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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

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

E-Print Network (OSTI)

a high-speed video system. A fast photo detector is used to measure the scaling of the cavitation fluc- tuations by measuring the light scattered from cavitating bubbles in a small region of the flowUsing cavitation to measure statistics of low-pressure events in large-Reynolds-number turbulence A

La Porta, Arthur

4

Cavitation erosion of silver plated coating at different temperatures and pressures  

SciTech Connect

Cavitation often occurs in inducer pumps used for space rockets. Silver plated coating on the inducer liner faces the damage of cavitation. Therefore, it is important to study about the cavitation erosion resistance for silver plated coating at several operating conditions in the inducer pumps. In this study, the cavitation erosion tests were carried for silver plated coating in deionized water and ethanol at several liquid temperatures (273K–400K) and pressures (0.10MPa–0.48MPa). The mass loss rate is evaluated in terms of thermodynamic parameter ? proposed by Brennen [9], suppression pressure p–p{sub v} (p{sub v}: saturated vapor pressure) and acoustic impedance ?c (?: density and c: sound speed). Cavitation bubble behaviors depending on the thermodynamic effect and the liquid type were observed by high speed video camera. The mass loss rate is formulated by thermodynamic parameter ?, suppression pressure p–p{sub v} and acoustic impedance ?c.

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

2014-04-11T23:59:59.000Z

5

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

E-Print Network (OSTI)

-vapor surface tension, if one phase is brought in the stability region of the other, it can be observed, to put the liquid under me- chanical tension. This allows us to study the nucleation of a bubble investigate the limiting mechanical tension negative pressure that liquid water can sustain before cavitation

Caupin, Frédéric

6

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

7

Variable pressure operation: An assessment  

SciTech Connect

This report summarizes the benefits, drawbacks, and technical issues of variable pressure operation (VPO) retrofit. Under VPO, turbine throttle pressure is reduced at low loads. This operating mode offers several significant advantages for units that cycle or operate at low loads for extended periods. Information used in the report was assembled from published sources, from major equipment manufacturers, and from utilities operating units under VPO in the US, Europe and Japan. The report also contains statistics of VPO use in this country and abroad. Design features of new units using VPO in Europe and Japan are presented to identify potential directions for future US designs incorporating VPO.

Kimel, E.; Kemeny, P.; Bierman, E.; Lagomarsino, J.; Clarke, D. (Burns and Roe, Inc., Oradell, NJ (USA))

1990-03-01T23:59:59.000Z

8

Computer simulations of cavitation collapses at high static pressure using hydrocode HYADES: Plasma conditions and shock waves in the liquid  

Science Journals Connector (OSTI)

Previously (JASA 121 pt.2 p. 3181) transient cavitation in high pressure spherical resonators was described. The phenomenon is characterized by cavitation events lasting a few ms (100 s acoustic cycles) in which a cavity (or cavities) collapse violently emitting flashes of light of widths ?1–40 nsec and spherical shock waves with amplitudes ?1–100 bars (depending on the static pressure) at a distance of 10 cm from the collapse. Both SL and shock amplitudes are proportional to the static pressure. The goal of these experiments is to investigate how the static pressure increases the intensity of acoustic cavitation collapse and whether thermonuclear fusion reactions are possible this way. The determination of plasma temperatures pressures and densities is therefore critical in making progress. Furthermore the amplitude and velocity of the shock waves can be used to determine the conditions at stagnation (end of collapse) assuming the cavity size at that time is known. To this end results of numerical simulations using HYADES plasma physics hydrocode will be presented with emphasis on the plasma conditions versus the amount of gas in the cavity and the static pressure as well as the amplitude and velocity of the outgoing shock waves generated after the collapse [Work supported by SMDC Contract No. W9113M?07?C?0178.

D. Felipe Gaitan; Ross A. Tessien; Robert A. Hiller; Jeff Alstadter

2007-01-01T23:59:59.000Z

9

Cavitation guide for control valves  

SciTech Connect

This guide teaches the basic fundamentals of cavitation to provide the reader with an understanding of what causes cavitation, when it occurs, and the potential problems cavitation can cause to a valve and piping system. The document provides guidelines for understanding how to reduce the cavitation and/or select control valves for a cavitating system. The guide provides a method for predicting the cavitation intensity of control valves, and how the effect of cavitation on a system will vary with valve type, valve function, valve size, operating pressure, duration of operation and details of the piping installation. The guide defines six cavitation limits identifying cavitation intensities ranging from inception to the maximum intensity possible. The intensity of the cavitation at each limit Is described, including a brief discussion of how each level of cavitation influences the valve and system. Examples are included to demonstrate how to apply the method, including making both size and pressure scale effects corrections. Methods of controlling cavitation are discussed providing information on various techniques which can be used to design a new system or modify an existing one so it can operate at a desired level of cavitation.

Tullis, J.P. [Tullis Engineering Consultants, Logan, UT (United States)

1993-04-01T23:59:59.000Z

10

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

11

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

12

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

SciTech Connect

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

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

2014-01-01T23:59:59.000Z

13

Luminescence from hydrodynamic cavitation  

Science Journals Connector (OSTI)

...higher for monatomic gases than for more complicated...and polyatomic) gases, then the constituent...around 9000K for nitrogen and oxygen, and...ordinary diatomic gases. Only when the gas...hydrodynamic cavitation of water, containing dissolved...pressure. However, the solubility of xenon in water...

2011-01-01T23:59:59.000Z

14

Analysis of bubble cavitation in ultrasound therapy by wavelet technique  

Science Journals Connector (OSTI)

Bubble cavitation is one of the major mechanisms for ultrasound treatment. To understand its characteristics, cavitation signals were picked up using passive cavitation detection and then analysed by wavelet transform. Although the Fast Fourier Transform (FFT) has been used widely in signal analysis, the absence of temporal information is one of its limitations. The inertial cavitation strength detected by wavelet method was ?60 folds higher than that using FFT. Furthermore, the relationship of waveform profile and acoustic pressure with the corresponding bubble cavitation were investigated. All together, wavelet approach could be new tool for studying bubble cavitation.

Yufeng Zhou

2008-01-01T23:59:59.000Z

15

Cavitation-controlled ultrasonic agitator  

SciTech Connect

High-intensity ultrasound generally produces nonlinear acoustic cavitation and streaming in liquids. The ultrasonic energy required to cause cavitation and streaming in a liquid depends on the physical properties of the liquid, e.g., surface tension, viscosity, and entrained gases. Both cavitation and streaming generate acoustic noise whose signatures may be used to distinguish the stage of agitation and thus allow the process to be controlled. An ultrasonic agitator has been designed for application in a confined area with a high-temperature, high-pressure, and corrosive environment. Control of this agitator is based on the detection of noise levels and subharmonics produced during cavitation and streaming. Noise signatures of agitation in different liquids and in liquids with particles have been determined, and discussed. 6 refs., 6 figs.

Sheen, S.H.; Lawrence, W.P.; Raptis, A.C.

1989-10-01T23:59:59.000Z

16

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

E-Print Network (OSTI)

­structure interaction (FSI); Vaporous cavitation; Column separation 1. Introduction Pressure variations in a water-hammer

Tijsseling, A.S.

17

Cavitation problem in heavy duty diesel engines: a literature review  

Science Journals Connector (OSTI)

This paper reviews the existing knowledge on cavitation in general and its effect on diesel engine cylinder liners. A brief definition of cavitation and various cavitation numbers are presented. Various effects involved in the formation, growth and collapse of bubbles are also characterized. The effects of pressure, temperature, and dissolved gas on bubble behaviour are mentioned. An attempt is made to study the various types of damage caused by cavitation on fluid flow machinery. The discussion highlights the amount of damage caused to diesel engine cylinder liners, and lists remedies suggested by numerous experts in the field.

Sunil Katragadda; Reda Bata

1994-01-01T23:59:59.000Z

18

OPTIC CAVITATION W. Lauterborn  

E-Print Network (OSTI)

, especially ship pro- pellers, turbines, pumps and hydrofoils. This type of cavitation is called hydraulic up to a million frames per second. In a series of experiments bubble oscillations in the bulk

Paris-Sud XI, Université de

19

ESTIMATION OF EXHAUST MANIFOLD PRESSURE IN TURBOCHARGED GASOLINE ENGINES WITH VARIABLE VALVE TIMING  

E-Print Network (OSTI)

ESTIMATION OF EXHAUST MANIFOLD PRESSURE IN TURBOCHARGED GASOLINE ENGINES WITH VARIABLE VALVE TIMING in turbocharged gasoline engines with variable valve timing requires knowledge of exhaust mani- fold pressure, Pe control systems for gasoline engines rely heavily on feedforward air-fuel ratio (A/F) control to meet

Grizzle, Jessy W.

20

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

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

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

E-Print Network (OSTI)

Zhang Senior Engineer Postgraduate Wuhan Architectural Design Institute, Wuhan, China, 430014 Chenyh918@263.net Abstract: This paper analyzes energy-saving design for pressure-difference control in a variable flow air...

Chen, Y.; Zhang, Z.

2006-01-01T23:59:59.000Z

22

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… (more)

Kimla, John

2010-01-01T23:59:59.000Z

23

Reconstructing sea-level pressure variability via a feature tracking approach  

Science Journals Connector (OSTI)

This paper is aimed to quantify the contribution of synoptic transients to the full spectrum of space–time variability of sea-level pressure (SLP) in middle latitudes. In previous work by the authors it was shown that tracking cyclones and ...

Sergey Kravtsov; I. Rudeva; Sergey K. Gulev

24

The effects of nonlinear wave propagation on the stability of inertial cavitation  

E-Print Network (OSTI)

In the context of forecasting temperature and pressure fields in high-intensity focussed ultrasound, the accuracy of predictive models is critical for the safety and efficacy of treatment. In such fields inertial cavitation is often observed. Classically, estimations of cavitation thresholds have been based on the assumption that the incident wave at the surface of a bubble was the same as in the far-field, neglecting the effect of nonlinear wave propagation. By modelling the incident wave as a solution to Burgers' equation using weak shock theory, the effects of nonlinear wave propagation on inertial cavitation are investigated using both numerical and analytical techniques. From radius-time curves for a single bubble, it is observed that there is a reduction in the maximum size of a bubble undergoing inertial cavitation and that the inertial collapse occurs earlier in contrast with the classical case. Corresponding stability thresholds for a bubble whose initial radius is slightly below the critical Blake r...

Sinden, David; Saffari, Nader

2009-01-01T23:59:59.000Z

25

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...

Kimla, John

2010-07-14T23:59:59.000Z

26

Onset of cavitation in the quark-gluon plasma  

E-Print Network (OSTI)

We study the onset of bubble formation (cavitation) in the quark-gluon plasma as a result of the reduction of the effective pressure from bulk-viscous corrections. By calculating velocity gradients in typical models for quark-gluon plasma evolution in heavy-ion collisions, we obtain results for the critical bulk viscosity above which cavitation occurs. Since present experimental data for heavy-ion collisions seems inconsistent with the presence of bubbles above the phase transition temperature of QCD, our results may be interpreted as an upper limit of the bulk viscosity in nature. Our results indicate that bubble formation must occur at temperatures below 140 MeV, consistent with the expectation of hadronisation in low temperature QCD.

Habich, Mathis

2014-01-01T23:59:59.000Z

27

Method of forming cavitated objects of controlled dimension  

DOE Patents (OSTI)

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

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

1982-01-01T23:59:59.000Z

28

Method of forming cavitated objects of controlled dimension  

DOE Patents (OSTI)

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

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

1981-02-11T23:59:59.000Z

29

Dynamics of laser?induced cavitation bubbles  

Science Journals Connector (OSTI)

Bubbles in liquids can be formed in a variety of ways. A convenient method to produce a single bubble in a liquid is to focus a short pulse of laser light into the liquid. A bright light?emitting plasma of obviously high pressure expands forming a gas?vapor bubble. After some time bubble expansion stops at some maximum radius. From thereon the bubble starts to shrink driven by the ambient pressure and leading to a violent collapse possibly followed by rebounds. A mathematical model that describes the evolution of such a laser?induced cavitation bubble is presented. The model takes into account heat conduction of the liquid and gas phases evaporation and condensation processes of the liquid phase gas diffusion from the liquid into the bubble and compressibility of the liquid. A reasonable comparison of theoretical results with experimental data is obtained. [Work partially supported by Internationales Büro des BMBF (Contract RUS?133?1997) and European Commission (INCO?Copernicus Contract ERBIC15CT980141).

Iskander Akhatov; Nailya Vakhitova; Kamil Zakirov; Robert Mettin; Olgert Lindau; Werner Lauterborn

1999-01-01T23:59:59.000Z

30

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

DOE Patents (OSTI)

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

31

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

E-Print Network (OSTI)

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

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

2014-02-27T23:59:59.000Z

32

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

33

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

34

Evaporation-induced cavitation in nanofluidic channels  

E-Print Network (OSTI)

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

Karnik, Rohit N.

35

A study on static pressure reset and instability in variable air volume HVAC systems.  

E-Print Network (OSTI)

??This project began with testing five different versions of supply duct static pressure reset strategies that fall into two general categories: Proportional plus Integral control… (more)

Housholder, Brian Wayne

2011-01-01T23:59:59.000Z

36

Techno-economic feasibility study of providing variable frequency drive for high pressure pump, SWRO plant at NDDP, Kalpakkam  

Science Journals Connector (OSTI)

The cost of product water is a key factor in determination of acceptability of any desalination system and plant. In case of Sea Water Reverse Osmosis plants, most of the energy consumed is in the form of electricity. The High Pressure Pump (HPP) is the single major energy consuming equipment with a share of above 75%. Hence reduction in energy consumed by HPP will have a substantial effect on the overall energy consumption. The high starting torque requirement of high pressure pump results in increased acceleration time of the motor which subsequently increases the strain on the upstream electrical system from motor feeder to transformer. Provision of a Variable Frequency Drive can be a solution for both the above problems. This paper studies the techno-economic feasibility of providing variable frequency drive for HPP motor at NDDP, Kalpakkam.

R. Nagaraj; V. Murugan; Ashok Y. Dangore; K.L. Thalor; S. Prabakar; V.K. Srivastava; P.K. Tewari

2010-01-01T23:59:59.000Z

37

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

E-Print Network (OSTI)

turbulent pressure) affects the structure and stability of luminous post­red-supergiant stars is critically zone lies too deep below the surface to influence the formal dynamical stability or instability more than a huge bubble of blackbody radiation. Since radiation pressure tends to decrease stellar

38

Investigation of aluminum surface cleaning using cavitating fluid flow  

SciTech Connect

This paper investigates efficiency of specially designed atomizer used to spray water and cavitate microbubbles in water flow. Surface cleaning system was used to clean machined (grinded) aluminum surface from abrasive particles. It is established that cleaning efficiency depends on diameter of the diffuser, water pressure and distance between nozzle and metal surface. It is obtained that the best cleaning efficiency (100%) is achieved at pressure 36 bar, when diameter of diffuser is 0.4 mm and distance between nozzle and surface is 1 mm. It is also established that satisfactory cleaning efficiency (80%) is achieved not only when atomizer is placed closer to metal surface, but also at larger (120 mm) distances.

Ralys, Aurimas; Striška, Vytautas; Mokšin, Vadim [Vilnius Gediminas Technical University, Faculty of Mechanics, Department of Machine Engineering, J. Basanavi?iaus str.28, 03224, Vilnius (Lithuania)

2013-12-16T23:59:59.000Z

39

Bubble Number in a Caviting Flow Henri Gouin  

E-Print Network (OSTI)

Bubble Number in a Caviting Flow Henri Gouin C.N.R.S. U.M.R. 6181 & Universit´e d of bubbles (a number of bubbles per unit of volume in the flow). The maximum intensity of cavitation; Bubble formation; Bubble dynamics; Cavitation. PACS: 47.55.Ca; 47.55.db; 47.55.dd; 47.55.dp 1

Paris-Sud XI, Université de

40

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

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

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

42

Spheroidal particles produced by cavitation erosion  

Science Journals Connector (OSTI)

... standard vibratory cavitation erosion apparatus and ASTM standard test procedures. Tests were conducted on annealed SAE 52100 steel (supplied by the Timken Company) in ... 52100 steel (supplied by the Timken Company) in SAE lOw non-detergent (Quaker State) lubricating oil and on aluminium 1100-F in distilled ...

STANELY W. DOROFF; RICHARD S. MILLER; ALAGU P. THIRUVENGADAM; VERNON C. WESTCOTT

1974-02-08T23:59:59.000Z

43

E-Print Network 3.0 - acoustic cavitation bubble Sample Search...  

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

Collection: Physics 62 Acoustic saturation in bubbly cavitating flow adjacent to an oscillating wall T. Colonius,a) Summary: Acoustic saturation in bubbly cavitating flow...

44

SIMULATION AND MOCKUP OF SNS JET-FLOW TARGET WITH WALL JET FOR CAVITATION DAMAGE MITIGATION  

SciTech Connect

Pressure waves created in liquid mercury pulsed spallation targets at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory induce cavitation damage on the stainless steel target container. The cavitation damage is thought to limit the lifetime of the target for power levels at and above 1 MW. Severe through-wall cavitation damage on an internal wall near the beam entrance window has been observed in spent-targets. Surprisingly though, there is very little damage on the walls that bound an annular mercury channel that wraps around the front and outside of the target. The mercury flow through this channel is characterized by smooth, attached streamlines. One theory to explain this lack of damage is that the uni-directional flow biases the direction of the collapsing cavitation bubble, reducing the impact pressure and subsequent damage. The theory has been reinforced by in-beam separate effects data. For this reason, a second-generation SNS mercury target has been designed with an internal wall jet configuration intended to protect the concave wall where damage has been observed. The wall jet mimics the annular flow channel streamlines, but since the jet is bounded on only one side, the momentum is gradually diffused by the bulk flow interactions as it progresses around the cicular path of the target nose. Numerical simulations of the flow through this jet-flow target have been completed, and a water loop has been assembled with a transparent test target in order to visualize and measure the flow field. This paper presents the wall jet simulation results, as well as early experimental data from the test loop.

Wendel, Mark W [ORNL; Geoghegan, Patrick J [ORNL; Felde, David K [ORNL

2014-01-01T23:59:59.000Z

45

Vol. 22, No. 3, Aug. 1, 2002 Scientists measure energy dissipation in a single cavitating bubble  

E-Print Network (OSTI)

. Cavitation also is responsible for submarine propeller noise, for erosion of turbines, and for the noise

Suslick, Kenneth S.

46

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

E-Print Network (OSTI)

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

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

2007-01-01T23:59:59.000Z

47

Notes 06. Liquid cavitation in fluid film bearings  

E-Print Network (OSTI)

[s] U ?R. Journal surface speed [m/s] V dh/dt. Squeeze film velocity [m/s] X= ?R, y, z Coordinate system on plane of bearing ? ()/ cav ?? . Density ratio ? P ? ? ? ? . Liquid bulk-modulus [N/m 2 ] ? Liquid density [kg/m 3 ] cav... ? Density at Pcav [kg/m 3 ] ? Fluid absolute viscosity [N.s/m 2 ] ? Journal angular speed (rad/s) Subscripts * Inception of the cavitation zone a Ambient value cav Cavitation NOTES 6. CAVITATION IN LIQUID FILM BEARINGS. Dr. Luis San Andr?s ? 2009...

San Andres, Luis

2009-01-01T23:59:59.000Z

48

On acoustic cavitation of slightly subcritical bubbles Anthony Harkin  

E-Print Network (OSTI)

On acoustic cavitation of slightly subcritical bubbles Anthony Harkin Department of Mathematics, such as submicron air bubbles in water, where the natural oscilla- tion frequencies are high. In contrast, when

Kaper, Tasso J.

49

Crystalline Silicon under Acoustic Cavitation: From Mechanoluminescence to Amorphization  

Science Journals Connector (OSTI)

The physicochemical behavior of crystalline silicon under acoustic cavitation is investigated in water sparged with argon at low temperature (10 and 20 °C). Surprisingly, spectroscopic investigations reveal that argon (bubbling continuously through the ...

Matthieu Virot; Rachel Pflieger; Ekaterina V. Skorb; Johann Ravaux; Thomas Zemb; Helmuth Möhwald

2012-06-21T23:59:59.000Z

50

Acoustic cavitation: the fluid dynamics of non–spherical bubbles  

Science Journals Connector (OSTI)

...penetrating the bubble interior. 4. Bubble behaviour near an oscillating...clean jet penetrating a cavitation bubble in the direction of the oscillating...ent. First, the remarkable stability of the bubble motion--the presumably toroidal...

1999-01-01T23:59:59.000Z

51

On the importance of the effect of turbulence in cavitation inception tests of marine propellers  

Science Journals Connector (OSTI)

...in cavitation inception tests of marine propellers E. Korkut M. Atlar...Proc. Int. Conf. on Problems of Marine Propulsion, HYDRONAV'95, Gda nsk, Poland...cavitation inception and noise in marine propellers. PhD thesis, University...

2002-01-01T23:59:59.000Z

52

Temporal Trends in the Histology of the Rabbit Kidney after Cavitational Tissue Ablation  

Science Journals Connector (OSTI)

Tissue can be mechanically ablated through inertial cavitation generated by high intensity pulsed ultrasound. The ablation appears acutely as a fine slurry with absent cellular structure. Long?term effects and the evolution of histologic changes in disrupted tissue remain poorly understood. This study aimed to characterize the 0–60 day histology of cavitational ablation in a rabbit model. 29 New Zealand White rabbits were anesthetized and exposed to high intensity pulses of ultrasound (60000 pulses 20 usec duration 750 kHz 1 kHz PRF 18 MPa peak rarefactional pressure lower pole left kidney). Kidneys were harvested immediately from five rabbits. The others were recovered and the kidneys were harvested 1 2 7 20 or 60 days after treatment. Grossly kidneys from 0–2 days displayed subcapsular bruising near the exposure site and some hemorrhage in the adjacent perirenal fat; microscopically a disrupted acellular zone measuring 3–5 mm by 5–10 mm accompanied by local infiltration of neutrophils (acute inflammation) was seen. Kidneys harvested after 7 days displayed tubular dilatation adjacent to the targeted area and collagen deposition consistent with scar formation. Decreased collagen deposition decreased size of the disrupted zone and regeneration of the tubular basal cell layer of dilated tubules was evident by day 20. Kidneys harvested at 20 and 60 days had contour defects near the exposure site with an apparent volume loss. Cavitation causes orderly and predictable histologic changes. Local renal damage induced during histotripsy may be partially reversible. Further research is needed to identify the clinical correlates of the observed histologic findings.

Timothy L. Hall; Kathleen Kieran; J. Brian Fowlkes; Charles A. Cain; William W. Roberts

2007-01-01T23:59:59.000Z

53

Active cavitation detection of microbubble echocontrast agents in blood  

Science Journals Connector (OSTI)

Apfel’s active cavitation detector [Roy et al. J. Acoust. Soc. Am. 87 2451–2458 (1990)] has been improved to allow quantification of microbubble activity in reconstituted human blood. One?microsecond?long 20?MHz tone bursts are scattered from microbubbles undergoing transient cavitation at the focus of a pulsed 1?MHz transducer. The host medium consists either of human red blood cells suspended in autologous plasma or platelet?rich plasma with various concentrations of microbubble?based echocontrast agent present. The microbubble activity inferred from the backscattered tone bursts is compared to measured bioeffects (hemolysis platelet aggregation) in order to determine the physical basis for cavitational damage of blood components. Current results as a function of system parameters will be presented. [Work supported by NSF MSS?9253777.

Vilma E. Huertas; Inder Raj S. Makin; E. Carr Everbach

1994-01-01T23:59:59.000Z

54

Inertial cavitation and single–bubble sonoluminescence  

Science Journals Connector (OSTI)

...drive-pressure amplitude increases (from the bottom to...SBSL in CokeTM glasses, wine glasses, and other...The importance of a quality three- dimensional standing...bubble is offset by the increase in the drive-pressure...experimental conditions; the quality of the resonance may...

1999-01-01T23:59:59.000Z

55

Inertial cavitation and single–bubble sonoluminescence  

Science Journals Connector (OSTI)

...there exist regions for bubble stability at higher pressure amplitudes...resonance may affect the bubble's position and stability signifi- cantly. (Note...well as the jitter in the bubble's stability) is measured in picoseconds...

1999-01-01T23:59:59.000Z

56

Cavitation erosion in blocked flow with a ducted ice-class propeller  

SciTech Connect

Ships that operate in ice often encounter momentary increased propeller cavitation because ice pieces block the flow into the propeller. For ducted propellers, this additional cavitation is more significant than it is for open propellers; ice pieces may become lodged against and within the duct and subject the propeller to longer periods of increased cavitation due to the blocked flow. Associated with this blocked flow is the possibility of cavitation erosion on the propeller. An erosion study, using paint films, was conducted in a cavitation tunnel with a model propeller of the type fitted to the Canadian Marine Drilling Ltd. vessel MV Robert LeMeur. A simulated ice blockage was installed ahead of the propeller model and within the duct. Tests were carried out over a range of advance coefficients for various test conditions. The resulting types of cavitation were documented, the erosion patterns were photographed and comparisons between each test were made.

Doucet, J.M.; Bose, N.; Walker, D. [Memorial Univ. of Newfoundland, St. John`s, Newfoundland (Canada). Ocean Engineering Research Centre; Jones, S.J. [National Research Council of Canada, St. John`s, Newfoundland (Canada). Inst. for Marine Dynamics

1996-12-31T23:59:59.000Z

57

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

E-Print Network (OSTI)

On acoustic cavitation of slightly subcritical bubbles Anthony ¡ Harkin Department in liquids when surface tension is the dominant effect, such as submicron air bubbles in water, where

Harkin, Anthony

58

A method for desalination and water remediation by hydrodynamic cavitation  

Science Journals Connector (OSTI)

Water is becoming an increasingly valuable commodity with population growth demanding more and more amounts of this limited resource. Increased efforts are directed toward recycling and remediation as well as desalination of the large quantities of seawater available. Dr. Bertwin Langenecker was a pioneer in utilizing hydrodynamic cavitation in a variety of applications that would remove dissolved solids from water and other liquids. His combination of intense cavitation using a rotor-stator combination as well as simultaneously adding an adsorbent demonstrated impressive results in desalination and waste water remediation. In this presentation a description will be given of Dr. Langenecker’s technology as well as a sampling of some of his most impressive results. Speculations as to why this approach works as well as it does will be presented.

2013-01-01T23:59:59.000Z

59

A method for desalination and water remediation by hydrodynamic cavitation  

Science Journals Connector (OSTI)

Water is becoming an increasingly valuable commodity with population growth demanding more and more amounts of this limited resource. Increased efforts are directed toward recycling and remediation as well as desalination of the large quantities of seawater available. Dr. Bertwin Langenecker was a pioneer in utilizing hydrodynamic cavitation in a variety of applications that would remove dissolved solids from water and other liquids. His combination of intense cavitation using a rotor-stator combination as well as simultaneously adding an adsorbent demonstrated impressive results in desalination and waste water remediation. In this presentation a description will be given of Dr. Langenecker's technology as well as a sampling of some of his most impressive results. Speculations as to why this approach works as well as it does will be presented.

Lawrence A. Crum; Michael Skinner; Scott Zeilinger

2013-01-01T23:59:59.000Z

60

Pseudoplastic deformation pits on polished ceramics due to cavitation erosion  

Science Journals Connector (OSTI)

In a previous study, pseudoplastic deformation pits created by cavitation exposure were reported in silicon nitride and zirconia. In this research, further comparison of the size and number of pits between several silicon nitride and zirconia materials is carried out. The pits are larger and much more numerous in silicon nitride than in zirconia although silicon nitride is harder than zirconia. An explanation of this phenomenon is given. Also, in the previous study it was reported that apparently a partially stabilized zirconia with yttria oxide developed a delay in the phase transformation from tetragonal to monoclinic after being exposed to cavitation. In this research, further experiments related with this phase transformation delay are carried out. Also, the phase transformation is verified with X-ray diffraction analysis. It is concluded that the “activation” of the partial stabilized zirconia happens regardless of the oxide used to stabilize it.

G. García-Atance Fatjó; M. Hadfield; K. Tabeshfar

2011-01-01T23:59:59.000Z

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.


61

Equation of state of water under negative pressure Kristina Davitt,a  

E-Print Network (OSTI)

Equation of state of water under negative pressure Kristina Davitt,a Etienne Rolley, Frédéric equation of state of metastable liquid water down to the acoustic cavitation threshold. Empirical equations of state of water are based on experimental data at positive pressure; the validity of their extrapolation

Caupin, Frédéric

62

A CAVITATION TRACKING METHOD FOR ELASTIC-PLASTIC FLOW IN SOLIDS  

E-Print Network (OSTI)

A CAVITATION TRACKING METHOD FOR ELASTIC-PLASTIC FLOW IN SOLIDS Keh-Ming Shyue Department tracking approach for the numerical simulation of one-dimensional elastic- plastic flow in solids, and the von Mises condition for the elastic-plastic phase change. To characterize the cavitation

Shyue, Keh-Ming

63

Bubble path in the wake of a cavitating propeller  

Science Journals Connector (OSTI)

Propellers that operate underwater at high rpm's cavitate at the tip. The tip cavitation creates air bubbles that are then swept downstream by the motion of the surrounding fluid. In this paper a theory is presented to predict the local velocity and the path of the bubble. The bubble motion is assumed to be governed by a group of terms due to the acceleration of the displaced fluid the convective term and the drag due to the cross?sectional area of the bubble. At very low and very high Reynolds numbers the equations have been solved in closed form. Results are presented for the bubble velocity and path for the following flow fields: (a) uniform axial flow field and (b) uniform flow field with an axially decaying swirling component. In all cases presented the bubble axial velocity component asymptotes to the free stream velocity; the manner in which it asymptotes is exponential at very low Reynolds numbers and algebraic at high Reynolds numbers. Bubble helical paths and velocity patterns are shown for different bubble sizes.

Mauro Picrucci

1988-01-01T23:59:59.000Z

64

On the dynamics and acoustics of cloud cavitation on an oscillating hydrofoil  

SciTech Connect

Observations have been made of the growth and collapse of surface and cloud cavitation on a finite aspect ratio hydrofoil oscillating in pitch. The cavitation was recorded using both still and high-speed motion picture photography, and the variations with cavitation number and reduced frequency of oscillation were investigated. The noise generated by the cavity collapse was also measured and analyzed. The acoustic signals associated with individual cavity collapse events have been synchronized with the motion pictures, providing insights into the correspondence between the flow structures involved in the cavity collapse process and the sound generated by them.

McKenney, E.A.; Brennen, C.E. [California Inst. of Tech., Pasadena, CA (United States). Dept. of Mechanical Engineering

1994-12-31T23:59:59.000Z

65

Cavitation controlled acoustic probe for fabric spot cleaning and moisture monitoring  

DOE Patents (OSTI)

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

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

1997-01-01T23:59:59.000Z

66

Wear resistance of titanium-alloyed high-aluminum bronzes under cavitation  

Science Journals Connector (OSTI)

Aluminum-nickel bronzes are known to have a high cavitation-erosion resistance; this is especially true of bronzes containing 11–14% Al, which can be used to restore worn parts of hydraulic engines, marine engine...

