustic impedance ?c.

  7. Cavitation bubble dynamics in microfluidic gaps of variable height Pedro A. Quinto-Su, Kang Y. Lim, and Claus-Dieter Ohl

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Cavitation bubble dynamics in microfluidic gaps of variable height Pedro A. Quinto-Su, Kang Y. Lim 2009 We study experimentally the dynamics of laser-induced cavitation bubbles created inside a narrow to a semiun- bounded fluid. The cavitation bubbles are created with pulsed laser light at constant laser

  8. Carderock 2-ft Variable Pressure Cavitation Water Tunnel | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia:Power LPInformation 8thCalwind IICaneyNW1 8LHInformation

  9. Carderock 3-ft Variable Pressure Cavitation Water Tunnel | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia:Power LPInformation 8thCalwind IICaneyNW1

  10. Variable pressure thermal insulating jacket

    DOE Patents [OSTI]

    Nelson, P.A.; Malecha, R.F.; Chilenskas, A.A.

    1994-09-20T23:59:59.000Z

    A device for controlled insulation of a thermal device is disclosed. The device includes a thermal jacket with a closed volume able to be evacuated to form an insulating jacket around the thermal source. A getter material is in communication with the closed volume of the thermal jacket. The getter material can absorb and desorb a control gas to control gas pressure in the volume of the thermal jacket to control thermal conductivity in the thermal jacket. 10 figs.

  11. Variable pressure power cycle and control system

    DOE Patents [OSTI]

    Goldsberry, Fred L. (Spring, TX)

    1984-11-27T23:59:59.000Z

    A variable pressure power cycle and control system that is adjustable to a variable heat source is disclosed. The power cycle adjusts itself to the heat source so that a minimal temperature difference is maintained between the heat source fluid and the power cycle working fluid, thereby substantially matching the thermodynamic envelope of the power cycle to the thermodynamic envelope of the heat source. Adjustments are made by sensing the inlet temperature of the heat source fluid and then setting a superheated vapor temperature and pressure to achieve a minimum temperature difference between the heat source fluid and the working fluid.

  12. Small Gas Bubble Experiment for Mitigation of Cavitation Damage and Pressure Waves in Short-pulse Mercury Spallation Targets

    SciTech Connect (OSTI)

    Wendel, Mark W [ORNL] [ORNL; Felde, David K [ORNL] [ORNL; Sangrey, Robert L [ORNL] [ORNL; Abdou, Ashraf A [ORNL] [ORNL; West, David L [ORNL] [ORNL; Shea, Thomas J [ORNL] [ORNL; Hasegawa, Shoichi [Japan Atomic Energy Agency (JAEA)] [Japan Atomic Energy Agency (JAEA); Kogawa, Hiroyuki [Japan Atomic Energy Agency (JAEA)] [Japan Atomic Energy Agency (JAEA); Naoe, Dr. Takashi [Japan Atomic Energy Agency (JAEA)] [Japan Atomic Energy Agency (JAEA); Farny, Dr. Caleb H. [Boston University] [Boston University; Kaminsky, Andrew L [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    Populations of small helium gas bubbles were introduced into a flowing mercury experiment test loop to evaluate mitigation of beam-pulse induced cavitation damage and pressure waves. The test loop was developed and thoroughly tested at the Spallation Neutron Source (SNS) prior to irradiations at the Los Alamos Neutron Science Center - Weapons Neutron Research Center (LANSCE-WNR) facility. Twelve candidate bubblers were evaluated over a range of mercury flow and gas injection rates by use of a novel optical measurement technique that accurately assessed the generated bubble size distributions. Final selection for irradiation testing included two variations of a swirl bubbler provided by Japan Proton Accelerator Research Complex (J-PARC) collaborators and one orifice bubbler developed at SNS. Bubble populations of interest consisted of sizes up to 150 m in radius with achieved gas void fractions in the 10^-5 to 10^-4 range. The nominal WNR beam pulse used for the experiment created energy deposition in the mercury comparable to SNS pulses operating at 2.5 MW. Nineteen test conditions were completed each with 100 pulses, including variations on mercury flow, gas injection and protons per pulse. The principal measure of cavitation damage mitigation was surface damage assessment on test specimens that were manually replaced for each test condition. Damage assessment was done after radiation decay and decontamination by optical and laser profiling microscopy with damaged area fraction and maximum pit depth being the more valued results. Damage was reduced by flow alone; the best mitigation from bubble injection was between half and a quarter that of flow alone. Other data collected included surface motion tracking by three laser Doppler vibrometers (LDV), loop wall dynamic strain, beam diagnostics for charge and beam profile assessment, embedded hydrophones and pressure sensors, and sound measurement by a suite of conventional and contact microphones.

  13. Membrane disruption by optically controlled microbubble cavitation

    E-Print Network [OSTI]

    Loss, Daniel

    LETTERS Membrane disruption by optically controlled microbubble cavitation PAUL PRENTICE1 , ALFRED October 2005; doi:10.1038/nphys148 I n fluids, pressure-driven cavitation bubbles have a nonlinear underpinning phenomena such as sonoluminescence1 and plasma formation2 . If cavitation occurs near a rigid

  14. Minimum pressure envelope cavitation analysis using two-dimensional panel method

    E-Print Network [OSTI]

    Peterson, Christopher J., S.M. Massachusetts Institute of Technology

    2008-01-01T23:59:59.000Z

    An analysis tool for calculating minimum pressure envelopes was developed using XFOIL. This thesis presents MATLAB executables that interface with a modified version of XFOIL for determining the minimum pressure of a foil ...

  15. Understanding crack versus cavitation in pressure-sensitive adhesives: the role of kinetics

    E-Print Network [OSTI]

    Jrmie Teisseire; F. Nallet; P. Fabre; Cyprien Gay

    2006-09-18T23:59:59.000Z

    We perform traction experiments on viscous liquids highly confined between parallel plates, a geometry known as the probe-tack test in the adhesion community. Direct observation during the experiment coupled to force measurement shows the existence of several mechanisms for releasing the stress. Bubble nucleation and instantaneous growth had been observed in a previous work. Upon increasing further the traction velocity or the viscosity, the bubble growth is progressively delayed. At high velocities, cracks at the interface between the plate and the liquid appear before the bubbles have grown to their full size. Bubbles and cracks are thus observed concomitantly. At even higher velocities, cracks develop fully so early that the bubbles are not even visible. We present a theoretical model that describes these regimes, using a Maxwell fluid as a model for the actual fluid, a highly viscous silicon oil. We present the resulting phase diagramme for the different force peak regimes. The predictions are compatible with the data. Our results show that in addition to cavitation, interfacial cracks are encountered in a probe-tack traction test with viscoelastic, \\emph{liquid} materials and not solely with viscoelastic solids like adhesives.

  16. Heterogeneous cavitation in liquid helium 4 near a glass plate

    E-Print Network [OSTI]

    Caupin, Frédéric

    Heterogeneous cavitation in liquid helium 4 near a glass plate X. Chavanne, S. Balibar and F wave to study cavitation, i.e. the nucleation of bubbles, in liquid helium 4 near a clean glass plate and threshold pressures in the range 0 to -3 bar, significantly less negative than for homogeneous cavitation

  17. d Original Contribution IDENTIFYING THE INERTIAL CAVITATION THRESHOLD AND SKULL

    E-Print Network [OSTI]

    Konofagou, Elisa E.

    d Original Contribution IDENTIFYING THE INERTIAL CAVITATION THRESHOLD AND SKULL EFFECTS IN AVESSEL unknown. To investigate the pressure threshold for inertial cavitation of pre- formed microbubbles during sonication, passive cavitation detection in conjunction with B-mode imaging was used. A cerebral vessel

  18. WATER TRANSPORT IN VESSELLESS ANGIOSPERMS: CONDUCTING EFFICIENCY AND CAVITATION SAFETY

    E-Print Network [OSTI]

    Hacke, Uwe

    WATER TRANSPORT IN VESSELLESS ANGIOSPERMS: CONDUCTING EFFICIENCY AND CAVITATION SAFETY U. G. Hacke. Second, vesselless wood ought to be exceptionally safe from cavitation if the small cumulative area woods averaged a cavitation pressure of ?3:4 6 0:3 MPa, which is low for their wet habitats

  19. Role of Cavitation in Bulk Ultrasound Ablation: A Histologic Study

    E-Print Network [OSTI]

    Mast, T. Douglas

    Role of Cavitation in Bulk Ultrasound Ablation: A Histologic Study Chandra Priya Karunakaran, Mark of Cincinnati, Cincinnati, Ohio Abstract. The role of cavitation in bulk ultrasound ablation has been evaluated-ablate probe at 31 W/cm2 for 20 minutes under normal and elevated ambient pressures. A 1 MHz passive cavitation

  20. Multi-variable optimization of pressurized oxy-coal combustion

    E-Print Network [OSTI]

    Zebian, Hussam

    2011-01-01T23:59:59.000Z

    Simultaneous multi-variable gradient-based optimization with multi-start is performed on a 300 MWe wet-recycling pressurized oxy-coal combustion process with carbon capture and sequestration. The model accounts for realistic ...

  1. A theoretical analysis of rotating cavitation in inducers

    SciTech Connect (OSTI)

    Tsujimoto, Y.; Kamijo, K. (National Aerospace Lab., Miyagi, (Japan)); Yoshida, Y. (Osaka Univ., Toyonaka, (Japan). Engineering Science)

    1993-03-01T23:59:59.000Z

    Rotating cavitation was analyzed using an actuator disk method. Quasi-steady pressure performance of the impeller, mass flow gain factor, and cavitation compliance of the cavity were taken into account. Three types of destabilizing modes were predicted: rotation cavitation propagating faster than the rotational speed of the impeller, rotating cavitation propagating in the direction opposite that of the impeller, and rotating stall propagating slower than the rotational speed of the impeller. It was shown that both types of rotating cavitation were caused by the positive mass flow gain factor, while the rotating stall was caused by the positive slope of the pressure performance. Stability and propagation velocity maps are presented for the two types of rotating cavitation in the mass flow gain factor-cavitation compliance place. The correlation between theoretical results and experimental observations is discussed.

  2. Quantum Cavitation

    E-Print Network [OSTI]

    Paola Zizzi; Eliano Pessa; Fabio Cardone

    2010-06-05T23:59:59.000Z

    We consider the theoretical setting of a superfluid like 3He in a rotating container, which is set between the two layers of a type-II superconductor. We describe the superfluid vortices as a 2-dimensional Ising-like model on a triangular lattice in presence of local magnetic fields. The interaction term of the superfluid vortices with the Abrikosov vortices of the superconductor appears then as a symmetry breaking term in the free energy. Such a term gives a higher probability of quantum tunnelling across the potential barrier for bubbles nucleation, thus favouring quantum cavitation.

  3. New Insights into the Mechanisms of Water-Stress-Induced Cavitation in Conifers

    E-Print Network [OSTI]

    Mencuccini, Maurizio

    New Insights into the Mechanisms of Water-Stress-Induced Cavitation in Conifers Herve´ Cochard of Edinburgh, Edinburgh EH9 3JN, United Kingdom (M.M.) Cavitation resistance is a key parameter to understand at a pressure sufficient to aspirate pit tori and well above the pressure for cavitation induction we failed

  4. Megasonic cleaning of wafers in electrolyte solutions: Possible role of electro-acoustic and cavitation effects

    E-Print Network [OSTI]

    Deymier, Pierre

    -acoustic and cavitation effects M. Keswani a , S. Raghavan a,*, P. Deymier a , S. Verhaverbeke b a Materials Science Keywords: Wafer Cleaning Electrolyte Megasonic Electro-acoustic Cavitation Pressure amplitude a b s t r a c Waals adhesion forces. The effect of ionic strength on cavitation has been investigated through

  5. Effect of Nuclei Concentration on Cavitation Cluster Dynamics C.D. Ohl, and D. Lohse

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Effect of Nuclei Concentration on Cavitation Cluster Dynamics M. Arora, C.D. Ohl, and D. Lohse, The Netherlands. (Dated: July 2, 2007) 1 #12;Abstract Cavitation cluster dynamics after the passage of a single pressure wave is studied for different concentrations of artificial cavitation nuclei (30 to 3·105 nuclei

  6. Simulating Cavitation and Hydraulic Flip Inside Hydroentangling Nozzles H. VAHEDI TAFRESHI AND B. POURDEYHIMI

    E-Print Network [OSTI]

    Tafreshi, Hooman Vahedi

    Simulating Cavitation and Hydraulic Flip Inside Hydroentangling Nozzles H. VAHEDI TAFRESHI AND B at high pressures. Recent studies have shown that cavitation severely affects the integrity of high-state simulation, which shows the inception and time-evolution of a cavitation cloud inside a hydroentan- gling

  7. FLUID-STRUCTURE INTERACTION AND TRANSIENT CAVITATION TESTS IN A T-PIECE PIPE

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    FLUID-STRUCTURE INTERACTION AND TRANSIENT CAVITATION TESTS IN A T-PIECE PIPE ARRIS S TIJSSELING featuring the combined phenomena of fluid-structure interaction (FSI) and vaporous cavitation is presented and the static pressure of the liquid control the severity of the cavitation phenomenon. Keywords: Water hammer

  8. American Journal of Botany 87(9): 12871299. 2000. VULNERABILITY TO XYLEM CAVITATION AND THE

    E-Print Network [OSTI]

    Pockman, William T.

    1287 American Journal of Botany 87(9): 1287­1299. 2000. VULNERABILITY TO XYLEM CAVITATION to evaluate how the limitation of xylem pressure ( x) by cavitation corresponded with plant distribution along xylem, which shows the decrease in hydraulic conductance from cavitation as a function of x and the crit

  9. Cavitation effects on the confinement/deconfinement transition

    E-Print Network [OSTI]

    Alex Buchel; Xian O. Camanho; Jose D. Edelstein

    2014-05-23T23:59:59.000Z

    Cavitation is a process where the viscous terms in a relativistic fluid result in reducing the effective pressure, thus facilitating the nucleation of bubbles of a stable phase. The effect is particularly pronounced in the vicinity of a (weak) first-order phase transition. We use the holographic correspondence to study cavitation in a strongly coupled planar cascading gauge theory plasma close to the confinement/deconfinement phase transition. While in this particular model the shift of the deconfinement temperature due to cavitation does not exceed 5%, we speculate that cavitation might be important near the QCD critical point.

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

    E-Print Network [OSTI]

    Chen, Y.; Zhang, Z.

    2006-01-01T23:59:59.000Z

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

  11. Cavitation Density of Superfluid Helium-4 around 1 K

    E-Print Network [OSTI]

    An Qu; Azer Trimeche; Jacques Dupont-roc; Jules Grucker; Philippe Jacquier

    2015-04-14T23:59:59.000Z

    Using an optical interferomertric method, the homogeneous cavitation density of superfluid helium at $T=0.96\\,$K is measured and found to be $\\rho_{cav}=0.1338\\pm0.0002\\rm\\,g.cm^{-3}$. A well established equation of state for liquid helium at negative pressures converts this to the cavitation pressure $P_{cav}=-5.1\\pm0.1\\,$bar. This cavitation pressure is consistent with a model taking into account the presence of quantized vortices, but disagrees with previously published experimental values of $P_{cav}$.

  12. OPTIC CAVITATION W. Lauterborn

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    , especially ship pro- pellers, turbines, pumps and hydrofoils. This type of cavitation is called hydraulic of liquids, was Leonhard Euler as early as 1754 in his work on the theory of turbines 11 with ship propel- lers. Nowadays cavitation presents a problem in all kinds of hydraulic machinery

  13. REVIEW OF SCIENTIFIC INSTRUMENTS 82, 034904 (2011) Fiber optic probe hydrophone for the study of acoustic cavitation in water

    E-Print Network [OSTI]

    Davitt, Kristina

    of acoustic cavitation in water Arnaud Arvengas, Kristina Davitt, and Frédéric Caupina) Laboratoire de. Accord- ing to nucleation theory, increasing the ultrasound frequency increases the cavitation threshold in liquids. We are able to resolve the fractional change in the pressure threshold for cavitation in water

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

    E-Print Network [OSTI]

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

    2006-01-01T23:59:59.000Z

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

  15. Cavitation and two-phase flow characteristics of SRPR (Savannah River Plant Reactor) pump. Final report

    SciTech Connect (OSTI)

    Not Available

    1991-07-01T23:59:59.000Z

    The possible head degradation of the SRPR pumps may be attributable to two independent phenomena, one due to the inception of cavitation and the other due to the two-phase flow phenomena. The head degradation due to the appearance of cavitation on the pump blade is hardly likely in the conventional pressurized water reactor (PWR) since the coolant circulating line is highly pressurized so that the cavitation is difficult to occur even at LOCA (loss of coolant accident) conditions. On the other hand, the suction pressure of SRPR pump is order-of-magnitude smaller than that of PWR so that the cavitation phenomena, may prevail, should LOCA occur, depending on the extent of LOCA condition. In this study, therefore, both cavitation phenomena and two-phase flow phenomena were investigated for the SRPR pump by using various analytical tools and the numerical results are presented herein.

  16. Vulnerability of Xylem Vessels to Cavitation in Sugar Maple. Scaling from Individual Vessels to

    E-Print Network [OSTI]

    Melcher, Peter

    nega- tive pressures (Dixon and Joly, 1895; Briggs, 1950) allows plants to power the movement of water to withstand tension-induced cavitation is typ- ically inferred from "vulnerability curves" generatedVulnerability of Xylem Vessels to Cavitation in Sugar Maple. Scaling from Individual Vessels

  17. Resonance et contr^ole en cavite ouverte Jer^ome Hoepffner

    E-Print Network [OSTI]

    Hoepffner, Jrme

    Resonance et contr^ole en cavite ouverte Jer^ome Hoepffner KTH, Sweden Avec Espen Akervik, Uwe) From Rowley et al, JFM 2002 Self sustained cycle: perturbation growth pressure wave new perturbation localised and where are they sensitive ? #12;Optimal transient energy growth from initial conditions System

  18. TURBULENT PRESSURE IN THE ENVELOPES OF YELLOW HYPERGIANTS AND LUMINOUS BLUE VARIABLES

    E-Print Network [OSTI]

    TURBULENT PRESSURE IN THE ENVELOPES OF YELLOW HYPERGIANTS AND LUMINOUS BLUE VARIABLES Richard B turbulent pressure) affects the structure and stability of luminous post­red-supergiant stars is critically and generates energetic shocks or if convection is unable to transport all of the super-Eddington luminous flux

  19. Acoustic cavitation and its chemical consequences

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Acoustic cavitation and its chemical consequences By Kenneth S. Suslick, Yuri Didenko, Ming M. Fang Acoustic cavitation is responsible for both sonochemistry and sonoluminescence. Bubble collapse in liquids, sonochemistry and sonoluminescence derive principally from acoustic cavitation: the formation, growth

  20. CAV2001 Fourth International Symposium on Cavitation Cavitation and the state of stress

    E-Print Network [OSTI]

    Joseph, Daniel D.

    CAV2001 Fourth International Symposium on Cavitation Cavitation and the state of stress/2001/paper/Cavitation/cavupdate.tex ca Abstract The problem of the inception of cavitation is formulated in terms of a comparison of the breaking strength or cavitation threshold at each point

  1. Cavitation-resistant inducer

    DOE Patents [OSTI]

    Dunn, Charlton (Calabasas, CA); Subbaraman, Maria R. (Canoga Park, CA)

    1989-01-01T23:59:59.000Z

    An improvement in an inducer for a pump wherein the inducer includes a hub, a plurality of radially extending substantially helical blades and a wall member extending about and encompassing an outer periphery of the blades. The improvement comprises forming adjacent pairs of blades and the hub to provide a substantially rectangular cross-sectional flow area which cross-sectional flow area decreases from the inlet end of the inducer to a discharge end of the inducer, resulting in increased inducer efficiency improved suction performance, reduced susceptibility to cavitation, reduced susceptibility to hub separation and reduced fabrication costs.

  2. Cavitation-resistant inducer

    DOE Patents [OSTI]

    Dunn, C.; Subbaraman, M.R.

    1989-06-13T23:59:59.000Z

    An improvement in an inducer for a pump is disclosed wherein the inducer includes a hub, a plurality of radially extending substantially helical blades and a wall member extending about and encompassing an outer periphery of the blades. The improvement comprises forming adjacent pairs of blades and the hub to provide a substantially rectangular cross-sectional flow area which cross-sectional flow area decreases from the inlet end of the inducer to a discharge end of the inducer, resulting in increased inducer efficiency improved suction performance, reduced susceptibility to cavitation, reduced susceptibility to hub separation and reduced fabrication costs. 11 figs.

  3. A nonlinear calculation of rotating cavitation in inducers

    SciTech Connect (OSTI)

    Tsujimoto, Y. [Osaka Univ., Toyonaka, Osaka (Japan). Dept. of Mechanical Engineering]|[National Aerospace Lab., Kakuda, Miyagi (Japan); Watanabe, S.; Yoshida, Y. [Osaka Univ., Toyonaka, Osaka (Japan); Kamijo, K. [National Aerospace Lab., Kakuda, Miyagi (Japan)

    1996-09-01T23:59:59.000Z

    In the previous linear analysis (Tsujimoto et al., 1993) it was found that there can be a backward rotating cavitation as well as a forward mode which rotates faster than impeller. Although some shaft vibration has been observed, which might be caused by the backward mode, experimental evidence has been obtained only for the forward mode. The purpose of the present study is to find out the factors which determine the amplitude of each mode of rotating cavitation by taking into account several nonlinearities. A time marching nonlinear 2-D flow analysis was carried out for this purpose. It was found that the increase of cavitation compliance at lower inlet pressure can be a factor which limits the amplitude. The mode selectivity is mainly dependent on the stability limit obtained by a linear analysis for which the phase delay of cavity has a most important effect.

  4. A nonlinear calculation of rotating cavitation in inducers

    SciTech Connect (OSTI)

    Tsujimoto, Y.; Watanabe, S.; Yoshida, Y. [Osaka Univ., Osaka (Japan); Kamijo, K. [Kakuda Research Center (Japan). Rocket Propulsion Division

    1994-12-31T23:59:59.000Z

    In the previous linear analysis (Tsujimoto et al., 1993) it was found that there can be a backward rotating cavitation as well as a forward mode which rotates faster than impeller. Although some shaft vibration has been observed which might be caused by the backward mode, experimental evidence has been obtained only for the forward mode. The ultimate goal of the present study is to answer the question which mode of the cavitation instabilities -- cavitation surge and the two modes of rotating cavitation -- occurs in a given system and operating condition, and to find out analytical method to determine their amplitude. A time marching non-linear 2-D flow analysis was carried out for this purpose. It was found that the increase of cavitation compliance at lower inlet pressure can be a factor which limits the amplitude. The mode selectivity is mainly dependent on the stability limit obtained by a linear analysis for which the phase delay of cavity has a most important effect.

  5. Roles of cavitation/column separation due to earthquake-induced hydraulic transients

    SciTech Connect (OSTI)

    Hwang, Y.D.

    1986-01-01T23:59:59.000Z

    The roles of cavitation/column separation due to earthquake-induced hydraulic transients in pipe flow were investigated experimentally and theoretically. It is known that when the system pressure during a hydraulic transient reaches the saturation pressure of the liquid, cavitation/column separation occurs. When the cavities collapse or when the separated liquid columns rejoin, very high pressures are produced. The experiment employed a pipe mounted between a constant-pressure tank and a piston-type excitation device. The resulting pressure variation at the piston was recorded continually. Comparison of pressure response for various test runs indicated that the peak pressures at/near resonance frequency were not affected significantly by the excitation velocity amplitude in cases of cavitation/column separation. These results were confirmed by comparison with theoretical analysis. A numerical method to simulate column separation/cavitation was developed. In order to eliminate numerical oscillation, the flux-correction method was introduced. Results obtained suggest that the cavitation/column separation due to earthquake-induced hydraulic transients is an important damage mechanism.

  6. Numerical investigation of high-pressure combustion in rocket engines using Flamelet/Progress-variable models

    E-Print Network [OSTI]

    Coclite, A; De Palma, P; Pascazio, G

    2015-01-01T23:59:59.000Z

    The present paper deals with the numerical study of high pressure LOx/H2 or LOx/hydrocarbon combustion for propulsion systems. The present research effort is driven by the continued interest in achieving low cost, reliable access to space and more recently, by the renewed interest in hypersonic transportation systems capable of reducing time-to-destination. Moreover, combustion at high pressure has been assumed as a key issue to achieve better propulsive performance and lower environmental impact, as long as the replacement of hydrogen with a hydrocarbon, to reduce the costs related to ground operations and increase flexibility. The current work provides a model for the numerical simulation of high- pressure turbulent combustion employing detailed chemistry description, embedded in a RANS equations solver with a Low Reynolds number k-omega turbulence model. The model used to study such a combustion phenomenon is an extension of the standard flamelet-progress-variable (FPV) turbulent combustion model combined ...

  7. Cavitation Fatigue. Embolism and Refilling Cycles Can Weaken the Cavitation Resistance of Xylem1

    E-Print Network [OSTI]

    Stiller, Volker

    Cavitation Fatigue. Embolism and Refilling Cycles Can Weaken the Cavitation Resistance of Xylem1Culloh Department of Biology, University of Utah, Salt Lake City, Utah 84112 Although cavitation and refilling cycles could be common in plants, it is unknown whether these cycles weaken the cavitation resistance

  8. Cavitation in elastomeric solids: II--Onset-of-cavitation surfaces for Neo-Hookean materials

    E-Print Network [OSTI]

    Lopez-Pamies, Oscar

    Cavitation in elastomeric solids: II--Onset-of-cavitation surfaces for Neo-Hookean materials Oscar a fairly general theory of cavitation in elastomeric solids based on the sudden growth of pre-existing defects. In this article, the theory is used to determine onset-of-cavitation surfaces for Neo

  9. Cavitation in elastomeric solids: II--Onset-of-cavitation surfaces for Neo-Hookean materials

    E-Print Network [OSTI]

    Nakamura, Toshio

    Cavitation in elastomeric solids: II--Onset-of-cavitation surfaces for Neo-Hookean materials Oscar of cavitation in elastomeric solids based on the sudden growth of pre-existing defects. In this article, the theory is used to determine onset-of-cavitation surfaces for Neo-Hookean solids where the defects

  10. EXPERIMENTS AND MODELLING OF CAVITATING FLOWS IN VENTURI: ATTACHED SHEET CAVITATION

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 EXPERIMENTS AND MODELLING OF CAVITATING FLOWS IN VENTURI: ATTACHED SHEET CAVITATION S. Barre* , J and numerical studies were carried out to analyse cavitating flows and to describe the two- phase flow structures of attached sheet cavitation in Venturi geometries. New double optical probe measurements were

  11. Spatial control of cavitation in therapeutic ultrasound

    E-Print Network [OSTI]

    Gauthier, Thomas P., 1980-

    2005-01-01T23:59:59.000Z

    Inertial cavitation has been implicated as the primary mechanism for a host of emerging applications. In all these applications, the main concern is to induce cavitation in perfectly controlled locations in the field; this ...

  12. Quasiconformal Hyperelasticity Cavitation is not Allowed

    E-Print Network [OSTI]

    Kovalev, Leonid

    Quasiconformal Hyperelasticity when Cavitation is not Allowed Tadeusz Iwaniec Jani Onninen Abstract that the lower bound at (3) prevents all sorts of cavitation from growing to higher dimensions. For instance

  13. ULTRASONIC CAVITATION IN FREON AT ROOM TEMPERATURE

    E-Print Network [OSTI]

    Caupin, Frédéric

    ULTRASONIC CAVITATION IN FREON AT ROOM TEMPERATURE FR´ED´ERIC CAUPIN AND VINCENT FOURMOND on ultrasonic cavitation in freon (1,1,2-trichloro 1,2,2-trifluoro ethane). We use a high intensity 1 MHz observe the nucleation of bubbles. We describe the three different methods we use to detect cavitation

  14. Compressible fluid model for hydrodynamic lubrication cavitation

    E-Print Network [OSTI]

    Sart, Remi

    Compressible fluid model for hydrodynamic lubrication cavitation G. Bayada L. Chupin I.C.J. UMR.chupin@math.univ-bpclermont.fr Keywords: cavitation, compressible Reynolds equation Date: april 2013 Summary In this paper, it is shown how vaporous cavitation in lubricant films can be modelled in a physically justified manner through

  15. Catastrophic Cracking Courtesy of Quiescent Cavitation

    E-Print Network [OSTI]

    Daily, D Jesse; Thomson, Scott L; Truscott, Tadd T

    2012-01-01T23:59:59.000Z

    A popular party trick is to fill a glass bottle with water and hit the top of the bottle with an open hand, causing the bottom of the bottle to break open. We investigate the source of the catastrophic cracking through the use of high-speed video and an accelerometer attached to the bottom of a glass bottle. Upon closer inspection, it is obvious that the acceleration caused by hitting the top of the bottle is followed by the formation of bubbles near the bottom. The nearly instantaneous acceleration creates an area of low pressure on the bottom of the bottle where cavitation bubbles form. Moments later, the cavitation bubbles collapse at roughly 10 times the speed of formation, causing the bottle to break. The accelerometer data shows that the bottle is broken after the bubbles collapse and that the magnitude of the bubble collapse is greater than the initial impact. The fluid dynamics video highlights that this trick will not work if the bottle is empty nor if it is filled with a carbonated fluid because the...

  16. Optimized Fan Control In Variable Air Volume HVAC Systems Using Static Pressure Resets: Strategy Selection and Savings Analysis

    E-Print Network [OSTI]

    Kimla, John

    2010-07-14T23:59:59.000Z

    The potential of static pressure reset (SPR) control to save fan energy in variable air volume HVAC systems has been well documented. Current research has focused on the creation of reset strategies depending on specific system features...

  17. Onset of cavitation in the quark-gluon plasma

    E-Print Network [OSTI]

    Mathis Habich; Paul Romatschke

    2014-07-11T23:59:59.000Z

    We study the onset of bubble formation (cavitation) in the quark-gluon plasma as a result of the reduction of the effective pressure from bulk-viscous corrections. By calculating velocity gradients in typical models for quark-gluon plasma evolution in heavy-ion collisions, we obtain results for the critical bulk viscosity above which cavitation occurs. Since present experimental data for heavy-ion collisions seems inconsistent with the presence of bubbles above the phase transition temperature of QCD, our results may be interpreted as an upper limit of the bulk viscosity in nature. Our results indicate that bubble formation is consistent with the expectation of hadronisation in low-temperature QCD.

  18. Method of forming cavitated objects of controlled dimension

    DOE Patents [OSTI]

    Anderson, P.R.; Miller, W.J.

    1981-02-11T23:59:59.000Z

    A method is disclosed of controllably varying the dimensions of cavitated objects such as hollow spherical shells wherein a precursor shell is heated to a temperature above the shell softening temperature in an ambient atmosphere wherein the ratio of gases which are permeable through the shell wall at that temperature to gases which are impermeable through the shell wall is substantially greater than the corresponding ratio for gases contained within the precursor shell. As the shell expands, the partial pressures of permeable gases internally and externally of the shell approach and achieve equilibrium, so that the final shell size depends solely upon the difference in impermeable gas partial pressures and shell surface tension.

  19. Method of forming cavitated objects of controlled dimension

    DOE Patents [OSTI]

    Anderson, Paul R. (Toledo, OH); Miller, Wayne J. (Ann Arbor, MI)

    1982-01-01T23:59:59.000Z

    A method of controllably varying the dimensions of cavitated objects such as hollow spherical shells wherein a precursor shell is heated to a temperature above the shell softening temperature in an ambient atmosphere wherein the ratio of gases which are permeable through the shell wall at that temperature to gases which are impermeable through the shell wall is substantially greater than the corresponding ratio for gases contained within the precursor shell. As the shell expands, the partial pressures of permeable gases internally and externally of the shell approach and achieve equilibrium, so that the final shell size depends solely upon the difference in impermeable gas partial pressures and shell surface tension.

  20. Conceptual design of a pressure tube light water reactor with variable moderator control

    SciTech Connect (OSTI)

    Rachamin, R.; Fridman, E. [Reactor Safety Div., Inst. of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf, POB 51 01 19, 01314 Dresden (Germany); Galperin, A. [Dept. of Nuclear Engineering, Ben-Gurion Univ. of the Negev, POB 653, Beer Sheva 84105 (Israel)

    2012-07-01T23:59:59.000Z

    This paper presents the development of innovative pressure tube light water reactor with variable moderator control. The core layout is derived from a CANDU line of reactors in general, and advanced ACR-1000 design in particular. It should be stressed however, that while some of the ACR-1000 mechanical design features are adopted, the core design basics of the reactor proposed here are completely different. First, the inter fuel channels spacing, surrounded by the calandria tank, contains a low pressure gas instead of heavy water moderator. Second, the fuel channel design features an additional/external tube (designated as moderator tube) connected to a separate moderator management system. The moderator management system is design to vary the moderator tube content from 'dry' (gas) to 'flooded' (light water filled). The dynamic variation of the moderator is a unique and very important feature of the proposed design. The moderator variation allows an implementation of the 'breed and burn' mode of operation. The 'breed and burn' mode of operation is implemented by keeping the moderator tube empty ('dry' filled with gas) during the breed part of the fuel depletion and subsequently introducing the moderator by 'flooding' the moderator tube for the 'burn' part. This paper assesses the conceptual feasibility of the proposed concept from a neutronics point of view. (authors)

  1. Experimental and analytical study of rotating cavitation

    SciTech Connect (OSTI)

    Kamijo, Kenjiro; Shimura, Takashi; Tsujimoto, Yoshinobu [National Aerospace Lab., Miyagi (Japan). Kakuda Research Center

    1994-12-31T23:59:59.000Z

    This paper describes experimental and analytical results of rotating cavitation. There are four major sections in this paper. The first section presents the main characteristics of rotating cavitation which was found in the inducer test using a water tunnel. The second section describes the rotating cavitation which occurred in the development test of an LE-7 liquid oxygen pump for the H-II rocket. Also described in this section is how the rotating cavitation was suppressed. The rotating cavitation was the cause of both super synchronous shaft vibration and an unstable head coefficient curve. The third section presents how the theory of rotating cavitation was developed. The final section shows the measured cavitation compliance and mass flow gain factor of the LE-7 pump inducer for comparison of the experimental and analytical results of the rotating cavitation of the LE-7 pump inducer. Almost all the information presented in this paper has already been reported by Kamijo et al. (1977, 1980, 1993, 1993) and by Shimura (1993). In the present paper, the authors attempt to combine and give a clear overview of the experimental and analytical results described in the previous papers to systematically show their experience and findings on rotating cavitation.

  2. System for detecting operating errors in a variable valve timing engine using pressure sensors

    DOE Patents [OSTI]

    Wiles, Matthew A.; Marriot, Craig D

    2013-07-02T23:59:59.000Z

    A method and control module includes a pressure sensor data comparison module that compares measured pressure volume signal segments to ideal pressure volume segments. A valve actuation hardware remedy module performs a hardware remedy in response to comparing the measured pressure volume signal segments to the ideal pressure volume segments when a valve actuation hardware failure is detected.

  3. Pre-breakdown cavitation development in the dielectric fluid in the inhomogeneous, pulsed electric fields

    E-Print Network [OSTI]

    Mikhail N. Shneider; Mikhail Pekker

    2014-12-01T23:59:59.000Z

    We consider the development of pre-breakdown cavitation nanopores appearing in the dielectric fluid under the influence of the electrostrictive stresses in the inhomogeneous pulsed electric field. It is shown that three characteristic regions can be distinguished near the needle electrode. In the first region, where the electric field gradient is greatest, the cavitation nanopores, occurring during the voltage nanosecond pulse, may grow to the size at which an electron accelerated by the field inside the pores can acquire enough energy for excitation and ionization of the liquid on the opposite pore wall, i.e., the breakdown conditions are satisfied. In the second region, the negative pressure caused by the electrostriction is large enough for the cavitation initiation (which can be registered by optical methods), but, during the voltage pulse, the pores do not reach the size at which the potential difference across their borders becomes sufficient for ionization or excitation of water molecules. And, in the third, the development of cavitation is impossible, due to an insufficient level of the negative pressure: in this area, the spontaneously occurring micropores do not grow and collapse under the influence of surface tension forces. This paper discusses the expansion dynamics of the cavitation pores and their most probable shape.

  4. Investigation of noninertial cavitation produced by an ultrasonic horn

    E-Print Network [OSTI]

    Sóbester, András

    Investigation of noninertial cavitation produced by an ultrasonic horn Peter R. Birkin,a) Douglas G; accepted 22 September 2011) This paper reports on noninertial cavitation that occurs beyond the zone close to the horn tip to which the inertial cavitation is confined. The noninertial cavitation is characterized

  5. Cavitation in an Orifice Flow , W. A. Sirignano

    E-Print Network [OSTI]

    Joseph, Daniel D.

    Cavitation in an Orifice Flow S. Dabiri , W. A. Sirignano Department of Mechanical and Aerospace the potential locations for cavitation induced by total stress on the flow of a liquid through an orifice. The total-stress criterion for cavitation is applied to find the regions where cavitation is likely to occur

  6. Mechanical Damage from Cavitation in High Intensity Focused Ultrasound Accelerated Thrombolysis

    E-Print Network [OSTI]

    Weiss, Hope

    2012-01-01T23:59:59.000Z

    3.3 Cavitation Model . . . . . . . . . . . . . . . . . . . .Field Characterization / Passive Cavitation Detection 2.3Method for Estimation of Cavitation Damage for an Embedded

  7. Generation of laser-induced cavitation bubbles with a digital hologram

    E-Print Network [OSTI]

    Quinto-Su, P. A; Venugopalan, V.; Ohl, C.-D.

    2008-01-01T23:59:59.000Z

    C. D. Ohl, Controlled cavitation-cell interaction: trans-R. Dijkink and C. D. Ohl, Cavitation based micropump, Labobservations of laser- induced cavitation bubbles in water,

  8. A body force model for cavitating inducers in rocket engine turbopumps

    E-Print Network [OSTI]

    Sorensen, William Alarik

    2014-01-01T23:59:59.000Z

    Modern rocket engine turbopumps utilize cavitating inducers to meet mass and volume requirements. Rotating cavitation and higher order cavitation instabilities have frequently been observed during inducer testing and ...

  9. Evaluation of CAVIJET cavitating jets for deep-hole rock cutting

    SciTech Connect (OSTI)

    Conn, A.F.; Johnson, V.E. Jr.; Liu, H.L.; Frederick, G.S.

    1981-05-01T23:59:59.000Z

    A feasibility study has shown that the CAVIJET cavitating fluid jet method should be capable of successfully augmenting the cutting action of mechanical bits under deep-hole conditions. Increased rock cutting rates by existing cavitating jet nozzles can be anticipated with conventional rig pressures for hole depths of at least 1200 m (4000 ft) and possibly deeper. Improved rates of penetration, based on preliminary laboratory roller bit tests, should be achieved by simply substituting CAVIJET nozzles absorbing equivalent hydraulic power for conventional roller bit nozzles.

