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


1

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

Open Energy Info (EERE)

2-ft Variable Pressure Cavitation Water Tunnel 2-ft Variable Pressure Cavitation Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock 2-ft Variable Pressure Cavitation Water Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Beam(m) 0.6 Depth(m) 0.6 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The 2-Foot Variable Pressure Cavitation Water Tunnel is a vertical plane, closed recirculating, variable-speed, variable-pressure, open jet test section, closed jet test section, and semi-rectangular test section. Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 17 Recirculating Yes

2

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

Open Energy Info (EERE)

Variable Pressure Cavitation Water Tunnel Variable Pressure Cavitation Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock 3-ft Variable Pressure Cavitation Water Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Beam(m) 0.7 Depth(m) 0.7 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The 3-ft Variable Pressure Cavitation Water Tunnel is a vertical plane, closed recirculating with resorber, variable-speed, variable-pressure, two interchangeable circular test sections. Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 25.8 Recirculating Yes Wind Capabilities Wind Capabilities None

3

Analysis of Freeze-Thaw Embolism in Conifers. The Interaction between Cavitation Pressure  

E-Print Network (OSTI)

pressures may expand and cause embolism in the xylem conduits. We used the centrifuge method to evaluate. Under certain con- ditions, these bubbles nucleate cavitation, leading to a gas-filled (embolized

Pittermann, Jarmila

4

Investigation of Potential Concrete Tie Rail Seat Deterioration Mechanisms: Cavitation Erosion and Hydraulic Pressure Cracking  

E-Print Network (OSTI)

Investigation of Potential Concrete Tie Rail Seat Deterioration Mechanisms: Cavitation Erosion and Hydraulic Pressure Cracking 10-2411 Transportation Research Board 89th Annual Meeting Submitted: November 15-2411 1 ABSTRACT Rail seat deterioration (RSD) is the most critical problem with concrete tie performance

Barkan, Christopher P.L.

5

Carderock Large Cavitation Tunnel | Open Energy Information  

Open Energy Info (EERE)

Large Cavitation Tunnel Large Cavitation Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock Large Cavitation Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Length(m) 13.1 Beam(m) 3.0 Depth(m) 3.0 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The Large Cavitation Channel was designed as a variable pressure, recirculating, cavitation tunnel with a very low acoustic background level; test section pressure: 3.5-414 kPa (0.03 to 4 atmospheres, 0.5 to 60 psia); air content: 10% to 100% saturation Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Velocity(m/s) 18 Recirculating Yes Wind Capabilities

6

Variable pressure thermal insulating jacket  

DOE Patents (OSTI)

A device for controlled insulation of a thermal device. 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 communcation 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.

Nelson, Paul A. (Wheaton, IL); Malecha, Richard F. (Naperville, IL); Chilenskas, Albert A. (Chicago, IL)

1994-01-01T23:59:59.000Z

7

Variable pressure thermal insulating jacket  

DOE Patents (OSTI)

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.

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

1994-09-20T23:59:59.000Z

8

Cavitation Erosion  

Science Conference Proceedings (OSTI)

Oct 30, 2013 ... Advances in Hydroelectric Turbine Manufacturing and Repair: Cavitation Erosion Sponsored by: Metallurgical Society of the Canadian Institute ...

9

Variable pressure power cycle and control system  

DOE Patents (OSTI)

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.

Goldsberry, Fred L. (Spring, TX)

1984-11-27T23:59:59.000Z

10

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

E-Print Network (OSTI)

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.

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

2006-09-18T23:59:59.000Z

11

Multi-variable optimization of pressurized oxy-coal combustion  

E-Print Network (OSTI)

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 ...

Zebian, Hussam

2011-01-01T23:59:59.000Z

12

A study of the measurement of cavitation inception using an electrostatic technique  

SciTech Connect

A new concept for detecting cavitation inception has been studied experimentally. In this exploratory study, cavitation is generated by varying the flow velocity and pressure around a circular cylinder. Cavitation inception has been detected by sensing the natural charges and electrification generated during cavitation. The agreement between visual determination and detection using electrostatic probes was quite good. The background and possible mechanisms are reviewed and discussed.

Yuecan, T. (Science and Technology, Wuhan); Velkoff, M.R.

1984-02-01T23:59:59.000Z

13

Characteristic Patterns of Variability of Sea Level Pressure in the Northern Hemisphere  

Science Conference Proceedings (OSTI)

Seasonal and annual mean sea level pressures for the Northern Hemisphere have been analyzed to determine the dominant modes of interannual and longer period variability using monthly sea level pressure analyses as revised by Trenberth and Paolino ...

Kevin E. Trenberth; Daniel A. Paolino Jr.

1981-06-01T23:59:59.000Z

14

Time and Space Variability of Spectral Estimates of Atmospheric Pressure  

Science Conference Proceedings (OSTI)

The purpose of this paper is to analyze the temporal and spatial behavior of atmospheric pressure spectra. The literature shows many examples of pressure, wind and temperature spectra whose shapes display a remarkable degree of universality. ...

Flavio G. Canavero; Franco Einaudi

1987-06-01T23:59:59.000Z

15

Meteorological Variability and the Annual Surface Pressure Cycle on Mars  

Science Conference Proceedings (OSTI)

It is commonly admitted that the seasonal surface pressure cycle, observed on Mars by the two Viking landers, is due to condensation and sublimation of the atmospheric carbon dioxide in the polar caps. A three Martian year numerical simulation ...

Frédéric Hourdin; Phu Le Van; François Forget; Olivier Talagrand

1993-11-01T23:59:59.000Z

16

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

SciTech Connect

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.

Not Available

1991-07-01T23:59:59.000Z

17

The Continuum of North Pacific Sea Level Pressure Patterns: Intraseasonal, Interannual, and Interdecadal Variability  

Science Conference Proceedings (OSTI)

This study combines k-means cluster analysis with linear unidimensional scaling to illustrate the spatial and temporal variability of the wintertime North Pacific sea level pressure (SLP) field. Daily wintertime SLP data derived from the NCEP–...

Nathaniel C. Johnson; Steven B. Feldstein

2010-02-01T23:59:59.000Z

18

Variable pressure insulating jackets for high-temperature batteries  

DOE Green Energy (OSTI)

A new method is proposed for controlling the temperature of high-temperature batteries namely, varying the hydrogen pressure inside of multifoil insulation by varying the temperature of a reversible hydrogen getter. Calculations showed that the rate of heat loss through 1.5 cm of multifoil insulation between a hot-side temperature of 425[degrees]C and a cold-side temperature of 25[degrees]C could be varied between 17.6 W/m[sup 2] and 7,000 W/m[sup 2]. This change in heat transfer rate can be achieved by varying the hydrogen pressure between 1.0 Pa and 1,000 Pa, which can be done with an available hydrogen gettering alloy operating in the range of 50[degrees]C to 250[degrees]C. This approach to battery cooling requires cylindrical insulating jackets, which are best suited for bipolar batteries having round cells approximately 10 to 18 cm in diameter.

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

1992-01-01T23:59:59.000Z

19

Variable pressure insulating jackets for high-temperature batteries  

DOE Green Energy (OSTI)

A new method is proposed for controlling the temperature of high-temperature batteries namely, varying the hydrogen pressure inside of multifoil insulation by varying the temperature of a reversible hydrogen getter. Calculations showed that the rate of heat loss through 1.5 cm of multifoil insulation between a hot-side temperature of 425{degrees}C and a cold-side temperature of 25{degrees}C could be varied between 17.6 W/m{sup 2} and 7,000 W/m{sup 2}. This change in heat transfer rate can be achieved by varying the hydrogen pressure between 1.0 Pa and 1,000 Pa, which can be done with an available hydrogen gettering alloy operating in the range of 50{degrees}C to 250{degrees}C. This approach to battery cooling requires cylindrical insulating jackets, which are best suited for bipolar batteries having round cells approximately 10 to 18 cm in diameter.

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

1992-12-31T23:59:59.000Z

20

Extreme conditions during multibubble cavitation: Sonoluminescence as a spectroscopic probe  

E-Print Network (OSTI)

Cavitation MBSL Plasma a b s t r a c t We review recent work on the use of sonoluminescence (SL) to probe to $9000 K. The effective pressure during MBSL is $300 bar, based on atomic line shifts. Given nanosecond in a liquid, which can create extreme conditions in localized, short- lived hot spots. During the past few

Zimmerman, Steven C.

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


21

Cavitation Measurements on Silicone Oils by Utilization of a Pumping Effect  

Science Conference Proceedings (OSTI)

Characteristic types of cavitation in silicone oils of different gas content and viscosities between 3 and 760 cP have been investigated microscopically and by utilization of a cavitation?pumping effect. The transducer was a 20?kHz stepped horn with a center hole 3 mm in diameter. At hydrostatic pressures between 30 and 760 Torr and transducer amplitudes between 0 and 24 ?

Ernest G. Lierke; Heinz Wollny

1969-01-01T23:59:59.000Z

22

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

E-Print Network (OSTI)

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 system, it can be divided into direct return system pass-by control, direct return system terminal control, reversed return system pass-by control and reversed return system terminal control. The results indicate that reversed return system terminal control has the best hydraulic stability.

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

2006-01-01T23:59:59.000Z

23

joint Spatiotemporal Modes of Surface Temperature and Sea Level Pressure Variability in the Northern Hemisphere during the Last Century  

Science Conference Proceedings (OSTI)

Coherent spatiotemporal modes of climatic variability are isolated based on a multivariate frequency domain singular value decomposition (SVD) of nearly a century of monthly Northern Hemisphere sea level pressure (SLP) and surface temperature ...

Michael E. Mann; Jeffrey Park

1996-09-01T23:59:59.000Z

24

New Insights into North European and North Atlantic Surface Pressure Variability, Storminess, and Related Climatic Change since 1830  

Science Conference Proceedings (OSTI)

The authors present initial results of a new pan-European and international storminess since 1800 as interpreted from European and North Atlantic barometric pressure variability (SENABAR) project. This first stage analyzes results of a new daily ...

Edward Hanna; John Cappelen; Rob Allan; Trausti Jónsson; Frank Le Blancq; Tim Lillington; Kieran Hickey

2008-12-01T23:59:59.000Z

25

Probability density function method for variable-density pressure-gradient-driven turbulence and mixing  

SciTech Connect

Probability density function (PDF) methods are extended to variable-density pressure-gradient-driven turbulence. We apply the new method to compute the joint PDF of density and velocity in a non-premixed binary mixture of different-density molecularly mixing fluids under gravity. The full time-evolution of the joint PDF is captured in the highly non-equilibrium flow: starting from a quiescent state, transitioning to fully developed turbulence and finally dissipated by molecular diffusion. High-Atwood-number effects (as distinguished from the Boussinesq case) are accounted for: both hydrodynamic turbulence and material mixing are treated at arbitrary density ratios, with the specific volume, mass flux and all their correlations in closed form. An extension of the generalized Langevin model, originally developed for the Lagrangian fluid particle velocity in constant-density shear-driven turbulence, is constructed for variable-density pressure-gradient-driven flows. The persistent small-scale anisotropy, a fundamentally 'non-Kolmogorovian' feature of flows under external acceleration forces, is captured by a tensorial diffusion term based on the external body force. The material mixing model for the fluid density, an active scalar, is developed based on the beta distribution. The beta-PDF is shown to be capable of capturing the mixing asymmetry and that it can accurately represent the density through transition, in fully developed turbulence and in the decay process. The joint model for hydrodynamics and active material mixing yields a time-accurate evolution of the turbulent kinetic energy and Reynolds stress anisotropy without resorting to gradient diffusion hypotheses, and represents the mixing state by the density PDF itself, eliminating the need for dubious mixing measures. Direct numerical simulations of the homogeneous Rayleigh-Taylor instability are used for model validation.

Bakosi, Jozsef [Los Alamos National Laboratory; Ristorcelli, Raymond J [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

26

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

SciTech Connect

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)

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

27

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

SciTech Connect

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.

Wiles, Matthew A.; Marriot, Craig D

2013-07-02T23:59:59.000Z

28

Variable pressure supercritical Rankine cycle for integrated natural gas and power production from the geopressured geothermal resource  

DOE Green Energy (OSTI)

A small-scale power plant cycle that utilizes both a variable pressure vaporizer (heater) and a floating pressure (and temperature) air-cooled condenser is described. Further, it defends this choice on the basis of classical thermodynamics and minimum capital cost by supporting these conclusions with actual comparative examples. The application suggested is for the geopressured geothermal resource. The arguments cited in this application apply to any process (petrochemical, nuclear, etc.) involving waste heat recovery.

Goldsberry, F.L.

1982-03-01T23:59:59.000Z

29

Evaluation of CAVIJET cavitating jets for deep-hole rock cutting  

DOE Green Energy (OSTI)

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.

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

1981-05-01T23:59:59.000Z

30

Cavitation-Induced Fusion: Proof of Concept  

E-Print Network (OSTI)

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.

Fomitchev-Zamilov, Max I

2012-01-01T23:59:59.000Z

31

Cavitation-Induced Fusion: Proof of Concept  

E-Print Network (OSTI)

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.

Max I. Fomitchev-Zamilov

2012-09-09T23:59:59.000Z

32

Long-Term Variability of Daily North Atlantic–European Pressure Patterns since 1850 Classified by Simulated Annealing Clustering  

Science Conference Proceedings (OSTI)

Reconstructed daily mean sea level pressure patterns of the North Atlantic–European region are classified for the period 1850 to 2003 to explore long-term changes of the atmospheric circulation and its impact on long-term temperature variability ...

A. Philipp; P. M. Della-Marta; J. Jacobeit; D. R. Fereday; P. D. Jones; A. Moberg; H. Wanner

2007-08-01T23:59:59.000Z

33

GAS-LIQUID-SOLID CAVITATION CHEMISTRY  

Science Conference Proceedings (OSTI)

In this chapter we briefly evaluate the effects of cavitation on the gas-liquid-solid ..... synthesis of A-type zeolites by enabling cheap natural minerals such as kaolin to ..... the aldehyde substrate is adsorbed, whereas under sonochemical ...

34

11 PFLOP/s simulations of cloud cavitation collapse  

Science Conference Proceedings (OSTI)

We present unprecedented, high throughput simulations of cloud cavitation collapse on 1.6 million cores of Sequoia reaching 55% of its nominal peak performance, corresponding to 11 PFLOP/s. The destructive power of cavitation reduces the lifetime of ...

Diego Rossinelli, Babak Hejazialhosseini, Panagiotis Hadjidoukas, Costas Bekas, Alessandro Curioni, Adam Bertsch, Scott Futral, Steffen J. Schmidt, Nikolaus A. Adams, Petros Koumoutsakos

2013-11-01T23:59:59.000Z

35

Twin boundary cavitation in aged type 304 stainless steel  

SciTech Connect

A transition from grain to twin boundary cavitation was observed in aged- and-creep-tested type 304 stainless steel. Evidence of twin boundary cavitation has also been observed for unaged material under certain test conditions. This same behavior was also found in aged type 316 stainless steel. Several possible reasons have been suggested for the absence of frequently observed grain boundary cavitation. (auth)

Sikka, V.K.; Swindeman, R.W.; Brinkman, C.R.

1975-10-01T23:59:59.000Z

36

Cavitation descaling techniques for geothermal applications  

SciTech Connect

A simple and more efficient technique for descaling hard silica scales is urgently needed in order to exploit geothermal energy resources economically. With this objective in mind, DAEDALEAN ASSOCIATES, Incorporated is engaged in a research and development program utilizing the phenomenon of cavitation for cleaning and descaling under the sponsorship of ERDA, Division of Geothermal Research. The highlights of the research carried out so far under this program is reviewed in this presentation. Various effects of the phenomenon of cavitation erosion are presented. The intensity of cavitation erosion and its use in descaling applications are explained. The parameters governing the intensity of erosion are discussed. The overall objectives of the program are to demonstrate the engineering feasibility of utilizing cavitation and to generate engineering design data for its application in geothermal technology. The test facility used for this research consists of flow equipment, test chamber, and associated instrumentation. The performance of cavitating nozzles have been evaluated over a range of sizes. The intensity of erosion for one specific nozzle has been measured. The cleaning rates, the quality of cleaned surface and the intensity margin available so as not to damage the pipe wall have been determined for this specific design. Further work is under progress.

Thiruvengadam, Alagu P.

1976-01-01T23:59:59.000Z

37

Throttled Valve Cavitation and Erosion  

E-Print Network (OSTI)

The submitted manuscipt has been authored by a contmrctor of the US. Government under contract No. DE-AC05-840R21400. Accordingly, the U. S. Government retains a nonexclusive royalty-free license to publish or reproduce the published form of the contribution, or aflow others to do so, for US. Government pupose & 1. Background In November of 1988, Brunswick plant maintenance personnel discovered significant localized erosion of the valve body of a Unit I Residual Heat Removal (RHR) valve, 1-El 1-F017B (the maintenance was being performed to repair the valve stem and back seat). 1 The F017B valv'e is a 20-inch Rockwell angle globe valve that has been historically used to throttle RHR flow. Excessive throttling of the valve had resulted in cavitation-induced erosion damage to areas immediately downstream of the seat. Subsequent investigation indicated that erosion of valve bodies was a generic concern for the other RHR valves used in the same service (FO17A on Unit I and F017A and F017B on Unit 2). Brunswick personnel expanded the investigation to include another set of RHR valves that had also been used in throttling service. The F024A and F024B valves (from both Units), which are used for Suppression Pool Cooling, were also found to have been damaged by

Don Casada; Don Casada

1991-01-01T23:59:59.000Z

38

MHL High Speed Cavitation | Open Energy Information  

Open Energy Info (EERE)

High Speed Cavitation High Speed Cavitation Jump to: navigation, search Basic Specifications Facility Name MHL High Speed Cavitation Overseeing Organization University of Michigan Hydrodynamics Hydrodynamic Testing Facility Type Channel Length(m) 0.8 Beam(m) 0.2 Depth(m) 0.2 Cost(per day) $2000(+ Labor/Materials) Towing Capabilities Towing Capabilities Yes Maximum Velocity(m/s) 25.9 Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 25.9 Recirculating No Wind Capabilities Wind Capabilities None Control and Data Acquisition Description Custom Data Acquisition System using National Instruments hardware; system compatible with Planing Hull and Floating Beam Dynamometers Number of channels 16 Bandwidth(kHz) 20 Cameras Yes

39

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

E-Print Network (OSTI)

of Fractured Sandstone/Coal Samples Smeulders, D.M.J. ,stress on permeability of coal. Int. J. Rock Mech. Min. Sci.of Fractured Sandstone/Coal Samples under Variable Con?ning

Liu, Weiqun; Li, Yushou; Wang, Bo

2010-01-01T23:59:59.000Z

40

Developing a CD-CBM Anticipatory Approach for Cavitation - Defining a Model Descriptor Consistent Between Processes  

Science Conference Proceedings (OSTI)

A major problem with cavitation in pumps and other hydraulic devices is that there is no effective method for detecting or predicting its inception. The traditional approach is to declare the pump in cavitation when the total head pressure drops by some arbitrary value (typically 3o/0) in response to a reduction in pump inlet pressure. However, the pump is already cavitating at this point. A method is needed in which cavitation events are captured as they occur and characterized by their process dynamics. The object of this research 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 was based on the physics of the phenomena, capturing the salient features of the process dynamics. An important element of this concept is the development and formulation of the extended process feature vector @) or model vector. Thk model-based descriptor encodes the specific information that describes the phenomena and its dynamics and is formulated as a data structure consisting of several elements. The first is a descriptive model abstracting the phenomena. The second is the parameter list associated with the functional model. The third is a figure of merit, a single number between [0,1] representing a confidence factor that the functional model and parameter list actually describes the observed data. Using this as a basis and applying it to the cavitation problem, any given location in a flow loop will have this data structure, differing in value but not content. The extended process feature vector is formulated as follows: E`> [ , {parameter Iist}, confidence factor]. (1) For this study, the model that characterized cavitation was a chirped-exponentially decaying sinusoid. Using the parameters defined by this model, the parameter list included frequency, decay, and chirp rate. Based on this, the process feature vector has the form: @=> [, {01 = a, ~= b, ~ = c}, cf = 0.80]. (2) In this experiment a reversible catastrophe was examined. The reason for this is that the same catastrophe could be repeated to ensure the statistical significance of the data.

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

1999-05-10T23:59:59.000Z

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


41

HEART RATE AND BLOOD PRESSURE VARIABILITY UNDER MOON, MARS AND ZERO GRAVITY CONDITIONS DURING PARABOLIC FLIGHTS  

E-Print Network (OSTI)

PARABOLIC FLIGHTS Wouter Aerts1 , Pieter Joosen1 , Devy Widjaja1,2 , Carolina Varon1,2 , Steven Vandeput1 Leuven, Belgium, Email: andre.aubert@med.kuleuven.be ABSTRACT Gravity changes during partial-G parabolic to reduce postflight orthostatic intolerance. Key words: parabolic flight; heart rate; blood pressure

42

Enhancement in Surface Atmospheric Pressure Variability Associated with a Major Geomagnetic Storm  

E-Print Network (OSTI)

Observational studies indicate that there is a close association between geomagnetic storm and meteorological parameters. Geomagnetic field lines follow closely the isobars of surface pressure . A Physical mechanism linking upper atmospheric geomagnetic storm disturbances with tropospheric weather has been proposed by the author and her group where it is postulated that vertical mixing by turbulent eddy fluctuations results in the net transport upward of positive charges originating from lower levels accompanied simultaneously by downward flow of negative charges from higher levels. The present study reports enhancement of high frequency (geomagnetic storm (Ap index = 246) on 13 march 1989.

A. M. Selvam; S. Fadnavis; S. U. Athale; M. I. R. Tinmaker

1998-07-03T23:59:59.000Z

43

W-11: Combined Cavitation and Particle Erosion of Brass  

Science Conference Proceedings (OSTI)

A novel method is employed that combines the effect of particle erosion and cavitation erosion, in order to test brass under laboratory conditions. Triangular ...

44

Hydrogen Attack in Creeping Polycrystals Due to Cavitation on ...  

Science Conference Proceedings (OSTI)

Sep 1, 1994 ... Hydrogen Attack (HA) is the development at elevated temperatures of grain boundary cavitation by internal methane gas, which is generated by ...

45

Molecular Dynamics Simulation of Cavitation in Metallic Glass  

Science Conference Proceedings (OSTI)

We have undertaken a series of molecular dynamics simulations of cavitation under hydrostatic tension in a binary metallic glass analog using pair-wise ...

46

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

E-Print Network (OSTI)

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. As the commissioning process has begun to require the prediction of savings, knowledge of the extent to which various SPR control strategies impact fan energy has become increasingly important. This research aims to document existing SPR control strategies and utilize building data and simulation to estimate fan energy use. A comprehensive review of the literature pertaining to SPR control was performed and the results were organized into a top-down flow chart tool. Based on the type of feedback available from a particular system, or lack thereof, this tool will facilitate the selection of a SPR control strategy. A field experiment was conducted on a single duct variable air volume system with fixed discharge air temperature and static pressure setpoints. Finally, an air-side model of the experimental system was created using detailed building design information and calibrated using field measurements. This model was used to estimate the fan energy required to supply the trended airflow data using fixed static pressure (FSP) and SPR control based on zone demand, system demand, and outside air temperature. While utilizing trend data from November 1, 2008 to February 12, 2009, the FSP control of the experimental system was used as the baseline for ranking the energy savings potential of nine different forms of duct static pressure control. The highest savings (73-74%) were achieved using zonal demand based SPR control. System demand based SPR control yielded savings ranging from 59 to 76%, which increased when the duct sensor was positioned near the fan discharge and under similar zone load conditions. The outside air temperature based SPR control yielded savings of 65% since the experimental system supplied primarily perimeter zones. Finally, increasing the FSP setpoint from 2 to 3 inWG increased fan energy by 45%, while decreasing the setpoint from 2 to 1 inWG decreased fan energy by 41%.

Kimla, John

2009-12-01T23:59:59.000Z

47

In-cylinder pressure and inter-cycle variability analysis for a compression ignition engine : Bayesian approaches.  

E-Print Network (OSTI)

??This thesis introduced Bayesian statistics as an analysis technique to isolate resonant frequency information in in-cylinder pressure signals taken from internal combustion engines. Applications of… (more)

Bodisco, Timothy Alexis

2013-01-01T23:59:59.000Z

48

Chemical Applications of Electrohydraulic Cavitation for Hazardous Waste Control  

E-Print Network (OSTI)

We have been investigating the fundamental chemistry and physics underlying the application of electrohydraulic cavitation as induced by pulsed-power plasma discharge in water, by spark-gap discharge in water (i.e., lithotripsy) and by pulsed (and/or continuous) ultrasonic irradiation (i.e., sonolysis) of water for the elimination of chlorinated hydrocarbons from water. These three different applications of electric power share a common physical thread, which involves hydraulic cavitation, production of shock waves, release of high energy light, 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.

Hoffmann, M. R.

1992-04-01T23:59:59.000Z

49

Cavitation contributes substantially to tensile creep in silicon nitride  

Science Conference Proceedings (OSTI)

During tensile creep of a hot isostatically pressed (HIPed) silicon nitride, the volume fraction of cavities increases linearly with strain; these cavities produce nearly all of the measured strain. In contrast, compressive creep in the same stress and temperature range produces very little cavitation. A stress exponent that increases with stress ({dot {var_epsilon}} {proportional_to} {sigma}{sup n}, 2 < n < 7) characterizes the tensile creep response, while the compressive creep response exhibits a stress dependence of unity. Furthermore, under the same stress and temperature, the material creeps nearly 100 times faster in tension than in compression. Transmission electron microscopy (TEM) indicates that the cavities formed during tensile creep occur in pockets of residual crystalline silicate phase located at silicon nitride multigrain junctions. Small-angle X-ray scattering (SAXS) from crept material quantifies the size distribution of cavities observed in TEM and demonstrates that cavity addition, rather than cavity growth, dominates the cavitation process. These observations are in accord with a model for creep based on the deformation of granular materials in which the microstructure must dilate for individual grains t slide past one another. During tensile creep the silicon nitride grains remain rigid; cavitation in the multigrain junctions allows the silicate to flow from cavities to surrounding silicate pockets, allowing the dilation of the microstructure and deformation of the material. Silicon nitride grain boundary sliding accommodates this expansion and leads to extension of the specimen. In compression, where cavitation is suppressed, deformation occurs by solution-reprecipitation of silicon nitride.

Luecke, W.E.; Wiederhorn, S.M.; Hockey, B.J.; Krause, R.F. Jr.; Long, G.G. [National Institute of Standards and Technology, Gaithersburg, MD (United States)

1995-08-01T23:59:59.000Z

50

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

SciTech Connect

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.

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

2008-02-15T23:59:59.000Z

51

Measurements of Sea Surface Height Variability in the Eastern South Atlantic from Pressure Sensor–Equipped Inverted Echo Sounders: Baroclinic and Barotropic Components  

Science Conference Proceedings (OSTI)

Variability in sea surface height (SSH) can be decomposed into two contributions: one from changes in mass in the water column (barotropic) and the other from purely steric changes (baroclinic). Both contributions can be determined from data ...

Sheekela Baker-Yeboah; D. Randolph Watts; Deirdre A. Byrne

2009-12-01T23:59:59.000Z

52

CDIAC Climate Data: Available Variables  

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

Climate Variables Available in CDIAC Data Products Temperature Precipitation Cloudiness Sunshine Duration Snowfall and Snow Depth Atmospheric Pressure Atmospheric Moisture Surface...

53

Development of a cavitating descaling technique for on-line geothermal pipe and component cleaning and scale removal. Final report  

DOE Green Energy (OSTI)

The use of cavitation for cleaning and removing geothermal scale from pipes and system components is discussed. A study of the technical feasibility of using cavitation to remove scale is described including the preliminary fold test, the GLEF in-plant field demonstration, a production line cleaning trial, and recommendations. (MHR)

Howard, S.C.; Bohli, W.H.

1980-01-01T23:59:59.000Z

54

Deaerator pressure control system for a combined cycle steam generator power plant  

Science Conference Proceedings (OSTI)

In a combined cycle steam generation power plant, until steam extraction can be used to reheat the deaerator, the economizer and/or the pegging recirculation are controlled so as to track the pressure upwards of the autocirculation reheater from the low pressure evaporator with a certain lag in pressure, and to establish pressure in the deaerator on the decreasing trend of the autocirculation reheater at a slower rate and without lowering below a minimum pressure so as to prevent the occurrence of bubbling and cavitation effect.

Martens, A.; Myers, G. A.

1985-12-03T23:59:59.000Z

55

Initial observations of cavitation-induced erosion of liquid metal spallation target vessels at the Spallation Neutron Source  

Science Conference Proceedings (OSTI)

During operation of the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory the mechanical properties of the AISI 316L target module are altered by high-energy neutron and proton radiation. The interior surfaces of the target vessel are also damaged by cavitation-induced erosion, which results from repetitive rapid heating of the liquid mercury by high-energy proton beam pulses. Until recently no observations of cavitation-induced erosion were possible for conditions prototypical to the SNS. Post irradiation examination (PIE) of the first and second operational SNS targets was performed to gain insight into the radiation-induced changes in mechanical properties of the 316L target material and the extent of cavitation-induced erosion to the target vessel inner surfaces. Observations of cavitation-induced erosion of the first and second operational SNS target modules are presented here, including images of the target vessel interiors and specimens removed from the target beam-entrance regions.

McClintock, David A [ORNL; Riemer, Bernie [ORNL; Ferguson, Phillip D [ORNL; Carroll, Adam J [ORNL; Dayton, Michael J [ORNL

2012-01-01T23:59:59.000Z

56

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

Science Conference Proceedings (OSTI)

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.

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

2010-11-01T23:59:59.000Z

57

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

Science Conference Proceedings (OSTI)

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.

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

2006-08-01T23:59:59.000Z

58

Cavitation-erosion resistance of 316LN stainless steel in mercury containing metallic solutes  

Science Conference Proceedings (OSTI)

Room temperature cavitation tests of vacuum annealed type 316LN stainless steel were performed in pure mercury and in mercury 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 mercury. Qualitatively, each solute appeared to increase the tenacity of the post-test wetting of the Hg solutions and render the Hg mixture susceptible to manipulation of droplet shape. Published by Elsevier B.V.

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

2003-01-01T23:59:59.000Z

59

Assessment of Cavitation-Erosion Resistance of 316LN Stainless Steel Following a Nitro-Carburizing Surface Treatment  

SciTech Connect

A nitro-carburizing surface treatment known domestically as the Melonite process was applied to type 316LN stainless steel test pieces and exposed to sonication conditions in mercury using a vibratory horn technique. Cavitation-erosion damage was evaluated for extended exposures and compared to other surface treatments on the same substrate alloy. The results indicate that the Melonite process substantially retards weight loss and crater development for extended periods, but gradually is eroded/destroyed leading to exposure of the substrate and cavitation-erosion behavior similar to untreated specimens. Compared with other surface treatments, cavitation-erosion results indicate that specimens treated with Melonite perform similarly to specimens treated with a simple nitriding process. Neither the simple nitriding nor the Melonite treatment is quite as effective as a previously evaluated low temperature carburizing treatment, the latter being about a factor of three better than Melonite in terms of weight loss during sonication in mercury.

Pawel, Steven J [ORNL

2009-11-01T23:59:59.000Z

60

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

DOE Green Energy (OSTI)

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.

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

1981-08-01T23:59:59.000Z

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


61

Variable Screw Compressor, Variable Screw Compressor Suppliers ...  

U.S. Energy Information Administration (EIA)

Variable Screw Compressor Suppliers & air compressor Manufacturers Directory. Source Top Quality Variable Screw Compressor Suppliers, air ...

62

Recommendations for Controlling Cavitation, Flashing, Liquid Droplet Impingement, and Solid Particle Erosion in Nuclear Power Plant Piping Systems  

Science Conference Proceedings (OSTI)

This report describes the most common forms of erosion encountered in nuclear power plant piping systems—cavitation, flashing, liquid droplet impingement, and solid particle erosion—and provides utility engineers with information on how to deal with these forms of damage.

2004-11-15T23:59:59.000Z

63

Performance Variability  

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

Variability Variability of Highly Parallel Architectures William T.C. Kramer 1 and Clint Ryan 2 1 Department of Computing Sciences, University of California at Berkeley and the National Energy Research Scientific Computing Center, Lawrence Berkeley National Laboratory 2 Department of Computing Sciences, University of California at Berkeley Abstract. The design and evaluation of high performance computers has concentrated on increasing computational speed for applications. This performance is often measured on a well configured dedicated sys- tem to show the best case. In the real environment, resources are not always dedicated to a single task, and systems run tasks that may influ- ence each other, so run times vary, sometimes to an unreasonably large extent. This paper explores the amount of variation seen across four large distributed memory systems in a systematic manner. It then

64

Pressure Tubes  

Science Conference Proceedings (OSTI)

Table 8   Specifications for carbon and alloy steel pressure tubes (ASTM)...medium-strength carbon-molybdenum alloy

65

Dynamic Pressure  

Science Conference Proceedings (OSTI)

... The higher pressure range will cover the important application of gas turbine engine testing. Gas turbines are used for propulsion on aircraft and ...