Yu. N. Tsvetkov; L. I. Pogodaev

1994-02-01T23:59:59.000Z

67

Parallel computing of the underwater explosion cavitation effects on full-scale ship structures  

Science Journals Connector (OSTI)

As well as shock wave and bubble pulse loading, cavitation also has very significant influences on the dynamic response of surface ships and other near-surface marine structures to ... single computation and para...

Zhi Zong; Yanjie Zhao; Fan Ye; Haitao Li…

2012-12-01T23:59:59.000Z

68

Numerical and Experimental Investigation into Propulsion and Cavitation Performance of Marine Propeller  

Science Journals Connector (OSTI)

This paper discusses the application of the CFD to transitional and cavitating flow around marine propellers. Especially the emphasis is put on the adaption of the 3 equations turbulence model for the non-cavi...

Nobuhiro Hasuike; Shosaburo Yamasaki…

2013-01-01T23:59:59.000Z

69

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

SciTech Connect

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

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

1985-04-15T23:59:59.000Z

70

Evidence for nuclear emissions during neutron seeded acoustic bubble cavitation  

Science Journals Connector (OSTI)

In cavitation experiments with deuterated acetone statistically significant tritium decay activity above background levels was detected. In addition evidence for statistically significant neutron emissions near 2.5 MeV was also observed as would be expected for deuterium–deuterium fusion. Control experiments with normal acetone did not result in tritium activity or neutron emissions. Hydrodynamic shock code simulations supported the observed data and indicated compressed hot (106–107 K) bubble implosion conditions as required for thermonuclear fusion reactions. Separate experiments with additional fluids are under way and results appear to support those observed with acetone. Scalability potential to higher yields as well as evidence for neutron?tritium branching ratios are presented.

2002-01-01T23:59:59.000Z

71

Ethanol injection induced cavitation and heating in tissue exposed to high intensity focused ultrasound  

Science Journals Connector (OSTI)

High Intensity Focused Ultrasound (HIFU) can ablatetumors located deep in the body through highly localized energy deposition and tissue heating at the target location. The volume of a HIFU-induced thermal lesion can be increased in the presence of cavitation. This study explores the effect of ethanol injection on cavitation and heating in tissue-mimicking phantoms and bovine liver tissues exposed to HIFU. The HIFU transducer (0.825 MHz) operated at seven acoustic power levels ranging from 1.3 W to 26.8 W. The cavitation events were quantified by B-mode ultrasound imaging needle hydrophone measurements and passive cavitation detection (PCD). Temperature in or near the focal zone was measured by thermocouples embedded in the samples. The onset of inertial cavitation in ethanol-treated phantoms and bovine liver tissues occurred at a lower power level than in the untreated samples (control). The cavitation occurrence in turn resulted in a sudden rise of temperature in ethanol-treated samples at a lower acoustic power than that in control. The results of this work indicate that the use of percutaneous ethanol injection prior to HIFU exposure may improve the HIFU therapeutic efficiency.

Chong Chen; Yunbo Liu; Subha Maruvada; Matthew Myers; Damir Khismatullin

2012-01-01T23:59:59.000Z

72

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

E-Print Network (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 ...

Baker-Yeboah, Sheekela

73

Extracting a Whisper from the DIN: A Bayesian-Inductive Approach to Learning an Anticipatory Model of Cavitation  

SciTech Connect

For several reasons, Bayesian parameter estimation is superior to other methods for inductively learning a model for an anticipatory system. Since it exploits prior knowledge, the analysis begins from a more advantageous starting point than other methods. Also, since "nuisance parameters" can be removed from the Bayesian analysis, the description of the model need not be as complete as is necessary for such methods as matched filtering. In the limit of perfectly random noise and a perfect description of the model, the signal-to-noise ratio improves as the square root of the number of samples in the data. Even with the imperfections of real-world data, Bayesian methods approach this ideal limit of performance more closely than other methods. These capabilities provide a strategy for addressing a major unsolved problem in pump operation: the identification of precursors of cavitation. Cavitation causes immediate degradation of pump performance and ultimate destruction of the pump. However, the most efficient point to operate a pump is just below the threshold of cavitation. It might be hoped that a straightforward method to minimize pump cavitation damage would be to simply adjust the operating point until the inception of cavitation is detected and then to slightly readjust the operating point to let the cavitation vanish. However, due to the continuously evolving state of the fluid moving through the pump, the threshold of cavitation tends to wander. What is needed is to anticipate cavitation, and this requires the detection and identification of precursor features that occur just before cavitation starts.

Kercel, S.W.

1999-11-07T23:59:59.000Z

74

EVALUATION OF CAVITATION-CORROSION RESISTANCE AND RECIPROCATING WEAR RESISTANCE OF SURFACE COATED AND CRYOGENICALLY TREATED SILICON BRASS.  

E-Print Network (OSTI)

??Cavitation and corrosion resistance are important characteristics to consider in marine environments with flowing liquid. Impellers and propellers are used in many applications and are… (more)

Simmons, Nathan

2008-01-01T23:59:59.000Z

75

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

SciTech Connect

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

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

2014-01-01T23:59:59.000Z

76

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

E-Print Network (OSTI)

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

Sevostianov, Igor

77

Stability of bubbly liquids and its connection to the process of cavitation inception D. Fuster, K. Pham, and S. Zaleski  

E-Print Network (OSTI)

Stability of bubbly liquids and its connection to the process of cavitation inception D. Fuster, K.1063/1.1416497 Noise induced stabilization of chaotic oscillations of cavitation bubbles AIP Conf. Proc. 524, 519 (2000, 14 Apr 2014 16:11:36 #12;PHYSICS OF FLUIDS 26, 042002 (2014) Stability of bubbly liquids and its

Fuster, Daniel

78

Vibratory cavitation erosion behavior of AISI 304 stainless steel in water at elevated temperatures  

Science Journals Connector (OSTI)

Abstract The cavitation erosion behavior of AISI 304 stainless steel was investigated using an ultrasonic vibratory apparatus at elevated temperatures and the morphologies of the eroded surface and the cross section were observed by scanning electron microscopy (SEM) and optical microscopy. The results show that the cumulative mass loss increases, shows a peak and then decreases with increase in liquid temperature. The cavitation damage of the eroded surface was relatively uniform at 20–60 °C and at 80 °C it was localized; the depth of local deeper pit at 80 °C was about 1.7 times deeper than at 50 °C. The initial results based on the cumulative mass loss could not predict the degree of cavitation damage, and the depth of local erosion pit may be an effective method for judging erosion damage.

Zhen Li; Jiesheng Han; Jinjun Lu; Jiansong Zhou; Jianmin Chen

2014-01-01T23:59:59.000Z

79

Effect of ethanol injection on cavitation and heating of tissues exposed to high-intensity focused ultrasound  

Science Journals Connector (OSTI)

Cavitation activity and temperature rise have been investigated in a tissue-mimicking material and excised bovine liver treated with ethanol and insonated with a 0.825 MHz focused acoustic transducer. The acoustic power was varied from 1.3 to 26.8 W to find the threshold leading to the onset of inertial cavitation. Cavitation events were quantified by three independent techniques: B-mode ultrasound imaging, needle hydrophone measurements and passive cavitation detection. Temperature in or near the focal zone was measured by thermocouples embedded in the samples. The results of this study indicate that the treatment of tissue phantoms and bovine liver samples with ethanol reduces their threshold power for inertial cavitation. This in turn leads to a sudden rise in temperature in ethanol-treated samples at a lower acoustic power than that in untreated ones. The analysis of passive cavitation detection data shows that once the threshold acoustic power is reached, inertial cavitation becomes a major contributor to acoustic scattering in ethanol-treated phantoms and bovine liver samples as compared to control. This study opens up the possibility of improved tumor ablation therapy via a combination of percutaneous ethanol injection and high-intensity focused ultrasound.

C Chen; Y Liu; S Maruvada; M Myers; D Khismatullin

2012-01-01T23:59:59.000Z

80

Ultrasonic emissions reveal individual cavitation bubbles in water-stressed wood  

Science Journals Connector (OSTI)

...the tree (radial plane), allowing most pits connecting conduits to be observed from...ert193 ) 13 Holbrook, NM , ET Ahrens, MJ Burns, and MA Zwieniecki. 2001 In vivo observation...Plasmodesmatal pores in the torus of bordered pit membranes affect cavitation resistance...

2014-01-01T23:59:59.000Z

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.


81

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

SciTech Connect

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

82

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

E-Print Network (OSTI)

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

M. Pekker; M. N. Shneider

2014-12-19T23:59:59.000Z

83

detonation pressure  

Science Journals Connector (OSTI)

detonation pressure ? Detonationsdruck m [Er ist dem Quadrat der Detonationsgeschwindigkeit und der Sprengstoffdichte proportional

2014-08-01T23:59:59.000Z

84

Surface modification by gas nitriding for improving cavitation erosion resistance of CP-Ti  

Science Journals Connector (OSTI)

Abstract Gas nitriding process has been used to increase the surface hardness of titanium, in this study we used this technique to improve the cavitation erosion resistance (Rce) of commercial purity titanium (CP-Ti). We also studied microstructure, phase constituents, hardness and the effect of processing parameters on Rce of the treated samples. The results indicated that the Rce of the treated samples was related to the processing parameters. The sample treated at 850 °C for 4 h has the highest Rce, which was attributed to the compound layer (CL) with a hard, dense and free-defects microstructure. With increasing the nitriding temperature and duration, the Rce of the treated samples decreased due to the excessive oxide and defects formed in the CL. When the CL was removed, the treated sample exhibited an excellent cavitation erosion behavior. It was supposed to be due to the existence of the residual compressive stresses field in the nitrogen diffusion zone, which played an important role in preventing microcracks initiation and propagation to interior for cavitation damage.

Haibin Li; Zhenduo Cui; Zhaoyang Li; Shengli Zhu; Xianjin Yang

2014-01-01T23:59:59.000Z

85

Pressure &Pressure & TemperatureTemperature  

E-Print Network (OSTI)

to measure atmospheric pressure, and thermometer toprobe to measure atmospheric pressure, and thermometer toprobe to measure atmospheric pressure, and thermometer toprobe to measure atmospheric pressure, and thermometer to measure air temperature.measure air temperature.measure air temperature.measure air temperature

California at Santa Cruz, University of

86

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

E-Print Network (OSTI)

and nuclear power plants technologies. Cavitating fluids are multiphase mixtures that often involve complex dedicated in the past decades to the simulation of cavitating flows and liquid-vapor flows with phase change fronts, when heat and mass transfer processes are included in the physical description through thermal

Pelanti, Marica

87

An Investigation on the Nature of Micro Cavitation Bubbles on the Movement of Undersea Vessels and Waves  

E-Print Network (OSTI)

To further understand their nature, micro cavitation bubbles were systematically diffused around the exterior of a test body (tube) fully submerged in a water tank. The primary purpose was to assess the feasibility of applying micro cavitation as a means of depth control for underwater vehicles, mainly but not limited to submarines. Ideally, the results would indicate the use of micro cavitation as a more efficient alternative to underwater vehicle depth control than the conventional ballast tank method. The current approach utilizes the Archimedes' principle of buoyancy to alter the density of the object affected, making it less than, or greater than the density of the surrounding fluid. However, this process is too slow for underwater vehicles to react to sudden obstacles inherent in their environment. Rather than altering its internal density, this research aimed to investigate the response that would occur if the density of its environment was manipulated instead. In theory, and in a hydrostatic fluid, di...

Anderson, Asalie; Hoffman, Derek; Mancas, Stefan C

2014-01-01T23:59:59.000Z

88

Variable Frequency Pump Drives  

E-Print Network (OSTI)

-frequency electric motor drive. What is happenin9 with variable frequency driven pun,ps is a classical illustration that evolution in technical products takes place not only because of changes in the processes served by these products, or because of innovations...-pole 3550 rpm squirrel caqe induction motor became available in the early 1930s that high pressure pumps operating at that speed could be buil t. And now, in the 1980s, the development of the solid-state, variable frequency electric motor drive...

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

89

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

SciTech Connect

Large-scale molecular dynamics (MD) simulations are performed to investigate homogeneous nucleation and growth of nanovoids during cavitation in liquid Cu. We characterize in detail the atomistic cavitation processes by following the temporal evolution of cavities or voids, analyze the nucleation behavior with the mean first-passage time (MFPT) and survival probability (SP) methods, and discuss the results against classical nucleation theory (CNT), the Tolman equation for surface energy, independent calculation of surface tension via integrating the stress profiles, the Johnson-Mehl-Avrami (JMA) growth law, and the power law for nucleus size distributions. Cavitation in this representative metallic liquid is a high energy barrier Poisson processes, and the steady-state nucleation rates obtained from statistical runs with the MFPT and SP methods are in agreement. The MFPT method also yields the critical nucleus size and the Zeldovich factor. Fitting with the Tolman's equation to the MD simulations yields the surface energy of a planar interface (?0.9 J m{sup ?2}) and the Tolman length (0.4–0.5 Ĺ), and those values are in accord with those from integrating the stress profiles of a planar interface. Independent CNT predictions of the nucleation rate (10{sup 33?34} s{sup ?1} m{sup ?3}) and critical size (3–4 Ĺ in radius) are in agreement with the MFPT and SP results. The JMA law can reasonably describe the nucleation and growth process. The size distribution of subcritical nuclei appears to follow a power law with an exponent decreasing with increasing tension owing to coupled nucleation and growth, and that of the supercritical nuclei becomes flattened during further stress relaxation due to void coalescence.

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

2014-06-07T23:59:59.000Z

90

Osmotic Pressure  

Science Journals Connector (OSTI)

... Whetham in which he attempts to consign actual experimental work on osmotic pressure to the humble rôle of showing how far the assumptions made in so-called thermodynamical proofs can be ... actual osmotic processes, and that the experimental work on osmotic pressure does not play that humble rôle to which Mr. Whetham would consign it. ...

LOUIS KAHLENBERG

1906-07-05T23:59:59.000Z

91

Microstructure and cavitation erosion characteristics of Al–Si alloy coating prepared by electrospark deposition  

Science Journals Connector (OSTI)

With a high-power electrospark deposition (ESD) processing unit, an Al–Si coating was prepared on ZL101 aluminum alloy substrate. The Al–Si coating was composed of many thin deposited layers with the thickness of 30–40 ?m and showed peculiar microstructural characteristics. The eutectic Si phase, which was homogenously distributed in the coating, existed in the form of latticed morphology with characteristics of being composed of many fine (~ 50 nm size) spherical Si particles. Hardness tests showed that the microhardness of the coating was in the range of 100–110 HV with a small fluctuation, which implied that the deposited coating possess a uniform strength through the whole coating. After 4 hours' cavitation erosion tests, the cumulative volume loss of Al–Si coating (9.03 mm3) was only 31.5% of the substrate (28.66 mm3), which indicated that the Al–Si coating possessed better cavitation erosion resistance than ZL101 substrate. The excellent performance of Al–Si coating was mainly attributed to the peculiar microstructure and the formation of fine spherical Si particles.

Wei-fu Wang; Mao-cai Wang; Feng-jiu Sun; Yu-gui Zheng; Jian-min Jiao

2008-01-01T23:59:59.000Z

92

Prediction of far-field acoustic emissions from cavitation clouds during shock wave lithotripsy for development of a clinical device  

Science Journals Connector (OSTI)

...lithotripter focal point. The power spectral density for each panel...generated when the lithotripter is fired, producing pickup on the device...measurement methods for high power/cavitating ultrasound fields...Field, and AJ Walton. 1988 Gas compression and jet formation...

2013-01-01T23:59:59.000Z

93

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

94

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...

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

2007-01-01T23:59:59.000Z

95

Fission gas bubble nucleated cavitational swelling of the alpha-uranium phase of irradiated U-Pu-Zr fuel  

SciTech Connect

Cavitational swelling has been identified as a potential swelling mechanism for the alpha uranium phase of irradiated U-Pu-Zr metal fuels for the Integral Fast Reactor being developed at Argonne National Laboratory. The trends of U-Pu-Zr swelling data prior to fuel cladding contact can be interpreted in terms of unrestrained cavitational driven swelling. It is theorized that the swelling mechanisms at work in the alpha uranium phase can be modeled by single vacancy and single interstitial kinetics with intergranular gas bubbles providing the void nuclei, avoiding the use of complicated defect interaction terms required for the calculation of void nucleation. The focus of the kinetics of fission gas evolution as it relates to cavitational swelling is prior to the formation of a significant amount of interconnected porosity and is on the development of small intergranular gas bubbles which can act as void nuclei. Calculations for the evolution of intergranular fission gas bubbles show that they provide critical cavity sizes (i.e., the size above which the cavity will grow by bias-driven vacancy flux) consistent with the observed incubation dose for the onset of rapid swelling and gas release.

Rest, J.

1992-04-01T23:59:59.000Z

96

Pressure transducer  

DOE Patents (OSTI)

A pressure transducer suitable for use in high temperature environments includes two pairs of induction coils, each pair being bifilarly wound together, and each pair of coils connected as opposite arms of a four arm circuit; an electrically conductive target moveably positioned between the coil pairs and connected to a diaphragm such that deflection of the diaphragm causes axial movement of the target and an unbalance in the bridge output.

Anderson, Thomas T. (Downers Grove, IL); Roop, Conard J. (Lockport, IL); Schmidt, Kenneth J. (Midlothian, IL); Gunchin, Elmer R. (Lockport, IL)

1989-01-01T23:59:59.000Z

97

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

E-Print Network (OSTI)

variations in a water-hammer incident can cause low absolute pressures that enable vaporous and/or gaseous

Eindhoven, Technische Universiteit

98

Three precision differential pressure indicators for operation at high temperatures and pressures  

E-Print Network (OSTI)

, the design did have a 7 Pa sensitivity which is especially imoortant as the sensing transformer was located outside the pressure containment. This feature eliminates the need for electrical feedthroughs which usually limit the operating conditions... was constructed and the sensitivity increased to ? 5 -1 2x10 Pa using the same transformer. Based on the designs tested, a new differential pressure indicator was proposed. Using a diaphragm with a linear variable differential transformer outside the pressure...

Osburn, Douglas Clayton

1981-01-01T23:59:59.000Z

99

Cavitation as a complementary tool for automotive aerodynamics J.F. Beaudoin, O. Cadot, J.L. Aider, K. Gosse, P. Paranthoen, B. Hamelin,  

E-Print Network (OSTI)

Cavitation as a complementary tool for automotive aerodynamics J.F. Beaudoin, O. Cadot, J.L. Aider consists in reducing the aerodynamic drag of the vehicles. As a matter of fact, aerodynamic forces play and Sovran 1993; Hucho 1998). Since the pioneering work of Morel (1978) and Ahmed (1983) about aerodynamics

Wesfreid, José Eduardo

100

E-Print Network 3.0 - arterial pulse pressure Sample Search Results  

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

<< < 1 2 3 4 5 > >> 1 ORAL PRESENTATION ABSTRACT Design of an Arterial Blood Pressure, Heart Rate Variability and Breathing Rate Measuring Summary: artery PPG waveform. Since PTT...

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

PressurePressure Indiana Coal Characteristics  

E-Print Network (OSTI)

TimeTime PressurePressure · Indiana Coal Characteristics · Indiana Coals for Coke · Coal Indiana Total Consumption Electricity 59,664 Coke 4,716 Industrial 3,493 Major Coal- red power plantsTransportation in Indiana · Coal Slurry Ponds Evaluation · Site Selection for Coal Gasification · Coal-To-Liquids Study, CTL

Fernández-Juricic, Esteban

102

Variable trim compressor – a new approach to variable compressor geometry  

Science Journals Connector (OSTI)

ABSTRACT Variable compressor geometry can be employed irrespective of the combustion process selected. It provides the capability of improving response behavior, reducing fuel consumption or cutting exhaust emissions from exhaust-gas turbocharged engines. Previous concepts on variable compressor geometries have been based on using inlet guide vanes to impart a swirl motion to the air that is fed to the compressor with the ultimate aim of enhancing the angle at which the flow of air enters the blade channel. This paper shows an inlet guide configuration that is based on a different operating principle. The inlet guide assembly shown here is designed in a way that minimizes any pressure losses even at high flow rates. Numerical studies were carried out using CFD to test the system's sensitivity. Based on these studies, a rigid conical element was then produced and the potential for increasing efficiency (up to 7% points) and shifting the surge line (up to 33%) verified on a turbocharger test bench. Finally, a design configuration is presented for a variable system.

P. Grigoriadis; S. Müller; A. Benz; M. Sens

2012-01-01T23:59:59.000Z

103

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

104

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

E-Print Network (OSTI)

. Yet, it has been only until recently that this technique has been combined with micro- fluidic chips 5 with the bubble's acoustic emission using a hydro- phone. The bubbles are created with a tightly focused laser the back aperture of the micro- scope objective. The narrow gap is illuminated from the top through

Ohl, Claus-Dieter

105

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

E-Print Network (OSTI)

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

Khandare, Milind Nandkumar

2012-02-14T23:59:59.000Z

106

High temperature pressure gauge  

DOE Patents (OSTI)

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

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

1981-01-01T23:59:59.000Z

107

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

108

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 +

109

High-pressure crystallography  

Science Journals Connector (OSTI)

The history and development of high-pressure crystallography are briefly described and examples of structural transformations in compressed compounds are given. The review is focused on the diamond-anvil cell, celebrating its 50th anniversary this year, the principles of its operation and the impact it has had on high-pressure X-ray diffraction.

Katrusiak, A.

2007-12-21T23:59:59.000Z

110

PRESSURE ACTIVATED SEALANT TECHNOLOGY  

SciTech Connect

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

111

Master external pressure charts  

SciTech Connect

This paper presents a method to develop master external pressure charts from which individual external pressure charts for each material specification may be derived. The master external charts can represent a grouping of materials with similar chemical composition, similar stress-strain curves but produced to different strength levels. External pressure charts are used by various Sections of the ASME Boiler and Pressure Vessel and Piping Codes to design various components such as cylinders, sphered, formed heads, tubes, piping, rings and other components, subjected to external pressure or axial compression loads. These charts are pseudo stress-strain curves for groups of materials with similar stress-strain shapes. The traditional approach was originally developed in the 1940`s and is a graphical approach where slopes to the strain curves are drawn graphically from which pseudo-strain levels are calculated. The new method presented in this paper develops mathematical relationships for the material stress-strain curves and the external pressure charts. The method has the ability to calculate stress-strain curves from existing external pressure charts. The relationships are a function of temperature, the modulus of elasticity, yield strength, and two empirical material constants. In this approach, conservative assumptions used to assign materials to lower bound external pressure charts can be removed. This increases the buckling strength capability of many materials in the Code, providing economic benefits while maintaining the margin of safety specified by the Code criteria. The method can also reduce the number of material charts needed in the Code and provides for the capability to extend the existing pressure charts to higher design temperatures. The new method is shown to contain a number of improvements over the traditional approach and is presently under consideration by appropriate ASME Code committees.

Michalopoulos, E. [Hartford Steam Boiler Inspection and Insurance Co., CT (United States). Codes and Standards Dept.

1996-12-01T23:59:59.000Z

112

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

113

High pressure counterflow CHF.  

E-Print Network (OSTI)

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

Walkush, Joseph Patrick

1975-01-01T23:59:59.000Z

114

Nonlinear optomechanical pressure  

E-Print Network (OSTI)

A transparent material exhibits ultra-fast optical nonlinearity and is subject to optical pressure if irradiated by a laser beam. However, the effect of nonlinearity on optical pressure is often overlooked, even if a nonlinear optical pressure may be potentially employed in many applications, as optical manipulation, biophysics, cavity optomechanics, quantum optics, optical tractors, and is relevant in fundamental problems as the Abraham-Minkoswky dilemma, or the Casimir effect. Here we show that an ultra-fast nonlinear polarization gives indeed a contribution to the optical pressure that also is negative in certain spectral ranges; the theoretical analysis is confirmed by first-principles simulations. An order of magnitude estimate shows that the effect can be observable by measuring the deflection of a membrane made by graphene.

Claudio Conti; Robert Boyd

2014-03-08T23:59:59.000Z

115

Variable Frequency Drives  

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

How BPA Supports VFDs Rebates are available from your utility for Variable Frequency Drives on pumps 20hp or greater and storage fans.. Energy savings from VFDs vary and can...

116

Pressure Relief Devices for High-Pressure Gaseous Storage Systems...  

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

Pressure Relief Devices for High-Pressure Gaseous Storage Systems: Applicability to Hydrogen Technology A. Kostival, C. Rivkin, W. Buttner, and R. Burgess National Renewable Energy...

117

Design and development of a high resolution differential pressure transducer for use at high temperature and high pressure  

E-Print Network (OSTI)

are multiple diaphragms attached at the edges. Flat and corrugated diaphragms are discussed at length by Giovanni (1982). The three most common detection systems are strain gauges, capacitance gauges, and linear variable differential transformers (LVDT... be necessary to connect the resistor and ratio transformer to. the same secondary coil to balance the voltage of the . two secondary coils. Samplers Inlet Inert Fluid Inlet Pressure Housing Electrical Feedthrough LVDT Coils Magnetic Core Pressure...

Childers, Laren Paul

1984-01-01T23:59:59.000Z

118

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

119

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

120

Direct measurement of onset and offset phonation threshold pressure in normal subjects  

Science Journals Connector (OSTI)

Phonation threshold pressures were directly measured in five normal subjects in a variety of voicing conditions. The effects of fundamental frequency intensity closure speed of the vocal folds and laryngeal airway resistance on phonation threshold pressures were determined. Subglottic air pressures were measured using percutaneous puncture of the cricothyroid membrane. Both onset and offset of phonation were studied to see if a hysteresis effect produced lower offset pressures than onset pressures. Univariate analysis showed that phonation threshold pressure was influenced most strongly by fundamental frequency and intensity. Multiple linear regression showed that these two variables as well as laryngeal airway resistance most strongly predicted phonation threshold pressure. Two of the five subjects demonstrated a significant hysteresis effect but one subject actually had higher offset pressures than onset pressures.

Randall L. Plant; Gary L. Freed; Richard E. Plant

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.


121

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, Ralph L.; Dixon, Kenneth L.

2013-09-23T23:59:59.000Z

122

On currents, internal and inertial waves in a stratified ocean due to variable winds. Part 1  

Science Journals Connector (OSTI)

The response of a continuously stratified viscous ocean to a variable wind air pressure field has been studied during recent years by means of analytical methods. This requires the assumption of constant eddy ...

Prof. Dr. W. Krauss

1976-01-01T23:59:59.000Z

123

On currents, internal and inertial waves in a stratified ocean due to variable winds. Part 2  

Science Journals Connector (OSTI)

The response of a continuously stratified viscous ocean to a variable wind and air pressure field has been studied during recent years by means of analytical methods. This requires the assumption of consntant ...

Prof. Dr. W. Krauss

1976-01-01T23:59:59.000Z

124

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

E-Print Network (OSTI)

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

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

2002-01-01T23:59:59.000Z

125

Reference Handbook: Pressure detectors  

SciTech Connect

The purpose of this handbook is to provide Rocky Flats personnel with the information necessary to understand pressure detection. Upon completion of this handbook you should be able to do the following: Define pressure in terms of force and area. Describe the basic operating principles of the U-Tube Manometer. Demonstrate proper techniques for reading Manometers. Describe the basic operating principles of the three types of Bourdon Tubes. Explain the difference between diaphragm. and bellows-type pressure measurement devices. This handbook is designed for use by experienced Rocky Flats operators to reinforce and improve their current knowledge level, and by entry-level operators to ensure that they possess a minimum level of fundamental knowledge. Pressure Detectors is applicable to many job classifications and can be used as a reference for classroom work or for self-study. Although this reference handbook is by no means all-encompassing, you will gain enough information about this subject area to assist you in contributing to the safe operations of Rocky Flats Plant.

Not Available

1990-11-09T23:59:59.000Z

126

The Chemistry of Methane Remediation by a Non?thermal Atmospheric Pressure Plasma  

Science Journals Connector (OSTI)

The destruction of methane by a non?thermal plasma in atmospheric pressure gas streams of nitrogen with variable ... determined by on?line FTIR spectroscopy and the plasma chemistry is interpreted using kinetic m...

Kirsty J. Pringle; J. Christopher Whitehead…

2004-09-01T23:59:59.000Z

127

The effect of particle shape on pressure drop in a turbulent gas-solid suspension  

E-Print Network (OSTI)

was to experimentally compare the pressure drop in suspensions of spherical particles versus fibrous particles in the same apparatus and at the same operating conditions. The previous investigators have varied the particle size, loading ratio (lbs. flowing solids... is for a model which will predict the suspension pressure drop based on such variables as particle size and shape, Reynolds number, loading ratio, electrostatic charge, and other variables. CHAPTER II REVIEW OF LITERATURE A. General Interest in Gas-Solid...

Coughran, Mark Thomas

1984-01-01T23:59:59.000Z

128

Modeling variable density effects in turbulent flames -- Some basic considerations  

SciTech Connect

The paper discusses the basic physical phenomena involved in pressure-density interactions, and presents models of pressure-velocity, pressure-scalar, baroclinic and dilatation effects for variable density low Mach-number turbulence. Their implementation in the {kappa}-{epsilon} framework is then described and their performance evaluated. The models assume that both scalar transport and turbulence generation arising from pressure-density interactions in flames are caused by the motion of large scale turbulent thermals superposed on the normal turbulence mechanism. The velocity of the thermals is related directly to the mean pressure gradient and local density differences in the flames. It is furthermore assumed that the correction for dilatation effects in the {kappa}-{epsilon} system can be determined from the constraint of conservation of the angular momentum of turbulence per unit mass. Simple corrections of the {kappa}-{epsilon} system are proposed for fast chemistry diffusion and premixed flames subject to variable pressure gradients, which offer substantial improvements in the predictions of the flames. some problems remain, particularly in predictions of turbulence in premixed flames, owing to large scale instabilities of the flames observed in the experiments.

Chomiak, J.; Nisbet, J.R. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Thermo and Fluid Dynamics] [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Thermo and Fluid Dynamics

1995-08-01T23:59:59.000Z

129

Envera Variable Compression Ratio Engine  

SciTech Connect

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

130

Variable depth core sampler  

DOE Patents (OSTI)

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

Bourgeois, Peter M. (Hamburg, NY); Reger, Robert J. (Grand Island, NY)

1996-01-01T23:59:59.000Z

131

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

132

Variable depth core sampler  

DOE Patents (OSTI)

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

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

1996-02-20T23:59:59.000Z

133

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

134

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

135

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

136

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).

137

Analysis and simplification of a mathematical model for high-pressure food processes  

Science Journals Connector (OSTI)

Nowadays, consumers look for minimally processed, additive-free food products that maintain their organoleptic properties. This has led to the development of new technologies for food processing. One emerging technology is high hydrostatic pressure, ... Keywords: Boundary layer solution, Food technology, Heat transfer, High pressure, Modelling, Separation of variables solution

N. A. S. Smith, S. L. Mitchell, A. M. Ramos

2014-01-01T23:59:59.000Z

138

Luminescence from hydrodynamic cavitation  

Science Journals Connector (OSTI)

...vibrations, and may affect the efficiency of a hydraulic system, such as a pump or a turbine. The level of understanding...200-650nm response, quantum efficiency 20% at 400nm, rise time...300-820nm, peak quantum efficiency 20% at 420nm). The...