  10. Supplementary Methods for "Comment on 'Nuclear Emissions During Self-Nucleated Acoustic Cavitation'"

    E-Print Network [OSTI]

    B. Naranjo

    2006-09-11T23:59:59.000Z

    Neutron simulation methods and statistical fitting methods for "Comment on 'Nuclear Emissions During Self-Nucleated Acoustic Cavitation'" are presented. The fit that underlies the Comment's background-subtracted "Cf-252" curve is shown. Also included are numerically sampled distributions of the goodness-of-fit variable for the four candidate neutron sources and a sketch of the assumed geometry.

  11. Drying by Cavitation and Poroelastic Relaxations in Porous Media with Macroscopic Pores Connected by Nanoscale Throats

    E-Print Network [OSTI]

    Olivier Vincent; David A. Sessoms; Erik J. Huber; Jules Guioth; Abraham D. Stroock

    2014-09-30T23:59:59.000Z

    We investigate the drying dynamics of porous media with two pore diameters separated by several orders of magnitude. Nanometer-sized pores at the edge of our samples prevent air entry, while drying proceeds by heterogeneous nucleation of vapor bubbles (cavitation) in the liquid in micrometer-sized voids within the sample. We show that the dynamics of cavitation and drying are set by the interplay of the deterministic poroelastic mass transport in the porous medium and the stochastic nucleation process. Spatio-temporal patterns emerge in this unusual reaction-diffusion system, with temporal oscillations in the drying rate and variable roughness of the drying front.

  12. Cavitation Thermometry Using Molecular and Continuum Sonoluminescence Lawrence S. Bernstein* and Mitchell R. Zakin

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Cavitation Thermometry Using Molecular and Continuum Sonoluminescence Lawrence S. Bernstein (SB) sonoluminescence (SL) is explored as a probe of bubble temperature during cavitational collapse discrete intervals along the cavitational collapse time line, thus yielding different cavitation

  13. Using Passive Cavitation Detection to Observe Postexcitation Response of Ultrasound Contrast

    E-Print Network [OSTI]

    Illinois at Urbana-Champaign, University of

    Using Passive Cavitation Detection to Observe Postexcitation Response of Ultrasound Contrast Agents, FR Email: daking3@illinois.edu Abstract-- Passive cavitation detection was used to improve. Keywords - microbubbles; postexcitation; passive cavitation detection; inertial cavitation; flow rate I

  14. Cavitation-Induced Fusion: Proof of Concept

    E-Print Network [OSTI]

    Max I. Fomitchev-Zamilov

    2012-09-09T23:59:59.000Z

    Cavitation-induced fusion (also known as bubble fusion or sonofusion) has been a topic of much debate and controversy and is generally (albeit incorrectly) perceived as unworkable. In this paper we present the theoretical foundations of cavitation-induced fusion and summarize the experimental results of the research conducted in the past 20 years. Based on the systematic study of all available data we conclude that the cavitation-induced fusion is feasible, doable, and can be used for commercial power generation. We present the results of our own research and disclose a commercial reactor prototype.

  15. Frequency dependence of mass flow gain factor and cavitation compliance of cavitating inducers

    SciTech Connect (OSTI)

    Otsuka, S.; Tsujimoto, Yoshinobu [Osaka Univ. (Japan); Kamijo, Kenjiro [National Aerospace Lab., Kakuda, Miyagi (Japan). Kakuda Research Center; Furuya, O. [AMP Technologies, Osaka (Japan)

    1994-12-31T23:59:59.000Z

    Unsteady cavitation characteristics are analyzed based on a closed cavity model in which the length of the cavity is allowed to oscillate. It is shown that the present model blends smoothly into quasisteady calculations in the low frequency limit, unlike fixed cavity length models. Effects of incidence angle and cavitation number on cavitation compliance and mass flow gain factor are shown as functions of reduce frequency. The cavity volume is evaluated by three methods and the results were used to confirm the accuracy and adequacy of the numerical calculation. By comparison with experimental data on inducers, it was shown that the present model can simulate the characteristics of unsteady cavitation qualitatively.

  16. Shear viscosity, cavitation and hydrodynamics at LHC

    E-Print Network [OSTI]

    Jitesh R. Bhatt; Hiranmaya Mishra; V. Sreekanth

    2011-09-28T23:59:59.000Z

    We study evolution of quark-gluon matter in the ultrarelativistic heavy-ion collisions within the frame work of relativistic second-order viscous hydrodynamics. In particular, by using the various prescriptions of a temperature-dependent shear viscosity to the entropy ratio, we show that the hydrodynamic description of the relativistic fluid become invalid due to the phenomenon of cavitation. For most of the initial conditions relevant for LHC, the cavitation sets in very early during the evolution of the hydrodynamics in time $\\lesssim 2 $fm/c. The cavitation in this case is entirely driven by the large values of shear viscosity. Moreover we also demonstrate that the conformal term used in equations of the relativistic dissipative hydrodynamic can influence the cavitation time.

  17. Evaporation-induced cavitation in nanofluidic channels

    E-Print Network [OSTI]

    Karnik, Rohit N.

    Cavitation, known as the formation of vapor bubbles when liquids are under tension, is of great interest both in condensed matter science as well as in diverse applications such as botany, hydraulic engineering, and medicine. ...

  18. Notes 06. Liquid cavitation in fluid film bearings

    E-Print Network [OSTI]

    San Andres, Luis

    2009-01-01T23:59:59.000Z

    NOTES 6. CAVITATION IN LIQUID FILM BEARINGS. Dr. Luis San Andr?s ? 2009 1 NOTES 6. LIQUID CAVITATION IN FLUID FILM BEARINGS Lecture 6 describes the phenomenon of liquid cavitation in steadily loaded fluid film bearings and notes the most... ? Density at Pcav [kg/m 3 ] ? Fluid absolute viscosity [N.s/m 2 ] ? Journal angular speed (rad/s) Subscripts * Inception of the cavitation zone a Ambient value cav Cavitation NOTES 6. CAVITATION IN LIQUID FILM BEARINGS. Dr. Luis San Andr?s ? 2009...

  19. Cavitation from bulk viscosity in neutron stars and quark stars

    E-Print Network [OSTI]

    Jes Madsen

    2009-09-30T23:59:59.000Z

    The bulk viscosity in quark matter is sufficiently high to reduce the effective pressure below the corresponding vapor pressure during density perturbations in neutron stars and strange stars. This leads to mechanical instability where the quark matter breaks apart into fragments comparable to cavitation scenarios discussed for ultra-relativistic heavy-ion collisions. Similar phenomena may take place in kaon-condensed stellar cores. Possible applications to compact star phenomenology include a new mechanism for damping oscillations and instabilities, triggering of phase transitions, changes in gravitational wave signatures of binary star inspiral, and astrophysical formation of strangelets. At a more fundamental level it points to the possible inadequacy of a hydrodynamical treatment of these processes in compact stars.

  20. Cavitation level-acoustic intensity hysteresis: experimental and numerical characterization

    E-Print Network [OSTI]

    Boyer, Edmond

    Cavitation level-acoustic intensity hysteresis: experimental and numerical characterization P such as sonoporation, inertial cavitation is commonly considered as the main candidate inducing membrane poration. Thus, characterizing inertial cavitation, as related to bubble size distribution and medium history, is of great

  1. Extreme conditions during multibubble cavitation: Sonoluminescence as a spectroscopic probe

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Extreme conditions during multibubble cavitation: Sonoluminescence as a spectroscopic probe Kenneth Cavitation MBSL Plasma a b s t r a c t We review recent work on the use of sonoluminescence (SL) to probe spectroscopically the conditions created during cavitation, both in clouds of collapsing bubbles (multibubble

  2. Hot Spot Conditions during Cavitation in Water Yuri T. Didenko,

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Hot Spot Conditions during Cavitation in Water Yuri T. Didenko, William B. McNamara III-13 the effective hot spot temperature during aqueous cavitation remains unresolved. Given the importance of aqueous cavitation (sonography and bioeffects of ultrasound, sonochemical remediation of aqueous pollutants

  3. Energy Minimising Properties of the Radial Cavitation Solution in

    E-Print Network [OSTI]

    Sivaloganathan, J.

    Energy Minimising Properties of the Radial Cavitation Solution in Incompressible Nonlinear in the deformed body. This result has implications for the study of cavitation in certain polymers. Mathematics, radial minimizer, cavitation. 1 #12;2 J. Sivaloganathan and S. J. Spector 1 Introduction. Let B Rn

  4. POLYCONVEX ENERGIES AND CAVITATION P. CELADA S. PERROTTA

    E-Print Network [OSTI]

    Celada, Pietro

    POLYCONVEX ENERGIES AND CAVITATION P. CELADA ­ S. PERROTTA Dedicated to Arrigo Cellina on his to mention a few other references. We mention also [4] for a description of cavitation in the language of currents and we refr to [5] for a survey of theoretical and experimental results about cavitation. Among

  5. NUMERICAL INVESTIGATION OF CAVITATION IN MULTI-DIMENSIONAL COMPRESSIBLE FLOWS

    E-Print Network [OSTI]

    NUMERICAL INVESTIGATION OF CAVITATION IN MULTI-DIMENSIONAL COMPRESSIBLE FLOWS KRISTEN J. DEVAULT, cavitation, pseudospectral AMS subject classifications. 35Q30, 65M70, 76N99 1. Introduction. A long to first make a careful numerical study of the simplest possible scenario where one could expect cavitation

  6. Breakthrough Technologies In Vivo Observation of Cavitation and Embolism Repair

    E-Print Network [OSTI]

    Holbrook, N. Michele

    Breakthrough Technologies In Vivo Observation of Cavitation and Embolism Repair Using Magnetic that approximately 10 vessels had cavitated during this time. Leaf water potentials decreased from 1.25 to 2.1 MPa cavitation. Refilling of xylem vessels occurred as soon as the lights were switched off, with the majority

  7. Double Passive Cavitation Detection of OptisonTM Shell Rupture

    E-Print Network [OSTI]

    Illinois at Urbana-Champaign, University of

    Double Passive Cavitation Detection of OptisonTM Shell Rupture Azzdine Y. Ammi1 , Robin O). The experimental setup is based on a passive cavitation detection system described in previous work. However by ultrasonic capsule destruction [3,4]. In previous work using a passive cavitation detection (PCD) system [5

  8. On Cavitation, Configurational Forces and Implications for Fracture in

    E-Print Network [OSTI]

    Sivaloganathan, J.

    On Cavitation, Configurational Forces and Implications for Fracture in a Nonlinearly Elastic tensile stress can induce cavitation, that is, the appearance of voids that were not previously evident con- sequence of this viewpoint is that cavitation may then take place at a point

  9. Numerical Simulation of Unsteady Three-Dimensional Sheet Cavitation

    E-Print Network [OSTI]

    Twente, Universiteit

    Numerical Simulation of Unsteady Three-Dimensional Sheet Cavitation A.H. Koop #12;Numerical Simulation of Unsteady Three-Dimensional Sheet Cavitation A.H. Koop Thesis University of Twente, Enschede, the Netherlands #12;NUMERICAL SIMULATION OF UNSTEADY THREE-DIMENSIONAL SHEET CAVITATION PROEFSCHRIFT ter

  10. On acoustic cavitation of slightly subcritical bubbles Anthony Harkin

    E-Print Network [OSTI]

    Kaper, Tasso J.

    On acoustic cavitation of slightly subcritical bubbles Anthony Harkin Department of Mathematics threshold indicates the onset of quasistatic evolution leading to cavitation for gas bubbles in liquids identifies a critical radius which separates quasistatically stable bubbles from those which would cavitate

  11. Controlled cavitation in microfluidics Severine Le Gac,2

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Controlled cavitation in microfluidics Ed Zwaan,1 S´everine Le Gac,2 Kinko Tsuji,3 and Claus-Hahn-Strasse 6-10, D-47269 Duisburg, Germany. (Dated: February 20, 2007) We report on cavitation in confined microscopic environments which are commonly called microfluidic or lab-on-a-chip systems. The cavitation

  12. Measurements of Cavitation Dose, Echogenicity, and Temperature during Ultrasound Ablation

    E-Print Network [OSTI]

    Mast, T. Douglas

    Measurements of Cavitation Dose, Echogenicity, and Temperature during Ultrasound Ablation T traces from the array, time-domain signals received by a 1 MHz, unfocused passive cavitation detector signals received by the array. Cavitation dose was quantified from the spectra of signals measured

  13. Cavitation in holographic sQGP

    E-Print Network [OSTI]

    Aleksandra Klimek; Louis Leblond; Aninda Sinha

    2011-04-05T23:59:59.000Z

    We study the possibility of cavitation in the nonconformal N=2^* SU(N) theory which is a mass deformation of N=4 SU(N) Yang-Mills theory. The second order transport coefficients are known from the numerical work using AdS/CFT by Buchel and collaborators. Using these and the approach of Rajagopal and Tripuraneni, we investigate the flow equations in a 1+1 dimensional boost invariant set up. We find that the string theory model does not exhibit cavitation before phase transition is reached. We give a semi-analytic explanation of this finding.

  14. The influence of metallurgical variables on the temperature dependence of irradiation hardening in pressure vessel steels

    SciTech Connect (OSTI)

    Odette, G.R.; Lucas, G.E.; Klingensmith, R.D. [Univ. of California, Santa Barbara, CA (United States). Dept. of Mechanical Engineering

    1996-12-31T23:59:59.000Z

    Yield stress elevations ({Delta}{sigma}{sub y}) in pressure vessel steels irradiated at intermediate flux and fluence systematically decreased with increasing temperature and decreasing copper and nickel content. Lower stress relief temperature also decreased {Delta}{sigma}{sub y} at bulk copper concentrations greater than about 0.3%. The dependence of {Delta}{sigma}{sub y} on irradiation temperature between 260 and 316 C increased with copper and nickel content and decreased with phosphorus content. When normalized by the average {Delta}{sigma}{sub y}, the fractional temperature dependence correlates with a simple empirical chemistry factor of copper and phosphorus. The correlation predicts data on the irradiation temperature dependence of {Delta}{sigma}{sub y} found in the literature within a standard error of about 0.3 MPa/{degree}C and is consistent with current understanding of hardening mechanisms. However, questions remain about the effects at very low flux and finer scale variations over smaller temperature intervals.

  15. A novel way of detecting transient cavitation near a solid surface during megasonic cleaning using electrochemical impedance spectroscopy

    E-Print Network [OSTI]

    Deymier, Pierre

    A novel way of detecting transient cavitation near a solid surface during megasonic cleaning using Keywords: Megasonic cleaning Transient cavitation Acoustic streaming Microelectrode Electrochemical to transient cavitation. Development of a method to monitor transient cavitation events in solutions irradiated

  16. 305Sec. 4-9 Pump Placement To Avoid Cavitation -r-;0-J.s;,

    E-Print Network [OSTI]

    Kostic, Milivoje M.

    305Sec. 4-9 Pump Placement To Avoid Cavitation 6o q -.:.. 1.01 ll.oo -r-;0- J.s;, with permission, Worthington Division, McGraw-Edison Co.) changes in the downstream direction until the pump inletHt - g - (4-35a)Pfgc Pressure in suction tank P, Suction pressure Pump FIGURE 4-43 System schematic

  17. Characterization of transient cavitation in gas sparged solutions exposed to megasonic field using cyclic voltammetry

    E-Print Network [OSTI]

    Deymier, Pierre

    Characterization of transient cavitation in gas sparged solutions exposed to megasonic field using 2011 Keywords: Megasonic energy Transient cavitation Acoustic streaming Dissolved gases Microelectrode been a significant interest in understanding the phenomena of cavitation and acoustic streaming, which

  18. Electrochemical investigations of stable cavitation from bubbles generated during reduction of water

    E-Print Network [OSTI]

    Deymier, Pierre

    Electrochemical investigations of stable cavitation from bubbles generated during reduction April 2014 Keywords: Megasonic cleaning Stable cavitation Microstreaming Hydrogen bubbles Water on wafers without affect- ing the transient cavitation responsible for feature damage. ? 2014 Elsevier B

  19. On the construction and properties of weak solutions describing dynamic cavitation

    E-Print Network [OSTI]

    Miroshnikov, Alexey

    On the construction and properties of weak solutions describing dynamic cavitation (In: Journal associated with dynamically cavitating solutions coincides with the critical stretching in the bifurcation with contents. Keywords: Cavitation, Shock wave, Polyconvex elasticity Mathematics Subject Classification: 35L67

  20. Predictors of cavitation in glassy polymers under tensile strain: a coarse grained molecular dynamics

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Predictors of cavitation in glassy polymers under tensile strain: a coarse grained molecular the cavity position before the cavitation occurs. Even if the localization of a cavity is not directly: Cavitation, Plasticity, Computational modeling, Molecular dynamics simulation, Mechanical properties. 1

  1. Creation of cavitation activity in a microfluidic device through acoustically driven capillary waves

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Creation of cavitation activity in a microfluidic device through acoustically driven capillary acoustic cavitation generated by ultrasonic vibrations in polydimethylsiloxane (PDMS) based microfluidic in the microfluidic channels. Also, it is observed that nuclei leading to intense inertial cavitation are generated

  2. A NEW CAVITATION MODEL IN LUBRICATION: THE CASE OF TWOZONE CAVITATION GUSTAVO C. BUSCAGLIA, IONEL CIUPERCA, ERIC DALISSIER, AND MOHAMMED JAI

    E-Print Network [OSTI]

    Buscaglia, Gustavo C.

    A NEW CAVITATION MODEL IN LUBRICATION: THE CASE OF TWO­ZONE CAVITATION GUSTAVO C. BUSCAGLIA, IONEL of cavitation in lubricated devices is proposed, such that the translation velocity V for the saturation field of course the cavitation boundary leaves the domain or disappears. A few preliminary numerical examples

  3. Conference title. Thomas Telford, London, 2003 Pressure Chamber Testing of Model

    E-Print Network [OSTI]

    Byrne, Byron

    the coast of the United Kingdom. In the first instance many of the wind turbine structures will be founded. These indicated that significant tensile capacities are possible and are limited by cavitation of the pore fluid suction pressure is limited by cavitation of the pore fluid, the maximum available suction is much lower

  4. Mechanical Damage from Cavitation in High Intensity Focused Ultrasound Accelerated Thrombolysis

    E-Print Network [OSTI]

    Weiss, Hope

    2012-01-01T23:59:59.000Z

    Mechanical Damage . . . . . . . . . . . . . . . . . .iiiMethod for Estimation of Cavitation Damage for an EmbeddedMethod for Estimation of Cavitation Damage for an Embedded

  5. Chemical Applications of Electrohydraulic Cavitation for Hazardous Waste Control

    E-Print Network [OSTI]

    Hoffmann, M. R.

    CHEMICAL APPLICATIONS OF ELECTROHVDRAULIC CAVITATION FOR HAZARDOUS WASTE CONTROL MICHAEL R. HOFFMANN, PROFESSOR, CALIFORNIA INSTITUTE OF TECHNOLOGY, PASADENA, CA 91125 Abstract We have been investigating the fundamental chemistry..., production of hydroxyl radicals, hydrogen atoms, hydrogen peroxide and aquated electrons. The chemical changes of compounds in water pulsed with these different sources of power are induced in part by the violent collapse of cavitation bubbles...

  6. Cavitation in normal liquid helium 3 F. Caupin, P. Roche, S. Marchand and S. Balibar

    E-Print Network [OSTI]

    Caupin, Frédéric

    Cavitation in normal liquid helium 3 F. Caupin, P. Roche, S. Marchand and S. Balibar Laboratoire de 24 rue Lhomond 75231 Paris Cedex 05, France We have studied cavitation, i.e. bubble nucleation, cavitation is found to be stochastic, with a cavitation probability 0.5 at a given value of the sound

  7. Proceedings of the 8th International Symposium on Cavitation CAV2012 -Abstract No. 153

    E-Print Network [OSTI]

    Mahesh, Krishnan

    Proceedings of the 8th International Symposium on Cavitation CAV2012 - Abstract No. 153 August 14-16, 2012, Singapore TOWARDS NUMERICAL SIMULATION OF CAVITATING FLOWS IN COMPLEX GEOMETRIES Aswin for benchmark problems and applied to a cavitating flow over a circular cylinder. INTRODUCTION Cavitation occurs

  8. Conservative one-dimensional finite volume discretization of a new cavitation model for pistonring lubrication

    E-Print Network [OSTI]

    Buscaglia, Gustavo C.

    Conservative one-dimensional finite volume discretization of a new cavitation model for piston Cavitation Elrod­Adams model Piston­rings a b s t r a c t This paper presents a conservative numerical implementation of a new cavitation model that is well suited for lubrication problems with cavitated regions

  9. acoustic cavitation of slightly subcritical bubbles of Mathematics, Boston University, Boston, Massachusetts 02215

    E-Print Network [OSTI]

    Harkin, Anthony

    On acoustic cavitation of slightly subcritical bubbles Anthony ¡ Harkin Department Blake threshold indicates the onset of quasistatic evolution leading to cavitation for gas§ bubbles would cavitate. In this work, we analyze the cavitation threshold for radially symmetric bubbles whose

  10. Preprint version -March 7, 2006 REITERATED HOMOGENIZATION OF A CAVITATION PROBLEM

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Preprint version - March 7, 2006 REITERATED HOMOGENIZATION OF A CAVITATION PROBLEM IN THIN FILMS theory: cavitation phenomena and roughness of the surfaces in relative motion: cavitation is defined to describe the behavior of a viscous cavitated flow in the lubrication framework. However, in practical

  11. Cavitation in an orifice flow S. Dabiri and W. A. Sirignano

    E-Print Network [OSTI]

    Joseph, Daniel D.

    Cavitation in an orifice flow S. Dabiri and W. A. Sirignano Department of Mechanical and Aerospace locations for cavitation induced by total stress on the flow of a liquid through an orifice of an atomizer. The total-stress criterion for cavitation is applied to find the regions where cavitation is likely to occur

  12. Cavitation-induced ignition of cryogenic hydrogen-oxygen fluids V. V. Osipov,1,a

    E-Print Network [OSTI]

    Muratov, Cyrill

    Cavitation-induced ignition of cryogenic hydrogen-oxygen fluids V. V. Osipov,1,a C. B. Muratov,2 E-ignite in the process of their sudden mixing. Here, we propose a cavitation-induced self-ignition mechanism that may a cavitation-induced self- ignition mechanism of cryogenic H2/Ox fluids. Cavitation is the formation

  13. Application of Wireless Sensor Network (WSN) Technologies in Optimal Static Pressure Reset in Variable Air Volume (VAV) System

    E-Print Network [OSTI]

    Zheng, K.; Li, H.; Yang, H.

    2007-01-01T23:59:59.000Z

    Optimization of the static pressure reset is always critical in the pursuit of maximum savings of fan power and thermal energy consumption in a VAV system. This paper theoretically investigated three static pressure reset methods, i.e. VAV terminal...

  14. A study of capillary pressure in a partly saturated quartz powder

    E-Print Network [OSTI]

    Burke, Jack Willard, Jr

    1964-01-01T23:59:59.000Z

    3-2. Principle of the Direct Suction Method. of Measuring Soil Suction contents. Suctions greater than one atmosphere cannot be measured as the water in the measuring system will vaporize or cavitate. The direct suction method (Figure 3-2) covers.... This does not effect the capillary pressure, which is the difference between the air and water across the menisci formed in the disc and. sample, but it does relieve negative pressure in the measuring system water. Therefore the cavitation...

  15. ACOUSTIC CAVITATION ASSESSMENT OF THE REVERSIBILITY AND PERMEABILITY OF THE ULTRASOUND-INDUCED BLOOD-BRAIN BARRIER OPENING

    E-Print Network [OSTI]

    Konofagou, Elisa E.

    ACOUSTIC CAVITATION ASSESSMENT OF THE REVERSIBILITY AND PERMEABILITY cavitation can be potentially used to assess the reversibility and permeability of the induced BBB opening. Method: This study links the microbubble dynamics, represented by the cavitation dose, as monitored

  16. Reproducible cavitation activity in water-particle suspensions Bram M. Borkent, Manish Arora, and Claus-Dieter Ohla

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Reproducible cavitation activity in water-particle suspensions Bram M. Borkent, Manish Arora January 2007 The study of cavitation inception in liquids rarely yields reproducible data, unless special technique is demonstrated which allows repeatable measurements of cavitation activity in liquid

  17. Summary Xylem vulnerability to cavitation is a promising criterion for identifying trees with high drought tolerance, but

    E-Print Network [OSTI]

    Mencuccini, Maurizio

    Summary Xylem vulnerability to cavitation is a promising criterion for identifying trees with high drought tolerance, but traditional techniques for measuring cavitation resistance are unsuitablefor throughput screening of cavitation resistance in five poplar (Populus spp.) andfour willow (Salix spp

  18. Simulations of Variable Bottomhole Pressure Regimes to Improve Production from the Double-Unit Mount Elbert, Milne Point Unit, North Slope Alaska Hydrate Deposit

    SciTech Connect (OSTI)

    Myshakin, Evgeniy; Anderson, Brian; Rose, Kelly; Boswell, Ray

    2011-01-01T23:59:59.000Z

    Gas production was predicted from a reservoir model based on the Mount Elbert gas hydrate accumulation located on the Alaska North slope at various simulator submodels and production scenarios. Log, core, and fluid measurements were used to provide a comprehensive reservoir description. These data were incorporated with experimentally derived saturations, porosities, permeability values, parameters for capillary pressure, and relative permeability functions. The modeled reservoir exposed to depressurization at a constant bottomhole pressure (2.7 MPa) has shown limited production potential due to its low temperature profile. To improve production the bottomhole pressure was allowed to vary from 2.7 (above the quadruple point) to 2.0 MPa over a 15-year period. The results indicate that gas production was nearly doubled in comparison with a constant-pressure regime. Extensive ice formation and hydrate reformation that could severely hinder gas production were avoided in the variable-pressure regime system. A use of permeability variation coupled with porosity change is shown to be crucial to predict those phenomena at a reservoir scale.

  19. atmospheric interest cavites: Topics by E-print Network

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

    Vagins; G. Varner; R. Wagner; M. Wetstein; L. Winslow; M. Yeh 2014-02-26 2 Quantum Cavitation Quantum Physics (arXiv) Summary: We consider the theoretical setting of a superfluid...

  20. Comparison and Validation of Compressible Flow Simulations of Laser-Induced Cavitation

    E-Print Network [OSTI]

    Comparison and Validation of Compressible Flow Simulations of Laser-Induced Cavitation Bubbles)). The validation is performed for the case of laser-induced cavitation bubbles collapsing in an infinite medium

  1. The use of cavitation for the production of diver breathing gas

    E-Print Network [OSTI]

    Klentzman, Chris Adam

    1990-01-01T23:59:59.000Z

    to produce the necessary vacuum in the cylinder. Various water samples were cavitated by placing them in a vacuum developed in the piston/cylinder assembly. The water samples varied in temperature, volume, and salinity to determine the corre-, lations... PRODUCED BY THE CAVITATION PROCESS AND THEIR BASIC DIMENSIONS. 2. DIMENSIONLESS PARAMETERS FOR ANALYSIS OF THE VOLUME OF GAS PRODUCED BY CAVITATION 3. WATER SAMPLES CAVITATED FOR GAS ANALYSIS 4. MICRO-SCHOLANDER READINGS AND ANALYSIS FOR ALL TESTED...

  2. Proceedings of the 8th International Symposium on Cavitation CAV2012 -Abstract No. 198

    E-Print Network [OSTI]

    Shyue, Keh-Ming

    Proceedings of the 8th International Symposium on Cavitation CAV2012 - Abstract No. 198 August 14-PHASE FLOW WITH CAVITATION Keh-Ming Shyue Department of Mathematics National Taiwan University Taipei, Taiwan for the efficient numerical simulation of compressible two-phase flow with cavitation. The algorithm uses a five

  3. Modeling for non isothermal cavitation using four-equation Eric Goncalv`es

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Modeling for non isothermal cavitation using four-equation models Eric Goncalv`es LEGI-fluid solver has been developed to investigate the behaviour of cavitation models including thermodynamic between phases are studied. Numerical simulations are firstly performed on rarefaction cavitating problems

  4. ON THE DrFF,US~VE CAVITATION OF ISOLATED GRAIN BOUNDARY FACETS TN

    E-Print Network [OSTI]

    ON THE DrFF,US~VE CAVITATION OF ISOLATED GRAIN BOUNDARY FACETS TN CREEPING POLYCRYSTALS J. R. RICE-Following concepts introduced by B. F. Dyson (Metal Sci.349 19761,the dilTusive cavitation of grain facets is considered in circumstances for which the cavitated fasts are well separated from one another. In this case

  5. Controlled Multibubble Surface Cavitation Nicolas Bremond,* Manish Arora, Claus-Dieter Ohl, and Detlef Lohse

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Controlled Multibubble Surface Cavitation Nicolas Bremond,* Manish Arora, Claus-Dieter Ohl been notorious because of its irreproducibility. Here controlled multibubble surface cavitation of the cavitation events where the inner bubbles in the two- dimensional cluster are shielded by the outer ones

  6. Capacitive effect of cavitation in xylem conduits: results from a dynamic model

    E-Print Network [OSTI]

    Mencuccini, Maurizio

    Capacitive effect of cavitation in xylem conduits: results from a dynamic model TEEMU H?LTT?1. A dynamic model is presented that models xylem water potential, xylem sap flow and cavitation, taking; xylem transport. INTRODUCTION Xylem embolism formation by cavitation causes a decrease in plant

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

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

  8. Proceedings of the 8th International Symposium on Cavitation CAV2012 -Abstract No. #240

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Proceedings of the 8th International Symposium on Cavitation CAV2012 - Abstract No. #240 August 14-16, 2012, Singapore STUDY OF PASSIVE CONTROL STUDY OF THE CAVITATION INSTABILITY ON A VENTURI PROFILE Am SUMMARY As a source of vibrations, noise, erosion and structure dam- ages, cavitation is a major handicap

  9. Cavitation and the state of stress in a flowing liquid Daniel D. Joseph

    E-Print Network [OSTI]

    Joseph, Daniel D.

    Cavitation and the state of stress in a flowing liquid Daniel D. Joseph University of Minnesota The problem of the inception of cavitation is formulated in terms of a compar- ison of the breaking strength or cavitation threshold at each point of a liquid sam- ple with the principal stresses there. A criterion

  10. Journal of Fluids and Structures 20 (2005) 753762 Fluidstructure interaction and transient cavitation tests in a

    E-Print Network [OSTI]

    Tijsseling, A.S.

    cavitation tests in a T-piece pipe A.S. Tijsselinga,?, A.E. Vardyb a Department of Mathematics and Computer­structure interaction (FSI) and vaporous cavitation is presented. The model is a closed, water-filled, T of the cavitation phenomenon. r 2005 Elsevier Ltd. All rights reserved. Keywords: Water hammer; Fluid

  11. Prevention of tissue damage by water jet during cavitation Daniel Palanker,a)

    E-Print Network [OSTI]

    Palanker, Daniel

    Prevention of tissue damage by water jet during cavitation Daniel Palanker,a) Alexander Vankov Cavitation bubbles accompany explosive vaporization of water following pulsed energy deposition in liquid can produce tissue damage at a distance exceeding the radius of the cavitation bubble by a factor of 4

  12. Birth and Growth of Cavitation Bubbles within Water under Tension Confined in a Simple Synthetic Tree

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Birth and Growth of Cavitation Bubbles within Water under Tension Confined in a Simple Synthetic. Cavitation can spontaneously occur, nucleating a bubble. We investigate the dynamics of spontaneous or triggered cavitation inside water filled microcavities of a hydrogel. Results show that a stable bubble

  13. ImageGuided Ex vivo Liver Ablation by Unfocused Ultrasound using Passive Cavitation Detection

    E-Print Network [OSTI]

    Mast, T. Douglas

    Image­Guided Ex vivo Liver Ablation by Unfocused Ultrasound using Passive Cavitation Detection echogenicity from image brightness. Passively detected acoustic emissions are used to quantify cavitation and cavitation. The latter two quantities can potentially be monitored noninvasively and used as a surrogate

  14. Cavitation induced by explosion in an ideal fluid model Christophe Josserand*

    E-Print Network [OSTI]

    Cavitation induced by explosion in an ideal fluid model Christophe Josserand* The James Franck a cavitation bubble for large enough energy. This gives a consistent view for rebound bubbles in superfluid.55.Bx, 67.55.Fa, 64.70.Fx I. INTRODUCTION Cavitation is a physical process involving such aspects

  15. Plasma Line Emission during Single-Bubble Cavitation David J. Flannigan and Kenneth S. Suslick*

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Plasma Line Emission during Single-Bubble Cavitation David J. Flannigan and Kenneth S. Suslick-bubble cavitation in sulfuric acid are reported. The excited states responsible for these emission lines range 8.3 e the plasma generated during cavitation is comprised of highly energetic particles. DOI: 10.1103/Phys

  16. Xylem cavitation caused by drought and freezing stress in four co-occurring Juniperus species

    E-Print Network [OSTI]

    Jackson, Robert B.

    Xylem cavitation caused by drought and freezing stress in four co-occurring Juniperus species: 10.1111/j.1399-3054.2006.00644.x Previous studies indicate that conifers are vulnerable to cavitation cavitation, along with wood density, conduit reinforcement, trac- heid diameter, and hydraulic conductivity

  17. In vivo transcranial cavitation threshold detection during ultrasound-induced bloodbrain barrier opening in mice

    E-Print Network [OSTI]

    Konofagou, Elisa E.

    In vivo transcranial cavitation threshold detection during ultrasound-induced blood­brain barrier cavitation threshold detection during ultrasound-induced blood­brain barrier opening in mice Yao-Sheng Tung1 cavitation response associated with blood­brain barrier (BBB) opening as induced by transcranial focused

  18. Chemistry Induced by Hydrodynamic Cavitation Kenneth S. Suslick,* Millan M. Mdleleni, and

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Chemistry Induced by Hydrodynamic Cavitation Kenneth S. Suslick,* Millan M. Mdleleni, and Jeffrey T, Urbana, Illinois 61801 ReceiVed July 1, 1997 Cavitation (the formation, growth, and implosive collapse the chemical effects of acoustic cavitation (i.e., sonochemistry and sonoluminescence) have been extensively

  19. A CAVITATION TRACKING METHOD FOR ELASTIC-PLASTIC FLOW IN SOLIDS

    E-Print Network [OSTI]

    Shyue, Keh-Ming

    A CAVITATION TRACKING METHOD FOR ELASTIC-PLASTIC FLOW IN SOLIDS Keh-Ming Shyue Department with cavitation. The algorithm uses a simplified model system where the behavior of the materials is modeled, and the von Mises condition for the elastic-plastic phase change. To characterize the cavitation

  20. Modeling for isothermal cavitation with a four-equation model Eric Goncalv`es

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Modeling for isothermal cavitation with a four-equation model Eric Goncalv`es , Boris Charri-dimensional inviscid cavitating tube problems. This mass transfer term appears explicitly as a source term of a void realistic cavitating flows. Numerical results are given for various inviscid cases (underwater explosion

  1. Hydrodynamic cavitation and boiling in refrigerant (R-123) flow inside microchannels

    E-Print Network [OSTI]

    Peles, Yoav

    Hydrodynamic cavitation and boiling in refrigerant (R-123) flow inside microchannels Brandon cavitation has on heat transfer. The fluid medium is refrigerant R-123 flowing through 227 lm hydraulic diameter microchannels. The cavitation is instigated by the inlet orifice. Adiabatic tests were con- ducted

  2. Cavitation Inception on Microparticles: A Self-Propelled Particle Accelerator Manish Arora,1

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Cavitation Inception on Microparticles: A Self-Propelled Particle Accelerator Manish Arora,1 Claus) Corrugated, hydrophilic particles with diameters between 30 and 150 m are found to cause cavitation inception of the particle and the displaced liquid. The analysis suggests that all particles which cause cavitation

  3. Luminescence from acoustic-driven laser-induced cavitation bubbles Claus-Dieter Ohl*

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Luminescence from acoustic-driven laser-induced cavitation bubbles Claus-Dieter Ohl* Drittes and on the cavitation luminescence of a transient laser-induced bubble is investigated experimentally. The variation.60.Mq, 47.55.Bx, 47.55.Dz A vast concentration of energy occurs during the collapse of a cavitation

  4. SYMPOSIUM PAPER Simulation of the effects of cavitation and anatomy in the shock

    E-Print Network [OSTI]

    Dabiri, John O.

    SYMPOSIUM PAPER Simulation of the effects of cavitation and anatomy in the shock path of model types of tissue encountered along the shock path, and by the presence of cavitation bubbles that attempt to characterize the mechanisms by which collapsing cavitation models erode stones, and by which

  5. Drought experience and cavitation resistance in six shrubs from the Great Basin, Utah

    E-Print Network [OSTI]

    Hacke, Uwe

    Drought experience and cavitation resistance in six shrubs from the Great Basin, Utah Uwe G. Hacke capability of the xylem. This is due to drought-induced cavitation. We used the centrifuge method to measure the vulnerability of root and stem xylem to cavitation in six native shrub species. The shrubs fall into three

  6. Molecular and atomic emission during single-bubble cavitation in concentrated sulfuric acid

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Molecular and atomic emission during single- bubble cavitation in concentrated sulfuric acid David during cavitation. Single-bubble sonoluminescence (SBSL) from sulfuric acid (H2SO4) is much brighter than occurring during single- bubble cavitation. In fact, SBSL spectra from organic liquids8,9 have been

  7. PAPER www.rsc.org/loc | Lab on a Chip Laser-induced cavitation based micropump

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    PAPER www.rsc.org/loc | Lab on a Chip Laser-induced cavitation based micropump Rory Dijkinka as versatile and robust pumping techniques. Here, we present a cavitation based technique, which is able cavitation event is created by focusing a laser pulse in a conventional PDMS microfluidic chip close

  8. A creep model for austenitic stainless steels incorporating cavitation and wedge cracking

    E-Print Network [OSTI]

    Mahesh, Sivasambu

    A creep model for austenitic stainless steels incorporating cavitation and wedge cracking S Mahesh evolution in the form of cavitation and wedge- cracking on grain boundary facets is considered. Both: Austenitic stainless steel, creep, grain boundary sliding, cavitation, wedge- cracking. Submitted to

  9. Cavitation and the state of stress in a flowing liquid Daniel D. Joseph

    E-Print Network [OSTI]

    Joseph, Daniel D.

    Cavitation and the state of stress in a flowing liquid Daniel D. Joseph University of Minnesota The problem of the inception of cavitation is formulated in terms of a compar­ ison of the breaking strength or cavitation threshold at each point of a liquid sam­ ple with the principal stresses there. A criterion

  10. Response to ``Comment on `Ultrasound-induced lung hemorrhage is not caused by inertial cavitation'''

    E-Print Network [OSTI]

    Illinois at Urbana-Champaign, University of

    Response to ``Comment on `Ultrasound-induced lung hemorrhage is not caused by inertial cavitation cavitation nuclei in lung versus other tissues such that overpressure does not affect the inertial cavitation threshold in lung, then there would be an impact on the con- clusion in our publication.2 To examine

  11. Comment on ``Ultrasound-induced lung hemorrhage is not caused by inertial cavitation''

    E-Print Network [OSTI]

    Illinois at Urbana-Champaign, University of

    Comment on ``Ultrasound-induced lung hemorrhage is not caused by inertial cavitation'' [J. Acoust1297 2000 that ultrasound-induced lung hemorrhage is not caused by inertial cavitation. An argument is provided that illustrates how cavitation inception conditions in the lungs of animals are not altered

  12. Cavitation within a dropletCavitation within a droplet G. L. Heijnen1,2, P. A. Quinto-Su2, X. Zhao2, C. D. Ohl1,2

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Cavitation within a dropletCavitation within a droplet G. L. Heijnen1,2, P. A. Quinto-Su2, X. Zhao2 University, Singapore. A cavitation bubble expanding and collapsing inside a liquid droplet creates two high jets taken 400µs after the cavitation bubble has been created. The central jet is surrounded

  13. Cavitation rheology for soft materials Jessica A. Zimberlin, Naomi Sanabria-DeLong, Gregory N. Tew and Alfred J. Crosby*

    E-Print Network [OSTI]

    Tew, Gregory N.