2013-07-15T23:59:59.000Z

66

CAVITATION DAMAGE MEASUREMENTS IN MERCURY BY RADIOTRACER ANALYSIS. Technical Report No. 10  

SciTech Connect

The development of a method of continuous measurement of the wear of metal specimens submitted to a constant cavitation field by using radiotracer techniques was attempted. Samples of type 302 stainless steel and type 1010 carbon steel were irradiated in a nuclear reactor and then placed in a cavitating venturi in a closed-loop mercury facility. It was discovered that due to the arrangement of the centrifugal pump, the radioactive particles of steel separate at once and tend to be trapped on the liquid surface of the pump sump. By dismantling this sump, about 6% of the measured weight loss of the carbon steel specimens was recovered. This radioactive material was collected and filtered, which allowed a classification by size with the following results: 68.95% of the material was retained on a 53 micron filter, 30.75% was retained on a 10 micron filter, and 0.307% was retained on a 2 micron filter. These results were obtained by comparison of the activity of the debris with the activity of a standard sample prepared from the original irradiated specimen. Differential curves obtained for the different size debris indicate that the constituents do not vary with particle size. On the assumption that the particles are spheres, it was found that the size distribution of the debris recovered was as follows: 6000 particles with a diameter of 53 microns, 14,750 with an average diameter of 30 microns, and 18,400 with an average diameter of 6 microns. Very few particles exceed a diameter of 80 microns (3.15 mils) and very few have a dimension of less than 6 microns (.236 mils). (auth)

Smith, W.; Nieto, J.M.; Hammitt, F.G.

1963-10-01T23:59:59.000Z

67

Orthobaric Density: A Thermodynamic Variable for Ocean Circulation Studies  

Science Conference Proceedings (OSTI)

A new density variable, empirically corrected for pressure, is constructed. This is done by first fitting compressibility (or sound speed) computed from global ocean datasets to an empirical function of pressure and in situ density (or specific ...

Roland A. de Szoeke; Scott R. Springer; David M. Oxilia

2000-11-01T23:59:59.000Z

68

Comparison of Cavitation-Erosion Resistance of Carburized and Carburized-Plus-Nitrided 316LN Stainless Steel in Mercury  

SciTech Connect

Annealed type 316LN stainless steel in the (1) carburized and the (2) carburized plus nitrided conditions was evaluated for cavitation-erosion resistance in ambient temperature mercury using a vibratory horn method. The results indicated that, relative to the specimens receiving only the carburizing treatment, the specimens that received both surface treatments exhibited substantially greater weight loss, general thinning, and profile development as a function of sonication time - with all observed degradation limited to the nitrided layer. Further, the nitride layer was observed to be susceptible to extensive cracking (occasionally leading to spallation), but the cracking was never observed to penetrate into the carburized layer. These screening test results suggest there is no improvement in cavitation-erosion resistance associated with augmentation of the carburizing treatment with plasma nitriding.

Pawel, Steven J [ORNL

2007-05-01T23:59:59.000Z

69

Assessment of Cavitation-Erosion Resistance of Potential Pump Impeller Materials for Mercury Service at the Spallation Neutron Source  

SciTech Connect

Using a standard vibratory horn apparatus, the relative cavitation-erosion resistance of a number of cast alloys in mercury was evaluated to facilitate material selection decisions for Hg pumps. The performance of nine different alloys - in the as-cast condition as well as following a case-hardening treatment intended to increase surface hardness - was compared in terms of weight loss and surface profile development as a function of sonication time in Hg at ambient temperature. The results indicated that among several potentially suitable alloys, CD3MWCuN perhaps exhibited the best overall resistance to cavitation in both the as-cast and surface treated conditions while the cast irons examined were found unsuitable for service of this type. However, other factors, including cost, availability, and vendor schedules may influence a material selection among the suitable alloys for Hg pumps.

Pawel, Steven J [ORNL

2007-03-01T23:59:59.000Z

70

Pulsed laser ablation plasmas generated in CO{sub 2} under high-pressure conditions up to supercritical fluid  

Science Conference Proceedings (OSTI)

Pulsed laser ablation of solids in supercritical media has a large potential for nanomaterials fabrication. We investigated plasmas generated by pulsed laser ablation of Ni targets in CO{sub 2} at pressures ranging from 0.1 to 16 MPa at 304.5 K. Plasma species were characterized by optical emission spectroscopy, and the evolution of cavitation bubbles and shockwaves were observed by time-resolved shadowgraph imaging. Ni and O atomic emissions decreased with increasing gas pressure; however, near the critical point the intensities reached local maxima, probably due to the enhancement of the plasma excitation and effective quenching resulting from the large density fluctuation.

Kato, Toru; Stauss, Sven; Kato, Satoshi; Urabe, Keiichiro; Terashima, Kazuo [Department of Advanced Materials Science, Graduate School of Frontier Sciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan); Baba, Motoyoshi; Suemoto, Tohru [Division of Advanced Spectroscopy, Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan)

2012-11-26T23:59:59.000Z

71

Analytical and experimental study of the acoustics and the flow field characteristics of cavitating self-resonating water jets  

DOE Green Energy (OSTI)

Waterjet nozzles (STRATOJETS) have been developed which achieve passive structuring of cavitating submerged jets into discrete ring vortices, and which possess cavitation incipient numbers six times higher than obtained with conventional cavitating jet nozzles. In this study we developed analytical and numerical techniques and conducted experimental work to gain an understanding of the basic phenomena involved. The achievements are: (1) a thorough analysis of the acoustic dynamics of the feed pipe to the nozzle; (2) a theory for bubble ring growth and collapse; (3) a numerical model for jet simulation; (4) an experimental observation and analysis of candidate second-generation low-sigma STRATOJETS. From this study we can conclude that intensification of bubble ring collapse and design of highly resonant feed tubes can lead to improved drilling rates. The models here described are excellent tools to analyze the various parameters needed for STRATOJET optimizations. Further analysis is needed to introduce such important factors as viscosity, nozzle-jet interaction, and ring-target interaction, and to develop the jet simulation model to describe the important fine details of the flow field at the nozzle exit.

Chahine, G.L.; Genoux, P.F.; Johnson, V.E. Jr.; Frederick, G.S.

1984-09-01T23:59:59.000Z

72

PRESSURE TRANSDUCER  

DOE Patents (OSTI)

A pressure or mechanical force transducer particularly adaptable to miniature telemetering systems is described. Basically the device consists of a transistor located within a magnetic field adapted to change in response to mechanical force. The conduction characteristics of the transistor in turn vary proportionally with changes in the magnetic flux across the transistor such that the output (either frequency of amplitude) of the transistor circuit is proportional to mechanical force or pressure.

Sander, H.H.

1959-10-01T23:59:59.000Z

73

Numerical Simulation of Squeeze Film Dampers and Study of the Effect of Central Groove on the Dynamic Pressure Distribution  

E-Print Network (OSTI)

Squeeze film dampers are used in the high speed turbo machinery industry and aerospace industries as a means to reduce vibration amplitude, to provide damping, to improve dynamic stability of the rotor bearing system and to isolate structural components. The effects of cavitation included in previous studies were not effective. The effect of different design parameters were not studied thoroughly as experimental investigation of squeeze film dampers is very expensive. Few of them used numerical investigation but the methods they used are either time consuming or complicated. The present study investigated the feasibility of applying a steady state solver, which is computationally less expensive, for analyzing flow field inside the squeeze film dampers. The behavior of dynamic pressure profiles at different operating conditions, and the effect of a central groove on dynamic pressure profiles were also studied. Simulation results of a 3D case which is similar to the one experimentally studied by Delgado were used to establish if the moving reference frame (MRF) model in Fluent 12.1 can be used. A steady state solver in an absolute frame of reference was used to produce whirling motion of the rotor in this study. The inlet pressure of 31kpa and the whirling speed of 50 and 100Hz were used as boundary conditions. The mixture model with three percent dissolved air in lubricant is used to model multiphase flow. Singhal cavitation model is used to model cavitation. The simulations (50,000 iterations) were run until steady state solutions were reached. The results closely agreed with those obtained experimentally by San Andrés and Delgado. Numerical simulations of three-dimensional cases with an additional central groove on the squeeze film land were also performed to predict the effect of central groove on dynamic pressure profiles. Addition central groove reduces the pressures and forces generated by squeeze film damper.

Boppa, Praneetha

2011-08-01T23:59:59.000Z

74

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

Science Conference Proceedings (OSTI)

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.

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

2010-01-01T23:59:59.000Z

75

Absolute permeability as a function of confining pressure, pore pressure and temperature  

SciTech Connect

This work is an investigation of the absolute permeability of unconsolidated sand and consolidated sandstone cores to distilled water as a function of the temperature of the system, confining pressure on the core and the pore pressure of the flowing liquid. The results of this study indicate that temperatures is not an important variable that needs to be reproduced in the laboratory. Confining pressure and pore pressure affect permeability in a predictable manner. This allows measurements at a lower pressure level to be extrapolated to higher pressure conditions. 21 refs.

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

1981-01-01T23:59:59.000Z

76

Energy Savings of Variable Speed Motors  

E-Print Network (OSTI)

This paper investigates the energy savings available by utilizing variable speed motors on pump and fan applications. Conventional control of flow or pressure in process plants is normally accomplished by throttling the various streams with control valves. Depending on the system and the actual operating conditions, this throttling may consume a considerable amount of energy. The hydraulics of different systems are investigated to generalize high energy saving applications. Typical pump characteristics at varying speeds are investigated since most performance curves are only available at a constant speed. The various types of variable speed electric motors are discussed. However, the primary variable speed system recommended is a variable frequency speed system which utilizes standard induction motors. Specific cases of centrifugal pump applications and cooling tower fan service are presented. Turndown frequencies, stream factors, and electric rates are included in the evaluation. The energy savings of a variable speed system becomes significant when flow rates vary widely and the electrical rates are high.

Fishel, F. D.

1979-01-01T23:59:59.000Z

77

A strain gage?variable area flowmeter  

Science Conference Proceedings (OSTI)

This article presents a unique hybrid flowmeter that combines the turndown ratio/low resistance benefits of a variable area differential pressure flowmeter with the low component simplicity of a target flowmeter. The design attaches a single element strain gage to the flexural membrane suspended in a fluid flow passage

D. W. Guillaume; D. DeVries

1990-01-01T23:59:59.000Z

78

Short-Term Climatic Variability of the Arctic  

Science Conference Proceedings (OSTI)

The circulation of the Arctic atmosphere undergoes large fluctuations about its monthly and annual means. The statistics of Arctic sea level pressure and temperature are evaluated in order to place Arctic atmospheric variability into the context ...

John E. Walsh; William L. Chapman

1990-02-01T23:59:59.000Z

79

Using Passive Cavitation Detection to Observe Postexcitation Response of Ultrasound Contrast  

E-Print Network (OSTI)

Research Laboratory, Department of Electrical and Computer Engineering, University of Illinois at Urbana to exhibit greater postexcitation at lower acoustic pressure thresholds than albumin-shelled microbubbles in diameter from 1-10 µm. Current clinical usage of UCAs consists primarily of diagnostic imaging, but much

Illinois at Urbana-Champaign, University of

80

pressure_measurements  

Science Conference Proceedings (OSTI)

... piston gauges, ball gages, pressure transducers, pressure gauges, non-mercurial barometers, and manometers in both gas and oil media using ...

2013-06-30T23:59:59.000Z

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


81

Gas pressure reduction circuits  

Science Conference Proceedings (OSTI)

This note describes passive pressure reduction devices for use with sensitive instruments. Two gas circuits are developed which not only provide a pressure reduction under flow demand

D. W. Guillaume; D. DeVries

1989-01-01T23:59:59.000Z

82

Assessment of End-of-Life Behavior of the Surface Modification to Improve Cavitation-Erosion Resistance in the Mercury Target at the Spallation Neutron Source  

SciTech Connect

The cavitation-erosion resistance of the Kolsterised{reg_sign} layer on annealed or cold-worked substrates of 316LN stainless steel has been examined in mercury using a vibratory horn technique and extended exposure periods intended to expose 'end-of-life' performance characteristics. The Kolsterised{reg_sign} layer tends to remain protective--as evidenced by modest steady-state weight loss and surface roughness increases, only isolated pitting, and limited wetting by mercury--until the protective layer has been thinned by general erosion to about 15-20 {micro}m. Prior to that amount of erosion, the cavitation-erosion resistance of both types of specimens appears defined by the properties of the protective layer. However, after thinning to such a degree, initial breakdown of the protective layer is characterized by increases in both the surface roughness and the number/depth of individual pits across the surface at a rate that is strongly dependent on the substrate condition, with annealed substrates significantly more prone to damage. However, even as the protective properties of the Kolsterised{reg_sign} layer decrease, both weight change and profile development as a function of sonication time suggest a gradual reversion to cavitation-erosion behavior similar to that of untreated substrates.

Pawel, Steven J [ORNL

2007-06-01T23:59:59.000Z

83

Effect of Process Variables  

Science Conference Proceedings (OSTI)

Pressure Water Leaching Molybdenum and Nickel from Mo-Ni Ore of Black Shale without Reagent · Recovery of Rare Earth Metals from Wasted Magnet.

84

VARIABLE TIME DELAY MEANS  

DOE Patents (OSTI)

An electrically variable time delay line is described which may be readily controlled simuitaneously with variable impedance matching means coupied thereto such that reflections are prevented. Broadly, the delay line includes a signal winding about a magnetic core whose permeability is electrically variable. Inasmuch as the inductance of the line varies directly with the permeability, the time delay and characteristic impedance of the line both vary as the square root of the permeability. Consequently, impedance matching means may be varied similariy and simultaneously w:th the electrically variable permeability to match the line impedance over the entire range of time delay whereby reflections are prevented.

Clemensen, R.E.

1959-11-01T23:59:59.000Z

85

PressurePressure Indiana Coal Characteristics  

E-Print Network (OSTI)

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

Fernández-Juricic, Esteban

86

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

E-Print Network (OSTI)

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.

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

2013-01-01T23:59:59.000Z

87

Estimated Global Hydrographic Variability  

Science Conference Proceedings (OSTI)

An estimate is made of the three-dimensional global oceanic temperature and salinity variability, omitting the seasonal cycle, both as a major descriptive element of the ocean circulation and for use in the error estimates of state estimation. ...

Gaël Forget; Carl Wunsch

2007-08-01T23:59:59.000Z

88

Understanding Biomass Feedstock Variability  

SciTech Connect

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.

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

2013-01-01T23:59:59.000Z

89

PRESSURE WELDING--BIBLIOGRAPHY  

SciTech Connect

A bibliography containing 117 references from the years 1944 to 1961 on pressure welding is presented. (N.W.R.)

1960-01-01T23:59:59.000Z

90

Property:Special Physical Features | Open Energy Information  

Open Energy Info (EERE)

Physical Features Physical Features Jump to: navigation, search Property Name Special Physical Features Property Type Text Pages using the property "Special Physical Features" Showing 25 pages using this property. (previous 25) (next 25) C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + The 2-Foot Variable Pressure Cavitation Water Tunnel is a vertical plane, closed recirculating, variable-speed, variable-pressure, open jet test section, closed jet test section, and semi-rectangular test section. Carderock 3-ft Variable Pressure Cavitation Water Tunnel + The 3-ft Variable Pressure Cavitation Water Tunnel is a vertical plane, closed recirculating with resorber, variable-speed, variable-pressure, two interchangeable circular test sections. Carderock Circulating Water Channel + The Circulating Water Channel is a vertical plane, open to the atmosphere test section with a free surface in a closed recirculating water circuit, variable speed, rectangular cross-sectional shape facility. There are 10 large viewing windows on either side of the test section at different elevations and 9 in the bottom; movable bridge spans the test section for ease and versatility in mounting models, rigging bridge is capable of taking towing loads at any one of numerous points up to 35,584 N

91

Property:Velocity(m/s) | Open Energy Information  

Open Energy Info (EERE)

Velocity(m/s) Velocity(m/s) Jump to: navigation, search Property Name Velocity(m/s) Property Type String Pages using the property "Velocity(m/s)" Showing 21 pages using this property. A Alden Small Flume + >0.9 + B Bucknell Hydraulic Flume + 2.7 + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + 17 + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + 25.8 + Carderock Circulating Water Channel + 5.2 + Carderock Large Cavitation Tunnel + 18 + Carderock Subsonic Wind Tunnel + 83.8 + D DeFrees Flume 1 + 2 + DeFrees Flume 2 + 2 + DeFrees Flume 3 + 2 + DeFrees Flume 4 + 2 + M MHL Free Surface Channel + 2 + MHL High Speed Cavitation + 25.9 + MHL Student Tunnel + 4.6 + P Penn Large Water Tunnel + 16.8 + Penn Small Water Tunnel + 21 + S SAFL Channel + 6.1 +

92

Pressure reducing regulator  

DOE Patents (OSTI)

A pressure reducing regulator that controls its downstream or outlet pressure to a fixed fraction of its upstream or inlet pressure is disclosed. The regulator includes a housing which may be of a titanium alloy, within which is located a seal or gasket at the outlet end which may be made of annealed copper, a rod, and piston, each of which may be made of high density graphite. The regulator is insensitive to temperature by virtue of being without a spring or gas sealed behind a diaphragm, and provides a reference for a system in which it is being used. The rod and piston of the regulator are constructed, for example, to have a 1/20 ratio such that when the downstream pressure is less than 1/20 of the upstream pressure the regulator opens and when the downstream pressure exceeds 1/20 of the upstream pressure the regulator closes. 10 figs.

Whitehead, J.C.; Dilgard, L.W.

1995-10-10T23:59:59.000Z

93

Variable Speed Drive Volumetric Tracking (VSDVT) for Airflow Control in Variable Air Volume (VAV) Systems  

E-Print Network (OSTI)

An airflow control method has been developed for variable air volume (VAV) systems. This airflow control method is named VSD volumetric tracking (VSDVT) since both the supply and return airflows are determined using signals of the variable speed drives (VSD) instead of the flow stations. Its performance is studied and compared with the fan tracking (FT) method using model simulations. The VSDVT maintains a constant building pressure and the required outside airflow under all load conditions, reduces the annual return air fan energy by up to 50%, and the annual supply air fan energy by up to 30%. This paper presents the VSDVT method, the system models, and the simulation results.

Liu, M.

2002-01-01T23:59:59.000Z

94

Georeactor Variability and Integrity  

E-Print Network (OSTI)

As a deep-Earth energy source, the planetocentric nuclear-fission georeactor concept is on a more secure scientific footing than the previous idea related to the assumed growth of the inner core. Unlike previously considered deep-Earth energy sources, which are essentially constant on a human time-scale, variability in nuclear fission reactors can arise from changes in composition and/or position of fuel, moderators, and neutron absorbers. Tantalizing circumstantial evidence invites inquiry into the possibility of short-term planetocentric nuclear fission reactor variability. This brief communication emphasizes the importance of scientific integrity and highlights the possibility of variable georeactor power output so that these might be borne in mind in future investigations, especially those related to the Earth's heat flux.

J. Marvin Herndon

2005-10-04T23:59:59.000Z

95

Georeactor Variability and Integrity  

E-Print Network (OSTI)

As a deep-Earth energy source, the planetocentric nuclear-fission georeactor concept is on a more secure scientific footing than the previous idea related to the assumed growth of the inner core. Unlike previously considered deep-Earth energy sources, which are essentially constant on a human time-scale, variability in nuclear fission reactors can arise from changes in composition and/or position of fuel, moderators, and neutron absorbers. Tantalizing circumstantial evidence invites inquiry into the possibility of short-term planetocentric nuclear fission reactor variability. This brief communication emphasizes the importance of scientific integrity and highlights the possibility of variable georeactor power output so that these might be borne in mind in future investigations, especially those related to the Earth's heat flux.

Herndon, J M

2005-01-01T23:59:59.000Z

96

Modeling 18° Water Variability  

Science Conference Proceedings (OSTI)

Variability of 18° Water formation is investigated with an isopycnic-coordinate model of the North Atlantic. A 30-year spinup integration is used as a “control” experiment in which the upper water column in the Sargasso Sea is shown to be in ...

Robert Marsh; Adrian L. New

1996-06-01T23:59:59.000Z

97

Pressurized fluidized bed reactor  

DOE Patents (OSTI)

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.

Isaksson, Juhani (Karhula, FI)

1996-01-01T23:59:59.000Z

98

Pressurized fluidized bed reactor  

DOE Patents (OSTI)

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.

Isaksson, J.

1996-03-19T23:59:59.000Z

99

CC Pressure Test  

SciTech Connect

The inner vessel heads including bypass and beam tubes had just been welded into place and dye penetrant checked. The vacuum heads were not on at this time but the vacuum shell was on covering the piping penetrating into the inner vessel. Signal boxes with all feed through boards, the instrumentation box, and high voltage boxes were all installed with their pump outs capped. All 1/4-inch instrumentation lines were terminated at their respective shutoff valves. All vacuum piping used for pumping down the inner vessel was isolated using o-ring sealed blind flanges. PV215A (VAT Series 12), the 4-inch VRC gate valve isolating the cyropump, and the rupture disk had to be removed and replaced with blind flanges before pressurizing due to their pressure limitations. Stresses in plates used as blind flanges were checked using Code calcualtions. Before the CC test, vacuum style blanks and clamps were hydrostatically pressure tested to 150% of the maximum test pressure, 60 psig. The Code inspector and Research Division Safety had all given their approval to the test pressure and procedure prior to filling the vessel with argon. The test was a major success. Based on the lack of any distinguishable pressure drop indicated on the pressure gages, the vessel appeared to be structurally sound throughout the duration of the test (approx. 3 hrs.). A major leak in the instrumentation tubing was discovered at half of the maximum test pressure and was quickly isolated by crimping and capping with a compression fitting. There were some slight deviations in the actual procedure used. The 44 psig relief valve located just outside the cleanroom had to be capped until the pressure in the vessel indicated 38 psi. This was to allow higher supply pressures and hence, higher flows through the pressurizing line. Also, in order to get pressure readings at the cryostat without exposing any personnel to the potentially dangerous stored energy near the maximum test pressure, a camera was installed at the top of the vessel to view the indicator mounted there. The monitor was viewed at the ante room adjacent to the cleanroom. The holding pressure of 32 psig (4/5 of the maximum test pressure) was only maintained for about 20 minutes instead of the half hour recommendation in the procedure. We felt that this was sufficient time to Snoop test and perform the pressure drop test. After the test was completed, the inspector for CBI Na-Con and the Research Divison Safety Officer signed all of required documentation.

Dixon, K.; /Fermilab

1990-07-12T23:59:59.000Z

100

Hydrostatic Pressure Retainment.  

E-Print Network (OSTI)

??There is a great deal of attention being concentrated on reducing the weight of pressure vessels and fuel/oxidizer tanks (tankage) by 10% to 20%. Most… (more)

Setlock, Robert J., Jr.

2004-01-01T23:59:59.000Z

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


101

Miniaturized pressurization system  

DOE Patents (OSTI)

This invention relates to pressurization systems and liquid rocket propulsion systems, and particularly to those used to attitude control or maneuvering of small space vehicles or airborne vehicles where the requirement for thrust is intermittent rather than continuous, and must be available rapidly upon demand. This invention also relates to increasing performance of such propulsion systems, by way of eliminating inert mass from the propulsion system. The invention uses a fluid stored at a low pressure and provides the fluid at a high pressure. The invention allows the low pressure fluid to flow to a fluid bore of a differential pump and from the pump to a fluid pressure regulator. After flowing through the regulator the fluid is converted to a gas which is directed to a gas bore of the differential pump. By controlling the flow of gas entering and being exhausted from the gas bore, the invention provides pressure to the fluid. By setting the regulator, the high pressure fluid can be set at predetermined values. Because the invention only needs a low pressure fluid, the inventive apparatus has a low mass, and therefore would be useful in rocket propulsion systems.

Whitehead, J.C.; Swink, D.G.

1990-12-31T23:59:59.000Z

102

Hot-electron generation by 'cavitating' Langmuir turbulence in the nonlinear stage of the two-plasmon-decay instability  

SciTech Connect

The kinetic reduced-description particle-in-cell simulation technique has been applied to study the nonlinear stage of two-plasmon-decay (TPD) instability in an inhomogeneous plasma driven by crossed laser beams. The TPD instability is found to be a prolific generator of 'cavitating' Langmuir turbulence. Langmuir 'cavitons'-localized longitudinal electric fields, oscillating near the local electron plasma frequency, trapped in ponderomotive density depressions-collapse to dimensions of a few electron Debye lengths, where the electric field energy is collisionlessly transferred to electron kinetic energy. The resulting hot electrons can attain instantaneous temperatures up to 100 keV with net suprathermal heat flux out of the system of up to a few percent of the input laser energy. Scaling laws for this hot-electron generation by TPD, in regimes motivated by recent experiments on the Omega laser, were presented recently by Vu et al. (H. X. Vu, D. F. DuBois, D. A. Russell, and J. F. Myatt, Phys. Plasmas 19, 102703 (2012)). This paper concentrates on the microscopic mechanisms for hot-electron generation. The spatial distribution of the maxima of the electric field envelope modulus is found to be very spiky, with the distribution of electric field envelope maxima obeying Gaussian statistics. The cavitons are produced in density-depletion trenches produced by the combined ponderomotive interference of the crossed laser beams and the ponderomotive beats of the primary backward-going TPD Langmuir waves (LWs) resulting from the crossed beams. The Langmuir turbulence is strongest in the electron-density region near 0.241 Multiplication-Sign the laser's critical density, where the forward LWs from the crossed-beam TPD are degenerate. Nucleation of cavitons is assisted by the modulation of the electron density in the trenches, which in turn is caused by the beating of the common forward-going LW and the pair of backward-going LWs. The autocorrelation function of the LW envelope field provides a near-universal shape for intense cavitons-in the neighborhood of the local field maxima. The hot-electron temperature is found to be approximately a linear function of the 'caviton temperature' determined from the Gaussian distribution of caviton maxima. These diagnostics provide strong evidence for the importance of Langmuir caviton collapse in the generation of hot electrons by TPD. Extended Zakharov model predictions for TPD exhibit the same qualitative phenomena.

Vu, H. X. [Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093 (United States); DuBois, D. F. [Lodestar Research Corporation, Boulder, Colorado 80301 (United States); Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Russell, D. A. [Lodestar Research Corporation, Boulder, Colorado 80301 (United States); Myatt, J. F. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)

2012-10-15T23:59:59.000Z

103

PRESSURE ACTIVATED SEALANT TECHNOLOGY  

Science Conference Proceedings (OSTI)

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.

Michael A. Romano

2004-04-01T23:59:59.000Z

104

Variable percentage sampler  

DOE Patents (OSTI)

A remotely operable sampler is provided for obtaining variable percentage samples of nuclear fuel particles and the like for analyses. The sampler has a rotating cup for a sample collection chamber designed so that the effective size of the sample inlet opening to the cup varies with rotational speed. Samples of a desired size are withdrawn from a flowing stream of particles without a deterrent to the flow of remaining particles.

Miller, Jr., William H. (Knoxville, TN)

1976-01-01T23:59:59.000Z

105

Variable laser attenuator  

DOE Patents (OSTI)

The disclosure relates to low loss, high power variable attenuators comprising one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength. 9 figs.

Foltyn, S.R.

1987-05-29T23:59:59.000Z

106

Variable laser attenuator  

SciTech Connect

The disclosure relates to low loss, high power variable attenuators comprng one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength.

Foltyn, Stephen R. (Los Alamos, NM)

1988-01-01T23:59:59.000Z

107

Solar-type Variables  

E-Print Network (OSTI)

The rich acoustic oscillation spectrum in solar-type variables make these stars particularly interesting for studying fluid-dynamical aspects of the stellar interior. I present a summary of the properties of solar-like oscillations, how they are excited and damped and discuss some of the recent progress in using asteroseismic diagnostic techniques for analysing low-degree acoustic modes. Also the effects of stellar-cycle variations in low-mass main-sequence stars are addressed.

Houdek, Gunter

2009-01-01T23:59:59.000Z

108

Errors in all variables  

SciTech Connect

We present a thorough derivation of the posterior for the straight line fit employing the hyper-plane prior. For the example of the parabola we enlarge the scope to nonlinear problems, however simplify it to be solved resembling the straight line solution. Finally we come to the problem of determining the exponents of a scaling law, where in logarithmic form the scaling exponents are linear coefficients of logarithmic variables.

Preuss, R.; Dose, V. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)

2005-11-23T23:59:59.000Z

109

Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture  

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

Hydrogen-Assisted Fracture: Materials Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture Brian Somerday, Chris San Marchi, and Dorian Balch Sandia National Laboratories Livermore, CA Hydrogen Pipeline Working Group Workshop Augusta, GA August 30-31, 2005 SNL has 40+ years experience with effects of high-pressure hydrogen gas on materials * Design and maintenance of welded stainless steel pressure vessels for containment of high-pressure H 2 isotopes - Extensive testing of stainless steels exposed to high-pressure H 2 gas * Six-year program in 1970s focused on feasibility of using natural gas pipeline network for H 2 gas - Materials testing in high-pressure H 2 gas using laboratory specimens and model pipeline - Examined fusion zone and heat affected zones of welds * Active SNL staff have authored 70+ papers and organized 6

110

Envera Variable Compression Ratio Engine  

DOE Green Energy (OSTI)

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

Charles Mendler

2011-03-15T23:59:59.000Z

111

Pressurizer tank upper support  

DOE Patents (OSTI)

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.

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

1994-01-11T23:59:59.000Z

112

Pressurizer tank upper support  

DOE Patents (OSTI)

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.

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

1994-01-01T23:59:59.000Z

113

Jets with Variable R  

E-Print Network (OSTI)

We introduce a new class of jet algorithms designed to return conical jets with a variable Delta R radius. A specific example, in which Delta R scales as 1/pT, proves particularly useful in capturing the kinematic features of a wide variety of hard scattering processes. We implement this Delta R scaling in a sequential recombination algorithm and test it by reconstructing resonance masses and kinematic endpoints. These test cases show 10-20% improvements in signal efficiency compared to fixed Delta R algorithms. We also comment on cuts useful in reducing continuum jet backgrounds.

David Krohn; Jesse Thaler; Lian-Tao Wang

2009-03-02T23:59:59.000Z

114

Decadal Variability of the Aleutian Low and Its Relation to High-Latitude Circulation  

Science Conference Proceedings (OSTI)

The January–February mean central pressure of the Aleutian low is investigated as an index of North Pacific variability on interannual to decadal timescales. Since the turn of the century, 37% of the winter interannual variance of the Aleutian ...

James E. Overland; Jennifer Miletta Adams; Nicholas A. Bond

1999-05-01T23:59:59.000Z

115

Interannual Variability of Surface Fields over the Indian Ocean during Recent Decades  

Science Conference Proceedings (OSTI)

The interannual variability of surface meteorological fields over the Indian Ocean during the period 1954–76 is studied using 2 million ship reports obtained from different sources. Monthly mean fields of wind, pressure, air temperature, mixing ...

Daniel L. Cadet; Bradley C. Diehl

1984-10-01T23:59:59.000Z

116

North Pacific Decadal Variability and Climate Change in the IPCC AR4 Models  

Science Conference Proceedings (OSTI)

The two leading modes of North Pacific sea surface temperature (SST) and sea level pressure (SLP), as well as their connections to tropical variability, are explored in the 24 coupled climate models used in the Intergovernmental Panel on Climate ...

Jason C. Furtado; Emanuele Di Lorenzo; Niklas Schneider; Nicholas A. Bond

2011-06-01T23:59:59.000Z

117

ARM - Measurement - Atmospheric pressure  

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

pressure pressure ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Atmospheric pressure The pressure exerted by the atmosphere as a consequence of gravitational attraction exerted upon the "column" of air lying directly above the point in question. Categories Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments SONDE : Balloon-Borne Sounding System CO2FLX : Carbon Dioxide Flux Measurement Systems ECOR : Eddy Correlation Flux Measurement System

118

Giraffe blood pressure  

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

thing that happens to you when you raise or lower your head. The arteries serving your heart (carotids) constrict when you lower your head, and that lowers the blood pressure...

119

Capacitance pressure sensor  

DOE Patents (OSTI)

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).

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

2000-01-01T23:59:59.000Z

120

Critical CRBR core pressure  

Science Conference Proceedings (OSTI)

The conditions are detailed under which gas pressure will cause or initiate failure in the structural containment of the fuel core. The Clinch River Breeder Reactor Plant is the prototype structure. Two general classes of problems have been studied, representing two entirely distinct configurations of containment failure. The first model determines the minimum pressure to lift a portion or the entire core from its containment. The second model estimates the critical pressure above which the fuel rods interior to the hexagonal fuel can warp, leading to blockage of the gas passages. Such blockage might cause further buildup of the gas pressure to a level causing the failure of the fuel rod containment in the hexagonal fuel container.

Ju, F.D.

1980-06-01T23:59:59.000Z

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


121

Pressure multiplying dispenser  

SciTech Connect

A pressure multiplying dispenser for delivering fluid, preferably as a spray to the atmosphere, from a source of fluid, preferably a spray bottle, is described. The dispenser includes in combination a hollow cylindrical member, a nozzle delivery tube within the cylindrical member and a hollow actuator piston slideable within the cylindrical member which acts to multiply the pressure of a squeeze applied to the spray bottle.