2011-01-01T23:59:59.000Z

139

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

E-Print Network (OSTI)

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

Czaja, Arnaud

140

Differential pressure pin discharge apparatus  

DOE Patents (OSTI)

Disclosed is a discharge assembly for allowing elongate pins to be discharged from an area of relatively low pressure to an area of relatively greater pressure. The discharge assembly includes a duck valve having a lip piece made of flexible material. The flexible lip piece responds to a fluctuating pressure created downstream by an aspirator. The aspirator reduces the downstream pressure sensed by the duck valve when the discharge assembly is in the open position. This allows elongate pins to be moved through the duck valve with no backflow because the aspirator pressure is less than the pressure in the low pressure area from which the pins originate. Closure of the assembly causes the aspirator static pressure to force the flexible duck valve lip piece into a tightly sealed position also preventing backflow. The discharge assembly can be easily controlled using a single control valve which blocks the flow of aspirator gas and closes the pin passageway extending through the assembly.

Oakley, David J. (Richland, WA)

1987-01-01T23:59:59.000Z

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.


141

High-Pressure Hydrogen Tanks  

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

Presentation on High-Pressure Hydrogen Tanks for the DOE Hydrogen Delivery High-Pressure Tanks and Analysis Project Review Meeting held February 8-9, 2005 at Argonne National Laboratory

142

Resumming the pressure  

E-Print Network (OSTI)

The convergence properties of the resummed thermal perturbation series for the thermodynamic pressure are investigated by comparison with the exact results obtained in large-N phi^4 theory and possibilities for improvements are discussed. By going beyond conventional resummed perturbation theory, renormalization has to be carried out nonperturbatively yet consistently. This is exemplified in large-N phi^4_4 and in a special large-N \\phi^3_6 model that mimics QED in the limit of large flavour number.

Anton Rebhan

1998-09-21T23:59:59.000Z

143

PHP: Constructs and Variables Introduction  

E-Print Network (OSTI)

PHP: Constructs and Variables Introduction This document describes: 1. the syntax and types of variables, 2. PHP control structures (i.e., conditionals and loops), 3. mixed-mode processing, 4. how to use one script from within another, 5. how to define and use functions, 6. global variables in PHP, 7

Vander Zanden, Brad

144

Combustor oscillation pressure stabilizer  

SciTech Connect

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

145

Stabilizing System Pressure | Department of Energy  

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

System Pressure This tip sheet summarizes three methods used to stabilize compressed air system pressure: adequate primary and secondary storage, PressureFlow Controllers (P...

146

Theoretical collapse pressures for two pressurized torispherical heads  

SciTech Connect

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

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

1995-12-01T23:59:59.000Z

147

Cradle and pressure grippers  

DOE Patents (OSTI)

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

Muniak, John E. (New York, NY)

2001-01-01T23:59:59.000Z

148

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

149

Steam Oxidation at High Pressure  

SciTech Connect

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

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

2013-07-19T23:59:59.000Z

150

Energy Systems High Pressure Test Laboratory (Fact Sheet)  

SciTech Connect

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

151

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 +

152

Neutron scattering at high pressure  

Science Journals Connector (OSTI)

Neutron scattering spectra at pressures up to 30 kilobar in the temperature range 300–4 K have been obtained with a compact clamped type apparatus. The pressure cell geometry by allowing the detection of neutronsscattered in a plane makes it compatible with operation on crystal spectrometers both for elastic and inelastic scattering. The instrument is light (4.5 kg) and easy to move. An external diameter of 68 mm makes the pressure cell adaptable to standard cryostats or furnaces.

D. Bloch; J. Paureau; J. Voiron; G. Parisot

1976-01-01T23:59:59.000Z

153

Atmospheric Pressure Deposition for Electrochromic Windows |...  

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

Atmospheric Pressure Deposition for Electrochromic Windows Atmospheric Pressure Deposition for Electrochromic Windows Emerging Technologies Project for the 2013 Building...

154

Monitoring variability of multivariate processes  

Science Journals Connector (OSTI)

The paper focuses on determining changes in process variability of multivariate processes. The problem is compounded by the fact that any of the elements in the variance-covariance matrix of variables could change, leading to a change in the process variability. While it may not be feasible to maintain individual control charts for each element of the variance-covariance matrix, some aggregate measure of the variability criteria could be monitored to initially determine if a change has occurred in the process variability. A couple of aggregate measures are proposed and the performance of these suggested measures is explored through a simulation procedure. Compared to the traditional method, which monitors the determinant of the variance-covariance matrix, these alternatives perform well. The performance measure used is the mean time to first detection of a change in the process variability.

Amitava Mitra; Mark Clark

2014-01-01T23:59:59.000Z

155

Pressure testing of torispherical heads  

SciTech Connect

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

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

1995-12-01T23:59:59.000Z

156

Variation of Treeline Mountain Birch Establishment Under Herbivory Pressure  

E-Print Network (OSTI)

model for differential impacts of herbivory pressure on different treeline types, presented in Cairns and Moen (2004). ................. 54 4 Map of herding districts, weather stations, and study site locations .......... 55 5 Vegetation... not been uniform. This variability is attributable to a number of factors, including past human land use, vegetation history, climate history, and herbivory, among others (Körner & Paulsen, 2004). As the scope of investigation is narrowed from global...

Granberg, Tynan

2012-10-19T23:59:59.000Z

157

Pressure Vessel Burst Program: Automated hazard analysis for pressure vessels  

SciTech Connect

The design, development, and use of a Windows based software tool, PVHAZARD, for pressure vessel hazard analysis is presented. The program draws on previous efforts in pressure vessel research and results of a Pressure Vessel Burst Test Study. Prior papers on the Pressure Vessel Burst Test Study have been presented to the ASME, AIAA, JANNAF, NASA Pressure Systems Seminar, and to a DOD Explosives Safety Board subcommittee meeting. Development and validation is described for simplified blast (overpressure/impulse) and fragment (velocity and travel distance) hazard models. The use of PVHAZARD in making structural damage and personnel injury estimates is discussed. Efforts in-progress are reviewed including the addition of two-dimensional and three-dimensional (2D and 3D) hydrodynamic code analyses to supplement the simplified models, and the ability to assess barrier designs for protection from fragmentation.

Langley, D.R. [Aerospace Corp., Kennedy Space Center, FL (United States); Chrostowski, J.D. [ACTA Inc., Torrance, CA (United States); Goldstein, S. [Aerospace Corp., El Segundo, CA (United States); Cain, M. [General Physics Corp., Titusville, FL (United States)

1996-12-31T23:59:59.000Z

158

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

159

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)

160

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.

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

Fundamentals of high pressure adsorption  

SciTech Connect

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

162

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)

163

Selection automatique de variables pertinentes  

E-Print Network (OSTI)

S´election automatique de variables pertinentes Vers la d´ecouverte de nouvelles modalit´es sensori-motrices corr´elations entre ses variables sensori-motrices afin d'apprendre `a r´esoudre sa t^ache d

Boyer, Edmond

164

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.

165

Sub-daily Statistical Downscaling of Meteorological Variables Using Neural Networks  

SciTech Connect

A new open source neural network temporal downscaling model is described and tested using CRU-NCEP reanal ysis and CCSM3 climate model output. We downscaled multiple meteorological variables in tandem from monthly to sub-daily time steps while also retaining consistent correlations between variables. We found that our feed forward, error backpropagation approach produced synthetic 6 hourly meteorology with biases no greater than 0.6% across all variables and variance that was accurate within 1% for all variables except atmospheric pressure, wind speed, and precipitation. Correlations between downscaled output and the expected (original) monthly means exceeded 0.99 for all variables, which indicates that this approach would work well for generating atmospheric forcing data consistent with mass and energy conserved GCM output. Our neural network approach performed well for variables that had correlations to other variables of about 0.3 and better and its skill was increased by downscaling multiple correlated variables together. Poor replication of precipitation intensity however required further post-processing in order to obtain the expected probability distribution. The concurrence of precipitation events with expected changes in sub ordinate variables (e.g., less incident shortwave radiation during precipitation events) were nearly as consistent in the downscaled data as in the training data with probabilities that differed by no more than 6%. Our downscaling approach requires training data at the target time step and relies on a weak assumption that climate variability in the extrapolated data is similar to variability in the training data.

Kumar, Jitendra [ORNL] [ORNL; Brooks, Bjřrn-Gustaf J. [University of Illinois, Urbana-Champaign] [University of Illinois, Urbana-Champaign; Thornton, Peter E [ORNL] [ORNL; Dietze, Michael [University of Illinois, Urbana-Champaign] [University of Illinois, Urbana-Champaign

2012-01-01T23:59:59.000Z

166

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

167

Low pressure carbonylation of heterocycles  

DOE Patents (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

168

High Pressure Hydrogen Tank Manufacturing  

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

Cycles Fuel Lines * 10,000 psi nominal working pressure * O-ring face seal connections * CNC bent to CAD data * 316 Stainless Steel (Other materials available) * Welded end form or...

169

Pressure compensated flow control valve  

DOE Patents (OSTI)

The invention is an air flow control valve which is capable of maintaining a constant flow at the outlet despite changes in the inlet or outlet pressure. The device consists of a shell assembly with an inlet chamber and outlet chamber separated by a separation plate. The chambers are connected by an orifice. Also located within the inlet chamber is a port controller assembly. The port controller assembly consists of a differential pressure plate and port cap affixed thereon. The cap is able to slide in and out of the orifice separating the inlet and outlet chambers. When the pressure differential is sufficient, the differential pressure plate rises or falls to maintain a constant air flow. Movement of the port controller assembly does not require the use of seals, diaphragms, tight tolerances, bushings, bearings, hinges, guides, or lubricants.

Minteer, Daniel J. (West Richland, WA)

1999-01-01T23:59:59.000Z

170

BIOMACROMOLECULES UNDER HIGH HYDROSTATIC PRESSURE  

E-Print Network (OSTI)

of water into the protein rather than the transfer of hydrophobic residues into water. To investigate water. Gil Toombes for teaching me SAXS analysis and help with the pressure pump motor control, Buz Barstow

Gruner, Sol M.

171

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.

172

Measuring the pressure in ultrahigh-pressure mercury arcs  

SciTech Connect

Ultrahigh-pressure (UHP) mercury lamps are important as high-brightness light sources for digital projection. Hg pressures are usually above 20 MPa and difficult to measure. We have built special UHP lamps with a liquid Hg condensate in a temperature-controlled reservoir, allowing us to tune the Hg vapor pressure p between 14 and 30 MPa. As a simple measure for p, we recorded the width DELTAlambda of the 546 nm Hg line while varying p and also the lamp current I and voltage U. The data define a function p(DELTAlambda,I,U) that will deliver p to better than 3% from simple measurements of DELTAlambda, I, and U for most UHP lamps in the important 100-200 W power range. The method is applied to sample lamps, yielding pressures up to 26 MPa and demonstrating how filled Hg amount, burning position, arc gap, and lamp power affect the pressure. The effective temperature of typical UHP lamps is found to be 2400 K. We also derive an improved characteristic U(d,p,I) for the dependence of the arc voltage on arc gap, pressure, and current for electrode-stabilized Hg discharges in the UHP regime. Some aspects of the experiment are of general interest in the field of discharge lamps, such as a model for the heat balance of the Hg condensate under conductive, radiative, and evaporative cooling/heating, a short discussion of high-temperature vapor-pressure data for Hg, and an improved Hg equation of state for UHP conditions.

Hechtfischer, U.; Engelbrecht, B.; Carpaij, M.; Fischer, E.; Koerber, A. [Philips Research Laboratories, Weisshausstrasse 2, 52066 Aachen (Germany)

2009-09-01T23:59:59.000Z

173

Endografts, Pressure, and the Abdominal Aortic Aneurysm  

E-Print Network (OSTI)

surveillance protocols [28]. The relationship between peripheral arterial pressure and aortic pulse pressure was shown to be an underestimation of the pulse pressure within the abdominal aorta by a mean of 10% with a sphygmomanometer which was similar to a...

Meyer, Clark A.

2010-07-14T23:59:59.000Z

174

Flexible Pressure Sensors: Modeling and Experimental Characterization  

E-Print Network (OSTI)

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

Viana, J.C.

175

High pressure synthesis gas conversion. Task 3: High pressure profiles  

SciTech Connect

The purpose of this research project was to build and test a high pressure fermentation system for the production of ethanol from synthesis gas. The fermenters, pumps, controls, and analytical system were procured or fabricated and assembled in our laboratory. This system was then used to determine the effects of high pressure on growth and ethanol production by C. 1jungdahlii. The limits of cell concentration and mass transport relationships were found in CSTR and immobilized cell reactors (ICR). The minimum retention times and reactor volumes were found for ethanol production in these reactors.

Not Available

1993-05-01T23:59:59.000Z

176

Reading with fixed and variable character pitch  

Science Journals Connector (OSTI)

We compared the effects of fixed and variable (proportional) spacing on reading speeds and found variable pitch to yield better performance at medium and large character sizes and...

Arditi, Aries; Knoblauch, Kenneth; Grunwald, Ilana

1990-01-01T23:59:59.000Z

177

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

178

Deep-Sea Research II 50 (2003) 21832204 Temperature and salinity variability in the exit passages  

E-Print Network (OSTI)

-strait gradient in near-surface temperature and salinity through the outflow straits, except in Lombok StraitDeep-Sea Research II 50 (2003) 2183­2204 Temperature and salinity variability in the exit passages pressure gauges at each side of the straits, equipped with temperature and salinity sensors

Sprintall, Janet

179

Integrated Analysis for the Design of Reusable TPS based on Variable Transpiration Cooling for Hypersonic Cruise  

E-Print Network (OSTI)

with the high dynamic pressure flight trajectories, generates surface temperatures for which the strength1 Integrated Analysis for the Design of Reusable TPS based on Variable Transpiration Cooling of hypersonic air-breathing vehicles presents formidable challenges. Reusable thermal protection systems (TPS

Texas at Arlington, University of

180

Multiproxy evidence of Holocene climate variability from estuarine sediments, eastern North America  

E-Print Network (OSTI)

to examine the Holocene evolution of North Atlantic Oscillation (NAO)-type climate variability. Precipitation between precipitation in the two regions at both millennial and centennial timescales. Citation: Cronin, T. During the positive (negative) phase of the NAO, there is an increased (decreased) pressure gradient

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

Reducing uncertainty in geostatistical description with well testing pressure data  

SciTech Connect

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

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

1997-08-01T23:59:59.000Z

182

Operating Reserves and Variable Generation  

SciTech Connect

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

183

Cosmological models with variable constants  

E-Print Network (OSTI)

The behavior of the constants, G,c,h,a,e,m and Lambda, considering them as variable, in the framework of a flat cosmological model with FRW symmetries described by a bulk viscous fluid and considering mechanisms of adiabatic matter creation are investigated. Within two models; one with radiation predominance and another of matter predominance, this behavior are studied.

J. A. Belinchon

1999-07-01T23:59:59.000Z

184

Stirling engine with pressurized crankcase  

SciTech Connect

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

185

Gas Exchange, Partial Pressure Gradients,  

E-Print Network (OSTI)

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

Riba Sagarra, Jaume

186

Recent high pressure photoluminescence studies  

SciTech Connect

In this paper we discuss two studies involving the effect of pressure on luminescence properties of organic molecules in polymeric media. (1) The efficiency of energy transfer from Coumarine 138 to Rhodamine B in polyacrylic acid (PAA) is measured by both steady state and time dependent methods. The Forster efficiency'' obtained by these two methods is consistent and shows the same pressure dependence as efficiencies derived from relative peak intensities. The non-monotonic pressure dependence of the efficiency is accounted for in terms of the properties of the molecules and the media. (2) The effect of pressure on the luminescent efficiency of molecules with two or more possible excited state geometries has been measured. The efficiency is described in terms of the non-radiative dissipation of energy from a planar excited state and the rates of crossing to and from the possible twisted states as well as non-radiative decay from these states. The processes involved in these two studies are pertinent to a number of technologically and biologically important processes. [copyright]American Institute of Physics

Drickamer, H.G.; Lang, J.M.; Dreger, Z.A. (Department of Chemical Engineering, University of Illinois, 1209 W. California Street, Urbana, Illinois 61801 (United States))

1994-07-10T23:59:59.000Z

187

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

E-Print Network (OSTI)

analysis is shown in table 3. Tab.3 Calculation results of direct return system terminal control j i 1 2 3 4 5 Yi 1 0 1 1 1 1 0 2 0.965 0 1 1 1 0.009 3 0.841 0.863 0 1 1 0.074 4 0.873 0.900 0.955 0 1 0.068 5 0.797 0.821 0.872 0.913 0 0.149 j... analysis is shown in table 3. Tab.3 Calculation results of direct return system terminal control j i 1 2 3 4 5 Yi 1 0 1 1 1 1 0 2 0.965 0 1 1 1 0.009 3 0.841 0.863 0 1 1 0.074 4 0.873 0.900 0.955 0 1 0.068 5 0.797 0.821 0.872 0.913 0 0.149 j...

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

2006-01-01T23:59:59.000Z

188

Canonical rotation variables and non-Hamiltonian forces: solar radiation pressure effects on asteroid rotation  

Science Journals Connector (OSTI)

......the effects by absorbed solar photons on the rotation...drawn. At last, if the solar photons are not absorbed...induced by inelastic energy dissipation for subkilometre...specular reflection of solar photons on Eros' surface...Research Council of Norway, projects 153382 and 170870. REFERENCES......

E. Mysen

2006-11-01T23:59:59.000Z

189

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

190

Instability of a spherical gas bubble in a variable-pressure field  

Science Journals Connector (OSTI)

Only a few studies, of which we mention [1–5], have been addressed to the problem of the stability of the accelerated motion of a spherical ... present paper we consider the problem of the stability of radial mot...

E. M. Chernykh

191

A Timoshenko beam theory with pressure corrections for layered orthotropic beams  

E-Print Network (OSTI)

A Timoshenko beam theory with pressure corrections for layered orthotropic beams Graeme J. Kennedya of Michigan, Ann Arbor, MI 48109, USA Abstract A Timoshenko beam theory for layered orthotropic beams and rotation variables that provide the kinematic description of the beam, stress and strain moments used

Papalambros, Panos

192

Electrical Characterization of an RF Glow Discharge at Room Pressure  

SciTech Connect

A non-thermal atmospheric-like plasma source able to operate at room temperature represents, by its physical nature, a considerable potential for biological applications, given its highly accurate action and extremely controllable penetration on the surface of biological tissue. As we start up a research line into this technology, we report the electrical characterization of a room pressure plasma discharge by means of a coupling network model. The discharge is produced by a 13.56MHz commercial generator. As it is impossible to measure directly its state variables (voltage and current intensity) due to the considerable perturbation created by introducing a low impedance at the system output, then an indirect estimation of such variables is achieved from experimental diagnostics at the input, so to validate the proposed electrical model.

Perez-Martinez, J. A.; Piedad-Beneitez, A. de la [Instituto Tecnologico de Toluca, AP 890, Toluca (Mexico); Pena-Eguiluz, R.; Mercado-Cabrera, A.; Valencia A, R.; Barocio, S. R. [Instituto Nacional de Investigaciones Nucleares, AP 18-1027, 11801, Mexico D.F. (Mexico); Lopez-Callejas, R.; Godoy-Cabrera, O. G.; Benitez-Read, J. S.; Pacheco-Sotelo, J. O. [Instituto Tecnologico de Toluca, AP 890, Toluca (Mexico); Instituto Nacional de Investigaciones Nucleares, AP 18-1027, 11801, Mexico D.F. (Mexico)

2006-12-04T23:59:59.000Z

193

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

194

Variable frequency microwave heating apparatus  

DOE Patents (OSTI)

A variable frequency microwave heating apparatus (10) designed to allow modulation of the frequency of the microwaves introduced into a multi-mode microwave cavity (34) for testing or other selected applications. The variable frequency microwave heating apparatus (10) includes a microwave signal generator (12) and a high-power microwave amplifier (20) or a high-power microwave oscillator (14). A power supply (22) is provided for operation of the high-power microwave oscillator (14) or microwave amplifier (20). A directional coupler (24) is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity (34). A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN); Johnson, Arvid C. (Lake in the Hills, IL); Thigpen, Larry T. (Angier, NC)

1999-01-01T23:59:59.000Z

195

Chapter Seven - Variable speed drives  

Science Journals Connector (OSTI)

Publisher Summary The electromechanical controllers are a kind of variable speed drives (VSDs) that are obsolete but are still in use because when a motor and a drive is combined, they become a power drive system (PDS). There are two ways of varying the speed of an induction motor, either by varying the motor slip or by varying the supply frequency. The preferred practice for electrical speed variation is to change the supply frequency with a variable frequency drive (VFD). Many other designs also have been developed. However, except the specialized applications, few are still in operation. A number of motor and drive manufacturers are now producing the integrated motor/VFD units. These units consist of a motor and a specially designed VFD, produced as a single package, with the VFD unit mounted variously on the top, side, or end of the motor.

Europump; Hydraulic Institute

2005-01-01T23:59:59.000Z

196

Impacts of static pressure set level on HVAC energy consumption and indoor conditions  

SciTech Connect

Air static pressure must be maintained at a certain level leaving the air-handling 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 (CV) system, (2) a malfunctioning control device in a variable-air-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 appropriate mixing of hot and cold air for dual-duct systems, excessive reheat in single-duct systems, and an excessive amount of air entering the space. Consequently, the actual fan power and 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 proposed to control the hot duct pressure and the variable-frequency drives (VFDs) to control the fan static, i.e., the cold duct pressure for dual-duct air-handling units. Both a theoretical analysis and results from a case study are presented in this paper.

Liu, M.; Zhu, Y.; Claridge, D.E. [Texas A and M Univ., College Station, TX (United States). Energy Systems Lab.; White, E. [UTMB, Galveston, TX (United States). Energy Management Operation

1997-12-31T23:59:59.000Z

197

Plasma pressure compaction of nanodiamond  

Science Journals Connector (OSTI)

Detonation synthesized nanodiamond (ND) was sintered using a Plasma Pressure Compaction (P2C) technique. Sintering was performed for 1 min at temperatures between 700 and 1200 °C, and for 1–10 min at 900 °C under 65 MPa pressure. Structure and composition of the sintered samples were analyzed by X-ray diffraction, transmission electron microscopy and Raman microspectroscopy. The selected sintering conditions prevent excessive graphitization of diamond and allow formation of porous pellets having the density of 1.3–1.6 g/cm3, hardness > 0.1 GPa and Young's modulus > 3 GPa. The sintered ND pellets with porosity of about 50% have mechanical properties sufficient for handling and can be infiltrated to produce ND composites.

Sebastian Osswald; Adrian Gurga; Franklyn Kellogg; Kyu Cho; Gleb Yushin; Yury Gogotsi

2007-01-01T23:59:59.000Z

198

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

199

Review of Probability Random Variable  

E-Print Network (OSTI)

at close 4) Height of wheel going over a rocky road #12;3 Random Variable Non-examples 1) `Heads' or `Tails' on coin 2) Red or Black ball from urn But we can make these into RV's Basic Idea ­ don't know · Temperature · Wheel height #12;5 Given Continuous RV X... What is the probability that X = x0 ? Oddity : P

Fowler, Mark

200

Anaesthetic machine pipeline inlet pressure gauges do not always measure pipeline pressure  

Science Journals Connector (OSTI)

Some anaesthetic gas machines have pipeline inlet pressure gauges which indicate the higher of either pipeline pressure, or machine circuit pressure (the ... specific circumstances lead to a delayed appreciation ...

Douglas B. Craig; John Longmuir

1980-09-01T23:59:59.000Z

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.


201

Atmospheric-pressure plasma jet  

SciTech Connect

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

Selwyn, G.S.

1999-10-05T23:59:59.000Z

202

Electrical Transport Experiments at High Pressure  

SciTech Connect

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

203

Flash High-Pressure Condensate to Regenerate Low-Pressure Steam  

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

This tip sheet outlines optimal conditions for flashing high-pressure condensate to regenerate low-pressure steam in steam systems.

204

High-Pressure Tube Trailers and Tanks  

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

Presentation on High-Pressure Tube Trailers and Tanks for the DOE Hydrogen Delivery High-Pressure Tanks and Analysis Project Review Meeting held February 8-9, 2005 at Argonne National Laboratory

205

Managed pressure drilling techniques and tools  

E-Print Network (OSTI)

these problems, the economics of drilling the wells will improve, thus enabling the industry to drill wells that were previously uneconomical. Managed pressure drilling (MPD) is a new technology that enables a driller to more precisely control annular pressures...

Martin, Matthew Daniel

2006-08-16T23:59:59.000Z

206

International Hydrogen Fuel and Pressure Vessel Forum  

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

The U.S. Department of Energy (DOE) and Tsinghua University in Beijing co-hosted the International Hydrogen Fuel and Pressure Vessel Forum on September 27–29, 2010 in Beijing, China. High pressure...

207

Air separation with temperature and pressure swing  

DOE Patents (OSTI)

A chemical absorbent air separation process is set forth which uses a temperature swing absorption-desorption cycle in combination with a pressure swing wherein the pressure is elevated in the desorption stage of the process.

Cassano, Anthony A. (Allentown, PA)

1986-01-01T23:59:59.000Z

208

Pressure Data: BOP Summary 28 May 2010  

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

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

209

Nanocomposite Flexible Pressure Sensor for Biomedical Applications  

E-Print Network (OSTI)

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

Fachin, F.

210

Carbon nanotube temperature and pressure sensors  

DOE Patents (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

211

High pressure fiber optic sensor system  

DOE Patents (OSTI)

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

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

2013-11-26T23:59:59.000Z

212

Neutron scattering studies of materials under pressure  

Science Journals Connector (OSTI)

A review of experimental techniques used in the study of materials under applied pressure by neutron scattering is given along with a discussion of the amount of information that can be obtained from various pressure conditions. Some experimental results are presented to illustrate both the feasibility and the interest of elastic and inelastic neutron scattering measurements of materials under pressure.

C. Vettier

1982-01-01T23:59:59.000Z

213

A group bridge approach for variable selection  

Science Journals Connector (OSTI)

......group bridge approach for variable...Actuarial Science, University...Department of Management Science, University...group bridge approach that is capable...group bridge approach for variable...Actuarial Science, University...Department of Management Science......

Jian Huang; Shuange Ma; Huiliang Xie; Cun-Hui Zhang

2009-06-01T23:59:59.000Z

214

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)

215

Variable frequency microwave furnace system  

DOE Patents (OSTI)

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

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

1994-01-01T23:59:59.000Z

216

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

217

Instantaneous Measurement of Nonlocal Variables Lev Vaidman  

E-Print Network (OSTI)

Instantaneous Measurement of Nonlocal Variables Lev Vaidman 1 School of Physics and Astronomy variables related to two or more separate sites can be measured instantaneously, except for a finite time of the measurement. It is a verification measurement: it yields reliably the eigenvalues of the nonlocal variables

Vaidman, Lev

218

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

2008-06-10T23:59:59.000Z

219

Asphaltene-Induced Precipitation and Deposition During Pressure Depletion on a Porous Medium: An Experimental Investigation and Modeling Approach  

Science Journals Connector (OSTI)

The SDS consists of a mercury-free, variable volume, fully visual PVT cell equipped with fiber optics light transmission probes (source and detection) to measure the onset of organic solids precipitation (due to temperature, pressure, and compositional change) concurrently with fluid volumetric data. ... Schematic diagram of phase behavior system of reservoir fluid for mercury-free operation. ... The equipment used for this investigation was a mercury-free, variable vol., fully visual JEFRI-DBR PVT system with laser light scattering. ...

José L. Mendoza de la Cruz; Francisco J. Argüelles-Vivas; Víctor Matías-Pérez; Cecilia de los A. Durán-Valencia; Simón López-Ramírez

2009-10-01T23:59:59.000Z

220

System for pressure letdown of abrasive slurries  

DOE Patents (OSTI)

A system and method for releasing erosive slurries from containment at high pressure without subjecting valves to highly erosive slurry flow. The system includes a pressure letdown tank disposed below the high-pressure tank, the two tanks being connected by a valved line communicating the gas phases and a line having a valve and choke for a transfer of liquid into the letdown tank. The letdown tank has a valved gas vent and a valved outlet line for release of liquid. In operation, the gas transfer line is opened to equalize pressure between tanks so that a low level of liquid flow occurs. The letdown tank is then vented, creating a high-pressure differential between the tanks. At this point, flow between tanks is controlled by the choke. High-velocity, erosive flow through a high-pressure outlet valve is prevented by equalizing the start up pressure and thereafter limiting flow with the choke.

Kasper, Stanley (Pittsburgh, PA)

1991-01-01T23:59:59.000Z

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.


221

Passive tire pressure sensor and method  

DOE Patents (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

222

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....

223

Modeling and Experimental Investigation of a Variable Speed Drive Water Source Heat Pump  

Science Journals Connector (OSTI)

Accurate variable speed characteristics are needed for water source heat pumps (WSHP) to design variable speed controls to adjust refrigerant flow rates in heat pumps and air conditioners. The system capacity can then be regulated to match the compressor loads to the heating or cooling needs to improve the energy efficiency and lower energy costs. The motor and compression characteristics of WSHP were modeled to include the coupling between the motor speed and the torque characteristics and compression characteristics. An analytical model is given for a variable speed hermetic scroll compressor that describes various factors, such as the drive frequency, suction pressure, and discharge pressure as a function of the compressor speed. The model was validated experimentally using R22 and \\{R134a\\} in an experimental WSHP with variable speed control using frequency conversion. The results show that the analytical model properly describes the variable speed characteristics and provides a control strategy for adjusting the capacity of scroll compressors to match the heat pump or air conditioner operating conditions.

Zhifang Xue; Lin Shi

2010-01-01T23:59:59.000Z

224

Variable White Dwarf Data Tables  

SciTech Connect

Below, I give a brief explanation of the information in these tables. In all cases, I list the WD {number_sign}, either from the catalog of McCook {ampersand} Sion (1987) or determined by me from the epoch 1950 coordinates. Next, I list the most commonly used name (or alias), then I list the variable star designation if it is available. If not, I list the constellation name and a V** or?? depending on what the last designated variable star for that constellation is. I present epoch 2000 coordinates for all of the stars, which I precessed from the 1950 ones in most cases. I do not include proper motion effects; this is negligible for all except the largest proper motion DAV stars, such as L 19-2, BPM 37093, B 808, and G 29-38. Even in these cases, the error is no more than 30` in declination and 2 s in right ascension. I culled effective temperatures from the latest work (listed under each table); they are now much more homogeneous than before. I pulled the magnitude estimates from the appropriate paper, and they are mean values integrated over several cycles. The amplitude given is for the height of a typical pulse in the light curve. The periods correspond the dominant ones found in the light curve. In some cases, there is a band of power in a given period range, or the light curve is very complex, and I indicate this in the table. In the references, I generally list the paper with the most comprehensive pulsation analysis for the star in question. In some cases, there is more than one good reference, and I list them as well.