    Cavitation rheology for soft materials Jessica A. Zimberlin, Naomi Sanabria-DeLong, Gregory N. Tew the modulus local to the site of cavitation, heterogeneities within a material can easily be probed systems. 2. Experimental 2.1 Cavitation rheology technique (CRT) Cavitation rheology involves quantifying

  14. Prediction of Small-Scale Cavitation in a High Speed Flow Over an Open Cavity Using Large Eddy

    E-Print Network [OSTI]

    Apte, Sourabh V.

    Prediction of Small-Scale Cavitation in a High Speed Flow Over an Open Cavity Using Large Eddy- gether with the cavitation models predict that inception occurs near the trailing edge similar in cavitation. 1 INTRODUCTION The problem of cavitation has been widely studied owing to its influence

  15. Effect of austempering temperature on cavitation behaviour of unalloyed ADI material

    SciTech Connect (OSTI)

    Dojcinovic, Marina [University of Belgrade, Faculty of Technology and Metallurgy, Karnegijeva 4, Belgrade (Serbia); Eric, Olivera [Innovation Centre, Faculty of Mechanical Engineering, University of Belgrade, Kraljice Marije 16, Belgrade (Serbia); Rajnovic, Dragan; Sidjanin, Leposava [Department of Production Engineering, Faculty of Technical Sciences, University of Novi Sad, Trg Dositeja Obradovi?a 6, Novi Sad (Serbia); Balos, Sebastian, E-mail: sebab@uns.ac.rs [Department of Production Engineering, Faculty of Technical Sciences, University of Novi Sad, Trg Dositeja Obradovi?a 6, Novi Sad (Serbia)

    2013-08-15T23:59:59.000Z

    This paper provides an in-depth study and description of cavitation damage and microstructural changes in two types of unalloyed austempered ductile iron (ADI). ADI materials used were austempered at 300 and 400 C having ausferrite microstructure with 16 and 31.4% of retained austenite, respectively. Metallographic examination was carried out to study the morphology of their cavitation-damaged surfaces. Cavitation damage was initiated at graphite nodules as well as in the interface between a graphite nodule and an ausferrite matrix. Furthermore, microcracking and ferrite/retained austenite morphology were proved to be of great importance for cavitation resistance. Mass loss rate revealed that ADI austempered at 400 C has a higher cavitation resistance in water than ADI austempered at 300 C. A higher amount of retained austenite in ADI austempered at 400 C played an important role in increasing cavitation resistance. The good cavitation behaviour of ADI austempered at 400 C was due to the matrix hardening by stress assisted phase transformation of retained austenite into martensite (SATRAM) phenomenon, as shown by X-ray diffraction analysis. - Highlights: Cavitation rate of two ADI materials was tested. ADI material with a lower hardness has had a lower cavitation rate. The main reason is microstructural transformations during cavitation. SATRAM phenomenon increases cavitation resistance.

  16. Compressible Effects Modelling in Turbulent Cavitating Jean Decaix

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Nomenclature c speed of sound Cp, Cv thermal capacities E total energy Corresponding author. Email address area because of the drastic diminution of the speed of sound. The detailed mechanisms cavitation number total stress tensor specific dissipation ()L liquid value ()V vapour value ()v viscous

  17. EXPERIMENTS AND CORRESPONDING CALCULATIONS ON THERMOHYDRAULIC PRESSURE SURGES IN PIPES

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    phenomena. A decision must be made whether the numerous effects that can occur during a transient event and 120 °C and pressures between 1 bar and 20 bar comprise the effects of vaporous and gaseous cavitation and simulated data could be achieved. From the numerical simulations it could be assessed, which effects

  18. 17 `eme Congr`es Francais de Mecanique Troyes, 29 ao^ut -2 septembre 2005 Localisation et attenuation dans les cavites acoustiques irreguli`eres

    E-Print Network [OSTI]

    Asch, Mark

    enuation dans les cavites acoustiques irreguli`eres Simon Felix1 , Mark Asch2 , Marcel Filoche1,3 et Bernard

  19. Dynamique d'une bulle cylindrique de cavitation : tude analytique et validation de la mthode

    E-Print Network [OSTI]

    Dynamique d'une bulle cylindrique de cavitation : étude analytique et validation de la méthode. Introduction La présente étude a pour objectif dans un premier temps d'étudier analytiquement la cavitation permettra par la suite d'étudier la cavitation numériquement. La méthode numérique Lagrangienne SPH est

  20. Comment on "Nuclear Emissions During Self-Nucleated Acoustic Cavitation"

    E-Print Network [OSTI]

    B. Naranjo

    2006-09-12T23:59:59.000Z

    In a recent Letter to PRL, Taleyarkhan and coauthors claim to observe DD fusion produced by acoustic cavitation. Among other evidence, they provide a proton recoil spectrum that they interpret as arising from 2.45 MeV DD fusion neutrons. My analysis concludes the spectrum is inconsistent with 2.45 MeV neutrons, cosmic background, or a PuBe source, but it is consistent with a Cf-252 source.

  1. Summary We tested the hypothesis that greater cavitation resistance correlates with less total inter-vessel pit area per ves-

    E-Print Network [OSTI]

    Hacke, Uwe

    Summary We tested the hypothesis that greater cavitation resistance correlates with less total cavitation safety and transport efficiency. Fourteen species of diverse growth form (vine, ring- and diffuse species total). Two types of vulnerability-to-cavitation curves were found. Ring-porous trees and vines

  2. Passive cavitation imaging with ultrasound arrays Vasant A. Salgaonkar, Saurabh Datta, Christy K. Holland, and T. Douglas Masta

    E-Print Network [OSTI]

    Mast, T. Douglas

    Passive cavitation imaging with ultrasound arrays Vasant A. Salgaonkar, Saurabh Datta, Christy K September 2009 A method is presented for passive imaging of cavitational acoustic emissions using, stable and inertial cavitation was passively imaged in saline solution sonicated at 520 kHz. Bubble

  3. Ecological differentiation in xylem cavitation resistance is associated with stem and leaf structural traitspce_2231 137..148

    E-Print Network [OSTI]

    Sack, Lawren

    Ecological differentiation in xylem cavitation resistance is associated with stem and leaf ABSTRACT Cavitation resistance is a critical determinant of drought tolerance in tropical tree species how vulnerability to cavitation (P50) related to dry season leaf water poten- tials and stem and leaf

  4. A finite element approach to study cavitation instabilities in non-linear elastic solids under general loading conditions

    E-Print Network [OSTI]

    Lopez-Pamies, Oscar

    A finite element approach to study cavitation instabilities in non-linear elastic solids under a b s t r a c t This paper proposes an effective numerical method to study cavitation instabilities a single infinitesimal defect at its center. The occurrence of cavitation is identified as the event when

  5. Feasibility of noninvasive cavitation-guided blood-brain barrier opening using focused ultrasound and microbubbles in nonhuman

    E-Print Network [OSTI]

    Konofagou, Elisa E.

    Feasibility of noninvasive cavitation-guided blood-brain barrier opening using focused ultrasound://apl.aip.org/about/rights_and_permissions #12;Feasibility of noninvasive cavitation-guided blood-brain barrier opening using focused ultrasound 2011; published online 20 April 2011 In vivo transcranial and noninvasive cavitation detection

  6. Cavitation in flow through a micro-orifice inside a silicon microchannel Chandan Mishra and Yoav Pelesa)

    E-Print Network [OSTI]

    Peles, Yoav

    Cavitation in flow through a micro-orifice inside a silicon microchannel Chandan Mishra and Yoav) Hydrodynamic cavitation in flows through a micro-orifice entrenched in a microchannel has been detected. The flow of de-ionized water through the micro-orifice reveals the presence of multifarious cavitating flow

  7. Cavitation inception following shock wave passage Department of Applied Physics, TU Twente, Postbus 217, 7500 AE Enschede, The Netherlands

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Cavitation inception following shock wave passage C. D. Ohl Department of Applied Physics, TU; published 5 September 2002 Cavitation bubble nucleation following the passage of an extracorporeal shock of the bubble center; however, considerable disagreement between a simple cavitation inception theory

  8. Quantum Cavitation: a comparison between superfluid helium-4 and normal liquid helium-3

    E-Print Network [OSTI]

    Caupin, Frédéric

    Quantum Cavitation: a comparison between superfluid helium-4 and normal liquid helium-3 S. Balibar in superfluid helium-4 and in normal liquid helium-3, both theoretically and experimentally. We compare the two by tunneling, to classical cavitation where their nu- cleation is thermally activated. In helium-3, where

  9. EUROMECH Young Scientist Prize Paper "Cavitation in rubber: The role of elasticity"

    E-Print Network [OSTI]

    Lopez-Pamies, Oscar

    EUROMECH Young Scientist Prize Paper "Cavitation in rubber: The role of elasticity" AUTHOR won suddenly "appear" in the interior of rubber. This phenomenon has come to be popularly known as cavitation. It corresponds, at heart, to nothing more than to the growth of defects inherent in rubber. Such defects can

  10. Ultrasound-induced lung hemorrhage is not caused by inertial cavitation

    E-Print Network [OSTI]

    Illinois at Urbana-Champaign, University of

    Ultrasound-induced lung hemorrhage is not caused by inertial cavitation William D. O'Brien, Jr, the pathogenesis of lung hemorrhage due to exposure to clinical diagnostic levels of ultrasound has been attributed that directly contradict the hypothesis that ultrasound-induced lung hemorrhage is caused by inertial cavitation

  11. Prediction of the reversibility of the ultrasound-induced blood-brain barrier opening using passive cavitation detection with magnetic resonance imaging

    E-Print Network [OSTI]

    Konofagou, Elisa E.

    cavitation detection with magnetic resonance imaging validation Tao Sun1 , Gesthimani Samiotaki1 and Elisa E (diameters: 1-2, 4-5, or 6-8 m). A 10-MHz passive cavitation detector was used to acquire cavitation signals that the stable cavitation dose increased with the number of days required for closing while it reached a plateau

  12. Lamellar thickness and stretching temperature dependency of cavitation in semicrystalline polymers

    E-Print Network [OSTI]

    Yaotao Wang; Zhiyong Jiang; Lianlian Fu; Ying Lu; Yongfeng Men

    2014-05-13T23:59:59.000Z

    Polybutene-1 (PB-1), a typical semicrystalline polymer, in its stable form I shows a peculiar temperature dependent strain-whitening behavior when being stretched at different temperatures where the extent of strain-whitening weakens with the increasing of stretching temperature reaching a minima value followed by an increase at higher stretching temperatures. Correspondingly, a stronger strain-hardening phenomenon was observed at higher stretching temperatures. The strain-whitening phenomenon in semicrystalline polymers has its origin of cavitation process during stretching. In this work, the effect of crystalline lamellar thickness and stretching temperature on the cavitation process in PB-1 has been investigated by means of combined synchrotron ultrasmall-angle and wide-angle X-ray scattering techniques. It was found that, with respect to the cavitation process, three modes of cavitation during the stretching process can be identified, namely no cavitation for sample with the thinnest lamellae where only shear yielding occurred, cavitation with reorientation for the samples stretched at lower temperatures and samples with thicker lamellae, and cavitation without reorientation for samples with thinner lamellae stretched at higher temperatures. The mode cavitation with reorientation occurs before yield point where the plate-like cavities start to be generated within the lamellar stacks with normal perpendicular to the stretching direction due to the blocky substructure of the crystalline lamellae and reorient gradually to the stretching direction after strain-hardening. The mode of cavitation without reorientation appears after yield point where ellipsoidal shaped cavities are generated in those lamellae stacks with normal parallel to the stretching direction followed by an improvement of their orientation at larger strains.

  13. Bulk Viscosity and Cavitation in Boost-Invariant Hydrodynamic Expansion

    E-Print Network [OSTI]

    Krishna Rajagopal; Nilesh Tripuraneni

    2010-02-16T23:59:59.000Z

    We solve second order relativistic hydrodynamics equations for a boost-invariant 1+1-dimensional expanding fluid with an equation of state taken from lattice calculations of the thermodynamics of strongly coupled quark-gluon plasma. We investigate the dependence of the energy density as a function of proper time on the values of the shear viscosity, the bulk viscosity, and second order coefficients, confirming that large changes in the values of the latter have negligible effects. Varying the shear viscosity between zero and a few times s/(4 pi), with s the entropy density, has significant effects, as expected based on other studies. Introducing a nonzero bulk viscosity also has significant effects. In fact, if the bulk viscosity peaks near the crossover temperature Tc to the degree indicated by recent lattice calculations in QCD without quarks, it can make the fluid cavitate -- falling apart into droplets. It is interesting to see a hydrodynamic calculation predicting its own breakdown, via cavitation, at the temperatures where hadronization is thought to occur in ultrarelativistic heavy ion collisions.

  14. Cavitation controlled acoustic probe for fabric spot cleaning and moisture monitoring

    DOE Patents [OSTI]

    Sheen, Shuh-Haw (Naperville, IL); Chien, Hual-Te (Naperville, IL); Raptis, Apostolos C. (Downers Grove, IL)

    1997-01-01T23:59:59.000Z

    A method and apparatus are provided for monitoring a fabric. An acoustic probe generates acoustic waves relative to the fabric. An acoustic sensor, such as an accelerometer is coupled to the acoustic probe for generating a signal representative of cavitation activity in the fabric. The generated cavitation activity representative signal is processed to indicate moisture content of the fabric. A feature of the invention is a feedback control signal is generated responsive to the generated cavitation activity representative signal. The feedback control signal can be used to control the energy level of the generated acoustic waves and to control the application of a cleaning solution to the fabric.

  15. The Significance of Cavitation in a Superplastic Aluminum Alloy Processed by ECAP

    E-Print Network [OSTI]

    Southern California, University of

    The Significance of Cavitation in a Superplastic Aluminum Alloy Processed by ECAP Megumi Kawasaki spray-cast aluminum 7034 alloy having an initial grain size of ~2.1 m to produce an ultrafine grain size

  16. Program gives design data for multiple-orifice system to avoid cavitation

    SciTech Connect (OSTI)

    Coksem, P.G.; Patel, I.D.

    1985-04-15T23:59:59.000Z

    Determining the sizes of and axial distances between orifices in a multiple-orifice system is addressed in this HP-41CV program. Accurate measurements of these parameters are critical to avoid cavitation.

  17. Implicit Large Eddy Simulation of Cavitation in Micro Channel Flows

    E-Print Network [OSTI]

    Hickel, S; Schmidt, S J

    2014-01-01T23:59:59.000Z

    We present a numerical method for Large Eddy Simulations (LES) of compressible two-phase flows. The method is validated for the flow in a micro channel with a step-like restriction. This setup is representative for typical cavitating multi-phase flows in fuel injectors and follows an experimental study of Iben et al., 2010. While a diesel-like test fuel was used in the experiment, we solve the compressible Navier-Stokes equations with a barotropic equation of state for water and vapor and a simple phase-change model based on equilibrium assumptions. Our LES resolve all wave dynamics in the compressible fluid and the turbulence production in shear layers.

  18. Large-eddy simulation of turbulent cavitating flow in a micro channel

    SciTech Connect (OSTI)

    Egerer, Christian P., E-mail: christian.egerer@aer.mw.tum.de; Hickel, Stefan; Schmidt, Steffen J.; Adams, Nikolaus A. [Institute of Aerodynamics and Fluid Mechanics, Technische Universitt Mnchen, Boltzmannstr. 15, 85748 Garching bei Mnchen (Germany)

    2014-08-15T23:59:59.000Z

    Large-eddy simulations (LES) of cavitating flow of a Diesel-fuel-like fluid in a generic throttle geometry are presented. Two-phase regions are modeled by a parameter-free thermodynamic equilibrium mixture model, and compressibility of the liquid and the liquid-vapor mixture is taken into account. The Adaptive Local Deconvolution Method (ALDM), adapted for cavitating flows, is employed for discretizing the convective terms of the Navier-Stokes equations for the homogeneous mixture. ALDM is a finite-volume-based implicit LES approach that merges physically motivated turbulence modeling and numerical discretization. Validation of the numerical method is performed for a cavitating turbulent mixing layer. Comparisons with experimental data of the throttle flow at two different operating conditions are presented. The LES with the employed cavitation modeling predicts relevant flow and cavitation features accurately within the uncertainty range of the experiment. The turbulence structure of the flow is further analyzed with an emphasis on the interaction between cavitation and coherent motion, and on the statistically averaged-flow evolution.

  19. Effect of cavitation on the properties of coal-tar pitch as studied by gas-liquid chromatography

    SciTech Connect (OSTI)

    M.I. Baikenov; T.B. Omarbekov; S.K. Amerkhanova (and others) [Buketov State University, Karaganda (Kazakhstan)

    2008-02-15T23:59:59.000Z

    The applicability of the cavitation-wave effect to coal-tar pitch processing is considered. The results of the GLC analysis of the test material before and after rotor-pulsation cavitation treatment are given. The organic matter of coal-tar pitch was found to degrade upon cavitation; as a result of this, the yields of light and medium fractions considerably increased. 5 refs., 2 figs., 4 tabs.

  20. HYPOTHSES SUR L'ORIGINE DES BRUITS DU COEUR ET DES ACCIDENTS DE DCOMPRESSION EN PLONGE : LA CAVITATION.

    E-Print Network [OSTI]

    CAVITATION. HYPOTH?SE SUR L'ORIGINE DE LA FERMETURE DES VALVES CARDIAQUES : LE PH?NOM?NE DE VENTOUSE. Dr. R'un phénomène de cavitation à l'origine des bruits de Korotkoff. Encouragés par l'aphorisme de MacDonald comme quoi le phénomène de cavitation est plus fréquent qu'on peut le penser dans le système cardio

  1. LA CAVITATION A L'ORIGINE DES BRUITS DU COEUR ET DES ACCIDENTS DE DCOMPRESSION EN PLONGE.

    E-Print Network [OSTI]

    1 LA CAVITATION A L'ORIGINE DES BRUITS DU COEUR ET DES ACCIDENTS DE D?COMPRESSION EN PLONG?E. R'un phénomène de cavitation à l'origine des bruits de Korotkoff. Encouragés par l'aphorisme de MacDonald comme quoi le phénomène de cavitation est plus fréquent qu'on peut le penser dans le système cardio

  2. Correlation between simulations and cavitation-induced erosion damage in Spallation Neutron Source target modules after operation

    SciTech Connect (OSTI)

    Riemer, Bernie [ORNL] [ORNL; McClintock, David A [ORNL] [ORNL; Kaminskas, Saulius [ORNL] [ORNL; Abdou, Ashraf A [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    An explicit finite element (FE) technique developed for estimating dynamic strain in the Spallation Neutron Source (SNS) mercury target module vessel is now providing insight into cavitation damage patterns observed in used targets. The technique uses an empirically developed material model for the mercury that describes liquid-like volumetric stiffness combined with a tensile pressure cut-off limit that approximates cavitation. The longest period each point in the mercury is at the tensile cut-off threshold is denoted its saturation time. Now, the pattern of saturation time can be obtained from these simulations and is being positively correlated with observed damage patterns and is interpreted as a qualitative measure of damage potential. Saturation time has been advocated by collaborators at J-Parc as a factor in predicting bubble nuclei growth and collapse intensity. The larger the ratio of maximum bubble size to nucleus, the greater the bubble collapse intensity to be expected; longer saturation times result in greater ratios. With the recent development of a user subroutine for the FE solver saturation time is now provided over the entire mercury domain. Its pattern agrees with spots of damage seen above and below the beam axis on the SNS inner vessel beam window and elsewhere. The other simulation result being compared to observed damage patterns is mercury velocity at the wall. Related R&D has provided evidence for the damage mitigation that higher wall velocity provides. In comparison to observations in SNS targets, inverse correlation of high velocity to damage is seen. In effect, it is the combination of the patterns of saturation time and low velocity that seems to match actual damage patterns.

  3. To cite this document: Duplaa, Sbastien and Coutier-Delgosha, Olivier and Dazin, Antoine and Bois, Grard and Caignaert, Guy and Roussette, Olivier Cavitation inception

    E-Print Network [OSTI]

    Boyer, Edmond

    , Gérard and Caignaert, Guy and Roussette, Olivier Cavitation inception in fast startup. (2008) In-Hawaii : United States (2008)" #12;1 CAVITATION INCEPTION IN FAST STARTUP S. Duplaa1 , O. Coutier-Delgosha1 , A in partial flow vaporization, i.e. cavitation. An existing experimental test rig has been updated in the LML

  4. Real-time prediction of the reversibility of the ultrasound-induced blood-brain barrier opening using passive cavitation detection with MRI validation

    E-Print Network [OSTI]

    Konofagou, Elisa E.

    using passive cavitation detection with MRI validation Tao Sun1 , Gesthimani Samiotaki1 and Elisa E, represented by the cavitation dose, as monitored during BBB opening to the reversibility of BBB opening). A single-element, pulse-echo ultrasound transducer served as a passive cavitation detector was used

  5. Cavitation in elastomeric solids: I--A defect-growth theory Oscar Lopez-Pamies a,, Martin I. Idiart b,c

    E-Print Network [OSTI]

    Nakamura, Toshio

    Cavitation in elastomeric solids: I--A defect-growth theory Oscar Lopez-Pamies a,?, Marti´n I. The occurrence of such instabilities, commonly referred to as cavitation, can be attributed to the growth of pre-existing defects into finite sizes. This paper introduces a new theory to study the phenomenon of cavitation

  6. Combination of thermal and cavitation effects to generate deep lesions with an endocavitary applicator using a plane transducer: Ex vivo studies.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Combination of thermal and cavitation effects to generate deep lesions with an endocavitary@lyon.inserm.fr Running title : Combination of thermal and cavitation effects inserm-00189856,version1-22Nov2007 Author.ultrasmedbio.2003.09.005 #12;2 Combination of thermal and cavitation effects to generate deep lesions

  7. A mixture-energy-consistent six-equation two-phase numerical model for fluids with interfaces, cavitation and evaporation waves

    E-Print Network [OSTI]

    Pelanti, Marica

    , cavitation and evaporation waves Marica Pelantia, , Keh-Ming Shyueb aDepartment of Mechanical Engineering, Taiwan. Abstract We model liquid-gas flows with cavitation by a variant of the six-equation single cavitation mechanisms and evaporation wave dynamics. Keywords: multiphase compressible flow models

  8. An Application of Chaos Theory for Estimation of Simultaneous Variability of RR-intervals in Heart and Systolic Blood Pressure in Humans

    E-Print Network [OSTI]

    Elio Conte; Antonio Federici; Joseph P. Zbilut

    2008-10-22T23:59:59.000Z

    We introduce a new method to estimate BaroReflex Sensitivity (BRS) . The methodology, based on the CZF formulation, recently published (see Conte et al 2008), enables to evaluate simultaneous variability of RR and SBP and to estimate the coupling strength. The technique is applied to subjects (female and men with age ranging from 21 to 28 years old) and it is compared with the results that may be obtained by using the standard Fourier spectral analysis technique. The comparison is also performed by using the technique of Lomb-Scargle periodogram, based on Fourier analysis.

  9. Cavitation regime detection through Proper Orthogonal Decomposition: dynamics analysis of the sheet cavity on a grooved convergent-divergent nozzle

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Cavitation regime detection through Proper Orthogonal Decomposition: dynamics analysis of the sheet in turbines and propellers is responsible for many issues like erosion, noise and vibrations. This two). This method is applied to sequences of sheet cavity images, in order to identify the cavitation regimes (sheet

  10. JOURNAL OF MICROELECTROMECHANICAL SYSTEMS, VOL. 15, NO. 5, OCTOBER 2006 1319 Development of Cavitation in Refrigerant (R-123)

    E-Print Network [OSTI]

    Peles, Yoav

    of Cavitation in Refrigerant (R-123) Flow Inside Rudimentary Microfluidic Systems Chandan Mishra and Yoav Peles Abstract--The existence of hydrodynamic cavitation in the flow of refrigerant (R-123) through micro patterns observed in refrigerant (R-123) and water flows through a micro-Venturi system. [1575] Index Terms

  11. To appear in the International Journal of Fracture Cavitation in Rubber: An Elastic Instability or a Fracture Phenomenon?

    E-Print Network [OSTI]

    Lopez-Pamies, Oscar

    To appear in the International Journal of Fracture Cavitation in Rubber: An Elastic Instability that cavitation in rubber -- that is, the sudden growth of inherent defects in rubber into large enclosed cavities far exceed the elastic limit of the rubber, which therefore ought to inelastically deform

  12. Mathematical model of cavitation during resin lm infusion process I. Sevostianov a,*, V.E. Verijenko b

    E-Print Network [OSTI]

    Sevostianov, Igor

    Mathematical model of cavitation during resin lm infusion process I. Sevostianov a,*, V lm infusion (RFI) process. An analytical model is developed to describe the cavitation conditions formation; Resin lm infusion 1. Introduction The resin lm infusion (RFI) method of producing composite

  13. DNS and LES of two-phase flows with cavitation

    E-Print Network [OSTI]

    Hickel, Stefan

    2014-01-01T23:59:59.000Z

    We report on recent progress in the physical and numerical modeling of compressible two-phase flows that involve phase transition between the liquid and gaseous state of the fluid. The high-speed dynamics of cavitation bubbles is studied in well-resolved simulations (DNS) with a sharp-interface numerical model on a micro scale. The underlying assumption of the employed evaporation/condensation model is that phase change occurs in thermal non-equilibrium and that the associated timescale is larger than that of the wave dynamics. Results for the collapse of a spherical vapor bubble close to a solid wall are discussed for three different bubble-wall configurations. The major challenge for such numerical investigations is to accurately reproduce the dynamics of the interface between liquid and vapor during the entire collapse process, including the high-speed dynamics of the late stages, where compressibility of both phases plays a decisive role. Direct interface resolving simulations are intractable for real wor...

  14. The effect of tungsten and molybdenum additions on the cavitation corrosion behavior of duplex stainless steel (DSS) in seawater

    SciTech Connect (OSTI)

    Al-Hashem, A.; Abdullah, A.; Shalaby, H.M. [Kuwait Inst. for Scientific Research, Safat (Kuwait). Materials Application Dept.

    1998-12-31T23:59:59.000Z

    Cavitation corrosion studies were conducted on two duplex stainless steel (DSS) specimens of which one was containing tungsten and more molybdenum than the other. Experiments were conducted in seawater using an ultrasonically-induced cavitation facilities. The rate of mass-loss, free corrosion potential, and microscopic examinations were compared for the two alloys in the presence and absence of cavitation. There was negligible mass loss for the two alloys under stagnant conditions. However, some differences were observed between the two alloys with respect to mass-loss, corrosion potential and morphology of attacked areas. The alloy containing tungsten and mover molybdenum experienced more loss in weight regardless of their more noble corrosion potential during cavitation. This difference in behavior was explained in terms of the effect of the alloying elements on the microstructure of the alloys and their susceptibility to absorb the impact energy of cavitation.

  15. Measurement of the thorium-228 activity in solutions cavitated by ultrasonic sound

    E-Print Network [OSTI]

    R. Ford; M. Gerbier-Violleau; E. Vazquez-Jauregui

    2009-11-10T23:59:59.000Z

    We show that cavitation of a solution of thorium-228 in water does not induce its transformation at a faster rate than the natural radioactive decay. We measured the activity of a thorium-228 solution in water before, and after, it was subjected to a cavitation at 44 kHz and $250 $W for 90 minutes in order to observe any change in the thorium half-life. The results were compared to the original activity of the sample and we observed no change. Our results and conclusions conflict with those in a recent paper by F. Cardone et. al. [Phys. Lett. A 373 (2009) 1956-1958].

  16. acoustic cavitation bubble: Topics by E-print Network

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

    G. Simon; M. T. Levinsen 2002-09-11 204 Analytical and experimental investigations of gas turbine model combustor acoustics operated at atmospheric pressure Physics Websites...

  17. Electron acceleration in cavitated laser produced ion channels

    SciTech Connect (OSTI)

    Naseri, N. [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada) [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Tech-X Corporation, Boulder, Colorado 80303 (United States); Pesme, D. [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada) [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Centre de Physique Thorique, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Rozmus, W. [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada)] [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada)

    2013-10-15T23:59:59.000Z

    This paper is concerned with the channeling of a relativistic laser pulse in an underdense plasma and with the subsequent generation of fast electrons in the cavitated ion channel. The laser pulse has a duration of several hundreds of femtoseconds and its power P{sub L} exceeds the critical power for laser channeling P{sub ch}, with P{sub ch}?1.1P{sub c}, P{sub c} denoting the critical power for relativistic self-focusing. The laser pulse is focused in a plasma of electron density n{sub 0} such that the ratio n{sub 0}/n{sub c} lies in the interval [10{sup ?3},10{sup ?1}], n{sub c} denoting the critical density. The laser-plasma interaction under such conditions is investigated by means of three dimensional Particle-In-Cell (PIC) simulations. It is observed that the steep laser front gives rise to the excitation of a surface wave which propagates along the sharp radial boundaries of the electron free channel created by the laser pulse. The mechanism responsible for the generation of relativistic electrons observed in the PIC simulations is also analyzed by means of a test particles code. The fast electrons are found to be generated by the combination of a surface wave and of the betatron resonance. The maximum electron energy observed in the simulations is scaled as a function of P{sub L}/P{sub c}; it reaches 350600 MeV for P{sub L}/P{sub c} = 70140.

  18. Numerical study of expansion tube problems: toward the simulation of cavitation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    .11.019 #12;diminution of the speed of sound in the mixture), large density ratio be- tween the liquid-phase flow models. This method makes no attempt to track the liquid and vapour interface. As most two for inviscid high-speed cavitating applications and two-phase Riemann problems [2, 3, 4, 5]. For thermal- 2 hal

  19. Acoustically driven cavitation cluster collapse in planar geometry Ivan van der Kroon,1

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    the dynamics of arrays of transient cavitation bubbles exposed to a sound field in a planar geometry. Single with a digital hologram and focusing it into a thin gap of liquid. The liquid is driven with an oscillating with high-speed photography with a two-dimensional Rayleigh model. For multibubble configura- tions we

  20. INVESTIGATION OF A NEW MODEL FOR BUBBLY CAVITATING FLOW Tim Colonius

    E-Print Network [OSTI]

    Colonius, Tim

    account for phase change, liquid compressibility, and heat and mass transfer within the bubble contents [3 of these models, two-way coupled (dynamic) effects of cavitation are considered meaning that the time evolution], but existing phase- and volume-averaging approaches require two fundamental assumptions that limit

  1. 1 Copyright 1999 by ASME MULTI-PHASE CFD ANALYSIS OF NATURAL AND VENTILATED CAVITATION

    E-Print Network [OSTI]

    Kunz, Robert Francis

    volume fraction transport/generation for liquid, condensable vapor and non-con- densable gas fields between condensable vapor and non-condensable gas, a requirement of our current applica- tion. By solving1 Copyright © 1999 by ASME MULTI-PHASE CFD ANALYSIS OF NATURAL AND VENTILATED CAVITATION ABOUT

  2. HYPOTHSES SUR L'ORIGINE DES BRUITS DU COEUR ET DES ACCIDENTS DE DCOMPRESSION EN PLONGE : LA CAVITATION.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    CAVITATION. HYPOTH?SE SUR L'ORIGINE DE LA FERMETURE DES VALVES CARDIAQUES : LE RETARD ? LA FERMETURE DES un travail antérieur, l'hypothèse d'un phénomène de cavitation à l'origine des bruits de Korotkoff. Encouragés par l'aphorisme de MacDonald comme quoi le phénomène de cavitation est plus fréquent qu'on peut le

  3. Influence of Heat Treatment on Mercury Cavitation Resistance of Surface Hardened 316LN Stainless Steel

    SciTech Connect (OSTI)

    Pawel, Steven J [ORNL; Hsu, Julia [Massachusetts Institute of Technology (MIT)

    2010-11-01T23:59:59.000Z

    The cavitation-erosion resistance of carburized 316LN stainless steel was significantly degraded but not destroyed by heat treatment in the temperature range 500-800 C. The heat treatments caused rejection of some carbon from the carburized layer into an amorphous film that formed on each specimen surface. Further, the heat treatments encouraged carbide precipitation and reduced hardness within the carburized layer, but the overall change did not reduce surface hardness fully to the level of untreated material. Heat treatments as short as 10 min at 650 C substantially reduced cavitation-erosion resistance in mercury, while heat treatments at 500 and 800 C were found to be somewhat less detrimental. Overall, the results suggest that modest thermal excursions perhaps the result of a weld made at some distance to the carburized material or a brief stress relief treatment will not render the hardened layer completely ineffective but should be avoided to the greatest extent possible.

  4. Evaluation of Cavitation-Erosion Resistance of 316LN Stainless Steel in Mercury Containing Metallic Solutes

    SciTech Connect (OSTI)

    Pawel, Steven J [ORNL; Mansur, Louis K [ORNL

    2006-08-01T23:59:59.000Z

    Room temperature cavitation tests of vacuum annealed type 316LN stainless steel were performed in pure Hg and in Hg with various amounts of metallic solute to evaluate potential mitigation of erosion/wastage. Tests were performed using an ultrasonic vibratory horn with specimens attached at the tip. All of the solutes examined, which included 5 wt% In, 10 wt% In, 4.4 wt% Cd, 2 wt% Ga, and a mixture that included 1 wt% each of Pb, Sn, and Zn, were found to increase cavitation-erosion as measured by increased weight loss and/or surface profile development compared to exposures for the same conditions in pure Hg. Qualitatively, each solute appeared to increase the post-test wetting tenacity of the Hg solutions and render the Hg mixture susceptible to manipulation of droplet shape.

  5. The resistance to cavitation erosion of CrMnN stainless steels

    SciTech Connect (OSTI)

    Fu, W.T. [Yanshan Univ., Qinhuangdao (China). Dept. of Materials Engineering] [Yanshan Univ., Qinhuangdao (China). Dept. of Materials Engineering; [Harbin Inst. of Tech. (China); Jing, T.F.; Zheng, Y.Z. [Yanshan Univ., Qinhuangdao (China). Dept. of Materials Engineering] [Yanshan Univ., Qinhuangdao (China). Dept. of Materials Engineering; Yang, Y.B. [Yanshan Univ., Qinhuangdao (China). Dept. of Materials Engineering] [Yanshan Univ., Qinhuangdao (China). Dept. of Materials Engineering; [Bohai Aluminum Industries Co., Ltd., Qinhuangdao (China); Yao, M. [Harbin Inst. of Tech. (China)] [Harbin Inst. of Tech. (China)

    1998-12-01T23:59:59.000Z

    The resistance to cavitation erosion (CE) was measured using a magnetostrictive device and a rotating disk device for some CrMnN stainless steels (Chinese patent ZL 90 1 02197.0). The microstructural changes in the surface layer before and after CE were analyzed by use of Mossbauer spectra. Results show that the resistance to CE of duplex austenitic-martensitic CrMnN stainless steels is much better than that of ZG0Cr13Ni4-6Mo and ZG0Cr16Ni5Mo steel, which are in common use for hydraulic turbine runners. The metastable austenite and its changes in the process of CE are the key factors why the CrMnN stainless steels have excellent resistance to cavitation erosion.

  6. Effect of temperature and strain rate on cavitation in a superplastic duplex stainless steel

    SciTech Connect (OSTI)

    Pulino-Sagradi, D.; Nazar, A.M.M.; Ammann, J.J.; Medrano, R.E. [State Univ. of Campinas, Sao Paulo (Brazil). Dept. of Materials Engineering] [State Univ. of Campinas, Sao Paulo (Brazil). Dept. of Materials Engineering

    1997-11-01T23:59:59.000Z

    The effect of temperature and strain rate on cavitation during superplastic deformation of a duplex stainless steel has been studied at 1,223 K and 1,253 K for initial strain rates ranging from 2 {times} 10{sup {minus}4} s{sup {minus}1} to 2 {times} 10{sup {minus}3} s{sup {minus}1}. The cavitation was analyzed quantitatively for a specifically developed image processing technique that allows an accurate determination of the volume fraction and size distribution of the voids. The results show that increasing temperature and/or decreasing strain rate cause a more homogeneous deformation of the specimen characterized by a uniform size and distribution of the cavities. The increase of the strain rate results in an increase in cavity volume fraction related to more cavity nucleation and interlinkage. This reflects the lack of accommodation process during the mechanism of grain boundary sliding.

  7. Cavitation nanopore in the dielectric fluid in the inhomogeneous, pulsed electric fields

    E-Print Network [OSTI]

    Pekker, M

    2014-01-01T23:59:59.000Z

    This paper discusses the nanopores emerging and developing in a liquid dielectric under the action of the ponderomotive electrostrictive forces in a nonuniform electric field. It is shown that the gradient of the electric field in the vicinity of the rupture (cavitation nanopore) substantially increases and determines whether the rupture grows or collapses. The cavitation rupture in the liquid (nanopore) tends to stretch along the lines of the original field. The mechanism of the breakdown associated with the generation of secondary ruptures in the vicinity of the poles of the nanopore is proposed. The estimations of the extension time for nanopore in water and oil (polar and nonpolar liquids, respectively) are presented. A new mechanism of nano- and subnanosecond breakdown in the insulating (transformer) oil that can be realized in the vicinity of water microdroplets in modern nanosecond high-voltage devices is considered

  8. A unified electrostatic and cavitation model for first-principles molecular dynamics in solution

    E-Print Network [OSTI]

    Damian A. Scherlis; Jean-Luc Fattebert; Francois Gygi; Matteo Cococcioni; Nicola Marzari

    2005-10-06T23:59:59.000Z

    The electrostatic continuum solvent model developed by Fattebert and Gygi is combined with a first-principles formulation of the cavitation energy based on a natural quantum-mechanical definition for the surface of a solute. Despite its simplicity, the cavitation contribution calculated by this approach is found to be in remarkable agreement with that obtained by more complex algorithms relying on a large set of parameters. Our model allows for very efficient Car-Parrinello simulations of finite or extended systems in solution, and demonstrates a level of accuracy as good as that of established quantum-chemistry continuum solvent methods. We apply this approach to the study of tetracyanoethylene dimers in dichloromethane, providing valuable structural and dynamical insights on the dimerization phenomenon.