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

1986-01-01T23:59:59.000Z

122

Solar Irradiance Variability  

E-Print Network (OSTI)

The Sun has long been considered a constant star, to the extent that its total irradiance was termed the solar constant. It required radiometers in space to detect the small variations in solar irradiance on timescales of the solar rotation and the solar cycle. A part of the difficulty is that there are no other constant natural daytime sources to which the Sun's brightness can be compared. The discovery of solar irradiance variability rekindled a long-running discussion on how strongly the Sun affects our climate. A non-negligible influence is suggested by correlation studies between solar variability and climate indicators. The mechanism for solar irradiance variations that fits the observations best is that magnetic features at the solar surface, i.e. sunspots, faculae and the magnetic network, are responsible for almost all variations (although on short timescales convection and p-mode oscillations also contribute). In spite of significant progress important questions are still open. Thus there is a debat...

Solanki, Sami K

2012-01-01T23:59:59.000Z

123

ECN Pressure Test  

SciTech Connect

This note describes: the rationale for the test pressure of the inner ECN cryostat vessel, the equipment to be used in this test, the test procedure, the status of the vessel prior to the test, the actual test results, and a schematic diagram of the testing set up and the pressure testing permit. The test, performed in the evening of July 17, 1991, was a major success. Based on a neglible pressure drop indicated on the pressure gages (1/4 psi), the vessel appeared to be structurally sound throughout the duration of the test (approx. 1.5 hrs.). No pressure increases were observed on the indicators looking at the beam tube bellows volumes. There was no indication of bubbles form the soap test on the welds and most of the fittings that were checked. There were some slight deviations in the actual procedure used. The UO filter was removed after the vessel had bled down to about 18 psig in order to speed up that aspect of the test. The rationale was that the higher velocity gas had already passed through at the higher pressures and there was no visible traces of the black uo particles. The rate of 4 psi/10 minutes seemed incredibly slow and often that time was reduced to just over half that rate. The testing personnel was allowed to stay in the pit throughout the duration of the test; this was a slight relaxation of the rules.

Dixon, K.; /Fermilab

1991-07-18T23:59:59.000Z

124

Climate Variability, Fish, and Fisheries  

Science Conference Proceedings (OSTI)

Fish population variability and fisheries activities are closely linked to weather and climate dynamics. While weather at sea directly affects fishing, environmental variability determines the distribution, migration, and abundance of fish. ...

P. Lehodey; J. Alheit; M. Barange; T. Baumgartner; G. Beaugrand; K. Drinkwater; J.-M. Fromentin; S. R. Hare; G. Ottersen; R. I. Perry; C. Roy; C. D. van der Lingen; F. Werner

2006-10-01T23:59:59.000Z

125

Colorado River Basin Hydroclimatic Variability  

Science Conference Proceedings (OSTI)

An analysis of annual hydroclimatic variability in the Upper Colorado River basin (UCRB) for the period of 1906–2006 was performed to understand the dominant modes of multidecadal variability. First, wavelet-based spectral analysis was employed ...

Kenneth Nowak; Martin Hoerling; Balaji Rajagopalan; Edith Zagona

2012-06-01T23:59:59.000Z

126

Examination of Compatibility of Potentially Cavitation-Resistant Modifications of Type 316LN Stainless Steel with Mercury in a Thermal Convection Loop  

Science Conference Proceedings (OSTI)

A 316L stainless steel thermal convection loop (TCL) containing a variety of stainless steel coupons circulated mercury for 2000 h. The TCL conditions included a maximum temperature of 307 C, a maximum temperature gradient of 90 C, and a Hg velocity of about 1.4 m/min. In addition to mill-annealed/surface-ground 316LN coupons serving as the baseline material, other coupons included 316LN that was 50% cold-worked, 316LN that was given a proprietary surface hardening treatment termed ''kolsterizing,'' and Nitronic 60. The purpose of this test was to examine Hg compatibility with these modest variations of annealed 31 6LN stainless steel that are considered potential improvements over annealed 31 6LN for cavitation-erosion resistance in the Spallation Neutron Source (SNS) target containment system. The results indicated negligible weight change for each coupon type, no significant indication of attack or surface roughening, and generally no interaction with Hg.

Pawel, SJ

2002-08-29T23:59:59.000Z

127

Scalable analysis of variable software  

Science Conference Proceedings (OSTI)

The advent of variability management and generator technology enables users to derive individual variants from a variable code base based on a selection of desired configuration options. This approach gives rise to the generation of possibly billions ... Keywords: C Preprocessor, Liveness Analysis, Software Product Lines, Type Checking, Variability-aware Analysis

Jörg Liebig; Alexander von Rhein; Christian Kästner; Sven Apel; Jens Dörre; Christian Lengauer

2013-08-01T23:59:59.000Z

128

Variability within Modeling Language Definitions  

Science Conference Proceedings (OSTI)

We present a taxonomy of the variability mechanisms offered by modeling languages. The definition of a formal language encompasses a syntax and a semantic domain as well as the mapping that relates them, thus language variabilities are classified according ... Keywords: Modeling languages, UML, formal semantics, variability

María Victoria Cengarle; Hans Grönniger; Bernhard Rumpe

2009-10-01T23:59:59.000Z

129

Symmetrization Of Binary Random Variables  

E-Print Network (OSTI)

A random variable Y is called an independent symmetrizer of a given random variable X if (a) it is independent of X and (b) the distribution of X Y is symmetric about 0. In cases where the distribution of X is symmetric about its mean, it is easy to see that the constant random variable Y is a minimum-variance independent symmetrizer. Taking

Abram Kagan; Colin Mallows; Larry Shepp; Robert J. Vanderbei; Yehuda Vardi

1999-01-01T23:59:59.000Z

130

New Way To Realize Pressure  

Science Conference Proceedings (OSTI)

... Ever since then, civilization has used the toxic liquid metal to measure pressure. ... The pressure and temperature of a gas are directly related to its ...

2013-01-03T23:59:59.000Z

131

Passive blast pressure sensor  

DOE Patents (OSTI)

A passive blast pressure sensor for detecting blast overpressures of at least a predetermined minimum threshold pressure. The blast pressure sensor includes a piston-cylinder arrangement with one end of the piston having a detection surface exposed to a blast event monitored medium through one end of the cylinder and the other end of the piston having a striker surface positioned to impact a contact stress sensitive film that is positioned against a strike surface of a rigid body, such as a backing plate. The contact stress sensitive film is of a type which changes color in response to at least a predetermined minimum contact stress which is defined as a product of the predetermined minimum threshold pressure and an amplification factor of the piston. In this manner, a color change in the film arising from impact of the piston accelerated by a blast event provides visual indication that a blast overpressure encountered from the blast event was not less than the predetermined minimum threshold pressure.

King, Michael J.; Sanchez, Roberto J.; Moss, William C.

2013-03-19T23:59:59.000Z

132

Hydro-Pac Inc., A High Pressure Company  

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

Hydro-Pac Hydro-Pac Inc. A High Pressure Company * Founded in 1972 * Manufacturer of Hydraulically Driven Intensifiers * High Pressure Hydrogen Compressors Hydrogen Compressor Cost Reduction Topics * Standardize Configuration and Fueling Strategy * Simple Designs and Proven Technologies * Identify Economical Hydrogen Compatible Materials * Specify Well Ventilated Sites with Remote Controls Standardize Configuration and Fueling Strategy * Limit the number of compressors and stages * Narrow the range of supply and discharge pressures * Select a flow and standardize Simple Designs and Proven Technologies * Variable speed drives * Double ended intensifiers * Water cooled cylinders * Flexible operational envelopes * Stop and start under load . Material Research / Installation Requirements

133

PRESSURE SENSING DEVICE  

DOE Patents (OSTI)

This device is primarily useful as a switch which is selectively operable to actuate in response to either absolute or differential predetermined pressures. The device generally comprises a pressure-tight housing divided by a movable impermeable diaphragm into two chambers, a reference pressure chamber and a bulb chamber containing the switching means and otherwise filled with an incompressible non-conducting fluid. The switch means comprises a normally collapsed bulb having an electrically conductive outer surface and a vent tube leading to the housing exterior. The normally collapsed bulb is disposed such that upon its inflation, respensive to air inflow from the vent, two contacts fixed within the bulb chamber are adapted to be electrically shorted by the conducting outer surface of the bulb.

Pope, K.E.

1959-12-15T23:59:59.000Z

134

Pressure suppression containment system  

DOE Patents (OSTI)

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.

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

1994-03-15T23:59:59.000Z

135

Pressure suppression containment system  

DOE Patents (OSTI)

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.

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

1994-03-15T23:59:59.000Z

136

Second law analysis for a variable viscosity plane Poiseuille flow with asymmetric convective cooling  

Science Conference Proceedings (OSTI)

A second-law analysis of a pressure-driven variable viscosity fluid flow through a channel with asymmetric convective cooling at the walls is investigated. Flow is assumed to be steady, laminar and fully-developed. The effect of heat generation due to ... Keywords: Asymmetric convective cooling, Entropy generation analysis, Poiseuille flow, Variable viscosity

O. D. Makinde; A. Aziz

2010-12-01T23:59:59.000Z

137

Einstein's Gravity Under Pressure  

E-Print Network (OSTI)

The mysterious `dark energy' needed to explain the current observations, poses a serious confrontation between fundamental physics and cosmology. The present crisis may be an outcome of the (so far untested) prediction of the general theory of relativity that the pressure of the matter source also gravitates. In this view, a theoretical analysis reveals some surprising inconsistencies and paradoxes faced by the energy-stress tensor (in the presence of pressure) which is used to model the matter content of the universe, including dark energy.

Ram Gopal Vishwakarma

2007-05-07T23:59:59.000Z

138

Wellbore pressure transducer  

DOE Patents (OSTI)

Subterranean earth formations containing energy values are subjected to hydraulic fracturing procedures to enhance the recovery of the energy values. These fractures are induced in the earth formation by pumping liquid into the wellbore penetrating the earth formation until the pressure of the liquid is sufficient to fracture the earth formation adjacent to the wellbore. The present invention is directed to a transducer which is positionable within the wellbore to generate a signal indicative of the fracture initiation useful for providing a timing signal to equipment for seismic mapping of the fracture as it occurs and for providing a measurement of the pressure at which the fracture is initiated.

Shuck, Lowell Z. (Morgantown, WV)

1979-01-01T23:59:59.000Z

139

SALTSTONE OSMOTIC PRESSURE  

Science Conference Proceedings (OSTI)

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

Nichols, R.

2013-09-23T23:59:59.000Z

140

SALTSTONE OSMOTIC PRESSURE  

SciTech Connect

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

Nichols, R.

2013-09-23T23:59:59.000Z

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


141

Reactor pressure vessel nozzle  

DOE Patents (OSTI)

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.

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

1994-10-04T23:59:59.000Z

142

Pressure swing adsorption process  

SciTech Connect

An adiabatic pressure swing adsorption process is described for the separation of gas mixtures by adsorbing at least one gas component in each of at least 8 phase staggered operated adsorbent beds, which can continue to be operated without any stoppage of installation even if one adsorbent bed is removed from operation due to a defective valve. 6 claims.

De Meyer, H.; Doclo, R.; Seynaeve, J.

1980-11-18T23:59:59.000Z

143

INSTRUMENT TRANSMITTERS FOR HIGH-PRESSURE, AQUEOUS, NUCLEAR REACTORS  

SciTech Connect

A review of the criteria involved in the selection of primary sensing elements for the measurement of process variables in high-pressure, aqueous, nuclear reactors is presented. Some acceptable types of sensing elements now in use at ORNL are described. (auth)

Moore, R.L.

1958-10-28T23:59:59.000Z

144

VARIABLE TIME-INTERVAL GENERATOR  

DOE Patents (OSTI)

This patent relates to a pulse generator and more particularly to a time interval generator wherein the time interval between pulses is precisely determined. The variable time generator comprises two oscillators with one having a variable frequency output and the other a fixed frequency output. A frequency divider is connected to the variable oscillator for dividing its frequency by a selected factor and a counter is used for counting the periods of the fixed oscillator occurring during a cycle of the divided frequency of the variable oscillator. This defines the period of the variable oscillator in terms of that of the fixed oscillator. A circuit is provided for selecting as a time interval a predetermined number of periods of the variable oscillator. The output of the generator consists of a first pulse produced by a trigger circuit at the start of the time interval and a second pulse marking the end of the time interval produced by the same trigger circuit.

Gross, J.E.

1959-10-31T23:59:59.000Z

145

Economics of Steam Pressure Reduction  

E-Print Network (OSTI)

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 will address the following. 1. Factors that determine the feasibility of reducing the plant steam operating pressure. 2. The operating advantages and disadvantages associated with the decreased steam pressure. 3. The economics of steam pressure reduction. Appropriate visual aids will be utilized as part of the discussion.

Sylva, D. M.

1985-05-01T23:59:59.000Z

146

Pressure suppression system  

DOE Patents (OSTI)

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.

Gluntz, Douglas M. (San Jose, CA)

1994-01-01T23:59:59.000Z

147

High pressure furnace  

DOE Patents (OSTI)

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.

Morris, Donald E. (Kensington, CA)

1993-01-01T23:59:59.000Z

148

High pressure oxygen furnace  

DOE Patents (OSTI)

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.

Morris, D.E.

1992-07-14T23:59:59.000Z

149

High pressure oxygen furnace  

DOE Patents (OSTI)

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.

Morris, Donald E. (Kensington, CA)

1992-01-01T23:59:59.000Z

150

High pressure furnace  

DOE Patents (OSTI)

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.

Morris, D.E.

1993-09-14T23:59:59.000Z

151

High pressure storage vessel  

DOE Patents (OSTI)

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.

Liu, Qiang

2013-08-27T23:59:59.000Z

152

pressure | OpenEI  

Open Energy Info (EERE)

pressure pressure Dataset Summary Description This raw data reflects readings from instruments mounted on or near a 82 meter meteorological tower located at the National Wind Technology Center (NWTC), approximately 5 miles south of Boulder, CO (specifically: 39.9107 N, 105.2348 W, datum WGS84). The base elevation at the site is 1,855 meters AMSL. Source NREL Date Released Unknown Date Updated March 10th, 2011 (3 years ago) Keywords DOE humidity irrandiance NREL NWTC pressure temperature turbulence wind wind direction wind speed Data text/plain icon Raw data (8/24/2001 - 3/10/2011) (txt, 681 KiB) application/vnd.ms-excel icon Field IDs for above .txt file (xls, 69.6 KiB) Quality Metrics Level of Review Some Review Comment Scientists and Technicians are notified real-time via email of instruments outside the above min/max or delta comparisons (http://www.nrel.gov/midc/nwtc_m2/) Data have not been reviewed for accuracy or completeness; disclaimer available (http://www.nrel.gov/disclaimer.html).

153

Design of a variable-conductance vacuum insulation  

DOE Green Energy (OSTI)

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.

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

1994-01-01T23:59:59.000Z

154

Property:Recirculating | Open Energy Information  

Open Energy Info (EERE)

Recirculating Recirculating Jump to: navigation, search Property Name Recirculating Property Type String Pages using the property "Recirculating" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + No + 10-ft Wave Flume Facility + No + 5 5-ft Wave Flume Facility + No + 6 6-ft Wave Flume Facility + No + A Alden Large Flume + Yes + Alden Small Flume + No + B Bucknell Hydraulic Flume + Yes + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + Yes + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + Yes + Carderock Large Cavitation Tunnel + Yes + Carderock Subsonic Wind Tunnel + Yes + Conte Large Flume + No + Conte Small Flume + No + D DeFrees Flume 1 + No + DeFrees Flume 2 + No + DeFrees Flume 3 + No +

155

Managed Pressure Drilling Candidate Selection  

E-Print Network (OSTI)

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 several drilling problems, including non-productive time and/or drilling flat time issues. These techniques, now sub-classifications of Managed Pressure Drilling, are referred to as 'Variations' and 'Methods' of Managed Pressure Drilling. Although using Managed Pressure Drilling for drilling wells has several benefits, not all wells that seem a potential candidate for Managed Pressure Drilling, need Managed Pressure Drilling. The drilling industry has numerous simulators and software models to perform drilling hydraulics calculations and simulations. Most of them are designed for conventional well hydraulics, while some can perform Underbalanced Drilling calculations, and a select few can perform Managed Pressure Drilling calculations. Most of the few available Managed Pressure Drilling models are modified Underbalanced Drilling versions that fit Managed Pressure Drilling needs. However, none of them focus on Managed Pressure Drilling and its candidate selection alone. An 'Managed Pressure Drilling Candidate Selection Model and software' that can act as a preliminary screen to determine the utility of Managed Pressure Drilling for potential candidate wells are developed as a part of this research dissertation. The model and a flow diagram identify the key steps in candidate selection. The software performs the basic hydraulic calculations and provides useful results in the form of tables, plots and graphs that would help in making better engineering decisions. An additional Managed Pressure Drilling worldwide wells database with basic information on a few Managed Pressure Drilling projects has also been compiled that can act as a basic guide on the Managed Pressure Drilling variation and project frequencies and aid in Managed Pressure Drilling candidate selection.

Nauduri, Anantha S.

2009-05-01T23:59:59.000Z

156

Pressure Data Within BOP- ODS  

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

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

157

Pressure Data Within BOP- XLS  

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

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

158

Low pressure turbine installation  

SciTech Connect

Low-pressure turbine installation is described comprising a casing, at least two groups of turbine stages mounted in said casing, each turbine stage having blades so arranged that a flow of steam passes through the respective turbine stages in contraflow manner, partition means in said casing for separating the opposed final stages of said turbine stages from each other, and steam exhausting means opened in the side walls of said casing in a direction substantially perpendicular to the axis of said turbine, said steam exhausting means being connected to condensers.

Iizuka, N.; Hisano, K.; Ninomiya, S.; Otawara, Y.

1976-08-10T23:59:59.000Z

159

Fiber-optic pressure sensor  

DOE Patents (OSTI)

A pressure wave sensor utilizing fiber optic interferometry techniques to determine pressure in a bar. Light from a fiber optic coil around the bar is mixed with light from a reference optical fiber to produce interference fringes as a function of time. These fringes over time are related to the pressure versus time existing in the bar. 2 figs.

Dingus, R.S.

1989-03-10T23:59:59.000Z

160

Combustor oscillation pressure stabilizer  

DOE Patents (OSTI)

In accordance with the objective of the present invention, the active control of unsteady combustion induced oscillations in a combustion chamber fired by a suitable fuel and oxidizer mixture, such as a hydrocarbon fuel and air mixture, is provided by restructuring and moving the position of the main flame front and thereby increasing the transport time and displacing the pressure wave further away from the in-phase relationship with the periodic heat release. The restructuring and repositioning of the main flame are achieved by utilizing a pilot flame which is pulsed at a predetermined frequency corresponding to less than about one-half the frequency of the combustion oscillation frequency with the duration of each pulse being sufficient to produce adequate secondary thermal energy to restructure the main flame and thereby decouple the heat release from the acoustic coupling so as to lead to a reduction in the dynamic pressure amplitude. The pulsating pilot flame produces a relatively small and intermittently existing flame front in the combustion zone that is separate from the oscillating main flame front but which provides the thermal energy necessary to effectively reposition the location of the oscillating main flame front out of the region in the combustion zone where the acoustic coupling can occur with the main flame and thereby effectively altering the oscillation-causing phase relationship with the heat of combustion.

Gemmen, R.S.; Richards, G.A.; Yip, M.T.J.; Robey, E.; Cully, S.R.; Addis, R.E.

1996-12-31T23:59:59.000Z

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


161

On Sub-ENSO Variability  

Science Conference Proceedings (OSTI)

Multichannel singular spectrum analysis (MSSA) of surface zonal wind, sea surface temperature (SST), 20° isotherm depth, and surface zonal current observations (between 1990 and 2004) identifies three coupled ocean–atmosphere modes of variability ...

Noel S. Keenlyside; Mojib Latif; Anke Dürkop

2007-07-01T23:59:59.000Z

162

Temperature, Humidity, Wind and Pressure Sensors (THWAPS) Handbook  

SciTech Connect

The temperature, humidity, wind, and pressure system (THWAPS) provide surface reference values of these measurements for balloon-borne sounding system (SONDE) launches. The THWAPS is located adjacent to the SONDE launch site at the Southern Great Plains (SGP) Central Facility. The THWAPS system is a combination of calibration-quality instruments intended to provide accurate measurements of meteorological conditions near the surface. Although the primary use of the system is to provide accurate surface reference values of temperature, pressure, relative humidity (RH), and wind velocity for comparison with radiosonde readings, the system includes a data logger to record time series of the measured variables.

Ritsche, MT

2011-01-17T23:59:59.000Z

163

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

Science Conference Proceedings (OSTI)

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.

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

2012-01-01T23:59:59.000Z

164

Interannual Variability of the Global Radiation Budget  

Science Conference Proceedings (OSTI)

Interannual variability of the global radiation budget, regions that contribute to its variability, and what limits albedo variability are investigated using Clouds and the Earth’s Radiant Energy System (CERES) data taken from March 2000 through ...

Seiji Kato

2009-09-01T23:59:59.000Z

165

CDIAC Atmospheric Pressure Data Sets  

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

Atmospheric Pressure Atmospheric Pressure CDIAC Climate Holdings Containing Atmospheric Pressure Data Global Data Sets Data Set Name Investigators Data Type/Format Period of Record Global Historical Climatology Network (GHCN); Vs. 1 (CDIAC NDP-041) R.S. Vose et al. Surface stations; monthly mean sea-level pressure Varies by station; through 1990 Extended Edited Synoptic Cloud Reports from Ships and Land Stations Over the Globe, 1952-2009 (CDIAC NDP-026C) C.J. Hahn, S.G. Warren, and R. Eastman Six-hourly synoptic observations of sea-level pressure Land 1971-2009; Ocean 1952-2008 Global Historical Climatology Network (GHCN); Vs. 2 (Note: the above link takes you to NOAA's National Climatic Data Center website.) R.S. Vose et al. Surface stations; monthly mean sea-level pressure Varies by station; some through most recent month

166

Variable focal length deformable mirror  

DOE Patents (OSTI)

A variable focal length deformable mirror has an inner ring and an outer ring that simply support and push axially on opposite sides of a mirror plate. The resulting variable clamping force deforms the mirror plate to provide a parabolic mirror shape. The rings are parallel planar sections of a single paraboloid and can provide an on-axis focus, if the rings are circular, or an off-axis focus, if the rings are elliptical. The focal length of the deformable mirror can be varied by changing the variable clamping force. The deformable mirror can generally be used in any application requiring the focusing or defocusing of light, including with both coherent and incoherent light sources.

Headley, Daniel (Albuquerque, NM); Ramsey, Marc (Albuquerque, NM); Schwarz, Jens (Albuquerque, NM)

2007-06-12T23:59:59.000Z

167

Computer Based Training: Pressure Measurement  

Science Conference Proceedings (OSTI)

ETTM Pressure Measurement is a computer based training module that allows users to access training when desired and review it at their own pace. It provides graphics and limited interactive features to enhance learning. The purpose of this training module is to provide an understanding of the engineering principles associated with pressure measurement through the review of: Definitions and laws, Operation of some typical plant pressure instruments and, Installation and correction considerations that will...

2010-11-12T23:59:59.000Z

168

A Deep-Sea Differential Pressure Gauge  

Science Conference Proceedings (OSTI)

A pressure gauge configured to respond to the difference between the ocean pressure and the pressure within a confined volume of compressible oil is found to be especially useful for detecting pressure fluctuations in the frequency range from a ...

Charles Cox; Thomas Deaton; Spahr Webb

1984-09-01T23:59:59.000Z

169

Energy Systems High Pressure Test Laboratory (Fact Sheet)  

Science Conference Proceedings (OSTI)

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.

Not Available

2011-10-01T23:59:59.000Z

170

High Pressure Studies of Superconductivity.  

E-Print Network (OSTI)

??Superconductivity has been studied extensively since it was first discovered over 100 years ago. High pressure studies, in particular, have been vital in furthering our… (more)

Hillier, Narelle Jayne

2013-01-01T23:59:59.000Z

171

Coherence of Western Boundary Pressure at the RAPID WAVE Array: Boundary Wave Adjustments or Deep Western Boundary Current Advection?  

Science Conference Proceedings (OSTI)

This study investigates the coherence between ocean bottom pressure signals at the Rapid Climate Change programme (RAPID) West Atlantic Variability Experiment (WAVE) array on the western North Atlantic continental slope, including the Woods Hole ...

Shane Elipot; Chris Hughes; Sofia Olhede; John Toole

2013-04-01T23:59:59.000Z

172

CONTAM Libraries - Appendix B: CONTAM Wind Pressure ...  

Science Conference Proceedings (OSTI)

... Appendix B: CONTAM Wind Pressure Profile Library. The table below contains information on the wind pressure profiles ...

173

High pressure heterogeneous catalysis in a low pressure UHV environment  

SciTech Connect

The major thrust of our research is to carry out for the first time a heterogeneous catalytic reaction that normally is observed only at high pressures (>1 atm) of reactant gas at low pressures (<10{sup {minus}4} Torr) in an ultrahigh vacuum environment. The reaction we have chosen is the steam reforming of methane on a Ni(111) crystal.

Ceyer, S.T.

1990-01-01T23:59:59.000Z

174

Operating Reserves and Variable Generation  

DOE Green Energy (OSTI)

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.

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

2011-08-01T23:59:59.000Z

175

Electrokinetically pumped high pressure sprays  

DOE Patents (OSTI)

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.

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

2005-11-01T23:59:59.000Z

176

Electrokinetically pumped high pressure sprays  

DOE Patents (OSTI)

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.

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

2002-01-01T23:59:59.000Z

177

NETL: Pressure Swing Absorption Device  

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

Pressure Swing Absorption Device and Process for Separating CO2 from Shifted Syngas and its Capture for Subsequent Storage Pressure Swing Absorption Device and Process for Separating CO2 from Shifted Syngas and its Capture for Subsequent Storage Project No.: DE-FE0001323 New Jersey Institute of Technology is developing an advanced pressure swing absorption-based (PSAB) device via laboratory-based experiments. The device will be used to accomplish a cyclic process to process low temperature post-shift-reactor synthesis gas resulting from the gasification process into purified hydrogen at high pressure for use by the combustion turbine of an integrated gasification combined cycle (IGCC) plant. The overall goal of the proposed work is to develop an advanced PSAB device and cyclic process for use in a coal-fired IGCC plant to produce purified hydrogen at high pressure and a highly purified CO2 stream suitable for use or sequestration.

178

High-Pressure Hydrogen Tanks  

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

February 8 February 8 th , 2005 Mark J. Warner, P.E. Principal Engineer Quantum Technologies, Inc. Irvine, CA Low Cost, High Efficiency, Low Cost, High Efficiency, High Pressure Hydrogen Storage High Pressure Hydrogen Storage This presentation does not contain any proprietary or confidential information. 70 MPa Composite Tanks Vent Line Ports Defueling Port (optional) Fill Port Filter Check Valve Vehicle Interface Bracket with Stone Shield In Tank Regulator with Solenoid Lock-off Pressure Relief Device Manual Valve Compressed Hydrogen Storage System In-Tank Regulator Pressure Sensor (not visible here) Pressure Relief Device (thermal) In Tank Gas Temperature Sensor Carbon Composite Shell (structural) Impact Resistant Outer Shell (damage resistant) Gas Outlet Solenoid Foam Dome (impact protection)

179

Fundamentals of high pressure adsorption  

Science Conference Proceedings (OSTI)

High-pressure adsorption attracts research interests following the world's attention to alternative fuels, and it exerts essential effect on the study of hydrogen/methane storage and the development of novel materials addressing to the storage. However, theoretical puzzles in high-pressure adsorption hindered the progress of application studies. Therefore, the present paper addresses the major theoretical problems that challenged researchers: i.e., how to model the isotherms with maximum observed in high-pressure adsorption; what is the adsorption mechanism at high pressures; how do we determine the quantity of absolute adsorption based on experimental data. Ideology and methods to tackle these problems are elucidated, which lead to new insights into the nature of high-pressure adsorption and progress in application studies, for example, in modeling multicomponent adsorption, hydrogen storage, natural gas storage, and coalbed methane enrichment, was achieved.

Zhou, Y.P.; Zhou, L. [Tianjin University, Tianjin (China). High Pressure Adsorption Laboratory

2009-12-15T23:59:59.000Z

180

atmospheric pressure | OpenEI  

Open Energy Info (EERE)

pressure pressure Dataset Summary Description (Abstract):Atmospheric Pressure (kPa)NASA Surface meteorology and Solar Energy (SSE) Release 6.0 Data Set (Nov 2007)22-year Monthly & Annual Average (July 1983 - June 2005)Parameter: Atmospheric Pressure (kPa)Internet: http://eosweb.larc.nasa.gov/sse/Note 1: SSE Methodology & Accuracy sections onlineNote 2: Lat/Lon values indicate the lower left corner of a 1x1 degree region. Negative values are south and west; positive values are north and east. Boundaries of the -90/-180 region Source U.S. National Aeronautics and Space Administration (NASA), Surface meteorology and Solar Energy (SSE) Date Released March 31st, 2009 (5 years ago) Date Updated Unknown Keywords atmospheric pressure climate NASA SWERA UNEP Data text/csv icon Download Data (csv, 46 MiB)

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


181

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

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.

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

1999-06-01T23:59:59.000Z

182

Massive Variability Surveys from Venezuela  

E-Print Network (OSTI)

At the Venezuela National Astronomical Observatory we are carrying out variability surveys spanning many hundreds of square degrees near the celestial equator, using an 8k x 8k CCD Mosaic Camera optimized for drift-scanning on a 1m Schmidt telescope. Among the initial efforts was a project to obtain the first moderately deep, homogeneous sample of young stars over an area of ? 180sqr.deg. encompassing the entire Orion OB1 association, one of the nearest and most active regions of star formation. The results show that variability is a powerful technique to identify pre-main sequence populations, specially in sparse areas devoid of gas and dust. We are currently developing a massive database, equipped with web-based data mining tools, that will make our data and results available to the astronomical community. 1.

C. D. Impey; C. E. Petry; César Briceño

2003-01-01T23:59:59.000Z

183

Massive Variability Surveys from Venezuela  

E-Print Network (OSTI)

At the Venezuela National Astronomical Observatory we are carrying out variability surveys spanning many hundreds of square degrees near the celestial equator, using an 8k x 8k CCD Mosaic Camera optimized for drift-scanning on a 1m Schmidt telescope. Among the initial efforts was a project to obtain the first moderately deep, homogeneous sample of young stars over an area of ~180sqr.deg. encompassing the entire Orion OB1 association, one of the nearest and most active regions of star formation. The results show that variability is a powerful technique to identify pre-main sequence populations, specially in sparse areas devoid of gas and dust. We are currently developing a massive database, equipped with web-based data mining tools, that will make our data and results available to the astronomical community.

Briceño, C

2003-01-01T23:59:59.000Z

184

Massive Variability Surveys from Venezuela  

E-Print Network (OSTI)

At the Venezuela National Astronomical Observatory we are carrying out variability surveys spanning many hundreds of square degrees near the celestial equator, using an 8k x 8k CCD Mosaic Camera optimized for drift-scanning on a 1m Schmidt telescope. Among the initial efforts was a project to obtain the first moderately deep, homogeneous sample of young stars over an area of ~180sqr.deg. encompassing the entire Orion OB1 association, one of the nearest and most active regions of star formation. The results show that variability is a powerful technique to identify pre-main sequence populations, specially in sparse areas devoid of gas and dust. We are currently developing a massive database, equipped with web-based data mining tools, that will make our data and results available to the astronomical community.

Cesar Briceno

2003-04-03T23:59:59.000Z

185

Lecture 2227 Continuous Random Variables  

E-Print Network (OSTI)

-x/100 dx = -e-x/100 100 0 = 1 - e-1 = .632 text typo Example 3 (Light Bulb): The lifetime X, in hours, of a certain kind of light bulb is a continuous random variable with density f(x) = 1500 x2 I(1500,) Check = 1 4 = p Let B denote the number of failures before 2000 hours among 5 light bulbs. Then P(B 1) = P

Scholz, Fritz

186

Lecture 2227 Continuous Random Variables  

E-Print Network (OSTI)

) = 100 0 1 100 e-x/100 dx = -e-x/100 100 0 = 1 - e-1 = .632 text typo Example 3 (Light Bulb): The lifetime X, in hours, of a certain kind of light bulb is a continuous random variable with density f 2000 1500 = 1 - 3 4 = 1 4 = p Let B denote the number of failures before 2000 hours among 5 light bulbs

Scholz, Fritz

187

Determining Critical Pressure and Duct Leakage in VAV Air-Handling Units  

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

Determining Critical Pressure and Duct Leakage in VAV Air-Handling Units Determining Critical Pressure and Duct Leakage in VAV Air-Handling Units Speaker(s): Clifford Federspiel Date: December 3, 2003 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Nance Matson Fans for moving air in buildings use a significant amount of energy. It is well known that fan energy use in variable-air-volume (VAV) systems can be reduced by resetting the supply duct pressure. The standard way to reset duct pressure is by controlling the most-open terminal damper to a nearly open position. Most systems can't measure terminal damper positions, so pressures are either not reset at all or use ad hoc resetting strategies that are configured sub-optimally. In this seminar I will describe a new method of determining the critical supply duct pressure for VAV systems.