Bradley, P. A.

1997-12-31T23:59:59.000Z

225

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.

Khan, M. Rashid (Morgantown, WV)

1990-01-01T23:59:59.000Z

226

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

227

On the correction of conserved variables for numerical RMHD with staggered constrained transport  

E-Print Network (OSTI)

Despite the success of the combination of conservative schemes and staggered constrained transport algorithms in the last fifteen years, the accurate description of highly magnetized, relativistic flows with strong shocks represents still a challenge in numerical RMHD. The present paper focusses in the accuracy and robustness of several correction algorithms for the conserved variables, which has become a crucial ingredient in the numerical simulation of problems where the magnetic pressure dominates over the thermal pressure by more than two orders of magnitude. Two versions of non-relativistic and fully relativistic corrections have been tested and compared using a magnetized cylindrical explosion with high magnetization ($ \\ge 10^4$) as test. In the non-relativistic corrections, the total energy is corrected for the difference in the classical magnetic energy term between the average of the staggered fields and the conservative ones, before (CA1) and after (CA1') recovering the primitive variables. These c...

Martí, José M

2015-01-01T23:59:59.000Z

228

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

229

Pressure maintenance in a volatile oil reservoir  

E-Print Network (OSTI)

reservoir. Historically, produced and makeup gas was injected to maintain pressure. In today's economy. gas has an increasing market value compared to the price of oil. Therefore, it becomes increasingly difficult to justify economically the injection... of produced gas and the purchase of additional make up gas to maintain reservoir pressure. Accordingly, water injection to maintain pressure becomes more favorable economically. This research investigated water injection into a volatile oil reservoir...

Schuster, Bruce Alan

2012-06-07T23:59:59.000Z

230

Dynamic pore pressure ahead of the bit  

SciTech Connect

An analytic approach is presented in an attempt to improve the understanding of the mechanism of pore-pressure invasion ahead of the bit during drilling. An axisymmetric model accounts for a zone of damaged permeability (skin) on the work front. The effect of rate of penetration (ROP) and rotation speed on the pore pressure at the depth of cut is significant in the lower range of permeabilities, while for the high permeabilities, the skin has an overwhelming control on the pressure invasion.

Peltier, B.; Atkinson, C.

1987-12-01T23:59:59.000Z

231

Electrical resistance of Evanohm under pressure  

Science Journals Connector (OSTI)

The electrical resistance of Evanohm wire has been determined as a function of hydrostatic pressure. A Teflon cell with a novel type of electrical feedthrough was used to contain the fluid medium. The resistance was found to decrease approximately linearly by 0.3% up to 27 kilobar. The remarkably small variation of its resistance with temperature and pressure makes Evanohm a suitable material for strain measurements under pressure.

P. Andersson; G. Bäckström

1975-01-01T23:59:59.000Z

232

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

233

Effect of pressure anisotropy on magnetorotational instability  

SciTech Connect

It is shown that two new instabilities of hybrid type can occur in a rotating magnetized plasma with anisotropic pressure, i.e., the rotational firehose instability and the rotational mirror instability. In the case of {beta}{sub parallel} > {beta}{sub perpendicular}, where {beta}{sub parallel} and {beta}{sub -perpendicular} are the ratios of the parallel and perpendicular plasma pressure to the magnetic field pressure, the pressure anisotropy tends to suppress both new instabilities; in the case {beta}{sub perpendicular} > {beta}{sub parallel}, it leads to their strengthening. In the latter case, the perturbations considered can be unstable even if the Velikhov instability criterion is not satisfied.

Mikhailovskii, A. B. [Russian Research Centre Kurchatov Institute, Institute of Nuclear Fusion (Russian Federation); Lominadze, J. G. [Georgian National Astrophysical Observatory (United States)], E-mail: j.lominadze@astro-ge.org; Churikov, A. P. [Syzran Branch of Samara Technical University (Russian Federation); Erokhin, N. N. [Russian Research Centre Kurchatov Institute, Institute of Nuclear Fusion (Russian Federation); Erokhin, N. S. [Russian Academy of Sciences, Space Research Institute (Russian Federation); Tsypin, V. S

2008-02-15T23:59:59.000Z

234

Viscosity of liquid Fe at high pressure  

Science Journals Connector (OSTI)

Synchrotron x-ray radiography has been used to measure the viscosity of pure liquid Fe at high pressure and temperature in a large volume press. A probe sphere rising through liquid Fe at high pressure and temperature is imaged, in situ, allowing for the derivation of sample viscosity through a modified form of Stokes’ equation. The effect of pressure on viscosity is fit by the semi empirical framework for transport coefficients in liquid metals, providing experimental verification of constant viscosity at the pressure-dependent melting temperature of liquid Fe where no change in liquid structure occurs.

Michael D. Rutter; Richard A. Secco; Hongjian Liu; Takeyuki Uchida; Mark L. Rivers; Stephen R. Sutton; Yanbin Wang

2002-08-14T23:59:59.000Z

235

Putting the pressure on carbon dioxide | EMSL  

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

Putting the pressure on carbon dioxide Improving the chances for fuel recovery and carbon sequestration Artwork from this research graces the cover of Environmental Science...

236

High-Pressure Tube Trailers and Tanks  

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

bending stress: continuous fiber vessels and vessels made of replicants Conformable tanks require internal stiffeners (ribs) to efficiently support the pressure and minimize...

237

Alternative Strategies for Low Pressure End Uses  

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

This tip sheet outlines alternative strategies for low-pressure end uses as a pathway to reduced compressed air energy costs.

238

Atmospheric Pressure Discharges: Traveling Wave Plasma Sources  

Science Journals Connector (OSTI)

Microwave sustained, atmospheric pressure plasmas are finding an increasing number of applications ... interest in the developing and investigating of appropriate plasma sources [1, 2].

Z. Zakrzewski; M. Moisan

1999-01-01T23:59:59.000Z

239

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

240

Geothermal: Sponsored by OSTI -- Reservoir Pressure Management  

Office of Scientific and Technical Information (OSTI)

Reservoir Pressure Management Geothermal Technologies Legacy Collection HelpFAQ | Site Map | Contact Us | Admin Log On HomeBasic Search About Publications Advanced Search New Hot...

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

High-Pressure Model Catalyst System | EMSL  

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

of one atmosphere or below in a reactor situated just below an ultra-high vacuum (UHV) chamber. In particular, heterogeneous catalytic reactions at realistic pressures over...

242

Documentation Requirements for Pressurized Experiment Equipment  

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

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...

243

Heating tar sands formations while controlling pressure  

DOE Patents (OSTI)

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

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

2010-01-12T23:59:59.000Z

244

Variable path length spectrophotometric probe  

DOE Patents (OSTI)

A compact, variable pathlength, fiber optic probe for spectrophotometric measurements of fluids in situ. The probe comprises a probe body with a shaft having a polished end penetrating one side of the probe, a pair of optic fibers, parallel and coterminous, entering the probe opposite the reflecting shaft, and a collimating lens to direct light from one of the fibers to the reflecting surface of the shaft and to direct the reflected light to the second optic fiber. The probe body has an inlet and an outlet port to allow the liquid to enter the probe body and pass between the lens and the reflecting surface of the shaft. A linear stepper motor is connected to the shaft to cause the shaft to advance toward or away from the lens in increments so that absorption measurements can be made at each of the incremental steps. The shaft is sealed to the probe body by a bellows seal to allow freedom of movement of the shaft and yet avoid leakage from the interior of the probe.

O'Rourke, Patrick E. (157 Greenwood Dr., Martiney, GA 30907); McCarty, Jerry E. (104 Recreation Dr., Aiken, SC 29803); Haggard, Ricky A. (1144 Thornwood Drive, North Augusta, SC 29891)

1992-01-01T23:59:59.000Z

245

HERSCHEL OBSERVATIONS OF CATACLYSMIC VARIABLES  

SciTech Connect

We have used the PACS instrument on the Herschel Space Observatory to observe eight cataclysmic variables at 70 and 160 {mu}m. Of these eight objects, only AM Her was detected. We have combined the Herschel results with ground-based, Spitzer, and WISE observations to construct spectral energy distributions for all of the targets. For the two dwarf novae in the sample, SS Cyg and U Gem, we find that their infrared luminosities are completely dominated by their secondary stars. For the two highly magnetic 'polars' in our survey, AM Her and EF Eri, we find that their mid-infrared excesses, previously attributed to circumbinary dust emission, can be fully explained by cyclotron emission. The WISE light curves for both sources show large, orbitally modulated variations that are identically phased to their near-IR light curves. We propose that significant emission from the lowest cyclotron harmonics (n {<=} 3) is present in EF Eri and AM Her. Previously, such emission would have been presumed to be optically thick, and not provide significant orbitally modulated flux. This suggests that the accretion onto polars is more complicated than assumed in the simple models developed for these two sources. We develop a model for the near-/mid-IR light curves for WZ Sge with an L2 donor star that shows that the ellipsoidal variations from its secondary star are detected. We conclude that none of the targets surveyed have dusty circumbinary disks.

Harrison, Thomas E.; Hamilton, Ryan T. [Department of Astronomy, New Mexico State University, Box 30001, MSC 4500, Las Cruces, NM 88003-8001 (United States); Tappert, Claus [Departamento de Fisica y Astronomia, Universidad de Valparaiso, Avda. Gran Bretana 1111, Valparaiso (Chile); Hoffman, Douglas I. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Campbell, Ryan K., E-mail: tharriso@nmsu.edu, E-mail: rthamilt@nmsu.edu, E-mail: claus.tappert@uv.cl, E-mail: dhoffman@ipac.caltech.edu, E-mail: Ryan.Campbell@humobldt.edu [Department of Physics and Astronomy, Humboldt State University, 1 Harpst St., Arcata, CA 95521 (United States)

2013-01-01T23:59:59.000Z

246

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

247

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

248

Pressure analysis for horizontal wells  

SciTech Connect

This paper presents horizontal-well test design and interpretation methods. Analytical solutions are developed that can be handled easily by a desktop computer to carry out design as well as interpretation with semilog and log-log analysis. These analytical solutions point out the distinctive behavior of horizontal wells: (1) at early time, there is a circular radial flow in a vertical plane perpendicular to the well, and (2) at late time, there is a horizontal pseudoradial flow. Each type of flow is associated with a semilog straight line to which semilog analysis has to be adapted. The horizontal pseudoradial flow takes into account a pseudoskin depending on system geometry, which is a priori defined and estimated. Practical time criteria are proposed to determine the beginning and the end of each type of flow and to provide a guide to semilog analysis and well test design. The authors study the behavior of uniform-flux or infinite-conductivity horizontal wells, with wellbore storage and skin. The homogeneous reservoir is infinite or limited by impermeable or constant-pressure boundaries. A method is also outlined to transform all our solutions for homogeneous reservoirs into corresponding solutions for double-porosity reservoirs.

Davlau, F.; Mouronval, G.; Bourdarot, G.; Curutchet, P.

1988-12-01T23:59:59.000Z

249

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

250

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

251

Variable-Period Undulators for Synchrotron Radiation  

SciTech Connect

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

252

Multivector Functions of a Real Variable  

E-Print Network (OSTI)

This paper is an introduction to the theory of multivector functions of a real variable. The notions of limit, continuity and derivative for these objects are given. The theory of multivector functions of a real variable, even being similar to the usual theory of vector functions of a real variable, has some subtle issues which make its presentation worhtwhile.We refer in particular to the derivative rules involving exterior and Clifford products, and also to the rule for derivation of a composition of an ordinary scalar function with a multivector function of a real variable.

A. M. Moya; V. V. Fernández; W. A. Rodrigues Jr

2002-12-17T23:59:59.000Z

253

Hybrid Bayesian Networks with Linear Deterministic Variables  

E-Print Network (OSTI)

Conference (UAI-05), 2005, AUAI Press, Arlington, VA. 136 Y X Z Figure 2: A Bayesian Network Representation of the Mixed Distribution for X. this example, Y is a discrete variable with state space ? Y = {1,2,3}, Z is a real-valued variable, and X is a... conditionally deterministic variable whose condi- tional distribution is described as follows: X |{y,z} = y if y =1,2 and X |{y,z} = z if y =3. Potentials of the type described above are used in this paper to represent distributions of variables in hy- brid...

Cobb, Barry R.; Shenoy, Prakash P.

2005-07-01T23:59:59.000Z

254

Integrating Variable Renewable Energy: Challenges and Solutions  

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

Integrating Variable Renewable Energy: Challenges and Solutions L. Bird, M. Milligan, and D. Lew National Renewable Energy Laboratory Technical Report NRELTP-6A20-60451 September...

255

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

256

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 +

257

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 +

258

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 +

259

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 +

260

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 +

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

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 +

262

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 +

263

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

264

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

E-Print Network (OSTI)

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

Richardson, Kyle Wade

2009-05-15T23:59:59.000Z

265

Thermal expansion of Mg(OH)2 brucite under high pressure and pressure dependence of entropy  

Science Journals Connector (OSTI)

An equation of state for Mg(OH)2 brucite under high-pressure and high-temperature conditions ... -ray diffraction. Pressure dependence of entropy of brucite has been calculated with thermal expansion coefficient....

H. Fukui; O. Ohtaka; T. Suzuki; K. Funakoshi

2003-10-01T23:59:59.000Z

266

Comparison of POLDER Apparent and Corrected Oxygen Pressure to ARM/MMCR Cloud Boundary Pressures  

SciTech Connect

POLDER (POLarization and Directionality of the Earth’s Reflectances) cloud oxygen pressures are compared to cloud boundary pressures obtained from the combination of Lidar and Millimeter Wave Cloud Radar ground measurements located at the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site. Without ground reflection correction, the apparent pressures are found to be closer to the mean cloud pressure than to the cloud top pressure. Nevertheless, for almost a quarter of our comparison cases the apparent pressure level is found to be below the cloud base level. This problem practically disappears applying a simple correction for the surface reflection effect. The corrected oxygen pressures are then found to be very close (12 hPa on average) to the mean cloud pressure.

Vanbauce, Claudine; Cadet, Bertrand; Marchand, Roger T.

2003-03-06T23:59:59.000Z

267

Statistics of pressure and of pressure-velocity correlations in isotropic turbulence  

E-Print Network (OSTI)

Some pressure and pressure-velocity correlation in a direct numerical simulations of a three-dimensional turbulent flow at moderate Reynolds numbers have been analyzed. We have identified a set of pressure-velocity correlations which posseses a good scaling behaviour. Such a class of pressure-velocity correlations are determined by looking at the energy-balance across any sub-volume of the flow. According to our analysis, pressure scaling is determined by the dimensional assumption that pressure behaves as a ``velocity squared'', unless finite-Reynolds effects are overwhelming. The SO(3) decompositions of pressure structure functions has also been applied in order to investigate anisotropic effects on the pressure scaling.

L. Biferale; P. Gualtieri; F. Toschi

2000-01-17T23:59:59.000Z

268

Spectral Variability from the Patchy Atmospheres of T and Y Dwarfs  

E-Print Network (OSTI)

Brown dwarfs of a variety of spectral types have been observed to be photometrically variable. Previous studies have focused on objects at the L/T transition, where the iron and silicate clouds in L dwarfs break up or dissipate. However, objects outside of this transitional effective temperature regime also exhibit variability. Here, we present models for mid-late T dwarfs and Y dwarfs. We present models that include patchy salt and sulfide clouds as well as water clouds for the Y dwarfs. We find that for objects over 375 K, patchy cloud opacity would generate the largest amplitude variability within near-infrared spectral windows. For objects under 375 K, water clouds also become important and generate larger amplitude variability in the mid-infrared. We also present models in which we perturb the temperature structure at different pressure levels of the atmosphere to simulate hot spots. These models show the most variability in the absorption features between spectral windows. The variability is strongest a...

Morley, Caroline V; Fortney, Jonathan J; Lupu, Roxana

2014-01-01T23:59:59.000Z

269

ADAPTIVE ROBUST TRACKING CONTROL OF PRESSURE  

E-Print Network (OSTI)

accuracy of pressure trajectory in the chamber when the pneumatic cylinder is moving. Off-line fitting, it is necessary to utilize the adaptive model compensation for improving the tracking accuracy of pressure and attenuation in pneumatic lines, valve dynamics, flow nonlinearities through the valve orifice, piston friction

Yao, Bin

270

Superconducting high-pressure phases of disilane  

Science Journals Connector (OSTI)

...Superconducting high-pressure phases of disilane 10.1073/pnas.1005242107 Xilian...DC 20015 High-pressure structures of disilane (Si2H6) are investigated extensively...linear-response calculations for Pm-3m disilane at 275 GPa show a large electron-phonon...

Xilian Jin; Xing Meng; Zhi He; Yanming Ma; Bingbing Liu; Tian Cui; Guangtian Zou; Ho-kwang Mao

2010-01-01T23:59:59.000Z

271

NETL- High-Pressure Combustion Research Facility  

SciTech Connect

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

None

2013-07-08T23:59:59.000Z

272

September 25, 2006 Experimental pressure solution compaction  

E-Print Network (OSTI)

September 25, 2006 Experimental pressure solution compaction of synthetic halite/calcite aggregates by addition of hard particles. Sieved mixtures of calcite and halite grains are experimentally compacted in drained pressure cells in the presence of a saturated aqueous solution. The individual halite grains

Paris-Sud XI, Université de

273

NETL- High-Pressure Combustion Research Facility  

ScienceCinema (OSTI)

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

None

2014-06-26T23:59:59.000Z

274

Investigation on the solidification of several pure cyclic and aromatic hydrocarbons at pressures to 300 MPa  

SciTech Connect

The effect of pressure on the solidification of several saturated cyclic hydrocarbons and three xylene isomers are experimentally determined with a variable-volume view cell at pressures to 300 MPa and temperatures starting at 293.15 K. Solid–liquid transitions are observed for cyclooctane, cis-1,2-dimethylcyclohexane, trans-1,4-dimethylcyclohexane, p-xylene, o-xylene, and 2-methylnaphthalene. However, methylcyclohexane, ethylcyclohexane, cis-1,4-dimethylcyclohexane, and m-xylene remained liquid over the same operating pressure and temperature ranges. The experimental solid–liquid transition data are well represented with two empirical equations, the Simon equation and a 2nd-order polynomial equation. Data obtained in this study agree with literature data within ±0.4% for 2-methylnaphthalene and ±0.2% for p-xylene.

Wu, Yue; Liu, Kun; Bamgbade, Babatunde A.; McHugh, Mark A.

2013-09-01T23:59:59.000Z

275

Method for continuous control of composition and doping of pulsed laser deposited films by pressure control  

DOE Patents (OSTI)

A method for growing a deposit upon a substrate of semiconductor material involves the utilization of pulsed laser deposition techniques within a low-pressure gas environment. The substrate and a target of a first material are positioned within a deposition chamber and a low-pressure gas atmosphere is developed within the chamber. The substrate is then heated, and the target is irradiated, so that atoms of the target material are ablated from the remainder of the target, while atoms of the gas simultaneously are adsorbed on the substrate/film surface. The ablated atoms build up upon the substrate, together with the adsorbed gas atoms to form the thin-film deposit on the substrate. By controlling the pressure of the gas of the chamber atmosphere, the composition of the formed deposit can be controlled, and films of continuously variable composition or doping can be grown from a single target of fixed composition.

Lowndes, Douglas H. (Knoxville, TN); McCamy, James W. (Knoxville, TN)

1996-01-01T23:59:59.000Z

276

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

277

Deutsch-Jozsa algorithm for continuous variables  

E-Print Network (OSTI)

We present an idealized quantum continuous variable analog of the Deutsch-Jozsa algorithm which can be implemented on a perfect continuous variable quantum computer. Using the Fourier transformation and XOR gate appropriate for continuous spectra we show that under ideal operation to infinite precision that there is an infinite reduction in number of query calls in this scheme.

Arun K. Pati; Samuel L. Braunstein

2002-07-18T23:59:59.000Z

278

The Galex Ultraviolet Variability (GUVV) Catalog  

E-Print Network (OSTI)

We present Version 1.0 of the NASA Galaxy Evolution Explorer (GALEX) ultraviolet variability catalog (GUVV) that contains information on 84 time-variable and transient sources gained with simultaneous near and far ultraviolet photometric observations. These time-variable sources were serendipitously revealed in the various 1.2 degree star fields currently being surveyed by the GALEX satellite in two ultraviolet bands (NUV 1750-2750A, FUV 1350-1750A) with limiting AB magnitudes of 23-25. The largest-amplitude variable objects presently detected by GALEX are M-dwarf flare stars, which can brighten by 5-10 mag in both the NUV and FUV bands during short duration (< 500s) outbursts. Other types of large-amplitude ultraviolet variable objects include ab-type RR Lyrae stars, which can vary periodically by 2-5mag in the GALEX FUV band. This first GUVV catalog lists galactic positions and possible source identifications in order to provide the astronomical community with a list of time-variable objects that can now be repeatedly observed at other wavelengths. We expect the total number of time-variable source detections to increase as the GALEX mission progresses, such that later version numbers of the GUVV catalog will contain substantially more variable sources.

Barry Y. Welsh; Jonathan M. Wheatley; Kenneth Heafield; Mark Seibert; Stanley E. Browne; Samir Salim; R. Michael Rich; Tom A. Barlow; Luciana Bianchi; Yong-Ik Byun; Jose Donas; Karl Forster; Peter G. Friedman; Timothy M. Heckman; Patrick N. Jelinsky; Young-Wook Lee; Barry F. Madore; Roger F. Malina; D. Christopher Martin; Bruno Milliard; Patrick Morrissey; Susan G. Neff; David Schiminovich; Oswald H. W. Siegmund; Todd Small; Alex S. Szalay; Ted K. Wyder

2005-04-21T23:59:59.000Z

279

Quantum Computing and Hidden Variables Scott Aaronson #  

E-Print Network (OSTI)

Quantum Computing and Hidden Variables Scott Aaronson # Institute for Advanced Study, Princeton of a hidden variable, then we could e#ciently solve problems that are believed to be intractable even powerful than the quantum computing model. PACS numbers: 03.65.Ta, 03.65.Ud, 03.67.Lx, 02.70.­c I

Aaronson, Scott

280

Solar Dynamics Observatory/ Extreme Ultraviolet Variability Experiment  

E-Print Network (OSTI)

Solar Dynamics Observatory/ EVE Extreme Ultraviolet Variability Experiment Frequently Asked and model solar extreme ultraviolet irradiance variations due to solar flares, solar rotation, and solar and structure of the Sun. What is solar variability? Solar radiation varies on all time scales ranging from

Mojzsis, Stephen J.

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

Field measurement of lateral earth pressures on retaining walls  

E-Print Network (OSTI)

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

Riggins, Michael

2012-06-07T23:59:59.000Z

282

Initiation Pressure Thresholds from Three Sources  

SciTech Connect

Pressure thresholds are minimum pressures needed to start explosive initiation that ends in detonation. We obtain pressure thresholds from three sources. Run-to-detonation times are the poorest source but the fitting of a function gives rough results. Flyer-induced initiation gives the best results because the initial conditions are the best known. However, very thick flyers are needed to give the lowest, asymptotic pressure thresholds used in modern models and this kind of data is rarely available. Gap test data is in much larger supply but the various test sizes and materials are confusing. We find that explosive pressures are almost the same if the distance in the gap test spacers are in units of donor explosive radius. Calculated half-width time pulses in the spacers may be used to create a pressure-time curve similar to that of the flyers. The very-large Eglin gap tests give asymptotic thresholds comparable to extrapolated flyer results. The three sources are assembled into a much-expanded set of near-asymptotic pressure thresholds. These thresholds vary greatly with density: for TATB/LX-17/PBX 9502, we find values of 4.9 and 8.7 GPa at 1.80 and 1.90 g/cm{sup 3}, respectively.

Souers, P C; Vitello, P

2007-02-28T23:59:59.000Z

283

Pressure Safety Program Implementation at ORNL  

SciTech Connect

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

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

2013-01-01T23:59:59.000Z

284

ASME post construction pressure technology codes  

SciTech Connect

The need to continue to operate pressurized equipment and other facilities in a safe, reliable and cost effective manner has led to the development of many new approaches to in-service inspection, flaw evaluation, and repair. Interest on the part of users, regulatory authorities and others in standardizing these approaches has led to the formation of a new ASME Main Committee on Post Construction under the Board on Pressure Technology Codes and Standards, and a new Division of the Pressure Vessel Research Council on Continued Operation of Equipment. This paper provides a brief overview of these activities.

Sims, J.R. [Exxon Research and Engineering Co., Florham Park, NJ (United States)

1996-12-01T23:59:59.000Z

285

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

286

Pipeline gas pressure reduction with refrigeration generation  

SciTech Connect

The high pressure of pipeline gas is reduced to the low pressure of a distribution system with simultaneous generation of refrigeration by passing the gas through two successive centrifugal compressors driven by two turbo-expanders in which the compressed gas is expanded to successively lower pressures. Refrigeration is recovered from the gas as it leaves each turbo-expander. Methanol is injected into the pipeline gas before it is expanded to prevent ice formation. Aqueous methanol condensate separated from the expanded gas is distilled for the recovery and reuse of methanol.

Markbreiter, S. J.; Schorr, H. P.

1985-06-11T23:59:59.000Z

287

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

288

Effect of pressure anisotropy on magnetorotational instability  

SciTech Connect

It is shown that two new instabilities of hybrid type can occur in a rotating magnetized plasma with anisotropic pressure, i.e., the rotational firehose instability and the rotational mirror instability. In the case of {beta}{sub Parallel-To} > {beta}{sub Up-Tack }, where {beta}{sub Parallel-To} and {beta}{sub Up-Tack} are the ratios of the parallel and perpendicular plasma pressure to the magnetic field pressure, the pressure anisotropy tends to suppress both new instabilities; in the case {beta}{sub Up-Tack} > {beta}{sub Parallel-To }, it leads to their strengthening. In the latter case, the perturbations considered can be unstable even if the Velikhov instability criterion is not satisfied.

Mikhailovskii, A. B. [Russian Research Centre Kurchatov Institute, Institute of Nuclear Fusion (Russian Federation); Lominadze, J. G., E-mail: j.lominadze@astro-ge.org [Georgian National Astrophysical Observatory (United States); Churikov, A. P. [Syzran Branch of Samara Technical University (Russian Federation); Erokhin, N. N. [Russian Research Centre Kurchatov Institute, Institute of Nuclear Fusion (Russian Federation); Erokhin, N. S. [Russian Academy of Sciences, Space Research Institute (Russian Federation); Tsypin, V. S.

2008-02-15T23:59:59.000Z

289

CRAD, Pressurized Systems and Cryogens Assessment Plan  

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

Assure personnel health and safety through regularly scheduled inspections and maintenance on pressure vessels and equipment, compressed gases and gas cylinders, vacuum equipment and systems, hydraulics, and cryogenic materials and systems.

290

Wind pressure distribution on shell structures  

E-Print Network (OSTI)

relates to both cost and safety. This study has revealed that wind pressure criteria for shell structures is not adequately covered by most building codes. Those that do exist are rather vague and sometimes erroneous. One recently published design manual...

Yancey, Kenneth Earl, Jr

1963-01-01T23:59:59.000Z

291

Pulse Pressure Forming of Lightweight Materials, Development...  

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

Merit Review and Peer Evaluation Meeting, June 7-11, 2010 -- Washington D.C. lm015smith2010o.pdf More Documents & Publications Pulse-Pressure Forming of Lightweight Metals...

292

Program predicts two-phase pressure gradients  

SciTech Connect

The calculator program discussed, ORK, was designed for the HP-41CV hand-held calculator and uses the Orkiszewski correlation for predicting 2-phase pressure gradients in vertical tubulars. Accurate predictions of pressure gradients in flowing and gas lift wells over a wide range of well conditions can be obtained with this method, which was developed based on data from 148 wells. The correlation is one of the best generalized 2-phase pressure gradient prediction methods developed to date for vertical flow. It is unique in that hold-up is derived from observed physical phenomena, and the pressure gradient is related to the geometrical distribution of the liquid and gas phase (flow regime).

Jacks, D.C.; Hill, A.D.

1983-11-18T23:59:59.000Z

293

Nanoprobe measurements of materials at megabar pressures  

Science Journals Connector (OSTI)

...Photon Science, SLAC National Accelerator Laboratory, 2575 Sand Hill...Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA...low-pressure, if not a near-vacuum, environment, which is incompatible...Department of Energy, National Nuclear Security Administration...

Lin Wang; Yang Ding; Wenge Yang; Wenjun Liu; Zhonghou Cai; Jennifer Kung; Jinfu Shu; Russell J. Hemley; Wendy L. Mao; Ho-kwang Mao

2010-01-01T23:59:59.000Z

294

Pressure swing adsorption with intermediate product recovery  

SciTech Connect

A pressure swing adsorption process is used to achieve intermediate product recovery by the introduction of a gas displacement step before, simultaneous with or subsequent to pressure equalization between beds of a multi-bed adsorption system. A cocurrent depressurization step is then employed to achieve intermediate product recovery. A portion of said intermediate product or of the more readily adsorbable component recovered from a bed advantageously being employed to provide displacement gas for another bed in the adsorption system.

Fuderer, A.

1985-04-23T23:59:59.000Z

295

PRESSURE OSCILLATION IN RHIC CRYOGENIC SYSTEM.  

SciTech Connect

HORIZONTAL BEAM VIBRATION AROUND 10HZ IN THE RELATIVISTIC HEAVY ION COLLIDER (RHIC) HAVE BEEN IDENTIFIED AND THE POSSIBLE SOURCES TO CAUSE THIS VIBRATION HAVE BEEN INVESTIGATED. TO DETERMINE THE HETIUM PRESSURE OSCILLATIONS AS A POSSIBLE PRIMARY VIBRATION SOURCE, HELIUM PRESSURE MEASUREMENTS WERE CARRIED OUT IN THE FIVE CRYOGENIC TRANSFER LINES AT 2 VALVE BOXES AND 6 LEAD PORTS AT 2 TRIPLET CRYOSTAT FOR BOTH MAGNET RINGS. ADDITIONALLY, COLD MA...

JIA,L.MONTAG,C.TALLERICO,T.HIRZEL,W.NICOLETTI,A.

2003-09-22T23:59:59.000Z

296

Hybrid permanent magnet and variable reluctance generator  

SciTech Connect

This patent describes a hybrid electrical generator. It comprises: a permanent magnet generator having a permanent magnet rotor mounted on a shaft, the permanent magnet generator providing an output voltage over an operating range which falls in response to an increasing electrical load; a variable reluctance generator having a rotor mounted on the shaft with excitation of a stator of the variable reluctance generator being provided from the permanent magnet generator, the variable reluctance generator providing an output voltage which varies in response to an increasing electrical load over an operating range; and a voltage regulator, responsive to combined output voltages of the generators, for controlling the output voltage provided by the variable reluctance generator.

Vaidya, J.; Belanger, D.J.