  9. Cavitation nanopore in the dielectric fluid in the inhomogeneous, pulsed electric fields

    E-Print Network [OSTI]

    M. Pekker; M. N. Shneider

    2014-12-19T23:59:59.000Z

    This paper discusses the nanopores emerging and developing in a liquid dielectric under the action of the ponderomotive electrostrictive forces in a nonuniform electric field. It is shown that the gradient of the electric field in the vicinity of the rupture (cavitation nanopore) substantially increases and determines whether the rupture grows or collapses. The cavitation rupture in the liquid (nanopore) tends to stretch along the lines of the original field. The mechanism of the breakdown associated with the generation of secondary ruptures in the vicinity of the poles of the nanopore is proposed. The estimations of the extension time for nanopore in water and oil (polar and nonpolar liquids, respectively) are presented. A new mechanism of nano- and subnanosecond breakdown in the insulating (transformer) oil that can be realized in the vicinity of water microdroplets in modern nanosecond high-voltage devices is considered

  10. VOLUME 84, NUMBER 4 P H Y S I C A L R E V I E W L E T T E R S 24 JANUARY 2000 Effect of Noble Gases on Sonoluminescence Temperatures during Multibubble Cavitation

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    on Sonoluminescence Temperatures during Multibubble Cavitation Yuri T. Didenko, William B. McNamara III, and Kenneth S atoms serves as an internal thermome- ter of cavitation. The intensity and temperature occur during acoustic cavitation [1,2]. This highly nonlinear bubble motion is accompanied

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

    DOE Patents [OSTI]

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

    1990-01-01T23:59:59.000Z

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

  12. Cavitation in a metallic liquid: Homogeneous nucleation and growth of nanovoids

    SciTech Connect (OSTI)

    Cai, Y. [Department of Modern Mechanics, CAS Key Laboratory of Materials Behavior and Design, University of Science and Technology of China, Hefei, Anhui 230027 (China); The Peac Institute of Multiscale Sciences, Chengdu, Sichuan 610207 (China); Wu, H. A., E-mail: wuha@ustc.edu.cn [Department of Modern Mechanics, CAS Key Laboratory of Materials Behavior and Design, University of Science and Technology of China, Hefei, Anhui 230027 (China); Luo, S. N., E-mail: sluo@pims.ac.cn [The Peac Institute of Multiscale Sciences, Chengdu, Sichuan 610207 (China)

    2014-06-07T23:59:59.000Z

    Large-scale molecular dynamics (MD) simulations are performed to investigate homogeneous nucleation and growth of nanovoids during cavitation in liquid Cu. We characterize in detail the atomistic cavitation processes by following the temporal evolution of cavities or voids, analyze the nucleation behavior with the mean first-passage time (MFPT) and survival probability (SP) methods, and discuss the results against classical nucleation theory (CNT), the Tolman equation for surface energy, independent calculation of surface tension via integrating the stress profiles, the Johnson-Mehl-Avrami (JMA) growth law, and the power law for nucleus size distributions. Cavitation in this representative metallic liquid is a high energy barrier Poisson processes, and the steady-state nucleation rates obtained from statistical runs with the MFPT and SP methods are in agreement. The MFPT method also yields the critical nucleus size and the Zeldovich factor. Fitting with the Tolman's equation to the MD simulations yields the surface energy of a planar interface (?0.9 Jm{sup ?2}) and the Tolman length (0.40.5 ), and those values are in accord with those from integrating the stress profiles of a planar interface. Independent CNT predictions of the nucleation rate (10{sup 33?34} s{sup ?1}m{sup ?3}) and critical size (34 in radius) are in agreement with the MFPT and SP results. The JMA law can reasonably describe the nucleation and growth process. The size distribution of subcritical nuclei appears to follow a power law with an exponent decreasing with increasing tension owing to coupled nucleation and growth, and that of the supercritical nuclei becomes flattened during further stress relaxation due to void coalescence.

  13. Feasibility study of tuned-resonator, pulsating cavitating water jet for deep-hole drilling

    SciTech Connect (OSTI)

    Johnson, V.E. Jr.; Lindenmuth, W.T.; Conn, A.F.; Frederick, G.S.

    1981-08-01T23:59:59.000Z

    This study presents the advantages of pulsing a submerged jet to increase its erosion capability (particularly as caused by cavitation) in augmenting deep-hole drill bits. Various methods of accomplishing the pulsation are presented and discussed. The most attractive systems uncovered are acoustic oscillators which passively accomplish pulsations in the flow at frequencies corresponding to a Strouhal number in the range of 0.2 to 1.0. Such passive oscillators are assessed to be feasible candidates for development into practical deep hole drill bit systems and a long range plan for this research and development is presented and discussed.

  14. Title: Combined passive detection and ultrafast active imaging of cavitation events induced by short pulses of high intensity

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Title: Combined passive detection and ultrafast active imaging of cavitation events induced by short pulses of high intensity ultrasound Authors: Jérôme GATEAU, Jean-François AUBRY, Mathieu PERNOT / INSERM, U979 / Université Denis Diderot, Paris VII Key words: single nucleation events, ultrafast active

  15. Dynamics of cavitation bubble induced by 193 nm ArF excimer laser in concentrated sodium chloride solutions

    E-Print Network [OSTI]

    Palanker, Daniel

    of pulsed lasers for ablation, drilling, and cutting of soft tissues in liquid environments are accompaniedDynamics of cavitation bubble induced by 193 nm ArF excimer laser in concentrated sodium chloride solutions Igor Turovets and Daniel Palanker Laser Center, Hadassah University Hospital, P.O. Box 12000

  16. Impacts of Static Pressure Reset on VAV System Air Leakage, Fan Power and Thermal Energy - Part I: Theoretical Model and Simulation

    E-Print Network [OSTI]

    Liu, M.; Feng, J.; Wang, Z.; Wu, L.; Zheng, K.; Pang, W.

    2007-01-01T23:59:59.000Z

    As for a variable air volume (VAV) system, the air duct static pressure is a typical control variable maintained by modulating supply fan speed. The static pressure equals to the summation of the duct pressure loss downstream of the sensor...

  17. Cataclysmic Variables

    E-Print Network [OSTI]

    Robert Connon Smith

    2007-01-23T23:59:59.000Z

    Cataclysmic variables are binary stars in which a relatively normal star is transferring mass to its compact companion. This interaction gives rise to a rich range of behaviour, of which the most noticeable are the outbursts that give the class its name. Novae belong to the class, as do the less well known dwarf novae and magnetic systems. Novae draw their energy from nuclear reactions, while dwarf novae rely on gravity to power their smaller eruptions. All the different classes of cataclysmic variable can be accommodated within a single framework and this article will describe the framework, review the properties of the main types of system and discuss models of the outbursts and of the long-term evolution.

  18. Manipulation and Microrheology of Carbon Nanotubes with Laser-Induced Cavitation Bubbles P. A. Quinto-Su, X. H. Huang, S. R. Gonzalez-Avila, T. Wu, and C. D. Ohl

    E-Print Network [OSTI]

    Ohl, Claus-Dieter

    Manipulation and Microrheology of Carbon Nanotubes with Laser-Induced Cavitation Bubbles P. A) Multiwalled carbon nanotubes (MWCNT) are exposed to a transient and strong liquid jet flow created by a pair of differently sized laser-induced cavitation bubbles. The position and size of the bubbles are controlled

  19. RESULTS FROM CAVITATION DAMAGE EXPERIMENTS WITH MERCURY SPALLATION TARGETS AT THE LANSCE WNR IN 2008

    SciTech Connect (OSTI)

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

    2010-01-01T23:59:59.000Z

    Damage assessment from proton beam induced cavitation experiments on mercury spallation targets done at the LANSCE WNR facility has been completed. The experiments investigated two key questions for the Spallation Neutron Source target, namely, how damage is affected by flow velocity in the SNS coolant channel geometry, and how damage scales with proton beam intensity at a given constant charge per pulse. With regard to the former question, prior in-beam experiments indicated that the coolant channel geometry with stagnant mercury was especially vulnerable to damage which might warrant a design change. Yet other results indicated a reduction in damage with the introduction of flow. Using more prototypic to the SNS, the 2008 experiment damage results show the channel is less vulnerable than the bulk mercury side of the vessel wall. They also show no benefit from increasing channel flow velocity beyond nominal SNS speeds. The second question probed a consensus belief that damage scales with beam intensity (protons per unit area) by a power law dependence with exponent of around 4. Results from a 2005 experiment did not support this power law dependence but some observations were inconsistent and unexplained. These latest results show weaker damage dependence.

  20. Effect of temperature and pH on cavitation erosion of super duplex stainless steel

    SciTech Connect (OSTI)

    Kwok, C.T.; Man, H.C.; Leung, L.K. [Hong Kong Polytechnic Univ., Kowloon (Hong Kong)

    1996-10-01T23:59:59.000Z

    Cavitation erosion characteristics of super duplex stainless steel (S32760) and austenitic stainless steel (S30400) in 3.5% NaCl solution with controlled temperature and pH value in the range of 10 to 70 C and pH 3 to 11 have been studied by means of a 20kHz ultrasonic vibrator at a peak to peak amplitude of 50 {micro}m. The erosion resistance of other stainless steels including S31803 and S31603 was also investigated for comparison purpose. Plots of cumulative erosion mass loss per unit area versus temperature for S32760 and S30400 indicate that the degree of erosion initially increases as the temperature increases from 10 C to 50 C and passes through a maximum at about 50 C and then decreases with further increase in temperature to 70 C. Results of cumulative erosion versus pH indicate that the degree of erosion of S32760 is more sensitive to pH value than that of S30400 at 23 C.

  1. Some new ideas for well log pore-pressure prediction

    SciTech Connect (OSTI)

    Hamouz, M.A.; Mueller, S.L.

    1984-09-01T23:59:59.000Z

    Predicting pore pressure from wireline logs is a common practice when designing wells. The accuracy of each prediction depends on the type of plot used and its associated assumptions. If these assumptions aren't adequately tested, then the results are often confusing and, possibly, dangerous. Accuracy is improved in all situations by plotting the correct wireline variables, checking the validity of the normal pressure trends with other pressure plots and regional data, and choosing the best techniques to estimate pressure.

  2. Cavitation in trees and the hydraulic sufficiency of woody Department of Botany, University of Vermont, Burlington, VT 05405, and Northeastern Forest Ex-

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Cavitation in trees and the hydraulic sufficiency of woody stems M. Tyree Department of Botany cycle of water stress leading to loss of hydraulic conductance and further dynamic stress (see Fig. 1 of hydraulic conductance in the stem. A loss of conductance means that sap will have to overcome a larger

  3. PressurePressure Indiana Coal Characteristics

    E-Print Network [OSTI]

    Fernndez-Juricic, Esteban

    TimeTime PressurePressure Indiana Coal Characteristics Indiana Coals for Coke CoalTransportation in Indiana Coal Slurry Ponds Evaluation Site Selection for Coal Gasification Coal-To-Liquids Study, CTL Indiana Coal Forecasting Under-Ground Coal Gasification Benefits of Oxyfuel Combustion Economic

  4. An experimental investigation of acoustic cavitation as a fragmentation mechanism of molten tin droplets in water

    E-Print Network [OSTI]

    Bjrnard, Trond Arnold

    1974-01-01T23:59:59.000Z

    A series of experiments were performed where single molten tin droplets of known size, shape and temperature were dropped from a low height into a pool of distilled water. The pressure waves emanating from the hot droplets ...

  5. Understanding Blood Pressure

    E-Print Network [OSTI]

    Understanding Blood Pressure Monitorathomewithadigitalmonitor. Useleftarmwithcorrectsizecuff. Avoidcaffeine,alcohol,andtobacco. Steps to Follow FOR AN ACCURATE MEASUREMENT Blood pressure is the measurement of the force of blood on the walls of the arteries. Bottom number = Diastolic (force between heart beats) Top

  6. A Variable Cell Model for Simulating Gas Condensate Reservoir Performance

    E-Print Network [OSTI]

    Al-Majed, Abdulaziz Abdullah

    maturation profiles, which ie exhibitpd when gas pressure. Between this region near tha wellbore, SPE-~~~ SPE 21428 A Variable Cell Model for Simulating Gas Condensate Reservoir Performance A of depletion performance of gas condensate reservoirs report the existence of a A variable cell model

  7. Atmospheric Pressure Reactor System | EMSL

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

    Atmospheric Pressure Reactor System Atmospheric Pressure Reactor System The atmospheric pressure reactor system is designed for testing the efficiency of various catalysts for the...

  8. Investigation of three-dimensional effects on a cavitating Venturi flow

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of the speed of sound in the mixture), large density ratio between the liquid and the vapour phases, small capacity at constant pressure cbaro Minimum speed of sound in the mixture CDES Constant of the DES model 2 dynamic eddy viscosity Mixture density sat L Density of liquid at saturation sat V Density of vapour

  9. TEXTURE-INDUCED CAVITATION BUBBLES AND FRICTION REDUCTION IN THE ELROD-ADAMS MODEL

    E-Print Network [OSTI]

    Buscaglia, Gustavo C.

    of an infinitely-wide pad, subject to a constant load and sliding at constant speed on a runner with transverseU function characterizing the pad profile 1 #12;m pad linear mass per unit width p hydrodynamic pressure width H non-dimensionalization length for z, Z and e R curvature radius of the pad's profile U non

  10. Pressure cryocooling protein crystals

    DOE Patents [OSTI]

    Kim, Chae Un (Ithaca, NY); Gruner, Sol M. (Ithaca, NY)

    2011-10-04T23:59:59.000Z

    Preparation of cryocooled protein crystal is provided by use of helium pressurizing and cryocooling to obtain cryocooled protein crystal allowing collection of high resolution data and by heavier noble gas (krypton or xenon) binding followed by helium pressurizing and cryocooling to obtain cryocooled protein crystal for collection of high resolution data and SAD phasing simultaneously. The helium pressurizing is carried out on crystal coated to prevent dehydration or on crystal grown in aqueous solution in a capillary.

  11. High temperature pressure gauge

    DOE Patents [OSTI]

    Echtler, J. Paul (Pittsburgh, PA); Scandrol, Roy O. (Library, PA)

    1981-01-01T23:59:59.000Z

    A high temperature pressure gauge comprising a pressure gauge positioned in fluid communication with one end of a conduit which has a diaphragm mounted in its other end. The conduit is filled with a low melting metal alloy above the diaphragm for a portion of its length with a high temperature fluid being positioned in the remaining length of the conduit and in the pressure gauge.

  12. Pressure-sensitive optrode

    DOE Patents [OSTI]

    Hirschfeld, T.B.

    1985-04-09T23:59:59.000Z

    An apparatus and method are disclosed for sensing changes in pressure and for generating optical signals related to changes in pressure. Light from a fiber optic is directed to a movable surface which is coated with a light-responsive material, and which moves relative to the end of the fiber optic in response to changes in pressure. The same fiber optic collects a portion of the reflected or emitted light from the movable surface. Changes in pressure are determined by measuring changes in the amount of light collected. 5 figs.

  13. Pressurized fluidized bed reactor

    DOE Patents [OSTI]

    Isaksson, Juhani (Karhula, FI)

    1996-01-01T23:59:59.000Z

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine.

  14. Pressurized fluidized bed reactor

    DOE Patents [OSTI]

    Isaksson, J.

    1996-03-19T23:59:59.000Z

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine. 1 fig.

  15. Dual shell pressure balanced vessel

    DOE Patents [OSTI]

    Fassbender, Alexander G. (West Richland, WA)

    1992-01-01T23:59:59.000Z

    A dual-wall pressure balanced vessel for processing high viscosity slurries at high temperatures and pressures having an outer pressure vessel and an inner vessel with an annular space between the vessels pressurized at a pressure slightly less than or equivalent to the pressure within the inner vessel.

  16. Testing of a variable-stroke Stirling engine

    SciTech Connect (OSTI)

    Thieme, L.G.; Allen, D.J.

    1986-01-01T23:59:59.000Z

    Testing of a variable-stroke Stirling engine at NASA Lewis has been completed. In support of the US Department of Energy's Stirling Engine Highway Vehicle Systems Program, the engine was tested for about 70 hr total with both helium and hydrogen working fluids over a range of pressures and strokes. A direct comparison was made of part-load efficiencies obtained with variable-stroke and variable-pressure operation. Two failures with the variable-angle swash-plate drive system limited testing to low power levels. These failures are not thought to be caused by problems inherent in the variable-stroke concept but they do emphasize the need for careful design in the area of the crossheads where the failures occurred. This paper describes these failures and the efforts to resolve the associated problems, and presents test results that were obtained. 5 refs., 17 figs.

  17. PRESSURE ACTIVATED SEALANT TECHNOLOGY

    SciTech Connect (OSTI)

    Michael A. Romano

    2004-04-01T23:59:59.000Z

    The objective of this project is to develop new, efficient, cost effective methods of internally sealing natural gas pipeline leaks through the application of differential pressure activated sealants. In researching the current state of the art for gas pipeline sealing technologies we concluded that if the project was successful, it appeared that pressure activated sealant technology would provide a cost effective alternative to existing pipeline repair technology. From our analysis of current field data for a 13 year period from 1985 to 1997 we were able to identify 205 leaks that were candidates for pressure activated sealant technology, affirming that pressure activated sealant technology is a viable option to traditional external leak repairs. The data collected included types of defects, areas of defects, pipe sizes and materials, incident and operating pressures, ability of pipeline to be pigged and corrosion states. This data, and subsequent analysis, was utilized as a basis for constructing applicable sealant test modeling.

  18. High pressure melt ejection

    SciTech Connect (OSTI)

    Tarbell, W.W.; Brockmann, J.E.; Pilch, M.

    1983-01-01T23:59:59.000Z

    Recent probabilistic risk assessments have identified the potential for reactor pressure vessel failure while the reactor coolant system is at elevated pressure. The analyses postulate that the blowdown of steam and hydrogen into the reactor cavity will cause the core material to be swept from the cavity region into the containment building. The High Pressure Melt Streaming (HIPS) program is an experimental study of the high pressure ejection of molten material and subsequent interactions within a concrete cavity. The program focuses on using prototypic system conditions and scaled models of reactor geometries to accurately simulate the ex-vessel processes during high-pressure accident sequences. Scaling analyses of the experiment show that the criteria established for core debris removal from the cavity are met or exceeded. Tests are performed at two scales, representing 1/10th and 1/20th linear reproductions of the Zion reactor plant. Results of the 1/20th scale tests are presented.

  19. Numerical Simulation of Flow Field Inside a Squeeze Film Damper and the Study of the Effect of Cavitation on the Pressure Distribution

    E-Print Network [OSTI]

    Khandare, Milind Nandkumar

    2012-02-14T23:59:59.000Z

    Squeeze Film Dampers (SFDs) are employed in high-speed Turbomachinery, particularly aircraft jet engines, to provide external damping. Despite numerous successful applications, it is widely acknowledged that the theoretical ...

  20. Numerical Simulation of Flow Field Inside a Squeeze Film Damper and the Study of the Effect of Cavitation on the Pressure Distribution

    E-Print Network [OSTI]

    Khandare, Milind Nandkumar

    2012-02-14T23:59:59.000Z

    of SFDs can be expensive and time consuming. The current work simulates the flow field inside the dynamically deforming annular gap of a SFD using the commercial computational fluid dynamics (CFD) code Fluent and compares the results to the experimental...

  1. New process to avoid emissions: Constant pressure in coke ovens

    SciTech Connect (OSTI)

    Giertz, J.; Huhn, F. [DMT-Gesellschaft fuer Forschung und Pruefung mbH, Essen (Germany). Inst. for Cokemaking and Fuel Technology; Hofherr, K. [Thyssen Stahl AG, Duisburg (Germany)

    1995-12-01T23:59:59.000Z

    A chamber pressure regulation (PROven), especially effective in regard to emission control problems of coke ovens is introduced for the first time. Because of the partial vacuum in the collecting main system, it is possible to keep the oven`s raw gas pressure constant on a low level over the full coking time. The individual pressure control for each chamber is assured directly as a function of the oven pressure by an immersion system controlling the flow resistance of the collecting main valve. The latter is a fixed-position design (system name ``FixCup``). By doing away with the interdependence of collecting main pressure and chamber pressure, a parameter seen as a coking constant could not be made variable. This opens a new way to reduce coke oven emissions and simultaneously to prevent the ovens from damage caused by air ingress into the oven.

  2. Pressurizer tank upper support

    DOE Patents [OSTI]

    Baker, Tod H. (O'Hara Township, Allegheny County, PA); Ott, Howard L. (Kiski Township, Armstrong County, PA)

    1994-01-01T23:59:59.000Z

    A pressurizer tank in a pressurized water nuclear reactor is mounted between structural walls of the reactor on a substructure of the reactor, the tank extending upwardly from the substructure. For bearing lateral loads such as seismic shocks, a girder substantially encircles the pressurizer tank at a space above the substructure and is coupled to the structural walls via opposed sway struts. Each sway strut is attached at one end to the girder and at an opposite end to one of the structural walls, and the sway struts are oriented substantially horizontally in pairs aligned substantially along tangents to the wall of the circular tank. Preferably, eight sway struts attach to the girder at 90.degree. intervals. A compartment encloses the pressurizer tank and forms the structural wall. The sway struts attach to corners of the compartment for maximum stiffness and load bearing capacity. A valve support frame carrying the relief/discharge piping and valves of an automatic depressurization arrangement is fixed to the girder, whereby lateral loads on the relief/discharge piping are coupled directly to the compartment rather than through any portion of the pressurizer tank. Thermal insulation for the valve support frame prevents thermal loading of the piping and valves. The girder is shimmed to define a gap for reducing thermal transfer, and the girder is free to move vertically relative to the compartment walls, for accommodating dimensional variation of the pressurizer tank with changes in temperature and pressure.

  3. Pressurizer tank upper support

    DOE Patents [OSTI]

    Baker, T.H.; Ott, H.L.

    1994-01-11T23:59:59.000Z

    A pressurizer tank in a pressurized water nuclear reactor is mounted between structural walls of the reactor on a substructure of the reactor, the tank extending upwardly from the substructure. For bearing lateral loads such as seismic shocks, a girder substantially encircles the pressurizer tank at a space above the substructure and is coupled to the structural walls via opposed sway struts. Each sway strut is attached at one end to the girder and at an opposite end to one of the structural walls, and the sway struts are oriented substantially horizontally in pairs aligned substantially along tangents to the wall of the circular tank. Preferably, eight sway struts attach to the girder at 90[degree] intervals. A compartment encloses the pressurizer tank and forms the structural wall. The sway struts attach to corners of the compartment for maximum stiffness and load bearing capacity. A valve support frame carrying the relief/discharge piping and valves of an automatic depressurization arrangement is fixed to the girder, whereby lateral loads on the relief/discharge piping are coupled directly to the compartment rather than through any portion of the pressurizer tank. Thermal insulation for the valve support frame prevents thermal loading of the piping and valves. The girder is shimmed to define a gap for reducing thermal transfer, and the girder is free to move vertically relative to the compartment walls, for accommodating dimensional variation of the pressurizer tank with changes in temperature and pressure. 10 figures.

  4. Nouvelles problematiques posees par le cyclage thermo-mecanique en cavites salines

    E-Print Network [OSTI]

    Pellizzaro, Cyrille; Brouard, Benot; Karimi-Jafari, Mehdi

    2013-01-01T23:59:59.000Z

    Storage of natural gas in salt caverns had been developed mainly for seasonal storage, resulting in a small number of yearly pressure cycles and moderate gas-production rates. The needs of energy traders are changing towards more aggressive operational modes. The "high-frequency cycling" operation of salt caverns raises questions concerning the effects of frequently repeated and intense mechanical and thermal loading. These questions concern the constitutive creep laws for salt, laboratory test procedures, criteria to be used at the design stage to provide operability, and the long-term integrity of the underground salt caverns.

  5. Ashtekar's variables without spin

    E-Print Network [OSTI]

    Thomas Schucker

    2009-06-26T23:59:59.000Z

    Ashtekar's variables are shown to arise naturally from a 3+1 split of general relativity in the Einstein-Cartan formulation. Thereby spinors are exorcised.

  6. Capacitance pressure sensor

    DOE Patents [OSTI]

    Eaton, William P. (Tijeras, NM); Staple, Bevan D. (Albuquerque, NM); Smith, James H. (Albuquerque, NM)

    2000-01-01T23:59:59.000Z

    A microelectromechanical (MEM) capacitance pressure sensor integrated with electronic circuitry on a common substrate and a method for forming such a device are disclosed. The MEM capacitance pressure sensor includes a capacitance pressure sensor formed at least partially in a cavity etched below the surface of a silicon substrate and adjacent circuitry (CMOS, BiCMOS, or bipolar circuitry) formed on the substrate. By forming the capacitance pressure sensor in the cavity, the substrate can be planarized (e.g. by chemical-mechanical polishing) so that a standard set of integrated circuit processing steps can be used to form the electronic circuitry (e.g. using an aluminum or aluminum-alloy interconnect metallization).

  7. High pressure counterflow CHF.

    E-Print Network [OSTI]

    Walkush, Joseph Patrick

    1975-01-01T23:59:59.000Z

    This is a report of the experimental results of a program in countercurrent flow critical heat flux. These experiments were performed with Freon 113 at 200 psia in order to model a high pressure water system. An internally ...

  8. Pressure suppression containment system

    DOE Patents [OSTI]

    Gluntz, D.M.; Townsend, H.E.

    1994-03-15T23:59:59.000Z

    A pressure suppression containment system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The wetwell pool includes a plenum for receiving the non-condensable gas carried with steam from the drywell following a loss-of-coolant-accident (LOCA). The wetwell plenum is vented to a plenum above the GDCS pool following the LOCA for suppressing pressure rise within the containment vessel. A method of operation includes channeling steam released into the drywell following the LOCA into the wetwell pool for cooling along with the non-condensable gas carried therewith. The GDCS pool is then drained by gravity, and the wetwell plenum is vented into the GDCS plenum for channeling the non-condensable gas thereto. 6 figures.

  9. Oxygen partial pressure sensor

    DOE Patents [OSTI]

    Dees, D.W.

    1994-09-06T23:59:59.000Z

    A method for detecting oxygen partial pressure and an oxygen partial pressure sensor are provided. The method for measuring oxygen partial pressure includes contacting oxygen to a solid oxide electrolyte and measuring the subsequent change in electrical conductivity of the solid oxide electrolyte. A solid oxide electrolyte is utilized that contacts both a porous electrode and a nonporous electrode. The electrical conductivity of the solid oxide electrolyte is affected when oxygen from an exhaust stream permeates through the porous electrode to establish an equilibrium of oxygen anions in the electrolyte, thereby displacing electrons throughout the electrolyte to form an electron gradient. By adapting the two electrodes to sense a voltage potential between them, the change in electrolyte conductivity due to oxygen presence can be measured. 1 fig.

  10. Pressure suppression containment system

    DOE Patents [OSTI]

    Gluntz, Douglas M. (San Jose, CA); Townsend, Harold E. (San Jose, CA)

    1994-03-15T23:59:59.000Z

    A pressure suppression containment system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The wetwell pool includes a plenum for receiving the non-condensable gas carried with steam from the drywell following a loss-of coolant-accident (LOCA). The wetwell plenum is vented to a plenum above the GDCS pool following the LOCA for suppressing pressure rise within the containment vessel. A method of operation includes channeling steam released into the drywell following the LOCA into the wetwell pool for cooling along with the non-condensable gas carried therewith. The GDCS pool is then drained by gravity, and the wetwell plenum is vented into the GDCS plenum for channeling the non-condensable gas thereto.

  11. Plating under reduced pressure

    SciTech Connect (OSTI)

    Dini, J.W.; Beat, T.G.; Cowden, W.C. (Lawrence Livermore National Lab., CA (United States)); Ryan, L.E.; Hewitt, W.B. (TRW, Inc., Redondo Beach, CA (United States))

    1992-06-01T23:59:59.000Z

    Plating under reduced pressure was evaluated for both electroless nickel and electrodeposited copper systems. The objective was to reduce pitting of these coatings thereby further enhancing their usage for diamond turning applications. Cursory experiments with electroless nickel showed reduced porosity when deposition was done at around 500 torr. Detailed experiments with electrodeposited copper at around 100 torr provided similar results. Scanning tunneling microscopy was effectively used to show the improvement in the copper deposits plated under reduced pressure. Benefits included reduced surface roughness and finer and denser grain structure.

  12. Understanding Biomass Feedstock Variability

    SciTech Connect (OSTI)

    Kevin L. Kenney; William A. Smith; Garold L. Gresham; Tyler L. Westover

    2013-01-01T23:59:59.000Z

    If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that due to inherent species variabilities, production conditions, and differing harvest, collection, and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture, and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

  13. Understanding Biomass Feedstock Variability

    SciTech Connect (OSTI)

    Kevin L. Kenney; Garold L. Gresham; William A. Smith; Tyler L. Westover

    2013-01-01T23:59:59.000Z

    If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per-ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that, due to inherent species variabilities, production conditions and differing harvest, collection and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

  14. Saltstone Osmotic Pressure

    SciTech Connect (OSTI)

    Nichols, Ralph L.; Dixon, Kenneth L.

    2013-09-23T23:59:59.000Z

    Recent research into the moisture retention properties of saltstone suggest that osmotic pressure may play a potentially significant role in contaminant transport (Dixon et al., 2009 and Dixon, 2011). The Savannah River Remediation Closure and Disposal Assessments Group requested the Savannah River National Laboratory (SRNL) to conduct a literature search on osmotic potential as it relates to contaminant transport and to develop a conceptual model of saltstone that incorporates osmotic potential. This report presents the findings of the literature review and presents a conceptual model for saltstone that incorporates osmotic potential. The task was requested through Task Technical Request HLW-SSF-TTR-2013-0004. Simulated saltstone typically has very low permeability (Dixon et al. 2008) and pore water that contains a large concentration of dissolved salts (Flach and Smith 2013). Pore water in simulated saltstone has a high salt concentration relative to pore water in concrete and groundwater. This contrast in salt concentration can generate high osmotic pressures if simulated saltstone has the properties of a semipermeable membrane. Estimates of osmotic pressure using results from the analysis of pore water collected from simulated saltstone show that an osmotic pressure up to 2790 psig could be generated within the saltstone. Most semi-permeable materials are non-ideal and have an osmotic efficiency <1 and as a result actual osmotic pressures are less than theoretical pressures. Observations from laboratory tests of simulated saltstone indicate that it may exhibit the behavior of a semi-permeable membrane. After several weeks of back pressure saturation in a flexible wall permeameter (FWP) the membrane containing a simulated saltstone sample appeared to have bubbles underneath it. Upon removal from the FWP the specimen was examined and it was determined that the bubbles were due to liquid that had accumulated between the membrane and the sample. One possible explanation for the accumulation of solution between the membrane and sample is the development of osmotic pressure within the sample. Osmotic pressure will affect fluid flow and contaminant transport and may result in the changes to the internal structure of the semi-permeable material. B?nard et al. 2008 reported swelling of wet cured Portland cement mortars containing salts of NaNO{sub 3}, KNO{sub 3}, Na{sub 3}PO{sub 4}x12H {sub 2}O, and K{sub 3}PO{sub 4} when exposed to a dilute solution. Typically hydraulic head is considered the only driving force for groundwater in groundwater models. If a low permeability material containing a concentrated salt solution is present in the hydrogeologic sequence large osmotic pressures may develop and lead to misinterpretation of groundwater flow and solute transport. The osmotic pressure in the semi-permeable material can significantly impact groundwater flow in the vicinity of the semi-permeable material. One possible outcome is that groundwater will flow into the semi-permeable material resulting in hydrologic containment within the membrane. Additionally, hyperfiltration can occur within semi-permeable materials when water moves through a membrane into the more concentrated solution and dissolved constituents are retained in the lower concentration solution. Groundwater flow and transport equations that incorporate chemical gradients (osmosis) have been developed. These equations are referred to as coupled flow equations. Currently groundwater modeling to assess the performance of saltstone waste forms is conducted using the PORFLOW groundwater flow and transport model. PORFLOW does not include coupled flow from chemico-osmotic gradients and therefore numerical simulation of the effect of coupled flow on contaminant transport in and around saltstone cannot be assessed. Most natural semi-permeable membranes are non-ideal membranes and do not restrict all movement of solutes and as a result theoretical osmotic potential is not realized. Osmotic efficiency is a parameter in the coupled flow equation that accounts for the

  15. Reactor pressure vessel nozzle

    DOE Patents [OSTI]

    Challberg, R.C.; Upton, H.A.

    1994-10-04T23:59:59.000Z

    A nozzle for joining a pool of water to a nuclear reactor pressure vessel includes a tubular body having a proximal end joinable to the pressure vessel and a distal end joinable in flow communication with the pool. The body includes a flow passage therethrough having in serial flow communication a first port at the distal end, a throat spaced axially from the first port, a conical channel extending axially from the throat, and a second port at the proximal end which is joinable in flow communication with the pressure vessel. The inner diameter of the flow passage decreases from the first port to the throat and then increases along the conical channel to the second port. In this way, the conical channel acts as a diverging channel or diffuser in the forward flow direction from the first port to the second port for recovering pressure due to the flow restriction provided by the throat. In the backflow direction from the second port to the first port, the conical channel is a converging channel and with the abrupt increase in flow area from the throat to the first port collectively increase resistance to flow therethrough. 2 figs.

  16. Electro-hydraulic control system for a dual-pass continuously variable transmission

    SciTech Connect (OSTI)

    Algrain, M.C.; Anderson, S.R.; Smirl, R.L.

    1991-07-16T23:59:59.000Z

    This patent describes a control system for controlling the hydraulic pressure in a dual-pass continuously variable transmission system having a plurality of drive paths from a power input to a power output, and a continuously variable component including first and second variable pulleys disposed respectively on first and second intermediate shafts, the transmission system having first and second clutches engagable to effect transition from a first drive path in which the first variable pulley is the driver pulley to a second drive path in which the second variable pulley is the driver pulley, the transmission system being releasable to effect a transition from the second drive path to the first drive path. It comprises means to provide a primary hydraulic pressure to each of the first and second variable pulleys; means for providing a secondary hydraulic pressure to each of the first and second variable pulleys; means for electrically regulating the primary and secondary pressures responsive to engine conditions; and means for directing the primary and secondary hydraulic pressures to the first and second variable pulleys in response to change of drive path.

  17. Development of models for series and parallel fan variable air volume terminal units

    E-Print Network [OSTI]

    Furr, James C., Jr

    2007-09-17T23:59:59.000Z

    Empirical models of airflow output and power consumption were developed for series and parallel fan powered variable air volume terminal units at typical design pressure conditions. A testing procedure and experimental setup were developed to test...

  18. Deconvolution of variable rate reservoir performance data using B-splines

    E-Print Network [OSTI]

    Ilk, Dilhan

    2007-04-25T23:59:59.000Z

    of permanent downhole gauges and large-scale processing/analysis of production data. Under these circumstances, our objective is to create a robust and practical tool which can tolerate reasonable variability and relatively large errors in rate and pressure...

  19. Variable Speed Drive (VSD) Applications in Dual-Duct Constant Volume Systems

    E-Print Network [OSTI]

    Joo, I.; Liu, M.; Conger, K.; Wang, G.

    2002-01-01T23:59:59.000Z

    Models have been developed for static pressure and potential supply fan energy savings by using variable speed drive (VSD) in dual-duct constant volume systems. Experiments have been performed using a full size dual-duct constant volume system...

  20. Cavitation on a modern ship propeller.This photograph was taken by Mark Duttweiler (PhD '01) in Caltech's Mechanical Engineering, Low Turbulence Water Tunnel. The flow is from right to left. Enter the second issue of ENGenious.

    E-Print Network [OSTI]

    Haile, Sossina M.

    Cavitation on a modern ship propeller.This photograph was taken by Mark Duttweiler (PhD '01 educations. The profile of alumnus Allen Puckett (PhD '49) starts a new feature we will be continuing in each, on behalf of the Division, Gordon Moore (PhD '54) and his wife, Betty, for their truly extraordinary

  1. A flexible pressure monitoring system for pressure ulcer prevention

    E-Print Network [OSTI]

    Yip, Marcus

    Pressure ulcers are painful sores that arise from prolonged exposure to high pressure points, which restricts blood flow and leads to tissue necrosis. This is a common occurrence among patients with impaired mobility, ...

  2. Pressure suppression system

    DOE Patents [OSTI]

    Gluntz, D.M.

    1994-10-04T23:59:59.000Z

    A pressure suppression system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and an enclosed gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The GDCS pool includes a plenum for receiving through an inlet the non-condensable gas carried with steam from the drywell following a loss-of-coolant accident (LOCA). A condenser is disposed in the GDCS plenum for condensing the steam channeled therein and to trap the non-condensable gas therein. A method of operation includes draining the GDCS pool following the LOCA and channeling steam released into the drywell following the LOCA into the GDCS plenum for cooling along with the non-condensable gas carried therewith for trapping the gas therein. 3 figs.

  3. Continuous pressure letdown system

    DOE Patents [OSTI]

    Sprouse, Kenneth M.; Matthews, David R.; Langowski, Terry

    2010-06-08T23:59:59.000Z

    A continuous pressure letdown system connected to a hopper decreases a pressure of a 2-phase (gas and solid) dusty gas stream flowing through the system. The system includes a discharge line for receiving the dusty gas from the hopper, a valve, a cascade nozzle assembly positioned downstream of the discharge line, a purge ring, an inert gas supply connected to the purge ring, an inert gas throttle, and a filter. The valve connects the hopper to the discharge line and controls introduction of the dusty gas stream into the discharge line. The purge ring is connected between the discharge line and the cascade nozzle assembly. The inert gas throttle controls a flow rate of an inert gas into the cascade nozzle assembly. The filter is connected downstream of the cascade nozzle assembly.

  4. High pressure furnace

    DOE Patents [OSTI]

    Morris, D.E.

    1993-09-14T23:59:59.000Z

    A high temperature high pressure furnace has a hybrid partially externally heated construction. A metallic vessel fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum)). The disclosed alloy is fabricated into 11/4 or 2 inch, 32 mm or 50 mm bar stock and has a length of about 22 inches, 56 cm. This bar stock has an aperture formed therein to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the vessel is provided with a small blind aperture into which a thermocouple can be inserted. The closed end of the vessel is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior. 19 figures.

  5. High pressure oxygen furnace

    DOE Patents [OSTI]

    Morris, Donald E. (Kensington, CA)

    1992-01-01T23:59:59.000Z

    A high temperature high pressure oxygen furnace having a hybrid partially externally heated construction is disclosed. A metallic bar fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 inch bar stock and has a length of about 17 inches. This bar stock is gun drilled for over 16 inches of its length with 0.400 inch aperture to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the bar is provided with a small support aperture into which both a support and a thermocouple can be inserted. The closed end of the gun drilled bar is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior.

  6. High pressure oxygen furnace

    DOE Patents [OSTI]

    Morris, D.E.

    1992-07-14T23:59:59.000Z

    A high temperature high pressure oxygen furnace having a hybrid partially externally heated construction is disclosed. A metallic bar fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized, the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 inch bar stock and has a length of about 17 inches. This bar stock is gun drilled for over 16 inches of its length with 0.400 inch aperture to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the bar is provided with a small support aperture into which both a support and a thermocouple can be inserted. The closed end of the gun drilled bar is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior. 5 figs.