188

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)

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 to the terminal box and box inlet static pressure. Typically, the air duct static pressure is set as a constant set point based on the system design information and sensor location. However, under partial load conditions, the terminal box dampers have to be closed more since either required airflow is less than the design airflow which directly leads to much less pressure loss. Thus the static pressure set point should be reset lower in order to reduce fan power, avoid noise at terminal box dampers and box damper malfunction due to excessive pressure. Different static pressure reset schedules are reviewed and compared, considering the influence of outside air temperature on the building load, availability of the VAV box damper positions, the airflow ratio based static pressure reset has also applicable advantages over the existing constant static pressure set point and two typical reset methods. This paper present the theoretical models to express the impacts of static pressure reset on fan airflow, fan head, air leakage, fan power and thermal energy for both pressure independent and pressure dependent boxes. The impacts are also demonstrated using the parametric analysis and numerical results to show the benefits of the static pressure reset including reducing fan power, cooling energy and heating energy.

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

2007-01-01T23:59:59.000Z

189

Electrokinetic high pressure hydraulic system  

DOE Patents (OSTI)

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.

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

2000-01-01T23:59:59.000Z

190

Self pressuring HTP feed systems  

DOE Green Energy (OSTI)

Hydrogen peroxide tanks can be pressurized with decomposed HTP (high test hydrogen peroxide) originating in the tank itself. In rocketry, this offers the advantage of eliminating bulky and heavy inert gas storage. Several prototype self-pressurizing HTP systems have recently been designed and tested. Both a differential piston tank and a small gas-driven pump have been tried to obtain the pressure boost needed for flow through a gas generator and back to the tank. Results include terrestrial maneuvering tests of a prototype microsatellite, including warm gas attitude control jets.

Whitehead, J.

1999-10-14T23:59:59.000Z

191

Comparison of pressure ransient response in intensely and sparsely fractured reservoirs  

DOE Green Energy (OSTI)

A comprehensive analytical model is presented to study the pressure transient behavior of a naturally fractured reservoir with a continuous matrix block size distribution. Geologically realistic probability density functions of matrix block size are used to represent reservoirs of varying fracture intensity and uniformity. Transient interporosity flow is assumed and interporosity skin is incorporated. Drawdown and interference pressure transient tests are investigated. The results show distinctions in the pressure response from intensely and sparsely fractured reservoirs in the absence of interporosity skin. Also, uniformly and nonuniformly fractured reservoirs exhibit distinct responses, irrespective of the degree of fracture intensity. The pressure response in a nonuniformly fractured reservoir with large block size variability, approaches a nonfractured (homogeneous) reservoir response. Type curves are developed to estimate matrix block size variability and the degree of fracture intensity from drawdown and interference well tests.

Johns, R.T.

1989-01-01T23:59:59.000Z

192

Comparison of pressure transient response in intensely and sparsely fractured reservoirs  

DOE Green Energy (OSTI)

A comprehensive analytical model is presented to study the pressure transient behavior of a naturally fractured reservoir with a continuous matrix block size distribution. Geologically realistic probability density functions of matrix block size are used to represent reservoirs of varying fracture intensity and uniformity. Transient interporosity flow is assumed and interporosity skin is incorporated. Drawdown and interference pressure transient tests are investigated. The results show distinctions in the pressure response from intensely and sparsely fractured reservoirs in the absence of interporosity skin. Also, uniformly and nonuniformly fractured reservoirs exhibit distinct responses, irrespective of the degree of fracture intensity. The pressure response in a nonuniformly fractured reservoir with large block size variability, approaches a nonfractured (homogeneous) reservoir response. Type curves are developed to estimate matrix block size variability and the degree of fracture intensity from drawdown and interference well tests.

Johns, R.T.

1989-04-01T23:59:59.000Z

193

The Use of Pressure and Strain as Processing Variables in Soft ...  

Science Conference Proceedings (OSTI)

... and large saturation induction, making them attractive materials for use in power ... Magnetic Materials for Use in Energy-efficient Distribution Transformers.

194

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

E-Print Network (OSTI)

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.

Liu, Weiqun; Li, Yushou; Wang, Bo

2010-01-01T23:59:59.000Z

195

Variablity among electronic cigarettes in the pressure drop, airflow rate, and aerosol production  

E-Print Network (OSTI)

OH), (b) Crown Seven Hydro Im- perial with USA blenda brand. Crown Seven Hydro Imperial and Smoking EverywhereStix #2, VapCigs #2, Crown Seven Hydro Imperial, and Smoking

Talbot, Prue

2013-01-01T23:59:59.000Z

196

HEART RATE AND BLOOD PRESSURE VARIABILITY UNDER MOON, MARS AND ZERO GRAVITY CONDITIONS DURING PARABOLIC FLIGHTS  

E-Print Network (OSTI)

PARABOLIC FLIGHTS Wouter Aerts1 , Pieter Joosen1 , Devy Widjaja1,2 , Carolina Varon1,2 , Steven Vandeput1, Belgium, Email: andre.aubert@med.kuleuven.be ABSTRACT Gravity changes during partial-G parabolic flights requires the understanding of how the CVS adapts to gravity changes. Parabolic flights are one

197

Electrokinetic high pressure hydraulic system  

DOE Patents (OSTI)

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.

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

198

Low-Pressure Sodium Lighting  

Energy.gov (U.S. Department of Energy (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...

199

Low pressure carbonylation of heterocycles  

Science Conference Proceedings (OSTI)

Heterocycles, e.g., epoxides, are carbonylated at low pressure with high percentage conversion to cyclic, ring expanded products using the catalyst ##STR00001## where L is tetrahydrofuran (THF).

Coates, Geoffrey W. (Lansing, NY); Kramer, John W. (Mt. Pleasant, MI); Schmidt, Joseph A. R. (Sylvania, OH)

2011-01-25T23:59:59.000Z

200

Low pressure carbonylation of heterocycles  

Science Conference Proceedings (OSTI)

Heterocycles, e.g., epoxides, are carbonylated at low pressure with high percentage conversion to cyclic, ring expanded products using the catalyst ##STR00001## where L is tetrahydrofuran (THF).

Coates, Geoffrey W. (Ithaca, NY); Kramer, John (Ithaca, NY)

2009-08-04T23:59:59.000Z

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


201

Studying Materials Under Extreme Pressure  

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

Studying Materials Under Extreme Pressure Studying Materials Under Extreme Pressure Coupling undulator radiation from Advanced Photon Source (APS) beamlines 3-ID and 13-ID to nuclear resonant inelastic scattering techniques, researchers have determined the phonon density of states for iron under pressures up to 153 gigapascals, equivalent to those found at the Earth's core. Image of the Earth's core. Although indirect measurements and theory have, since the early 1950s, produced an informed picture of the structure and composition of the materials that make up the core of the Earth, direct proof and the answers to some intriguing questions remain unanswered. Previously, ultrahigh-pressure experiments using nuclear resonant inelastic scattering have been difficult to carry out due the tiny samples required.

202

High pressure synthesis gas fermentation  

DOE Green Energy (OSTI)

The construction of the high pressure gas phase fermentation system has been completed. Photographs of the various components of the system are presented, along with an operating procedure for the equipment.

Not Available

1992-01-01T23:59:59.000Z

203

Quantum computation and hidden variables  

E-Print Network (OSTI)

Many physicists limit oneself to an instrumentalist description of quantum phenomena and ignore the problems of foundation and interpretation of quantum mechanics. This instrumentalist approach results to "specialization barbarism" and mass delusion concerning the problem, how a quantum computer can be made. The idea of quantum computation can be described within the limits of quantum formalism. But in order to understand how this idea can be put into practice one should realize the question: "What could the quantum formalism describe?", in spite of the absence of an universally recognized answer. Only a realization of this question and the undecided problem of quantum foundations allows to see in which quantum systems the superposition and EPR correlation could be expected. Because of the "specialization barbarism" many authors are sure that Bell proved full impossibility of any hidden-variables interpretation. Therefore it is important to emphasize that in reality Bell has restricted to validity limits of the no- hidden-variables proof and has shown that two-state quantum system can be described by hidden variables. The later means that no experimental result obtained on two-state quantum system can prove the existence of superposition and violation of the realism. One should not assume before unambiguous experimental evidence that any two-state quantum system is quantum bit. No experimental evidence of superposition of macroscopically distinct quantum states and of a quantum bit on base of superconductor structure was obtained for the present. Moreover same experimental results can not be described in the limits of the quantum formalism.

V. V. Aristov; A. V. Nikulov

2010-07-12T23:59:59.000Z

204

Nonferromagnetic linear variable differential transformer  

DOE Patents (OSTI)

A nonferromagnetic linear variable differential transformer for accurately measuring mechanical displacements in the presence of high magnetic fields is provided. The device utilizes a movable primary coil inside a fixed secondary coil that consists of two series-opposed windings. Operation is such that the secondary output voltage is maintained in phase (depending on polarity) with the primary voltage. The transducer is well-suited to long cable runs and is useful for measuring small displacements in the presence of high or alternating magnetic fields.

Ellis, James F. (Powell, TN); Walstrom, Peter L. (Oak Ridge, TN)

1977-06-14T23:59:59.000Z

205

History matching pressure response functions from production data  

E-Print Network (OSTI)

This dissertation presents several new techniques for the analysis of the long-term production performance of tight gas wells. The main objectives of this work are to determine pressure response function for long-term production for a the slightly compressible liquid case, to determine the original gas in place (OGIP) during pseudosteady state (PSS), to determine OGIP in the transient period, and to determine the effects of these parameters on linear flow in gas wells. Several methods are available in the industry to analyze the production performance of gas wells. One common method is superposition time. This method has the advantage of being able to analyze variable-rate and variable-pressure data, which is usually the nature of field data. However, this method has its shortcomings. In this work, simulation and field cases illustrate the shortcomings of superposition. I present a new normalized pseudotime plotting function for use in the superposition method to smooth field data and more accurately calculate OGIP. The use of this normalized pseudotime is particularly important in the analysis of highly depleted reservoirs with large change in total compressibility where the superposition errors are largest. The new tangent method presented here can calculate the OGIP with current reservoir properties for both constant rate and bottomhole flowing pressure (pwf) production. In this approach pressure-dependent permeability data can be integrated into a modified real gas pseudopressure,m(p), which linearizes the reservoir flow equations and provides correct values for permeability and skin factor. But if the customary real-gas pseudopressure, m(p) is used instead, erroneous values for permeability and skin factor will be calculated. This method uses an exponential equation form for permeability vs. pressure drop. Simulation and field examples confirm that the new correction factor for the rate dependent problem improves the linear model for both PSS and transient period, whether plotted on square-root of time or superposition plots.

Ibrahim, Mazher Hassan

2004-12-01T23:59:59.000Z

206

Seafloor Pressure Measurements of Nonlinear Internal Waves  

Science Conference Proceedings (OSTI)

Highly resolved pressure measurements on the seafloor over New Jersey’s continental shelf reveal the pressure signature of nonlinear internal waves of depression as negative pressure perturbations. The sign of the perturbation is determined by ...

J. N. Moum; J. D. Nash

2008-02-01T23:59:59.000Z

207

Spray bottle apparatus with pressure multiplying pistons  

DOE Patents (OSTI)

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.

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

1990-01-01T23:59:59.000Z

208

DETECTING VARIABILITY IN MASSIVE ASTRONOMICAL TIME-SERIES DATA. II. VARIABLE CANDIDATES IN THE NORTHERN SKY VARIABILITY SURVEY  

SciTech Connect

We present variability analysis of data from the Northern Sky Variability Survey (NSVS). Using the clustering method, which defines variable candidates as outliers from large clusters, we cluster 16,189,040 light curves having data points at more than 15 epochs as variable and non-variable candidates in 638 NSVS fields. Variable candidates are selected depending on how strongly they are separated from the largest cluster and how rarely they are grouped together in eight-dimensional space spanned by variability indices. All NSVS light curves are also cross-correlated with IRAS, AKARI, Two Micron All Sky Survey, Sloan Digital Sky Survey (SDSS), and GALEX objects, as well as known objects in the SIMBAD database. The variability analysis and cross-correlation results are provided in a public online database, which can be used to select interesting objects for further investigation. Adopting conservative selection criteria for variable candidates, we find about 1.8 million light curves as possible variable candidates in the NSVS data, corresponding to about 10% of our entire NSVS sample. Multi-wavelength colors help us find specific types of variability among the variable candidates. Moreover, we also use morphological classification from other surveys such as SDSS to suppress spurious cases caused by blending objects or extended sources due to the low angular resolution of the NSVS.

Shin, Min-Su [Department of Astronomy, The University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States); Yi, Hahn; Kim, Dae-Won; Chang, Seo-Won [Department of Astronomy, Yonsei University, Seoul 120-749 (Korea, Republic of); Byun, Yong-Ik, E-mail: msshin@umich.edu, E-mail: yihahn@galaxy.yonsei.ac.kr, E-mail: dakim@cfa.harvard.edu, E-mail: seowony@galaxy.yonsei.ac.kr, E-mail: ybyun@yonsei.ac.kr [Department of Astronomy and University Observatory, Yonsei University, Seoul 120-749 (Korea, Republic of)

2012-03-15T23:59:59.000Z

209

Modeling the Effect of Land Surface Evaporation Variability on Precipitation Variability. Part I: General Response  

Science Conference Proceedings (OSTI)

This is the first of a two-part article that investigates the impact of land surface evaporation variability on the interannual variability of precipitation and compares it with the impact caused by sea surface temperature variability. Previous ...

Oreste Reale; Paul Dirmeyer

2002-08-01T23:59:59.000Z

210

Variable Average Absolute Percent Differences  

U.S. Energy Information Administration (EIA) Indexed Site

Variable Variable Average Absolute Percent Differences Percent of Projections Over- Estimated Gross Domestic Product Real Gross Domestic Product (Average Cumulative Growth)* (Table 2) 1.0 42.6 Petroleum Imported Refiner Acquisition Cost of Crude Oil (Constant $) (Table 3a) 35.2 18.6 Imported Refiner Acquisition Cost of Crude Oil (Nominal $) (Table 3b) 34.7 19.7 Total Petroleum Consumption (Table 4) 6.2 66.5 Crude Oil Production (Table 5) 6.0 59.6 Petroleum Net Imports (Table 6) 13.3 67.0 Natural Gas Natural Gas Wellhead Prices (Constant $) (Table 7a) 30.7 26.1 Natural Gas Wellhead Prices (Nominal $) (Table 7b) 30.0 27.1 Total Natural Gas Consumption (Table 8) 7.8 70.2 Natural Gas Production (Table 9) 7.1 66.0 Natural Gas Net Imports (Table 10) 29.3 69.7 Coal Coal Prices to Electric Generating Plants (Constant $)** (Table 11a)

211

Variable frequency microwave furnace system  

DOE Patents (OSTI)

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.

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

1994-06-14T23:59:59.000Z

212

Sources of Variability of Evapotranspiration in California  

Science Conference Proceedings (OSTI)

The variability (1990–2002) of potential evapotranspiration estimates (ETo) and related meteorological variables from a set of stations from the California Irrigation Management System (CIMIS) is studied. Data from the National Climatic Data ...

Hugo G. Hidalgo; Daniel R. Cayan; Michael D. Dettinger

2005-02-01T23:59:59.000Z

213

Incremental Closure of Free Variable Tableaux  

Science Conference Proceedings (OSTI)

This paper presents a technique for automated theorem proving with free variable tableaux that does not require backtracking. Most existing automated proof procedures using free variable tableaux require iterative deepening and backtracking over applied ...

Martin Giese

2001-06-01T23:59:59.000Z

214

Thermocline Variability in Different Dynamic Regions  

Science Conference Proceedings (OSTI)

The response of thermocline circulation to a variable wind forcing is investigated with quasigeostrophic models. The physical mechanism responsible for the different variability features in various dynamic regions has been highlighted. Special ...

Zhengye Liu

1996-08-01T23:59:59.000Z

215

Cryogenic Pressure Vessels: Progress and Plans  

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

Pressure Vessel workshop, LLNL, February 15, 2011, p. 1 Cryogenic Pressure Vessels: Progress and Plans Salvador Aceves, Gene Berry, Francisco Espinosa, Ibo Matthews, Guillaume...

216

Studies on selection of controlled variables  

E-Print Network (OSTI)

Studies on selection of controlled variables by Vidar Alstad A Thesis Submitted for the Degree. Thus, the selection of controlled variables integrates the optimization and the control layer. Selecting the right controlled variables can be of paramount importance. Many chem­ ical processes

Skogestad, Sigurd

217

Studies on selection of controlled variables  

E-Print Network (OSTI)

Studies on selection of controlled variables by Vidar Alstad A Thesis Submitted for the Degree. Thus, the selection of controlled variables integrates the optimization and the control layer. Selecting the right controlled variables can be of paramount importance. Many chem- ical processes

Skogestad, Sigurd

218

Adaptive sampling for Bayesian variable selection  

E-Print Network (OSTI)

Adaptive sampling for Bayesian variable selection DAVID J. NOTT Department of Statistics for variable selection and for dealing with model un- certainty have become increasingly popular in recent consider adaptive Markov chain Monte Carlo schemes for Bayesian variable selection in Gaussian linear

Blennerhassett, Peter

219

High pressure liquid level monitor  

DOE Patents (OSTI)

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.

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

1984-01-01T23:59:59.000Z

220

Melting of Ice under Pressure  

SciTech Connect

The melting of ice under pressure is investigated with a series of first principles molecular dynamics simulations. In particular, a two-phase approach is used to determine the melting temperature of the ice-VII phase in the range of 10 to 50 GPa. Our computed melting temperatures are consistent with existing diamond anvil cell experiments. We find that for pressures between 10 to 40 GPa, ice melts as a molecular solid. For pressures above {approx}45 GPa there is a sharp increase in the slope of the melting curve due to the presence of molecular dissociation and proton diffusion in the solid, prior to melting. The onset of significant proton diffusion in ice-VII as a function of increasing temperature is found to be gradual and bears many similarities to that of a type-II superionic solid.

Schwegler, E; Sharma, M; Gygi, F; Galli, G

2008-07-31T23:59:59.000Z

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


221

Variable ratio regenerative braking device  

DOE Patents (OSTI)

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.

Hoppie, Lyle O. (Birmingham, MI)

1981-12-15T23:59:59.000Z

222

Variable residence time vortex combustor  

DOE Patents (OSTI)

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

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

1987-01-01T23:59:59.000Z

223

Rapid Oscillations in Cataclysmic Variables  

E-Print Network (OSTI)

I give an overview of the rich phenomenology of dwarf nova oscillations (DNOs) and Quasi-periodic Oscillations (QPOs) observed in cataclysmic variable stars (CVs). The favoured interpretation of these rapid brightness modulations (3 - >1000 s time scales) is that they are magnetic in nature - magnetically channelled accretion from the inner accretion disc for DNOs and possible magnetically excited travelling waves in the disc for QPOs. There is increasing evidence for the magnetic aspects, which extend to lower field the well known properties of strong field (polars) and intermediate strength field (intermediate polars) CVs. The result is that almost all CVs show the presence of magnetic fields on their white dwarf primaries - though for many the intrinsic field may be locally enhanced by the accretion process itself. There are many parallel behaviours with the QPOs seen in X-Ray binaries, with high and low frequency X-Ray QPOs resembling respectively the DNOs and QPOs in CVs.

Brian Warner

2003-12-06T23:59:59.000Z

224

How to Avoid Overestimating Variable Speed Drive Savings  

E-Print Network (OSTI)

This paper addresses eight factors that can cause incorrect and often excessive savings estimates for pump and fan variable speed drive applications. To avoid overestimating savings: 1. Identify system elements that affect head pressure independently of flow rate. 2. Identify system elements that change head pressure in proportion to less than the square of flow rate. 3. Account for dynamic system elements, especially when in systems with minimum static pressure controls. 4. Consider changes in fan efficiency. 5. Account for decreases in motor efficiency at part load, particularly for smaller motors below about 35 percent load. 6. Recognize that existing part load controls may be more efficient than expected. 7. Account for drive losses. 8. Measure full flow power, rather than assuming it is the same as motor nameplate or design power. For many pump and fan systems, none of the eight factors will apply, or their effects will be negligible. However, analysts should consider their applicability when estimating savings for a particular system. This paper provides tools for accounting for the factors.

Maxwell, J. B.

2005-01-01T23:59:59.000Z

225

SNAP: the Spallation Neutrons and Pressure Diffractometer at...  

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

Spallation Neutrons and Pressure Diffractometer at SNS Spallation Neutrons and Pressure Diffractometer. Spallation Neutrons and Pressure Diffractometer. The SNAP Diffractometer...

226

Hydrogen-bond Dynamics and Fermi Resonance in High-pressure Methane Filled Ice  

DOE Green Energy (OSTI)

High-pressure, variable temperature infrared spectroscopy and first-principles calculations on the methane filled ice structure (MH-III) at high pressures are used to investigate the vibrational dynamics related to pressure induced modifications in hydrogen bonding. Infrared spectroscopy of isotopically dilute solutions of H{sub 2}O in D{sub 2}O is employed together with first-principles calculations to characterize proton dynamics with the pressure induced shortening of hydrogen bonds. A Fermi resonance is identified and shown to dominate the infrared spectrum in the pressure region between 10 and 30 GPa. Significant differences in the effects of the Fermi resonance observed between 10 and 300 K arise from the double-well potential energy surface of the hydrogen bond and quantum effects associated with the proton dynamics.

Klug,D.; Tse, J.; Liu, Z.; Hemley, R.

2006-01-01T23:59:59.000Z

227

Analysis of pressure tests through the use of instantaneous source response concepts  

SciTech Connect

A general method of analysis for pressure transient tests is presented. This technique is based on the pressure response of an instantaneous source and it provides a mean to compute the first and second derivatives of the influence function (unit flow rate response) of the well-reservoir system. This information is basic in identifying the flow regimes occurring during the test. This method eliminates the effect of producing time on pressure buildup data. An explicit and stable procedure is discussed to compute both the derivatives of the influence function and the initial reservoir pressure. This technique is suitable for DST and Repeat Formation Tests as well as for pressure buildup and fall off tests with long shut in period; variable flow rate before shut in can be taken into account. Examples of application are presented.

Cinco-Ley, H.; Kuchuk, F.; Ayoub, J.; Ayestaran, L.; Samaniego, V.F.

1986-01-01T23:59:59.000Z

228

Improving Control of a Dual-Duct Single-Fan Variable Air Volume Systems  

E-Print Network (OSTI)

This paper discusses improved control strategies for dual-duct single-fan variable air volume (VAV) systems. Common control strategy for supply air volume modulation is evaluated, and an improved air volume control strategy that maintains separate cold and hot air duct static pressure set points is presented. The paper also explores the interactions between the cold and hot deck temperatures and duct static pressures, and discusses the impact of non-ideal deck temperature settings on duct static pressures and overall system energy consumption. To compensate the negative impact of non-ideal cold and hot deck temperature set points, the authors propose using real-time duct static pressure readings as feedback signals to fine-tune the deck temperature set points. These new control schemes can reduce simultaneous cooling and heating while reducing fan power consumption.

Wei, G.; Martinez, J.; Minihan, T.; Brundidge, T.; Claridge, D. E.; Turner, W. D.

2003-01-01T23:59:59.000Z

229

Efficient Low-Lift Cooling with Radiant Distribution, Thermal Storage and Variable-Speed Chiller Controls Part I: Component and Subsystem Models  

DOE Green Energy (OSTI)

this paper develops component and subsystem models used to evaluat4e the performance of a low-lift cooling system with an air-colled chiller optimized for variable-speed and low-pressure-ratio operation, a hydronic radient distribution system, variable-speed transport miotor controls, and peak-shifting controls.

Armstrong, Peter; Jiang, Wei; Winiarski, David W.; Katipamula, Srinivas; Norford, L. K.; Willingham, ryan

2009-03-31T23:59:59.000Z

230

Stirling engine with pressurized crankcase  

DOE Patents (OSTI)

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.

Corey, John A. (Melrose, NY)

1988-01-01T23:59:59.000Z

231

INVESTIGATIONS ON THE WELDING OF 1-INCH N.B. 18/13/1 STAINLESS STEEL PIPE BY THE HOT PRESSURE WELDING METHOD  

SciTech Connect

An investigation was made on hot pressure welding of 1-in. stainless steel pipe. The application of welding variables and their effect on welding are discussed. (J. E. D.)

O' Grady, G.; Richardson, E.K.

1952-06-30T23:59:59.000Z

232

Simulations of Mesoscale Circulations in the Center of the Iberian Peninsula for Thermal Low Pressure Conditions. Part II: Air-Parcel Transport Patterns  

Science Conference Proceedings (OSTI)

This paper discusses the variability of air-parcel transport under similar summer thermal low pressure conditions over the Iberian Peninsula. Three-dimensional trajectories were estimated by means of the Topography Vorticity-Mode Mesoscale model. ...

Fernando Martín; Magdalena Palacios; Sylvia N. Crespí

2001-05-01T23:59:59.000Z

233

Numerical investigations on the pressure wave absorption and the gas cooling interacting in a  

E-Print Network (OSTI)

1 Numerical investigations on the pressure wave absorption and the gas cooling interacting understanding of the physical phenomena involved, as for example the cooling and the shock wave absorption volume method, variable porosity, arc cooling I. INTRODUCTION Medium voltage cells have to be designed

Sart, Remi

234

Cavitation Erosion of Francis Turbines  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2013. Symposium, Advances in Hydroelectric Turbine Manufacturing and Repair. Presentation ...

235

Hard X-ray Variability of AGN  

E-Print Network (OSTI)

Aims: Active Galactic Nuclei are known to be variable throughout the electromagnetic spectrum. An energy domain poorly studied in this respect is the hard X-ray range above 20 keV. Methods: The first 9 months of the Swift/BAT all-sky survey are used to study the 14 - 195 keV variability of the 44 brightest AGN. The sources have been selected due to their detection significance of >10 sigma. We tested the variability using a maximum likelihood estimator and by analysing the structure function. Results: Probing different time scales, it appears that the absorbed AGN are more variable than the unabsorbed ones. The same applies for the comparison of Seyfert 2 and Seyfert 1 objects. As expected the blazars show stronger variability. 15% of the non-blazar AGN show variability of >20% compared to the average flux on time scales of 20 days, and 30% show at least 10% flux variation. All the non-blazar AGN which show strong variability are low-luminosity objects with L(14-195 keV) < 1E44 erg/sec. Conclusions: Concerning the variability pattern, there is a tendency of unabsorbed or type 1 galaxies being less variable than the absorbed or type 2 objects at hardest X-rays. A more solid anti-correlation is found between variability and luminosity, which has been previously observed in soft X-rays, in the UV, and in the optical domain.

V. Beckmann; S. D. Barthelmy; T. J. -L. Courvoisier; N. Gehrels; S. Soldi; J. Tueller; G. Wendt

2007-09-14T23:59:59.000Z

236

Deconvolution of variable rate reservoir performance data using B-splines  

E-Print Network (OSTI)

This work presents the development, validation and application of a novel deconvolution method based on B-splines for analyzing variable-rate reservoir performance data. Variable-rate deconvolution is a mathematically unstable problem which has been under investigation by many researchers over the last 35 years. While many deconvolution methods have been developed, few of these methods perform well in practice - and the importance of variable-rate deconvolution is increasing due to applications 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 data without generating instability in the deconvolution process. We propose representing the derivative of unknown unit rate drawdown pressure as a weighted sum of Bsplines (with logarithmically distributed knots). We then apply the convolution theorem in the Laplace domain with the input rate and obtain the sensitivities of the pressure response with respect to individual B-splines after numerical inversion of the Laplace transform. The sensitivity matrix is then used in a regularized least-squares procedure to obtain the unknown coefficients of the B-spline representation of the unit rate response or the well testing pressure derivative function. We have also implemented a physically sound regularization scheme into our deconvolution procedure for handling higher levels of noise and systematic errors. We validate our method with synthetic examples generated with and without errors. The new method can recover the unit rate drawdown pressure response and its derivative to a considerable extent, even when high levels of noise are present in both the rate and pressure observations. We also demonstrate the use of regularization and provide examples of under and over-regularization, and we discuss procedures for ensuring proper regularization. Upon validation, we then demonstrate our deconvolution method using a variety of field cases. Ultimately, the results of our new variable-rate deconvolution technique suggest that this technique has a broad applicability in pressure transient/production data analysis. The goal of this thesis is to demonstrate that the combined approach of B-splines, Laplace domain convolution, least-squares error reduction, and regularization are innovative and robust; therefore, the proposed technique has potential utility in the analysis and interpretation of reservoir performance data.

Ilk, Dilhan

2005-12-01T23:59:59.000Z

237

Definition: Variable Peak Pricing | Open Energy Information  

Open Energy Info (EERE)

Variable Peak Pricing Variable Peak Pricing Jump to: navigation, search Dictionary.png Variable Peak Pricing Variable Peak Pricing (VPP) is a hybrid of time-of-use and real-time pricing where the different periods for pricing are defined in advance (e.g., on-peak=6 hours for summer weekday afternoon; off-peak= all other hours in the summer months), but the price established for the on-peak period varies by utility and market conditions.[1] Related Terms real-time pricing References ↑ https://www.smartgrid.gov/category/technology/variable_peak_pricing [[C LikeLike UnlikeLike You like this.Sign Up to see what your friends like. ategory: Smart Grid Definitionssmart grid,off-peak,on-peak,smart grid, |Template:BASEPAGENAME]]smart grid,off-peak,on-peak,smart grid, Retrieved from "http://en.openei.org/w/index.php?title=Definition:Variable_Peak_Pricing&oldid=50262

238

Variability of accretion flow in the core of the Seyfert galaxy NGC 4151  

E-Print Network (OSTI)

We analyze observations of the Seyfert galaxy NGC 4151 covering 90 years in the optical band and 27 years in the 2-10 keV X-ray band. We compute the Normalized Power Spectrum Density (NPSD), the Structure Function (SF) and the Autocorrelation Function (ACF) for these data. The results show that the optical and X-ray variability properties are significantly different. X-ray variations are predominantly in the timescale range of 5 - 1000 days. The optical variations have also a short timescale component which may be related to X-ray variability but the dominant effect is the long timescale variability, with timescales longer than $\\sim$ 10 years. We compare our results with observations of NGC 5548 and Cyg X-1. We conclude that the long timescale variability may be caused by radiation pressure instability in the accretion disk, although the observed timescale in NGC 4151 is by a factor of few longer than expected. X-ray variability of this source is very similar to what is observed in Cyg X-1 but scaled with the mass of the black hole, which suggests that the radiation pressure instability does not affect considerably the X-ray production.

B. Czerny; V. T. Doroshenko; M. Nikolajuk; A. Schwarzenberg-Czerny; Z. Loska; G. Madejski

2001-10-31T23:59:59.000Z

239

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

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

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

240

The use of 'race' as a variable in biomedical research  

E-Print Network (OSTI)

a variable in biomedical research but mainly to monitor thea Variable in Biomedical Research A dissertation submittedVariable in Biomedical Research…………. Manifest, Operative and

Efstathiou, Sophia

2009-01-01T23:59:59.000Z

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


241

Monitoring of Photovoltaic Plant Output and Variability  

Science Conference Proceedings (OSTI)

The performance of photovoltaic (PV) systems, including variability characteristics, is of increasing interest to utilities as they integrate more solar energy onto the electric grid. This study is part of a multi-year research series to investigate influencing factors that affect PV plant output, variability, and approaches to system management. It explores PV variability both from a grid perspective and through examination of project design aspects that can affect annual power production. ...

2012-12-12T23:59:59.000Z

242

Pressure vessel and piping codes  

SciTech Connect

Section III of the ASME Boiler and Pressure Vessel Code contains simplified design formulas for placing bounds on the plastic deformations in nuclear power plant piping systems. For Class 1 piping a simple equation is given in terms of primary load stress indices (B/sub 1/ and B/sub 2/) and nominal pressure and bending stresses. The B/sub 1/ and B/sub 2/ stress indices reflect the capacities of various piping products to carry load without gross plastic deformation. In this paper, the significance of the indices, nominal stresses, and limits given in the Code for Class 1 piping and corresponding requirements for Class 2 and Class 3 piping are discussed. Motivation behind recent (1978-1981) changes in the indices and in the associated stress limits is presented.

Moore, S.E.; Rodabaugh, E.C.

1982-11-01T23:59:59.000Z

243

Ambient pressure fuel cell system  

DOE Patents (OSTI)

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.

Wilson, Mahlon S. (Los Alamos, NM)

2000-01-01T23:59:59.000Z

244

Recent developments in pressure coring  

SciTech Connect

The current rapid growth in the number of enhanced oil and gas recovery projects has created a strong demand for reservoir data such as true residual oil saturations. The companies providing pressure coring services have moved to fill this need. Two recent developments have emerged with the potential of significantly improving the present performance of pressure coring. Coring bits utilizing synthetic diamond cutters have demonstrated coring rates of one-foot per minute while improving core recovery. It is also apparent that cores of a near-unconsolidated nature are more easily recovered. In addition, a special low invasion fluid that is placed in the core retriever has demonstrated reduced core washing by the drilling mud and a decrease in the complexity of preparing cores for analysis. This paper describes the design, laboratory, and field testing efforts that led to these coring improvements. Also, experience in utilizing these developments while recovering over 100 cores is discussed.