1990-09-25T23:59:59.000Z

297

Variable Temperature Scanning Probe Microscope | EMSL  

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

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

298

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

299

Steam Pressure Reduction, Opportunities, and Issues  

SciTech Connect

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

300

Buoyancy-generated variable-density turbulence  

SciTech Connect

Both a one-point (engineering) and a two-point (spectral) model are tested against numerical data. Deficiencies in these variable-density models are disucssed and modifications are suggested. Attention is restricted to turbulent interactions of two miscible, incompressible Newtonian fluids of different densities. Departures from the limits of validity of the Boussinesq approximation are examined. Results of the buoyancy-generated turbulence are compared with variable-density model predictions. 3 figs, 6 refs.

Sandoval, D.L. [Los Alamos National Lab., NM (United States)]|[Washington Univ. (United States); Clark, T.T. [Los Alamos National Lab., NM (United States); Riley, J.J. [Washington Univ. (United States)

1996-06-01T23:59:59.000Z

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.


301

Prctica 2. Anlisi descriptiva univariable: variables qualitatives  

E-Print Network (OSTI)

nominal SEXO. Codificada de tipus "numèrica" amb valors 1 i 2. Aquests valors s'etiqueten amb: 1 `Hombre": (1) Seleccionem la variable sexo i la col·loquem al requadre de "Variables". D'aquesta manera obtenim: Frecuencias [Conjunto_de_datos1] C:\\Archivos de programa\\SPSS\\GSS93 reducido.sav Estadísticos sexo Sexo del

Castellana, NatĂ lia

302

Prctica 2. Anlisi descriptiva univariable: variables qualitatives  

E-Print Network (OSTI)

nominal SEXO. Codificada de tipus "numèrica" amb valors 1 i 2. Aquests valors s'etiqueten amb: 1 `Hombre) Seleccionem la variable sexo i la col·loquem al requadre de "Variables". D'aquesta manera obtenim la taula de Estadísticos Sexo del entrevistado 1500 0 2 Válidos Perdidos N Moda sexo Sexo del entrevistado 641 42,7 42,7 42

Castellana, NatĂ lia

303

Design and fabrication of pressure-compensating compliant tubes  

E-Print Network (OSTI)

Different fabrication methods are evaluated for producing pressure-compensating tubes for use in low-pressure drip irrigation systems. Such devices would allow drip irrigation systems to operate at driving pressures much ...

Martin, Ian (Ian P.)

2014-01-01T23:59:59.000Z

304

Apparatus and method for pressure testing closure disks  

DOE Patents (OSTI)

A method and device are described for testing the burst pressure of closure disks which provides high pressure to both sides of a disk and rapidly releases pressure from one side thereof causing a high rate of change of pressure. A hollow notched plug allows the rapid release of pressure upon rupturing. A tensile load is transmitted by a piston in combination with fluid pressure to the hollow notched plug. 5 figs.

Merten, C.W. Jr.

1992-01-21T23:59:59.000Z

305

The viscosity of liquids (a) Normal octanol at atmospheric pressure (b) An equipment for high pressures.  

E-Print Network (OSTI)

??Theories of Liquid Viscosity lead to equations giving the variation of the viscosity with temperature and pressure, but give poor agreement with experimental values, particularly… (more)

De Verteuil, Georges Francois

2012-01-01T23:59:59.000Z

306

Bonfire Tests of High Pressure Hydrogen Storage Tanks | Department...  

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

Bonfire Tests of High Pressure Hydrogen Storage Tanks Bonfire Tests of High Pressure Hydrogen Storage Tanks These slides were presented at the International Hydrogen Fuel and...

307

Bonfire Tests of High Pressure Hydrogen Storage Tanks  

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

Bonfire Tests of High Pressure Hydrogen Storage Tanks International Hydrogen Fuel and Pressure Vessel Forum 2010Beijing, P.R. China September 27, 2010 Bonfire Tests of High...

308

Intense and Highly Energetic Atmospheric Pressure Plasma Jet Arrays.  

E-Print Network (OSTI)

??This thesis documents the efforts taken to produce highly ionized and concentrated atmospheric pressure plasma using an arrayed atmospheric pressure plasma jet (APPJ) system. The… (more)

Furmanski, John

2012-01-01T23:59:59.000Z

309

Ultralight Pressure Regulator for Application in Pneumatic Prostheses:.  

E-Print Network (OSTI)

??Available pressure regulators are considered too heavy for application in pneumatic prostheses. Goal of this paper is developing a lighter pressure regulator adapted for this… (more)

Rob, J.

2012-01-01T23:59:59.000Z

310

International Hydrogen Fuel and Pressure Vessel Forum 2010 Proceedings...  

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

International Hydrogen Fuel and Pressure Vessel Forum 2010 Proceedings International Hydrogen Fuel and Pressure Vessel Forum 2010 Proceedings Proceedings from the forum, which took...

311

Pressure Temperature Log At Glass Buttes Area (DOE GTP) | Open...  

Open Energy Info (EERE)

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

312

Effects of meteorological variables on exergetic efficiency of wind turbine power plants  

Science Journals Connector (OSTI)

This present paper deals with exergy efficiency results of the Wind Turbine Power Plants (WTPPs). Effects of meteorological variables such as air density, pressure difference between state points, humidity, and ambient temperature on exergy efficiency are discussed in a satisfactory way. Some key parameters are given monthly for the three turbines. Exergy efficiency differs from 0.23 to 0.27 while temperature is changing from 268.15 K to 308.15 K with air density 1.368–1.146 (kg/m3). While pressure difference (?P) between inlet and outlet of the turbine differs from 100 to 1100 (Pa), exergy efficiency decreases fairly for different wind speeds. While specific humidity is changing from 0.001 to 0.015 (kgwater/kgdry air), exergy efficiency decreases gently. Generally these meteorological variables are neglected while planning WTPPs, but this neglect can cause important errors in calculations and energy plans. Obtained results indicate that while planning \\{WTPPs\\} meteorological variables must be taken into account.

Omer Baskut; Onder Ozgener; Leyla Ozgener

2010-01-01T23:59:59.000Z

313

The dynamics of variable-density turbulence  

SciTech Connect

The dynamics of variable-density turbulent fluids are studied by direct numerical simulation. The flow is incompressible so that acoustic waves are decoupled from the problem, and implying that density is not a thermodynamic variable. Changes in density occur due to molecular mixing. The velocity field, is in general, divergent. A pseudo-spectral numerical technique is used to solve the equations of motion. Three-dimensional simulations are performed using a grid size of 128{sup 3} grid points. Two types of problems are studied: (1) the decay of isotropic, variable-density turbulence, and (2) buoyancy-generated turbulence in a fluid with large density fluctuations. In the case of isotropic, variable-density turbulence, the overall statistical decay behavior, for the cases studied, is relatively unaffected by the presence of density variations when the initial density and velocity fields are statistically independent. The results for this case are in quantitative agreement with previous numerical and laboratory results. In this case, the initial density field has a bimodal probability density function (pdf) which evolves in time towards a Gaussian distribution. The pdf of the density field is symmetric about its mean value throughout its evolution. If the initial velocity and density fields are statistically dependent, however, the decay process is significantly affected by the density fluctuations. For the case of buoyancy-generated turbulence, variable-density departures from the Boussinesq approximation are studied. The results of the buoyancy-generated turbulence are compared with variable-density model predictions. Both a one-point (engineering) model and a two-point (spectral) model are tested against the numerical data. Some deficiencies in these variable-density models are discussed and modifications are suggested.

Sandoval, D.L.

1995-11-01T23:59:59.000Z

314

Cloud speed impact on solar variability scaling â?? Application to the wavelet variability model  

E-Print Network (OSTI)

Kleissl, J. , 2013. Deriving cloud velocity from an array ofCloud Speed Impact on Solar Variability Scaling -this work, we determine from cloud speeds. Cloud simulator

Lave, Matthew; Kleissl, Jan

2013-01-01T23:59:59.000Z

315

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

316

Cross spectra between temperature and pressure in a constant area duct downstream of a hydrogen fueled combustor  

Science Journals Connector (OSTI)

It was shown in a recent paper [J. H. Miles and E. A. Krejsa J. Acoust. Soc. Am. 72 2008–2019 (1982)] that knowledge of pressure?temperature auto spectra and cross spectra could be used in a model for sound propagation in a variable duct having acoustic and convected entropy fluctuations. The present exploratory study investigates the measurement of pressure?temperature cross spectra and coherence and temperature cross spectra and coherence at well separated points in a combustion rig. Data obtained near the inlet and the exit of a 6.44?m?long duct attached to a J?47 combustor fueled with hydrogen are presented.

J. H. Miles; C. A. Wasserbauer; E. A. Krejsa

1983-01-01T23:59:59.000Z

317

On the practice of dichotomization of quantitative variables  

E-Print Network (OSTI)

The authors examine the practice of dichotomization of quantitative measures, wherein relationships among variables are examined after 1 or more variables have been converted to dichotomous variables by splitting the sample ...

MacCallum, R. C.; Zhang, S.; Preacher, K. J.; Rucker, D. D.

2002-01-01T23:59:59.000Z

318

Software Enabled Virtually Variable Displacement Pumps -Theoretical and Experimental Studies  

E-Print Network (OSTI)

Software Enabled Virtually Variable Displacement Pumps - Theoretical and Experimental Studies the functional equivalent of a variable displacement pump. This approach combines a fixed displacement pump valve control, without many of the shortcomings of commercially available variable displacement pumps

Li, Perry Y.

319

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

E-Print Network (OSTI)

be used as a variable in biomedical research but mainly toRace’ as a Variable in Biomedical Research A dissertationRace’ as a Variable in Biomedical Research…………. Manifest,

Efstathiou, Sophia

2009-01-01T23:59:59.000Z

320

Anisotropic pressure and hyperons in neutron stars  

E-Print Network (OSTI)

We study the effects of anisotropic pressure on properties of the neutron stars with hyperons inside its core within the framework of extended relativistic mean field. It is found that the main effects of anisotropic pressure on neutron star matter is to increase the stiffness of the equation of state, which compensates for the softening of the EOS due to the hyperons. The maximum mass and redshift predictions of anisotropic neutron star with hyperonic core are quite compatible with the result of recent observational constraints if we use the parameter of anisotropic pressure model $h \\le 0.8$[1] and $\\Lambda \\le -1.15$ [2]. The radius of the corresponding neutron star at $M$=1.4 $M_\\odot$ is more than 13 km, while the effect of anisotropic pressure on the minimum mass of neutron star is insignificant. Furthermore, due to the anisotropic pressure in the neutron star, the maximum mass limit of higher than 2.1 $M_\\odot$ cannot rule out the presence of hyperons in the neutron star core.

A. Sulaksono

2014-12-23T23:59:59.000Z

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.


321

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

322

Stable period 1, 2 and 3 structures of the harmonically excited Rayleigh–Plesset equation applying low ambient pressure  

Science Journals Connector (OSTI)

......HARMONICALLY EXCITED GAS/VAPOUR BUBBLE...As ultrasonic technology is rapidly spreading...novel degassing technology (Yang et al...instance in the development of an `active...1986) Growth of a gas bubble in a viscous...cavitation in hydraulic turbines. Mech. Syst......

F. Hegedus; C. Hos; L. Kullmann

2013-12-01T23:59:59.000Z

323

Pressurized heat treatment of glass ceramic  

DOE Patents (OSTI)

A method of producing a glass-ceramic having a specified thermal expansion value is disclosed. The method includes the step of pressurizing the parent glass material to a predetermined pressure during heat treatment so that the glass-ceramic produced has a specified thermal expansion value. Preferably, the glass-ceramic material is isostatically pressed. A method for forming a strong glass-ceramic to metal seal is also disclosed in which the glass-ceramic is fabricated to have a thermal expansion value equal to that of the metal. The determination of the thermal expansion value of a parent glass material placed in a high-temperature environment is also used to determine the pressure in the environment.

Kramer, D.P.

1984-04-19T23:59:59.000Z

324

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

325

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

326

Piezoelectric Versus Mechanical Spring Pressure Gauge  

Science Journals Connector (OSTI)

That difficulties in the use of various types of pressure gauges warrant meticulous scrutiny in the rendering of an accurate pressure?time curve has advanced each type of gauge for particular work. In powder gas and internal combustion engine gas pressures the spring type and piezoelectric type offer great possibilities with the first a self?contained unit and the latter a charge?collecting device and with the former following the true curve by an admitted time lag and the latter assumed to be responding instantaneously. Sparse comparative records of the two show the case to be more nearly the reverse of what the popular assumption leads one to believe. Fuller data are needed to determine the comparative lagging characteristics of both types.

R. Alden Webster

1939-01-01T23:59:59.000Z

327

Preventing Quantum Hacking in Continuous Variable Quantum Key Distribution  

Science Journals Connector (OSTI)

Security loopholes have been shown for discrete-variable Quantum Key Distribution (QKD). Here, we propose and provide experimental evidence of an attack targeting a continuous-variable...

Jouguet, Paul; Diamanti, Eleni; Kunz-Jacques, Sébastien

328

Impact of Real Field Diesel Quality Variability on Engine Emissions...  

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

Real Field Diesel Quality Variability on Engine Emissions and Fuel Consumption Solutions for Onboard Optimisation Impact of Real Field Diesel Quality Variability on Engine...

329

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

Open Energy Info (EERE)

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

330

Microstructural Response of Variably Hydrated Ca-Rich Montmorillonite...  

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

Microstructural Response of Variably Hydrated Ca-Rich Montmorillonite to Supercritical CO2. Microstructural Response of Variably Hydrated Ca-Rich Montmorillonite to Supercritical...

331

Pitch-variable blazed grating consisting of freestanding silicon beams  

Science Journals Connector (OSTI)

Theoretical analysis is presented for a pitch-variable blazed grating which consists of freestanding silicon beams. The pitch-variable blazed grating is implemented by combining...

Wang, Yongjin; Kanamori, Yoshiaki; Hane, Kazuhiro

2009-01-01T23:59:59.000Z

332

Advanced Variable Speed Air-Source Integrated Heat Pump 2013...  

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

Advanced Variable Speed Air-Source Integrated Heat Pump 2013 Peer Review Advanced Variable Speed Air-Source Integrated Heat Pump 2013 Peer Review Emerging Technologies Project for...

333

Nonmonotone line search methods with variable sample size  

E-Print Network (OSTI)

The nonmonotone line search framework is embedded with a variable sample size ... the line search combines well with the variable sample size scheme as.

2014-02-17T23:59:59.000Z

334

Solutions for Interharmonics in Variable Speed Drives for LNG Plants:.  

E-Print Network (OSTI)

??Variable speed drives can cause components of any frequency known as interharmonics. Large variable speed drives in the order of tens of megawatts can replace… (more)

Verhulst, M.P.A.

2011-01-01T23:59:59.000Z

335

INSTALLATION, COMMISSIONING AND TROUBLE SHOOTING OF VARIABLE FREQUENCY DRIVE.  

E-Print Network (OSTI)

??In this thesis, the installation of variable frequency drive on board a ship is introduced briefly. In this particular study the variable frequency drive was… (more)

Kuituniemi, Santtu

2013-01-01T23:59:59.000Z

336

Control Strategies for Centrifugal Pumps with Variable Flow Rate...  

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

Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements This tip sheet discusses...

337

Variable Renewable Energy: a Regulatory Roadmap (Fact Sheet)...  

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

Variable Renewable Energy: a Regulatory Roadmap Research Highlights There is not a one-size-fits-all approach to the regulation of variable renewable energy (VRE), but...

338

Estimating climatological variability of solar energy production  

Science Journals Connector (OSTI)

Abstract A method is presented for estimating the climatological variability of yearly and monthly photovoltaic power production per 1 kWp of installed power. This quantity is computed for a specified portfolio of sources on the basis of historical data. Its climatological variability is derived from a simulation of 33 years of power production with hourly time step. Underlying meteorological variables are taken from the MERRA reanalysis for the years 1979–2011. Since the MERRA reanalysis is not a traditional data source for photovoltaic power modelling, various comparisons to available and more frequently used data sources are included. The method of estimation has the advantage of wide applicability due to the global coverage of the meteorological data.

Pavel Juruš; Kryštof Eben; Jaroslav Resler; Pavel Kr?; Ivan Kasanický; Emil Pelikán; Marek Brabec; Ji?í Hošek

2013-01-01T23:59:59.000Z

339

Measuring spatial variability in soil characteristics  

DOE Patents (OSTI)

The present invention provides systems and methods for measuring a load force associated with pulling a farm implement through soil that is used to generate a spatially variable map that represents the spatial variability of the physical characteristics of the soil. An instrumented hitch pin configured to measure a load force is provided that measures the load force generated by a farm implement when the farm implement is connected with a tractor and pulled through or across soil. Each time a load force is measured, a global positioning system identifies the location of the measurement. This data is stored and analyzed to generate a spatially variable map of the soil. This map is representative of the physical characteristics of the soil, which are inferred from the magnitude of the load force.

Hoskinson, Reed L. (Rigby, ID); Svoboda, John M. (Idaho Falls, ID); Sawyer, J. Wayne (Hampton, VA); Hess, John R. (Ashton, ID); Hess, J. Richard (Idaho Falls, ID)

2002-01-01T23:59:59.000Z

340

High-pressure cell for neutron diffraction with in situ pressure control at cryogenic temperatures  

SciTech Connect

Pressure generation at cryogenic temperatures presents a problem for a wide array of experimental techniques, particularly neutron studies due to the volume of sample required. We present a novel, compact pressure cell with a large sample volume in which load is generated by a bellow. Using a supply of helium gas up to a pressure of 350 bar, a load of up to 78 kN is generated with leak-free operation. In addition, special fiber ports added to the cryogenic center stick allow for in situ pressure determination using the ruby pressure standard. Mechanical stability was assessed using finite element analysis and the dimensions of the cell have been optimized for use with standard cryogenic equipment. Load testing and on-line experiments using NaCl and BiNiO{sub 3} have been done at the WISH instrument of the ISIS pulsed neutron source to verify performance.

Jacobsen, Matthew K.; Ridley, Christopher J.; Bocian, Artur; Kamenev, Konstantin V., E-mail: k.kamenev@ed.ac.uk [School of Engineering and CSEC, University of Edinburgh, Edinburgh (United Kingdom); Kirichek, Oleg; Manuel, Pascal; Khalyavin, Dmitry [ISIS, Rutherford Appleton Laboratory, Harwell Oxford (United Kingdom)] [ISIS, Rutherford Appleton Laboratory, Harwell Oxford (United Kingdom); Azuma, Masaki [Materials and Structures Laboratory, Tokyo Institute of Technology, Tokyo (Japan)] [Materials and Structures Laboratory, Tokyo Institute of Technology, Tokyo (Japan); Attfield, J. Paul [School of Chemistry and CSEC, University of Edinburgh, Edinburgh (United Kingdom)] [School of Chemistry and CSEC, University of Edinburgh, Edinburgh (United Kingdom)

2014-04-15T23:59:59.000Z

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

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"

342

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

343

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"

344

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

345

On-engine evaluation of emission characteristics of a variable geometry lean-premixed combustor  

SciTech Connect

The design and on-engine testing of a lean-premixed, low-NO{sub x} combustor for a simple-cycle, single-shaft, 250-kW gas turbine engine of a pressure ratio of eight are described. A variable-geometry system composed of butterfly air valves was used to control the combustor air split between combustion and dilution. Fuel was staged to a direct-injection pilot burner, and a lean-premixed main burner was fitted to the combustor liner. The NO{sub x} emissions with natural gas fueling were found to be less than 20 ppm (at 5% O{sub 2}) at and near full-load conditions with combustion efficiencies greater than 99.8%. Emissions data from early high-pressure rig tests of the combustor hardware are also presented.

Yamada, H.; Shimodaira, K.; Hayashi, S. [National Aerospace Lab., Tokyo (Japan). Thermofluid Dynamics Div.

1997-01-01T23:59:59.000Z

346

Multiplexed pressure sensing with elastomer membranes Antony Orth,*a  

E-Print Network (OSTI)

demonstrate a novel optical pressure measurement platform for microfluidics. The pressure sensors operate be used to perform sensitive multiplexed pressure measurements in microfluidic channels. Introduction Pressure is a fundamental quantity of interest in fluid dynamics. Given the recent focus on microfluidic

347

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

348

Studies on performance characteristics of a solar parabolic trough concentrator with a variable area absorber  

Science Journals Connector (OSTI)

The design of a suitable absorber that incorporates an efficient heat transfer augmentation technique is one of the vital parameters that affect the performance of a solar parabolic trough concentrator (PTC). The variable area absorber discussed in this paper provides appreciable augmentation in heat transfer without increasing the pressure drop materially and thus helps in enhancing the performance efficiency of PTC significantly. A computer aided parametric study of this phenomena has been dealt in this paper. The performance of PTC of proposed design has been analysed mathematically and a rigorous simulation model has been developed. The mathematical analysis has been substantiated by elaborate experimental data.

C.M. Narayanan

2014-01-01T23:59:59.000Z

349

Integrating VAV zone requirements with supply fan operation. [Variable Air Volume  

SciTech Connect

The use of communicating direct digital controls (DDC) with distributed intelligence offers new opportunities for energy conservation while maintaining occupant comfort in commercial buildings. Integrating control within a single DDC panel improves performance. Integrating control by communications between multiple controllers can further enhance system operation. One example is a DDC static pressure reset strategy for supply fan operation in variable air volume (VAV) supply air distribution systems. This strategy integrates the requirements of the VAV terminal units serving the building zones to minimize fan energy use. This article describes terminal unit operation, supply fan control, concurrent polling, operational data and power savings.

Warren, M.L. (ASI Controls, San Ramon, CA (United States)); Norford, L.K. (Massachusetts Inst. of Tech., Cambridge (United States))

1993-04-01T23:59:59.000Z

350

Fracturing pressures and near-well fracture geometry of arbitrarily oriented and horizontal wells  

SciTech Connect

The hydraulic fracturing of arbitrarily oriented and horizontal wells is made challenging by the far more complicated near-well fracture geometry compared to that of conventional vertical wells. This geometry is important both for hydraulic fracture propagation and the subsequent post-treatment well performance. Fracture tortuosity of arbitrarily oriented and horizontal wells is likely to cause large initiation pressures and reduction in the fracture widths. This paper presents a comprehensive study of the effects of important variables, including the principal stresses, wellbore orientation, and perforation configuration on fracture geometry. Initiation pressures, the contact between arbitrarily oriented wells and the fracture plane, and the near-well fracture geometry are determined and discussed. This study also shows that because of the near-well stress concentration the fracture width at the wellbore is always smaller than the maximum fracture width. This can have important consequences during hydraulic fracturing.

Chen, Z.; Economides, M.J.

1995-12-31T23:59:59.000Z

351

Velocity of Sound Measurements in High?Pressure, High?Temperature Steam  

Science Journals Connector (OSTI)

Experimental information concerning the acoustic velocity in steam as a function of pressure and temperature is quite limited. Yet it is of particular interest to steam turbine designers who are now planning units as large as 400 000 kw operating at 4500 lb/sq in. and 1200°F so as to increase thermal efficiencies of such units. Apparatus is now in operation for measuring the acoustic velocity up to 2000 lb/sq in. and 750°F using a variable path acoustic interferometer.Measurements are taken at 200?lb/sq in. intervals along a given isotherm using a sound frequency of 750 kc. A special experimental high?pressure boiler is used to generate the steam at the desired pressure and the stem is then increased in temperature by means of a stainless steel superheater before entering the interferometer. The interferometer also of stainless steel is enclosed by an insulated steel vessel maintained at a given constant temperature by another separate steam system. Future work is now being considered up to 6000?lb/sq in. steam pressure based upon results of present experiments.

James Woodburn

1960-01-01T23:59:59.000Z

352

Pressure-flow reducer for aerosol focusing devices  

DOE Patents (OSTI)

A pressure-flow reducer, and an aerosol focusing system incorporating such a pressure-flow reducer, for performing high-flow, atmosphere-pressure sampling while delivering a tightly focused particle beam in vacuum via an aerodynamic focusing lens stack. The pressure-flow reducer has an inlet nozzle for adjusting the sampling flow rate, a pressure-flow reduction region with a skimmer and pumping ports for reducing the pressure and flow to enable interfacing with low pressure, low flow aerosol focusing devices, and a relaxation chamber for slowing or stopping aerosol particles. In this manner, the pressure-flow reducer decouples pressure from flow, and enables aerosol sampling at atmospheric pressure and at rates greater than 1 liter per minute.

Gard, Eric (San Francisco, CA); Riot, Vincent (Oakland, CA); Coffee, Keith (Diablo Grande, CA); Woods, Bruce (Livermore, CA); Tobias, Herbert (Kensington, CA); Birch, Jim (Albany, CA); Weisgraber, Todd (Brentwood, CA)

2008-04-22T23:59:59.000Z

353

PRESSURE TRANSIENT ANALYSIS FOR COMPOSITE SYSTEMS  

E-Print Network (OSTI)

SGP-TR-117 PRESSURE TRANSIENT ANALYSIS FOR COMPOSITE SYSTEMS Ani1 Kumar Ambastha October 1988 my graduate studies. #12;f #12;ABSTRACT A composite reservoir model is used to analyze well. A composite reservoir is made up of two or more regions. Each region has its own rock and fluid properties

Stanford University

354

Kinetics of Non-Thermal Atmospheric Pressure  

E-Print Network (OSTI)

Kinetics of Non-Thermal Atmospheric Pressure Plasmas Alexander Fridman · Microdischarge Interaction and Structuring in Dielectric Barrier Discharges · Kinetics of Blood Coagulation in Plasma · Surface Wound wire Area of DBD plasma region: ~104cm2 #12;7 Microdischarge Patterning (2D) R22 R23 R24 R26 R27 R28

Kaganovich, Igor

355

PRESSURIZED EQUIPMENT AND SYSTEMS Table Of Contents  

E-Print Network (OSTI)

with inspection doors (such as oil-filled (governor) pressure tanks), hydrostatic tests need only be given, such as air, are prohibited, except for: (1) testing of bulk petroleum, oil, and lubricant (POL) storage tanks Compressed Air and Gas Systems.............................. 20-5 20.C Boilers and Systems

US Army Corps of Engineers

356

Column Design in High Pressure Liquid Chromatography  

Science Journals Connector (OSTI)

......consideration, and the high inlet pressure is the price to be paid for the short analysis time...silicious support impregnated with paraffin oil in reversed phase chromatography. As op...in the above described manner following heating of the product at 450 C. With relatively......

Csaba Horvath; S. R. Lipsky

1969-02-01T23:59:59.000Z

357

Reconstruction of Pressure Profile Evolution during  

E-Print Network (OSTI)

. Boxer, J. Ellsworth, D. Garnier, J. Kesner Plasma Science & Fusion Center Massachusetts Institue. 77 Massachusetts Avenue, NW16, Cambridge, MA 02139 phone: 617-253-8100, info@psfc.mit.edu APS-Parker-Sckopke Relation (Burton, McPherron, Russell, JGR, 1975) Solar Wind Pressure Solar Wind Convection Field 5 MA Dst 1

358

Reconstruction of Pressure Profile Evolution during  

E-Print Network (OSTI)

. Boxer, J. Ellsworth, D. Garnier, J. Kesner Plasma Science & Fusion Center Massachusetts Institue. 77 Massachusetts Avenue, NW16, Cambridge, MA 02139 phone: 617-253-8100, info@psfc.mit.edu ICC-Parker-Sckopke Relation (Burton, McPherron, Russell, JGR, 1975) Solar Wind Pressure Solar Wind Convection Field 5 MA Dst 1

359

Column Design in High Pressure Liquid Chromatography  

Science Journals Connector (OSTI)

......School of Medicine, New Haven, Connecticut Presented at the Fit th International...high inlet pressure is the price to be paid for the short analysis...support impregnated with paraffin oil in reversed phase chromatography...described manner following heating of the product at 450 C. With......

Csaba Horvath; S. R. Lipsky

1969-02-01T23:59:59.000Z

360

Pressure wave charged repetitively pulsed gas laser  

DOE Patents (OSTI)

A repetitively pulsed gas laser in which a system of mechanical shutters bracketing the laser cavity manipulate pressure waves resulting from residual energy in the cavity gas following a lasing event so as to draw fresh gas into the cavity and effectively pump spent gas in a dynamic closed loop.

Kulkarny, Vijay A. (Redondo Beach, CA)

1982-01-01T23:59:59.000Z

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.


361

Geological Aspects of High-Pressure Research  

Science Journals Connector (OSTI)

...garnet-pyroxene assemblage typical of eclogites by heating it for an hour at 1200 C at a pressure...eclogite at the M discontinuity. The geothermal gradient would have to have curved so...kyanite-sillimanite transition three times. The geothermal gradient probably has a slope not far...

F. R. Boyd

1964-07-03T23:59:59.000Z

362

Star wars: US pressure on Japan  

Science Journals Connector (OSTI)

... US Strategic Defense Initiative ("star wars") seems to have found a fan in Japan's Prime Minister Yasuhiro Nakasone, who has been extolling its virtues in recent Diet ... after his meeting with President Ronald Reagan in Los Angeles earlier this year. Pressure for Japan to make its support official is being kept up by a series of visits from ...

David Swinbanks

1985-04-25T23:59:59.000Z

363

An Exploratory Study of Variability in Safety  

E-Print Network (OSTI)

An Exploratory Study of Variability in Safety Culture among Clinician types and Patient Care of the current study was to (a) examine how different types of care providers viewed the safety culture of their unit, and (b) examine the relationship between hospital safety culture and patient satisfaction

von der Heydt, RĂĽdiger

364

SYNTHESIS: MODELING VARIABILITY AND CONSTRAINTS Rolf Carlson  

E-Print Network (OSTI)

SYNTHESIS: MODELING VARIABILITY AND CONSTRAINTS Rolf Carlson This is a modified version. Abstract This paper discusses some important topics in current speech synthesis research. Modeling of speaker characteristics and emotions are used as a examples of new trends in the speech synthesis field

Carlson, Rolf

365

Galactic Variable Sky with EGRET and GLAST  

SciTech Connect

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

366

TimeVariable Photo-Evaporation of  

E-Print Network (OSTI)

TimeVariable Photo-Evaporation of Protoplanetary Disks Henry Throop (SwRI) John Bally (U. Colorado) #12;Takeaway: Photo-evaporation alters the disk structure in essentially unpredictable ways, because for disks formed at the same time in the same cluster. #12;30 Doradus: 100+ O/B stars Photo

Throop, Henry

367

Heart Rate Variability Malvin Carl Teich  

E-Print Network (OSTI)

Heart Rate Variability Malvin Carl Teich Boston University and Columbia University http, Grasmere, UK, 2005 #12;CONGESTIVE HEART FAILURE INABILITY OF HEART TO INCREASE CARDIAC OUTPUT IN PROPORTION of breath Swelling in legs General fatigue and weakness Clinical diagnostics: Ascultate heart Carotid pulse

Teich, Malvin C.

368

The QSO variability-luminosity-redshift relation  

Science Journals Connector (OSTI)

......to test Poissonian (or 'Christmas-tree') models for QSO variability...mean B-band luminosity in the light curve and a(LB) is its standard...comparison of the UV and optical light curves of NGC 4151 and 5548...spanning 16 yr. The rest-frame light curves are between 3.2 and......