  7. Pressure suppression system

    DOE Patents [OSTI]

    Gluntz, Douglas M. (San Jose, CA)

    1994-01-01T23:59:59.000Z

    A pressure suppression system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and an enclosed gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The GDCS pool includes a plenum for receiving through an inlet the non-condensable gas carried with steam from the drywell following a loss-of-coolant accident (LOCA). A condenser is disposed in the GDCS plenum for condensing the steam channeled therein and to trap the non-condensable gas therein. A method of operation includes draining the GDCS pool following the LOCA and channeling steam released into the drywell following the LOCA into the GDCS plenum for cooling along with the non-condensable gas carried therewith for trapping the gas therein.

  8. High pressure furnace

    DOE Patents [OSTI]

    Morris, Donald E. (Kensington, CA)

    1993-01-01T23:59:59.000Z

    A high temperature high pressure furnace has a hybrid partially externally heated construction. A metallic vessel fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 or 2 inch, 32 mm or 50 mm bar stock and has a length of about 22 inches, 56 cm. This bar stock has an aperture formed therein to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the vessel is provided with a small blind aperture into which a thermocouple can be inserted. The closed end of the vessel is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior.

  9. High pressure storage vessel

    DOE Patents [OSTI]

    Liu, Qiang

    2013-08-27T23:59:59.000Z

    Disclosed herein is a composite pressure vessel with a liner having a polar boss and a blind boss a shell is formed around the liner via one or more filament wrappings continuously disposed around at least a substantial portion of the liner assembly combined the liner and filament wrapping have a support profile. To reduce susceptible to rupture a locally disposed filament fiber is added.

  10. Economics of Steam Pressure Reduction

    E-Print Network [OSTI]

    Sylva, D. M.

    Economics of Steam Pressure Reduction is a technical paper that addresses the operating and economic advantages associated with the program to lower the steam operating pressure. Evaluation of a testing program will be discussed. The paper...

  11. Variable nonlinear resistances

    E-Print Network [OSTI]

    Howard, James Edgar

    1955-01-01T23:59:59.000Z

    VARIETAL". NONLINEAR RESIS'IANCES A Thes1s JA'. 4ES EDGAR HOWARD as to style and content by Head Department January 1955 LIBRARY A 4 IS COLLEGE PF TEXAS VARIABLE NONLINEAR RESISTANCES A Thesis By JAMES EDGAR HOWARD Submitted...

  12. Nitrogen at very high pressure

    SciTech Connect (OSTI)

    Nellis, W.J.

    1987-07-01T23:59:59.000Z

    High-pressure results for nitrogen are reviewed and discussed in terms of phenomena that occur at extreme conditions.

  13. Pressure Data Within BOP- ODS

    Broader source: Energy.gov [DOE]

    This file describes the components within the BOP and the pressure readings taken during diagnostic operations on May 25.

  14. Pressure Data Within BOP- XLS

    Broader source: Energy.gov [DOE]

    This file describes the components within the BOP and the pressure readings taken during diagnostic operations on May 25.

  15. Blood Pressure Medicine: Special Instructions

    E-Print Network [OSTI]

    Bandettini, Peter A.

    Blood Pressure Medicine: Special Instructions: U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health National Heart, Lung, and Blood Institute What is my blood pressure reading in numbers? What is my goal blood pressure? Is there a healthy eating plan that I should follow to help

  16. Envera Variable Compression Ratio Engine

    SciTech Connect (OSTI)

    Charles Mendler

    2011-03-15T23:59:59.000Z

    Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy has already demonstrated a degree of success, downsizing and fuel economy gains are currently limited. With new variable compression ratio technology however, the degree of engine downsizing and fuel economy improvement can be greatly increased. A small variable compression ratio (VCR) engine has the potential to return significantly higher vehicle fuel economy while also providing high power. Affordability and potential for near term commercialization are key attributes of the Envera VCR engine. VCR Technology To meet torque and power requirements, a smaller engine needs to do more work per stroke. This is typically accomplished by boosting the incoming charge with either a turbo or supercharger so that more energy is present in the cylinder per stroke to do the work. With current production engines the degree of engine boosting (which correlates to downsizing) is limited by detonation (combustion knock) at high boost levels. Additionally, the turbo or supercharger needs to be responsive and efficient while providing the needed boost. VCR technology eliminates the limitation of engine knock at high load levels by reducing compression ratio to {approx}9:1 (or whatever level is appropriate) when high boost pressures are needed. By reducing the compression ratio during high load demand periods there is increased volume in the cylinder at top dead center (TDC) which allows more charge (or energy) to be present in the cylinder without increasing the peak pressure. Cylinder pressure is thus kept below the level at which the engine would begin to knock. When loads on the engine are low the compression ratio can be raised (to as much as 18:1) providing high engine efficiency. It is important to recognize that for a well designed VCR engine cylinder pressure does not need to be higher than found in current production turbocharged engines. As such, there is no need for a stronger crankcase, bearings and other load bearing parts within the VCR engine. The Envera VCR mechanism uses an eccentric carrier approach to adjust engine compression ratio. The crankshaft main bearings are mounted in this eccentric carrier or 'crankshaft cradle' and pivoting the eccentric carrier 30 degrees adjusts compression ratio from 9:1 to 18:1. The eccentric carrier is made up of a casting that provides rigid support for the main bearings, and removable upper bearing caps. Oil feed to the main bearings transits through the bearing cap fastener sockets. The eccentric carrier design was chosen for its low cost and rigid support of the main bearings. A control shaft and connecting links are used to pivot the eccentric carrier. The control shaft mechanism features compression ratio lock-up at minimum and maximum compression ratio settings. The control shaft method of pivoting the eccentric carrier was selected due to its lock-up capability. The control shaft can be rotated by a hydraulic actuator or an electric motor. The engine shown in Figures 3 and 4 has a hydraulic actuator that was developed under the current program. In-line 4-cylinder engines are significantly less expensive than V engines because an entire cylinder head can be eliminated. The cost savings from eliminating cylinders and an entire cylinder head will notably offset the added cost of the VCR and supercharging. Replacing V6 and V8 engines with in-line VCR 4-cylinder engines will provide high fuel economy at low cost. Numerous enabling technologies exist which have the potential to increase engine efficiency. The greatest efficiency gains are realized when the right combination of advanced and new technologies are packaged together to provide the greatest gains at the least cost. Aggressive engine downsiz

  17. Submitted to Journal of Physical Oceanography Sea Surface Temperature Variability Along the Path of the Antarctic

    E-Print Network [OSTI]

    Czaja, Arnaud

    level pressure and air-sea heat fluxes. It is found that a significant fraction of SST variability) and remote forcing by ENSO. The physical mechanisms rely on the interplay between atmospheric variability the South Pa- cific, inducing surface heat fluxes (Fs) and Ekman heat advection (Fek) anomalies. A simple

  18. High-pressure neutron diffraction

    SciTech Connect (OSTI)

    Xu, Hongwu [Los Alamos National Laboratory

    2011-01-10T23:59:59.000Z

    This lecture will cover progress and prospect of applications of high-pressure neutron diffraction techniques to Earth and materials sciences. I will first introduce general high-pressure research topics and available in-situ high-pressure techniques. Then I'll talk about high-pressure neutron diffraction techniques using two types of pressure cells: fluid-driven and anvil-type cells. Lastly, I will give several case studies using these techniques, particularly, those on hydrogen-bearing materials and magnetic transitions.

  19. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, P.M.; Reger, R.J.

    1996-02-20T23:59:59.000Z

    A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

  20. Variable Crop Share Leases.

    E-Print Network [OSTI]

    Sartin, Marvin; Sammons, Ray

    1980-01-01T23:59:59.000Z

    )OC lAL45.7 173 1. 1224 Texas Agricultural Extension Service The Texas A&M University System Daniel C. Pfannstiel,Director colleg e Station, Texas / f , ' '~ :';,; ,,: ''': ~ " k , -~. _Variable _Crop Share _Leases ... Marvin... Sartin and Ray Sammons* Renting or leasing farmland is part of many modern farming operations and increases average farm size in U. S. agriculture. Economies of size are vitally import ant to farm operations as they strive to cope with the continuous...

  1. Variable Frequency Pump Drives

    E-Print Network [OSTI]

    Karassik, I. J.; Petraccaro, L. L.; McGuire, J. T.

    . In a conventional pump and driver arrangement (for example, a centrifugal pump coupled to an AC induction motor'with no speed control provision), the motor runs at. a constant speed, which is determined by the incoming line frequency, and the pump... when it is needed. LONG RANGE DESIGN TRENDS The growing use of variable-frequency electric motor drives will permit the integration of 60 and 50 cycle pump lines. One important concern for future improvements is the growing possibility...

  2. Theoretical collapse pressures for two pressurized torispherical heads

    SciTech Connect (OSTI)

    Kalnins, A.; Updike, D.P. [Lehigh Univ., Bethlehem, PA (United States); Rana, M.D. [Praxair, Inc., Tonawanda, NY (United States). Research and Development Dept.

    1995-12-01T23:59:59.000Z

    In order to determine the pressures at which real torispherical heads fail upon a single application of pressure, two heads were pressurized in recent Praxair tests, and displacements and strains were recorded at various locations. In this paper, theoretical results for the two test heads are presented in the form of curves of pressure versus crown deflections, using the available geometry and material parameters. From these curves, limit and collapse pressures are calculated, using procedures permitted by the ASME B and PV Code Section 8/Div.2. These pressures are shown to vary widely, depending on the method and model used to calculate them. The effect of no stress relief on the behavior of the Praxair test heads is also evaluated and found to be of no significance for neither the objectives of the tests nor the objectives of this paper. The results of this paper are submitted as an enhancement to the experimental results recorded during the Praxair tests.

  3. Cradle and pressure grippers

    DOE Patents [OSTI]

    Muniak, John E. (New York, NY)

    2001-01-01T23:59:59.000Z

    A gripper that is designed to incorporate the functions of gripping, supporting and pressure tongs into one device. The gripper has two opposing finger sections with interlocking fingers that incline and taper to form a wedge. The interlocking fingers are vertically off-set so that the opposing finger sections may close together allowing the inclined, tapered tips of the fingers to extend beyond the plane defined by the opposing finger section's engagement surface. The range of motion defined by the interlocking relationship of the finger sections allows the gripper to grab, lift and support objects of varying size and shape. The gripper has one stationary and one moveable finger section. Power is provided to the moveable finger section by an actuating device enabling the gripper to close around an object to be lifted. A lifting bail is attached to the gripper and is supported by a crane that provides vertical lift.

  4. Steam Oxidation at High Pressure

    SciTech Connect (OSTI)

    Holcomb, Gordon R. [NETL; Carney, Casey [URS

    2013-07-19T23:59:59.000Z

    A first high pressure test was completed: 293 hr at 267 bar and 670{degrees}C; A parallel 1 bar test was done for comparison; Mass gains were higher for all alloys at 267 bar than at 1 bar; Longer term exposures, over a range of temperatures and pressures, are planned to provide information as to the commercial implications of pressure effects; The planned tests are at a higher combination of temperatures and pressures than in the existing literature. A comparison was made with longer-term literature data: The short term exposures are largely consistent with the longer-term corrosion literature; Ferritic steels--no consistent pressure effect; Austenitic steels--fine grain alloys less able to maintain protective chromia scale as pressure increases; Ni-base alloys--more mass gains above 105 bar than below. Not based on many data points.

  5. Cosmological perturbations of a perfect fluid and noncommutative variables

    SciTech Connect (OSTI)

    De Felice, Antonio; Gerard, Jean-Marc; Suyama, Teruaki [Centre for Particle Physics and Phenomenology (CP3), Universite catholique de Louvain, Chemin du Cyclotron 2, B-1348 Louvain-la-Neuve (Belgium)

    2010-03-15T23:59:59.000Z

    We describe the linear cosmological perturbations of a perfect fluid at the level of an action, providing thus an alternative to the standard approach based only on the equations of motion. This action is suited not only to perfect fluids with a barotropic equation of state, but also to those for which the pressure depends on two thermodynamical variables. By quantizing the system we find that (1) some perturbation fields exhibit a noncommutativity quite analogous to the one observed for a charged particle moving in a strong magnetic field, (2) local curvature and pressure perturbations cannot be measured simultaneously, (3) ghosts appear if the null energy condition is violated.

  6. Energy Systems High Pressure Test Laboratory (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-10-01T23:59:59.000Z

    This fact sheet describes the purpose, lab specifications, applications scenarios, and information on how to partner with NREL's Energy Systems High Pressure Test Laboratory at the Energy Systems Integration Facility. The purpose of the Energy Systems High Pressure Test Laboratory at NREL's Energy Systems Integration Facility (ESIF) is to provide space where high pressure hydrogen components can be safely tested. High pressure hydrogen storage is an integral part of energy storage technology for use in fuel cell and in other distributed energy scenarios designed to effectively utilize the variability inherent with renewable energy sources. The high pressure storage laboratory is co-located with energy storage activities such as ultra-capacitors, super conducting magnetic flywheel and mechanical energy storage systems laboratories for an integrated approach to system development and demonstration. Hazards associated with hydrogen storage at pressures up to 10,000 psi include oxygen displacement, combustion, explosion, and pressurization of room air due to fast release and physical hazards associated with burst failure modes. A critical understanding of component failure modes is essential in developing reliable, robust designs that will minimize failure risk beyond the end of service life. Development of test protocol for accelerated life testing to accurately scale to real world operating conditions is essential for developing regulations, codes and standards required for safe operation. NREL works closely with industry partners in providing support of advanced hydrogen technologies. Innovative approaches to product design will accelerate commercialization into new markets. NREL works with all phases of the product design life cycle from early prototype development to final certification testing. High pressure tests are performed on hydrogen components, primarily for the validation of developing new codes and standards for high pressure hydrogen applications. The following types of tests can be performed: Performance, Component and system level efficiency, Strength of materials and hydrogen compatibility, Safety demonstration, Model validation, and Life cycle reliability.

  7. High Pressure Hydrogen Materials Compatibility of Piezoelectric...

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

    Pressure Hydrogen Materials Compatibility of Piezoelectric Films. High Pressure Hydrogen Materials Compatibility of Piezoelectric Films. Abstract: Abstract: Hydrogen is being...

  8. To estimate vapor pressure easily

    SciTech Connect (OSTI)

    Yaws, C.L.; Yang, H.C. (Lamar Univ., Beaumont, TX (USA))

    1989-10-01T23:59:59.000Z

    Vapor pressures as functions of temperature for approximately 700 major organic chemical compounds are given. The tabulation also gives the temperature range for which the data are applicable. Minimum and maximum temperatures are denoted by TMIN and TMAX. The Antoine equation that correlates vapor pressure as a function of temperature is described. A representative comparison of calculated and actual data values for vapor pressure is shown for ethyl alcohol. The coefficient tabulation is based on both literature (experimental data) and estimated values.

  9. Pressure testing of torispherical heads

    SciTech Connect (OSTI)

    Rana, M.D. [Praxair, Inc., Tonawanda, NY (United States). Research and Development Dept.; Kalnins, A.; Updike, D.P. [Lehigh Univ., Bethlehem, PA (United States)

    1995-12-01T23:59:59.000Z

    Two vessels fabricated from SA516-70 steel with 6% knuckle radius torispherical heads were tested under internal pressure to failure. The D/t ratios of Vessel 1 and Vessel 2 were 238 and 185 respectively. The calculated maximum allowable working pressures of Vessel 1 and 2 heads using the ASME Section 8, Div. 1 rules and measured dimensions were 85 and 110 psi, respectively. Vessel 1 failed at a nozzle weld in the cylindrical shell at 700 psi pressure. Neither buckling nor any other objectionable deformation of the head was observed at a theoretical double-elastic-slope collapse pressure of 241 and a calculated buckling pressure of 270 psi. Buckles were observed developing slowly after 600 psi pressure, and a total of 22 buckles were observed after the test, having the maximum amplitude of 0.15 inch. Vessel 2 failed at the edge of the longitudinal weld of the cylindrical shell at 1,080 psi pressure. Neither buckling nor any other objectionable deformation of the head was observed up to the final pressure, which exceeded the theoretical double-elastic-slope collapse and calculated buckling pressures of 274 psi and 342 psi, respectively.

  10. Variable Valve Actuation

    SciTech Connect (OSTI)

    Jeffrey Gutterman; A. J. Lasley

    2008-08-31T23:59:59.000Z

    Many approaches exist to enable advanced mode, low temperature combustion systems for diesel engines - such as premixed charge compression ignition (PCCI), Homogeneous Charge Compression Ignition (HCCI) or other HCCI-like combustion modes. The fuel properties and the quantity, distribution and temperature profile of air, fuel and residual fraction in the cylinder can have a marked effect on the heat release rate and combustion phasing. Figure 1 shows that a systems approach is required for HCCI-like combustion. While the exact requirements remain unclear (and will vary depending on fuel, engine size and application), some form of substantially variable valve actuation is a likely element in such a system. Variable valve actuation, for both intake and exhaust valve events, is a potent tool for controlling the parameters that are critical to HCCI-like combustion and expanding its operational range. Additionally, VVA can be used to optimize the combustion process as well as exhaust temperatures and impact the after treatment system requirements and its associated cost. Delphi Corporation has major manufacturing and product development and applied R&D expertise in the valve train area. Historical R&D experience includes the development of fully variable electro-hydraulic valve train on research engines as well as several generations of mechanical VVA for gasoline systems. This experience has enabled us to evaluate various implementations and determine the strengths and weaknesses of each. While a fully variable electro-hydraulic valve train system might be the 'ideal' solution technically for maximum flexibility in the timing and control of the valve events, its complexity, associated costs, and high power consumption make its implementation on low cost high volume applications unlikely. Conversely, a simple mechanical system might be a low cost solution but not deliver the flexibility required for HCCI operation. After modeling more than 200 variations of the mechanism it was determined that the single cam design did not have enough flexibility to satisfy three critical OEM requirements simultaneously, (maximum valve lift variation, intake valve opening timing and valve closing duration), and a new approach would be necessary. After numerous internal design reviews including several with the OEM a dual cam design was developed that had the flexibility to meet all motion requirements. The second cam added complexity to the mechanism however the cost was offset by the deletion of the electric motor required in the previous design. New patent applications including detailed drawings and potential valve motion profiles were generated and alternate two cam designs were proposed and evaluated for function, cost, reliability and durability. Hardware was designed and built and testing of sample hardware was successfully completed on an engine test stand. The mechanism developed during the course of this investigation can be applied by Original Equipment Manufacturers, (OEM), to their advanced diesel engines with the ultimate goal of reducing emissions and improving fuel economy. The objectives are: (1) Develop an optimal, cost effective, variable valve actuation (VVA) system for advanced low temperature diesel combustion processes. (2) Design and model alternative mechanical approaches and down-select for optimum design. (3) Build and demonstrate a mechanism capable of application on running engines.

  11. Design of a variable-conductance vacuum insulation

    SciTech Connect (OSTI)

    Benson, D K; Potter, T F; Tracy, C E

    1994-01-01T23:59:59.000Z

    This paper describes one approach to the design of a variable-conductance vacuum insulation. In this design, the vacuum insulation consists of a permanently sealed, thin sheet steel, evacuated envelope of whatever geometry is required for the application. The steel envelope is supported internally against the atmospheric pressure loads by an array of discrete, low-conductance, ceramic supports, and radiative heat transfer is blocked by layers of thin metal radiation shields. Thermal conductance through this insulation is controlled electronically by changing the temperature of a small metal hydride connected to the vacuum envelope. The hydride reversibly absorbs/desorbs hydrogen to produce a hydrogen pressure typically within the range from less than 10{sup {minus}6} to as much as 1 torr. Design calculations are compared with results from laboratory tests of bench scale samples, and some possible automotive applications for this variable-conductance vacuum insulation are suggested.

  12. Electrokinetically pumped high pressure sprays

    DOE Patents [OSTI]

    Schoeniger, Joseph S. (Oakland, CA); Paul, Phillip H. (Livermore, CA); Schoeniger, Luke (Pittsford, NY)

    2002-01-01T23:59:59.000Z

    An electrokinetic pump capable of producing high pressure is combined with a nozzle having a submicron orifice to provide a high pressure spray device. Because of its small size, the device can be contained within medical devices such as an endoscope for delivering biological materials such as DNA, chemo therapeutic agents, or vaccines to tissues and cells.

  13. Possible Pressure Effect for Superconductors

    E-Print Network [OSTI]

    A. Kwang-Hua Chu

    2005-08-30T23:59:59.000Z

    We make an estimate of the possible range of $\\Delta T_c$ induced by high-pressure effects in post-metallic superconductors by using the theory of {\\it extended irreversible/reversible thermodynamics} and Pippard's length scale. The relationship between the increment of the superconducting temperature and the increase of the pressure is parabolic.

  14. Balanced pressure gerotor fuel pump

    DOE Patents [OSTI]

    Raney, Michael Raymond; Maier, Eugen

    2004-08-03T23:59:59.000Z

    A gerotor pump for pressurizing gasoline fuel is capable of developing pressures up to 2.0 MPa with good mechanical and volumetric efficiency and satisfying the durability requirements for an automotive fuel pump. The pump has been designed with optimized clearances and by including features that promote the formation of lubricating films of pressurized fuel. Features of the improved pump include the use of a shadow port in the side plate opposite the outlet port to promote balancing of high fuel pressures on the opposite sides of the rotors. Inner and outer rotors have predetermined side clearances with the clearances of the outer rotor being greater than those of the inner rotor in order to promote fuel pressure balance on the sides of the outer rotor. Support of the inner rotor and a drive shaft on a single bushing with bearing sleeves maintains concentricity. Additional features are disclosed.

  15. Status of R&D on Mitigating the Effects of Pressure Waves for the Spallation Neutron Source Mercury Target

    SciTech Connect (OSTI)

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

    2012-01-01T23:59:59.000Z

    The Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory has been conducting R&D on mitigating the effects of pressure waves in mercury spallation targets since 2001. More precisely, cavitation damage of the target vessel caused by the short beam pulse threatens to limit its lifetime more severely than radiation damage as well as limit its ultimate power capacity and hence its neutron intensity performance. The R&D program has moved from verification of the beam-induced damage phenomena to study of material and surface treatments for damage resistance to the current emphasis on gas injection techniques for damage mitigation. Two techniques are being worked on: injection of small dispersed gas bubbles that mitigate the pressure waves volumetrically; and protective gas walls that isolate the vessel from the damaging effects of collapsing cavitation bubbles. The latter has demonstrated good damage mitigation during in-beam testing with limited pulses, and adequate gas wall coverage at the beam entrance window has been demonstrated with the SNS mercury target flow configuration using a full scale mercury test loop. A question on the required area coverage remains which depends on results from SNS target post irradiation examination. The small gas bubble technique has been less effective during past in-beam tests but those results were with un-optimized and un-verified bubble populations. Another round of in-beam tests with small gas bubbles is planned for 2011. The first SNS target was removed from service in mid 2009 and samples were cut from two locations at the target s beam entrance window. Through-wall damage was observed at the innermost mercury vessel wall (not a containment wall). The damage pattern suggested correlation with the local mercury flow condition which is nearly stagnant at the peak damage location. Detailed post irradiation examination of the samples is under way that will assess the erosion and measure irradiation-induced changes in mechanical properties. Similar samples were cut from the second SNS target after it was removed from service in mid 2010. More extensive damage was observed on the target inner wall but damage to the containment wall was minimal.

  16. Pressure sensor for sealed containers

    DOE Patents [OSTI]

    Hodges, Franklin R. (Loudon, TN)

    2001-01-01T23:59:59.000Z

    A magnetic pressure sensor for sensing a pressure change inside a sealed container. The sensor includes a sealed deformable vessel having a first end attachable to an interior surface of the sealed container, and a second end. A magnet mounted to the vessel second end defining a distance away from the container surface provides an externally detectable magnetic field. A pressure change inside the sealed container causes deformation of the vessel changing the distance of the magnet away from the container surface, and thus the detectable intensity of the magnetic field.

  17. Electrokinetic high pressure hydraulic system

    DOE Patents [OSTI]

    Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA)

    2000-01-01T23:59:59.000Z

    A compact high pressure hydraulic pump having no moving mechanical parts for converting electric potential to hydraulic force. The electrokinetic pump, which can generate hydraulic pressures greater than 2500 psi, can be employed to compress a fluid, either liquid or gas, and manipulate fluid flow. The pump is particularly useful for capillary-base systems. By combining the electrokinetic pump with a housing having chambers separated by a flexible member, fluid flow, including high pressure fluids, is controlled by the application of an electric potential, that can vary with time.

  18. Evaluation of pressure sensing concepts: A technology assessment

    SciTech Connect (OSTI)

    Shepard, R.L.; Thacker, L.H.

    1993-09-01T23:59:59.000Z

    Advanced distributed control systems for electric power plants will require more accurate and reliable pressure gauges than those now installed. Future developments in power plant control systems are expected to use digital/optical networks rather than the analog/electric data transmission used in existing plants. Many pressure transmitters now installed use oil filling to separate process fluids from the gauge mechanism and are subject to insidious failures when the oil leaks. Testing and maintenance of pressure channels occupy a disproportionately large amount of effort to restore their accuracy and verify their operability. These and similar concerns have prompted an assessment of a broad spectrum of sensor technologies to aid in selecting the most likely candidates for adaptation to power plant applications. Ten representative conventional and thirty innovational pressure sensors are described and compared. Particular emphasis is focused on two categories: Silicon-integrated pressure sensors and fiber-optic sensors, and both of these categories are discussed in detail. Additional attractive concepts include variable reluctance gauges and resonant structure gauges that may not require oil buffering from the process fluid.

  19. OVERBURDEN PRESSURE AFFECTS FRACTURE APERTURE

    E-Print Network [OSTI]

    Schechter, David S.

    OVERBURDEN PRESSURE AFFECTS FRACTURE APERTURE AND FRACTURE PERMEABILITY IN A FRACTURED RESERVOIR are in integrated reservoir study, reservoir charac- terization, naturally fractured reservoirs, waterflooding in Hydraulically and Naturally Fractured Reservoirs." His research areas include experimental analysis

  20. Electrokinetic high pressure hydraulic system

    DOE Patents [OSTI]

    Paul, Phillip H.; Rakestraw, David J.; Arnold, Don W.; Hencken, Kenneth R.; Schoeniger, Joseph S.; Neyer, David W.

    2003-06-03T23:59:59.000Z

    An electrokinetic high pressure hydraulic pump for manipulating fluids in capillary-based system. The pump uses electro-osmotic flow to provide a high pressure hydraulic system, having no moving mechanical parts, for pumping and/or compressing fluids, for providing valve means and means for opening and closing valves, for controlling fluid flow rate, and manipulating fluid flow generally and in capillary-based systems (microsystems), in particular. The compact nature of the inventive high pressure hydraulic pump provides the ability to construct a micro-scale or capillary-based HPLC system that fulfills the desire for small sample quantity, low solvent consumption, improved efficiency, the ability to run samples in parallel, and field portability. Control of pressure and solvent flow rate is achieved by controlling the voltage applied to an electrokinetic pump.

  1. Electrokinetic high pressure hydraulic system

    DOE Patents [OSTI]

    Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA); Arnold, Don W. (Livermore, CA); Hencken, Kenneth R. (Pleasanton, CA); Schoeniger, Joseph S. (Oakland, CA); Neyer, David W. (Castro Valley, CA)

    2001-01-01T23:59:59.000Z

    An electrokinetic high pressure hydraulic pump for manipulating fluids in capillary-based systems. The pump uses electro-osmotic flow to provide a high pressure hydraulic system, having no moving mechanical parts, for pumping and/or compressing fluids, for providing valve means and means for opening and closing valves, for controlling fluid flow rate, and manipulating fluid flow generally and in capillary-based systems (Microsystems), in particular. The compact nature of the inventive high pressure hydraulic pump provides the ability to construct a micro-scale or capillary-based HPLC system that fulfills the desire for small sample quantity, low solvent consumption, improved efficiency, the ability to run samples in parallel, and field portability. Control of pressure and solvent flow rate is achieved by controlling the voltage applied to an electrokinetic pump.

  2. Increase Your Boiler Pressure to Decrease Your Electric Bill: The True Cost of CHP

    E-Print Network [OSTI]

    Downing, A.

    2011-01-01T23:59:59.000Z

    benefit of clean, low cost and reliable onsite power production. Introduction What if plant designers could create a payback on a replacement or new boiler? Operators still get the heat for the process, but now instead of a large capital investment... is not complicated and produces real savings. For our analysis, a company is examining the economic and operating variables inherit with replacing their current 65 psig low pressure boiler with a high pressure 400 psig boiler. They still only require 65 psig...

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

    SciTech Connect (OSTI)

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

    2013-07-01T23:59:59.000Z

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

  4. Buffering blood pressure fluctuations by respiratory sinus arrhythmia may in fact enhance them: a theoretical analysis

    E-Print Network [OSTI]

    Teodor Buchner; Jan ?ebrowski; Grzegorz Gielerak

    2010-07-13T23:59:59.000Z

    Using a three-compartment model of blood pressure dynamics, we analyze theoretically the short term cardiovascular variability: how the respiratory-related blood pressure fluctuations are buffered by appropriate heart rate changes: i.e. the respiratory sinus arrhythmia. The buffering is shown to be crucially dependent on the time delay between the stimulus (such as e.g. the inspiration onset) and the application of the control (the moment in time when the efferent response is delivered to the heart). This theoretical analysis shows that the buffering mechanism is effective only in the upright position of the body. It explains a paradoxical effect of enhancement of the blood pressure fluctuations by an ineffective control. Such a phenomenon was observed experimentally. Using the basis of the model, we discuss the blood pressure variability and heart rate variability under such clinical conditions as the states of expressed adrenergic drive and the tilt-test during the parasympathetic blockade or fixed rate atrial pacing. From the results of the variability analysis we draw a conclusion that the control of blood pressure in the HF band does not directly obtain the arterial baroreceptor input. We also discuss methodological issues of baroreflex sensitivity and sympathovagal balance assessment.

  5. Reaction rates from pressure-gauge measurements in reacting explosives

    SciTech Connect (OSTI)

    Ginsberg, M.J.; Anderson, A.B.; Wackerle, J.

    1981-01-01T23:59:59.000Z

    The proper hydrodynamic data and an equation of state are sufficient to describe quantitatively the reaction rates of explosives during the shock-to-detonation transition. Manganin pressure gauges embedded in the reacting explosive have provided these data for the explosives PETN, PBX 9404, TATB, and TNT. Once a pressure-field history has been assembled from individual pressure histories at different depths in the explosive, the conservation equations can be applied in a Lagrangian analysis of the data. The combination of a reactant-product equation of state with this analysis then allows the calculation of the extent of reaction and reaction rate. Successful correlation of the calculated reaction rate values with other thermodynamic variables, such as pressure or temperature, allows formulation of a rate law and the prediction of initiation behavior under circumstances quite different from the experiments that led to the rate law. The best dynamic piezoresistive pressure gauge for most applications would have a substantial output voltage and present negligible disturbance to the flow. In explosives, however, requirements for survival in the extreme temperature and pressure environment encountered by the gauge dictate compromise. Low electrical resistance (approx. 20 m..cap omega..) helps to minimize shunt conductivity failures, but this drastically reduces output and demands that much attention be given to reducingnoise. Although relatively thick insulation perturbs the flow to some extent, survivability requirements dictate its use. Pressure measurements in reactive flow can now be made routinely with gauges that successfully produce data leading to a description of the flow and a powerful predictive capability.

  6. Spray bottle apparatus with pressure multiplying pistons

    DOE Patents [OSTI]

    Moss, Owen R. (Kennewick, WA); Gordon, Norman R. (Kennewick, WA); DeFord, Henry S. (Kennewick, WA)

    1990-01-01T23:59:59.000Z

    The present invention comprises a spray bottle in which the pressure resulting from the gripping force applied by the user is amplified and this increased pressure used in generating a spray such as an aerosol or fluid stream. In its preferred embodiment, the invention includes a high pressure chamber and a corresponding piston which is operative for driving fluid out of this chamber at high pressure through a spray nozzle and a low pressure chamber and a corresponding piston which is acted upon the hydraulic pressure within the bottle resulting from the gripping force. The low pressure chamber and piston are of larger size than the high pressure chamber and piston. The pistons are rigidly connected so that the force created by the pressure acting on the piston in the low pressure chamber is transmitted to the piston in the high pressure chamber where it is applied over a more limited area thereby generating greater hydraulic pressure for use in forming the spray.

  7. The Chilled Water and Hot Water Building Differential Pressure Setpoint Calculation - Chilled Water and Hot Water Pump Speed Control

    E-Print Network [OSTI]

    Turner, W. D.; Bruner, H., Jr.; Claridge, D.; Liu, C.; Deng, S.

    2002-01-01T23:59:59.000Z

    A&M University College Station, TX ABSTRACT More and more variable frequency devices (VFD) are being installed on the chilled water and hot water pumps on the TAMU campus. Those pump speeds are varied to maintain chilled water... and the rest 46 buildings are located on the west campus. More and more variable frequency devices (VFD) are installed on chilled water and hot water pumps. The variable speed pump has reduced the over-pressuring of water systems and reduced pump...

  8. Flexible Pressure Sensors: Modeling and Experimental Characterization

    E-Print Network [OSTI]

    Viana, J.C.

    Flexible capacitive pressure sensors fabricated with nanocomposites were experimentally characterized and results compared with simulations from analytical modeling. Unlike traditional diaphragm silicon pressure sensors, ...

  9. Documentation Requirements for Pressurized Experiment Equipment

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

    Documentation Requirements for Pressurized Experiment Apparatus PSSC NOTE01 15-Jan-2013 When bringing a piece of apparatus to the APS for an experiment that will involve pressure,...

  10. High pressure neon arc lamp

    DOE Patents [OSTI]

    Sze, Robert C.; Bigio, Irving J.

    2003-07-15T23:59:59.000Z

    A high pressure neon arc lamp and method of using the same for photodynamic therapies is provided. The high pressure neon arc lamp includes a housing that encloses a quantity of neon gas pressurized to about 500 Torr to about 22,000 Torr. At each end of the housing the lamp is connected by electrodes and wires to a pulse generator. The pulse generator generates an initial pulse voltage to breakdown the impedance of the neon gas. Then the pulse generator delivers a current through the neon gas to create an electrical arc that emits light having wavelengths from about 620 nanometers to about 645 nanometers. A method for activating a photosensitizer is provided. Initially, a photosensitizer is administered to a patient and allowed time to be absorbed into target cells. Then the high pressure neon arc lamp is used to illuminate the target cells with red light having wavelengths from about 620 nanometers to about 645 nanometers. The red light activates the photosensitizers to start a chain reaction that may involve oxygen free radicals to destroy the target cells. In this manner, a high pressure neon arc lamp that is inexpensive and efficiently generates red light useful in photodynamic therapy is provided.

  11. Variable rate CELP speech coding using widely variable parameter updates

    E-Print Network [OSTI]

    Moodie, Myron L.

    1995-01-01T23:59:59.000Z

    bit rates for a given quality level. This work develops new techniques, referred to as widely variable CELP parameter updates, which dynamically adapt the transmit frequency of the CELP spectral parameters to the characteristics of the input speech...

  12. Quantum information with modular variables

    E-Print Network [OSTI]

    A. Ketterer; S. P. Walborn; A. Keller; T. Coudreau; P. Milman

    2014-06-24T23:59:59.000Z

    We introduce a novel strategy, based on the use of modular variables, to encode and deterministically process quantum information using states described by continuous variables. Our formalism leads to a general recipe to adapt existing quantum information protocols, originally formulated for finite dimensional quantum systems, to infinite dimensional systems described by continuous variables. This is achieved by using non unitary and non-gaussian operators, obtained from the superposition of gaussian gates, together with adaptative manipulations in qubit systems defined in infinite dimensional Hilbert spaces. We describe in details the realization of single and two qubit gates and briefly discuss their implementation in a quantum optical set-up.

  13. Local charge transport properties of hydrazine reduced monolayer graphene oxide sheets prepared under pressure condition

    SciTech Connect (OSTI)

    Ryuzaki, Sou, E-mail: ryuzaki.soh.341@m.kyushu-u.ac.jp; Meyer, Jakob A. S.; Petersen, Sren; Nrgaard, Kasper; Hassenkam, Tue; Laursen, Bo W. [Nano-Science Center and Department of Chemistry, University of Copenhagen, Universitetparken 5, 2100 Kbenhaven (Denmark)

    2014-09-01T23:59:59.000Z

    Charge transport properties of chemically reduced graphene oxide (RGO) sheets prepared by treatment with hydrazine were examined using conductive atomic force microscopy. The current-voltage (I-V) characteristics of monolayer RGO sheets prepared under atmospheric pressure followed an exponentially increase due to 2D variable-range hopping conduction through small graphene domains in an RGO sheet containing defect regions of residual sp{sup 3} carbon clusters bonded to oxygen groups, whereas RGO sheets prepared in a closed container under moderate pressure showed linear I-V characteristics with a conductivity of 267.2?537.5?S/m. It was found that the chemical reduction under pressure results in larger graphene domains (sp{sup 2} networks) in the RGO sheets when compared to that prepared under atmospheric pressure, indicating that the present reduction of GO sheets under the pressure is one of the effective methods to make well-reduced GO sheets.

  14. High pressure liquid level monitor

    DOE Patents [OSTI]

    Bean, Vern E. (Frederick, MD); Long, Frederick G. (Ijamsville, MD)

    1984-01-01T23:59:59.000Z

    A liquid level monitor for tracking the level of a coal slurry in a high-pressure vessel including a toroidal-shaped float with magnetically permeable bands thereon disposed within the vessel, two pairs of magnetic field generators and detectors disposed outside the vessel adjacent the top and bottom thereof and magnetically coupled to the magnetically permeable bands on the float, and signal processing circuitry for combining signals from the top and bottom detectors for generating a monotonically increasing analog control signal which is a function of liquid level. The control signal may be utilized to operate high-pressure control valves associated with processes in which the high-pressure vessel is used.

  15. Level indicator for pressure vessels

    DOE Patents [OSTI]

    Not Available

    1982-04-28T23:59:59.000Z

    A liquid-level monitor for tracking the level of a coal slurry in a high-pressure vessel including a toroidal-shaped float with magnetically permeable bands thereon disposed within the vessel, two pairs of magnetic-field generators and detectors disposed outside the vessel adjacent the top and bottom thereof and magnetically coupled to the magnetically permeable bands on the float, and signal-processing circuitry for combining signals from the top and bottom detectors for generating a monotonically increasing analog control signal which is a function of liquid level. The control signal may be utilized to operate high-pressure control valves associated with processes in which the high-pressure vessel is used.

  16. SUBNANOWATT MICROBUBBLE PRESSURE TRANSDUCER C. A. Gutierrez*

    E-Print Network [OSTI]

    Meng, Ellis

    pprrr g &&&& 421 2 3 2 (1) where r is the bubble radius (dots denote time-derivative), pg and p microchamber, for pressure sensing. Pressure-induced bubble size variation is detected by electrochemical pressure measurement applications. INTRODUCTION It is known that gas bubbles respond to external pressure

  17. Anyonic statistics with continuous variables

    E-Print Network [OSTI]

    Jing Zhang; Changde Xie; Kunchi Peng; Peter van Loock

    2008-10-30T23:59:59.000Z

    We describe a continuous-variable scheme for simulating the Kitaev lattice model and for detecting statistics of abelian anyons. The corresponding quantum optical implementation is solely based upon Gaussian resource states and Gaussian operations, hence allowing for a highly efficient creation, manipulation, and detection of anyons. This approach extends our understanding of the control and application of anyons and it leads to the possibility for experimental proof-of-principle demonstrations of anyonic statistics using continuous-variable systems.