McFall, A. L.

1980-01-01T23:59:59.000Z

245

Natural Gas Variability In California: Environmental Impacts...  

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

Natural Gas Variability In California: Environmental Impacts And Device Performance, Combustion Modeling of Pollutant Emissions From a Residential Cooking Range Title Natural Gas...

246

NREL: Transmission Grid Integration - Variability of Renewable...  

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

as variable generation sources because their electricity production varies based on the availability of wind and sun. However, they are not the only source of variation in a...

247

Variable-Period Undulators for Synchrotron Radiation  

DOE Patents (OSTI)

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.

Shenoy, Gopal; Lewellen, John; Shu, Deming; Vinokurov, Nikolai

2005-02-22T23:59:59.000Z

248

High pressure xenon ionization detector  

DOE Patents (OSTI)

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.

Markey, John K. (New Haven, CT)

1989-01-01T23:59:59.000Z

249

High pressure xenon ionization detector  

DOE Patents (OSTI)

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 to 30 C. 2 figs.

Markey, J.K.

1989-11-14T23:59:59.000Z

250

Impacts of Static Pressure Set Level on the HVAC Energy Consumption and Indoor Conditions  

E-Print Network (OSTI)

Air static pressure must be maintained at a certain level leaving the air-handing unit (AHU) to force a suitable amount of air through the terminal boxes. However, an excessive static pressure level is often used due to ( 1 ) lack of a control device in a constant volume system (CV); (2) malfunctioning control device in a variable volume (VAV) system; and (3) fear of failure to maintain room temperature. High static pressure often develops excessive damper leakage in older mixing boxes. This results in an inappropriate mixing of hot and cold air and an excessive amount of air entering the space. Consequently, the actual fan power, heating and cooling energy consumption all become significantly higher than the design values. Even worse, the system may not be able to maintain room conditions due to unwanted simultaneous heating and cooling, and may be noisy due to the excessive static pressure. This paper proposes to control the hot duct pressure and the Variable Frequency Drives ( VFD's) to control the fan static i.e. the cold duct pressure. Both a theoretical analysis and a case study results are presented in this paper.

Liu, M.; Zhu, Y.; Claridge, D. E.; White, E.

1996-01-01T23:59:59.000Z

251

Observational Constraints of New Variable Modified Chaplygin Gas Model  

E-Print Network (OSTI)

Assuming the flat FRW universe in Einstein's gravity filled with New Variable Modified Chaplygin gas (NVMCG) dark energy and dark matter having negligible pressure. In this research work we analyze the viability on the basis of recent observation. Hubble parameter $H$ is expressed in terms of the observable parameters $H_0$, $\\Omega_m^0$ and the model parameters $A_0$, $B_0$, $C_0$, $m$, $n$, $\\alpha$ and the red shift parameter $z$. Here we find a best fitted parameter range of $A_0$, $B_0$ keeping $0\\leq \\alpha \\leq 1$ and using Stern data set (12 points) by minimizing the $\\chi^2$ test at 66%, 90% and 99% confidence levels. Next we do the joint analysis with BAO and CMB observations. Again evaluating the distance modulus $\\mu(z)$ vs redshift ($z$) curve obtained in the model NVMCG with dark matter with the best fitted value of the parameters and comparing with that derived from the union2 compilation data.

Jhumpa Bhadra; Ujjal Debnath

2012-11-09T23:59:59.000Z

252

Electrical Transport Experiments at High Pressure  

Science Conference Proceedings (OSTI)

High-pressure electrical measurements have a long history of use in the study of materials under ultra-high pressures. In recent years, electrical transport experiments have played a key role in the study of many interesting high pressure phenomena including pressure-induced superconductivity, insulator-to-metal transitions, and quantum critical behavior. High-pressure electrical transport experiments also play an important function in geophysics and the study of the Earth's interior. Besides electrical conductivity measurements, electrical transport experiments also encompass techniques for the study of the optoelectronic and thermoelectric properties of materials under high pressures. In addition, electrical transport techniques, i.e., the ability to extend electrically conductive wires from outside instrumentation into the high pressure sample chamber have been utilized to perform other types of experiments as well, such as high-pressure magnetic susceptibility and de Haas-van Alphen Fermi surface experiments. Finally, electrical transport techniques have also been utilized for delivering significant amounts of electrical power to high pressure samples, for the purpose of performing high-pressure and -temperature experiments. Thus, not only do high-pressure electrical transport experiments provide much interesting and valuable data on the physical properties of materials extreme compression, but the underlying high-pressure electrical transport techniques can be used in a number of ways to develop additional diagnostic techniques and to advance high pressure capabilities.

Weir, S

2009-02-11T23:59:59.000Z

253

Grassmann Variables in Jordan Matrix Models  

E-Print Network (OSTI)

Here we demonstrate the emergence of Grassmann variables in matrix models based on the exceptional Jordan algebra. The Grassmann algebras are built naturally using the octonion algebra. We argue the appearance of Grassmann variables solidifies the relationship between supersymmetry and triality.

Michael Rios

2005-03-02T23:59:59.000Z

254

THE MULTI-USE STEINEL VARIABLE TEMPERATURE  

E-Print Network (OSTI)

THE MULTI-USE STEINEL VARIABLE TEMPERATURE ELECTRONICALLY CONTROLLED HEAT GUNTEMPERATURE RANGE 212 COMBUSTIBLE LIQUIDS. DO NOT USE FOR: · Heating gas engines · Heating car batteries · Thawing refrigerator equipment Specifications Temperature Variable from 212° F to 1100° F Watts 1500W Weight 1.5 lbs. Supply

Kleinfeld, David

255

THE MULTI-USE STEINEL VARIABLE TEMPERATURE  

E-Print Network (OSTI)

THE MULTI-USE STEINEL VARIABLE TEMPERATURE ELECTRONICALLY CONTROLLED HEAT GUNTEMPERATURE RANGE 212 COMBUSTIBLE LIQUIDS. DO NOT USE FOR: · Heating gas engines · Heating car batteries · Thawing refrigerator equipment Specifications Temperature Variable from 212" F to 1100° F Watts 1500W Weight 1.5 lbs. Supply

Kleinfeld, David

256

Internal Variability of Indian Ocean SST  

Science Conference Proceedings (OSTI)

A 40-yr integration of an eddy-resolving numerical model of the tropical Indian Ocean is analyzed to quantify the interannual variability that is caused by the internal variability of ocean dynamics. It is found that along the equator in the ...

Markus Jochum; Raghu Murtugudde

2005-09-01T23:59:59.000Z

257

Gradient based variable forgetting factor RLS algorithm  

Science Conference Proceedings (OSTI)

An accurate new variable forgetting factor recursive least-square adaptive algorithm is derived. An improved mean square behaviour analysis is presented, which shows that the theoretical analysis and the simulation results are close to each other. The ... Keywords: RLS algorithm, adaptive filters, variable forgetting factor

C. F. So; S. C. Ng; S. H. Leung

2003-06-01T23:59:59.000Z

258

Variable orifice using an iris shutter  

DOE Patents (OSTI)

A variable orifice forming mechanism utilizing an iris shutter arrangement adapted to control gas flow, conductance in vacuum systems, as a heat shield for furnace windows, as a beam shutter in sputtering operations, and in any other application requiring periodic or continuously-variable control of material, gas, or fluid flow.

Beeman, Raymond (El Cerrito, CA); Brajkovich, Steven J. (Fremont, CA)

1978-01-01T23:59:59.000Z

259

Bond Graph Modeling Of Variable Structure Systems  

E-Print Network (OSTI)

The problem of describing variable structure models in a compact, object--oriented fashion is revisited and analyzed from the perspective of bond graph modeling. Traditionally, bond graphs have always been used to describe continuous-- time physical processes with a fixed structure. Yet, this paper shall demonstrate that bond graphs are equally suitable to describe variable structure models as fixed structure models. Moreover, a bond graph description of variable structure models can teach us a lot about the essential properties of variable structure models, properties that are not easily visible when other modeling approaches are taken. The paper discusses issues related to causality reassignment and conditional index changes as a consequence of switching in a physical system. Keywords: Bond graphs, variable structure system, computational causality, conditional index change, switching, object--oriented modeling, Dymola. INTRODUCTION When the causality strokes were added to the forme...

François E. Cellier; Martin Otter; Hilding Elmqvist

1995-01-01T23:59:59.000Z

260

PRESSURE VESSEL FABRICATION USING T-1 STEEL  

SciTech Connect

The fabrication of pressure vessels using C-l steel is described. The welding, welding electrodes, explosionbulge test, and impact and fatigue properties for the pressure vessel are given. (W.L.H.)

Franco-Ferreira, E.A.

1957-11-14T23:59:59.000Z

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


261

Pressure Compensation and the Bottom Boundary Layer  

Science Conference Proceedings (OSTI)

It is an observed characteristic of oceans that velocities and horizontal pressure gradients are larger new the ocean surface than they are in deeper water. This is conventionally labeled “pressure compensation” whereby baroclinic structure, ...

George L. Mellor; Xiao Hua Wang

1996-10-01T23:59:59.000Z

262

Energy Basics: Low-Pressure Sodium Lighting  

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

Low-Pressure Sodium Lighting Low-pressure sodium lighting provides more energy-efficient outdoor lighting than high-intensity discharge lighting, but it has very poor color...

263

Carbon nanotube temperature and pressure sensors  

Science Conference Proceedings (OSTI)

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.

Ivanov, Ilia N; Geohegan, David Bruce

2013-10-29T23:59:59.000Z

264

Autogenic Pressure Reactions for Battery Materials Manufacture...  

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

Autogenic Pressure Reactions for Battery Materials Manufacture Technology available for licensing: A unique method for anode and cathode manufacture autogenicpressurereactions...

265

LOW PRESSURE CHEMICAL VAPOR DEPOSITION OF POLYSILICON  

E-Print Network (OSTI)

THEORY The mass transport processes in low pressure chemical vapor deposition (LPCVD) are similar to those occuring in catalytic reactors

Gieske, R.J.

2011-01-01T23:59:59.000Z

266

WH[eta] under pressure  

SciTech Connect

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.

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

2012-05-10T23:59:59.000Z

267

Measurement of specimen dimensions and dynamic pressure in dynamic triaxial experiments  

SciTech Connect

Novel experimental techniques are developed to measure the rapid changes in specimen dimensions during dynamic triaxial experiments. A capacitance gage is designed and constructed to measure the diameter change of the specimen inside the pressure chamber at both low and high rates. The length change is determined by a linear variable differential transformer at low rates and by Kolsky bar signals at high rates. The Kolsky bar also measures the dynamic axial stress in the specimen during the high-rate phase of an experiment. A line pressure gage records the hydrostatic pressure in the chamber. The dynamic pressure variation in the chamber during axial impact loading is detected by a manganin gage placed inside the chamber. The feasibility of this new experimental setup is demonstrated by dynamic triaxial experiments on a fine dry sand.

Kabir, Md. E. [School of Aeronautics/Astronautics, Purdue University, 701 West Stadium Avenue, West Lafayette, Indiana 47907-2045 (United States); Chen, Weinong W. [School of Aeronautics/Astronautics, Purdue University, 701 West Stadium Avenue, West Lafayette, Indiana 47907-2045 (United States); School of Materials Engineering, Purdue University, 701 West Stadium Avenue, West Lafayette, Indiana 47907-2045 (United States)

2009-12-15T23:59:59.000Z

268

Electokinetic high pressure hydraulic system  

DOE Patents (OSTI)

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.

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

2000-01-01T23:59:59.000Z

269

Reactor pressure vessel vented head  

DOE Patents (OSTI)

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.

Sawabe, James K. (San Jose, CA)

1994-01-11T23:59:59.000Z

270

Effects of Pressure on Oxygen Sensors  

Science Conference Proceedings (OSTI)

To measure the effects of pressure on the output of a membrane oxygen sensor and a nonmembrane oxygen sensor, the authors pressure cycled a CTD sensor package in a laboratory pressure facility. The CTD sensor package was cycled from 30 to 6800 db ...

M. J. Atkinson; F. I. M. Thomas; N. Larson

1996-12-01T23:59:59.000Z

271

High-pressure microhydraulic actuator  

DOE Patents (OSTI)

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.

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

2008-06-10T23:59:59.000Z

272

Pressurized solid oxide fuel cell testing  

DOE Green Energy (OSTI)

The Pressurized SOFC Test Program is an integral part of the Cooperative Agreement between Westinghouse and DOE and was put into place to evaluate the effects of pressurization on SOFC performance. The goals of the SOFC pressurized test program are to obtain cell voltage versus current (VI) performance data as a function of pressure; to evaluate the effects of operating parameters such as temperature, air stoichiometry, and fuel utilization on cell performance, and to demonstrate long term stability of the SOFC materials at elevated pressures.

Ray, E.R.; Basel, R.A.; Pierre, J.F.

1995-12-31T23:59:59.000Z

273

Pressure transient method for front tracking  

DOE Green Energy (OSTI)

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.

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

1983-08-01T23:59:59.000Z

274

Low frequency pressure modulation of indium antimonide  

Science Conference Proceedings (OSTI)

A lumped parameter resonator capable of generating megapascal pressures at low frequency (kilohertz) is described. Accelerometers are used to determine the applied pressure, and are calibrated with a piezoelectric sample. A laser diagnostic was also developed to measure the pressure in semiconductor samples through the band gap pressure dependence. In addition, the laser diagnostic has been used to measure the attenuation coefficient {alpha} of commercially available indium antimonide (InSb) wafers. The resonator and laser diagnostic have been used with InSb samples to verify the pressure response.

Hallock, Gary A. [University of Texas at Austin, Austin, Texas 78712-0240 (United States); Meier, Mark A. [ExxonMobil Upstream Research Company, Houston, Texas 77252-2189 (United States)

2012-07-15T23:59:59.000Z

275

Richtmyer-Meshkov Instability of a Liquid-Gas Interface Driven by a Cylindrical Imploding Pressure Wave  

E-Print Network (OSTI)

The compression of a cylindrical gas bubble by an imploding molten lead (Pb) shell may be accompanied by the development of the Richtmyer-Meshkov (RM) instability at the liquid-gas interface due to the initial imperfection of the interface. A converging pressure wave impinging upon the interface causes a shell of liquid to detach and continue to travel inwards, compressing the gas bubble. The efficiency of compression and collapse evolution can be affected by development of the RM instability. Investigations have been performed in the regime of extreme Atwood number $A=-1$ with the additional complexity of modeling liquid cavitation in the working fluid. Simulations have been carried out using the open source CFD software OpenFOAM on a set of parameters relevant to the prototype compression system under development at General Fusion Inc. for use as a Magnetized Target Fusion (MTF) driver. After validating the numerical setup in planar geometry, simulations have been carried out in 2D cylindrical geometry for both initially smooth and perturbed interfaces. Where possible, results have been validated against existing theoretical models and very good agreement has been found. While our main focus is on the effects of initial perturbation amplitude and azimuthal mode number, we also address differences between this problem and those usually considered, such as RM instability at an interface between two gases with a moderate density ratio. One important difference is the formation of narrow molten lead jets rapidly propagating inwards during the final stages of the collapse. Jet behaviour has been observed for a range of azimuthal mode numbers and perturbation amplitudes.

Victoria Suponitsky; Sandra Barsky; Aaron Froese

2013-10-22T23:59:59.000Z

276

Nine New Variable Stars in Camelopardalis  

E-Print Network (OSTI)

Nine new short period variable stars have been discovered in the direction of the open cluster Cr464 in Camelopardalis. The field was observed using Tzec Maun Observatory's telescope AP180. Two new variable stars were classified as pulsating stars (RRab and RRc types). The other seven stars are binary systems. One of them is of ELL-type, four binaries were recognized as EW-type, and two systems are rather short period EA-type binaries. All new variables were registered in the VSX catalogue.

Virnina, Natalia A

2013-01-01T23:59:59.000Z

277

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

DOE Patents (OSTI)

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.

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

2000-01-01T23:59:59.000Z

278

Air flow and pressure inside a pressure-swirl spray and their effects on spray development  

SciTech Connect

Air flow and pressure inside a pressure-swirl spray for direct injection (DI) gasoline engines and their effects on spray development have been analyzed at different injector operating conditions. A simulation tool was utilized and the static air pressure at the centerline of the spray was measured to investigate the static pressure and flow structure inside the swirl spray. To investigate the effect of static air pressure on swirl spray development, a liquid film model was applied and the Mie-scattered images were captured. The simulation and experiment showed that recirculation vortex and air pressure drop inside the swirl spray were observable and the air pressure drop was greater at high injection pressure. At high fuel temperature, the air pressure at the nozzle exit showed higher value compared to the atmospheric pressure and then continuously decreased up to few millimeters distance from the nozzle exit. The pressure drop at high fuel temperatures was more than that of atmospheric temperature. This reduced air pressure was recovered to the atmospheric pressure at further downstream. The results from the liquid film model and macroscopic spray images showed that the air pressure started to affect the liquid film trajectory about 3 mm from the nozzle exit and this effect was sustained until the air pressure recovered to the atmospheric pressure. However, the entrained air motion and droplet size have more significant influence on the spray development after the most of the liquid sheet is broken-up and the spray loses its initial momentum. (author)

Moon, Seoksu; Bae, Choongsik [Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Guseong-dong, Yuseong-gu, Daejon 305-701 (Korea); Abo-Serie, Essam [Department of Mechanical Engineering and Design, Coventry University, Priory Street, Coventry CV1 5FB (United Kingdom)

2009-01-15T23:59:59.000Z

279

AUTOMATIC CALIBRATING SYSTEM FOR PRESSURE TRANSDUCERS  

DOE Patents (OSTI)

An automatic system for calibrating a number of pressure transducers is described. The disclosed embodiment of the invention uses a mercurial manometer to measure the air pressure applied to the transducer. A servo system follows the top of the mercury column as the pressure is changed and operates an analog- to-digital converter This converter furnishes electrical pulses, each representing an increment of pressure change, to a reversible counterThe transducer furnishes a signal at each calibration point, causing an electric typewriter and a card-punch machine to record the pressure at the instant as indicated by the counter. Another counter keeps track of the calibration points so that a number identifying each point is recorded with the corresponding pressure. A special relay control system controls the pressure trend and programs the sequential calibration of several transducers.

Amonette, E.L.; Rodgers, G.W.

1958-01-01T23:59:59.000Z

280

Passive tire pressure sensor and method  

Science Conference Proceedings (OSTI)

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.

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

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


281

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

DOE Green Energy (OSTI)

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.

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

1984-06-01T23:59:59.000Z

282

Property:Real-Time | Open Energy Information  

Open Energy Info (EERE)

Real-Time Real-Time Jump to: navigation, search Property Name Real-Time Property Type String Pages using the property "Real-Time" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + No + 10-ft Wave Flume Facility + No + 11-ft Wave Flume Facility + No + 2 2-ft Flume Facility + No + 3 3-ft Wave Flume Facility + No + 5 5-ft Wave Flume Facility + No + 6 6-ft Wave Flume Facility + No + A Alden Large Flume + Yes + Alden Small Flume + Yes + Alden Tow Tank + Yes + Alden Wave Basin + Yes + B Breakwater Research Facility + No + Bucknell Hydraulic Flume + No + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + No + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + No + Carderock Circulating Water Channel + No +

283

Category:Testing Facilities | Open Energy Information  

Open Energy Info (EERE)

Facilities Facilities Jump to: navigation, search This category is defined by the form Testing Facility. Subcategories This category has only the following subcategory. H [×] Hydrodynamic Testing Facility Type‎ 9 pages Pages in category "Testing Facilities" The following 82 pages are in this category, out of 82 total. 1 1.5-ft Wave Flume Facility 10-ft Wave Flume Facility 11-ft Wave Flume Facility 2 2-ft Flume Facility 3 3-ft Wave Flume Facility 5 5-ft Wave Flume Facility 6 6-ft Wave Flume Facility A Alden Large Flume Alden Small Flume Alden Tow Tank Alden Wave Basin B Breakwater Research Facility Bucknell Hydraulic Flume C Carderock 2-ft Variable Pressure Cavitation Water Tunnel Carderock 3-ft Variable Pressure Cavitation Water Tunnel Carderock Circulating Water Channel

284

Property:Cameras | Open Energy Information  

Open Energy Info (EERE)

Property Property Edit with form History Facebook icon Twitter icon » Property:Cameras Jump to: navigation, search Property Name Cameras Property Type Text Pages using the property "Cameras" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + None 10-ft Wave Flume Facility + None 11-ft Wave Flume Facility + None 2 2-ft Flume Facility + None 3 3-ft Wave Flume Facility + None 5 5-ft Wave Flume Facility + None 6 6-ft Wave Flume Facility + None A Alden Large Flume + Yes Alden Small Flume + Yes Alden Tow Tank + Yes Alden Wave Basin + Yes B Breakwater Research Facility + None C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + None Carderock 3-ft Variable Pressure Cavitation Water Tunnel + None Carderock Circulating Water Channel + None

285

Property:Wavemaking Capabilities | Open Energy Information  

Open Energy Info (EERE)

Wavemaking Capabilities Wavemaking Capabilities Jump to: navigation, search Property Name Wavemaking Capabilities Property Type String Pages using the property "Wavemaking Capabilities" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + Yes + 10-ft Wave Flume Facility + Yes + 11-ft Wave Flume Facility + Yes + 2 2-ft Flume Facility + Yes + 3 3-ft Wave Flume Facility + Yes + 5 5-ft Wave Flume Facility + Yes + 6 6-ft Wave Flume Facility + Yes + A Alden Large Flume + Yes + Alden Small Flume + Yes + Alden Tow Tank + None + Alden Wave Basin + Yes + B Breakwater Research Facility + Yes + Bucknell Hydraulic Flume + None + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + None + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + None +

286

Property:Wind Capabilities | Open Energy Information  

Open Energy Info (EERE)

Capabilities Capabilities Jump to: navigation, search Property Name Wind Capabilities Property Type String Pages using the property "Wind Capabilities" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + None + 10-ft Wave Flume Facility + None + 11-ft Wave Flume Facility + Yes + 2 2-ft Flume Facility + None + 3 3-ft Wave Flume Facility + None + 5 5-ft Wave Flume Facility + None + 6 6-ft Wave Flume Facility + None + A Alden Large Flume + Yes + Alden Small Flume + Yes + Alden Tow Tank + Yes + Alden Wave Basin + Yes + B Breakwater Research Facility + None + Bucknell Hydraulic Flume + None + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + None + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + None +

287

Property:Towing Capabilities | Open Energy Information  

Open Energy Info (EERE)

Towing Capabilities Towing Capabilities Jump to: navigation, search Property Name Towing Capabilities Property Type String Pages using the property "Towing Capabilities" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + None + 10-ft Wave Flume Facility + None + 11-ft Wave Flume Facility + None + 2 2-ft Flume Facility + None + 3 3-ft Wave Flume Facility + None + 5 5-ft Wave Flume Facility + None + 6 6-ft Wave Flume Facility + None + A Alden Large Flume + Yes + Alden Small Flume + None + Alden Tow Tank + Yes + Alden Wave Basin + None + B Breakwater Research Facility + None + Bucknell Hydraulic Flume + Yes + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + None + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + None +

288

Property:Test Services | Open Energy Information  

Open Energy Info (EERE)

Services Services Jump to: navigation, search Property Name Test Services Property Type String Pages using the property "Test Services" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + Yes + 10-ft Wave Flume Facility + Yes + 11-ft Wave Flume Facility + Yes + 2 2-ft Flume Facility + Yes + 3 3-ft Wave Flume Facility + Yes + 5 5-ft Wave Flume Facility + Yes + 6 6-ft Wave Flume Facility + Yes + A Alden Large Flume + Yes + Alden Small Flume + Yes + Alden Tow Tank + Yes + Alden Wave Basin + Yes + B Breakwater Research Facility + None + Bucknell Hydraulic Flume + Yes + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + None + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + None + Carderock Circulating Water Channel + None +

289

Property:Channel/Tunnel/Flume | Open Energy Information  

Open Energy Info (EERE)

Channel/Tunnel/Flume Channel/Tunnel/Flume Jump to: navigation, search Property Name Channel/Tunnel/Flume Property Type String Pages using the property "Channel/Tunnel/Flume" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + Yes + 10-ft Wave Flume Facility + Yes + 11-ft Wave Flume Facility + None + 2 2-ft Flume Facility + Yes + 3 3-ft Wave Flume Facility + None + 5 5-ft Wave Flume Facility + Yes + 6 6-ft Wave Flume Facility + Yes + A Alden Large Flume + Yes + Alden Small Flume + Yes + Alden Tow Tank + None + Alden Wave Basin + None + B Breakwater Research Facility + None + Bucknell Hydraulic Flume + Yes + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + Yes + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + Yes +

290

Property:Special Characteristics | Open Energy Information  

Open Energy Info (EERE)

Characteristics Characteristics Jump to: navigation, search Property Name Special Characteristics Property Type String Pages using the property "Special Characteristics" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + None + 10-ft Wave Flume Facility + None + 11-ft Wave Flume Facility + Yes + 2 2-ft Flume Facility + None + 3 3-ft Wave Flume Facility + None + 5 5-ft Wave Flume Facility + None + 6 6-ft Wave Flume Facility + Yes + A Alden Large Flume + Yes + Alden Small Flume + Yes + Alden Tow Tank + None + Alden Wave Basin + Yes + B Breakwater Research Facility + None + Bucknell Hydraulic Flume + Yes + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + None + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + None +

291

Variability of EGRET Gamma-Ray Sources  

E-Print Network (OSTI)

The variability of the high-energy gamma ray sources in the Third EGRET catalog is analyzed by a new method. We re-analyze the EGRET data to calculate a likelihood function for the flux of each source in each observation, both for detections and upper limits. These functions can be combined in a uniform manner with a simple model of the flux distribution to characterize the flux variation by a confidence interval for the relative standard deviation of the flux. The main result is a table of these values for almost all the cataloged sources. As expected, the identified pulsars are steady emitters and the blazars are mostly highly variable. The unidentified sources are heterogeneous, with greater variation at higher Galactic latitude. There is an indication that pulsar wind nebulae are associated with variable sources. There is a population of variable sources along the Galactic plane, concentrated in the inner spiral arms.

P. L. Nolan; W. F. Tompkins; I. A. Grenier; P. F. Michelson

2003-07-10T23:59:59.000Z

292

Interannual Variability of Northwest Australian Tropical Cyclones  

Science Conference Proceedings (OSTI)

Tropical cyclone (TC) activity over the southeast Indian Ocean has been studied far less than other TC basins, such as the North Atlantic and northwest Pacific. The authors examine the interannual TC variability of the northwest Australian (NWAUS)...

Kevin H. Goebbert; Lance M. Leslie

2010-09-01T23:59:59.000Z

293

Variability of Southern Ocean Jets Near Topography  

Science Conference Proceedings (OSTI)

The interaction of jets with topography in the Southern Ocean is investigated using 19 years of altimetry data. In particular, the “jet jumping” mode of variability, by which two or more jets passing close to the same topographic feature show ...

Christopher C. Chapman; Rosemary Morrow

294

Weather Noise Forcing of Surface Climate Variability  

Science Conference Proceedings (OSTI)

A model-based method to evaluate the role of weather noise forcing of low-frequency variability of surface properties, including SST, surface currents, land surface temperature, and soil moisture, is presented. In this procedure, an “interactive ...

Edwin K. Schneider; Meizhu Fan

2007-09-01T23:59:59.000Z

295

Experiments Concerning Variability among Subjective Analyses  

Science Conference Proceedings (OSTI)

The variability of subjective (hand) analyses is explored by examining the results of two synoptic laboratory experiments. Two groups of analysts participated in the first experiment, one consisting of 13 senior meteorology students (1977), the ...

Dayton G. Vincent; Herbert Borenstein

1980-10-01T23:59:59.000Z

296

Tropical Convective Variability as 1/f Noise  

Science Conference Proceedings (OSTI)

Evidence is presented that the tropical convective variability behaves as 1/f noise for a 1–30-day period. This behavior is shown by analyzing the time series of convective available potential energy, which measures the degree of convective ...

Jun-Ichi Yano; Klaus Fraedrich; Richard Blender

2001-09-01T23:59:59.000Z

297

Optimizing Crop Insurance under Climate Variability  

Science Conference Proceedings (OSTI)

This paper studies the selection of optimal crop insurance under climate variability and fluctuating market prices. A model was designed to minimize farmers’ expected losses (including insurance costs) while using the conditional-value-at-risk ...

Juan Liu; Chunhua Men; Victor E. Cabrera; Stan Uryasev; Clyde W. Fraisse

2008-10-01T23:59:59.000Z

298

Variable volume architecture : expanding the boundary  

E-Print Network (OSTI)

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. ...

Saheba, Asheshh (Asheshh Mohit), 1972-

2001-01-01T23:59:59.000Z

299

Backscatter Differential Phase—Estimation and Variability  

Science Conference Proceedings (OSTI)

On the basis of simulations and observations made with polarimetric radars operating at X, C, and S bands, the backscatter differential phase ? has been explored; ? has been identified as an important polarimetric variable that should not be ...

Silke Trömel; Matthew R. Kumjian; Alexander V. Ryzhkov; Clemens Simmer; Malte Diederich

2013-11-01T23:59:59.000Z

300

Spatial Variability of Outgoing Longwave Radiation  

Science Conference Proceedings (OSTI)

Data from the Earth Radiation Budget Experiment scanning radiometer aboard the NOAA-9 operational meteorological satellite are used to investigate the spatial variability of outgoing longwave radiation (OLR). Daily and monthly radiation maps at ...

G. Louis Smith; David Rutan

1994-07-01T23:59:59.000Z

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


301

Climate Variability and Sugarcane Yield in Louisiana  

Science Conference Proceedings (OSTI)

This paper seeks to understand the role that climate variability has on annual yield of sugarcane in Louisiana. Unique features of sugarcane growth in Louisiana and nonclimatic, yield-influencing factors make this goal an interesting and ...

David Greenland

2005-11-01T23:59:59.000Z

302

Integrating Variable Renewable Energy: Challenges and Solutions  

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

LLC This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.govpublications. Contract No. DE-AC36-08GO28308 Integrating Variable...

303

High Pressure Hydrogen Tank Manufacturing  

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

Workshop Workshop High Pressure Hydrogen Tank Manufacturing Mark Leavitt Quantum Fuel Systems Technologies Worldwide, Inc. August 11, 2011 This presentation does not contain any proprietary, confidential, or otherwise restricted information History of Innovations... Announced breakthrough in all-composite lightweight, high capacity, low-cost fuel storage technologies. * Developed a series of robust, OEM compatible electronic control products. Developed H 2 storage system for SunLine Tran-sit Hythane® bus. Awarded patent for integrated module including in-tank regulator * Developed high efficiency H 2 fuel storage systems for DOE Future Truck programs Developed H 2 storage and metering system for Toyota's FCEV platform. First to certify 10,000 psi systems in Japan

304

Low-pressure ion source  

DOE Patents (OSTI)

A low pressure ion source for a neutron source comprises a filament cathode and an anode ring. Approximately 150V is applied between the cathode and the anode. Other electrodes, including a heat shield, a reflector and an aperture plate with a focus electrode, are placed at intermediate potentials. Electrons from the filament drawn out by the plasma and eventually removed by the anode are contained in a magnetic field created by a magnet ring. Ions are formed by electron impact with deuterium or tritium and are extracted at the aperture in the focus electrode. The ion source will typically generate a 200 mA beam through a 1.25 cm/sup 2/ aperture for an arc current of 10A. For deuterium gas, the ion beam is over 50 percent D/sup +/ with less than 1% impurity. The current density profile across the aperture will typically be uniform to within 20%.

Bacon, F.M.; Brainard, J.P.; O' Hagan, J.B.; Walko, R.J.

1982-10-27T23:59:59.000Z

305

Reactor pressure vessel vented head  

DOE Patents (OSTI)

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.

Sawabe, J.K.

1994-01-11T23:59:59.000Z

306

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

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

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....

307

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

SciTech Connect

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.

Khan, M. Rashid (Morgantown, WV)

1990-01-01T23:59:59.000Z

308

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

DOE Patents (OSTI)

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. 7 figs.

Khan, M.R.

1989-05-12T23:59:59.000Z

309

High Pressure Rotary Shaft Sealing Mechanism  

DOE Patents (OSTI)

A laterally translatable pressure staged rotary shaft sealing mechanism having a seal housing with a shaft passage therein being exposed to a fluid pressure P1 and with a rotary shaft being located within the shaft passage. At least one annular laterally translatable seal carrier is provided. First and second annular resilient sealing elements are supported in axially spaced relation by the annular seal carriers and have sealing relation with the rotary shaft. The seal housing and at least one seal carrier define a first pressure staging chamber exposed to the first annular resilient sealing element and a second pressure staging chamber located between and exposed to the first and second annular resilient sealing elements. A first fluid is circulated to the first pressure chamber at a pressure P1, and a second staging pressure fluid is circulated to the second pressure chamber at a fraction of pressure P1 to achieve pressure staging, cooling of the seals. Seal placement provides hydraulic force balancing of the annular seal carriers.