Roberto Cid Fernandes; Jr; Itziar Aretxaga; Roberto Terlevich

1996-10-11T23:59:59.000Z

369

The Sun is an active, variable,  

E-Print Network (OSTI)

The Sun is an active, variable, magnetic star with oscillations on its surface and deep within its the physical processes of the Sun-Earth connection. Visit Us on the Web: Solar Terrestrial Probes Program: http://stp.gsfc.nasa.gov For More Information, See: Sun-Earth Connection: http://sec.gsfc.nasa.gov Living With a Star: http

Christian, Eric

370

Chapter 18: Variable Frequency Drive Evaluation Protocol  

SciTech Connect

An adjustable-speed drive (ASD) includes all devices that vary the speed of a rotating load, including those that vary the motor speed and linkage devices that allow constant motor speed while varying the load speed. The Variable Frequency Drive Evaluation Protocol presented here addresses evaluation issues for variable-frequency drives (VFDs) installed on commercial and industrial motor-driven centrifugal fans and pumps for which torque varies with speed. Constant torque load applications, such as those for positive displacement pumps, are not covered by this protocol. Other ASD devices, such as magnetic drive, eddy current drives, variable belt sheave drives, or direct current motor variable voltage drives, are also not addressed. The VFD is by far the most common type of ASD hardware. With VFD speed control on a centrifugal fan or pump motor, energy use follows the affinity laws, which state that the motor electricity demand is a cubic relationship to speed under ideal conditions. Therefore, if the motor runs at 75% speed, the motor demand will ideally be reduced to 42% of full load power; however, with other losses it is about 49% of full load power.

Romberger, J.

2014-11-01T23:59:59.000Z

371

Variable Light-Cone Theory of Gravity  

E-Print Network (OSTI)

We show how to reformulate Variable Speed of Light Theories (VSLT) in a covariant fashion as Variable Light-Cone Theories (VLCT) by introducing two vierbein bundles each associated with a distinct metric. The basic gravitational action relates to one bundle while matter propagates relative to the other in a conventional way. The variability of the speed of light is represented by the variability of the matter light-cone relative to the gravitational light-cone. The two bundles are related locally by an element M, of SL(4,R). The dynamics of the field M is that of a SL(4,R)-sigma model gauged with respect to local (orthochronous) Lorentz transformations on each of the bundles. Only the ``massless'' version of the model with a single new coupling, F, that has the same dimensions as Newton's constant $G_N$, is considered in this paper. When F vanishes the theory reduces to standard General Relativity. We verify that the modified Bianchi identities of the model are consistent with the standard conservation law for the matter energy-momentum tensor in its own background metric. The implications of the model for some simple applications are examined, the Newtonian limit, the flat FRW universe and the spherically symmetric static solution.

I. T. Drummond

1999-08-20T23:59:59.000Z

372

Variability viewpoint to describe reference architectures  

Science Journals Connector (OSTI)

Reference architectures have emerged as a special type of software architecture that achieves well-recognized understanding of specific domains. Their purpose is therefore to be a guidance for the development, standardization, and evolution of systems ... Keywords: architecture description, reference architecture, variability

Milena Guessi; Flavio Oquendo; Elisa Yumi Nakagawa

2014-04-01T23:59:59.000Z

373

Accounting for water-column variability in shallow-water waveguide characterizations based on modal eigenvalues  

SciTech Connect

The influence of water-column variability on the characterization of shallow-water waveguides using modal eigenvalue information is considered. This work is based on the relationship between the acoustic pressure field in shallow water and the depth-dependent Green's function through the Hankel transform. In many practical situations, the Hankel transform can be approximated by a Fourier transform, in which case the Green's function is approximated by a horizontal wave number spectrum with discrete peaks corresponding with individual modal eigenvalues. In turn, the wave number data can be used in inverse algorithms to determine geoacoustic properties of the waveguide. Wave number spectra are estimated from measurements of a point-source acoustic field on a horizontal aperture array in the water column. For range-dependent waveguides, techniques analogous to using a short-time Fourier transform are employed to estimate range-dependent wave number spectra. In this work, water-column variability due to linear internal waves and mesoscale features are considered. It will be shown that these two types of variability impact the estimation of range-dependent modal eigenvalues in different ways. Approaches for accounting for these different types of variability will be discussed as they apply to waveguide characterization.

Becker, Kyle M. [Pennsylvania State University, Applied Research Laboratory, P.O. Box 30, State College, PA 16804-0030 (United States); Ballard, Megan S. [Applied Research Laboratories, University of Texas at Austin, Austin, TX 78713-8029 (United States)

2010-09-06T23:59:59.000Z

374

Theory of the transient pressure response of fluid?filled porous media  

Science Journals Connector (OSTI)

A theory is developed to describe the transient pressure response of rigid isotropic and uniform porous media including the higher?order effects of viscous dissipation and thermal conduction. A transfer function which is transcendental in the Laplace time?image variable is obtained for the system. For the case of sinusoidal excitation the results reduce to those given earlier by Smith and Greenkorn [J. Acoust. Soc. Am. 52 247–253 (1972)]. Rational approximations are developed for the regime limiting cases of viscosity (long transient times or low frequencies) and inertia (short transient times or high frequencies) and are used to derive the system step and impulse responses.

Peter G. Smith; Robert A. Greenkorn; Ronald G. Barile

1974-01-01T23:59:59.000Z

375

The microstructure and hardness of molybdenum powders consolidated by plasma pressure compaction  

Science Journals Connector (OSTI)

Bulk molybdenum samples were prepared by consolidating molybdenum powders using the technique of plasma pressure compaction (P2C). The specimens were obtained by consolidating the powder particles under conditions of pulse and no-pulse and at two different temperatures. Results reveal that pulsing of the powders prior to consolidation had little influence on microhardness when compared to the samples that were obtained by consolidating the powder particles under no-pulse. Both nanohardness and microhardness measurements revealed a marginal decrease with an increase in temperature of compaction. The influence of processing variables on microstructural development and hardness is presented and discussed.

T.S Srivatsan; B.G Ravi; A.S Naruka; L Riester; M Petraroli; T.S Sudarshan

2001-01-01T23:59:59.000Z

376

Advanced Diagnostics for High Pressure Spray Combustion.  

SciTech Connect

The development of accurate predictive engine simulations requires experimental data to both inform and validate the models, but very limited information is presently available about the chemical structure of high pressure spray flames under engine- relevant conditions. Probing such flames for chemical information using non- intrusive optical methods or intrusive sampling techniques, however, is challenging because of the physical and optical harshness of the environment. This work details two new diagnostics that have been developed and deployed to obtain quantitative species concentrations and soot volume fractions from a high-pressure combusting spray. A high-speed, high-pressure sampling system was developed to extract gaseous species (including soot precursor species) from within the flame for offline analysis by time-of-flight mass spectrometry. A high-speed multi-wavelength optical extinction diagnostic was also developed to quantify transient and quasi-steady soot processes. High-pressure sampling and offline characterization of gas-phase species formed following the pre-burn event was accomplished as well as characterization of gas-phase species present in the lift-off region of a high-pressure n-dodecane spray flame. For the initial samples discussed in this work several species were identified, including polycyclic aromatic hydrocarbons (PAH); however, quantitative mole fractions were not determined. Nevertheless, the diagnostic developed here does have this capability. Quantitative, time-resolved measurements of soot extinction were also accomplished and the novel use of multiple incident wavelengths proved valuable toward characterizing changes in soot optical properties within different regions of the spray flame.

Skeen, Scott A.; Manin, Julien Luc; Pickett, Lyle M.

2014-06-01T23:59:59.000Z

377

Correlated spectral variability in brown dwarfs  

E-Print Network (OSTI)

Models of brown dwarf atmospheres suggest they exhibit complex physical behaviour. Observations have shown that they are indeed dynamic, displaying small photometric variations over timescales of hours. Here I report results of infrared (0.95-1.64 micron) spectrophotometric monitoring of four field L and T dwarfs spanning timescales of 0.1-5.5 hrs, the goal being to learn more about the physical nature of this variability. Spectra are analysed differentially with respect to a simultaneously observed reference source in order to remove Earth-atmospheric variations. The variability amplitude detected is typically 2-10%, depending on the source and wavelength. I analyse the data for correlated variations between spectral indices. This approach is more robust than single band or chisq analyses, because it does not assume an amplitude for the (often uncertain) noise level (although the significance test still assumes a shape for the noise power spectrum). Three of the four targets show significant evidence for correlated variability. Some of this can be associated with specific features including Fe, FeH, VO and KI, and there is good evidence for intrinsic variability in water and possibly also methan. Yet some of this variability covers a broader spectral range which would be consistent with dust opacity variations. The underlying common cause is plausibly localized temperature or composition fluctuations caused by convection. Looking at the high signal-to-noise ratio stacked spectra we see many previously identified spectral features of L and T dwarfs, such as KI, NaI, FeH, water and methane. In particular we may have detected methane absorption at 1.3-1.4 micron in the L5 dwarf SDSS 0539-0059.

C. A. L. Bailer-Jones

2007-11-28T23:59:59.000Z

378

INVESTIGATION OF BUBBLE DYNAMICS AND HEATING DURING FOCUSED ULTRASOUND INSONATION IN TISSUE-MIMICKING MATERIALS.  

E-Print Network (OSTI)

??The deposition of ultrasonic energy in tissue can cause tissue damage due to local heating. For pressures above a critical threshold, cavitation will occur in… (more)

Yang, Xinmai

2010-01-01T23:59:59.000Z

379

Flash High-Pressure Condensate to Regenerate Low-Pressure Steam  

SciTech Connect

This revised ITP tip sheet on regenerating low-pressure steam provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

Not Available

2006-01-01T23:59:59.000Z

380

Pressure Transient Analysis of Bottomhole Pressure and Rate Measurements Using System Identification  

E-Print Network (OSTI)

is a zero rate obtained by a quick-closing down hole valve during "drillstem testing". More inaccurate "zero storage coefficient"). In conventional PTA, the step response in the bottom hole pressure resulting from

Van den Hof, Paul

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

The VISTA Variables in the Via Lactea survey: A first glance on stellar variability  

E-Print Network (OSTI)

VISTA Variables in the Via Lactea (VVV) is an ESO public near-infrared variability survey of the Galactic bulge and an adjacent area of the southern mid-plane. It will produce a deep atlas in the ZYJHKs filters, and a Ks-band time-series database of ~10^9 point sources, among which >~10^6 are expected to be variable. One of VVV's immediate scientific goals is to provide accurate light curves of primary distance indicators, such as RR Lyrae stars, and utilize these data to produce a 3-D map of the surveyed area and, ultimately, trace the structure of the inner Galaxy. We give, based on the first ~1.5 years of the 5-yr-long survey, an early assessment on the basic properties and the overall quality of the VVV photometric time-series, and use these data to put an estimate of the fraction of variable stellar sources.

Dekany, I; Minniti, D

2011-01-01T23:59:59.000Z

382

Experimental and theoretical study of pressure effects on hydrogen isotope fractionation in the system brucite-water at elevated temperatures  

Science Journals Connector (OSTI)

A detailed, systematic experimental and theoretical study was conducted to investigate the effect of pressure on equilibrium D/H fractionation between brucite (Mg(OH)2) and water at temperatures from 200 to 600°C and pressures up to 800 MPa. A fine-grained brucite was isotopically exchanged with excess amounts of water, and equilibrium D/H fractionation factors were calculated by means of the partial isotope exchange method. Our experiments unambiguously demonstrated that the D/H fractionation factor between brucite and water increased by 4.4 to 12.4‰ with increasing pressure to 300 or 800 \\{MPa\\} at all the temperatures investigated. The observed increases are linear with the density of water under experimental conditions. We calculated the pressure effects on the reduced partition function ratios (?-factor) of brucite (300–800 K and P ? 800 MPa) and water (400–600°C and P ? 100 MPa), employing a statistical-mechanical method similar to that developed by Kieffer (1982) and a simple thermodynamic method based on the molar volumes of normal and heavy waters, respectively. Our theoretical calculations showed that the reduced partition function ratio of brucite increases linearly with pressure at a given temperature (as much as 12.6‰ at 300 K and 800 MPa). The magnitude of the pressure effects rapidly decreases with increasing temperature. On the other hand, the ?-factor of water decreases 4 to 5‰ with increasing pressure to 100 \\{MPa\\} at 400 to 600°C. Overall D/H isotope pressure effects combined from the separate calculations on brucite and water are in excellent agreement with the experimental results under the same temperature-pressure range. Our calculations also suggest that under the current experimental conditions, the magnitude of the isotope pressure effects is much larger on water than brucite. Thus, the observed pressure effects on D/H fractionation are common to other systems involving water. It is very likely that under some geologic conditions, pressure is an important variable in controlling D/H partitioning.

Juske Horita; David R. Cole; Veniamin B. Polyakov; Thomas Driesner

2002-01-01T23:59:59.000Z

383

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 â—Ź 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.

384

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

385

Correlated spectral variability in brown dwarfs  

E-Print Network (OSTI)

Models of brown dwarf atmospheres suggest they exhibit complex physical behaviour. Observations have shown that they are indeed dynamic, displaying small photometric variations over timescales of hours. Here I report results of infrared (0.95-1.64 micron) spectrophotometric monitoring of four field L and T dwarfs spanning timescales of 0.1-5.5 hrs, the goal being to learn more about the physical nature of this variability. Spectra are analysed differentially with respect to a simultaneously observed reference source in order to remove Earth-atmospheric variations. The variability amplitude detected is typically 2-10%, depending on the source and wavelength. I analyse the data for correlated variations between spectral indices. This approach is more robust than single band or chisq analyses, because it does not assume an amplitude for the (often uncertain) noise level (although the significance test still assumes a shape for the noise power spectrum). Three of the four targets show significant evidence for cor...

Bailer-Jones, C A L

2007-01-01T23:59:59.000Z

386

X-ray variability in M87  

E-Print Network (OSTI)

We present the evidence for X-ray variability from the core and from knot A in the M87 jet based on data from two observations with the Einstein Observatory High Resolution Imager (HRI) and three observations with the ROSAT HRI. The core intensity showed a 16% increase in 17 months ('79-'80); a 12% increase in the 3 years '92 to '95; and a 17% drop in the last half of 1995. The intensity of knot A appears to have decreased by 16% between 92Jun and 95Dec. Although the core variability is consistent with general expectations for AGN nuclei, the changes in knot A provide constraints on the x-ray emission process and geometry. Thus we predict that the x-ray morphology of knot A will differ significantly from the radio and optical structure.

D. E. Harris; J. A. Biretta; W. Junor

1996-12-05T23:59:59.000Z

387

Variable aperture collimator for high energy radiation  

DOE Patents (OSTI)

An apparatus is disclosed providing a variable aperture energy beam collimator. A plurality of beam opaque blocks are in sliding interface edge contact to form a variable aperture. The blocks may be offset at the apex angle to provide a non-equilateral aperture. A plurality of collimator block assemblies may be employed for providing a channel defining a collimated beam. Adjacent assemblies are inverted front-to-back with respect to one another for preventing noncollimated energy from emerging from the apparatus. An adjustment mechanism comprises a cable attached to at least one block and a hand wheel mechanism for operating the cable. The blocks are supported by guide rods engaging slide brackets on the blocks. The guide rods are pivotally connected at each end to intermediate actuators supported on rotatable shafts to change the shape of the aperture. A divergent collimated beam may be obtained by adjusting the apertures of adjacent stages to be unequal.

Hill, Ronald A. (Albuquerque, NM)

1984-05-22T23:59:59.000Z

388

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

389

Teleportation-Based Continuous Variable Quantum Cryptography  

E-Print Network (OSTI)

We show a continuous variable (CV) quantum key distribution (QKD) scheme based on the CV quantum teleportation of coherent states that yields a raw secret key made up of discrete variables for both Alice and Bob. This protocol preserves the efficient detection schemes of current CV technology (no single-photon detection techniques) and, at the same time, has efficient error correction and privacy amplification schemes due to its binary discrete key. In particular, it is secure for any value of the transmission efficiency of the optical line used by Alice to share entangled two-mode squeezed states with Bob (no 3 dB or 50% loss limitation characteristic of beam splitting attacks). The present CVQKD protocol works deterministically (no postselection needed) with efficient direct reconciliation techniques (no reverse reconciliation) in order to generate a secure key, even at the surprisingly 100% loss case.

F. S. Luiz; Gustavo Rigolin

2014-08-21T23:59:59.000Z

390

Magnetic Switching under Pressure | Advanced Photon Source  

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

Revealing the Secrets of Chemical Bath Deposition Revealing the Secrets of Chemical Bath Deposition DNA Repair Protein Caught in the Act of Molecular Theft Velcro for Nanoparticles A Molecular Fossil Ultrafast Imaging of Electron Waves in Graphene Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed Magnetic Switching under Pressure DECEMBER 2, 2010 Bookmark and Share A schematic representation of the pressure-induced magnetic switching effect. The colored images highlight the direction of the magnetic orbital (grey plane) for the copper centers (green balls: copper, blue: nitrogen, red: oxygen/water, yellow: fluoride). A material's properties are a critical factor in the way that material

391

BOP Pressure Summary 28 May 2010  

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

Pressures (psi) +/- 50 psi" Pressures (psi) +/- 50 psi" ,,,,,,,"Pre Kill","Post Kill","Post Junk","Post Junk shot 2" ,,,,,,,2250,2250,2250,2250 ,,,,,,"Delta",310,250,229 ,,,,,,,2560,2500,2479 ,,,,,,"Delta",60,120,108,493 ,,,,,,,2620,2620,2587,2743 ,,,,,,"Delta",620,510,794,410 ,,,,,,,3240,3130,3381,3153 ,,,,,,"Delta",430,150,284,242 ,,26.51,,,,,3670,3280,3665,3395 ,,,,,,"Delta",730,40,32,101 ,,,,,,"BOP Pres",4400,3320,3697,3496 ,,,,,,"(corrected)","(Test Ram closed)","(Test Ram open)","(Test Ram open)","(Test Ram open)" "Top of Wellhead:",,"5053 ft" ,"BP MACONDO" ,"TOP KILL PROCEDURE - MC252 #1"

392

Pressure Change Measurement Leak Testing Errors  

SciTech Connect

A pressure change test is a common leak testing method used in construction and Non-Destructive Examination (NDE). The test is known as being a fast, simple, and easy to apply evaluation method. While this method may be fairly quick to conduct and require simple instrumentation, the engineering behind this type of test is more complex than is apparent on the surface. This paper intends to discuss some of the more common errors made during the application of a pressure change test and give the test engineer insight into how to correctly compensate for these factors. The principals discussed here apply to ideal gases such as air or other monoatomic or diatomic gasses; however these same principals can be applied to polyatomic gasses or liquid flow rate with altered formula specific to those types of tests using the same methodology.

Pryor, Jeff M [ORNL] [ORNL; Walker, William C [ORNL] [ORNL

2014-01-01T23:59:59.000Z

393

Casing design for trapped annular pressure buildup  

SciTech Connect

Conventional single-string analysis for casing design with annular-fluid expansion can underpredict or overpredict pressures between strings because multistring effects are neglected. Multiple-string systems with multiple sealed annuli behave as composite interactive systems. This paper presents a constitutive-based multistring analysis method for composite string effects and complex fluid behavior. The composite stiffness of cemented casings is determined from elastic stress/strain relationships, and the nonlinear fluid behavior is modeled by direct use of fluid PVT relations in the formulation and solution. The method is incorporated in a computer model linking comprehensive stress calculations to accurate temperature and pressure predictions. Sensitivity studies of the system response to various key parameters and operating conditions are presented, and comparisons are made with single-string analyses to demonstrate the strong interaction between casing strings.

Halal, A.S.; Mitchell, R.F. (Enertech Engineering Research Co., Houston, TX (United States))

1994-06-01T23:59:59.000Z

394

Boron determinations in pressure vessel steels  

SciTech Connect

Several studies have suggested that low-energy neutrons contribute to reactor pressure vessel (PV) embrittlement through interactions with boron impurities in the steel. Until now, the available information on boron contents in pressure vessel steels has been based on nominal concentrations or estimates provided by the materials manufacturers. To help resolve the question of boron contribution to PV steel embrittlement, samples of 38 different PV steels were analyzed by high-sensitivity gas mass spectrometry for their helium and boron contents. The boron contents were determined by measuring the increase in helium content in each material as a result of additional thermal neutron exposure. The results of these analyses showed natural boron contents that ranged from 0.23 to 5.11 wt. ppm in the various alloys.

Oliver, B.M. [Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.; McElroy, W.N. [Consultants and Technology Services, Richland, WA (United States); Kellogg, L.S. [Battelle-Pacific Northwest Lab., Richland, WA (United States); Farrar, H. IV

1994-12-31T23:59:59.000Z

395

Detecting solar chameleons through radiation pressure  

E-Print Network (OSTI)

Light scalar fields can drive the accelerated expansion of the universe. Hence, they are obvious dark energy candidates. To make such models compatible with tests of General Relativity in the solar system and "fifth force" searches on Earth, one needs to screen them. One possibility is the so-called "chameleon" mechanism, which renders an effective mass depending on the local matter density. If chameleon particles exist, they can be produced in the sun and detected on earth exploiting the equivalent of a radiation pressure. Since their effective mass scales with the local matter density, chameleons can be reflected by a dense medium if their effective mass becomes greater than their total energy. Thus, under appropriate conditions, a flux of solar chameleons may be sensed by detecting the total instantaneous momentum transferred to a suitable opto-mechanical force/pressure sensor. We calculate the solar chameleon spectrum and the reach in the chameleon parameter space of an experiment using the preliminary re...

Baum, S; Hoffmann, D H H; Karuza, M; Semertzidis, Y K; Upadhye, A; Zioutas, K

2014-01-01T23:59:59.000Z

396

Buoyancy-generated variable-density turbulence  

SciTech Connect

Because of the importance of turbulence mixing in many applications, a number of turbulence mixing models have been proposed for variable- density flows. These engineering models (one- point statistical models) typically include the transport of the turbulent kinetic energy and the turbulent energy dissipation rate (i.e., k - {epsilon} models). The model presented by Besnard, Harlow, Rauenzahn and Zemach (1992) (herein referred to as BHRZ) is a one-point model intended to describe variable-density turbulent flows. Transport equations for the Reynolds stress tensor, R{sub ij}, and the turbulent energy dissipation rate, the density-velocity correlation, a{sub i}, and the density-specific volume correlation, b are derived. This model employs- techniques and concepts from incompressible, constant- density turbulence modeling and incorporates ideas from two-phase flow models. Clark and Spitz (1994) present a two-point model for variable-density turbulence. Their derivation is based on transport equations that, are based 0481 on two-point- generalizations of R{sub ij}, a{sub ij}, and b. These equations are Fourier transformed with respect to the separation distance between the two points. Transport equations are derived for R{sub ij}, a{sub i}, b. As in the one-point model, this model contains many ad-hoc assumptions and unknown model coefficients that must be determined by comparison with experimental and numerical data. However, the two-point formalism requires fewer equilibrium assumptions then does a single-point model. Our primary concern in this paper lies in the nonlinear processes of turbulence and the influence of large density variations (not within the Boussinesq limit) on these processes. To. isolate the effects of variable-density on the turbulence we restrict our flow to be incompressible, statistically homogeneous buoyancy-generated. turbulence. To our knowledge there have not been any simulations reported for this problem.

Sandoval, D.L.; Clark, T.T.; Riley, J.J.

1996-07-01T23:59:59.000Z

397

The dynamics of variable-density turbulence  

SciTech Connect

The dynamics of variable-density turbulent fluids are studied by direct numerical simulation. The flow is incompressible so that acoustic waves are decoupled from the problem, and implying that density is not a thermodynamic variable. Changes in density occur due to molecular mixing. The velocity field is, in general, divergent. A pseudo-spectral numerical technique is used to solve the equations of motion. Three-dimensional simulations are performed using a grid size of 128{sup 3} grid points. Two types of problems are studied: (1) the decay of isotropic, variable-density turbulence, and (2) buoyancy-generated turbulence in a fluid with large density fluctuations (such that the Boussinesq approximation is not valid). In the case of isotropic, variable-density turbulence, the overall statistical decay behavior, for the cases studied, is relatively unaffected by the presence of density variations when the initial density and velocity fields are statistically independent. The results for this case are in quantitative agreement with previous numerical and laboratory results. In this case, the initial density field has a bimodal probability density function (pdf) which evolves in time towards a Gaussian distribution. The pdf of the density field is symmetric about its mean value throughout its evolution. If the initial velocity and density fields are statistically dependent, however, the decay process is significantly affected by the density fluctuations. For this case, the pdf of the density becomes asymmetric about its mean value during the early stages of its evolution. It is argued that these asymmetries in the pdf of the density field are due to different entrainment rates, into the mixing region, that favor the high speed fluid.

Sandoval, D.L.

1995-11-01T23:59:59.000Z

398

Multivector Functions of a Multivector Variable  

E-Print Network (OSTI)

In this paper we develop with considerable details a theory of multivector functions of a $p$-vector variable. The concepts of limit, continuity and differentiability are rigorously studied. Several important types of derivatives for these multivector functions are introduced, as e.g., the $A$% -directional derivative (where $A$ is a $p$-vector) and the generalized concepts of curl, divergence and gradient. The derivation rules for different types of products of multivector functions and for compositon of multivector functions are proved.

A. M. Moya; V. V. Fernández; W. A. Rodrigues Jr

2002-12-18T23:59:59.000Z

399

Hidden Variables and Quantum Statistics Nature  

E-Print Network (OSTI)

It is shown that the nature of quantum statistics can be clarified by assuming the existence of a background of random gravitational fields and waves, distributed isotropically in the space. This background is responsible for correlating phases of oscillations of identical microobjects. If such a background of random gravitational fields and waves is considered as hidden variables then taking it into account leads to the Bell-type inequalities that are fairly consistent with the experimental data.

T. F. Kamalov

2007-03-14T23:59:59.000Z

400

Variable Row Spacing of Irrigated Cotton.  

E-Print Network (OSTI)

B-1 lr August 19; aria ble Row Spacing of Irrigated Cotton I as A&M University Texas Agricultural Experiment Station . H. 0. Kunkel, Acting Director, College Station, Texa! Summary Six years' research in the Trans-Pecos area with "variable... row spacing" (VRS), new irrigated cotton row-spacing patterns, is reported. The new system consists of alternate close and ~ricle spaced rows, with narrow irrigation furrows between the close row spacings only. The wide spac- ings serve as dry...

Longenecker, D. E.; Thaxton, E. L. Jr.; Hefner, J. J.; Lyerly, P. J.

1970-01-01T23:59:59.000Z

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.


401

Teleportation using continuous variable quantum cloning machine  

E-Print Network (OSTI)

We show that an unknown quantum state in phase space can be teleported via three-mode entanglement generated by continuous variable quantum cloning machine (transformation). Further, proceeding with our teleportation protocol we are able to improve the fidelity of teleportation obtained by Loock et.al. [Phys.Rev.Lett. 84, 3482(2000)]. Also we study here the entanglement between the two output copies from cloning machine.

Satyabrata Adhikari

2008-02-15T23:59:59.000Z

402

Is Salinity Variability a Benthic Disturbance?  

E-Print Network (OSTI)

include: salinity, pH, dissolved oxygen, temperature, conductivity, oxidation-reduction potential, and depth (Monatgna and Kalke 1992, 1995). Measurements were collected both at depth (0.1 m above bay bottom) and at the surface using a sonde... IS SALINITY VARIABILITY A BENTHIC DISTURBANCE? A Thesis by AMANDA D. VAN DIGGELEN Submitted to the Office of Graduate and Professional Studies of Texas A&M University and the Graduate Faculty of The Texas A&M University – Corpus...

Van Diggelen, Amanda

2014-05-07T23:59:59.000Z

403

Analysis of two basic variables of timeout  

E-Print Network (OSTI)

in reducing the rate of a designated behavior. Timeout from positive reinforcement is a behavior modification technique in which positive reinforcers are withdrawn for a period of time following a target response (White, Nielsen, and Johnson, 1972... variable (White, Nielsen, and Johnson, 1972) did not reach a decisive conclusion because of a sequencing problem in the method. The effects of three different timeout durations were investigated in a group of 20 retarded, institution- alized subjects...

Zella, William Francis

2012-06-07T23:59:59.000Z

404

HVAC's Variable Refrigerant Flow (VRF) Technology  

E-Print Network (OSTI)

1 Comfort by Design Steve Jones Commercial Sales Manager for Mitsubishi Southwest Business Unit HVAC?s Variable Refrigerant Flow (VRF) Technology HVAC Industry Overview HVAC Market Dollar Volume $18 Billion Source:;NABH Research....2M Systems Ductless is a small percent of the U.S. HVAC market but current building and energy usage trends indicate a large growth opportunity Determining the Proper Application Worldwide Usage-Opportunity Window Unitary Chillers...

Jones, S.

2012-01-01T23:59:59.000Z

405

Intensive Variables & Nanostructuring in Magnetostructural Materials  

SciTech Connect

Over the course of this project, fundamental inquiry was carried out to investigate, understand and predict the effects of intensive variables, including the structural scale, on magnetostructural phase transitions in the model system of equiatomic FeRh. These transitions comprise simultaneous magnetic and structural phase changes that have their origins in very strong orbital-lattice coupling and thus may be driven by a plurality of effects.

Lewis, Laura

2014-08-13T23:59:59.000Z

406

Regelation: why does ice melt under pressure?  

E-Print Network (OSTI)

Unlike other unusual materials whose bonds contract under compression, the O:H nonbond undergoes contraction and the H-O bond elongation towards O:H and H-O length symmetry in water and ice. The energy drop of the H-O bond dictates the melting point Tm depression of ice. Once the pressure is relieved, the O:H-O bond fully recovers its initial state, resulting in Regelation.

Sun, Chang Q

2015-01-01T23:59:59.000Z

407

Low-Cost Fiber Optic Pressure Sensor  

DOE Patents (OSTI)

The size and cost of fabricating fiber optic pressure sensors is reduced by fabricating the membrane of the sensor in a non-planar shape. The design of the sensors may be made in such a way that the non-planar membrane becomes a part of an air-tight cavity, so as to make the membrane resilient due to the air-cushion effect of the air-tight cavity. Such non-planar membranes are easier to make and attach.

Sheem, Sang K. (Pleasanton, CA)

2003-07-22T23:59:59.000Z

408

Low-Cost Fiber Optic Pressure Sensor  

DOE Patents (OSTI)

The size and cost of fabricating fiber optic pressure sensors is reduced by fabricating the membrane of the sensor in a non-planar shape. The design of the sensors may be made in such a way that the non-planar membrane becomes a part of an air-tight cavity, so as to make the membrane resilient due to the air-cushion effect of the air-tight cavity. Such non-planar membranes are easier to make and attach.