  18. Variable metric conjugate gradient methods

    SciTech Connect (OSTI)

    Barth, T.; Manteuffel, T.

    1994-07-01T23:59:59.000Z

    1.1 Motivation. In this paper we present a framework that includes many well known iterative methods for the solution of nonsymmetric linear systems of equations, Ax = b. Section 2 begins with a brief review of the conjugate gradient method. Next, we describe a broader class of methods, known as projection methods, to which the conjugate gradient (CG) method and most conjugate gradient-like methods belong. The concept of a method having either a fixed or a variable metric is introduced. Methods that have a metric are referred to as either fixed or variable metric methods. Some relationships between projection methods and fixed (variable) metric methods are discussed. The main emphasis of the remainder of this paper is on variable metric methods. In Section 3 we show how the biconjugate gradient (BCG), and the quasi-minimal residual (QMR) methods fit into this framework as variable metric methods. By modifying the underlying Lanczos biorthogonalization process used in the implementation of BCG and QMR, we obtain other variable metric methods. These, we refer to as generalizations of BCG and QMR.

  19. Reducing uncertainty in geostatistical description with well testing pressure data

    SciTech Connect (OSTI)

    Reynolds, A.C.; He, Nanqun [Univ. of Tulsa, OK (United States); Oliver, D.S. [Chevron Petroleum Technology Company, La Habra, CA (United States)

    1997-08-01T23:59:59.000Z

    Geostatistics has proven to be an effective tool for generating realizations of reservoir properties conditioned to static data, e.g., core and log data and geologic knowledge. Due to the lack of closely spaced data in the lateral directions, there will be significant variability in reservoir descriptions generated by geostatistical simulation, i.e., significant uncertainty in the reservoir descriptions. In past work, we have presented procedures based on inverse problem theory for generating reservoir descriptions (rock property fields) conditioned to pressure data and geostatistical information represented as prior means for log-permeability and porosity and variograms. Although we have shown that the incorporation of pressure data reduces the uncertainty below the level contained in the geostatistical model based only on static information (the prior model), our previous results assumed did not explicitly account for uncertainties in the prior means and the parameters defining the variogram model. In this work, we investigate how pressure data can help detect errors in the prior means. If errors in the prior means are large and are not taken into account, realizations conditioned to pressure data represent incorrect samples of the a posteriori probability density function for the rock property fields, whereas, if the uncertainty in the prior mean is incorporated properly into the model, one obtains realistic realizations of the rock property fields.

  20. Performance of the beam chamber vacuum system of K = 500 cyclotron at Variable Energy Cyclotron Centre Kolkata

    SciTech Connect (OSTI)

    Pal, Gautam, E-mail: gautam.pal@vecc.gov.in; DuttaGupta, Anjan; Chakrabarti, Alok [Variable Energy Cyclotron Centre, I/AF Bidhannagar, Kolkata 700064 (India)

    2014-07-15T23:59:59.000Z

    The beam chamber of Variable Energy Cyclotron Centre, Kolkata's K = 500 superconducting cyclotron is pumped by liquid helium cooled cryopanel with liquid nitrogen cooled radiation shield. Performance of the vacuum system was evaluated by cooling the cryopanel assembly with liquid nitrogen and liquid helium. Direct measurement of beam chamber pressure is quite difficult because of space restrictions and the presence of high magnetic field. Pressure gauges were placed away from the beam chamber. The beam chamber pressure was evaluated using a Monte Carlo simulation software for vacuum system and compared with measurements. The details of the vacuum system, measurements, and estimation of pressure of the beam chamber are described in this paper.

  1. Rate-dependent elastic hysteresis during the peeling of Pressure Sensitive Adhesives

    E-Print Network [OSTI]

    Richard Villey; Costantino Creton; Pierre-Philippe Cortet; Marie-Julie Dalbe; Thomas Jet; Baudouin Saintyves; Stphane Santucci; Loc Vanel; David Yarusso; Matteo Ciccotti

    2015-05-20T23:59:59.000Z

    The modelling of the adherence energy during peeling of Pressure Sensitive Adhesives (PSA) has received much attention since the 1950's, uncovering several factors that aim at explaining their high adherence on most substrates, such as the softness and strong viscoelastic behaviour of the adhesive, the low thickness of the adhesive layer and its confinement by a rigid backing. The more recent investigation of adhesives by probe-tack methods also revealed the importance of cavitation and stringing mechanisms during debonding, underlining the influence of large deformations and of the related non-linear response of the material, which also intervenes during peeling. Although a global modelling of the complex coupling of all these ingredients remains a formidable issue, we report here some key experiments and modelling arguments that should constitute an important step forward. We first measure a non-trivial dependence of the adherence energy on the loading geometry, namely through the influence of the peeling angle, which is found to be separable from the peeling velocity dependence. This is the first time to our knowledge that such adherence energy dependence on the peeling angle is systematically investigated and unambiguously demonstrated. Secondly, we reveal an independent strong influence of the large strain rheology of the adhesives on the adherence energy. We complete both measurements with a microscopic investigation of the debonding region. We discuss existing modellings in light of these measurements and of recent soft material mechanics arguments, to show that the adherence energy during peeling of PSA should not be associated to the propagation of an interfacial stress singularity. The relevant deformation mechanisms are actually located over the whole adhesive thickness, and the adherence energy during peeling of PSA should rather be associated to the energy loss by viscous friction and by rate-dependent elastic hysteresis.

  2. Managed Pressure Drilling Candidate Selection

    E-Print Network [OSTI]

    Nauduri, Anantha S.

    2010-07-14T23:59:59.000Z

    Managed Pressure Drilling now at the pinnacle of the 'Oil Well Drilling' evolution tree, has itself been coined in 2003. It is an umbrella term for a few new drilling techniques and some preexisting drilling techniques, all of them aiming to solve...

  3. Gas Exchange, Partial Pressure Gradients,

    E-Print Network [OSTI]

    Riba Sagarra, Jaume

    Gas Exchange, Partial Pressure Gradients, and the Oxygen Window Johnny E. Brian, Jr., M of circulatory and gas transport physiology, and the best place to start is with normobaric physiology. LIFE affect the precise gas exchange occurring in individual areas of the lungs and body tissues. To make

  4. Atmospheric-pressure plasma jet

    DOE Patents [OSTI]

    Selwyn, Gary S. (Los Alamos, NM)

    1999-01-01T23:59:59.000Z

    Atmospheric-pressure plasma jet. A .gamma.-mode, resonant-cavity plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two concentric cylindrical electrodes are employed to generate a plasma in the annular region therebetween. A "jet" of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly shaping the rf-powered electrode. Because of the atmospheric pressure operation, no ions survive for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike low-pressure plasma sources and conventional plasma processing methods.

  5. Enlarge Image Peer pressure. Magnetic

    E-Print Network [OSTI]

    Thywissen, Joseph

    to stick it to your refrigerator, but an ultra-cold gas magnetizes itself just as do metals such as ironEnlarge Image Peer pressure. Magnetic domains in steel (vertical bans) arise when neighboring electrons point their magnetic poles in the same direction. CREDIT: ZUREKS, CHRIS VARDON

  6. Enlarge Image Peer pressure. Magnetic

    E-Print Network [OSTI]

    Enlarge Image Peer pressure. Magnetic domains in steel (vertical bans) arise when neighboring electrons point their magnetic poles in the same direction. CREDIT: ZUREKS, CHRIS VARDON/WIKIMEDIA By Adrian Cho ScienceNOW Daily News 18 September 2009 It would be tough to stick it to your refrigerator

  7. Quantum Mechanical Pressure Frank Rioux

    E-Print Network [OSTI]

    Rioux, Frank

    by the kinetic theory of gases for an individual gas molecule. #12; Planck's constant. Using de Broglie's equation in the classical expression for kinetic energy converts provides, as we see now, a quantum interpretation for gas pressure. #12;To show this we will consider

  8. Stirling engine with pressurized crankcase

    SciTech Connect (OSTI)

    Corey, John A. (Melrose, NY)

    1988-01-01T23:59:59.000Z

    A two piston Stirling engine wherein the pistons are coupled to a common crankshaft via bearing means, the pistons include pad means to minimize friction between the pistons and the cylinders during reciprocation of the pistons, means for pressurizing the engine crankcase, and means for cooling the crankshaft and the bearing means eliminating the need for oil in the crankcase.

  9. Dynamics of Low-Pressure and High-Pressure Fuel Cell Air Supply System1

    E-Print Network [OSTI]

    Peng, Huei

    comparing the low pressure system with the high- pressure system equipped with a high-speed compressor pressure of the FC that is defined as the pressure at which the reactant hydrogen and oxygen (air) are delivered to the FC stack flow fields. In the case of stored compressed hydrogen the pressure of the cathode

  10. Managing Variability throughout the Software Development Lifecycle

    E-Print Network [OSTI]

    Managing Variability throughout the Software Development Lifecycle Neil Loughran and Awais Rashid levels of the software development lifecycle, especially when new requirements arise. We believe of the software development lifecycle. Moreover, the effects of variability and, in particular, new variabilities

  11. Tailoring Topology Optimization to Composite Pressure Vessel Design with Simultaneous

    E-Print Network [OSTI]

    Paulino, Glaucio H.

    ;Introduction ­ CNG Pressure Vessels Compressed Natural Gas (CNG) Pressure Vessels CNG Cargo Containment System

  12. Gas Permeability of Fractured Sandstone/Coal Samples under Variable Confining Pressure

    E-Print Network [OSTI]

    Liu, Weiqun; Li, Yushou; Wang, Bo

    2010-01-01T23:59:59.000Z

    argillite under con?nement: gas and water testing. Phys.Gascoyne, M. , Wuschke, D.M. : Gas migration through water-fractured rock: results of a gas injection test. J.

  13. Stress-strain characteristics of soils in the variable-confining-pressure triaxial test

    E-Print Network [OSTI]

    O'Brien, Thomas E

    1963-01-01T23:59:59.000Z

    , then the 8 modulus of elasticity in equation (3-3) can be replaced by: E = EI + 2E3 dr (3-1) or "2 + '"3' (3-4) The value of Poisson's ratio, + , has been the subject of con- siderable investigation at the A 6 M College of Texas and elsewhere. Based... , . . . . . . , . . ~ . . . . . . . 1 Ilo PRELIMINARY CONSIDEBATIOMS ~ ~ ~ ~ ~ ~ ~ ~ ~ , ~ ~ ~ ~ 3 Review of Previous Investigations on Stress- Strain Characteristics of Soils and Aggregates. . 4 Theoretical Considerations . . . . . . . . . . . 10 III. PURPOSE OF THE RESBARCH IV...

  14. Ambient pressure fuel cell system

    DOE Patents [OSTI]

    Wilson, Mahlon S. (Los Alamos, NM)

    2000-01-01T23:59:59.000Z

    An ambient pressure fuel cell system is provided with a fuel cell stack formed from a plurality of fuel cells having membrane/electrode assemblies (MEAs) that are hydrated with liquid water and bipolar plates with anode and cathode sides for distributing hydrogen fuel gas and water to a first side of each one of the MEAs and air with reactant oxygen gas to a second side of each one of the MEAs. A pump supplies liquid water to the fuel cells. A recirculating system may be used to return unused hydrogen fuel gas to the stack. A near-ambient pressure blower blows air through the fuel cell stack in excess of reaction stoichiometric amounts to react with the hydrogen fuel gas.

  15. Applications of the Radiation Pressure

    E-Print Network [OSTI]

    Palffy-Muhoray, Peter

    ) of the Sun at the Earth's surface: I = 1.2 kW/m2 The total energy of all photons falling on 1 m2 per 1;12 Theory Photon's energy: E = h (400 pN nm) Photon's momentum: p = h/ Energy and momentum of photon second From Maxwell's equations, the energy density of an EM wave: In terms of irradiance: Pressure P

  16. High pressure xenon ionization detector

    DOE Patents [OSTI]

    Markey, John K. (New Haven, CT)

    1989-01-01T23:59:59.000Z

    A method is provided for detecting ionization comprising allowing particles that cause ionization to contact high pressure xenon maintained at or near its critical point and measuring the amount of ionization. An apparatus is provided for detecting ionization, the apparatus comprising a vessel containing a ionizable medium, the vessel having an inlet to allow high pressure ionizable medium to enter the vessel, a means to permit particles that cause ionization of the medium to enter the vessel, an anode, a cathode, a grid and a plurality of annular field shaping rings, the field shaping rings being electrically isolated from one another, the anode, cathode, grid and field shaping rings being electrically isolated from one another in order to form an electric field between the cathode and the anode, the electric field originating at the anode and terminating at the cathode, the grid being disposed between the cathode and the anode, the field shaping rings being disposed between the cathode and the grid, the improvement comprising the medium being xenon and the vessel being maintained at a pressure of 50 to 70 atmospheres and a temperature of 0.degree. to 30.degree. C.

  17. Scaling of pressurized fluidized beds

    SciTech Connect (OSTI)

    Guralnik, S.; Glicksman, L.R.

    1994-10-01T23:59:59.000Z

    The project has two primary objectives. The first is to verify a set of hydrodynamic scaling relationships for commercial pressurized fluidized bed combustors (PFBC). The second objective is to investigate solids mixing in pressurized bubbling fluidized beds. American Electric Power`s (AEP) Tidd combined-cycle demonstration plant will provide time-varying pressure drop data to serve as the basis for the scaling verification. The verification will involve demonstrating that a properly scaled cold model and the Tidd PFBC exhibit hydrodynamically similar behavior. An important issue in PFBC design is the spacing of fuel feed ports. The feed spacing is dictated by the fuel distribution and the mixing characteristics within the bed. After completing the scaling verification, the cold model will be used to study the characteristics of PFBCs. A thermal tracer technique will be utilized to study mixing both near the fuel feed region and in the far field. The results allow the coal feed and distributor to be designed for optimal heating.

  18. Pressure safety program Lawrence Livermore National Laboratory

    SciTech Connect (OSTI)

    Borzileri, C.; Traini, M.

    1992-10-01T23:59:59.000Z

    The Lawrence Livermore National Laboratory (LLNL) is a Research and Development facility. Programs include research in: nuclear weapons, energy, environmental, biomedical, and other DOE funded programs. LLNL is managed by the University of California for the Department of Energy. Many research and development programs require the use of pressurized fluid systems. In the early 1960`s, courses were developed to train personnel to safely work with pressurized systems. These courses served as a foundation for the Pressure Safety Program. The Pressure Safety Program is administered by the Pressure Safety Manager through the Hazards Control Department, and responsibilities include: (1) Pressure Safety course development and training, (2) Equipment documentation, tracking and inspections/retests, (3) Formal and informal review of pressure systems. The program uses accepted codes and standards and closely follows the DOE Pressure Safety Guidelines Manual. This manual was developed for DOE by Lawrence Livermore National Laboratory. The DOE Pressure Safety Guidelines Manual defines five (5) basic elements which constitute this Pressure Safety Program. These elements are: (1) A Pressure Safety Manual, (2) A Safety Committee, (3) Personnel who are trained and qualified, (4) Documentation and accountability for each pressure vessel or system, (5) Control of the selection and the use of high pressure hardware.

  19. Measuring barometric pressure with a manifold pressure sensor in a microprocessor based engine control system

    SciTech Connect (OSTI)

    Pauwels, M.A.; Wright, D.O.

    1986-07-15T23:59:59.000Z

    A microprocessor based electronic engine control system is described for an internal combustion engine, a method for updating the stored ambient pressure signal by measuring the ambient barometric pressure during engine operation using a manifold pressure sensor. The method consists of: generating timing signals indicating the rotational position of an engine member and including a signal indicating a predetermined rotational position in the rotation of the engine member; generating a pressure signal from the manifold pressure sensor representing the pressure surrounding the sensor in response to the predetermined rotational position; reading the value of ambient barometric pressure stored in the memory of the microprocessor; comparing the value of the barometric pressure stored in the memory of the microprocessor and the value of the pressure signal; increasing the value of the barometric pressure by one unit to generate a new barometric pressure value when the value of the pressure signal is greater than the value of the barometric pressure; comparing the new barometric pressure value with a predetermined fixed constant representing the maximum barometric pressure; and storing in the memory of the microprocessor either the new barometric pressure value if equal to or less than the fixed constant or the value of the maximum barometric pressure if the new barometric pressure value is greater than the fixed constant.

  20. Developing a CD-CBM Anticipatory Approach for Cavitation - Defining a Model-Based Descriptor Consistent Across Processes, Phase 1 Final Report Context-Dependent Prognostics and Health Assessment: A New Paradigm for Condition-based Maintenance SBIR Topic No. N98-114

    SciTech Connect (OSTI)

    Allgood, G.O.; Dress, W.B.; Kercel, S.W.

    1999-06-01T23:59:59.000Z

    The objective of this research, and subsequent testing, was to identify specific features of cavitation that could be used as a model-based descriptor in a context-dependent condition-based maintenance (CD-CBM) anticipatory prognostic and health assessment model. This descriptor is based on the physics of the phenomena, capturing the salient features of the process dynamics. The test methodology and approach were developed to make the cavitation features the dominant effect in the process and collected signatures. This would allow the accurate characterization of the salient cavitation features at different operational states. By developing such an abstraction, these attributes can be used as a general diagnostic for a system or any of its components. In this study, the particular focus will be pumps. As many as 90% of pump failures are catastrophic. They seem to be operating normally and fail abruptly without warning. This is true whether the failure is sudden hardware damage requiring repair, such as a gasket failure, or a transition into an undesired operating mode, such as cavitation. This means that conventional diagnostic methods fail to predict 90% of incipient failures and that in addressing this problem, model-based methods can add value where it is actually needed.

  1. Renewable variable speed hybrid system

    E-Print Network [OSTI]

    Stott, Paul Anthony

    2010-01-01T23:59:59.000Z

    generator island grids, these generators will be running at a fraction of maximum output for most of the time. A new variable speed diesel generator allows for a reduction in fuel consumption at part load compared to constant speed operation. Combining...

  2. Variable Structure Control of a

    E-Print Network [OSTI]

    Ge, Shuzhi Sam

    . INTRODUCTION Modelling and control of flexible link manipulators have been studied intensively controller for regulation of a flexible beam. Due to its simplicity and robustness to parametricVariable Structure Control of a Distributed-Parameter Flexible Beam S. S. Ge,* T. H. Lee, G. Zhu, F

  3. Operating Reserves and Variable Generation

    SciTech Connect (OSTI)

    Ela, E.; Milligan, M.; Kirby, B.

    2011-08-01T23:59:59.000Z

    This report tries to first generalize the requirements of the power system as it relates to the needs of operating reserves. It also includes a survey of operating reserves and how they are managed internationally in system operations today and then how new studies and research are proposing they may be managed in the future with higher penetrations of variable generation.

  4. Pressure Data: BOP Summary 28 May 2010

    Broader source: Energy.gov [DOE]

    This is a schematic of the BOP stack with the static pressure data recoded on the 28th of May and shows pressures before and after the attempted top kill and junk shots.

  5. Effect of high pressure on structural oddities

    E-Print Network [OSTI]

    Johnstone, Russell D. L.

    2010-01-01T23:59:59.000Z

    This thesis describes the effect of pressure on crystal structures that are in some way unusual. The aim was to investigate whether pressure could be used to force these structural oddities to conform to more conventional ...

  6. Nanocomposite Flexible Pressure Sensor for Biomedical Applications

    E-Print Network [OSTI]

    Fachin, F.

    A new approach for the fabrication of flexible pressure sensors based on aligned carbon nanotubes (A-CNTs) is described in this paper. The technology is suitable for blood pressure sensors that can be attached to a stent-graft ...

  7. An investigation of convergence pressure methods

    E-Print Network [OSTI]

    Wattenbarger, Robert Chick

    1986-01-01T23:59:59.000Z

    and subsequent phase behavior calculations, various physical properties of each component are needed. Table 1 lists the physical properties of each of the pure components found in the reservoir fluids. The physical properties of the C7+ must be found..., the pressure at which the K-curves appear to converge to unity is called the apparent convergence pressure. Unless stated otherwise, the convergence pressure of a system implies its apparent convergence pressure. For an N-component, two phase system at a...

  8. High pressure fiber optic sensor system

    SciTech Connect (OSTI)

    Guida, Renato; Xia, Hua; Lee, Boon K; Dekate, Sachin N

    2013-11-26T23:59:59.000Z

    The present application provides a fiber optic sensor system. The fiber optic sensor system may include a small diameter bellows, a large diameter bellows, and a fiber optic pressure sensor attached to the small diameter bellows. Contraction of the large diameter bellows under an applied pressure may cause the small diameter bellows to expand such that the fiber optic pressure sensor may measure the applied pressure.

  9. Carbon nanotube temperature and pressure sensors

    DOE Patents [OSTI]

    Ivanov, Ilia N; Geohegan, David Bruce

    2013-10-29T23:59:59.000Z

    The present invention, in one embodiment, provides a method of measuring pressure or temperature using a sensor including a sensor element composed of a plurality of carbon nanotubes. In one example, the resistance of the plurality of carbon nanotubes is measured in response to the application of temperature or pressure. The changes in resistance are then recorded and correlated to temperature or pressure. In one embodiment, the present invention provides for independent measurement of pressure or temperature using the sensors disclosed herein.

  10. Noninvasive Positive Pressure Ventilation in the Emergency

    E-Print Network [OSTI]

    Noninvasive Positive Pressure Ventilation in the Emergency Department Mei-Ean Yeow, MDa , Jairo I, 1411 East 31st Street, Oakland, CA 94602-1018, USA Noninvasive ventilation is defined as the provision ventilators consist of both negative and positive pressure ventilators. Because negative pressure ventilation

  11. Elec 331 -Blood Pressure Heart Valves

    E-Print Network [OSTI]

    Pulfrey, David L.

    Elec 331 - Blood Pressure 1 Heart Valves Atrio-Ventricular (AV) Bicuspid / Mitral (left - Blood Pressure 2 Phases of the Heart Systole (Max BP) Ventricle contracted Aorta inflated 331 - Blood Pressure 3 Korotkov Phases / Sounds S D P P Nothing Sharp Swish Faint Nothing 0 1 2-3 4 5

  12. WH[eta] under pressure

    SciTech Connect (OSTI)

    Zaleski-Ejgierd, Patryk; Labet, Vanessa; Strobel, Timothy A.; Hoffmann, Roald; Ashcroft, N.W. (Cornell); (CIW)

    2012-05-10T23:59:59.000Z

    An initial observation of the formation of WH under pressure from W gaskets surrounding hydrogen in diamond anvil cells led to a theoretical study of tungsten hydride phases. At P = 1 atm no stoichiometry is found to be stable with respect to separation into the elements, but as the pressure is raised WH{sub n} (n = 1-6, 8) stoichiometries are metastable or stable. WH and WH{sub 4} are calculated to be stable at P > 15 GPa, WH{sub 2} becomes stable at P > 100 GPa and WH{sub 6} at P > 150 GPa. In agreement with experiment, the structure computed for WH is anti-NiAs. WH{sub 2} shares with WH a hexagonal arrangement of tungsten atoms, with hydrogen atoms occupying octahedral and tetrahedral holes. For WH{sub 4} the W atoms are in a distorted fcc arrangement. As the number of hydrogens rises, the coordination of W by H increases correspondingly, leading to a twelve-coordinated W in WH{sub 6}. In WH{sub 8} H{sub 2} units also develop. All of the hydrides considered should be metallic at high pressure, though the Fermi levels of WH{sub 4} and WH{sub 6} lie in a deep pseudogap. Prodded by these theoretical studies, experiments were then undertaken to seek phases other than WH, exploring a variety of experimental conditions that would favor further reaction. Though a better preparation and characterization of WH resulted, no higher hydrides have as yet been found.

  13. Vapor Pressure measurements for dichlorosilane

    E-Print Network [OSTI]

    Morris, Tony Knimbula

    1997-01-01T23:59:59.000Z

    stainless steel surface inside the head. In the user's manual, one of the sections talked about this window and the plugging screw below it. This screw was provided to empty any fluid that might have gotten into that section of the head behind the window... due to being tilted. Immediately afler emptying the fluid, the balance was still unsteady. After allowing the area to dry by leaving the plug off for a few days, the balance readings were stable. It tumed out that the pressure would somehow push...

  14. Reactor pressure vessel vented head

    DOE Patents [OSTI]

    Sawabe, James K. (San Jose, CA)

    1994-01-11T23:59:59.000Z

    A head for closing a nuclear reactor pressure vessel shell includes an arcuate dome having an integral head flange which includes a mating surface for sealingly mating with the shell upon assembly therewith. The head flange includes an internal passage extending therethrough with a first port being disposed on the head mating surface. A vent line includes a proximal end disposed in flow communication with the head internal passage, and a distal end disposed in flow communication with the inside of the dome for channeling a fluid therethrough. The vent line is fixedly joined to the dome and is carried therewith when the head is assembled to and disassembled from the shell.

  15. Electokinetic high pressure hydraulic system

    DOE Patents [OSTI]

    Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA)

    2000-01-01T23:59:59.000Z

    A compact high pressure hydraulic system having no moving parts for converting electric potential to hydraulic force and for manipulating fluids. Electro-osmotic flow is used to provide a valve and means to compress a fluid or gas in a capillary-based system. By electro-osmotically moving an electrolyte between a first position opening communication between a fluid inlet and outlet and a second position closing communication between the fluid inlet and outlet the system can be configured as a valve. The system can also be used to generate forces as large as 2500 psi that can be used to compress a fluid, either a liquid or a gas.

  16. ARM - Lesson Plans: Air Pressure

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow, Alaska Outreach Home RoomPlansPressure

  17. Decreasing Cloudiness Over China: An Updated Analysis Examining Additional Variables

    SciTech Connect (OSTI)

    Kaiser, D.P.

    2000-01-14T23:59:59.000Z

    As preparation of the IPCC's Third Assessment Report takes place, one of the many observed climate variables of key interest is cloud amount. For several nations of the world, there exist records of surface-observed cloud amount dating back to the middle of the 20th Century or earlier, offering valuable information on variations and trends. Studies using such databases include Sun and Groisman (1999) and Kaiser and Razuvaev (1995) for the former Soviet Union, Angel1 et al. (1984) for the United States, Henderson-Sellers (1986) for Europe, Jones and Henderson-Sellers (1992) for Australia, and Kaiser (1998) for China. The findings of Kaiser (1998) differ from the other studies in that much of China appears to have experienced decreased cloudiness over recent decades (1954-1994), whereas the other land regions for the most part show evidence of increasing cloud cover. This paper expands on Kaiser (1998) by analyzing trends in additional meteorological variables for Chi na [station pressure (p), water vapor pressure (e), and relative humidity (rh)] and extending the total cloud amount (N) analysis an additional two years (through 1996).

  18. Pressure transient method for front tracking

    SciTech Connect (OSTI)

    Benson, S.M.; Bodvarsson, G.S.

    1983-08-01T23:59:59.000Z

    A pressure transient technique for tracking the advance of cold water fronts during water flooding and goethermal injection operations has been developed. The technique is based on the concept that the steady state pressure buildup in the reservoir region inside the front can be calculated by a fluid skin factor. By analyzing successive pressure falloff tests, the advance of the front in the reservoir can be monitored. The validity of the methods is demonstrated by application to three numerically simulated data sets, a nonisothermal step-rate injection test, a series of pressure falloffs in a multilayered reservoir, and a series of pressure falloff tests in a water flooded oil reservoir.

  19. Mechanics and Applications of Pressure Adaptive Honeycomb

    E-Print Network [OSTI]

    Vos, Roelof

    2009-07-31T23:59:59.000Z

    calculations. In addition, I would like to express my gratitude to the undergraduate students that have helped with the preparations of the experiments: Lauren Kerth, Will Pflug, Tom O?Brien, Thomas Statsny, and Ryan Barnhart. v TABLE OF CONTENTS... and Curvature Induced by Pressure adaptive Honeycomb 55 3.2.1 Pressure adaptive Wing Section 60 3.2.2 Pressure adaptive Gurney Flap 63 3.2.3 Pressure adaptive Solid State Flap 65 3.2.4 Pressure adaptive Engine Inlet 67 vi 3.3 Actuation Sources 71 4.1 Cellular...

  20. Engine having a high pressure hydraulic system and low pressure lubricating system

    DOE Patents [OSTI]

    Bartley, Bradley E. (Manito, IL); Blass, James R. (Bloomington, IL); Gibson, Dennis H. (Chillicothe, IL)

    2000-01-01T23:59:59.000Z

    An engine includes a high pressure hydraulic system having a high pressure pump and at least one hydraulically-actuated device attached to an engine housing. A low pressure engine lubricating system is attached to the engine housing and includes a circulation conduit fluidly connected to an outlet from the high pressure pump.

  1. Therapeutic Consequences of Variation in Intraarterial Pressure Measurements After Iliac Angioplasty

    SciTech Connect (OSTI)

    Tetteroo, Eric; Haaring, Cees; Engelen, Andries D. van [Department of Radiology, Room E.01.132, University Hospital Utrecht, Heidelberglaan 100, NL-3584 CX Utrecht (Netherlands); Graaf, Yolanda van der [Department of Clinical Epidemiology, University Hospital Utrecht, Heidelberglaan 100, NL-3584 CX Utrecht (Netherlands); Mali, Willem P.T.M. [Department of Radiology, Room E.01.132, University Hospital Utrecht, Heidelberglaan 100, NL-3584 CX Utrecht (Netherlands)

    1997-11-15T23:59:59.000Z

    Purpose: To assess the accuracy of intraarterial measurement of transstenotic pressure gradients for the detection of hemodynamically suboptimal iliac angioplasty. Methods: In 14 patients, referred for diagnostic angiography, mean pressure gradients in the aorta and iliac artery were obtained twice, using a double-sensor pressure catheter. Additional iliac measurements were performed during pharmacologically induced flow augmentation. Repeatability was assessed by calculation of the mean difference plus standard deviation (MD {+-} SD) and repeatability coefficient (2 x SD). These results were extrapolated to 137 iliac angioplasty procedures with secondary stenting where there was a residual pressure gradient > 10 mmHg. Results: MD {+-} SD for repeated measurements at rest and during flow augmentation were 0 {+-} 2 mmHg and 1 {+-} 3 mmHg, respectively. Repeatability coefficients were 3 and 6 mmHg. Mean pressure gradients after hemodynamically insufficient angioplasty were 8 {+-} 7 mmHg at rest and 17 {+-} 5 mmHg following vasodilatation. Inaccurate pressure recordings may have led to inappropriate stent placement in less than 2.5%, and inappropriate denial of stent placement in less than 5% of the lesions. Conclusion: Variability of intraarterial pressure measurements has little consequence in the detection of hemodynamically significant stenosis after angioplasty.

  2. Impact of hydrogen partial pressure on coal liquefaction. Final technical report

    SciTech Connect (OSTI)

    Kang, D.; Hoover, D.S.; Schweighardt, F.K.

    1984-06-01T23:59:59.000Z

    This program was conducted to determine the effects of hydrogen partial pressure on the SRC-I direct coal liquefaction process and SRC-I Demonstration Plant design. A native solvent was produced in quantity and slurried with Kentucky number 9 Mulford coal in a series of coal liquefaction runs under varying hydrogen gas rates, temperatures, residence times, and hydrogen partial pressures. The results showed that hydrogen partial pressure significantly affected product distribution; the magnitude of the effect was comparable to changes in temperature and residence time. Also, the impact of hydrogen partial pressure was enhanced by increases in both temperature and residence time. Operating at low hydrogen partial pressure did not show any apparent advantage; it reduced coal conversion, reduced oil yield, and had a detrimental effect on the yield distribution of other products. An increase in hydrogen partial pressure had the following effects: increased coal conversion; increased conversion of asphaltenes and preasphaltenes to lighter products; significantly increased the oil yield; increased light gas yields; decreased sulfur content in the SRC; increased hydrogen content of the recycle solvent; and increased hydrogen consumption. This study strongly suggests that further studies should be conducted to optimize the effects of hydrogen partial pressure on the process, both within and, preferably, beyond the constraints of the current basic SRC-I design, considering the major impact of this variable on the process. 10 references, 37 figures, 10 tables.

  3. High-pressure microhydraulic actuator

    DOE Patents [OSTI]

    Mosier, Bruce P. (San Francisco, CA) [San Francisco, CA; Crocker, Robert W. (Fremont, CA) [Fremont, CA; Patel, Kamlesh D. (Dublin, CA) [Dublin, CA

    2008-06-10T23:59:59.000Z

    Electrokinetic ("EK") pumps convert electric to mechanical work when an electric field exerts a body force on ions in the Debye layer of a fluid in a packed bed, which then viscously drags the fluid. Porous silica and polymer monoliths (2.5-mm O.D., and 6-mm to 10-mm length) having a narrow pore size distribution have been developed that are capable of large pressure gradients (250-500 psi/mm) when large electric fields (1000-1500 V/cm) are applied. Flowrates up to 200 .mu.L/min and delivery pressures up to 1200 psi have been demonstrated. Forces up to 5 lb-force at 0.5 mm/s (12 mW) have been demonstrated with a battery-powered DC-DC converter. Hydraulic power of 17 mW (900 psi@ 180 uL/min) has been demonstrated with wall-powered high voltage supplies. The force and stroke delivered by an actuator utilizing an EK pump are shown to exceed the output of solenoids, stepper motors, and DC motors of similar size, despite the low thermodynamic efficiency.

  4. Cranial Variability in Amazonian Marmosets

    E-Print Network [OSTI]

    Aguiar, John Marshall

    2011-02-22T23:59:59.000Z

    (Callithrix, Callitrichidae) have been discovered in recent years, as well as the exceptional dwarf marmoset Callibella humilis. Most of these species were described on the basis of their pelage and presumed separation by major rivers. I performed... analyses of craniometric variables by taxa and by river basins, in order to determine if there are significant cranial distinctions between taxa separated by rivers. I analyzed quantitative cranial and mandibular characters of Callibella humilis...

  5. Passive tire pressure sensor and method

    DOE Patents [OSTI]

    Pfeifer, Kent Bryant (Los Lunas, NM); Williams, Robert Leslie (Albuquerque, NM); Waldschmidt, Robert Lee (Calgary, CA); Morgan, Catherine Hook (Ann Arbor, MI)

    2007-09-04T23:59:59.000Z

    A surface acoustic wave device includes a micro-machined pressure transducer for monitoring tire pressure. The device is configured having a micro-machined cavity that is sealed with a flexible conductive membrane. When an external tire pressure equivalent to the cavity pressure is detected, the membrane makes contact with ridges on the backside of the surface acoustic wave device. The ridges are electrically connected to conductive fingers of the device. When the detected pressure is correct, selected fingers on the device will be grounded producing patterned acoustic reflections to an impulse RF signal. When the external tire pressure is less than the cavity reference pressure, a reduced reflected signal to the receiver results. The sensor may further be constructed so as to identify itself by a unique reflected identification pulse series.

  6. Passive tire pressure sensor and method

    DOE Patents [OSTI]

    Pfeifer, Kent Bryant; Williams, Robert Leslie; Waldschmidt, Robert Lee; Morgan, Catherine Hook

    2006-08-29T23:59:59.000Z

    A surface acoustic wave device includes a micro-machined pressure transducer for monitoring tire pressure. The device is configured having a micro-machined cavity that is sealed with a flexible conductive membrane. When an external tire pressure equivalent to the cavity pressure is detected, the membrane makes contact with ridges on the backside of the surface acoustic wave device. The ridges are electrically connected to conductive fingers of the device. When the detected pressure is correct, selected fingers on the device will be grounded producing patterned acoustic reflections to an impulse RF signal. When the external tire pressure is less than the cavity reference pressure, a reduced reflected signal to the receiver results. The sensor may further be constructed so as to identify itself by a unique reflected identification pulse series.

  7. Soot particle aerosol dynamics at high pressure

    SciTech Connect (OSTI)

    Harris, S.J. (General Motors Research Labs., Warren, MI (USA). Physics Dept.); Kennedy, I.M. (California Univ., Davis, CA (USA). Dept. of Mechanical Engineering)

    1989-12-01T23:59:59.000Z

    The authors have used detailed calculations to analyze the coagulation dynamics of a soot aerosol at high pressures (20 and 50 atm). They find that the soot size distribution is altered compared to lower-pressure conditions because the mean free path at high pressures is reduced to the point that the particles are similar in size to the mean free path. At lower pressures the form of the size distribution becomes constant (self-preserving) in time, allowing optical measurements to be easily interpreted. However, the authors find that at pressures above about 5 atm the shape of the size distribution continually changes. As a result, proper and accurate interpretation of optical data at high pressures is more difficult than at lower pressures.

  8. Top Hat Pressure System Hyperbaric Test Analysis | Department...

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

    Top Hat Pressure System Hyperbaric Test Analysis Top Hat Pressure System Hyperbaric Test Analysis This file contains data from pressure measurements inside Top Hat 4....

  9. Variable flexure-based fluid filter

    DOE Patents [OSTI]

    Brown, Steve B.; Colston Jr., Billy W.; Marshall, Graham; Wolcott, Duane

    2007-03-13T23:59:59.000Z

    An apparatus and method for filtering particles from a fluid comprises a fluid inlet, a fluid outlet, a variable size passage between the fluid inlet and the fluid outlet, and means for adjusting the size of the variable size passage for filtering the particles from the fluid. An inlet fluid flow stream is introduced to a fixture with a variable size passage. The size of the variable size passage is set so that the fluid passes through the variable size passage but the particles do not pass through the variable size passage.

  10. Apparatus and method for direct measurement of coal ash sintering and fusion properties at elevated temperatures and pressures

    DOE Patents [OSTI]

    Khan, M. Rashid (Morgantown, WV)

    1990-01-01T23:59:59.000Z

    A high-pressure microdilatometer is provided for measuring the sintering and fusion properties of various coal ashes under the influence of elevated pressures and temperatures in various atmospheres. Electrical resistivity measurements across a sample of coal ash provide a measurement of the onset of the sintering and fusion of the ash particulates while the contraction of the sample during sintering is measured with a linear variable displacement transducer for detecting the initiation of sintering. These measurements of sintering in coal ash at different pressures provide a mechanism by which deleterious problems due to the sintering and fusion of ash in various combustion systems can be minimized or obviated.

  11. Reactor pressure vessel vented head

    DOE Patents [OSTI]

    Sawabe, J.K.

    1994-01-11T23:59:59.000Z

    A head for closing a nuclear reactor pressure vessel shell includes an arcuate dome having an integral head flange which includes a mating surface for sealingly mating with the shell upon assembly therewith. The head flange includes an internal passage extending therethrough with a first port being disposed on the head mating surface. A vent line includes a proximal end disposed in flow communication with the head internal passage, and a distal end disposed in flow communication with the inside of the dome for channeling a fluid therethrough. The vent line is fixedly joined to the dome and is carried therewith when the head is assembled to and disassembled from the shell. 6 figures.