Dietle, Lannie (Sugar Land, TX); Gobeli, Jeffrey D. (Houston, TX)

2001-05-08T23:59:59.000Z

310

Dirac equation in terms of hydrodynamic variables  

E-Print Network (OSTI)

The distributed system $\\mathcal{S}_D$ described by the Dirac equation is investigated simply as a dynamic system, i.e. without usage of quantum principles. The Dirac equation is described in terms of hydrodynamic variables: 4-flux $j^{i}$, pseudo-vector of the spin $S^{i}$, an action $\\hbar \\phi $ and a pseudo-scalar $\\kappa $. In the quasi-uniform approximation, when all transversal derivatives (orthogonal to the flux vector $j^i$) are small, the system $\\mathcal{S}_D$ turns to a statistical ensemble of classical concentrated systems $\\mathcal{S}_{dc}$. Under some conditions the classical system $\\mathcal{S}_{dc}$ describes a classical pointlike particle moving in a given electromagnetic field. In general, the world line of the particle is a helix, even if the electromagnetic field is absent. Both dynamic systems $\\mathcal{S}_D$ and $\\mathcal{S}_{dc}$ appear to be non-relativistic in the sense that the dynamic equations written in terms of hydrodynamic variables are not relativistically covariant with respect to them, although all dynamic variables are tensors or pseudo-tensors. They becomes relativistically covariant only after addition of a constant unit timelike vector $f^{i}$ which should be considered as a dynamic variable describing a space-time property. This "constant" variable arises instead of $\\gamma $-matrices which are removed by means of zero divizors in the course of the transformation to hydrodynamic variables. It is possible to separate out dynamic variables $\\kappa $, $\\kappa ^i$ responsible for quantum effects. It means that, setting $\\kappa ,\\kappa ^i\\equiv 0$, the dynamic system $\\mathcal{S}_D$ described by the Dirac equation turns to a statistical ensemble $\\mathcal{E}_{Dqu}$ of classical dynamic systems $\\mathcal{S}_{dc}$.

Yuri A. Rylov

2011-01-31T23:59:59.000Z

311

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

SciTech Connect

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.

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

1995-11-01T23:59:59.000Z

312

Portable high precision pressure transducer system  

DOE Patents (OSTI)

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.

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

1994-04-26T23:59:59.000Z

313

Portable high precision pressure transducer system  

DOE Patents (OSTI)

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.

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

1992-12-31T23:59:59.000Z

314

Portable high precision pressure transducer system  

SciTech Connect

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.

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

315

Multicomponent fuel vaporization at high pressures.  

DOE Green Energy (OSTI)

We extend our multicomponent fuel model to high pressures using a Peng-Robinson equation of state, and implement the model into KIVA-3V. Phase equilibrium is achieved by equating liquid and vapor fugacities. The latent heat of vaporization and fuel enthalpies are also corrected for at high pressures. Numerical simulations of multicomponent evaporation are performed for single droplets for a diesel fuel surrogate at different pressures.

Torres, D. J. (David J.); O'Rourke, P. J. (Peter J.)

2002-01-01T23:59:59.000Z

316

Embrittlement of Nuclear Reactor Pressure Vessels  

Science Conference Proceedings (OSTI)

Boiler and Pressure Vessel Code Section III App. G Protection Against Nonductile Fracture (New York: American Society of Mechanical Engineers, 1986 ). 3.

317

Carbon Nanotubes Make Simultaneous Temperature, Pressure ...  

ORNL 2010-G00384/jcn UT-B ID 200702020 Carbon Nanotubes Make Simultaneous Temperature, Pressure Sensors Possible Technology Summary Carbon nanotubes ...

318

Pressure and Vacuum Group International Comparisons  

Science Conference Proceedings (OSTI)

... Vacuum. 2010 Olson DA, Abbott PJ, Jousten K, Redgrave FJ, Mohan P, Hong SS, Final report of key comparison CCM.P-K3 absolute pressure ...

2012-10-02T23:59:59.000Z

319

Conceptual Design for Pressure Swing Distillation.  

E-Print Network (OSTI)

??The separation of homogenous azeotropic mixtures is a common task in the chemical industry. In the literature, pressure swing distillation is often mentioned as an… (more)

Bozzacco, Carmen

2006-01-01T23:59:59.000Z

320

Electron reactions in nonpolar liquids: Pressure effects  

SciTech Connect

Theory predicts that electron energy levels in nonpolar molecular hydrocarbons should increase in energy with density/pressure increase, and therefore electron attachment rates in solution should change with pressure. Studies of pressure effect on electron mobility show that some contraction occurs around trapped electrons, but more contraction occurs around ions in hydrocarbons. After a brief discussion of pressure effects on electron energy levels and mobility, this paper reports studies of electron attachment reactions of N{sub 2}O, CO{sub 2}, and n-C{sub 5}F{sub 12} in tetramethylsilane, and of toluene, benzene, CO{sub 2}, and 1,3-butadiene in several solvents.

Holroyd, R.A.

1993-09-01T23:59:59.000Z

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


321

Lightweight bladder lined pressure vessels  

DOE Patents (OSTI)

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.

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

1998-08-25T23:59:59.000Z

322

Lightweight bladder lined pressure vessels  

DOE Patents (OSTI)

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.

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

323

Apparatus for unloading pressurized fluid  

DOE Patents (OSTI)

An apparatus is described for unloading fluid, preferably pressurized gas, from containers in a controlled manner that protects the immediate area from exposure to the container contents. The device consists of an unloading housing, which is enclosed within at least one protective structure, for receiving the dispensed contents of the steel container, and a laser light source, located external to the protective structure, for opening the steel container instantaneously. The neck or stem of the fluid container is placed within the sealed interior environment of the unloading housing. The laser light passes through both the protective structure and the unloading housing to instantaneously pierce a small hole within the stem of the container. Both the protective structure and the unloading housing are specially designed to allow laser light passage without compromising the light's energy level. Also, the unloading housing allows controlled flow of the gas once it has been dispensed from the container. The external light source permits remote operation of the unloading device. 2 figures.

Rehberger, K.M.

1994-01-04T23:59:59.000Z

324

Pressurized fluidized-bed combustion  

Science Conference Proceedings (OSTI)

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)

Not Available

1980-10-01T23:59:59.000Z

325

The gravitational energy-momentum tensor and the gravitational pressure  

E-Print Network (OSTI)

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.

J. W. Maluf

2005-04-18T23:59:59.000Z

326

Variables et categories grammaticales dans un modele ariane  

Science Conference Proceedings (OSTI)

Toutes tes catégories grammaticales utilisées dans un modéle de traduction ariane sont formalisées et codées de faç mnémonique en tant que variables et valeurs de variables. L'ensemble des variables d'un ...

Jean-Phillippe Guilbaud

1986-08-01T23:59:59.000Z

327

Reversible Record Breaking and Variability: Temperature Distributions across the Globe  

Science Conference Proceedings (OSTI)

Based on counts of record highs and lows, and employing reversibility in time, an approach to examining natural variability is proposed. The focus is on intrinsic variability; that is, variance separated from the trend in the mean. A variability ...

Amalia Anderson; Alexander Kostinski

2010-08-01T23:59:59.000Z

328

U.S. Economic Sensitivity to Weather Variability  

Science Conference Proceedings (OSTI)

To estimate the economic effects of weather variability in the United States, the authors define and measure weather sensitivity as the variability in economic output that is attributable to weather variability, accounting for changes in technology and ...

Jeffrey K. Lazo; Megan Lawson; Peter H. Larsen; Donald M. Waldman

2011-06-01T23:59:59.000Z

329

Integrating Variable Renewable Energy: Challenges and Solutions  

SciTech Connect

In the U.S., a number of utilities are adopting higher penetrations of renewables, driven in part by state policies. While power systems have been designed to handle the variable nature of loads, the additional supply-side variability and uncertainty can pose new challenges for utilities and system operators. However, a variety of operational and technical solutions exist to help integrate higher penetrations of wind and solar generation. This paper explores renewable energy integration challenges and mitigation strategies that have been implemented in the U.S. and internationally, including forecasting, demand response, flexible generation, larger balancing areas or balancing area cooperation, and operational practices such as fast scheduling and dispatch.

Bird, L.; Milligan, M.; Lew, D.

2013-09-01T23:59:59.000Z

330

Synthetic Subsurface Pressure Derived from Bottom Pressure and Tide Gauge Observations  

Science Conference Proceedings (OSTI)

Synthetic subsurface pressure (SSP) can be formed from tide gauge records and from bottom pressure measurements to provide a consistent and convenient basis for comparison of these two different types of observations. Common methods for this ...

Sabine Harms; Clinton D. Winant

1994-12-01T23:59:59.000Z

331

Adaptive variable structure control law for a variable speed wind turbine  

Science Conference Proceedings (OSTI)

The efficiency of the wind power conversions systems can be greatly improved using an appropriate control algorithm. In this work, an adaptive robust control for a doubly feed induction generator drive for variable speed wind power generation is described. ... Keywords: modeling and simulation, variable structure control, wind turbine control

Oscar Barambones; Jose Maria Gonzalez De Durana; Patxi Alkorta; Jose Antonio Ramos; Manuel De La Sen

2011-05-01T23:59:59.000Z

332

Flight Control Design for Rotorcraft with Variable Rotor Speed.  

E-Print Network (OSTI)

??Flight control design issues for rotorcraft with variable rotor speed are investigated, and new design methodologies are developed to deal with the challenges of variable… (more)

Guo, Wei

2009-01-01T23:59:59.000Z

333

Adaptation to Climate Variability and Change: A Guidance Manual...  

Open Energy Info (EERE)

Adaptation to Climate Variability and Change: A Guidance Manual for Development Planning Jump to: navigation, search Tool Summary Name: Adaptation to Climate Variability and...

334

2005 RECS Variable Response Code Labels - U.S. Energy ...  

U.S. Energy Information Administration (EIA)

7 concrete or concrete block 8 glass 9 other 10 indescribable : 1 . 2005 recs variable response code labels . variable response code label file number* cnfrmhuq .

335

Balanced pressure techniques applied to geothermal drilling  

DOE Green Energy (OSTI)

The objective of the study is to evaluate balanced pressure drilling techniques for use in combating lost circulation in geothermal drilling. Drilling techniques evaluated are: aerated drilling mud, parasite tubing, concentric drill pipe, jet sub, and low density fluids. Based on the present state of the art of balanced pressure drilling techniques, drilling with aerated water has the best overall balance of performance, risk, availability, and cost. Aerated water with a 19:1 free air/water ratio reduce maximum pressure unbalance between wellbore and formation pressures from 1000 psi to 50 psi. This pressure unbalance is within acceptable operating limits; however, air pockets could form and cause pressure surges in the mud system due to high percent of air. Low density fluids used with parasite tubing has the greatest potential for combating lost circulation in geothermal drilling, when performance only is considered. The top portion of the hole would be aerated through the parasite tube at a 10:1 free air/mud ratio and the low density mud could be designed so that its pressure gradient exactly matches the formation pore pressure gradient. The main problem with this system at present is the high cost of ceramic beads needed to produce low density muds.

Dareing, D.W.

1981-08-01T23:59:59.000Z

336

Convolution analysis of surge pressure data  

Science Conference Proceedings (OSTI)

Pressure data from underbalanced perforating or back-surge perforation washing are analyzed by convolution analysis. The method presented allows closed-chamber test evaluation of reservoir transmissivity and wellbore skin by a straight-line graph analogous to a Horner plot. As a well-test analysis method, the closed-chamber test avoids surface pressure buildup, which often prohibits conventional drillstem testing.

Simmons, J.F. (Shell Development Co., Houston, TX (US))

1990-01-01T23:59:59.000Z

337

A practical pressure sensitive computer keyboard  

Science Conference Proceedings (OSTI)

A pressure sensitive computer keyboard is presented that independently senses the force level on every depressed key. The design leverages existing membrane technologies and is suitable for low-cost, high-volume manufacturing. A number of representative ... Keywords: force pressure sensitive keyboard

Paul H. Dietz; Benjamin Eidelson; Jonathan Westhues; Steven Bathiche

2009-10-01T23:59:59.000Z

338

Pressure sensor for high-temperature liquids  

DOE Patents (OSTI)

A pressure sensor for use in measuring pressures in liquid at high temperatures, especially such as liquid sodium or liquid potassium, comprises a soft diaphragm in contact with the liquid. The soft diaphragm is coupled mechanically to a stiff diaphragm. Pressure is measured by measuring the displacment of both diaphragms, typically by measuring the capacitance between the stiff diaphragm and a fixed plate when the stiff diaphragm is deflected in response to the measured pressure through mechanical coupling from the soft diaphragm. Absolute calibration is achieved by admitting gas under pressure to the region between diaphragms and to the region between the stiff diaphragm and the fixed plate, breaking the coupling between the soft and stiff diaphragms. The apparatus can be calibrated rapidly and absolutely.

Forster, George A. (Westmont, IL)

1978-01-01T23:59:59.000Z

339

Pressure Temperature Log | Open Energy Information  

Open Energy Info (EERE)

Page Page Edit with form History Facebook icon Twitter icon » Pressure Temperature Log Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Pressure Temperature Log Details Activities (13) Areas (13) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Downhole Techniques Exploration Sub Group: Well Log Techniques Parent Exploration Technique: Well Log Techniques Information Provided by Technique Lithology: Stratigraphic/Structural: Perturbations in temperature or pressure can be indicative of faults or other structural features Hydrological: fluid cirulation, over-pressured zones, and under-pressured zones. Thermal: Temperature profile with depth Cost Information Low-End Estimate (USD): 0.6060 centUSD 6.0e-4 kUSD

340

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

SciTech Connect

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.

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

1981-10-01T23:59:59.000Z

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


341

Application of pressure and pressure integral functions for the analysis of well test data  

E-Print Network (OSTI)

The analysis of well test data by methods which only use the pressure change can be ambiguous, and analysis using the derivative of the pressure change is often distorted by random error in the data or data noise. Although various "smoothing" techniques have been used to reduce data noise, some concern exists that smoothing procedures may alter the basic character of the data. In this work, we use pressure integral and pressure integral derivative functions to reduce the data noise. First, we perform the conventional semilog analysis on the well test data using the pressure integral functions. Then, we demonstrate the applicability of the pressure change integral and derivative of pressure change integral functions. In this manner we couple the integral functions with the pressure change and pressure change derivative functions to derive useful qualitative and quantitative information from these test data. We also analyze well test data with these methods without the use of superposition time functions such as, Horner time and Agarwal "effective time" functions. In addition, we introduce a numerical technique to generate the pressure integral functions. Thus, we integrate the pressure analysis approach with the pressure integral analysis approach and develop a consistent and applicable method for the analysis of well test data.

Samad, Zahid

1994-01-01T23:59:59.000Z

342

Interannual Variability of Indian Ocean Heat Transport  

Science Conference Proceedings (OSTI)

The work in this paper builds upon the relatively well-studied seasonal cycle of the Indian Ocean heat transport by investigating its interannual variability over a 41-yr period (1958–98). An intermediate, two-and-a-half-layer thermodynamically ...

Galina Chirokova; Peter J. Webster

2006-03-01T23:59:59.000Z

343

Variables optimization of building air conditioning system  

Science Conference Proceedings (OSTI)

A heating and climatizer system based on selective absorption of solar energy by a selective collector. The experimental study shows that the performance of this system depends on several variables: the nature of the colporteur fluid, the flow of the ... Keywords: heating and climatisation, modelation and optimization, solar energy

Marius-Constantin Popescu; Cornelia Aida Bulucea; Gheorghe Manolea; Cristian Vladu

2009-10-01T23:59:59.000Z

344

The Interannual Variability of Tropical Cyclones  

Science Conference Proceedings (OSTI)

This paper examines the interannual variability of tropical cyclones in each of the earth’s cyclone basins using data from 1985 to 2003. The data are first analyzed using a Monte Carlo technique to investigate the long-standing myth that the ...

William M. Frank; George S. Young

2007-10-01T23:59:59.000Z

345

Reuse and variability in large software applications  

Science Conference Proceedings (OSTI)

Reuse has always been a major goal in software engineering, since it promises large gains in productivity, quality and time to market reduction. Practical experience has shown that substantial reuse has only successfully happened in two cases: libraries, ... Keywords: AOP, COTS, EAI, MDA, interoperability, model driven software engineering, process driven application, product families, product line, reuse, variability, workflow

Jacky Estublier; German Vega

2005-09-01T23:59:59.000Z

346

Cloud service selection based on variability modeling  

Science Conference Proceedings (OSTI)

The selection among Cloud services is a recent problem in research and practice. The diversity of decision-relevant criteria, configurability of Cloud services and the need to involve human decision-makers require holistic support through models, methodologies ... Keywords: cloud service selection, decision-making, feature modeling, variability modeling

Erik Wittern; Jörn Kuhlenkamp; Michael Menzel

2012-11-01T23:59:59.000Z

347

Mesoscale Time and Space Wind Variability  

Science Conference Proceedings (OSTI)

The results of a program to study the time and space variability of the wind field below 5 km are presented. Wind data were collected using pilot balloons tracked with the METRAC positioning system. Balloons were launched at 10-30 min intervals ...

W. H. Jasperson

1982-06-01T23:59:59.000Z

348

Anatomy of North Pacific Decadal Variability  

Science Conference Proceedings (OSTI)

A systematic analysis of North Pacific decadal variability in a full-physics coupled ocean–atmosphere model is executed. The model is an updated and improved version of the coupled model studied by Latif and Barnett. Evidence is sought for ...

Niklas Schneider; Arthur J. Miller; David W. Pierce

2002-03-01T23:59:59.000Z

349

Galactic Variable Sky with EGRET and GLAST  

Science Conference Proceedings (OSTI)

The characteristics of the largely-unidentified Galactic sources of gamma rays that were detected by EGRET are reviewed. Proposed source populations that may have the correct spatial, spectral, luminosity, and variability properties to be the origins of the EGRET sources are also presented. Finally, the prospects for studying Galactic gamma-ray sources with the GLAST LAT are reviewed.

Digel, S.W.; /SLAC

2006-11-28T23:59:59.000Z

350

Variation of Area Variables in Regge Calculus  

E-Print Network (OSTI)

We consider the possibility to use the areas of two-simplexes, instead of lengths of edges, as the dynamical variables of Regge calculus. We show that if the action of Regge calculus is varied with respect to the areas of two-simplexes, and appropriate constraints are imposed between the variations, the Einstein-Regge equations are recovered.

Jarmo Makela

1998-01-09T23:59:59.000Z

351

10 X-rays from Cataclysmic Variables  

E-Print Network (OSTI)

Cataclysmic Variables ? (CVs) are a distinct class of interacting binaries, transferring mass from a donor star to a degenerate accretor, a white dwarf (WD). In all observational determinations, and as is required by theory for stable mass transfer, the donor star is of lower mass than the accretor.

Erik Kuulkers; Andrew Norton; Axel Schwope; Brian Warner

2003-01-01T23:59:59.000Z

352

Investigation of determinism in heart rate variability  

Science Conference Proceedings (OSTI)

The article searches for the possible presence of determinism in heart rate variability (HRV) signals by using a new approach based on NARMA (nonlinear autoregressive moving average) modeling and free-run prediction. Thirty-three 256-point HRV time series obtained from Wistar rats submitted to different autonomic blockade protocols are considered

M. E. D. Gomes; A. V. P. Souza; H. N. Guimarães; L. A. Aguirre

2000-01-01T23:59:59.000Z

353

COMPARISON OF VENTED AND ABSOLUTE PRESSURE TRANSDUCERS FOR WATER-LEVEL MONITORING IN HANFORD SITE CENTRAL PLATEAU WELLS  

Science Conference Proceedings (OSTI)

Automated water-level data collected using vented pressure transducers deployed in Hanford Site Central Plateau wells commonly display more variability than manual tape measurements in response to barometric pressure fluctuations. To explain this difference, it was hypothesized that vented pressure transducers installed in some wells are subject to barometric pressure effects that reduce water-level measurement accuracy. Vented pressure transducers use a vent tube, which is open to the atmosphere at land surface, to supply air pressure to the transducer housing for barometric compensation so the transducer measurements will represent only the water pressure. When using vented transducers, the assumption is made that the air pressure between land surface and the well bore is in equilibrium. By comparison, absolute pressure transducers directly measure the air pressure within the wellbore. Barometric compensation is achieved by subtracting the well bore air pressure measurement from the total pressure measured by a second transducer submerged in the water. Thus, no assumption of air pressure equilibrium is needed. In this study, water-level measurements were collected from the same Central Plateau wells using both vented and absolute pressure transducers to evaluate the different methods of barometric compensation. Manual tape measurements were also collected to evaluate the transducers. Measurements collected during this study demonstrated that the vented pressure transducers over-responded to barometric pressure fluctuations due to a pressure disequilibrium between the air within the wellbores and the atmosphere at land surface. The disequilibrium is thought to be caused by the relatively long time required for barometric pressure changes to equilibrate between land surface and the deep vadose zone and may be exacerbated by the restriction of air flow between the well bore and the atmosphere due to the presence of sample pump landing plates and well caps. The disequilibrium is likely limited to wells screened across the water table (i.e., open to the deep vadose zone) where the depth to water is large or a low-permeability layer occurs in the vadose zone. Such wells are a pathway for air movement between the deep vadose zone and land surface and this sustains the pressure disequilibrium between the well bore and the atmosphere for longer time periods. Barometric over-response was not observed with the absolute pressure transducers because barometric compensation was achieved by directly measuring the air pressure within the well. Users of vented pressure transducers should be aware of the over-response issue in certain Hanford Site wells and ascertain if it will affect the use of the data. Pressure disequilibrium between the well and the atmosphere can be identified by substantial air movement through the wellbore. In wells exhibiting pressure disequilibrium, it is recommended that absolute pressure transducers be used rather than vented transducers for applications that require precise automated determinations of well water-level changes in response to barometric pressure fluctuations.

MCDONALD JP

2011-09-08T23:59:59.000Z

354

CHARACTERIZING THE OPTICAL VARIABILITY OF BRIGHT BLAZARS: VARIABILITY-BASED SELECTION OF FERMI ACTIVE GALACTIC NUCLEI  

SciTech Connect

We investigate the use of optical photometric variability to select and identify blazars in large-scale time-domain surveys, in part to aid in the identification of blazar counterparts to the {approx}30% of {gamma}-ray sources in the Fermi 2FGL catalog still lacking reliable associations. Using data from the optical LINEAR asteroid survey, we characterize the optical variability of blazars by fitting a damped random walk model to individual light curves with two main model parameters, the characteristic timescales of variability {tau}, and driving amplitudes on short timescales {sigma}-circumflex. Imposing cuts on minimum {tau} and {sigma}-circumflex allows for blazar selection with high efficiency E and completeness C. To test the efficacy of this approach, we apply this method to optically variable LINEAR objects that fall within the several-arcminute error ellipses of {gamma}-ray sources in the Fermi 2FGL catalog. Despite the extreme stellar contamination at the shallow depth of the LINEAR survey, we are able to recover previously associated optical counterparts to Fermi active galactic nuclei with E {>=} 88% and C = 88% in Fermi 95% confidence error ellipses having semimajor axis r < 8'. We find that the suggested radio counterpart to Fermi source 2FGL J1649.6+5238 has optical variability consistent with other {gamma}-ray blazars and is likely to be the {gamma}-ray source. Our results suggest that the variability of the non-thermal jet emission in blazars is stochastic in nature, with unique variability properties due to the effects of relativistic beaming. After correcting for beaming, we estimate that the characteristic timescale of blazar variability is {approx}3 years in the rest frame of the jet, in contrast with the {approx}320 day disk flux timescale observed in quasars. The variability-based selection method presented will be useful for blazar identification in time-domain optical surveys and is also a probe of jet physics.

Ruan, John J.; Anderson, Scott F.; MacLeod, Chelsea L.; Becker, Andrew C.; Davenport, James R. A.; Ivezic, Zeljko [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Burnett, T. H. [Department of Physics, University of Washington, Seattle, WA 98195-1560 (United States); Kochanek, Christopher S. [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Plotkin, Richard M. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States); Sesar, Branimir [Division of Physics, Mathematics and Astronomy, Caltech, Pasadena, CA 91125 (United States); Stuart, J. Scott, E-mail: jruan@astro.washington.edu [Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, MA 02420-9108 (United States)

2012-11-20T23:59:59.000Z

355

Electrochemical cell having improved pressure vent  

DOE Patents (OSTI)

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.

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

1993-01-01T23:59:59.000Z

356

Particle pressures in fluidized beds. Final report  

SciTech Connect

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.

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

1996-09-01T23:59:59.000Z

357

Particle Pressures in Fluidized Beds. Final report  

SciTech Connect

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.

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

1996-09-01T23:59:59.000Z

358

Assessment of fiber optic pressure sensors  

SciTech Connect

This report presents the results of a six-month Phase 1 study to establish the state-of-the-art in fiber optic pressure sensing and describes the design and principle of operation of various fiber optic pressure sensors. This study involved a literature review, contact with experts in the field, an industrial survey, a site visit to a fiber optic sensor manufacturer, and laboratory testing of a fiber optic pressure sensor. The laboratory work involved both static and dynamic performance tests. In addition, current requirements for environmental and seismic qualification of sensors for nuclear power plants were reviewed to determine the extent of the qualification tests that fiber optic pressure sensors may have to meet before they can be used in nuclear power plants. This project has concluded that fiber optic pressure sensors are still in the research and development stage and only a few manufacturers exist in the US and abroad which supply suitable fiber optic pressure sensors for industrial applications. Presently, fiber optic pressure sensors are mostly used in special applications for which conventional sensors are not able to meet the requirements.

Hashemian, H.M.; Black, C.L.; Farmer, J.P. [Analysis and Measurement Services Corp., Knoxville, TN (United States)

1995-04-01T23:59:59.000Z

359

A Bayesian decision theory approach to variable selection for discrimination  

Science Conference Proceedings (OSTI)

Motivated by examples in spectroscopy, we study variable selection for discrimination in problems with very many predictor variables. Assuming multivariate normal distributions with common variance for the predictor variables within groups, we develop ... Keywords: Bayes, decision theory, discriminant analysis, near infrared spectroscopy, simulated annealing, variable selection

T. Fearn; P. J. Brown; P. Besbeas

2002-07-01T23:59:59.000Z

360

Variable selection and ranking for analyzing automobile traffic accident data  

Science Conference Proceedings (OSTI)

Variable ranking and feature selection are important concepts in data mining and machine learning. This paper introduces a new variable ranking technique named Sum Max Gain Ratio (SMGR). The new technique is evaluated within the domain of traffic accident ... Keywords: decision tree, traffic accident data, variable and feature selection, variable ranking

Huanjing Wang; Allen Parrish; Randy K. Smith; Susan Vrbsky

2005-03-01T23:59:59.000Z

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


361

Eddy current technique for predicting burst pressure  

DOE Patents (OSTI)

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.

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

362

Pressurized security barrier and alarm system  

DOE Patents (OSTI)

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.

Carver, D.W.

1994-12-31T23:59:59.000Z

363

RHIC PRESSURE RISE AND ELECTRON CLOUD.  

SciTech Connect

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.

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

364

Pressurized security barrier and alarm system  

DOE Patents (OSTI)

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.

Carver, D.W.

1995-04-11T23:59:59.000Z

365

Pressurized security barrier and alarm system  

DOE Patents (OSTI)

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.

Carver, Don W. (Knoxville, TN)

1995-01-01T23:59:59.000Z

366

Effect of process variables on the quality attributes of briquettes from wheat, oat, canola and barley  

DOE Green Energy (OSTI)

Effect of process variables on the quality attributes of briquettes from wheat, oat, canola and barley straw Jaya Shankar Tumuluru*, L. G. Tabil, Y. Song, K. L. Iroba and V. Meda Biomass is a renewable energy source and environmentally friendly substitute for fossil fuels such as coal and petroleum products. Major limitation of biomass for successful energy application is its low bulk density, which makes it very difficult and costly to transport and handle. To overcome this limitation, biomass has to be densified. The commonly used technologies for densification of biomass are pelletization and briquetting. Briquetting offers many advantages at it can densify larger particles sizes of biomass at higher moisture contents. Briquetting is influenced by a number of feedstock and process variables such as moisture content, particle size distribution, and some operating variables such as temperature and densification pressure. In the present study, experiments were designed and conducted based on Box-Behnken design to produce briquettes using barley, wheat, canola and barley straws. A laboratory scale hydraulic briquette press was used for the present study. The experimental process variables and their levels used in the present study were pressure levels (7.5, 10, 12.5 MPa), three levels of temperature (90, 110, 130 C), at three moisture content levels (9, 12, 15% w.b.), and three levels of particle size (19.1, 25.04, 31.75 mm). The quality variables studied includes moisture content, initial density and final briquette density after two weeks of storage, size distribution index and durability. The raw biomass was initially chopped and size reduced using a hammer mill. The ground biomass was conditioned at different moisture contents and was further densified using laboratory hydraulic press. For each treatment combination, ten briquettes were manufactured at a residence time of about 30 s after compression pressure setpoint was achieved. After compression, the initial dimensions and the final dimensions after 2 weeks of storage in controlled environment of all the samples were measured. Durability, dimensional stability, and moisture content tests were conducted after two weeks of storage of the briquettes produced. Initial results indicated that moisture content played a significant role on briquettes durability, stability, and density. Low moisture content of the straws (7-12%) gave more durable briquettes. Briquette density increased with increasing pressure depending on the moisture content value. The axial expansion was more significant than the lateral expansion, which in some cases tended to be nil depending on the material and operating variables. Further data analysis is in progress in order to understand the significance of the process variables based on ANOVA. Regression models were developed to predict the changes in quality of briquettes with respect of the process variables under study. Keywords: Herbaceous biomass, densification, briquettes, density, durability, dimensional stability, ANOVA and regression equations

Jaya Shankar Tumuluru

2011-08-01T23:59:59.000Z

367

Variables Affecting Economic Development of Wind Energy  

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

Variables Affecting Economic Variables Affecting Economic Development of Wind Energy E. Lantz and S. Tegen National Renewable Energy Laboratory Presented at WINDPOWER 2008 Houston, Texas June 1-4, 2008 Conference Paper NREL/CP-500-43506 July 2008 NREL is operated by Midwest Research Institute ● Battelle Contract No. DE-AC36-99-GO10337 NOTICE The submitted manuscript has been offered by an employee of the Midwest Research Institute (MRI), a contractor of the US Government under Contract No. DE-AC36-99GO10337. Accordingly, the US Government and MRI retain a nonexclusive royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes. This report was prepared as an account of work sponsored by an agency of the United States government.

368

Thermodynamics in variable speed of light theories  

SciTech Connect

The perfect fluid in the context of a covariant variable speed of light theory proposed by J. Magueijo is studied. On the one hand the modified first law of thermodynamics together with a recipe to obtain equations of state are obtained. On the other hand the Newtonian limit is performed to obtain the nonrelativistic hydrostatic equilibrium equation for the theory. The results obtained are used to determine the time variation of the radius of Mercury induced by the variability of the speed of light (c), and the scalar contribution to the luminosity of white dwarfs. Using a bound for the change of that radius and combining it with an upper limit for the variation of the fine structure constant, a bound on the time variation of c is set. An independent bound is obtained from luminosity estimates for Stein 2015B.

Racker, Juan [CONICET, Centro Atomico Bariloche, Avenida Bustillo 9500 (8400), San Carlos De Bariloche (Argentina); Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900), La Plata (Argentina); Sisterna, Pablo [Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3350 (7600), Mar del Plata (Argentina); Vucetich, Hector [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900), La Plata (Argentina)

2009-10-15T23:59:59.000Z

369

Discrete variable theory of triatomic photodissociation  

SciTech Connect

The coupled equations describing the photodissociation process are expressed in the discrete variable representation (DVR) in which the coupled equations are labeled by quadrature points rather than by internal basis functions. A large reduction in the dimensionality of the coupled equations can be realized since the spatially localized bound state nuclear wave function vanishes at most of the quadrature points, making only certain orientations of the fragments important in the region of strong interaction (small separation). The discrete variable theory of photodissociation is applied to the model dissociation of bent HCN in which the CN fragment is treated as a rigid rotor. The truncated DVR rotational distributions are compared with the exact close coupled rotational distributions, and excellent agreement with greatly reduced dimensionality of the equations is found.

Heather, R.W.; Light, J.C.

1983-07-01T23:59:59.000Z

370

Solar energy: some variables influencing increased utilization  

SciTech Connect

The mid 1970s energy crisis encouraged the growth of alternative fuels. Through the late 1970s and 1980s, solar energy was the primary alternative fuel. Federal and state programs encouraged the growth of residential solar installations through the use of tax credits. This dissertation used data from the eleven western states to assess tax credits' influence on residential solar installations. A Spearman's r was used to evaluate the role of tax credits on the percent increase in solar systems from 1980 to 1984. The r/sub s/ was .93. The second portion of the analysis used contingency tables to see if variables other than tax credits influence solar installations; the results showed tax credits + solar radiation and fuel mix are the significant variables. The final chapter looks at municipal solar utilities, tax on excessive energy use, a public/private solar research lab, and building rating system as means to supplement solar energy tax credits.

Born, B.E.