Sheem, Sang K. (Pleasanton, CA)

2004-05-18T23:59:59.000Z

409

An investigation of convergence pressure methods  

E-Print Network (OSTI)

of carbon dioxide, hydrogen sulfide, nitrogen, hydrocarbons having molecular weights from methane through hexane, and the remainder of the hydrocarbons are lumped into a single pseudocomponent G7+. Butane and pentane are further split into iso and normal... of Mixtures Versus Saturation Pressure Number of Mixtures Versus Temperature 55 56 10 Number of Mixtures Versus Mole Fraction of Carbon Dioxide 57 Number of Mixtures Versus Mole Fraction of Hydrogen Sulfide 12 Number of Mixtures Versus Mole Fraction...

Wattenbarger, Robert Chick

1986-01-01T23:59:59.000Z

410

Surveillance Guide - OSS 19.4 Pressure Safety  

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

PRESSURE SAFETY PRESSURE SAFETY 1.0 Objective The objective of this surveillance is to evaluate the contractor's implementation of programs to ensure the integrity of pressure vessels and minimize risks from failure of vessels to the public and to workers. Facility Representatives will examine the installed configuration of pressure vessels, observe pressure testing and review documentation associated with maintenance or repair of pressure vessels. In performing the surveillance, Facility Representatives will examine implementation of applicable DOE requirements and best practices. 2.0 References 2.1 DOE 5480.4, Environmental Protection, Safety and Health Protection Standards 2.2 DOE 5483.1A, Occupational Safety and Health Programs

411

Globally competitive variable-speed wind turbines  

SciTech Connect

This paper focuses on the design issues which must be addressed if variable-speed wind turbines are to compete in the global marketplace. The paper examines how component-specific design decisions must be made on a system level if an optimized system is to be the result. The relationships among the blades, the generator and the utility interface are considered in detail, using the conceptual design of a 12 kW variable-speed wind turbine (the AOC 8/12) as a running example. The turbine is based on a direct-drive variable-reluctance generator (VRG), a single- or three-phase utility interface as appropriate, and a three-bladed rotor with fixed pitch. A preliminary turbine specification is provided, along with candidate power-speed curves and annual energy output. This paper documents the continuing development and commercialization of this technology which is being taken from the proof-of-concept stage and is now headed for field testing.

Torrey, D.A. [Rensselaer Polytechnic Institute, Troy, NY (United States); Childs, S.E.; Johnson, B.; Carter, J. [Atlantic Orient Corp., Norwich, VT (United States)

1995-12-31T23:59:59.000Z

412

Free Floating Atmospheric Pressure Ball Plasmas  

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

Free-Floating Atmospheric Pressure Ball Plasmas Free-Floating Atmospheric Pressure Ball Plasmas G. A. Wurden, Z. Wang, C. Ticos Los Alamos National Laboratory L Al NM 87545 USA Los Alamos, NM 87545 USA C. J. v. Wurden Los Alamos High School L Al NM 87544 Los Alamos, NM 87544 Presented at the PPPL Colloquium Sept. 17, 2008 U N C L A S S I F I E D Operated by the Los Alamos National Security, LLC for the DOE/NNSA LA-UR-08-06284 Outline of this talk *A discussion of ball lightning reports in nature *How can ball plasmas be made in the laboratory? *Detailed experiments on long lived free floating *Detailed experiments on long-lived free-floating atmospheric pressure ball plasmas C i f l b b ll l i h "b ll *Comparison of laboratory ball plasmas with "ball lightning" *Summary U N C L A S S I F I E D Operated by the Los Alamos National Security, LLC for the DOE/NNSA

413

Ram Pressure Stripping in Clusters and Groups  

E-Print Network (OSTI)

Ram pressure stripping is an important process in the evolution of both dwarf galaxies and large spirals. Large spirals are severely stripped in rich clusters and may be mildly stripped in groups. Dwarf galaxies can be severely stripped in both clusters and groups. A model is developed that describes the stripping of a satellite galaxy's outer H \\textsc{i} disk and hot galactic halo. The model can be applied to a wide range of environments and satellite galaxy masses. Whether ram pressure stripping of the outer disk or hot galactic halo occurs is found to depend primarily on the ratio of the satellite galaxy mass to the mass of the host group or cluster. How the effectiveness of ram pressure stripping depends on the density of the inter-group gas, the dark matter halo concentrations, and the scale lengths and masses of the satellite components is explored. The predictions of the model are shown to be well matched to H \\textsc{i} observations of spirals in a sample of nearby clusters. The model is used to predict the range of H \\textsc{i} gas fractions a satellite of mass $M_{v,sat}$ can lose orbiting in a cluster of mass $M_{v,gr}$.

J. A. Hester

2006-10-03T23:59:59.000Z

414

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

415

A University Consortium on Efficient and Clean High-Pressure...  

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

Efficient and Clean High-Pressure, Lean Burn (HPLB) Engines A University Consortium on Efficient and Clean High-Pressure, Lean Burn (HPLB) Engines 2010 DOE Vehicle Technologies and...

416

DOE Hydrogen Delivery High-Pressure Tanks and Analysis Project...  

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

Delivery High-Pressure Tanks and Analysis Project Review Meeting DOE Hydrogen Delivery High-Pressure Tanks and Analysis Project Review Meeting On February 8-9, 2005, the Department...

417

Energy Savings from Floating Head Pressure in Ammonia Refrigeration Systems  

E-Print Network (OSTI)

This paper presents case studies of two moderately sized ammonia refrigeration systems retrofitted for floating head pressure control. It also presents a parametric analysis to assist in selecting appropriate pressures in an ammonia refrigeration...

Barrer, P. J.; Jones, S. M.

418

Near-Ground Pressure and Wind Measurements in Tornadoes  

Science Journals Connector (OSTI)

Since the spring of 2002, tornadoes were sampled on nine occasions using Hardened In-Situ Tornado Pressure Recorder probes, video probes, and mobile mesonet instrumentation. This study describes pressure and, in some cases, velocity data obtained ...

Christopher D. Karstens; Timothy M. Samaras; Bruce D. Lee; William A. Gallus Jr.; Catherine A. Finley

2010-07-01T23:59:59.000Z

419

Sandia National Laboratories: High-Pressure and High-Temperature...  

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

ClimateECClimateCarbon CaptureHigh-Pressure and High-Temperature Neutron Reflectometry Cell for Solid-Fluid Interface Studies High-Pressure and High-Temperature Neutron...

420

Electrical resistance of Manganin under high static pressures  

Science Journals Connector (OSTI)

The electrical resistance of manganin was measured under pressures up to 220 kbar at room temperature. The pressure was produced by means of a multianvil apparatus using semisintered magnesia for the pressure medium and was calibrated against well?known fixed points. Obtained results show a linear relationship between the resistance and pressure up to 180 kbar with good reproducibility. The pressure coefficient of resistance turns out to be (2.322±0.008) ×10?3 kbar?1 which is in close agreement with the value obtained under hydrostatic conditions. Manganin can be satisfactorily used as a pressure gauge for a high?pressure experiment using a solidpressure medium. The deviation from the linearity observed above 180 kbar is ascribed to either an intrinsic property of Manganin or the uncertainty of the fixed point adopted. If the linearity is assumed above 180 kbar the transition pressure of GaP is estimated to be 206±2 kbar.

N. Fujioka; O. Mishima; S. Endo; N. Kawai

1978-01-01T23:59:59.000Z

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.


421

Iterative Boltzmann plot method for temperature and pressure determination in a xenon high pressure discharge lamp  

SciTech Connect

The Boltzmann plot method allows to calculate plasma temperatures and pressures if absolutely calibrated emission coefficients of spectral lines are available. However, xenon arcs are not very well suited to be analyzed this way, as there are only a limited number of lines with atomic data available. These lines have high excitation energies in a small interval between 9.8 and 11.5 eV. Uncertainties in the experimental method and in the atomic data further limit the accuracy of the evaluation procedure. This may result in implausible values of temperature and pressure with inadmissible uncertainty. To omit these shortcomings, an iterative scheme is proposed that is making use of additional information about the xenon fill pressure. This method is proved to be robust against noisy data and significantly reduces the uncertainties. Intentionally distorted synthetic data are used to illustrate the performance of the method, and measurements performed on a laboratory xenon high pressure discharge lamp are analyzed resulting in reasonable temperatures and pressures with significantly reduced uncertainties.

Zalach, J.; Franke, St. [INP Greifswald, Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany)

2013-01-28T23:59:59.000Z

422

Forum Agenda: International Hydrogen Fuel and Pressure Vessel Forum  

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

Agenda for the International Hydrogen Fuel and Pressure Vessel Forum held Sept. 27-29, 2010, in Beijing, China

423

Pressurized tundish for controlling a continuous flow of molten metal  

DOE Patents (OSTI)

A pressurized tundish for controlling a continous flow of molten metal characterized by having a pair of principal compartments, one being essentially unpressurized and receiving molten metal introduced thereto, and the other being adapted for maintaining a controlled gaseous pressure over the surface of the fluid metal therein, whereby, by controlling the pressure within the pressurized chamber, metal exiting from the tundish is made to flow continually and at a controlled rate.

Lewis, Thomas W. (964 Cork Dr., Bethel Park, PA 15102); Hamill, Jr., Paul E. (R.D. #1, Box 173A1, Jeannette, PA 15644); Ozgu, Mustafa R. (790 Yorkshire Rd., Bethlehem, PA 18017); Padfield, Ralph C. (1918 Paul Ave., Bethlehem, PA 18018); Rego, Donovan N. (1703 W. Brown St., Allentown, PA 18104); Brita, Guido P. (3225 Edna Terrace Ave., Bethlehem, PA 18017)

1990-01-01T23:59:59.000Z

424

Field measurements of earth pressure on a cantilever retaining wall  

E-Print Network (OSTI)

. The measurements were made before and after backfilling for a duration of 385 days. The effects of a clay surcharge were studied. The total thrust of the measured lateral earth pressures was com- pared to total thrust determined from a Culmann graphical... to bearing pressures calculated by conventional methods. The measured bearing pressures compared reasonably well with the calculated pressures. Wall movement data indicated that the wall tilted or rotated toward the backfill during sand backfilling...

Schulze, Larry Wayne

2012-06-07T23:59:59.000Z

425

Pressurized tundish for controlling a continuous flow of molten metal  

DOE Patents (OSTI)

A pressurized tundish for controlling a continuous flow of molten metal is characterized by having a pair of principal compartments, one being essentially unpressurized and receiving molten metal introduced thereto, and the other being adapted for maintaining a controlled gaseous pressure over the surface of the fluid metal therein, whereby, by controlling the pressure within the pressurized chamber, metal exiting from the tundish is made to flow continually and at a controlled rate. 1 fig.

Lewis, T.W.; Hamill, P.E. Jr.; Ozgu, M.R.; Padfield, R.C.; Rego, D.N.; Brita, G.P.

1990-07-24T23:59:59.000Z

426

Optimisation of transient response of a gasoline engine with variable geometry turbine turbocharger  

Science Journals Connector (OSTI)

ABSTRACT Maintaining transient torque response is challenging on turbocharged engines because of the period of time required to accelerate the turbocharger. Variable Geometry Turbine (VGT) turbochargers offer a route to improve the transient response. In order to explore the transient operation without any limitation imposed by the production control strategy, an on line search was conducted using a series of open loop actuator trajectories applied to a VGT turbocharger installed on a gasoline engine. The trade-off between the responses in different stages in the transient event has been illustrated. The time required to reach 50% of maximum torque rise (T50) was improved by up to 0.54 s (35.5%) whilst the turbocharger acceleration was maintained. Fully closing the VGT resulted in high exhaust back pressure and low volumetric efficiency. This suggests that a simple boost pressure feedback control will likely not deliver optimised performance due to the excessive exhaust back pressure, reducing the available brake torque during the early part of the transient. Therefore, a model based control strategy may be required.

H. Tang; S. Akehurst; C.J. Brace; S. Garrett; L. Smith

2014-01-01T23:59:59.000Z

427

Airflow regulation in variable-speed systems for residential HVAC applications  

SciTech Connect

In the majority of heating, ventilating, and air-conditioning (HVAC) systems, air is the final medium for adding or extracting heat from or to the space to be air conditioned. Air is heated by passing it over a heat transfer device called a coil, which is a heat exchanger with air on the outside and the primary heating/cooling medium (water, steam, electricity, refrigerant, etc.) on the inside. One of the major factors determining heat transfer is the airflow rate, which can be controlled by mechanical means or by controlling the speed of the fan. Centrifugal fans driven by single-speed induction motors traditionally have been used in the JVAC industry but have an airflow characteristic that depends on the static pressure seen by the system. Variable-speed systems are starting to emerge as a strong alternative to traditional systems because of their ability to match the demand of the air-conditioned space, resulting in higher efficiencies and higher comfort. System efficiency can be improved by constraining the range of airflows provided by the fan or blower system in response to system pressure, that is, by controlling the airflow over the heat exchanger. This paper presents a method to regulate airflow independent of the static pressure and without the need for airflow sensors.

Becerra, R.C.; Beifus, B.L. [General Electric Co., Fort Wayne, IN (United States)

1996-11-01T23:59:59.000Z

428

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

E-Print Network (OSTI)

Volume Systems.? Proceedings of ACEEE 1994 Summer Study on Energy Efficiency in Buildings, Vol. 5, pp. 219-223. 3. Liu M., Zhu Y., Claridge D.E., and White E., 1997. ?Impact of Static Pressure Set Level on HVAC Energy Consumption and Indoor... Volume Systems.? Proceedings of ACEEE 1994 Summer Study on Energy Efficiency in Buildings, Vol. 5, pp. 219-223. 3. Liu M., Zhu Y., Claridge D.E., and White E., 1997. ?Impact of Static Pressure Set Level on HVAC Energy Consumption and Indoor...

Liu, M.

2002-01-01T23:59:59.000Z

429

Thermoelectric Power of Germanium. Effect of 2000-atm Pressure  

Science Journals Connector (OSTI)

The effect of 2000-atm hydrostatic pressure on the thermoelectric power of n-and p-type germanium has been measured between 120 and 280°K. After spurious effects of heat conduction in the pressure medium were eliminated, the results could be explained in terms of pressure changes in the phonon-drag contribution.

P. J. Freud and G. M. Rothberg

1967-02-15T23:59:59.000Z

430

Measuring the pressures across microfluidic droplets with an optical tweezer  

E-Print Network (OSTI)

Measuring the pressures across microfluidic droplets with an optical tweezer Yuhang Jin,1 Antony a novel technique that enables pressure measurements to be made in microfluidic chips using optical trapping. Pressure differentials across droplets in a microfluidic channel are determined by monitoring

431

Pressure effects on lipids and bio-membrane assemblies  

Science Journals Connector (OSTI)

Pressure can play a key role in probing the structure and dynamics of membrane assemblies, and is also critical to the biology and adaptation of deep-sea organisms. This article presents an overview of the effect of pressure on the structure of membranes and recent developments in high-pressure instrumentation.

Brooks, N.J.

2014-09-23T23:59:59.000Z

432

Pressure Differential Analysis of a Laboratory Animal Room  

E-Print Network (OSTI)

differential can prevent air flow from a low pressure region to a high pressure region. We tested whether the differential pressure is reasonable to regulate the code between the indoors and outdoors, and among laboratory animal rooms, so as to provide a...

Jiang, X.; Liu, Z.; Yoshida, H.; Tang, B.

2006-01-01T23:59:59.000Z

433

Finite-Pressure-Gradient Influences on Ideal Spheromak Equilibrium  

Science Journals Connector (OSTI)

Spatially resolved measurements of the magnetic field of a spheromak have been analyzed and compared with expectations for the ratio of j?B from the pressure-gradient-free Taylor model and a model with pressure due to Morikawa. Better agreement is found with the model containing finite pressure.

G. W. Hart; C. Chin-Fatt; A. W. DeSilva; G. C. Goldenbaum; R. Hess; R. S. Shaw

1983-10-24T23:59:59.000Z

434

Northern Tool + Equipment Find the Right Fitting for Your Pressure Washer at Northern Tool! NorthernTool.com/PressureWashers Pristine Pressure Pressure/power washing in Maryland Vinyl siding cleaned, decks cleaned www.pristinepressure.com  

E-Print Network (OSTI)

ability to clean while saving on our most important resources, water and energy." In recognition! NorthernTool.com/PressureWashers Pristine Pressure Pressure/power washing in Maryland Vinyl siding cleaned, decks cleaned www.pristinepressure.com Siding Cleaning Bring back the life to your siding! Estimates

Sóbester, András

435

RF BREAKDOWN STUDIES USING PRESSURIZED CAVITIES  

SciTech Connect

Many present and future particle accelerators are limited by the maximum electric gradient and peak surface fields that can be realized in RF cavities. Despite considerable effort, a comprehensive theory of RF breakdown has not been achieved and mitigation techniques to improve practical maximum accelerating gradients have had only limited success. Part of the problem is that RF breakdown in an evacuated cavity involves a complex mixture of effects, which include the geometry, metallurgy, and surface preparation of the accelerating structures and the make-up and pressure of the residual gas in which plasmas form. Studies showed that high gradients can be achieved quickly in 805 MHz RF cavities pressurized with dense hydrogen gas, as needed for muon cooling channels, without the need for long conditioning times, even in the presence of strong external magnetic fields. This positive result was expected because the dense gas can practically eliminate dark currents and multipacting. In this project we used this high pressure technique to suppress effects of residual vacuum and geometry that are found in evacuated cavities in order to isolate and study the role of the metallic surfaces in RF cavity breakdown as a function of magnetic field, frequency, and surface preparation. One of the interesting and useful outcomes of this project was the unanticipated collaborations with LANL and Fermilab that led to new insights as to the operation of evacuated normal-conducting RF cavities in high external magnetic fields. Other accomplishments included: (1) RF breakdown experiments to test the effects of SF6 dopant in H2 and He gases with Sn, Al, and Cu electrodes were carried out in an 805 MHz cavity and compared to calculations and computer simulations. The heavy corrosion caused by the SF6 components led to the suggestion that a small admixture of oxygen, instead of SF6, to the hydrogen would allow the same advantages without the corrosion in a practical muon beam line. (2) A 1.3 GHz RF test cell capable of operating both at high pressure and in vacuum with replaceable electrodes was designed, built, and power tested in preparation for testing the frequency and geometry effects of RF breakdown at Argonne National Lab. At the time of this report this cavity is still waiting for the 1.3 GHz klystron to be available at the Wakefield Test Facility. (3) Under a contract with Los Alamos National Lab, an 805 MHz RF test cavity, known as the All-Seasons Cavity (ASC), was designed and built by Muons, Inc. to operate either at high pressure or under vacuum. The LANL project to use the (ASC) was cancelled and the testing of the cavity has been continued under the grant reported on here using the Fermilab Mucool Test Area (MTA). The ASC is a true pillbox cavity that has performed under vacuum in high external magnetic field better than any other and has demonstrated that the high required accelerating gradients for many muon cooling beam line designs are possible. (4) Under ongoing support from the Muon Acceleration Program, microscopic surface analysis and computer simulations have been used to develop models of RF breakdown that apply to both pressurized and vacuum cavities. The understanding of RF breakdown will lead to better designs of RF cavities for many applications. An increase in the operating accelerating gradient, improved reliability and shorter conditioning times can generate very significant cost savings in many accelerator projects.

Johnson, Rolland

2014-09-21T23:59:59.000Z

436

Time Variability of the "Quiet" Sun Observed  

Science Journals Connector (OSTI)

The Transition Region and Coronal Explorer (TRACE) observed a "quiet-Sun" region on 1999 February 17 from 02:15 UT to 3:00 UT with full resolution (05 pixel size), high cadence (125 s), and deep exposures (65 and 46 s) in the 171 Ĺ and 195 Ĺ wavelengths. We start our investigation of the time variability of "quiet-Sun" images with a detailed analysis of instrumental and nonsolar effects, such as orbital temperature variations, filtering of particle radiation spikes, spacecraft pointing drift, and solar rotation tracking. We quantify the magnitude of various noise components (photon Poisson statistics, data digitization, data compression, and readout noise) and establish an upper limit for the data noise level, above which temporal variability can safely be attributed to solar origin. We develop a pattern recognition code that extracts spatiotemporal events with significant variability, yielding a total of 3131 events in 171 Ĺ and 904 events in 195 Ĺ. We classify all 904 events detected in 195 Ĺ according to flarelike characteristics and establish a numerical flare criterion based on temporal, spatial, and dynamic cross-correlation coefficients between the two observed temperatures (0.9 and 1.4 MK). This numerical criterion matches the visual flare classification in 83% of the cases and can be used for automated flare search. Using this flare discrimination criterion we find that only 35% (and 25%) of the events detected in 171 (and 195) Ĺ represent flarelike events. The discrimination of flare events leads to a frequency distribution of peak fluxes, N(?F) ? ?F-1.83±0.07 at 195 Ĺ, which is significantly flatter than the distribution of all events. A sensitive discrimination criterion of flare events is therefore important for microflare statistics and for conclusions on their occurrence rate and efficiency for coronal heating.

Markus J. Aschwanden; Richard W. Nightingale; Ted D. Tarbell; C. J. Wolfson

2000-01-01T23:59:59.000Z

437

Impact of variable RBE on proton fractionation  

SciTech Connect

Purpose: To explore the impact of variable proton relative biological effectiveness (RBE) on dose fractionation for clinically relevant situations. A generic RBE = 1.1 is generally used for isoeffect calculations, while experimental studies showed that proton RBE varies with tissue type, dose, and linear energy transfer (LET). Methods: An analytical expression for the LET and {alpha}/{beta} dependence of the linear-quadratic (LQ) model has been used for proton simulations in parallel with the assumption of a generic RBE = 1.1. Calculations have been performed for ranges of LET values and fractionation sensitivities to describe clinically relevant cases, such as the treatment of head and neck and prostate tumors. Isoeffect calculations were compared with predictions from a generic RBE value and reported clinical results. Results: The generic RBE = 1.1 appears to be a reasonable estimate for the proton RBE of rapidly growing tissues irradiated with low LET radiation. However, the use of a variable RBE predicts larger differences for tissues with low {alpha}/{beta} (both tumor and normal) and at low doses per fraction. In some situations these differences may appear in contrast to the findings from photon studies highlighting the importance of accurate accounting for the radiobiological effectiveness of protons. Furthermore, the use of variable RBE leads to closer predictions to clinical results. Conclusions: The LET dependence of the RBE has a strong impact on the predicted effectiveness of fractionated proton radiotherapy. The magnitude of the effect is modulated by the fractionation sensitivity and the fractional dose indicating the need for accurate analyses both in the target and around it. Care should therefore be employed for changing clinical fractionation patterns or when analyzing results from clinical studies for this type of radiation.

Dasu, Alexandru; Toma-Dasu, Iuliana [Department of Radiation Physics UHL, County Council of Oestergoetland, 581 85 Linkoeping (Sweden) and Radiation Physics, Department of Medical and Health Sciences, Faculty of Health Sciences, Linkoeping University, 581 83 Linkoeping (Sweden); Medical Radiation Physics, Stockholm University and Karolinska Institute, 171 76 Stockholm (Sweden)

2013-01-15T23:59:59.000Z

438

High-pressure coal fuel processor development  

SciTech Connect

The objective of Subtask 1.1 Engine Feasibility was to conduct research needed to establish the technical feasibility of ignition and stable combustion of directly injected, 3,000 psi, low-Btu gas with glow plug ignition assist at diesel engine compression ratios. This objective was accomplished by designing, fabricating, testing and analyzing the combustion performance of synthesized low-Btu coal gas in a single-cylinder test engine combustion rig located at the Caterpillar Technical Center engine lab in Mossville, Illinois. The objective of Subtask 1.2 Fuel Processor Feasibility was to conduct research needed to establish the technical feasibility of air-blown, fixed-bed, high-pressure coal fuel processing at up to 3,000 psi operating pressure, incorporating in-bed sulfur and particulate capture. This objective was accomplished by designing, fabricating, testing and analyzing the performance of bench-scale processors located at Coal Technology Corporation (subcontractor) facilities in Bristol, Virginia. These two subtasks were carried out at widely separated locations and will be discussed in separate sections of this report. They were, however, independent in that the composition of the synthetic coal gas used to fuel the combustion rig was adjusted to reflect the range of exit gas compositions being produced on the fuel processor rig. Two major conclusions resulted from this task. First, direct injected, ignition assisted Diesel cycle engine combustion systems can be suitably modified to efficiently utilize these low-Btu gas fuels. Second, high pressure gasification of selected run-of-the-mine coals in batch-loaded fuel processors is feasible. These two findings, taken together, significantly reduce the perceived technical risks associated with the further development of the proposed coal gas fueled Diesel cycle power plant concept.

Greenhalgh, M.L.

1992-11-01T23:59:59.000Z

439

Adhesive bonding using variable frequency microwave energy  

DOE Patents (OSTI)

Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy.

Lauf, Robert J. (Oak Ridge, TN); McMillan, April D. (Knoxville, TN); Paulauskas, Felix L. (Oak Ridge, TN); Fathi, Zakaryae (Cary, NC); Wei, Jianghua (Raleigh, NC)

1998-01-01T23:59:59.000Z

440

Adhesive bonding using variable frequency microwave energy  

DOE Patents (OSTI)

Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

1998-09-08T23:59:59.000Z

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

Adhesive bonding using variable frequency microwave energy  

DOE Patents (OSTI)

Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

1998-08-25T23:59:59.000Z

442

Dynamical variables in Gauge-Translational Gravity  

E-Print Network (OSTI)

Assuming that the natural gauge group of gravity is given by the group of isometries of a given space, for a maximally symmetric space we derive a model in which gravity is essentially a gauge theory of translations. Starting from first principles we verify that a nonlinear realization of the symmetry provides the general structure of this gauge theory, leading to a simple choice of dynamical variables of the gravity field corresponding, at first order, to a diagonal matrix, whereas the non-diagonal elements contribute only to higher orders.

J. Julve; A. Tiemblo

2010-07-02T23:59:59.000Z

443

A variable parameter thermionic energy converter  

E-Print Network (OSTI)

A VARIABLE PARAMETER THERMIONIC ENERGY CONVERTER A Thesis By Bobby Joe Bragg Submitted to the Graduate School of the Texas A 8c M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August, 1967 Major... LIST OF FIGURES FIGURE 1. SIMPLE SCHEMATIC OF A THERMIONIC CONVERTER PAGE 2. POWER VS SPACING WITH A MINIMUM POWER POINT 3. POWER VS SPACING WITH NO MINIMUM POWER POINT 4. CONVERTER MOTIVE DIAGRAM~ O'E = 5. CONVERTER MOTIVE DIAGRAM~ 6. CONVERTER...

Bragg, Bobby Joe

1967-01-01T23:59:59.000Z

444

The future of massive variability searches  

E-Print Network (OSTI)

This is a personal review of various issues related to massive photometric and astrometric searches. A complete inventory of variable stars down to almost any magnitude limit will improve our understanding of the stellar evolution and the galactic structure. A search for detached eclipsing binaries will improve the distance scale, the value of the Hubble constant, and the age of the oldest stars. A search for supernovae will help the determination of cosmological parameters Omega and Lambda. A search for microlensing events will provide insight into the stellar mass function, dark matter, and may lead to a discovery of earth-mass planets.

Paczynski, B

1996-01-01T23:59:59.000Z

445

Crystal diffraction lens with variable focal length  

DOE Patents (OSTI)

A method and apparatus for altering the focal length of a focusing element of one of a plurality of pre-determined focal lengths by changing heat transfer within selected portions of the element by controlled quantities is disclosed. Control over heat transfer is accomplished by manipulating one or more of a number of variables, including: the amount of heat or cold applied to surfaces; type of fluids pumped through channels for heating and cooling; temperatures, directions of flow and rates of flow of fluids; and placement of channels. 19 figures.

Smither, R.K.

1991-04-02T23:59:59.000Z

446

Chi-Variable-Speed-of-Light Cosmologies  

E-Print Network (OSTI)

Variable-Speed-of-Light (VSL) cosmologies are currently attracting much interest as a possible alternative to cosmological inflation. We discuss the fundamental geometrodynamic aspects of VSL cosmologies, and provide several alternative implementations. These implementations provide a large class of VSL cosmologies that pass the zeroth-order consistency tests of being compatible with both classical Einstein gravity and low-energy particle physics. While they solve the ``kinematic'' puzzles as well as inflation does, VSL cosmologies typically do not solve the flatness problem since in their purest form no violation of the strong energy condition occurs. Nevertheless, these models are easy to unify with inflation.

Stefano Liberati; Bruce A. Bassett; Carmen Molina-Paris; Matt Visser

2000-01-27T23:59:59.000Z

447

Hyperosmolar Therapy for Raised Intracranial Pressure  

Science Journals Connector (OSTI)

...undertaken. Attempts to decompress the cranial contents by removing parts of the skull after traumatic brain injury have lowered intracranial pressure but have not improved the outcome, as compared with standard care. Several other interventions, in addition to hyperosmolar therapy, may be useful in the management... Foreword This Journal feature begins with a case vignette that includes a therapeutic recommendation. A discussion of the clinical problem and the mechanism of benefit of this form of therapy follows. Major clinical studies, the clinical use of this ...

Ropper A.H.

2012-08-23T23:59:59.000Z

448

Multidimensional gravitational model with anisotropic pressure  

E-Print Network (OSTI)

We consider the gravitational model with additional spatial dimensions and anisotropic pressure which is nonzero only in these dimensions. Cosmological solutions in this model include accelerated expansion of the Universe at late age of its evolution and dynamical compactification of extra dimensions. This model describes observational data for Type Ia supernovae on the level or better than the $\\Lambda$CDM model. We analyze two equations of state resulting in different predictions for further evolution, but in both variants the acceleration epoch is finite.

O. A. Grigorieva; G. S. Sharov

2014-02-18T23:59:59.000Z

449

Combustor oscillating pressure stabilization and method  

DOE Patents (OSTI)

High dynamic pressure oscillations in hydrocarbon-fueled combustors typically occur when the transport time of the fuel to the flame front is at some fraction of the acoustic period. These oscillations are reduced to acceptably lower levels by restructuring or repositioning the flame front in the combustor to increase the transport time. A pilot flame front located upstream of the oscillating flame and pulsed at a selected frequency and duration effectively restructures and repositions the oscillating flame in the combustor to alter the oscillation-causing transport time.

Gemmen, Randall S. (Morgantown, WV); Richards, George A. (Morgantown, WV); Yip, Mui-Tong Joseph (Morgantown, WV); Robey, Edward H. (Westover, WV); Cully, Scott R. (Morgantown, WV); Addis, Richard E. (Smithfield, PA)

1998-01-01T23:59:59.000Z

450

Second-generation pressurized fluidized bed combustion  

SciTech Connect

Under the sponsorship of the United States Department of Energy, Foster Wheeler Corporation is developing second-generation pressurized fluidized bed combustion (PFBC) power plant technology that will enable this type of plant to operate with net plant efficiencies in the range of 43 to 46 percent (based on the higher heating value of the coal), with a reduction in the cost of electricity of at least 20 percent. A three-phase program is under way. Its scope encompasses the conceptual design of a commercial plant through the process of gathering needed experimental test data to obtain design parameters.

Wolowodiuk, W.; Robertson, A.