  12. Temperature impacts on the set pressure of soft seated pressure relief valves

    SciTech Connect (OSTI)

    Engel, J.J.; Zirps, G.T.; Gleason, R.B. [and others

    1995-11-01T23:59:59.000Z

    From a safety standpoint, regardless of plant or facility type, the most important pieces of equipment are the pressure relief devices. The most critical characteristics of a pressure relief device are its set pressure and the related relieving capacity. The Set Pressure of a pressure relief device is defined as that value of increasing inlet static pressure at which the discharge becomes continuous (ASME PTC 25-1994, Performance Test Codes). To preclude an unsafe overpressure situation, the set pressure of the pressure relief device must not exceed the maximum allowable working pressure of the equipment or system being protected. Because of testing facility limitations, size or pressure, pressure relief valves intended for elevated temperature service are often set using ambient temperature air. Adjustments are made to the ambient valve opening pressures to compensate for the temperature differences. The extent of the adjustments to the pressure relief valve set pressure is important to ensure the valve will provide the required overpressure protection at the elevated in-service temperature.

  13. Variable Temperature STM/AFM | EMSL

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

    STMAFM Variable Temperature STMAFM EMSL's ultra-high vacuum, variable-temperature scanning probe microscope system, or UHV VT SPM, is a state-of-the-art surface science tool...

  14. Interannual variability in tropospheric nitrous oxide

    E-Print Network [OSTI]

    Thompson, R. L.

    Observations of tropospheric N2O mixing ratio show significant variability on interannual timescales (0.2?ppb, 1 standard deviation). We found that interannual variability in N2O is weakly correlated with that in CFC-12 ...

  15. Thermoacoustic tomography, variable sound speed Plamen Stefanov

    E-Print Network [OSTI]

    Stefanov, Plamen

    Thermoacoustic tomography, variable sound speed Plamen Stefanov Purdue University Based on a joint work with Gunther Uhlmann Plamen Stefanov (Purdue University ) Thermoacoustic tomography, variable sound speed 1 / 18 #12;Formulation Main Problem Thermoacoustic Tomography In thermoacoustic tomography

  16. Portable high precision pressure transducer system

    DOE Patents [OSTI]

    Piper, T.C.; Morgan, J.P.; Marchant, N.J.; Bolton, S.M.

    1994-04-26T23:59:59.000Z

    A high precision pressure transducer system is described for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank. Since the response of the pressure transducer is temperature sensitive, it is continually housed in an battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum fluorescent display. 2 figures.

  17. Portable high precision pressure transducer system

    DOE Patents [OSTI]

    Piper, Thomas C. (Idaho Falls, ID); Morgan, John P. (Idaho Falls, ID); Marchant, Norman J. (Idaho Falls, ID); Bolton, Steven M. (Pocatello, ID)

    1994-01-01T23:59:59.000Z

    A high precision pressure transducer system for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank. Since the response of the pressure transducer is temperature sensitive, it is continually housed in an battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum florescent display.

  18. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN)

    1994-01-01T23:59:59.000Z

    A variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency microwave furnace system (10) includes a microwave signal generator (12) or microwave voltage-controlled oscillator (14) for generating a low-power microwave signal for input to the microwave furnace. A first amplifier (18) may be provided to amplify the magnitude of the signal output from the microwave signal generator (12) or the microwave voltage-controlled oscillator (14). A second amplifier (20) is provided for processing the signal output by the first amplifier (18). The second amplifier (20) outputs the microwave signal input to the furnace cavity (34). In the preferred embodiment, the second amplifier (20) is a traveling-wave tube (TWT). A power supply (22) is provided for operation of the second amplifier (20). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  19. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, D.W.; Lauf, R.J.

    1994-06-14T23:59:59.000Z

    A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

  20. Heating tar sands formations while controlling pressure

    DOE Patents [OSTI]

    Stegemeier, George Leo (Houston, TX) [Houston, TX; Beer, Gary Lee (Houston, TX) [Houston, TX; Zhang, Etuan (Houston, TX) [Houston, TX

    2010-01-12T23:59:59.000Z

    Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. A pressure in the majority of the section may be maintained below a fracture pressure of the formation. The pressure in the majority of the section may be reduced to a selected pressure after the average temperature reaches a temperature that is above 240.degree. C. and is at or below pyrolysis temperatures of hydrocarbons in the section. At least some hydrocarbon fluids may be produced from the formation.

  1. Zirconate pyrochlores under high pressure. | EMSL

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

    phase transformation. Citation: Xiao HY, FX Zhang, F Gao, M Lang, RC Ewing, and WJ Weber.2010."Zirconate pyrochlores under high pressure."Physical Chemistry Chemical Physics....

  2. Elasticity of Materials at High Pressure

    E-Print Network [OSTI]

    Gleason, Arianna Elizabeth

    2010-01-01T23:59:59.000Z

    implications for lower mantle mineralogy, Earth Planet. Sci.C.R. (1998), Lower mantle mineralogy and the geophysical,in Ultrahigh-Pressure Mineralogy: Physics and Chemistry of

  3. Computer-aided analysis of formation pressure integrity tests used in oil well drilling

    SciTech Connect (OSTI)

    Almeida, M.A.

    1986-01-01T23:59:59.000Z

    In this study, the development of a computer simulation model for leak-off tests has been accomplished. This model is more realistic than the one currently used, but is sufficiently simple that it can be applied with data normally available during leak-off test operations in the field. The model includes the many factors that affect pressure behavior during the test, and can predict with reasonable accuracy what the pressure curve will look like. In addition, test interpretation using the computer model is easily achieved using a curve matching technique. The first step toward the development of the computer model was to subdivide the leak-off test into four phases: (1) pressure increase due to overall compressibility of the system, (2) fracture initiation, (3) fracture expansion, and (4) pressure decline and fracture closure after the pump is shut-in. The second step was the development of mathematical models for each phase separately. The mathematical model that predicts pressure increase before fracture initiation includes the most important variables affecting overall compressibility of the system. The modeling of fracture initiation is based on the classical elasticity theory. The modeling of fracture expansion and closure is based on the solution of the continuity equation for flow into a vertical-elliptical fracture with constant height. A computer program that predicts the pressure behavior during the leak-off test was written. This computer model was then verified using field data furnished by Tenneco Oil Company.

  4. Liquid-metal pin-fin pressure drop by correlation in cross flow

    SciTech Connect (OSTI)

    Wang, Zhibi; Kuzay, T.M.; Assoufid, L.

    1994-08-01T23:59:59.000Z

    The pin-fin configuration is widely used as a heat transfer enhancement method in high-heat-flux applications. Recently, the pin-fin design with liquid-metal coolant was also applied to synchrotron-radiation beamline devices. This paper investigates the pressure drop in a pin-post design beamline mirror with liquid gallium as the coolant. Because the pin-post configuration is a relatively new concept, information in literature about pin-post mirrors or crystals is rare, and information about the pressure drop in pin-post mirrors with liquid metal as the coolant is even more sparse. Due to this the authors considered the cross flow in cylinder-array geometry, which is very similar to that of the pin-post, to examine the pressure drop correlation with liquid metals over pin fins. The cross flow of fluid with various fluid characteristics or properties through a tube bank was studied so that the results can be scaled to the pin-fin geometry with liquid metal as the coolant. Study lead to two major variables to influence the pressure drop: fluid properties, viscosity and density, and the relative length of the posts. Correlation of the pressure drop between long and short posts and the prediction of the pressure drop of liquid metal in the pin-post mirror and comparison with an existing experiment are addressed.

  5. Interrelationships between diet, activity, body composition, and blood pressure in elderly subjects

    E-Print Network [OSTI]

    Ideno, Katherine Tamiko

    1987-01-01T23:59:59.000Z

    Independent variables which may influence diastolic blood pressure for groups divided by use of ant i- hypertensive drugs, sex, and activity level . . . . . . 99 LIST OF FIGURES FIGURE Page 1 Scatterplot of dietary protein versus caloric in- take from 24...-hour recall 2 Scatterplot of daily caloric expenditure versus age 42 3 Scatterplot of body weight versus abdominal girth 46 4 Histogram showing distribution of sexes within groups divided by activity and use of anti- hypertensive medication 51 5...

  6. Pressurized fluidized-bed combustion

    SciTech Connect (OSTI)

    Not Available

    1980-10-01T23:59:59.000Z

    The US DOE pressurized fluidized bed combustion (PFBC) research and development program is designed to develop the technology and data base required for the successful commercialization of the PFBC concept. A cooperative program with the US, West Germany, and the UK has resulted in the construction of the 25 MWe IEA-Grimethorpe combined-cycle pilot plant in England which will be tested in 1981. A 13 MWe coal-fired gas turbine (air cycle) at Curtis-Wright has been designed and construction scheduled. Start-up is planned to begin in early 1983. A 75 MWe pilot plant is planned for completion in 1986. Each of these PFBC combined-cycle programs is discussed. The current status of PFB technology may be summarized as follows: turbine erosion tolerance/hot gas cleanup issues have emerged as the barrier technology issues; promising turbine corrosion-resistant materials have been identified, but long-term exposure data is lacking; first-generation PFB combustor technology development is maturing at the PDU level; however, scale-up to larger size has not been demonstrated; and in-bed heat exchanger materials have been identified, but long-term exposure data is lacking. The DOE-PFB development plan is directed at the resolution of these key technical issues. (LCL)

  7. Reactor pressure vessel. Status report

    SciTech Connect (OSTI)

    Elliot, B.J.; Hackett, E.M.; Lee, A.D. [and others

    1996-10-01T23:59:59.000Z

    This report describes the issues raised as a result of the staffs review of Generic Letter (GL) 92-01, Revision 1, responses and plant-specific reactor pressure vessel (RPV) assessments and the actions taken or work in progress to address these issues. In addition, the report describes actions taken by the staff and the nuclear industry to develop a thermal annealing process for use at U.S. commercial nuclear power plants. This process is intended to be used as a means of mitigating the effects of neutron radiation on the fracture toughness of RPV materials. The Nuclear Regulatory Commission (NRC) issued GL 92-01, Revision 1, Supplement 1, to obtain information needed to assess compliance with regulatory requirements and licensee commitments regarding RPV integrity. GL 92-01, Revision 1, Supplement 1, was issued as a result of generic issues that were raised in the NRC staff`s reviews of licensee responses to GL 92-01, Revision 1, and plant-specific RPV evaluations. In particular, an integrated review of all data submitted in response to GL 92-01, Revision 1, indicated that licensees may not have considered all relevant data in their RPV assessments. This report is representative of submittals to and evaluations by the staff as of September 30, 1996. An update of this report will be issued at a later date.

  8. Lightweight bladder lined pressure vessels

    DOE Patents [OSTI]

    Mitlitsky, F.; Myers, B.; Magnotta, F.

    1998-08-25T23:59:59.000Z

    A lightweight, low permeability liner is described for graphite epoxy composite compressed gas storage vessels. The liner is composed of polymers that may or may not be coated with a thin layer of a low permeability material, such as silver, gold, or aluminum, deposited on a thin polymeric layer or substrate which is formed into a closed bladder using tori spherical or near tori spherical end caps, with or without bosses therein, about which a high strength to weight material, such as graphite epoxy composite shell, is formed to withstand the storage pressure forces. The polymeric substrate may be laminated on one or both sides with additional layers of polymeric film. The liner may be formed to a desired configuration using a dissolvable mandrel or by inflation techniques and the edges of the film sealed by heat sealing. The liner may be utilized in most any type of gas storage system, and is particularly applicable for hydrogen, gas mixtures, and oxygen used for vehicles, fuel cells or regenerative fuel cell applications, high altitude solar powered aircraft, hybrid energy storage/propulsion systems, and lunar/Mars space applications, and other applications requiring high cycle life. 19 figs.

  9. Lightweight bladder lined pressure vessels

    DOE Patents [OSTI]

    Mitlitsky, Fred (1125 Canton Ave., Livermore, CA 94550); Myers, Blake (4650 Almond Cir., Livermore, CA 94550); Magnotta, Frank (1206 Bacon Way, Lafayette, CA 94549)

    1998-01-01T23:59:59.000Z

    A lightweight, low permeability liner for graphite epoxy composite compressed gas storage vessels. The liner is composed of polymers that may or may not be coated with a thin layer of a low permeability material, such as silver, gold, or aluminum, deposited on a thin polymeric layer or substrate which is formed into a closed bladder using torispherical or near torispherical end caps, with or without bosses therein, about which a high strength to weight material, such as graphite epoxy composite shell, is formed to withstand the storage pressure forces. The polymeric substrate may be laminated on one or both sides with additional layers of polymeric film. The liner may be formed to a desired configuration using a dissolvable mandrel or by inflation techniques and the edges of the film seamed by heat sealing. The liner may be utilized in most any type of gas storage system, and is particularly applicable for hydrogen, gas mixtures, and oxygen used for vehicles, fuel cells or regenerative fuel cell applications, high altitude solar powered aircraft, hybrid energy storage/propulsion systems, and lunar/Mars space applications, and other applications requiring high cycle life.

  10. The gravitational energy-momentum tensor and the gravitational pressure

    E-Print Network [OSTI]

    J. W. Maluf

    2005-07-28T23:59:59.000Z

    In the framework of the teleparallel equivalent of general relativity it is possible to establish the energy-momentum tensor of the gravitational field. This tensor has the following essential features: (1) it is identified directly in Einstein's field equations; (2) it is conserved and traceless; (3) it yields expressions for the energy and momentum of the gravitational field; (4)it is free of second (and highest) derivatives of the field variables; (5) the gravitational and matter energy-momentum tensors take place in the field equations on the same footing; (6) it is unique. However, it is not symmetric. We show that the spatial components of this tensor yield a consistent definition of the gravitational pressure.

  11. Neurocontrol of Pressurized Water Reactors in Load-Follow Operations

    SciTech Connect (OSTI)

    Lin Chaung; Shen Chihming

    2000-12-15T23:59:59.000Z

    The neurocontrol technique was applied to control a pressurized water reactor (PWR) in load-follow operations. Generalized learning or direct inverse control architecture was adopted in which the neural network was trained off-line to learn the inverse model of the PWR. Two neural network controllers were designed: One provided control rod position, which controlled the axial power distribution, and the other provided the change in boron concentration, which adjusted core total power. An additional feedback controller was designed so that power tracking capability was improved. The time duration between control actions was 15 min; thus, the xenon effect is limited and can be neglected. Therefore, the xenon concentration was not considered as a controller input variable, which simplified controller design. Center target strategy and minimum boron strategy were used to operate the reactor, and the simulation results demonstrated the effectiveness and performance of the proposed controller.

  12. Principal stress pore pressure prediction: utilizing drilling measurements to predict pore pressure

    E-Print Network [OSTI]

    Richardson, Kyle Wade

    2009-05-15T23:59:59.000Z

    A novel method of predicting pore pressure has been invented. The method utilizes currently recorded drilling measurements to predict the pore pressure of the formation through which the bit is drilling. The method applies Mohrs Theory to describe...

  13. Automated high pressure cell for pressure jump x-ray diffraction

    SciTech Connect (OSTI)

    Brooks, Nicholas J.; Gauthe, Beatrice L. L. E.; Templer, Richard H.; Ces, Oscar; Seddon, John M. [Department of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Terrill, Nick J. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Rogers, Sarah E. [ISIS, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom)

    2010-06-15T23:59:59.000Z

    A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ms, both with increasing and decreasing pressures. Pressure is generated by a motorized high pressure pump, and the system is controlled remotely via a graphical user interface to allow operation by a broad user base, many of whom may have little previous experience of high pressure technology. Samples are loaded through a dedicated port allowing the x-ray windows to remain in place throughout an experiment; this facilitates accurate subtraction of background scattering. The system has been designed specifically for use at beamline I22 at the Diamond Light Source, United Kingdom, and has been fully integrated with the I22 beamline control systems.

  14. Variable residence time vortex combustor

    DOE Patents [OSTI]

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

    1987-01-01T23:59:59.000Z

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

  15. Variable delivery, fixed displacement pump

    DOE Patents [OSTI]

    Sommars, Mark F. (Sparland, IL)

    2001-01-01T23:59:59.000Z

    A variable delivery, fixed displacement pump comprises a plurality of pistons reciprocated within corresponding cylinders in a cylinder block. The pistons are reciprocated by rotation of a fixed angle swash plate connected to the pistons. The pistons and cylinders cooperate to define a plurality of fluid compression chambers each have a delivery outlet. A vent port is provided from each fluid compression chamber to vent fluid therefrom during at least a portion of the reciprocal stroke of the piston. Each piston and cylinder combination cooperates to close the associated vent port during another portion of the reciprocal stroke so that fluid is then pumped through the associated delivery outlet. The delivery rate of the pump is varied by adjusting the axial position of the swash plate relative to the cylinder block, which varies the duration of the piston stroke during which the vent port is closed.

  16. Continuously variable focal length lens

    DOE Patents [OSTI]

    Adams, Bernhard W; Chollet, Matthieu C

    2013-12-17T23:59:59.000Z

    A material preferably in crystal form having a low atomic number such as beryllium (Z=4) provides for the focusing of x-rays in a continuously variable manner. The material is provided with plural spaced curvilinear, optically matched slots and/or recesses through which an x-ray beam is directed. The focal length of the material may be decreased or increased by increasing or decreasing, respectively, the number of slots (or recesses) through which the x-ray beam is directed, while fine tuning of the focal length is accomplished by rotation of the material so as to change the path length of the x-ray beam through the aligned cylindrical slows. X-ray analysis of a fixed point in a solid material may be performed by scanning the energy of the x-ray beam while rotating the material to maintain the beam's focal point at a fixed point in the specimen undergoing analysis.

  17. Variable ratio regenerative braking device

    DOE Patents [OSTI]

    Hoppie, Lyle O. (Birmingham, MI)

    1981-12-15T23:59:59.000Z

    Disclosed is a regenerative braking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.

  18. Vapor pressure and boiling point elevation of slash pine black liquors: Predictive models with statistical approach

    SciTech Connect (OSTI)

    Zaman, A.A.; McNally, T.W.; Fricke, A.L. [Univ. of Florida, Gainesville, FL (United States)] [Univ. of Florida, Gainesville, FL (United States)

    1998-01-01T23:59:59.000Z

    Vapor-liquid equilibria and boiling point elevation of slash pine kraft black liquors over a wide range of solid concentrations (up to 85% solids) has been studied. The liquors are from a statistically designed pulping experiment for pulping slash pine in a pilot scale digester with four cooking variables of effective alkali, sulfidity, cooking time, and cooking temperature. It was found that boiling point elevation of black liquors is pressure dependent, and this dependency is more significant at higher solids concentrations. The boiling point elevation data at different solids contents (at a fixed pressure) were correlated to the dissolved solids (S/(1 {minus} S)) in black liquor. Due to the solubility limit of some of the salts in black liquor, a change in the slope of the boiling point elevation as a function of the dissolved solids was observed at a concentration of around 65% solids. An empirical method was developed to describe the boiling point elevation of each liquor as a function of pressure and solids mass fraction. The boiling point elevation of slash pine black liquors was correlated quantitatively to the pulping variables, using different statistical procedures. These predictive models can be applied to determine the boiling point rise (and boiling point) of slash pine black liquors at processing conditions from the knowledge of pulping variables. The results are presented, and their utility is discussed.

  19. NETL- High-Pressure Combustion Research Facility

    ScienceCinema (OSTI)

    None

    2014-06-26T23:59:59.000Z

    NETL's High-Pressure Combustion Facility is a unique resource within the National Laboratories system. It provides the test capabilities needed to evaluate new combustion concepts for high-pressure, high-temperature hydrogen and natural gas turbines. These concepts will be critical for the next generation of ultra clean, ultra efficient power systems.

  20. Pressure Drop in a Pebble Bed Reactor

    E-Print Network [OSTI]

    Kang, Changwoo

    2011-10-21T23:59:59.000Z

    Pressure drops over a packed bed of pebble bed reactor type are investigated. Measurement of porosity and pressure drop over the bed were carried out in a cylindrical packed bed facility. Air and water were used for working fluids. There are several...

  1. Grad-Shafranov equation with anisotropic pressure

    E-Print Network [OSTI]

    V. S. Beskin; I. V. Kuznetsova

    2000-04-16T23:59:59.000Z

    The most general form of the nonrelativistic Grad-Shafranov equation describing anisotropic pressure effects is formulated within the double adiabatic approximation. It gives a possibility to analyze quantitatively how the anisotropic pressure affects the 2D structure of the ideal magnetohydrodynamical flows.

  2. Entropic pressure in lattice models for polymers

    E-Print Network [OSTI]

    Yosi Hammer; Yacov Kantor

    2014-11-20T23:59:59.000Z

    In lattice models local pressure on a surface is derived from the change in the free energy of the system due to the exclusion of a certain boundary site, while the total force on the surface can be obtained by a similar exclusion of all surface sites. In these definitions, while the total force on the surface of a lattice system matches the force measured in a continuous system, the local pressure does not. Moreover, in a lattice system, the sum of the local pressures is not equal to the total force as is required in a continuous system. The difference is caused by correlation between occupations of surface sites as well as finite displacement of surface elements used in the definition of the pressures and the force. This problem is particularly acute in the studies of entropic pressure of polymers represented by random or self-avoiding walks on a lattice. We propose a modified expression for the local pressure which satisfies the proper relation between the pressure and the total force, and show that for ideal polymers in the presence of scale-invariant boundaries it produces quantitatively correct values for continuous systems. The required correction to the pressure is non-local, i.e., it depends on long range correlations between contact points of the polymer and the surface.

  3. NETL- High-Pressure Combustion Research Facility

    SciTech Connect (OSTI)

    None

    2013-07-08T23:59:59.000Z

    NETL's High-Pressure Combustion Facility is a unique resource within the National Laboratories system. It provides the test capabilities needed to evaluate new combustion concepts for high-pressure, high-temperature hydrogen and natural gas turbines. These concepts will be critical for the next generation of ultra clean, ultra efficient power systems.

  4. Energy Management - Using Steam Pressure Efficiently

    E-Print Network [OSTI]

    Jiandani, N.

    1983-01-01T23:59:59.000Z

    Saturated steam contains heat in two different forms. Sensible heat and latent heat. Due to the nature of this vapor, the relative proportion of latent heat is higher at lower pressures compared to higher pressures. When steam is used for heating...

  5. Single stage high pressure centrifugal slurry pump

    DOE Patents [OSTI]

    Meyer, John W. (Palo Alto, CA); Bonin, John H. (Sunnyvale, CA); Daniel, Arnold D. (Alameda, CA)

    1984-03-27T23:59:59.000Z

    Apparatus is shown for feeding a slurry to a pressurized housing. An impeller that includes radial passages is mounted in the loose fitting housing. The impeller hub is connected to a drive means and a slurry supply means which extends through the housing. Pressured gas is fed into the housing for substantially enveloping the impeller in a bubble of gas.

  6. Energy Management - Using Steam Pressure Efficiently

    E-Print Network [OSTI]

    Jiandani, N.

    1983-01-01T23:59:59.000Z

    Saturated steam contains heat in two different forms. Sensible heat and latent heat. Due to the nature of this vapor, the relative proportion of latent heat is higher at lower pressures compared to higher pressures. When steam is used for heating...

  7. Effects of confining pressure, pore pressure and temperature on absolute permeability. SUPRI TR-27

    SciTech Connect (OSTI)

    Gobran, B.D.; Ramey, H.J. Jr.; Brigham, W.E.

    1981-10-01T23:59:59.000Z

    This study investigates absolute permeability of consolidated sandstone and unconsolidated sand cores to distilled water as a function of the confining pressure on the core, the pore pressure of the flowing fluid and the temperature of the system. Since permeability measurements are usually made in the laboratory under conditions very different from those in the reservoir, it is important to know the effect of various parameters on the measured value of permeability. All studies on the effect of confining pressure on absolute permeability have found that when the confining pressure is increased, the permeability is reduced. The studies on the effect of temperature have shown much less consistency. This work contradicts the past Stanford studies by finding no effect of temperature on the absolute permeability of unconsolidated sand or sandstones to distilled water. The probable causes of the past errors are discussed. It has been found that inaccurate measurement of temperature at ambient conditions and non-equilibrium of temperature in the core can lead to a fictitious permeability reduction with temperature increase. The results of this study on the effect of confining pressure and pore pressure support the theory that as confining pressure is increased or pore pressure decreased, the permeability is reduced. The effects of confining pressure and pore pressure changes on absolute permeability are given explicitly so that measurements made under one set of confining pressure/pore pressure conditions in the laboratory can be extrapolated to conditions more representative of the reservoir.

  8. A Simple and Quick Chilled Water Loop Balancing for Variable Flow System

    E-Print Network [OSTI]

    Zhu, Y.; Batten, T.; Turner, W. D.; Claridge, D. E.; Liu, M.

    2000-01-01T23:59:59.000Z

    system is reduced by about 40%. Key words: chilled water, loop, riser, balancing, commissioning, cold deck, pump, energy consumption, EMCS. INTRODUCTION Variable flow pumping systems are becoming more prevalent in the chilled water loops or risers... the building owner, facility engineers or HVAC operators more opportunities to run the chilled water system more efficiently. Generally, the pump speeds are controlled by the EMCS or a stand-alone controller to maintain the differential pressure setpoints...

  9. Flowmeter for pressure-driven chromatography systems

    DOE Patents [OSTI]

    Paul, Phillip H. (Livermore, CA); Arnold, Don W. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    A flowmeter for accurately measuring the flowrate of fluids in high pressure chromatography systems. The flowmeter is a porous bed of a material, the porous bed having a porosity in the range of about 0.1 to 0.6 and a pore size in the range of about 50 nm to 1 .mu.m, disposed between a high pressure pumping means and a chromatography column. The flowmeter is provided with pressure measuring means at both the inlet and outlet of the porous bed for measuring the pressure drop through the porous bed. This flowmeter system provides not only the ability to measure accurately flowrates in the range of .mu.L/min to nL/min but also to provide a signal that can be used for a servo loop or feedback control system for high pressure pumping systems.

  10. Flowmeter for pressure-driven chromatography systems

    DOE Patents [OSTI]

    Paul, Phillip H. (Livermore, CA); Arnold, Don W. (Livermore, CA)

    2003-01-01T23:59:59.000Z

    A flowmeter for accurately measuring the flowrate of fluids in high pressure chromatography systems. The flowmeter is a porous bed of a material, the porous bed having a porosity in the range of about 0.1 to 0.6 and a pore size in the range of about 50 nm to 1 .mu.m, disposed between a high pressure pumping means and a chromatography column. The flowmeter is provided with pressure measuring means at both the inlet and outlet of the porous bed for measuring the pressure drop through the porous bed. This flowmeter system provides not only the ability to measure accurately flowrates in the range of .mu.L/min to nL/min but also to provide a signal that can be used for a servo loop or feedback control system for high pressure pumping systems.

  11. NERC Presentation: Accommodating High Levels of Variable Generation...

    Office of Environmental Management (EM)

    of variable electricity eneration. Variable resources are types of electric power generation that rely on an uncontrolled, "variable" fuel (e.g. wind, sunlight, waves, tidal...

  12. AUTOMATIC VARIABLE VENTILATION CONTROL SYSTEMS BASED ON AIR QUALITY DETECTION

    E-Print Network [OSTI]

    Turiel, Isaac

    2011-01-01T23:59:59.000Z

    ~saon Automatic Variable Ventilation Control Systems Based79-3 Automatic variable ventilation control systems based onof automatic variable ventilation control systems, result in

  13. Field measurement of lateral earth pressures on retaining walls

    E-Print Network [OSTI]

    Riggins, Michael

    1974-01-01T23:59:59.000Z

    . The measured pressures are compared with the computed Coulomb and Rankine pressures for the active case. The measured pressures on the cantilever wall are in close agreement with the theoretical pressures on the upper half of the wall, but the measured... Pressure Variance with Time and Temperature. INTRODUCTION Present Status of the Question -- The latera1 earth pressure theories developed by Coulomb in 1776 and Rankine in 1S57 are known as the classical earth pressure theories (5)*. The basic equation...

  14. Electrochemical cell having improved pressure vent

    DOE Patents [OSTI]

    Dean, Kevin (Pontiac, MI); Holland, Arthur (Troy, MI); Fillmore, Donn (Waterford, MI)

    1993-01-01T23:59:59.000Z

    The electrochemical cell of the instant invention includes a case having a gas outlet, one or more positive electrodes positioned within the case, one or more negative electrodes positioned within the case electrode separators positioned between the positive and negative electrodes, electrolyte positioned within the case, and a pressure vent for releasing internal pressure occurring in the case to the surrounding atmosphere. The pressure vent is affixed to the case covering the gas outlet, the pressure vent includes a vent housing having a hollow interior area in gaseous communication with the surrounding atmosphere and the interior of the case via the gas outlet, a pressure release piston positioned within the hollow interior area, the pressure release piston sized to surround the gas outlet and having a seal groove configured to encapsulate all but one surface of a seal mounted within the seal groove, leaving the non-encapsulated surface of the seal exposed, and a compression spring positioned to urge the pressure release piston to compress the seal in the seal groove and block the gas outlet in the case.

  15. Particle Pressures in Fluidized Beds. Final report

    SciTech Connect (OSTI)

    Campbell, C.S.; Rahman, K.; Jin, C.

    1996-09-01T23:59:59.000Z

    This project studies the particle pressure, which may be thought of as the force exerted by the particulate phase of a multiphase mixture, independently of that exerted by other phases. The project is divided into two parts, one concerning gas and the other liquid fluidized beds. Previous work on gas fluidized beds had suggested that the particle pressures are generated by bubbling action. Thus, for these gas fluidized bed studies, the particle pressure is measured around single bubbles generated in 2-D fluidized beds, using special probes developed especially for this purpose. Liquid beds are immune from bubbling and the particle pressures proved too small to measure directly. However, the major interest in particle pressures in liquid beds lies in their stabilizing effect that arises from the effective elasticity (the derivative of the particle pressure with respect to the void fraction): they impart to the bed. So rather than directly measure the particle pressure, we inferred the values of the elasticity from measurements of instability growth in liquid beds the inference was made by first developing a generic stability model (one with all the normally modeled coefficients left undetermined)and then working backwards to determine the unknown coefficients, including the elasticity.

  16. Particle pressures in fluidized beds. Final report

    SciTech Connect (OSTI)

    Campbell, C.S.; Rahman, K.; Jin, C.

    1996-09-01T23:59:59.000Z

    This project studies the particle pressure, which may be thought of as the force exerted by the particulate phase of a multiphase mixture, independently of that exerted by other phases. The project is divided into two parts, one concerning gas and the other liquid fluidized beds. Previous work on gas fluidized beds had suggested that the particle pressures are generated by bubbling action. Thus, for these gas fluidized bed studies, the particle pressure is measured around single bubbles generated in 2-D fluidized beds, using special probes developed especially for this purpose. Liquid beds are immune from bubbling and the particle pressures proved too small to measure directly. However, the major interest in particle pressures in liquid beds lies in their stabilizing effect that arises from the effective elasticity (the derivative of the particle pressure with respect to the void fraction), they impart to the bed. So rather than directly measure the particle pressure, the authors inferred the values of the elasticity from measurements of instability growth in liquid beds; the inference was made by first developing a generic stability model (one with all the normally modeled coefficients left undetermined) and then working backwards to determine the unknown coefficients, including the elasticity.

  17. Pressure Safety Program Implementation at ORNL

    SciTech Connect (OSTI)

    Lower, Mark [ORNL; Etheridge, Tom [ORNL; Oland, C. Barry [XCEL Engineering, Inc.

    2013-01-01T23:59:59.000Z

    The Oak Ridge National Laboratory (ORNL) is a US Department of Energy (DOE) facility that is managed by UT-Battelle, LLC. In February 2006, DOE promulgated worker safety and health regulations to govern contractor activities at DOE sites. These regulations, which are provided in 10 CFR 851, Worker Safety and Health Program, establish requirements for worker safety and health program that reduce or prevent occupational injuries, illnesses, and accidental losses by providing DOE contractors and their workers with safe and healthful workplaces at DOE sites. The regulations state that contractors must achieve compliance no later than May 25, 2007. According to 10 CFR 851, Subpart C, Specific Program Requirements, contractors must have a structured approach to their worker safety and health programs that at a minimum includes provisions for pressure safety. In implementing the structured approach for pressure safety, contractors must establish safety policies and procedures to ensure that pressure systems are designed, fabricated, tested, inspected, maintained, repaired, and operated by trained, qualified personnel in accordance with applicable sound engineering principles. In addition, contractors must ensure that all pressure vessels, boilers, air receivers, and supporting piping systems conform to (1) applicable American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (2004) Sections I through XII, including applicable code cases; (2) applicable ASME B31 piping codes; and (3) the strictest applicable state and local codes. When national consensus codes are not applicable because of pressure range, vessel geometry, use of special materials, etc., contractors must implement measures to provide equivalent protection and ensure a level of safety greater than or equal to the level of protection afforded by the ASME or applicable state or local codes. This report documents the work performed to address legacy pressure vessel deficiencies and comply with pressure safety requirements in 10 CFR 851. It also describes actions taken to develop and implement ORNLs Pressure Safety Program.

  18. Liquid crystal variable retarders in atomic scattering

    SciTech Connect (OSTI)

    Furst, J.E.; Yu, D.H.; Hayes, P.A.; DSouza, C.M.; Williams, J.F. [Physics Department, Centre for Atomic, Molecular, and Surface Physics, The University of Western Australia, Nedlands. WA. 6907 (Australia)] [Physics Department, Centre for Atomic, Molecular, and Surface Physics, The University of Western Australia, Nedlands. WA. 6907 (Australia)

    1996-11-01T23:59:59.000Z

    The applications of liquid crystal variable retarders in the production of spin-polarized electrons and in the determination of the polarization of optical radiation from atoms excited by polarized electrons are discussed. The advantages of using liquid crystal variable retarders in the measurement of Stokes parameters are insensitivity to the incident photon direction, large transmission diameter, variable retardation over large wavelength range without mechanical movement, and {ital in} {ital situ} calibration. {copyright} {ital 1996 American Institute of Physics.}

  19. Eccentric crank variable compression ratio mechanism

    DOE Patents [OSTI]

    Lawrence, Keith Edward (Kobe, JP); Moser, William Elliott (Peoria, IL); Roozenboom, Stephan Donald (Washington, IL); Knox, Kevin Jay (Peoria, IL)

    2008-05-13T23:59:59.000Z

    A variable compression ratio mechanism for an internal combustion engine that has an engine block and a crankshaft is disclosed. The variable compression ratio mechanism has a plurality of eccentric disks configured to support the crankshaft. Each of the plurality of eccentric disks has at least one cylindrical portion annularly surrounded by the engine block. The variable compression ratio mechanism also has at least one actuator configured to rotate the plurality of eccentric disks.

  20. Eddy current technique for predicting burst pressure

    DOE Patents [OSTI]

    Petri, Mark C. (Yorkville, IL); Kupperman, David S. (Oak Park, IL); Morman, James A. (Woodridge, IL); Reifman, Jaques (Western Springs, IL); Wei, Thomas Y. C. (Downers Grove, IL)

    2003-01-01T23:59:59.000Z

    A signal processing technique which correlates eddy current inspection data from a tube having a critical tubing defect with a range of predicted burst pressures for the tube is provided. The method can directly correlate the raw eddy current inspection data representing the critical tubing defect with the range of burst pressures using a regression technique, preferably an artificial neural network. Alternatively, the technique deconvolves the raw eddy current inspection data into a set of undistorted signals, each of which represents a separate defect of the tube. The undistorted defect signal which represents the critical tubing defect is related to a range of burst pressures utilizing a regression technique.

  1. Pressurized melt ejection into scaled reactor cavities

    SciTech Connect (OSTI)

    Tarbell, W.W.; Pilch, M.; Brockmann, J.E.; Ross, J.W.; Gilbert, D.W.

    1986-10-01T23:59:59.000Z

    This report describes four tests performed in the High-Pressure Melt Streaming Program (HIPS) using linear-scaled cavities of the Zion Nuclear Power Plant. These experiments were conducted to study the phenomena involved in high-pressure ejection of core debris into the cavity beneath the reactor pressure vessel. One-tenth and one-twentieth linear scale models of reactor cavities were constructed and instrumented. The first test used an apparatus constructed of alumina firebrick to minimize the potential interaction between the ejected melt and cavity material. The remaining three experiments used scaled representations of the Zion nuclear plant geometry, constructed of prototypic concrete composition.

  2. RHIC PRESSURE RISE AND ELECTRON CLOUD.

    SciTech Connect (OSTI)

    Zhang, S Y; Blaskiewicz, M; Cameron, P; Drees, P; Afischer, W; Gassner, D; Gullotta, J; He, P; Hseuh, H; Chuang, H; Iriso-Aziz, U; Lee, R; Mackay, W; Woerter, B; Ptitsyn, V; Ponnaiyan, V; Roser, T; Satogata, T; Smart, L; Trbojevic, D

    2003-05-12T23:59:59.000Z

    In RHIC high intensity operation, two types of pressure rise are currently of concern. The first type is at the beam injection, which seems to be caused by the electron multipacting, and the second is the one at the beam transition, where the electron cloud is not the dominant cause. The first type of pressure rise is limiting the beam intensity and the second type might affect the experiments background for very high total beam intensity. In this article, the pressure rises at RHIC are described, and preliminary study results are reported. Some of the unsettled issues and questions are raised, and possible counter measures are discussed.

  3. Pressurized security barrier and alarm system

    DOE Patents [OSTI]

    Carver, D.W.

    1995-04-11T23:59:59.000Z

    A security barrier for placement across a passageway is made up of interconnected pressurized tubing made up in a grid pattern with openings too small to allow passage. The tubing is connected to a pressure switch, located away from the barrier site, which activates an alarm upon occurrence of a pressure drop. A reinforcing bar is located inside and along the length of the tubing so as to cause the tubing to rupture and set off the alarm upon an intruder`s making an attempt to crimp and seal off a portion of the tubing by application of a hydraulic tool. Radial and rectangular grid patterns are disclosed. 7 figures.

  4. Pressure enhanced penetration with shaped charge perforators

    DOE Patents [OSTI]

    Glenn, Lewis A. (Danville, CA)

    2001-01-01T23:59:59.000Z

    A downhole tool, adapted to retain a shaped charge surrounded by a superatmospherically pressurized light gas, is employed in a method for perforating a casing and penetrating reservoir rock around a wellbore. Penetration of a shaped charge jet can be enhanced by at least 40% by imploding a liner in the high pressure, light gas atmosphere. The gas pressure helps confine the jet on the axis of penetration in the latter stages of formation. The light gas, such as helium or hydrogen, is employed to keep the gas density low enough so as not to inhibit liner collapse.

  5. Pressurized security barrier and alarm system

    DOE Patents [OSTI]

    Carver, Don W. (Knoxville, TN)

    1995-01-01T23:59:59.000Z

    A security barrier for placement across a passageway is made up of interconnected pressurized tubing made up in a grid pattern with openings too small to allow passage. The tubing is connected to a pressure switch, located away from the barrier site, which activates an alarm upon occurrence of a pressure drop. A reinforcing bar is located inside and along the length of the tubing so as to cause the tubing to rupture and set off the alarm upon an intruder's making an attempt to crimp and seal off a portion of the tubing by application of a hydraulic tool. Radial and rectangular grid patterns are disclosed.