1986-01-01T23:59:59.000Z

371

Thermodynamics in variable speed of light theories  

E-Print Network (OSTI)

The perfect fluid in the context of a covariant variable speed of light theory proposed by J. Magueijo is studied. On the one hand the modified first law of thermodynamics together with a recipe to obtain equations of state are obtained. On the other hand the Newtonian limit is performed to obtain the nonrelativistic hydrostatic equilibrium equation for the theory. The results obtained are used to determine the time variation of the radius of Mercury induced by the variability of the speed of light ($c$), and the scalar contribution to the luminosity of white dwarfs. Using a bound for the change of that radius and combining it with an upper limit for the variation of the fine structure constant, a bound on the time variation of $c$ is set. An independent bound is obtained from luminosity estimates for Stein 2015B.

Juan Racker; Pablo Sisterna; Hector Vucetich

2007-11-06T23:59:59.000Z

372

Review of Variable Generation Integration Charges  

DOE Green Energy (OSTI)

The growth of wind and solar generation in the United States, and the expectation of continued growth of these technologies, dictates that the future power system will be operated in a somewhat different manner because of increased variability and uncertainty. A small number of balancing authorities have attempted to determine an 'integration cost' to account for these changes to their current operating practices. Some balancing authorities directly charge wind and solar generators for integration charges, whereas others add integration charges to projected costs of wind and solar in integrated resource plans or in competitive solicitations for generation. This report reviews the balancing authorities that have calculated variable generation integration charges and broadly compares and contrasts the methodologies they used to determine their specific integration charges. The report also profiles each balancing authority and how they derived wind and solar integration charges.

Porter, K.; Fink, S.; Buckley, M.; Rogers, J.; Hodge, B. M.

2013-03-01T23:59:59.000Z

373

CVcat: an interactive database on cataclysmic variables  

E-Print Network (OSTI)

CVcat is a database that contains published data on cataclysmic variables and related objects. Unlike in the existing online sources, the users are allowed to add data to the catalogue. The concept of an ``open catalogue'' approach is reviewed together with the experience from one year of public usage of CVcat. New concepts to be included in the upcoming AstroCat framework and the next CVcat implementation are presented. CVcat can be found at http://www.cvcat.org.

J. Kube; B. T. Gaensicke; F. Euchner; B. Hoffmann

2003-04-29T23:59:59.000Z

374

Bessel-Zernike Discrete Variable Representation Basis  

SciTech Connect

The connection between the Bessel discrete variable basis expansion and a specific form of an orthogonal set of Jacobi polynomials is demonstrated. These so-called Zernike polynomials provide alternative series expansions of suitable functions over the unit interval. Expressing a Bessel function in a Zernike expansion provides a straightforward method of generating series identities. Furthermore, the Zernike polynomials may also be used to efficiently evaluate the Hankel transform for rapidly decaying functions or functions with finite support.

Cerjan, C J

2005-10-24T23:59:59.000Z

375

Mobile Variable Depth Sampling System Design Study  

Science Conference Proceedings (OSTI)

A design study is presented for a mobile, variable depth sampling system (MVDSS) that will support the treatment and immobilization of Hanford LAW and HLW. The sampler can be deployed in a 4-inch tank riser and has a design that is based on requirements identified in the Level 2 Specification (latest revision). The waste feed sequence for the MVDSS is based on Phase 1, Case 3S6 waste feed sequence. Technical information is also presented that supports the design study.

BOGER, R.M.

2000-08-25T23:59:59.000Z

376

Variability of PV on Distribution Systems  

Science Conference Proceedings (OSTI)

In 2010, the Electric Power Research Institute (EPRI) along with several utilities began collecting high-resolution monitoring data on distributed solar photovoltaic (PV) systems throughout the United States. Included in these monitoring data are single-module PV systems distributed along selected feeders as well as several larger PV systems (up to 1.4 MW). Utilizing data from these sites, this report focuses specifically on examining the measured variability of solar PV distributed throughout a ...

2012-12-13T23:59:59.000Z

377

Changes in heart rate variability during fainting  

Science Conference Proceedings (OSTI)

Studies of heart rate variability in people who faint may yield insights into normal physiologic mechanisms which probably are dynamic. These insights might be gained because fainting appears to be due to a breakdown of these mechanisms. Tilt table testing reliably induces fainting in patients with a history of fainting and can be used to study these mechanisms. During tilt tests ending in fainting heart rate changes markedly

Robert Sheldon; Kenneth Riff

1991-01-01T23:59:59.000Z

378

Documentation Requirements for Pressurized Experiment Equipment  

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

Documentation Requirements for Pressurized Experiment Apparatus 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, whether it is to be used on a beamline during a measurement or in a laboratory to prepare the sample prior to the experiment, the hazards associated with the equipment must be reviewed. To review the equipment and make any recommendations, a certain level of documentation must be provided by the experimenter. The length and depth of the documentation should be commensurate with the complexity of the system. 1. Description of apparatus a. Description of the assembly and operation of the system. b. State the maximum working pressure, working fluid (liquid or gas) used to

379

Pressurization of whole element canister during staging  

DOE Green Energy (OSTI)

An analytical model was developed to estimate the buildup of gas pressure for a single outer element in a hot cell test container for a post cold vacuum drying staging/storage test. This model considers various sources of gas generation and gas consumption as a function of time. In a canister containing spent nuclear fuel, hydrogen is generated from the reactions of uranium with free water or hydrated water, hydride decomposition, and radiolysis. The canister pressurization model predicts a stable pressure and a peak temperature during staging, with an assumption that a fuel element contains 40 gm of corrosion products and a decay heat of 2.07 or 1.06 Watts. Calculations were also performed on constant temperature tests for fuel elements containing varied amounts of sludge tested at 150, 125, 105, and 85 C. The pressurization model will be used to evaluate test results obtained from post-drying testing on whole fuel elements.

Huang, F.F.

1998-01-27T23:59:59.000Z

380

Practical Conversion of Pressure to Depth  

Science Conference Proceedings (OSTI)

A conversion formula between pressure and depth is obtained employing the recently adopted equation of state for seawater (Millero et al., 1980). Assuming the ocean of uniform salinity 35 NSU and temperature 0°C the following equation is proposed,...

Peter M. Saunders

1981-04-01T23:59:59.000Z

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


381

A Revised Hurricane Pressure–Wind Model  

Science Conference Proceedings (OSTI)

A new technique for relating central pressure and maximum winds in tropical cyclones is presented, together with a method of objectively determining a derivative of the Holland b parameter, bs, which relates directly to surface winds and varies ...

Greg Holland

2008-09-01T23:59:59.000Z

382

Radiative Measurements of Pressure Modulator Operation  

Science Conference Proceedings (OSTI)

The pressure modulator is extensively used in atmospheric measurements but is not well characterized in terms of its spectroscopic operation. A series of measurements on a carbon monoxide radiometer is described and comparisons are made with ...

J. R. Drummond; A. Ashton

1990-02-01T23:59:59.000Z

383

Stationary High-Pressure Hydrogen Storage  

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

Stationary High-Pressure Hydrogen Storage Zhili Feng Oak Ridge National Laboratory 2 Managed by UT-Battelle for the U.S. Department of Energy Technology Gap Analysis for Bulk...

384

Basic Meteorological Observations for Schools: Atmospheric Pressure  

Science Conference Proceedings (OSTI)

This article addresses measurement of atmospheric surface pressure using economical instruments. It is intended to provide members of the Society with a ready reference to respond to inquiries from earth and physical science teachers at the ...

John T. Snow; Michelle E. Akridge; Shawn B. Harley

1992-06-01T23:59:59.000Z

385

Vapor Pressure Measurement of Supercooled Water  

Science Conference Proceedings (OSTI)

A new dewpoint hygrometer was developed for subfreezing temperature application. Vapor pressure of supercooled water was determined by measuring temperatures at the dew-forming surface and the vapor source ice under the flux density balance, and ...

N. Fukuta; C. M. Gramada

2003-08-01T23:59:59.000Z

386

Mars Atmosphere Pressure Periodicities from Viking Observations  

Science Conference Proceedings (OSTI)

The first martian year of pressure data taken by the Viking landers on Mars is subjected to power spectrum analysis. The analysis suggests that strong periodicities are present in the martian atmosphere, especially at the high-latitude (48°N) ...

R. D. Sharman; J. A. Ryan

1980-09-01T23:59:59.000Z

387

Statistics of the Global Tropopause Pressure  

Science Conference Proceedings (OSTI)

Statistics of the global tropopause pressure are evaluated for the period between 1979 and 1993. The analysis is based on gridded data as provided by the ECMWF reanalysis project. The thermal and dynamical definitions of the tropopause are ...

Klaus P. Hoinka

1998-12-01T23:59:59.000Z

388

Decommissioning: Reactor Pressure Vessel Internals Segmentation  

Science Conference Proceedings (OSTI)

Decommissioning a nuclear plant covers a wide variety of challenging projects. One of the most challenging areas is the removal and disposal of the reactor pressure vessel (RPV) and the RPV internals. This report describes commercial reactor pressure vessel segmentation projects that have been completed and discusses several projects that are still in the planning stages. The report also covers lessons learned from each project.

2001-10-11T23:59:59.000Z

389

Pressure limits of an axisymmetric torus  

SciTech Connect

In order to clarify the pressure limit of a toroidal plasma equilibrium in a three-dimensional geometry, an azimuthally symmetric toroidal plasma was considered. In a tokamak-like plasma, the net toroidal current is necessary for a finite ..beta.. plasma equilibrium. If external conductors are used to provide the rotational transform, iota, the plasma pressure is limited to ..beta.. = (iota/2..pi..)/sup 2//2A, where A is the aspect ratio.

Yoshikawa, S.

1986-03-01T23:59:59.000Z

390

Pressure responsive perforating and testing system  

Science Conference Proceedings (OSTI)

In accordance with an illustrative embodiment of the present invention, a well perforating and testing system includes packer and test valve means for respectively isolating a well bore interval and controlling flow of well fluids therefrom, a perforating gun connected below the packer means, and firing means responsive to a greater pressure in the well annulus above the packer means than in said isolated interval for actuating the perforating gun so theat the casing can be perforated at underbalanced pressure conditions.

Upchurch, J. M.

1985-04-09T23:59:59.000Z

391

Steam Pressure Reduction, Opportunities, and Issues  

Science Conference Proceedings (OSTI)

Steam pressure reduction has the potential to reduce fuel consumption for a minimum capital investment. When the pressure at the boiler is reduced, fuel and steam are saved as a result of changes in the high-pressure side of the steam system from the boiler through the condensate return system. In the boiler plant, losses from combustion, boiler blowdown, radiation, and steam venting from condensate receivers would be reduced by reducing steam pressure. Similarly, in the steam distribution system, losses from radiation, flash steam vented from condensate receivers, and component and steam trap leakage would also be reduced. There are potential problems associated with steam pressure reduction, however. These may include increased boiler carryover, boiler water circulation problems in watertube boilers, increased steam velocity in piping, loss of power in steam turbines, and issues with pressure reducing valves. This paper is based a Steam Technical Brief sponsored by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy and Enbridge Gas Distribution, Inc. (5). An example illustrates the use of DOE BestPractices Steam System Assessment Tool to model changes in steam, fuel, electricity generation, and makeup water and to estimate resulting economic benefits.

Berry, Jan [ORNL; Griffin, Mr. Bob [Enbridge Gas Distribution, Inc.; Wright, Anthony L [ORNL

2006-01-01T23:59:59.000Z

392

Dynamic surge/swab pressure predictions  

SciTech Connect

It is generally accepted that the pulling and running of pipe causes pressure surges. The prediction of pressure surges is of economic importance in wells where the pressure must be examined within narrow limits to prevent lost circulation and formation-fluid influx. For these wells, the drilling engineer needs the best possible method of calculating surge pressures to drill wells with a minimum of trouble. This paper presents a dynamic surge/swab model that extends existing technology with the following features: (1) pipe and annulus pressures are coupled through the pipe elasticity; (2) longitudinal pipe elasticity and fluid viscous forces determine pipe displacement; (3) fluid properties vary as a function of temperature and pressure; and (4) formation elasticity; pipe elasticity, and cement elasticity are all used to determine the composite elastic response of the wellbore. Comparisons between the model and field data demonstrate good agreement. Data matches have been made for both water- and oil-based muds in both shallow and deep wells. Furthermore, the model matches data that had not been previously matched by other models.

Mitchell, R.F. (Enertech Engineering and Research (US))

1988-09-01T23:59:59.000Z

393

Fluctuating pressure correlations in wall turbulence  

E-Print Network (OSTI)

The purpose of the present paper is to study the influence of wall-echo on pressure fluctuations $p'$, and on statistical correlations containing $p'$, {\\em viz} redistribution $\\phi_{ij}$ and pressure diffusion $d_{ij}^{(p)}$. We extend the usual analysis of turbulent correlations containing pressure fluctuations in wall-bounded \\tsc{dns} computations [Kim J.: {\\em J. Fluid Mech.} {\\bf 205} (1989) 421--451], separating $p'$ not only into rapid $p_{(\\mathrm{r})}'$ and slow $p_{(\\mathrm{s})}'$ parts [Chou P.Y.: {\\em Quart. Appl. Math.} {\\bf 3} (1945) 38--54], but further into volume (weakly inhomogeneous; $p'_{(\\mathrm{r};\\mathfrak{V})}$ and $p'_{(\\mathrm{s};\\mathfrak{V})}$) and surface (strongly inhomogeneous wall-echo; $p'_{(\\mathrm{r};w)}$ and $p'_{(\\mathrm{s};w)}$) terms. An algorithm, based on a Green's function approach, is developed to compute the above splittings for various correlations containing pressure fluctuations (redistribution, pressure diffusion, velocity/pressure-gradient), in fully develope...

Gerolymos, G A; Senechal, D; Vallet, I

2013-01-01T23:59:59.000Z

394

NETL: Gasification Systems - Development of High-Pressure Dry...  

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

Feed Systems Development of High-Pressure Dry Feed Pump for Gasification Systems Project Number: DE-FC26-04NT42237 High-Pressure Solids Pump High-Pressure Solids Pump Pratt &...

395

NETL: Gasification Systems - Development of High-Pressure Dry...  

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

High-Pressure Dry Feed Pump for Gasification Systems Project No.: DE-FC26-04NT42237 High-Pressure Solids Pump High-Pressure Solids Pump Pratt & Whitney Rocketdyne (PWR) is...

396

An Inexpensive Method for Measurements of Static Pressure Fluctuations  

Science Conference Proceedings (OSTI)

An application of a commercially available and inexpensive pressure probe and transducer, originally designed for pressure drop measurements in air conditioning conduits, is suggested for accurate and reliable measurements of static pressure ...

Dan Liberzon; Lev Shemer

2010-04-01T23:59:59.000Z

397

Reexamination of Tropical Cyclone Wind–Pressure Relationships  

Science Conference Proceedings (OSTI)

Tropical cyclone wind–pressure relationships are reexamined using 15 yr of minimum sea level pressure estimates, numerical analysis fields, and best-track intensities. Minimum sea level pressure is estimated from aircraft reconnaissance or ...

John A. Knaff; Raymond M. Zehr

2007-02-01T23:59:59.000Z

398

Meso-?-scale Pressure Dips Associated with Typhoons  

Science Conference Proceedings (OSTI)

Using a mesoscale model, the formation process of a pressure dip, which was characterized by a rapid decrease and subsequent increase in surface pressure lasting less than an hour, was investigated. A simulated pressure dip accompanied by Typhoon ...

Hironori Fudeyasu; Satoshi Iizuka; Taiichi Hayashi

2007-04-01T23:59:59.000Z

399

An Investigation of Gas Bubble Generation and Measurement in Water and Mercury.  

E-Print Network (OSTI)

??The pressure increase attributed to the energy deposition in the liquid metal target of the Spallation Neutron Source results in cavitation and pitting erosion of… (more)

Walker, Stuart A

2010-01-01T23:59:59.000Z

400

Empowering Variable Renewables: Options for Flexible Electricity Systems |  

Open Energy Info (EERE)

Empowering Variable Renewables: Options for Flexible Electricity Systems Empowering Variable Renewables: Options for Flexible Electricity Systems Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Empowering Variable Renewables: Options for Flexible Electricity Systems Agency/Company /Organization: International Energy Agency Sector: Energy Focus Area: Renewable Energy Topics: Market analysis, Technology characterizations Resource Type: Publications Website: www.iea.org/g8/2008/Empowering_Variable_Renewables.pdf Empowering Variable Renewables: Options for Flexible Electricity Systems Screenshot References: Empowering Variable Renewables: Options for Flexible Electricity Systems[1] Summary "Increasing the share of renewables in energy portfolios is a key tool in the drive to reduce anthropogenic carbon dioxide emissions, as well as

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


401

Climatic variability within an equilibrium greenhouse simulation  

SciTech Connect

A simulation of the possible consequences of a doubling of the CO{sub 2} content of the atmosphere has been performed with a low resolution global climatic model. The model included the diurnal and seasonal computed sea ice amount and cloud cover, and used implied oceanic heat fluxes to represent transport processes in the oceans. A highly responsive 2-layer soil moisture formulation was also incorporated. Twenty year equilibrated simulations for control (1xCO{sub 2}) and greenhouse (2xCO{sub 2}) conditions were generated. The major emphasis of the analysis presented here is on the intra-annual and interannual variability of the greenhouse run with respect to the control run. This revealed considerable differences from the time-averaged results with occasions of marked positive and negative temperature deviations. Of particular interest were the periods of negative temperature departures compared to the control run which were identified, especially over the Northern Hemisphere continents. Temporal and spatial precipitation and soil moisture anomalies also occurred, some of which were related to the surface temperature changes. Substantial sea surface temperature anomalies were apparent in the greenhouse run, indicating that a source of climatic forcing existed in addition to that due to doubling of the CO{sub 2}. Comparison of the intra-annual and interannual variability of the control run with that of the greenhouse run suggests that, in many situations, it will be difficult to identify a greenhouse signal against the intrinsic natural variability of the climatic system. 35 refs., 20 figs., 1 tab.

Gordon, H.B.; Hunt, B.G. [CSIRO Division of Atmospheric Research, Victoria (Austria)

1994-01-01T23:59:59.000Z

402

Allocating Variability and Reserve Requirements (Presentation)  

SciTech Connect

This presentation describes how you could conceivably allocate variability and reserve requirements, including how to allocate aggregation benefits. Conclusions of this presentation are: (1) Aggregation provides benefits because individual requirements are not 100% correlated; (2) Method needed to allocate reduced requirement among participants; (3) Differences between allocation results are subtle - (a) Not immediately obvious which method is 'better'; (b) Many are numerically 'correct', they sum to the physical requirement; (c) Many are not 'fair', Results depend on sub-aggregation and/or the order individuals are included; and (4) Vector allocation method is simple and fair.

Kirby, B.; King, J.; Milligan, M.

2011-10-01T23:59:59.000Z

403

Long-Term Wind Power Variability  

DOE Green Energy (OSTI)

The National Renewable Energy Laboratory started collecting wind power data from large commercial wind power plants (WPPs) in southwest Minnesota with dedicated dataloggers and communication links in the spring of 2000. Over the years, additional WPPs in other areas were added to and removed from the data collection effort. The longest data stream of actual wind plant output is more than 10 years. The resulting data have been used to analyze wind power fluctuations, frequency distribution of changes, the effects of spatial diversity, and wind power ancillary services. This report uses the multi-year wind power data to examine long-term wind power variability.

Wan, Y. H.

2012-01-01T23:59:59.000Z

404

Allocating Variability and Reserve Requirements (Presentation)  

DOE Green Energy (OSTI)

This presentation describes how you could conceivably allocate variability and reserve requirements, including how to allocate aggregation benefits. Conclusions of this presentation are: (1) Aggregation provides benefits because individual requirements are not 100% correlated; (2) Method needed to allocate reduced requirement among participants; (3) Differences between allocation results are subtle - (a) Not immediately obvious which method is 'better'; (b) Many are numerically 'correct', they sum to the physical requirement; (c) Many are not 'fair', Results depend on sub-aggregation and/or the order individuals are included; and (4) Vector allocation method is simple and fair.

Kirby, B.; King, J.; Milligan, M.

2011-10-01T23:59:59.000Z

405

Constraints on Area Variables in Regge Calculus  

E-Print Network (OSTI)

We describe a general method of obtaining the constraints between area variables in one approach to area Regge calculus, and illustrate it with a simple example. The simplicial complex is the simplest tessellation of the 4-sphere. The number of independent constraints on the variations of the triangle areas is shown to equal the difference between the numbers of triangles and edges, and a general method of choosing independent constraints is described. The constraints chosen by using our method are shown to imply the Regge equations of motion in our example.

Jarmo Makela; Ruth M. Williams

2000-11-02T23:59:59.000Z

406

Constraints on Area Variables in Regge Calculus  

E-Print Network (OSTI)

We describe a general method of obtaining the constraints between area variables in one approach to area Regge calculus, and illustrate it with a simple example. The simplicial complex is the simplest tessellation of the 4-sphere. The number of independent constraints on the variations of the triangle areas is shown to equal the difference between the numbers of triangles and edges, and a general method of choosing independent constraints is described. The constraints chosen by using our method are shown to imply the Regge equations of motion in our example.

Mäkelä, J M; Makela, Jarmo; Williams, Ruth M.

2001-01-01T23:59:59.000Z

407

Measurements of Vapor Pressures and PVT Properties for n ...  

Science Conference Proceedings (OSTI)

Page 1. Measurements of Vapor Pressures and PVT Properties for n-Butane from 280 to 440 K at Pressures to 200 MPa ...

2006-07-20T23:59:59.000Z

408

Roadmap for Nondestructive Evaluation of Reactor Pressure Vessel...  

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

of Reactor Pressure Vessel Research and Development by the Light Water Reactor Sustainability Program Roadmap for Nondestructive Evaluation of Reactor Pressure Vessel Research...

409

Reactor Pressure Vessel Task of Light Water Reactor Sustainability...  

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

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Milestone Report on Materials and Machining of Specimens for the ATR-2 Experiment Reactor Pressure...

410

Studies in Magnetism and Superconductivity under Extreme Pressure.  

E-Print Network (OSTI)

??Abstract Studies of superconductivity, magnetism and structure under pressure have made important contributions to furthering our understanding of the physical properties of materials. High pressure… (more)

Bi, Wenli

2011-01-01T23:59:59.000Z

411

Pressure Temperature Log At Maui Area (DOE GTP) | Open Energy...  

Open Energy Info (EERE)

Pressure Temperature Log At Maui Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Pressure Temperature Log At Maui Area (DOE GTP)...

412

A Gas Pressure Scale Based on Primary Standard Piston ...  

Science Conference Proceedings (OSTI)

A Gas Pressure Scale Based on Primary Standard Piston Gauges. Summary: ... Distortion is a major contributor to uncertainty at higher pressures. ...

2013-06-07T23:59:59.000Z

413

BILIWG Meeting: High Pressure Steam Reforming of Bio-Derived...  

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

at high pressures yields more methane, less hydrogen at thermodynamic equilibrium Coke formation tendency increases with increasing pressures Coking tendency can be...

414

Subsea Mudlift Drilling: evaluation of the pressure differential problem with subsea pump  

E-Print Network (OSTI)

The petroleum industry is trying to develop new and improved technology to safely, successfully and profitably extract hydrocarbons in deep water. One such technology under development is subsea mudlift drilling (SMD), a joint industry project with nine companies participating. In subsea mudlift drilling the mud returns do not go through the drilling riser as in conventional drilling, but instead they go through one or more smaller diameter return lines back to the surface. This is made possible by the use of a set of subsea pumps located on the ocean floor that will take suction from the annulus side of the wellbore. The subsea pump acts as a choke that can be "opened" or "closed" by adjusting the pump rate in order to keep the bottom hole pressure constant. The pump is designed to do this as long as the outlet pressure does not fall more than 500 psi below the inlet pressure. If the outlet pressure falls more than 500 psi below the inlet pressure, the pump will not be able to handle this differential and the fluid will flow through the pump due to a pressure reversal. This would result in a loss of bottom hole pressure. The purpose of this thesis is to investigate this pressure differential problem to determine the operating conditions under which a pressure reversal will occur, and to see for what kick scenarios this becomes a problem. One way to counteract the pressure reversal is to apply backpressure at the surface choke. The effect of applying various levels of backpressure is investigated in this thesis. Possible complications resulting from this remedy, such as increased flow rates of gas from the well during well control operations, are also evaluated. A major conclusion from this study is that the solution of applying backpressure through a surface choke is a valid and functional solution. This thesis also explains the effect of various variables on u-tubing rate and mud level drop in subsea mudlift drilling. The major conclusion here is that the driving forces behind the u-tube are water depth and mud weight.

Johansen, Tarjei

2000-01-01T23:59:59.000Z

415

HIGH PRESSURE COAL COMBUSTON KINETICS PROJECT  

SciTech Connect

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.

Stefano Orsino

2005-03-30T23:59:59.000Z

416

Automatic Misconfiguration Troubleshooting with PeerPressure  

E-Print Network (OSTI)

Technical support contributes 17 % of the total cost of ownership of today’s desktop PCs [25]. An important element of technical support is troubleshooting misconfigured applications. Misconfiguration troubleshooting is particularly challenging, because configuration information is shared and altered by multiple applications. In this paper, we present a novel troubleshooting system: PeerPressure, which uses statistics from a set of sample machines to diagnose the root-cause misconfigurations on a sick machine. This is in contrast with methods that require manual identification on a healthy machine for diagnosing misconfigurations [30]. The elimination of this manual operation makes a significant step towards automated misconfiguration troubleshooting. In PeerPressure, we introduce a ranking metric for misconfiguration candidates. This metric is based on empirical Bayesian estimation. We have prototyped a PeerPressure troubleshooting system and used a database of 87 machine configuration snapshots to evaluate its performance. With 20 real-world troubleshooting cases, PeerPressure can effectively pinpoint the root-cause misconfigurations for 12 of these cases. For the remaining cases, PeerPressure significantly narrows down the number of root-cause candidates by three orders of magnitude. 1

Helen J. Wang; John C. Platt; Yu Chen; Ruyun Zhang; Yi-min Wang

2004-01-01T23:59:59.000Z

417

Pressure balance at the magnetopause: Experimental studies  

E-Print Network (OSTI)

The pressure balance at the magnetopause is formed by magnetic field and plasma in the magnetosheath, on one side, and inside the magnetosphere, on the other side. In the approach of dipole earth's magnetic field configuration and gas-dynamics solar wind flowing around the magnetosphere, the pressure balance predicts that the magnetopause distance R depends on solar wind dynamic pressure Pd as a power low R ~ Pd^alpha, where the exponent alpha=-1/6. In the real magnetosphere the magnetic filed is contributed by additional sources: Chapman-Ferraro current system, field-aligned currents, tail current, and storm-time ring current. Net contribution of those sources depends on particular magnetospheric region and varies with solar wind conditions and geomagnetic activity. As a result, the parameters of pressure balance, including power index alpha, depend on both the local position at the magnetopause and geomagnetic activity. In addition, the pressure balance can be affected by a non-linear transfer of the solar ...

Suvorova, A V

2011-01-01T23:59:59.000Z

418

PRESSURIZER ANALYSIS AND THE PRE DIGITAL PROGRAM  

SciTech Connect

An analysis is given which was programmed for the Philco 2000 (TRANSAC) Computer in order to provide a means for making pressurizer design and performance calculations. The analysis and digital program provide the exibility for studying the effects of various assumptions such as the type of steam compression process (i.e., isentropic or saturation), spray efficiency, wall condensation, and mixing of the pressurizer water and of the insurge. Also included in the program are data on pressure controlled steam and water relief,valves (total of four), pressure controlled heaters (total of five), pressure controlled spray valve, and various input formats allowing the use of either total surge, surge rate or bulk average temperature for the surge, spray fraction or spray rate for the spray and either temperatures or enthalpies for the surge and spray energies. The program uses steam and water properties in the form of empirical equations where the empirical constants in these equations may be changed depending upon the range of interest of the problem. (auth)

Findlay, J.A.

1961-07-14T23:59:59.000Z

419

Effect of hydrostatic pressure on the ambient pressure superconductor CePt3Si  

E-Print Network (OSTI)

We studied the evolution of superconductivity (sc) and antiferromagnetism (afm) in the heavy fermion compound CePt3Si with hydrostatic pressure. We present a pressure-temperature phase diagram established by electrical transport measurements. Pressure shifts the superconducting transition temperature, Tc, to lower temperatures. Antiferromagnetism is suppressed at a critical pressure Pc ? 0.5 GPa. Key words: CePt3Si, superconductivity, antiferromagnetism, hydrostatic pressure Superconductivity (sc) is one of the most striking effects in solid state physics. In a conventional superconductor Cooper pairing is mediated by phonons. In general, magnetism destroys superconductivity. In heavy fermion systems, however, sc exists in close proximity to magnetism, promoting the suspicion that the sc is mediated by magnetic excitations. Since the discovery of sc in the heavy fermion compound CeCu2Si2 at atmospheric pressure [1], only a few Ce-based systems were found which also exhibit sc at atmospheric pressure, like CeMIn5 (M=Co, Ir) [4]. Most superconducting pure Ce-based systems show sc only under applied pressure sufficient to suppress long range magnetic order, like CeIn3 [2] or CeRh2Si2 [3]. CeIn3 displays a typical temperature-pressure phase diagram for these compounds; antiferromagnetism (afm) is suppressed to zero temperature with pressure and sc develops right in the vicinity where afm disappears [2]. Very recently another material, namely CePt3Si, was found showing magnetic order and sc at atmospheric pressure [5]. In contrast to the systems mentioned before, the crystal

M. Nicklas A

2004-01-01T23:59:59.000Z

420

Variably insulating portable heater/cooler  

DOE Patents (OSTI)

A compact vacuum insulation panel is described comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning ``on`` and ``off`` the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls. 25 figs.

Potter, T.F.

1998-09-29T23:59:59.000Z

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


421

IS ACTIVE REGION CORE VARIABILITY AGE DEPENDENT?  

Science Conference Proceedings (OSTI)

The presence of both steady and transient loops in active region cores has been reported from soft X-ray and extreme-ultraviolet observations of the solar corona. The relationship between the different loop populations, however, remains an open question. We present an investigation of the short-term variability of loops in the core of two active regions in the context of their long-term evolution. We take advantage of the nearly full Sun observations of STEREO and Solar Dynamics Observatory spacecraft to track these active regions as they rotate around the Sun multiple times. We then diagnose the variability of the active region cores at several instances of their lifetime using EIS/Hinode spectral capabilities. We inspect a broad range of temperatures, including for the first time spatially and temporally resolved images of Ca XIV and Ca XV lines. We find that the active region cores become fainter and steadier with time. The significant emission measure at high temperatures that is not correlated with a comparable increase at low temperatures suggests that high-frequency heating is viable. The presence, however, during the early stages, of an enhanced emission measure in the ''hot'' (3.0-4.5 MK) and ''cool'' (0.6-0.9 MK) components suggests that low-frequency heating also plays a significant role. Our results explain why there have been recent studies supporting both heating scenarios.

Ugarte-Urra, Ignacio [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States); Warren, Harry P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)

2012-12-10T23:59:59.000Z

422

Variable temperature seat climate control system  

DOE Patents (OSTI)

A temperature climate control system comprises a variable temperature seat, at least one heat pump, at least one heat pump temperature sensor, and a controller. Each heat pump comprises a number of Peltier thermoelectric modules for temperature conditioning the air in a main heat exchanger and a main exchanger fan for passing the conditioned air from the main exchanger to the variable temperature seat. The Peltier modules and each main fan may be manually adjusted via a control switch or a control signal. Additionally, the temperature climate control system may comprise a number of additional temperature sensors to monitor the temperature of the ambient air surrounding the occupant as well as the temperature of the conditioned air directed to the occupant. The controller is configured to automatically regulate the operation of the Peltier modules and/or each main fan according to a temperature climate control logic designed both to maximize occupant comfort during normal operation, and minimize possible equipment damage, occupant discomfort, or occupant injury in the event of a heat pump malfunction.

Karunasiri, Tissa R. (Van Nuys, CA); Gallup, David F. (Pasadena, CA); Noles, David R. (Glendale, CA); Gregory, Christian T. (Alhambra, CA)

1997-05-06T23:59:59.000Z

423

Variably insulating portable heater/cooler  

DOE Green Energy (OSTI)

A compact vacuum insulation panel comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning "on" and "off" the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls.