  6. Variable-Period Undulators For Synchrotron Radiation

    DOE Patents [OSTI]

    Shenoy, Gopal (Naperville, IL); Lewellen, John (Plainfield, IL); Shu, Deming (Darien, IL); Vinokurov, Nikolai (Novosibirsk, RU)

    2005-02-22T23:59:59.000Z

    A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high-energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

  7. Variable Temperature UHV STM/AFM | EMSL

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

    Temperature UHV STMAFM The Omicron variable temperature ultra-high vacuum (UHV) scanning tunneling microscope (VTSTM) is designed to study the structure of both clean and...

  8. Optimization Online - Global Optimization via Slack Variables

    E-Print Network [OSTI]

    Isaac Siwale

    2014-08-01T23:59:59.000Z

    Aug 1, 2014 ... Citation: Siwale, I. (2014). Global optimization via slack variables. Technical Report No. RD-16-2013, London: Apex Research Ltd. Download:...

  9. Pressure induced swelling in microporous materials

    DOE Patents [OSTI]

    Vogt, Thomas; Hriljac, Joseph A.; Lee, Yongjae

    2006-07-11T23:59:59.000Z

    A method for capturing specified materials which includes contacting a microporous material with a hydrostatic fluid having at least one specified material carried therein, under pressure which structurally distorts the lattice sufficiently to permit entry of the at least one specified material. The microporous material is capable of undergoing a temporary structural distortion which alters resting lattice dimensions under increased ambient pressure and at least partially returning to rest lattice dimensions when returned to ambient pressure. The pressure of the fluid is then reduced to permit return to at least partial resting lattice dimension while the at least one specified material is therein. By this method, at least one specified material is captured in the microporous material to form a modified microporous material.

  10. CRAD, Pressurized Systems and Cryogens Assessment Plan

    Broader source: Energy.gov [DOE]

    Assure personnel health and safety through regularly scheduled inspections and maintenance on pressure vessels and equipment, compressed gases and gas cylinders, vacuum equipment and systems, hydraulics, and cryogenic materials and systems.

  11. Pulse Pressure Forming of Lightweight Materials, Development...

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

    Merit Review and Peer Evaluation Meeting, June 7-11, 2010 -- Washington D.C. lm015smith2010o.pdf More Documents & Publications Pulse-Pressure Forming of Lightweight Metals...

  12. Notes 11. High pressure floating ring seals

    E-Print Network [OSTI]

    San Andres, Luis

    2009-01-01T23:59:59.000Z

    Floating ring seals for compressors: leakage and force coefficients, seal lock up and effect on rotor stability, recommendations to reduce seal cross-coupled effects. Long oil seals as pressure barriers in industrial mixers: leakage and force...

  13. High-pressure studies of ammonia hydrates

    E-Print Network [OSTI]

    Wilson, Craig W.

    2014-06-28T23:59:59.000Z

    Ammonia and water are major components of many planetary bodies, from comets and icy moons such as Saturn's Titan to the interiors of the planets Neptune and Uranus. Under a range of high pressures and/or low temperatures known ...

  14. High-pressure synthesis of electronic materials

    E-Print Network [OSTI]

    Penny, George B. S.

    2010-01-01T23:59:59.000Z

    High-pressure techniques have become increasingly important in the synthesis of ceramic and metallic solids allowing the discovery of new materials with interesting properties. In this research dense solid oxides have ...

  15. Pressure Systems Awareness Training | Jefferson Lab

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

    for SAF130A, Pressure Systems Awareness, will be held on February 20 at 11 a.m. in CEBAF Center room F224-225. Registration is available through the Learning Management...

  16. Micromachined pressure sensors: Review and recent developments

    SciTech Connect (OSTI)

    Eaton, W.P.; Smith, J.H. [Sandia National Labs., Albuquerque, NM (United States). Intelligent Micromachines Dept.

    1997-03-01T23:59:59.000Z

    Since the discovery of piezoresistivity in silicon in the mid 1950s, silicon-based pressure sensors have been widely produced. Micromachining technology has greatly benefited from the success of the integrated circuits industry, burrowing materials, processes, and toolsets. Because of this, microelectromechanical systems (MEMS) are now poised to capture large segments of existing sensor markets and to catalyze the development of new markets. Given the emerging importance of MEMS, it is instructive to review the history of micromachined pressure sensors, and to examine new developments in the field. Pressure sensors will be the focus of this paper, starting from metal diaphragm sensors with bonded silicon strain gauges, and moving to present developments of surface-micromachined, optical, resonant, and smart pressure sensors. Considerations for diaphragm design will be discussed in detail, as well as additional considerations for capacitive and piezoresistive devices.

  17. Program predicts two-phase pressure gradients

    SciTech Connect (OSTI)

    Jacks, D.C.; Hill, A.D.

    1983-11-18T23:59:59.000Z

    The calculator program discussed, ORK, was designed for the HP-41CV hand-held calculator and uses the Orkiszewski correlation for predicting 2-phase pressure gradients in vertical tubulars. Accurate predictions of pressure gradients in flowing and gas lift wells over a wide range of well conditions can be obtained with this method, which was developed based on data from 148 wells. The correlation is one of the best generalized 2-phase pressure gradient prediction methods developed to date for vertical flow. It is unique in that hold-up is derived from observed physical phenomena, and the pressure gradient is related to the geometrical distribution of the liquid and gas phase (flow regime).

  18. Low-Pressure Sodium Lighting Basics

    Broader source: Energy.gov [DOE]

    Low-pressure sodium lighting provides more energy-efficient outdoor lighting than high-intensity discharge lighting, but it has very poor color rendition. Typical applications include highway and security lighting, where color is not important.

  19. Injection pressure falloff with flooded zone

    E-Print Network [OSTI]

    Ariadji, Tutuka

    1994-01-01T23:59:59.000Z

    . . . . . . . . . . . . . . . 3 Fracture half-length for the input data of the simulator, 4 Comparisons of static reservoir pressure and reservoir properties of Well No. I after matching with different drainage areas . . . . . . . . . . . . . . . . . . , . 13 13 14 LIST... OF FIGURES Figure I Hazebroek, Rainbow, and Matthews method for determining static Page reservoir pressure 2 Reservoir model 3 Fracture well system 4 Water-oil and gas-oil relative permeability curve data 5 Matching result of Well No. I 15 6 Horner...

  20. Pressure buildup characteristics in Austin Chalk wells

    E-Print Network [OSTI]

    Claycomb, Eddy

    1982-01-01T23:59:59.000Z

    Bottom Hole Pressure Data; Case IV: Most Prevalent Case . 30 VIII Data Used for Analysis of Buildup Test; Case IV 32 LIST OF FIGURES Fi gure Page I Austin Chalk Trend in Texas Horner Plot; Case I: Radial Flow, i. e. , No Hydraulic Fracture 12 III... Pressure 8uildup Test in Vertically Fractured Wells. . . . . . . . . . . . 37 INTRODUCTION The Austin Chalk is a limestone that was deposited during the Gulfian Series of the Cretaceous System. The Austin Chalk overlies the Eagle Ford Group...

  1. PURE NIOBIUM AS A PRESSURE VESSEL MATERIAL

    SciTech Connect (OSTI)

    Peterson, T. J.; Carter, H. F.; Foley, M. H.; Klebaner, A. L.; Nicol, T. H.; Page, T. M.; Theilacker, J. C.; Wands, R. H.; Wong-Squires, M. L.; Wu, G. [Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)

    2010-04-09T23:59:59.000Z

    Physics laboratories around the world are developing niobium superconducting radio frequency (SRF) cavities for use in particle accelerators. These SRF cavities are typically cooled to low temperatures by direct contact with a liquid helium bath, resulting in at least part of the helium container being made from pure niobium. In the U.S., the Code of Federal Regulations allows national laboratories to follow national consensus pressure vessel rules or use of alternative rules which provide a level of safety greater than or equal to that afforded by ASME Boiler and Pressure Vessel Code. Thus, while used for its superconducting properties, niobium ends up also being treated as a material for pressure vessels. This report summarizes what we have learned about the use of niobium as a pressure vessel material, with a focus on issues for compliance with pressure vessel codes. We present results of a literature search for mechanical properties and tests results, as well as a review of ASME pressure vessel code requirements and issues.

  2. Variable Speed Pumping for Level Control

    E-Print Network [OSTI]

    Vasel, M.

    1982-01-01T23:59:59.000Z

    The purpose of this paper is to describe an application of variable speed pumping to level control of an industrial process. Topics include a comparison of the process using control valves with a variable speed system, an energy savings and cost...

  3. THE MULTI-USE STEINEL VARIABLE TEMPERATURE

    E-Print Network [OSTI]

    Kleinfeld, David

    THE MULTI-USE STEINEL VARIABLE TEMPERATURE ELECTRONICALLY CONTROLLED HEAT GUNTEMPERATURE RANGE 212 at the outlet nozzle will bum flesh. Do not tum on Heat Gun with hand in front of nozzle. DO NOT USE NEAR equipment Specifications Temperature Variable from 212" F to 1100 F Watts 1500W Weight 1.5 lbs. Supply

  4. THE MULTI-USE STEINEL VARIABLE TEMPERATURE

    E-Print Network [OSTI]

    Kleinfeld, David

    THE MULTI-USE STEINEL VARIABLE TEMPERATURE ELECTRONICALLY CONTROLLED HEAT GUNTEMPERATURE RANGE 212 at the outlet nozzle will bum flesh. Do not tum on Heat Gun with hand in front of nozzle. DO NOT USE NEAR equipment Specifications Temperature Variable from 212 F to 1100 F Watts 1500W Weight 1.5 lbs. Supply

  5. Solar Dynamics Observatory/ Extreme Ultraviolet Variability Experiment

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    Solar Dynamics Observatory/ EVE Extreme Ultraviolet Variability Experiment Frequently Asked and model solar extreme ultraviolet irradiance variations due to solar flares, solar rotation, and solar and structure of the Sun. What is solar variability? Solar radiation varies on all time scales ranging from

  6. Boosting Search with Variable Elimination. ? Javier Larrosa

    E-Print Network [OSTI]

    Dechter, Rina

    Boosting Search with Variable Elimination. ? Javier Larrosa Dep. Llenguatges i Sistemes Inform#12ElimSearchS;k, a hybrid meta- algorithm that combines search and variable elimination. The param- eter S names from the constraint graph. We also provide experimental evidence that the hybrid algorithm can

  7. Boosting Search with Variable Elimination. ? Javier Larrosa

    E-Print Network [OSTI]

    Dechter, Rina

    Boosting Search with Variable Elimination. ? Javier Larrosa Dep. Llenguatges i Sistemes Inform of variables, reduces the search tree size. In this paper we introduce VarElimSearch(S;k), a hybrid meta the constraint graph. We also provide experimental evidence that the hybrid algorithm can outperform state

  8. Variable Speed Pumping for Level Control

    E-Print Network [OSTI]

    Vasel, M.

    1982-01-01T23:59:59.000Z

    The purpose of this paper is to describe an application of variable speed pumping to level control of an industrial process. Topics include a comparison of the process using control valves with a variable speed system, an energy savings and cost...

  9. Design and fabrication of pressure-compensating compliant tubes

    E-Print Network [OSTI]

    Martin, Ian (Ian P.)

    2014-01-01T23:59:59.000Z

    Different fabrication methods are evaluated for producing pressure-compensating tubes for use in low-pressure drip irrigation systems. Such devices would allow drip irrigation systems to operate at driving pressures much ...

  10. varicose veins smoking obesity swine flu high blood pressure

    E-Print Network [OSTI]

    Diggle, Peter J.

    varicose veins smoking obesity swine flu high blood pressure parkinson's stress depression muscle stiffness heart attack asthma low blood pressure alzheimer's cancer diabetes kidney failure dementia smoking obesity swine flu high blood pressure parkinson's stress depression muscle stiffness heart attack

  11. Nanobubble Collapse on a Silica Surface in Water: Billion-Atom Reactive Molecular Dynamics Simulations

    E-Print Network [OSTI]

    Southern California, University of

    observed in pipes, turbines, pumps, and ship propellers [1­5]. Haines et al. [6] have observed cavitation, Los Angeles, California 90089-0242, USA (Received 19 June 2013; published 31 October 2013) Cavitation generates pressure waves and cavitation bubbles in mercury [7]. Collapse of these bub- bles can cause severe

  12. Discrete Vapour Cavity Model with Improved Timing of Opening and Collapse of Cavities

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    a number of experimental results and corresponding numerical simulations of transient vaporous cavitation@civeng.adelaide.edu.au Abstract Transient vaporous cavitation occurs in hydraulic piping systems when the liquid pressure falls flow can be distinguished: (1) one- component two-phase transient flow (vaporous cavitation; column

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

    SciTech Connect (OSTI)

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

    1997-04-01T23:59:59.000Z

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

  14. Automated High-Pressure Titration System with In Situ Infrared...

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

    High-Pressure Titration System with In Situ Infrared Spectroscopic Detection. Automated High-Pressure Titration System with In Situ Infrared Spectroscopic Detection. Abstract: A...

  15. atmospheric pressure ionization: Topics by E-print Network

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

    for Atmospheric Pressure, in Vivo, and Imaging Mass. For example, atmospheric pressure infrared MALDI (AP IR-MALDI), capable of producing ions from small ionization (DESI),5...

  16. Cylinder Head Gasket with Integrated Combustion Pressure Sensors...

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

    Cylinder Head Gasket with Integrated Combustion Pressure Sensors Cylinder Head Gasket with Integrated Combustion Pressure Sensors Poster presented at the 16th Directions in...

  17. A University Consortium on High Pressure, Lean Combustion for...

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

    High Pressure, Lean Combustion for Efficient and Clean IC Engines (UM - lead, MIT, UCB) A University Consortium on High Pressure, Lean Combustion for Efficient and Clean IC Engines...

  18. asme pressure vessels: Topics by E-print Network

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

    Program & Sensors Hydrogen Delivery Composite Overwrapped Pressure Vessels (COPVs) Pipeline for Off-Board Hydrogen: L-C Atmosphere: 1500 psi H2, ambient pressure Air...

  19. asme pressure vessel: Topics by E-print Network

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

    Program & Sensors Hydrogen Delivery Composite Overwrapped Pressure Vessels (COPVs) Pipeline for Off-Board Hydrogen: L-C Atmosphere: 1500 psi H2, ambient pressure Air...

  20. alloy pressure vessels: Topics by E-print Network

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

    Program & Sensors Hydrogen Delivery Composite Overwrapped Pressure Vessels (COPVs) Pipeline for Off-Board Hydrogen: L-C Atmosphere: 1500 psi H2, ambient pressure Air...

  1. alloy pressure vessel: Topics by E-print Network

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

    Program & Sensors Hydrogen Delivery Composite Overwrapped Pressure Vessels (COPVs) Pipeline for Off-Board Hydrogen: L-C Atmosphere: 1500 psi H2, ambient pressure Air...

  2. aged pressure vessel: Topics by E-print Network

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

    Program & Sensors Hydrogen Delivery Composite Overwrapped Pressure Vessels (COPVs) Pipeline for Off-Board Hydrogen: L-C Atmosphere: 1500 psi H2, ambient pressure Air...

  3. BILIWG Meeting: High Pressure Steam Reforming of Bio-Derived...

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

    High Pressure Steam Reforming of Bio-Derived Liquids (Presentation) BILIWG Meeting: High Pressure Steam Reforming of Bio-Derived Liquids (Presentation) Presented at the 2007...

  4. Achieving 50% ionization efficiency in sub-ambient pressure ionization...

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

    50% ionization efficiency in sub-ambient pressure ionization with nanoelectrospray. Achieving 50% ionization efficiency in sub-ambient pressure ionization with nanoelectrospray....

  5. additional intraocular pressure: Topics by E-print Network

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

    data available in the form of pressure and temperature from new technology like smart plunger. The model is based on fundamental principles of mass conservation and pressure...

  6. High Temperature, High Pressure Devices for Zonal Isolation in...

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

    High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells High Temperature,...

  7. Consider Installing High-Pressure Boilers with BackpressureTurbine...

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

    High-Pressure Boilers with Backpressure Turbine-Generators Consider Installing High-Pressure Boilers with Backpressure Turbine-Generators This tip sheet outlines the benefits of...

  8. Impacts of Rail Pressure and Biodiesel Composition on Soot Nanostructu...

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

    Impacts of Rail Pressure and Biodiesel Composition on Soot Nanostructure Impacts of Rail Pressure and Biodiesel Composition on Soot Nanostructure Fractal dimensions of particle...

  9. advanced high pressure: Topics by E-print Network

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

    interference with increased pressure. We Lee, Tonghun 87 Selection of High Strength Encapsulant for MEMS Devices Undergoing High Pressure Packaging CERN Preprints Summary:...

  10. Dimensional variability of production steel castings

    SciTech Connect (OSTI)

    Peters, F.E.; Risteu, J.W.; Vaupel, W.G.; DeMeter, E.C.; Voigt, R.C.

    1994-12-31T23:59:59.000Z

    Work is ongoing to characterize the dimensional variability of steel casting features. Data are being collected from castings produced at representative Steel Founders` Society of America foundries. Initial results based on more than 12,500 production casting feature measurements are presented for carbon and low alloy steel castings produced in green sand, no-bake, and shell molds. A comprehensive database of casting, pattern, and feature variables has been developed so that the influence of the variables on dimensional variability can be determined. Measurement system analysis is conducted to insure that large measurement error is not reported as dimensional variability. Results indicate that the dimensional variability of production casting features is less than indicated in current US (SFSA) and international (ISO) standards. Feature length, casting weight, parting line and molding process all strongly influence dimensional variability. Corresponding pattern measurements indicate that the actual shrinkage amount for casting features varies considerably. This variation in shrinkage will strongly influence the ability of the foundry to satisfy customer dimensional requirements.

  11. HIGH PRESSURE COAL COMBUSTON KINETICS PROJECT

    SciTech Connect (OSTI)

    Stefano Orsino

    2005-03-30T23:59:59.000Z

    As part of the U.S. Department of Energy (DoE) initiative to improve the efficiency of coal-fired power plants and reduce the pollution generated by these facilities, DOE has funded the High-Pressure Coal Combustion Kinetics (HPCCK) Projects. A series of laboratory experiments were conducted on selected pulverized coals at elevated pressures with the specific goals to provide new data for pressurized coal combustion that will help extend to high pressure and validate models for burnout, pollutant formation, and generate samples of solid combustion products for analyses to fill crucial gaps in knowledge of char morphology and fly ash formation. Two series of high-pressure coal combustion experiments were performed using SRI's pressurized radiant coal flow reactor. The first series of tests characterized the near burner flame zone (NBFZ). Three coals were tested, two high volatile bituminous (Pittsburgh No.8 and Illinois No.6), and one sub-bituminous (Powder River Basin), at pressures of 1, 2, and 3 MPa (10, 20, and 30 atm). The second series of experiments, which covered high-pressure burnout (HPBO) conditions, utilized a range of substantially longer combustion residence times to produce char burnout levels from 50% to 100%. The same three coals were tested at 1, 2, and 3 MPa, as well as at 0.2 MPa. Tests were also conducted on Pittsburgh No.8 coal in CO2 entrainment gas at 0.2, 1, and 2 MPa to begin establishing a database of experiments relevant to carbon sequestration techniques. The HPBO test series included use of an impactor-type particle sampler to measure the particle size distribution of fly ash produced under complete burnout conditions. The collected data have been interpreted with the help of CFD and detailed kinetics simulation to extend and validate devolatilization, char combustion and pollutant model at elevated pressure. A global NOX production sub-model has been proposed. The submodel reproduces the performance of the detailed chemical reaction mechanism for the NBFZ tests.

  12. Effects of gravity and pressure on laminar coflow methaneair diffusion flames at pressures from 1 to 60 atmospheres

    E-Print Network [OSTI]

    Groth, Clinton P. T.

    levels exhibited a similar power- law dependence of the maximum carbon conversion on pressure gravitational acceleration scales with pres- sure-squared, increasing pressure drastically alters the shapes

  13. Apparatus for controlling working gas pressure in Stirling engines

    SciTech Connect (OSTI)

    Tsunekawa, M.; Naito, Y.; Hyodo, M.; Hayashi, T.

    1987-11-17T23:59:59.000Z

    A working gas pressure control apparatus for a Stirling engine is described which comprises: a pressure boost valve provided in a minimum cycle pressure line connected to a working space by a first unidirectional valve; a pressure reducing valve provided in a maximum cycle pressure line connected to the working space by a second unidirectional valve; an operating lever for controlling opening and closing of the pressure boost valve and the pressure reducing valve; a compressor connected by the pressure reducing valve and the pressure boost valves to the cycle pressure lines; an unloading valve arranged in a circuit short-circuiting suction and discharge lines of the compressor; and a control circuit for opening the unloading valve when any one of a rotational speed of the engine falls to a value lower than a present rotational speed for engine idling, the pressure boost valve is opened, and the engine is in a steady-state mode of operation.

  14. Analysis of two basic variables of timeout

    E-Print Network [OSTI]

    Zella, William Francis

    1974-01-01T23:59:59.000Z

    ANALYSIS OF TWO BASIC VARIABLES OF TIMEOUT A Thesis WILLIAM FRANCIS ZELLA Submitted to the Graduate College of Texas AaM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August l974 Major Subjects... Psychology ANALYSI QF TWQ BASIC VARIABLES CF TINEQU '. A Thesis V/ILLIAM FRANCIS ZELLA Approved as to s+yle and content bye Chairman of Commi, ee Head of De artment) (Membe Member) Member ABSTRACT Analysis of Two Basic Variables of Timeout. (August...

  15. We compared the efficacy of positive pressure ventilation (PPV) vs negative pressure ventilation (NPV) in providing

    E-Print Network [OSTI]

    Shadmehr, Reza

    the rationale for the use ofintermittent assisted ventilation is based on the premise that it alleviates muscleWe compared the efficacy of positive pressure ventilation (PPV) vs negative pressure ventilationEMG), minute ventilation (VE),tidal volume (VT), and end-tidal CO (etCO during 15 minutes of PPV and NPV

  16. Atmospheric Pressure Plasma Process And Applications

    SciTech Connect (OSTI)

    Peter C. Kong; Myrtle

    2006-09-01T23:59:59.000Z

    This paper provides a general discussion of atmospheric-pressure plasma generation, processes, and applications. There are two distinct categories of atmospheric-pressure plasmas: thermal and nonthermal. Thermal atmospheric-pressure plasmas include those produced in high intensity arcs, plasma torches, or in high intensity, high frequency discharges. Although nonthermal plasmas are at room temperatures, they are extremely effective in producing activated species, e.g., free radicals and excited state atoms. Thus, both thermal and nonthermal atmosphericpressure plasmas are finding applications in a wide variety of industrial processes, e.g. waste destruction, material recovery, extractive metallurgy, powder synthesis, and energy conversion. A brief discussion of recent plasma technology research and development activities at the Idaho National Laboratory is included.

  17. Pressure balanced drag turbine mass flow meter

    DOE Patents [OSTI]

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

    1982-01-01T23:59:59.000Z

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

  18. Pressure balanced drag turbine mass flow meter

    DOE Patents [OSTI]

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

    1980-04-23T23:59:59.000Z

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

  19. Nuclear Power Plant Containment Pressure Boundary Research

    SciTech Connect (OSTI)

    Cherry, J.L.; Chokshi, N.C.; Costello, J.F.; Ellingwood, B.R.; Naus, D.J.

    1999-09-15T23:59:59.000Z

    Research to address aging of the containment pressure boundary in light-water reactor plants is summarized. This research is aimed at understanding the significant factors relating occurrence of corrosion, efficacy of inspection, and structural capacity reduction of steel containment and liners of concrete containment. This understanding will lead to improvements in risk-informed regulatory decision making. Containment pressure boundary components are described and potential aging factors identified. Quantitative tools for condition assessments of aging structures to maintain an acceptable level of reliability over the service life of the plant are discussed. Finally, the impact of aging (i.e., loss of shell thickness due to corrosion) on steel containment fragility for a pressurized water reactor ice-condenser plant is presented.

  20. Method for noninvasive intracranial pressure measurement

    DOE Patents [OSTI]

    Sinha, Dipen N. (Los Alamos, NM)

    2000-01-01T23:59:59.000Z

    An ultrasonic-based method for continuous, noninvasive intracranial pressure (ICP) measurement and monitoring is described. The stress level in the skull bone is affected by pressure. This also changes the interfacial conditions between the dura matter and the skull bone. Standing waves may be set up in the skull bone and the layers in contact with the bone. At specific frequencies, there are resonance peaks in the response of the skull which can be readily detected by sweeping the excitation frequency on an excitation transducer in contact with a subject's head, while monitoring the standing wave characteristics from the signal received on a second, receiving transducer similarly in contact with the subject's head. At a chosen frequency, the phase difference between the excitation signal and the received signal can be determined. This difference can be related to the intracranial pressure and changes therein.

  1. Polymerization of Formic Acid under High Pressure

    SciTech Connect (OSTI)

    Goncharov, A F; Manaa, M R; Zaug, J M; Fried, L E; Montgomery, W B

    2004-08-23T23:59:59.000Z

    We report combined Raman, infrared (IR) and x-ray diffraction (XRD) measurements, along with ab initio calculations on formic acid under pressure up to 50 GPa. Contrary to the report of Allan and Clark (PRL 82, 3464 (1999)), we find an infinite chain low-temperature Pna2{sub 1} structure consisting of trans molecules to be a high-pressure phase at room temperature. Our data indicate the symmetrization and a partially covalent character of the intra-chain hydrogen bonds above approximately 20 GPa. Raman spectra and XRD patterns indicate a loss of the long-range order at pressures above 40 GPa with a large hysteresis at decompression. We attribute this behavior to a three-dimensional polymerization of formic acid.

  2. High-pressure cell for neutron diffraction with in situ pressure control at cryogenic temperatures

    SciTech Connect (OSTI)

    Jacobsen, Matthew K.; Ridley, Christopher J.; Bocian, Artur; Kamenev, Konstantin V., E-mail: k.kamenev@ed.ac.uk [School of Engineering and CSEC, University of Edinburgh, Edinburgh (United Kingdom); Kirichek, Oleg; Manuel, Pascal; Khalyavin, Dmitry [ISIS, Rutherford Appleton Laboratory, Harwell Oxford (United Kingdom)] [ISIS, Rutherford Appleton Laboratory, Harwell Oxford (United Kingdom); Azuma, Masaki [Materials and Structures Laboratory, Tokyo Institute of Technology, Tokyo (Japan)] [Materials and Structures Laboratory, Tokyo Institute of Technology, Tokyo (Japan); Attfield, J. Paul [School of Chemistry and CSEC, University of Edinburgh, Edinburgh (United Kingdom)] [School of Chemistry and CSEC, University of Edinburgh, Edinburgh (United Kingdom)

    2014-04-15T23:59:59.000Z

    Pressure generation at cryogenic temperatures presents a problem for a wide array of experimental techniques, particularly neutron studies due to the volume of sample required. We present a novel, compact pressure cell with a large sample volume in which load is generated by a bellow. Using a supply of helium gas up to a pressure of 350 bar, a load of up to 78 kN is generated with leak-free operation. In addition, special fiber ports added to the cryogenic center stick allow for in situ pressure determination using the ruby pressure standard. Mechanical stability was assessed using finite element analysis and the dimensions of the cell have been optimized for use with standard cryogenic equipment. Load testing and on-line experiments using NaCl and BiNiO{sub 3} have been done at the WISH instrument of the ISIS pulsed neutron source to verify performance.

  3. UselessVariable Elimination Olin Shivers

    E-Print Network [OSTI]

    Shivers, Olin

    flow analysis on the CPS inter­ mediate form. (I use a CPS representation essentially identical­passing style (CPS) intermediate representations, continuation variables are frequently passed around loops

  4. Continuously-Variable Series-Elastic Actuator

    E-Print Network [OSTI]

    Mooney, Luke M.

    Actuator efficiency is an important factor in the design of powered leg prostheses, orthoses, exoskeletons, and legged robots. A continuously-variable series-elastic actuator (CV-SEA) is presented as an efficient actuator ...

  5. Utility Variable Generation Integration Group Fall Technical...

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

    15, 2014 9:00AM CDT to October 17, 2014 3:00PM CDT The Utility Variable Generation Integration Group (UVIG) Fall Technical Workshop in San Antonio, Texas will provide attendees...

  6. Variable volume architecture : expanding the boundary

    E-Print Network [OSTI]

    Saheba, Asheshh (Asheshh Mohit), 1972-

    2001-01-01T23:59:59.000Z

    Research into the creation of a Variable Volume Architecture is explored through a series of proposals and projects. An argument is established to develop the means and methods of achieving an architecture of transformation. ...

  7. The Cloud Computing and Other Variables

    E-Print Network [OSTI]

    Borjon-Kubota, Martha Estela

    2011-01-01T23:59:59.000Z

    12. Fragments in Six 13. Cloud Computing 14. Phase 15.Note 48. Devoured vi Cloud Computing and other Variables I.moment. Lasts hours. Cloud Computing Just there Over the

  8. High pressure water jet mining machine

    DOE Patents [OSTI]

    Barker, Clark R. (Rolla, MO)

    1981-05-05T23:59:59.000Z

    A high pressure water jet mining machine for the longwall mining of coal is described. The machine is generally in the shape of a plowshare and is advanced in the direction in which the coal is cut. The machine has mounted thereon a plurality of nozzle modules each containing a high pressure water jet nozzle disposed to oscillate in a particular plane. The nozzle modules are oriented to cut in vertical and horizontal planes on the leading edge of the machine and the coal so cut is cleaved off by the wedge-shaped body.

  9. Wind pressure distribution on shell structures

    E-Print Network [OSTI]

    Yancey, Kenneth Earl, Jr

    1963-01-01T23:59:59.000Z

    of calculating wind pressures on buildings is illustrated in the following example: it is desired to find the velocity pressure 35 feet above the ground at Corpus Christi, Texas. The following is known: Anemometer height 42 feet Desired lifetime of structure... at the height of the anemometer, 42 feet, proceed vertically to 98 miles per hour; then 100 90 80 70 60 o 50 ~c 40 g 30 20 40 35 30 25 e 20 3 15 -' o + 10 e 0 9 0 0) 0 z C + 0 0 ) o' 10 20 30 40 50 100 200 300 400 500 Height in Feet...

  10. Ashtekar's New Variables and Positive Energy

    E-Print Network [OSTI]

    James M. Nester; Roh-Suan Tung; Yuan Zhong Zhang

    1994-01-07T23:59:59.000Z

    We discuss earlier unsuccessful attempts to formulate a positive gravitational energy proof in terms of the New Variables of Ashtekar. We also point out the difficulties of a Witten spinor type proof. We then use the special orthonormal frame gauge conditions to obtain a locally positive expression for the New Variables Hamiltonian and thereby a ``localization'' of gravitational energy as well as a positive energy proof.

  11. HVAC's Variable Refrigerant Flow (VRF) Technology

    E-Print Network [OSTI]

    Jones, S.

    2012-01-01T23:59:59.000Z

    1 Comfort by Design Steve Jones Commercial Sales Manager for Mitsubishi Southwest Business Unit HVAC?s Variable Refrigerant Flow (VRF) Technology HVAC Industry Overview HVAC Market Dollar Volume $18 Billion Source:;NABH Research... Moveable Ductless 5 VRF Technology Overview 6 What is VRF Technology? Variable Refrigerant Flow More Comfort, Less Energy Usage 8 INVERTER-driven Compressor Time R oo m T em pe ra tur e ? Enables capacity operation as low as 4% ? Sizing...

  12. Pressure-flow reducer for aerosol focusing devices

    DOE Patents [OSTI]

    Gard, Eric (San Francisco, CA); Riot, Vincent (Oakland, CA); Coffee, Keith (Diablo Grande, CA); Woods, Bruce (Livermore, CA); Tobias, Herbert (Kensington, CA); Birch, Jim (Albany, CA); Weisgraber, Todd (Brentwood, CA)

    2008-04-22T23:59:59.000Z

    A pressure-flow reducer, and an aerosol focusing system incorporating such a pressure-flow reducer, for performing high-flow, atmosphere-pressure sampling while delivering a tightly focused particle beam in vacuum via an aerodynamic focusing lens stack. The pressure-flow reducer has an inlet nozzle for adjusting the sampling flow rate, a pressure-flow reduction region with a skimmer and pumping ports for reducing the pressure and flow to enable interfacing with low pressure, low flow aerosol focusing devices, and a relaxation chamber for slowing or stopping aerosol particles. In this manner, the pressure-flow reducer decouples pressure from flow, and enables aerosol sampling at atmospheric pressure and at rates greater than 1 liter per minute.

  13. Pressurized thermal shock evaluation of the Calvert Cliffs Unit 1 Nuclear Power Plant

    SciTech Connect (OSTI)

    Abbott, L [ed.

    1985-09-01T23:59:59.000Z

    An evaluation of the risk to the Calvert Cliffs Unit 1 nuclear power plant due to pressurized thermal shock (PTS) has been completed by Oak Ridge National Laboratory (ORNL) with the assistance of several other organizations. This evaluation was part of a Nuclear Regulatory Commission program designed to study the PTS risk to three nuclear plants, the other two plants being Oconee Unit 1 and H.B. Robinson Unit 2. The specific objectives of the program were to (1) provide a best estimate of the frequency of a through-the-wall crack in the pressure vessel at each of the three plants, together with the uncertainty in the estimated frequency and its sensitivity to the variables used in the evaluation; (2) determine the dominant overcooling sequences contributing to the estimated frequency and the associated failures in the plant systems or in operator actions; and (3) evaluate the effectiveness of potential corrective measures.

  14. Reactor pressure vessel with forged nozzles

    DOE Patents [OSTI]

    Desai, Dilip R. (Fremont, CA)

    1993-01-01T23:59:59.000Z

    Inlet nozzles for a gravity-driven cooling system (GDCS) are forged with a cylindrical reactor pressure vessel (RPV) section to which a support skirt for the RPV is attached. The forging provides enhanced RPV integrity around the nozzle and substantial reduction of in-service inspection costs by eliminating GDCS nozzle-to-RPV welds.

  15. Pressure-shear experiments on granular materials.

    SciTech Connect (OSTI)

    Reinhart, William Dodd (Sandia National Laboratories, Albuquerque, NM); Thornhill, Tom Finley, III (, Sandia National Laboratories, Albuquerque, NM); Vogler, Tracy John; Alexander, C. Scott (Sandia National Laboratories, Albuquerque, NM)

    2011-10-01T23:59:59.000Z

    Pressure-shear experiments were performed on granular tungsten carbide and sand using a newly-refurbished slotted barrel gun. The sample is a thin layer of the granular material sandwiched between driver and anvil plates that remain elastic. Because of the obliquity, impact generates both a longitudinal wave, which compresses the sample, and a shear wave that probes the strength of the sample. Laser velocity interferometry is employed to measure the velocity history of the free surface of the anvil. Since the driver and anvil remain elastic, analysis of the results is, in principal, straightforward. Experiments were performed at pressures up to nearly 2 GPa using titanium plates and at higher pressure using zirconium plates. Those done with the titanium plates produced values of shear stress of 0.1-0.2 GPa, with the value increasing with pressure. On the other hand, those experiments conducted with zirconia anvils display results that may be related to slipping at an interface and shear stresses mostly at 0.1 GPa or less. Recovered samples display much greater particle fracture than is observed in planar loading, suggesting that shearing is a very effective mechanism for comminution of the grains.

  16. Aerosol Cans? -Aerosol cans use a pressurized

    E-Print Network [OSTI]

    Jia, Songtao

    WHAT TO DO WITH... Aerosol Cans? -Aerosol cans use a pressurized propellant to distribute the product. Propellants are often flammable and/or toxic. Therefore, never store aerosol cans near ignition aerosol cans must be disposed of as hazardous waste. PROPER SAFETY EQUIPMENT Safety Glasses - Proper eye

  17. Pressure grouting of fractured basalt flows

    SciTech Connect (OSTI)

    Shaw, P.; Weidner, J.; Phillips, S.; Alexander, J.

    1996-04-01T23:59:59.000Z

    This report describes a field trial of pressure grouting in basalt and the results of subsequent coring and permeability measurement activities. The objective was to show that the hydraulic conductivity of fractured basalt bedrock can be significantly reduced by pressure injection of cementitious materials. The effectiveness of the pressure grout procedure was evaluated by measuring the change in the hydraulic conductivity of the bedrock. The extent of grout penetration was established by analyzing postgrout injection drilling chips for the presence of a tracer in the grout and also by examining cores of the treated basalt. Downhole radar mapping was used to establish major lava flow patterns and follow water movement during a surface infiltration test. A site called Box Canyon, which is located northwest of the INEL, was chosen for this study due to the similarity of this surface outcrop geology to that of the underlying bedrock fracture system found at the Radioactive Waste Management Complex. This study showed that hydraulic conductivity of basalt can be reduced through pressure grouting of cementitious material.

  18. PRESSURE TRANSIENT ANALYSIS FOR COMPOSITE SYSTEMS

    E-Print Network [OSTI]

    Stanford University

    Financial support was provided through the Stanford Petroleum Research Institute under Department of Energy and Roland N. Home are gratefully acknowledged. Well-test data for Example 10 of Section 7 was provided by Mr. Transient pressure behavior of a well in a two-region composite reservoir has been considered exten- sively

  19. Technical Appendix to Cryogenic Pressure Vessels

    SciTech Connect (OSTI)

    Mulholland, G.T.; Rucinski, R.A; /Fermilab

    1990-02-22T23:59:59.000Z

    The 20,000 gls. Liquid Argon dewar stores up to 15,000 gls. of high purity (<1.0 ppm O{sub 2}, 0.999995) LAr for use in the Liquid Argon calorimeters of E740, the D0 collider detector, at elevation 707-feet. The dewar provides for the total detector volume of 11,000 gls and a 4,000 gls. storage inventory. The large gas volume ({ge}5,000 gls.) serves operational needs and guards against overfill concerns. The LAr dewar functions in two modes: (1) low pressure (16 psi relief) storage, and liquid and gas transfer operations to and from the low pressure (13 psi relief) detector cryostats, and (2) high pressure (65 psi relief) liquid transfer operations to and from a delivery trailer at elevation 743-feet. The storage function is intended to be long term and nonventing. The dewar is equipped with a 40 kW LN{sub 2} condenser that operates to maintain the pressure constant in the storage mode. This service exactly parallels the NeH{sub 2} and D{sub 2} storage dewar services provided at the 15-feet bubble chamber for its operation.

  20. Pressure wave charged repetitively pulsed gas laser

    DOE Patents [OSTI]

    Kulkarny, Vijay A. (Redondo Beach, CA)

    1982-01-01T23:59:59.000Z

    A repetitively pulsed gas laser in which a system of mechanical shutters bracketing the laser cavity manipulate pressure waves resulting from residual energy in the cavity gas following a lasing event so as to draw fresh gas into the cavity and effectively pump spent gas in a dynamic closed loop.