Potter, Thomas F. (Denver, CO)

1998-01-01T23:59:59.000Z

424

SLUDGE BATCH VARIABILITY STUDY WITH FRIT 418  

SciTech Connect

The Defense Waste Processing Facility (DWPF) initiated processing Sludge Batch 6 (SB6) in the summer of 2010. In support of processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frit 418 to process SB6. This recommendation was based on assessments of the compositional projections for SB6 available at the time from the Liquid Waste Organization (LWO) and SRNL (using a model-based approach). To support qualification of SB6, SRNL executed a variability study to assess the applicability of the current durability models for SB6. The durability models were assessed over the expected Frit 418-SB6 composition range. Seventeen glasses were selected for the variability study based on the sludge projections used in the frit recommendation. Five of the glasses are based on the centroid of the compositional region, spanning a waste loading (WL) range of 32 to 40%. The remaining twelve glasses are extreme vertices (EVs) of the sludge region of interest for SB6 combined with Frit 418 and are all at 36% WL. These glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). After initiating the SB6 variability study, the measured composition of the SB6 Tank 51 qualification glass produced at the SRNL Shielded Cells Facility indicated that thorium was present in the glass at an appreciable concentration (1.03 wt%), which made it a reportable element for SB6. This concentration of ThO{sub 2} resulted in a second phase of experimental studies. Five glasses were formulated that were based on the centroid of the new sludge compositional region combined with Frit 418, spanning a WL range of 32 to 40%. These glasses were fabricated and characterized using chemical composition analysis and the PCT. Based on the measured PCT response, all of the glasses (with and without thorium) were acceptable with respect to the Environmental Assessment (EA) reference glass regardless of thermal history. All of the normalized boron releases were less than 1 g/L. While all of the targeted glass compositions were predictable with respect to the Product Composition Control System (PCCS) models for durability, a small number of the measured glass compositions were located outside of the lower prediction limit indicating poorer durability than what was actually measured. These unpredictable glasses were in the same lithium metaborate (LM) preparation block during the chemical analyses, which resulted in measured compositions that were not representative of the target compositions. A review of the data did not indicate a clear cause for the problem. Re-digestion and re-measurement of three glasses from this preparation block yielded glass compositions closer to the target values and predicted PCT responses within the PCCS model uncertainty. Therefore, it is believed that the glasses were correctly fabricated and the targeted compositions are closer representations of the true compositions. Per the requirements of the DWPF Glass Product Control Program, the PCCS durability models have been shown to be applicable for the SB6/Frit 418 glass system. PCT results from the glasses fabricated as part of the variability study were shown to be predictable and/or acceptable with respect to the DWPF PCCS models. In addition, the inclusion of ThO{sub 2} was shown to have minimal impact on the acceptability and predictability of the variability study glasses.

Johnson, F.; Edwards, T.

2010-11-29T23:59:59.000Z

425

Atmospheric Pressure Plasma Process And Applications  

SciTech Connect

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.

Peter C. Kong; Myrtle

2006-09-01T23:59:59.000Z

426

Pressure balanced drag turbine mass flow meter  

DOE Patents (OSTI)

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.

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

1982-01-01T23:59:59.000Z

427

Pressure balanced drag turbine mass flow meter  

DOE Patents (OSTI)

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.

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

1980-04-23T23:59:59.000Z

428

Pressure-activated well perforating apparatus  

Science Conference Proceedings (OSTI)

A well perforating technique utilizes a predetermined pressure difference developed at different points in the borehole to actuate the firing mechanism of a tubing conveyed perforating gun. A first embodiment incorporated as part of a well test string includes a packer for isolating a wellbore interval and a perforating gun connected in the string below the packer which is fired in response to development of a greater pressure in the annulus above the packer than in the isolated interval, thereby causing perforation at ''underbalanced'' conditions. A modified ''full-bore'' embodiment has an annular configuration firing mechanism as part of a tubing string and fires the perforating gun in response to development of a predetermined difference between the pressures at a point in the annulus and a point in the central bore of the tubing string.

Upchurch, J. M.

1985-12-24T23:59:59.000Z

429

High pressure electrical insulated feed thru connector  

DOE Patents (OSTI)

A feed-thru type hermetic electrical connector including at least one connector pin feeding through an insulator block within the metallic body of the connector shell. A compression stop arrangement coaxially disposed about the insulator body is brazed to the shell, and the shoulder on the insulator block bears against this top in a compression mode, the high pressure or internal connector being at the opposite end of the shell. Seals between the pin and an internal bore at the high pressure end of the insulator block and between the insulator block and the metallic shell at the high pressure end are hermetically brazed in place, the first of these also functioning to transfer the axial compressive load without permitting appreciable shear action between the pin and insulator block.

Oeschger, Joseph E. (Palo Alto, CA); Berkeland, James E. (San Jose, CA)

1979-11-13T23:59:59.000Z

430

Nuclear Power Plant Containment Pressure Boundary Research  

SciTech Connect

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.

Cherry, J.L.; Chokshi, N.C.; Costello, J.F.; Ellingwood, B.R.; Naus, D.J.

1999-09-15T23:59:59.000Z

431

Variability of the Somali Current as Observed from Seasat Altimetry  

Science Conference Proceedings (OSTI)

Three methods of extraction of mesoscale variability from altimetry are compared in the Somali current area: crossover residuals after minimization to reduce orbit errors, along-track variability using quasi-repetitive tracks, and difference ...

C. Perigaud; J. F. Minster

1988-01-01T23:59:59.000Z

432

U-090: RSA enVision Discloses Environment Variable Information...  

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

0: RSA enVision Discloses Environment Variable Information to Remote Users U-090: RSA enVision Discloses Environment Variable Information to Remote Users January 27, 2012 - 6:00am...

433

Stochastic Forcing of Ocean Variability by the North Atlantic Oscillation  

Science Conference Proceedings (OSTI)

At middle and high latitudes, the magnitude of stochastic wind stress forcing of the ocean by atmospheric variability on synoptic time scales (i.e., “weather” related variability) is comparable to that of the seasonal cycle. Stochastic forcing ...

Kettyah C. Chhak; Andrew M. Moore; Ralph F. Milliff

2009-01-01T23:59:59.000Z

434

Spatial Variability of Shortwave Irradiance for Snowmelt in Forests  

Science Conference Proceedings (OSTI)

The spatial variation of melt energy can influence snow cover depletion rates and in turn be influenced by the spatial variability of shortwave irradiance to snow. The spatial variability of shortwave irradiance during melt under uniform and ...

John Pomeroy; Chad Ellis; Aled Rowlands; Richard Essery; Janet Hardy; Tim Link; Danny Marks; Jean Emmanuel Sicart

2008-12-01T23:59:59.000Z

435

West African Monsoon Intraseasonal Variability: A Precipitable Water Perspective  

Science Conference Proceedings (OSTI)

West African monsoon intraseasonal variability has important implications for food security and drought early warnings. In the present study, intraseasonal variability over the Sahel is assessed from the perspective of precipitable water, as ...

D. Emmanuel Poan; Romain Roehrig; Fleur Couvreux; Jean-Philippe Lafore

2013-04-01T23:59:59.000Z

436

Temporal Variability of Diapycnal Mixing in Shag Rocks Passage  

Science Conference Proceedings (OSTI)

Diapycnal mixing rates in the oceans have been shown to have a great deal of spatial variability, but the temporal variability has been little studied. Here results are presented from a method developed to calculate diapycnal diffusivity from ...

Gillian M. Damerell; Karen J. Heywood; David P. Stevens; Alberto C. Naveira Garabato

2012-03-01T23:59:59.000Z

437

Modeling the Variability of Sydney Harbor Wind Measurements  

Science Conference Proceedings (OSTI)

The time-dependent behavior in the variability of wind measurements is investigated using bivariate generalized autoregressive conditional heteroscedastic models. These models express the current level of short-timescale wind variability in terms ...

Edward Cripps; William T. M. Dunsmuir

2003-08-01T23:59:59.000Z

438

LPB Hydro-Climate Variability as Simulated by GCM Experiments...  

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

LPB Hydro-Climate Variability as Simulated by GCM Experiments: Role of Remote SST Forcing Title LPB Hydro-Climate Variability as Simulated by GCM Experiments: Role of Remote SST...

439

Snowpack spatial variability: towards understanding its effect on remote sensing  

E-Print Network (OSTI)

Snowpack spatial variability: towards understanding its effect on remote sensing measurements spatial variability: towards understanding its effect on remote sensing mea- surements and snow slope large errors in these basin estimates. Remote sensing measurements offer a promising alternative, due

Marshall, Hans-Peter

440

Jet Jumping: Low-Frequency Variability in the Southern Ocean  

Science Conference Proceedings (OSTI)

The authors study intrinsic variability in the position of jets in a ?-plane channel ocean with simple topography using a quasigeostrophic numerical model. This study links the variability in jet position with abyssal anticyclones that form as a ...

Christopher C. Chapman; Andrew McC. Hogg

2013-05-01T23:59:59.000Z

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


441

Modeling Climate Variability in the Tropical Atlantic Atmosphere  

Science Conference Proceedings (OSTI)

Climate variability in the tropical Atlantic sector as represented in six atmospheric general circulation models is examined. On the annual mean, most simulations overestimate wind stress away from the equator although much of the variability can ...

Jiande Wang; James A. Carton

2003-12-01T23:59:59.000Z

442

Intraseasonal Variability over Tropical Africa during Northern Summer  

Science Conference Proceedings (OSTI)

The intraseasonal variability over Africa during northern summer was analyzed, using 25 years of NCEP– NCAR reanalysis and satellite data. The dominant pattern of variability was one of enhanced deep convection over the whole African monsoon ...

Adrian J. Matthews

2004-06-01T23:59:59.000Z

443

Tropical Cloud Feedbacks and Natural Variability of Climate  

Science Conference Proceedings (OSTI)

Simulations of natural variability by two GCMs are examined. One GCM is a sector model, allowing relatively rapid integration without simplification of the model physics, which would potentially exclude mechanisms of variability. Two mechanisms ...

R. L. Miller; A. D. Del Genio

1994-09-01T23:59:59.000Z

444

A search for chaotic behavior in Northern Hemisphere stratospheric variability  

Science Conference Proceedings (OSTI)

Northern Hemisphere stratospheric variability is investigated with respect to chaotic behavior using time series from three different variables extracted from four different re-analysis products and two numerical model runs with different forcing. ...

Gualtiero Badin; Daniela I.V. Domeisen

445

Role of Smarter Grids in Variable Renewable Resource Integration (Presentation)  

Science Conference Proceedings (OSTI)

This presentation discusses the role of smarter grids in variable renewable resource integration and references material from a forthcoming ISGAN issue paper: Smart Grid Contributions to Variable Renewable Resource Integration, co-written by the presenter and currently in review.

Miller, M.

2012-07-01T23:59:59.000Z

446

Turbine power plant with back pressure turbine  

SciTech Connect

A combined gas/steam turbine power plant is disclosed including a gas turbine having a combustion chamber and a steam turbine driven by steam generated with heat from the combustion gases of the gas turbine. The steam is utilized in a technological process downstream of the steam turbine. Relatively small fluctuations in back pressure are compensated by varying a delivery of fuel to the combustion chamber. Relatively large fluctuations in back pressure are compensated by supplying live steam directly to the technological process downstream of the steam turbine. Various devices are provided for conditioning the steam prior to being supplied to the technological process.

Kalt, J.; Kehlhofer, R.

1981-06-23T23:59:59.000Z

447

Hydrogen at high pressure and temperatures  

DOE Green Energy (OSTI)

Hydrogen at high pressures and temperatures is challenging scientifically and has many real and potential applications. Minimum metallic conductivity of fluid hydrogen is observed at 140 GPa and 2600 K, based on electrical conductivity measurements to 180 GPa (1.8 Mbar), tenfold compression, and 3000 K obtained dynamically with a two-stage light-gas gun. Conditions up to 300 GPa, sixfold compression, and 30,000 K have been achieved in laser-driven Hugoniot experiments. Implications of these results for the interior of Jupiter, inertial confinement fusion, and possible uses of metastable solid hydrogen, if the metallic fluid could be quenched from high pressure, are discussed.

Nellis, W J

1999-09-30T23:59:59.000Z

448

Atmospheric Pressure Deposition for Electrochromic Windows  

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

Atmospheric Pressure Deposition Atmospheric Pressure Deposition for Electrochromic Windows TDM - Karma Sawyer Robert C. Tenent National Renewable Energy Laboratory robert.tenent@nrel.gov 303-384-6775 4/4/2013 Insulating Glass Unit (IGU) Glass Transparent Conductor (TC) Active Electrode Counter Electrode Ion Conductor 2 | Building Technologies Office eere.energy.gov Purpose and Objectives * Expense - Current market price of $50-$100/ft 2 - Projections indicate under $20/ft 2 needed - A new production paradigm is required * Aesthetics - Architects hesitant to adopt "smurf glass"

449

High-Pressure Tube Trailers and Tanks  

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

Berry Berry Salvador M. Aceves Lawrence Livermore National Laboratory (925) 422-0864 saceves@LLNL.GOV DOE Delivery Tech Team Presentation Chicago, Illinois February 8, 2005 Inexpensive delivery of compressed hydrogen with ambient temperature or cryogenic compatible vessels * Pressure vessel research at LLNL Conformable (continuous fiber and replicants) Cryo-compressed * Overview of delivery options * The thermodynamics of compressed and cryo-compressed hydrogen storage * Proposed analysis activities * Conclusions Outline We are investigating two techniques for reduced bending stress: continuous fiber vessels and vessels made of replicants Conformable tanks require internal stiffeners (ribs) to efficiently support the pressure and minimize bending stresses Spherical and cylindrical tanks

450

Atmospheric Pressure Deposition for Electrochromic Windows  

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

Atmospheric Pressure Deposition Atmospheric Pressure Deposition for Electrochromic Windows TDM - Karma Sawyer Robert C. Tenent National Renewable Energy Laboratory robert.tenent@nrel.gov 303-384-6775 4/4/2013 Insulating Glass Unit (IGU) Glass Transparent Conductor (TC) Active Electrode Counter Electrode Ion Conductor 2 | Building Technologies Office eere.energy.gov Purpose and Objectives * Expense - Current market price of $50-$100/ft 2 - Projections indicate under $20/ft 2 needed - A new production paradigm is required * Aesthetics - Architects hesitant to adopt "smurf glass"

451

High pressure water jet mining machine  

DOE Patents (OSTI)

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.

Barker, Clark R. (Rolla, MO)

1981-05-05T23:59:59.000Z

452

Pressure on the well servicing market  

Science Conference Proceedings (OSTI)

While the well servicing and workover (ws/wo) market is extremely strong and is expected to grow even stronger in the foreseeable future, several pressures are affecting the overall market. These pressures include (1) uncertainty about crude oil prices that is forcing operators to reconsider some marginal ws/wo prospects; (2) demand for oil and gas in future periods; (3) effect of current rate of rig building; and (4) changing requirements of producers. This discussion evaluates the probable effects of possible changes in each of these areas.

Haynes, J.P.

1981-10-01T23:59:59.000Z

453

Holographic Dark Energy Scenario and Variable Modified Chaplygin Gas  

E-Print Network (OSTI)

In this letter, we have considered that the universe is filled with normal matter and variable modified Chaplygin gas. Also we have considered the interaction between normal matter and variable modified Chaplygin gas in FRW universe. Then we have considered a correspondence between the holographic dark energy density and interacting variable modified Chaplygin gas energy density. Then we have reconstructed the potential of the scalar field which describes the variable modified Chaplygin cosmology.

Surajit Chattopadhyay; Ujjal Debnath

2009-01-15T23:59:59.000Z

454

Bayesian Variable Selection and the Swendsen-Wang Algorithm  

E-Print Network (OSTI)

Bayesian Variable Selection and the Swendsen-Wang Algorithm David J. NOTT and Peter J. GREEN improvements in Markov chain Monte Carlo sampling algorithms for Bayesian variable selection. Currently used, this excludes the ith predictor from the model. The problem of variable selection is to decide which predictors

Green, Peter

455

Bayesian variable selection and the Swendsen-Wang algorithm  

E-Print Network (OSTI)

Bayesian variable selection and the Swendsen-Wang algorithm David J. Nott1 and Peter J. Green2 1 motivated improvements in Markov chain Monte Carlo sampling algorithms for Bayesian variable selection. Traditional sampling al- gorithms for Bayesian variable selection may perform poorly when there are severe

Barber, Stuart

456

The TAOS Project Stellar Variability II. Detection of 15 Variable Stars  

SciTech Connect

The Taiwanese-American Occultation Survey (TAOS) project has collected more than a billion photometric measurements since 2005 January. These sky survey data - covering timescales from a fraction of a second to a few hundred days - are a useful source to study stellar variability. A total of 167 star fields, mostly along the ecliptic plane, have been selected for photometric monitoring with the TAOS telescopes. This paper presents our initial analysis of a search for periodic variable stars from the time-series TAOS data on one particular TAOS field, No. 151 (RA = 17{sup h} 30{sup m} 6.67{sup s}, Dec = 27 degrees, 17 minutes, 30 seconds, J2000), which had been observed over 47 epochs in 2005. A total of 81 candidate variables are identified in the 3 square degree field, with magnitudes in the range 8 < R < 16. On the basis of the periodicity and shape of the lightcurves, 32 variables, 18 of which were previously unknown, are classified as RR Lyrae, Cepheid, {delta} Scuti, SX Phonencis, semi-regular and eclipsing binaries.

Mondal, S; Lin, C C; Zhang, Z W; Alcock, C; Axelrod, T; Bianco, F B; Byun, Y I; Coehlo, N K; Cook, K H; Dave, R; Kim, D W; King, S K; Lee, T; Lehner, M J; Lin, H C; Marshall, S L; Protopapas, P; Rice, J A; Schwamb, M E; Wang, J H; Wang, S Y; Wen, C Y

2010-01-28T23:59:59.000Z

457

Stochastic variability of effective properties via the generalized variability response function  

Science Conference Proceedings (OSTI)

Homogenization of randomly heterogeneous material properties into effective properties is an essential procedure in facilitating the analysis of a wide range of mechanics problems. Although formulas exist to calculate deterministic effective properties ... Keywords: Effective properties, Random fields, Uncertainty quantification, Variability response functions

Kirubel Teferra; Sanjay R. Arwade; George Deodatis

2012-11-01T23:59:59.000Z

458

Characterisation of soil texture variability using the apparent soil electrical conductivity at a highly variable site  

Science Conference Proceedings (OSTI)

The characterisation of the spatial distribution of clay, silt, and sand/gravel is one of the main objectives of soil surveys. Researchers as well as producers have an interest in characterising soil texture variability. The objective of our study was ... Keywords: Clay, EM38, Residual kriging, Sand/gravel, Silt, Spatial heterogeneity

K. Heil; U. Schmidhalter

2012-02-01T23:59:59.000Z

459

Continuous variable tangle, monogamy inequality, and entanglement sharing in Gaussian states of continuous variable systems  

E-Print Network (OSTI)

For continuous-variable systems, we introduce a measure of entanglement, the continuous variable tangle ({\\em contangle}), with the purpose of quantifying the distributed (shared) entanglement in multimode, multipartite Gaussian states. This is achieved by a proper convex roof extension of the squared logarithmic negativity. We prove that the contangle satisfies the Coffman-Kundu-Wootters monogamy inequality in all three--mode Gaussian states, and in all fully symmetric $N$--mode Gaussian states, for arbitrary $N$. For three--mode pure states we prove that the residual entanglement is a genuine tripartite entanglement monotone under Gaussian local operations and classical communication. We show that pure, symmetric three--mode Gaussian states allow a promiscuous entanglement sharing, having both maximum tripartite residual entanglement and maximum couplewise entanglement between any pair of modes. These states are thus simultaneous continuous-variable analogs of both the GHZ and the $W$ states of three qubits: in continuous-variable systems monogamy does not prevent promiscuity, and the inequivalence between different classes of maximally entangled states, holding for systems of three or more qubits, is removed.

Gerardo Adesso; Fabrizio Illuminati

2004-10-06T23:59:59.000Z

460

Quantifying decoherence in continuous variable systems  

E-Print Network (OSTI)

We present a detailed report on the decoherence of quantum states of continuous variable systems under the action of a quantum optical master equation resulting from the interaction with general Gaussian uncorrelated environments. The rate of decoherence is quantified by relating it to the decay rates of various, complementary measures of the quantum nature of a state, such as the purity, some nonclassicality indicators in phase space and, for two-mode states, entanglement measures and total correlations between the modes. Different sets of physically relevant initial configurations are considered, including one- and two-mode Gaussian states, number states, and coherent superpositions. Our analysis shows that, generally, the use of initially squeezed configurations does not help to preserve the coherence of Gaussian states, whereas it can be effective in protecting coherent superpositions of both number states and Gaussian wave packets. 1

A. Serafini; M. G. A. Paris; F. Illuminati; S. De Siena

2005-01-01T23:59:59.000Z

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While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Variational estimates using a discrete variable representation  

SciTech Connect

The advantage of using a discrete variable representation (DVR) is that the Hamiltonian of two interacting particles can be constructed in a very simple form. However, the DVR Hamiltonian is approximate and, as a consequence, the results cannot be considered as variational ones. We will show that the variational character of the results can be restored by performing a reduced number of integrals. In practice, for a variational description of the lowest n bound states only n(n+1)/2 integrals are necessary whereas D(D+1)/2 integrals are enough for the scattering states (D is the dimension of the S matrix). Applications of the method to the study of dimers of He, Ne and Ar, for both bound and scattering states, are presented.

Lombardi, M.; Barletta, P.; Kievsky, A. [Istituto Nazionale di Fisica Nucleare, Via Buonarroti 2, 56100 Pisa (Italy); Dipartimento di Fisica, Universita di Pisa, 56100 Pisa (Italy)

2004-09-01T23:59:59.000Z

462

Variable selection in nonparametric additive models  

E-Print Network (OSTI)

We consider a nonparametric additive model of a conditional mean function in which the number of variables and additive components may be larger than the sample size but the number of nonzero additive components is "small" relative to the sample size. The statistical problem is to determine which additive components are nonzero. The additive components are approximated by truncated series expansions with B-spline bases. With this approximation, the problem of component selection becomes that of selecting the groups of coefficients in the expansion. We apply the adaptive group Lasso to select nonzero components, using the group Lasso to obtain an initial estimator and reduce the dimension of the problem. We give conditions under which the group Lasso selects a model whose number of components is comparable with the underlying model, and the adaptive group Lasso selects the nonzero components correctly with probability approaching one as the sample size increases and achieves the optimal rate of convergence. Th...

Huang, Jian; Wei, Fengrong; 10.1214/09-AOS781

2010-01-01T23:59:59.000Z

463

Forecasting neutron star temperatures: predictability and variability  

E-Print Network (OSTI)

It is now possible to model thermal relaxation of neutron stars after bouts of accretion during which the star is heated out of equilibrium by nuclear reactions in its crust. Major uncertainties in these models can be encapsulated in modest variations of a handful of fudge parameters that change the crustal thermal conductivity, specific heat, and heating rates. Observations of thermal relaxation constrain these fudge parameters and allow us to predict longer term variability in terms of the neutron star core temperature. We demonstrate this explicitly by modeling ongoing thermal relaxation in the neutron star XTE J1701-462. Its future cooling, over the next 5 to 30 years, is strongly constrained and depends mostly on its core temperature, uncertainties in crust physics having essentially been pinned down by fitting to the first three years of observations.

Dany Page; Sanjay Reddy

2013-07-17T23:59:59.000Z

464

Variable Interactions in Query-Driven Visualization  

SciTech Connect

One fundamental element of scientific inquiry is discoveringrelationships, particularly the interactions between different variablesin observed or simulated phenomena. Building upon our prior work in thefield of Query-Driven Visualization, where visual data analysisprocessing is focused on subsets of large data deemed to be"scientifically interesting," this new work focuses on a novel knowledgediscovery capability suitable for use with petascale class datasets. Itenables visual presentation of the presence or absence of relationships(correlations) between variables in data subsets produced by Query-Drivenmethodologies. This technique holds great potential for enablingknowledge discovery from large and complex datasets currently emergingfrom SciDAC and INCITE projects. It is sufficiently generally to beapplicable to any time of complex, time-varying, multivariate data fromstructured, unstructured or adaptive grids.

Bethel, E. Wes; Gosink, Luke J.; Anderson, John C.; Joy, Kenneth I.

2007-10-25T23:59:59.000Z

465

Quantifying decoherence in continuous variable systems  

E-Print Network (OSTI)

We present a detailed report on the decoherence of quantum states of continuous variable systems under the action of a quantum optical master equation resulting from the interaction with general Gaussian uncorrelated environments. The rate of decoherence is quantified by relating it to the decay rates of various, complementary measures of the quantum nature of a state, such as the purity, some nonclassicality indicators in phase space and, for two-mode states, entanglement measures and total correlations between the modes. Different sets of physically relevant initial configurations are considered, including one- and two-mode Gaussian states, number states, and coherent superpositions. Our analysis shows that, generally, the use of initially squeezed configurations does not help to preserve the coherence of Gaussian states, whereas it can be effective in protecting coherent superpositions of both number states and Gaussian wave packets.

A. Serafini; M. G. A. Paris; F. Illuminati; S. De Siena

2005-01-28T23:59:59.000Z

466

Gravity-Capillary Lumps Generated by a Moving Pressure Source  

E-Print Network (OSTI)

The nonlinear wave pattern generated by a localized pressure source moving over a liquid free surface

Diorio, James

467

Parametric System Curves: Correlations Between Fan Pressure Rise and Flow for Large Commercial Buildings  

SciTech Connect

A substantial fraction of HVAC energy use in large commercial buildings is due to fan operation. Fan energy use depends in part on the relationship between system pressure drop and flow through the fan, which is commonly called a "system curve." As a step toward enabling better selections of air-handling system components and analyses of common energy efficiency measures such as duct static pressure reset and duct leakage sealing, this paper shows that a simple four-parameter physical model can be used to define system curves. Our model depends on the square of the fan flow, as is commonly considered. It also includes terms that account for linear-like flow resistances such as filters and coils, and for supply duct leakage when damper positions are fixed or are changed independently of static pressure or fan flow. Only two parameters are needed for systems with variable-position supply dampers (e.g., VAV box dampers modulating to control flow). For these systems, reducing or eliminating supply duct leakage does not change the system curve. The parametric system curve may be most useful when applied to field data. Non-linear techniques could be used to fit the curve to fan pressure rise and flow measurements over a range of operating conditions. During design, when measurements are unavailable, one could use duct design calculation tools instead to determine the coefficients.

Sherman, Max; Wray, Craig

2010-05-19T23:59:59.000Z

468

Corrosion of Low Pressure Steam Turbine Components  

Science Conference Proceedings (OSTI)

Most outage hours for steam turbines are due to corrosion of low pressure (LP) blades and disks in the phase transition zone (PTZ). The development of an effective localized corrosion damage prediction technology is essential for the successful avoidance of unscheduled outages of steam

2000-11-28T23:59:59.000Z

469

Reconstruction of Pressure Profile Evolution during  

E-Print Network (OSTI)

of plasma current and plasma pressure profiles from external measurements of the equilibrium magnetic field currents, eddy currents flowing in the vacuum vessel, constant magnetic flux linking the superconductor, and new flux loops located near the hot plasma in order to closely couple to plasma current and dipole

470

Pressure-shear experiments on granular materials.  

SciTech Connect

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.

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

471

Notes 11. High pressure floating ring seals  

E-Print Network (OSTI)

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 coefficients, effect on rotor stability, recommendations for grooved seals with reduced leakage and lesser cross-stiffnesses.

San Andres, Luis

2009-01-01T23:59:59.000Z

472

Reactor pressure vessel with forged nozzles  

DOE Patents (OSTI)

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.

Desai, Dilip R. (Fremont, CA)

1993-01-01T23:59:59.000Z

473

Compensated vibrating optical fiber pressure measuring device  

SciTech Connect

A microbending optical fiber is attached under tension to a diaphragm to se a differential pressure applied across the diaphragm which it causes it to deflect. The fiber is attached to the diaphragm so that one portion of the fiber, attached to a central portion of the diaphragm, undergoes a change in tension; proportional to the differential pressure applied to the diaphragm while a second portion attached at the periphery of the diaphragm remains at a reference tension. Both portions of the fiber are caused to vibrate at their natural frequencies. Light transmitted through the fiber is attenuated by both portions of the tensioned sections of the fiber by an amount which increases with the curvature of fiber bending so that the light signal is modulated by both portions of the fiber at separate frequencies. The modulated light signal is transduced into a electrical signal. The separate modulation signals are detected to generate separate signals having frequencies corresponding to the reference and measuring vibrating sections of the continuous fiber, respectively. A signal proportional to the difference between these signals is generated which is indicative of the measured pressure differential across the diaphragm. The reference portion of the fiber is used to compensate the pressure signal for zero and span changes resulting from ambient temperature and humidity effects upon the fiber and the transducer fixture.

Fasching, George E. (Morgantown, WV); Goff, David R. (Christiansburg, VA)

1987-01-01T23:59:59.000Z

474

Vlasov fluid model with electron pressure  

SciTech Connect

The Vlasov-ion, fluid-electron model of Freidberg for studying the linear stability of hot-ion pinch configurations is here extended to include electron pressure. Within the framework of an adiabatic electron-gas picture, it is shown that this model is still amenable to the numerical methods described by Lewis and Freidberg. (auth)

Gerwin, R.

1975-11-01T23:59:59.000Z

475

Polynomial Fits to Saturation Vapor Pressure  

Science Conference Proceedings (OSTI)

The authors describe eighth- and sixth-order polynomial fits to Wexler's and Hyland-Wexler's saturation-vapor-pressure expressions. Fits are provided in both least-squares and relative-error norms. Error analysis is presented. The authors show ...

Piotr J. Flatau; Robert L. Walko; William R. Cotton

1992-12-01T23:59:59.000Z

476

Constant-Pressure Measurement of Steam-  

E-Print Network (OSTI)

SGP-TR-169 Constant-Pressure Measurement of Steam- Water Relative Permeability Peter A. O by measuring in-situ steam saturation more directly. Mobile steam mass fraction was established by separate steam and water inlets or by correlating with previous results. The measured steam-water relative

Stanford University

477

System for throttling and compensation for variable feedstock properties  

DOE Patents (OSTI)

Apparatus is shown for adjusting the feed rate of pulverized feed material into a pressurized container. The apparatus also has utility for compensating for variations in the permeability of the feed material. A rotor that includes sprues with provision for controlling the pressure distribution along the sprues is located within the pressurized container. The rotor hub is connected to a drive means and a material supply means which extend through the wall of the container. A line for controlling pressure along the sprues by gas injection is connected to a chamber between sections of the sprue for controlling gas pressure at that point. The gas pressure control line is connected to a pressurized gas source and a control system external to the rotor.

Meyer, John W. (Palo Alto, CA)

1981-01-01T23:59:59.000Z

478

Sequence of surface meteorological variables with the passage of winter cold fronts in the United States east of the Rocky Mountains  

E-Print Network (OSTI)

According to the 80-year-old Norwegian cyclone model, fronts are pressure troughs, extensions of a mid-latitude cyclone. Thus, a cold frontal passage is evidenced at the surface by a minimum in air pressure and a corresponding wind shift. In addition, decreases in both temperature and humidity also occur. This conceptual model assumes that these changes are nearly coincident in time; however, this is usually not the case. Strict adherence to the model is the basis for the highly subjective single line drawn on a synoptic chart to indicate a front. To evaluate the behavior of meteorological variables with cold frontal passage, data was collected for seven American cities east of the Rocky Mountains, including NMC/NCEP 3-hourly surface analyses and NCDC archived hourly surface observations during three consecutive winters (October 1-March 31). Surface analyses were used to estimate the time of frontal passage. Using these estimates as a guide, the hourly observations were employed to determine the specific hours at which each meteorological variable demonstrated a change that could be conclusively attributed to the frontal passage. The four meteorological variables scrutinized include temperature, moisture (dew point), wind (direction), and pressure. Significance of means tests were applied to assess the statistical significance of the differences between the timing of each pair of variables (temperature vs. wind, dew point vs. pressure, etc.). Statistically significant differences mathematically validate the sequence of the means and suggest the likely repeatability of the sequence. At all locations and for all subsets of fronts, the pressure rise and the wind shift consistently precede the decreases in temperature and dew point. The timing of the pressure rise, however, is nearly indistinguishable from the wind shift, and likewise, there is rarely any significant difference between the decrease in temperature and the decrease in dew point. While all the variables are essentially coincident in time for some fronts, there is a frequent disparity between the pressure rise/wind shift and the temperature/dew point decrease. The data thus suggest a double-boundary frontal zone, a surface pressure trough/wind shift line followed by a temperature/moisture boundary.

Huckaby, Daniel Dale

2001-01-01T23:59:59.000Z

479

Fuel Cell Technologies Office: International Hydrogen Fuel and Pressure  

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

International Hydrogen International Hydrogen Fuel and Pressure Vessel Forum to someone by E-mail Share Fuel Cell Technologies Office: International Hydrogen Fuel and Pressure Vessel Forum on Facebook Tweet about Fuel Cell Technologies Office: International Hydrogen Fuel and Pressure Vessel Forum on Twitter Bookmark Fuel Cell Technologies Office: International Hydrogen Fuel and Pressure Vessel Forum on Google Bookmark Fuel Cell Technologies Office: International Hydrogen Fuel and Pressure Vessel Forum on Delicious Rank Fuel Cell Technologies Office: International Hydrogen Fuel and Pressure Vessel Forum on Digg Find More places to share Fuel Cell Technologies Office: International Hydrogen Fuel and Pressure Vessel Forum on AddThis.com... Publications Program Publications Technical Publications

480

Variable Stars in the Globular Cluster NGC 4590 (M68  

E-Print Network (OSTI)

We present results of time series photometry to search for variable stars in the field of metal-poor globular cluster NGC 4590 (M68). Periods have been revised for 40 known variables and no significant changes were found. A considerable change in Blazhko effect for V25 has been detected. Among nine newly discovered variable candidates, 5 stars are of RRc Bailey type variables while 4 stars are unclassified. The variable stars V10, V21, V50 and V51 are found to be cluster members based on the radial velocity data taken from literature.

Sariya, Devesh Path; Yadav, R K S

2013-01-01T23:59:59.000Z

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