1992-01-01T23:59:59.000Z

451

Second-generation pressurized fluidized bed combustion  

SciTech Connect

Under the sponsorship of the United States Department of Energy, Foster Wheeler Corporation is developing second-generation pressurized fluidized bed combustion (PFBC) power plant technology that will enable this type of plant to operate with net plant efficiencies in the range of 43 to 46 percent (based on the higher heating value of the coal), with a reduction in the cost of electricity of at least 20 percent. A three-phase program is under way. Its scope encompasses the conceptual design of a commercial plant through the process of gathering needed experimental test data to obtain design parameters.

Wolowodiuk, W.; Robertson, A.

1992-05-01T23:59:59.000Z

452

High-pressure liquid chromatographic gradient mixer  

DOE Patents (OSTI)

A gradient mixer effects the continuous mixing of any two miscible solvents without excessive decay or dispersion of the resultant isocratic effluent or of a linear or exponential gradient. The two solvents are fed under low or high pressure by means of two high performance liquid chromatographic pumps. The mixer comprises a series of ultra-low dead volume stainless steel tubes and low dead volume chambers. The two solvent streams impinge head-on at high fluxes. This initial nonhomogeneous mixture is then passed through a chamber packed with spirally-wound wires which cause turbulent mixing thereby homogenizing the mixture with minimum band-broadening.

Daughton, C.G.; Sakaji, R.H.

1982-09-08T23:59:59.000Z

453

HIGH PRESSURE COAL COMBUSTION KINETICS PROJECT  

SciTech Connect

SRI has completed the NBFZ test program, made modification to the experimental furnace for the HPBO test. The NBFZ datasets provide the information NEA needs to simulate the combustion and fuel-N conversion with detailed chemical reaction mechanisms. BU has determined a linear swell of 1.55 corresponding to a volumetric increase of a factor of 3.7 and a decrease in char density by the same factor. These results are highly significant, and indicate significantly faster burnout at elevated pressure due to the low char density and large diameter.

Chris Guenther, Ph.D.

2003-01-28T23:59:59.000Z

454

Thermodynamic analysis of a stand-alone reverse osmosis desalination system powered by pressure retarded osmosis  

Science Journals Connector (OSTI)

Abstract In this study, a methodology is developed to assess the feasibility of a reverse osmosis (RO) desalination system powered by a stand-alone salinity driven pressure retarded osmosis (PRO) technology. First, the proposed hybrid RO–PRO system is analysed as a thermodynamic cycle and its feasibility is mathematically interpreted using a feasible condition (FC) number, several dimensionless operational variables and a number of constraints to represent the objective of zero brine discharge. Then, a study of the stand-alone feasibility of a hybrid seawater RO–PRO system is carried out. The results show that lower RO water recovery and higher dimensionless flow rate improve the stand-alone feasibility of the system. A subsystem, a look inside the PRO, is developed to study the applied pressure and the required membrane area to achieve the operations with optimum FC numbers. It is found that the optimum applied hydraulic pressure is inversely proportional to the dimensionless flow rate in the feasible range of stand-alone operations and more area of membrane is required by a larger FC number. Finally, a case study of a selected operation is presented based on its energy performance, and two influencing factors, the inefficiency of the components and the salinity concentration of the feed water.

Wei He; Yang Wang; Adel Sharif; Mohammad Hasan Shaheed

2014-01-01T23:59:59.000Z

455

Intraseasonal variability in South America recorded in stable water isotopes  

E-Print Network (OSTI)

Intraseasonal variability in South America recorded in stable water isotopes Christophe Sturm,1 cores (South America) has illustrated the key role such archives can play in past climate South America, highlighting the internal atmospheric variability, as opposed to external forcing

Sturm, Christophe "Kristof"

456

Wave spectral energy variability in the northeast Peter D. Bromirski  

E-Print Network (OSTI)

Wave spectral energy variability in the northeast Pacific Peter D. Bromirski Integrative January 2005; published 8 March 2005. [1] The dominant characteristics of wave energy variability] s wave spectral energy components are considered separately. Empirical orthogonal function (EOF) analyses

Bromirski, Peter D.

457

Bayesian variable selection in clustering via dirichlet process mixture models  

E-Print Network (OSTI)

simultane- ously. I use Dirichlet process mixture models to define the cluster structure and to introduce in the model a latent binary vector to identify discriminating variables. I update the variable selection index using a Metropolis algorithm and obtain...

Kim, Sinae

2007-09-17T23:59:59.000Z

458

Atlantic Climate Variability and Predictability: A CLIVAR Perspective  

Science Journals Connector (OSTI)

Three interrelated climate phenomena are at the center of the Climate Variability and Predictability (CLIVAR) Atlantic research: tropical Atlantic variability (TAV), the North Atlantic Oscillation (NAO), and the Atlantic meridional overturning ...

J. W. Hurrell; M. Visbeck; A. Busalacchi; R. A. Clarke; T. L. Delworth; R. R. Dickson; W. E. Johns; K. P. Koltermann; Y. Kushnir; D. Marshall; C. Mauritzen; M. S. McCartney; A. Piola; C. Reason; G. Reverdin; F. Schott; R. Sutton; I. Wainer; D. Wright

2006-10-01T23:59:59.000Z

459

Effect of Pressure Transmission Lines on the Frequency Response of Pressure Transducers  

SciTech Connect

It is well known that the length and diameter of the transmission lines between a pressure transducer and the pressure source can significantly affect the dynamic frequency response of the transducer. A new lumped parameter model has been developed to predict the time and frequency response of any number of different transducers connected in parallel in a manifold. While the model is simple to apply, it can provide quantitative information given the transducer and transmission line characteristic parameters. More importantly, the model can be used to evaluate the measured, in-situ response. this provides the natural frequency and the effective damping which can then be used to generate a frequency response curve. The model is also useful for designing a new pressure transmission system, which will have the required frequency response. The model was qualified by comparison to measurements of the step-function pressure response of a number of different transducers and test installations. With the aid of the model, the system resonant frequency and damping can be determined. Additional damping can be added if necessary to prevent ringing of the signal and to assure an accurate pressure measurement with a flat frequency response. For all of the experimental systems evaluated in this work, the response at the natural frequency was significantly underdamped and ringing was observed. This means that to perform accurate measurements damping needs to be added to the system. It was observed that the use of flexible pressure lines versus hard lines does increase the damping and may therefore be useful in certain situations. Equations were developed to permit sizing an orifice to be added to the system to provide the necessary damping.

G.J. Kirouac

2000-11-13T23:59:59.000Z

460

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

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.


461

Fundamentals of High Pressure Combustion Chapter in High Pressure Processes in Chemical Engineering, Edited by Maximillian Lackner,  

E-Print Network (OSTI)

Fundamentals of High Pressure Combustion Chapter in High Pressure Processes in Chemical Engineering for more than 50 years and are expected to continue to do so [2]. Diesel engines obtain pressures as large as 60atm after ignition [3, 4, 5, 6, 7]. Figure 1 presents a schematic of diesel and gas turbine engine

Miller, Richard S.

462

Guidelines for Testing Pressure Canner Gauges County Extension Agents have offered annual pressure canner testing clinics so clientele  

E-Print Network (OSTI)

Guidelines for Testing Pressure Canner Gauges County Extension Agents have offered annual pressure canner testing clinics so clientele can get their dial gauges tested yearly ­ a practice strongly guidelines for pressure canner testing that have been established by the National Center for Home Food

463

On adaptive grid computations of variable stars  

SciTech Connect

We show that the use of an implicit adaptive-grid technique is an efficient and up-to-date approach for the calculations of radial oscillations in variable stars. We chose as an illustrative example the radiative envelope of an RR Lyrae variable. For the hydrostatic initial model we compare the Lagrangean ratioed zoning with an adaptive-grid rezoning. We show that the adaptive-grid yields an optimal distribution of the mesh points in the sense that the relevant physical features, the H{minus} and He 1{minus}, He 2{minus} ionization zones, are well resolved. For the hydrodynamical evolution we present the full-amplitude model for both the Lagrangean and adaptive-grid computations. We perform a detailed comparison and show that the adaptive-grid method yields limit cycle solutions that are substantially improved over the Lagrangean grid model. This is due to the fact that the Lagrangean mesh sweeps through the ionization zones twice during one oscillation period, whereas the adaptive-mesh resolves them and tracks them continuously. The results are, in particular, smooth radial velocity and light curves. Beyond a physically better defined solution we also observe larger time steps for the convergence towards the limit cycle and for the evolution during one period. 12 refs., 13 figs., 5 tabs.

Cox, A.N.; Deupree, R.G.; Gehmeyr, M.

1991-01-01T23:59:59.000Z

464

Dynamical dark energy or variable cosmological parameters?  

E-Print Network (OSTI)

One of the main aims in the next generation of precision cosmology experiments will be an accurate determination of the equation of state (EOS) for the dark energy (DE). If the latter is dynamical, the resulting barotropic index \\omega should exhibit a non-trivial evolution with the redshift. Usually this is interpreted as a sign that the mechanism responsible for the DE is related to some dynamical scalar field, and in some cases this field may behave non-canonically (phantom field). Present observations seem to favor an evolving DE with a potential phantom phase near our time. In the literature there is a plethora of dynamical models trying to describe this behavior. Here we show that the simplest option, namely a model with a variable cosmological term, \\Lambda=\\Lambda(t), leads in general to a non-trivial effective EOS, with index \\omega_e, which may naturally account for these data features. We prove that in this case there is always a ``crossing'' of the \\omega_e=-1 barrier near our time. We also show how this effect is modulated (or even completely controled) by a variable Newton's constant G=G(t).

Joan Sola; Hrvoje Stefancic

2005-12-21T23:59:59.000Z

465

Variably insulating portable heater/cooler  

DOE Patents (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

466

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

467

Variable Speed of Light Research Project Dave Schumann  

E-Print Network (OSTI)

Variable Speed of Light Research Project Dave Schumann Dr. Bharath Narayanan 21 September 2003 mathematics of the Variable Speed of Light (VSL) theory. In a paper titled, "A Time Varying Speed of Light of a variable speed of light in the early stages of the universe. They propose corrections to the cosmological

Zakharov, Vladimir

468

Development of Screenable Pressure Sensitive Adhesives  

SciTech Connect

An industrial research area of high activity in recent years has been the development of pressure sensitive adhesive (PSA) products that do not interfere with the processing of post-consumer waste. The problem of PSA contamination is arguably the most important technical challenge in expanding the use of recycled fiber. The presence of PSAs in recovered paper creates problems that reduce the efficiency of recycling and papermaking operations and diminish product quality. The widespread use of PSAs engineered to avoid these problems, often referred to as environmentally benign PSAs, could greatly increase the commercial viability of utilizing secondary fiber. Much of the research efforts in this area have focused on the development of PSAs that are designed for enhanced removal with cleaning equipment currently utilized by recycling plants. Most removal occurs at the pressure screens with the size and shape of residual contaminants in the process being the primary criteria for their separation. A viable approach for developing environmentally benign PSAs is their reformulation to inhibit fragmentation. The reduction of adhesives to small particles occurs almost exclusively during repulping; a process in which water and mechanical energy are used to swell and reduce paper products to their constituent fiber. Engineering PSA products to promote the formation of larger adhesive particles during repulping will greatly enhance their removal and reduce or eliminate their impact on the recycling process.

Steven J. Severtson

2003-11-29T23:59:59.000Z

469

Radiation effects on reactor pressure vessel supports  

SciTech Connect

The purpose of this report is to present the findings from the work done in accordance with the Task Action Plan developed to resolve the Nuclear Regulatory Commission (NRC) Generic Safety Issue No. 15, (GSI-15). GSI-15 was established to evaluate the potential for low-temperature, low-flux-level neutron irradiation to embrittle reactor pressure vessel (RPV) supports to the point of compromising plant safety. An evaluation of surveillance samples from the High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory (ORNL) had suggested that some materials used for RPV supports in pressurized-water reactors could exhibit higher than expected embrittlement rates. However, further tests designed to evaluate the applicability of the HFIR data to reactor RPV supports under operating conditions led to the conclusion that RPV supports could be evaluated using traditional method. It was found that the unique HFIR radiation environment allowed the gamma radiation to contribute significantly to the embrittlement. The shielding provided by the thick steel RPV shell ensures that degradation of RPV supports from gamma irradiation is improbable or minimal. The findings reported herein were used, in part, as the basis for technical resolution of the issue.

Johnson, R.E. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Engineering Technology; Lipinski, R.E. [Idaho National Engineering Lab., Rockville, MD (United States)

1996-05-01T23:59:59.000Z

470

Chapter 9 - Vacuum and High-Pressure Distillation  

Science Journals Connector (OSTI)

Abstract In industrial practice, multistage distillation operations are carried out over a wide range of operating pressures, from about 0.1 to 40 bar (10,000 to 40·105 Pa). Major factors in choosing the operating pressure are the temperatures of the available cooling and heating media, with water and low-pressure steam being the most convenient ones. Volatile materials require high pressure to raise their condensation temperature to the desired level. Relative volatility tends to decrease with increasing pressure, and, thermodynamically, the upper limit is the critical temperature of the components in the feed. In such cases, a lower operating pressure is chosen and refrigeration must be employed for condensation of overhead vapor instead of cooling water or air. When dealing with high-boiling material, the upper limit for setting the operating pressure depends on the heat sensitivity of the bottom product components. This often requires distilling under an appropriate vacuum in conjunction with a low enough pressure drop to reduce the column bottom temperature accordingly. From the column design point of view, the operating pressure dictates to a great extent the choice and design of internals, and it influences significantly their functionality and overall performance. The main objective of the present chapter is to address and discuss operating pressure selection criteria as well as pressure effects on stage and reflux requirement, vapor and liquid properties, distillation process in general, and trayed and packed-column hydraulics and efficiency in particular.

Žarko Oluji?

2014-01-01T23:59:59.000Z

471

Low-Pressure Sodium Lighting Basics | Department of Energy  

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

Low-Pressure Sodium Lighting Basics Low-Pressure Sodium Lighting Basics Low-Pressure Sodium Lighting Basics August 16, 2013 - 10:17am Addthis Low-pressure sodium lighting provides more energy-efficient outdoor lighting than high-intensity discharge lighting, but it has very poor color rendition. Typical applications include highway and security lighting, where color is not important. Low-pressure sodium lamps work somewhat like fluorescent lamps. Like high-intensity discharge lighting, low-pressure sodium lamps require up to 10 minutes to start and have to cool before they can restart. Therefore, they are most suitable for applications in which they stay on for hours at a time. They are not suitable for use with motion detectors. The chart below compares low-pressure sodium lamps and high-intensity

472

Low pressure cooling seal system for a gas turbine engine  

DOE Patents (OSTI)

A low pressure cooling system for a turbine engine for directing cooling fluids at low pressure, such as at ambient pressure, through at least one cooling fluid supply channel and into a cooling fluid mixing chamber positioned immediately downstream from a row of turbine blades extending radially outward from a rotor assembly to prevent ingestion of hot gases into internal aspects of the rotor assembly. The low pressure cooling system may also include at least one bleed channel that may extend through the rotor assembly and exhaust cooling fluids into the cooling fluid mixing chamber to seal a gap between rotational turbine blades and a downstream, stationary turbine component. Use of ambient pressure cooling fluids by the low pressure cooling system results in tremendous efficiencies by eliminating the need for pressurized cooling fluids for sealing this gap.

Marra, John J

2014-04-01T23:59:59.000Z

473

Version pressure feedback mechanisms for speculative versioning caches  

DOE Patents (OSTI)

Mechanisms are provided for controlling version pressure on a speculative versioning cache. Raw version pressure data is collected based on one or more threads accessing cache lines of the speculative versioning cache. One or more statistical measures of version pressure are generated based on the collected raw version pressure data. A determination is made as to whether one or more modifications to an operation of a data processing system are to be performed based on the one or more statistical measures of version pressure, the one or more modifications affecting version pressure exerted on the speculative versioning cache. An operation of the data processing system is modified based on the one or more determined modifications, in response to a determination that one or more modifications to the operation of the data processing system are to be performed, to affect the version pressure exerted on the speculative versioning cache.

Eichenberger, Alexandre E.; Gara, Alan; O'Brien, Kathryn M.; Ohmacht, Martin; Zhuang, Xiaotong

2013-03-12T23:59:59.000Z

474

Contribution of water vapor pressure to pressurization of plutonium dioxide storage containers  

Science Journals Connector (OSTI)

Pressurization of long-term storage containers filled with materials meeting the US DOE storage standard is of concern.1 2 For example temperatures within storage containers packaged according to the standard and contained in 9975 shipping packages that are stored in full view of the sun can reach internal temperatures of 250?°C.3 Twenty five grams of water (0.5 wt.%) at 250?°C in the storage container with no other material present would result in a pressure of 412 psia which is limited by the amount of water. The pressure due to the water can be substantially reduced due to interactions with the stored material. Studies of the adsorption of water by PuO 2 and surface interactions of water with PuO 2 show that adsorption of 0.5 wt.% of water is feasible under many conditions and probable under high humidity conditions.4 5 6 However no data are available on the vapor pressure of water over plutonium dioxide containing materials that have been exposed to water.

D. Kirk Veirs; John S. Morris; Dane R. Spearing

2000-01-01T23:59:59.000Z

475

Capillary pressure and wettability behavior of CO{sub 2} sequestration in coal at elevated pressures  

SciTech Connect

Enhanced coalbed-methane (ECBM) recovery combines recovery of methane (CH{sub 4}) from coal seams with storage of carbon dioxide (CO{sub 2}). The efficiency of ECBM recovery depends on the CO{sub 2} transfer rate between the macrocleats, via the microcleats to the coal matrix. Diffusive transport of CO{sub 2} in the small cleats is enhanced when the coal is CO{sub 2}-wet. Indeed, for water-wet conditions, the small fracture system is filled with water and the rate of CO{sub 2} sorption and CH{sub 4} desorption is affected by slow diffusion of CO{sub 2}. This work investigates the wetting behavior of coal using capillary pressures between CO{sub 2} and water, measured continuously as a function of water saturation at in-situ conditions. To facilitate the interpretation of the coal measurements, we also obtain capillary pressure curves for unconsolidated-sand samples. For medium- and high-rank coal, the primary drainage capillary pressure curves show a water-wet behavior. Secondary forced-imbibition experiments show that the medium-rank coal becomes CO{sub 2}-wet as the CO{sub 2} pressure increases. High-rank coal is CO{sub 2}-wet during primary imbibition. The imbibition behavior is in agreement with contact-angle measurements. Hence, we conclude that imbibition tests provide the practically relevant data to evaluate the wetting properties of coal.

Plug, W.J.; Mazumder, S.; Bruining, J. [Horizon Energy Partners BV, Hague (Netherlands)

2008-12-15T23:59:59.000Z

476

E-Print Network 3.0 - ambient pressure estimation Sample Search...  

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

at ambient pressure. That is confirmed from the transition temperature TN vs pressure phase... was observed at ambient pressure 6. Along with the data indicating relatively...

477

E-Print Network 3.0 - atmospheric pressure interface Sample Search...  

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

dynamically induced horizontal static pressure gradients at the surface-atmosphere interface (Waddington et al... role of pressure pumping due to atmospheric pressure...

478

ADDITIONAL STRESS AND FRACTURE MECHANICS ANALYSES OF PRESSURIZED WATER REACTOR PRESSURE VESSEL NOZZLES  

SciTech Connect

In past years, the authors have undertaken various studies of nozzles in both boiling water reactors (BWRs) and pressurized water reactors (PWRs) located in the reactor pressure vessel (RPV) adjacent to the core beltline region. Those studies described stress and fracture mechanics analyses performed to assess various RPV nozzle geometries, which were selected based on their proximity to the core beltline region, i.e., those nozzle configurations that are located close enough to the core region such that they may receive sufficient fluence prior to end-of-life (EOL) to require evaluation of embrittlement as part of the RPV analyses associated with pressure-temperature (P-T) limits. In this paper, additional stress and fracture analyses are summarized that were performed for additional PWR nozzles with the following objectives: To expand the population of PWR nozzle configurations evaluated, which was limited in the previous work to just two nozzles (one inlet and one outlet nozzle). To model and understand differences in stress results obtained for an internal pressure load case using a two-dimensional (2-D) axi-symmetric finite element model (FEM) vs. a three-dimensional (3-D) FEM for these PWR nozzles. In particular, the ovalization (stress concentration) effect of two intersecting cylinders, which is typical of RPV nozzle configurations, was investigated. To investigate the applicability of previously recommended linear elastic fracture mechanics (LEFM) hand solutions for calculating the Mode I stress intensity factor for a postulated nozzle corner crack for pressure loading for these PWR nozzles. These analyses were performed to further expand earlier work completed to support potential revision and refinement of Title 10 to the U.S. Code of Federal Regulations (CFR), Part 50, Appendix G, Fracture Toughness Requirements, and are intended to supplement similar evaluation of nozzles presented at the 2008, 2009, and 2011 Pressure Vessels and Piping (PVP) Conferences. This work is also relevant to the ongoing efforts of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code, Section XI, Working Group on Operating Plant Criteria (WGOPC) efforts to incorporate nozzle fracture mechanics solutions into a revision to ASME B&PV Code, Section XI, Nonmandatory Appendix G.

Walter, Matthew [Structural Integrity Associates, Inc.; Yin, Shengjun [ORNL; Stevens, Gary [U.S. Nuclear Regulatory Commission; Sommerville, Daniel [Structural Integrity Associates, Inc.; Palm, Nathan [Westinghouse Electric Company, Cranberry Township, PA; Heinecke, Carol [Westinghouse Electric Company, Cranberry Township, PA

2012-01-01T23:59:59.000Z

479

What measures climate? A variety of variables including their variability and extreme values determine climate for  

E-Print Network (OSTI)

climate zones? The sun is the ultimate power source for the climate "machine". The uneven distribution conditions. Typical variables to consider are temperature (maximum, miniumum), precipitation (includes rain, sleet, snow, hail, etc), sunlight/cloudiness, wind, humidity, ice cover, sea temperature, etc... Many

Allan, Richard P.

480

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

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.


481

Variable-field permanent magnet dipole  

SciTech Connect

A new concept for a variable-field permanent-magnet dipole (VFPMD) has been designed, fabricated, and tested at Los Alamos. The VFPMD is a C-shaped sector magnet with iron poles separated by a large block of magnet material (SmCo). The central field can be continuously varied from 0.07 T to 0.3 T by moving an iron shunt closer or further away from the back of the magnet. The shunt is specially shaped to make the dependence of the dipole field strength on the shunt position as linear as possible. The dipole has a 2.8 cm high by 8 cm wide aperture with {approximately}10 cm long poles.

Barlow, D.B.; Kraus, R.H. Jr.; Meyer, R.E.

1993-10-01T23:59:59.000Z

482

Dissecting magnetar variability with Bayesian hierarchical models  

E-Print Network (OSTI)

Neutron stars are a prime laboratory for testing physical processes under conditions of strong gravity, high density, and extreme magnetic fields. Among the zoo of neutron star phenomena, magnetars stand out for their bursting behaviour, ranging from extremely bright, rare giant flares to numerous, less energetic recurrent bursts. The exact trigger and emission mechanisms for these bursts are not known; favoured models involve either a crust fracture and subsequent energy release into the magnetosphere, or explosive reconnection of magnetic field lines. In the absence of a predictive model, understanding the physical processes responsible for magnetar burst variability is difficult. Here, we develop an empirical model that decomposes magnetar bursts into a superposition of small spike-like features with a simple functional form, where the number of model components is itself part of the inference problem. The cascades of spikes that we model might be formed by avalanches of reconnection, or crust rupture afte...

Huppenkothen, D; Hogg, D W; Murray, I; Frean, M; Elenbaas, C; Watts, A L; Levin, Y; van der Horst, A J; Kouveliotou, C

2015-01-01T23:59:59.000Z

483

Improvements of the Variable Thermal Resistance  

E-Print Network (OSTI)

A flat mounting unit with electronically variable thermal resistance [1] has been presented in the last year [2]. The design was based on a Peltier cell and the appropriate control electronics and software. The device is devoted especially to the thermal characterization of packages, e.g. in dual cold plate arrangements. Although this design meets the requirements of the static measurement we are intended to improve its parameters as the settling time and dynamic thermal impedance and the range of realized thermal resistance. The new design applies the heat flux sensor developed by our team as well [3], making easier the control of the device. This development allows even the realization of negative thermal resistances.

V. Szekely; S. Torok; E. Kollar

2008-01-07T23:59:59.000Z

484

Dark matter interacts with variable vacuum energy  

E-Print Network (OSTI)

We investigate a spatially flat Friedmann-Robertson-Walker (FRW) scenario with two interacting components, dark matter and variable vacuum energy (VVE) densities, plus two decoupled components, one is a baryon term while the other behaves as a radiation component. We consider a linear interaction in the derivative dark component density. We apply the $\\chi^2$ method to the observational Hubble data for constraining the cosmological parameters and analyze the amount of dark energy in the radiation era for the model. It turns out that our model fulfills the severe bound of $\\Omega_{x}(z\\simeq 1100)survey, the future constraints achievable by Euclid and CMBPol experiments, reported for the behavior of the dark energy at early times, and fulfills the stringent bound $\\Omega_{x}(z\\simeq 10^{10})<0.04$ at $2\\sigma$ level in the big-bang nucleosynthesis epoch. We a...

G, Iván E Sánchez

2014-01-01T23:59:59.000Z

485

Acoustic cavitation and its chemical consequences  

Science Journals Connector (OSTI)

...addition of gaseous hydrocarbons (methane, ethylene...in water and of C2 in hydrocarbons), SBSL is an essentially...diffraction peak; after heat treatment under helium...neutron-diffraction data confirmed these measurements...fossil fuels before combustion (Gates 1992). We...

1999-01-01T23:59:59.000Z

486

Acoustic cavitation and its chemical consequences  

Science Journals Connector (OSTI)

...homogeneous' sonochemistry nanophase inorg. mat. water remediation ground water catalysts magnetic materials liquid-solid with...sonoluminescence Sonoluminescence was first observed from water by Frenzel & Schultes (1934). As with sonochemistry...

1999-01-01T23:59:59.000Z

487

Building Technologies Office: Advanced, Variable Speed Air-Source  

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

Advanced, Variable Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project to someone by E-mail Share Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Facebook Tweet about Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Twitter Bookmark Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Google Bookmark Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Delicious Rank Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Digg Find More places to share Building Technologies Office: Advanced,

488

Tritium issues in commercial pressurized water reactors  

SciTech Connect

Tritium has become an important radionuclide in commercial Pressurized Water Reactors because of its mobility and tendency to concentrate in plant systems as tritiated water during the recycling of reactor coolant. Small quantities of tritium are released in routine regulated effluents as liquid water and as water vapor. Tritium has become a focus of attention at commercial nuclear power plants in recent years due to inadvertent, low-level, chronic releases arising from routine maintenance operations and from component failures. Tritium has been observed in groundwater in the vicinity of stations. The nuclear industry has undertaken strong proactive corrective measures to prevent recurrence, and continues to eliminate emission sources through its singular focus on public safety and environmental stewardship. This paper will discuss: production mechanisms for tritium, transport mechanisms from the reactor through plant, systems to the environment, examples of routine effluent releases, offsite doses, basic groundwater transport and geological issues, and recent nuclear industry environmental and legal ramifications. (authors)

Jones, G. [Constellation Energy Group, R.E. Ginna Nuclear Power Plant, Ontario, NY (United States)

2008-07-15T23:59:59.000Z

489

Hybrid air foil bearing with external pressurization  

E-Print Network (OSTI)

) becomes smooth. 20 Figure 3.7 Non-dimensional film thickness for operating parameters in Table 3.1 with S f =1 21 m ? m ? (a) S f = 0.8 m ? (b) S f = 0.5 (c) S f = 0.2 m ? Figure 3... and NASA [18] experimental minimum film thickness; L/D=1, C=31.8 m? , and bump stiffness = 4.7 GN/m 3 Figure 3.11 describes a non-dimensional pressure (P=p/p a ), film thickness (H=h/C), and bump deflection (W=w B /C) for the bearing in Table 3.1 at 45...

Park, Soongook

2009-05-15T23:59:59.000Z

490

Propagation of an atmospheric pressure plasma plume  

SciTech Connect

The ''plasma bullet'' behavior of atmospheric pressure plasma plumes has recently attracted significant interest. In this paper, a specially designed plasma jet device is used to study this phenomenon. It is found that a helium primary plasma can propagate through the wall of a dielectric tube and keep propagating inside the dielectric tube (secondary plasma). High-speed photographs show that the primary plasma disappears before the secondary plasma starts to propagate. Both plumes propagate at a hypersonic speed. Detailed studies on the dynamics of the plasma plumes show that the local electric field induced by the charges on the surface of the dielectric tube plays an important role in the ignition of the secondary plasma. This indicates that the propagation of the plasma plumes may be attributed to the local electric field induced by the charges in the bulletlike plasma volume.

Lu, X.; Xiong, Q.; Xiong, Z.; Hu, J.; Zhou, F.; Gong, W.; Xian, Y.; Zou, C.; Tang, Z.; Jiang, Z.; Pan, Y. [College of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)

2009-02-15T23:59:59.000Z

491

Pressure equalizing photovoltaic assembly and method  

DOE Patents (OSTI)

Each PV assembly of an array of PV assemblies comprises a base, a PV module and a support assembly securing the PV module to a position overlying the upper surface of the base. Vents are formed through the base. A pressure equalization path extends from the outer surface of the PV module, past the peripheral edge of the PV module, to and through at least one of the vents, and to the lower surface of the base to help reduce wind uplift forces on the PV assembly. The PV assemblies may be interengaged, such as by interengaging the bases of adjacent PV assemblies. The base may include a main portion and a cover and the bases of adjacent PV assemblies may be interengaged by securing the covers of adjacent bases together.

Dinwoodie, Thomas L. (Piedmont, CA)

2003-05-27T23:59:59.000Z

492

Propagation of light in low pressure gas  

E-Print Network (OSTI)

The criticism by W. E. Lamb, W. Schleich, M. Scully, C. Townes of a simplified quantum electrodynamics which represents the photon as a true particle is illustrated. Collisions being absent in low-pressure gas, exchanges of energy are radiative and coherent. Thin shells of plasma containing atoms in a model introduced by Str\\"omgren are superradiant, seen as circles possibly dotted. Spectral radiance of novae has magnitude of laser radiance, and column densities are large in nebulae: Superradiance, multiphoton effects, etc., work in astrophysics. The superradiant beams induce multiphotonic scatterings of light emitted by the stars, brightening the limbs of plasma bubbles and darkening the stars. In excited atomic hydrogen, impulsive Raman scatterings shift frequencies of light. Microwaves exchanged with the Pioneer probes are blueshifted, simulating anomalous accelerations. Substituting coherence for wrong calculations in astrophysical papers, improves results, avoids "new physics".

Jacques Moret-Bailly

2012-04-13T23:59:59.000Z

493

Chemistry of nitromethane at very high pressure  

SciTech Connect

Decomposition of nitromethane is reported over the range of 115- 180/degree/C and 0.6-8.5 GPa. About 5 /mu/g of nitromethane is compressed with a diamond-anvil cell, heated to the point that reaction occurs, and held typically 10-20 minutes at the reaction temperature. The cell is cooled and the volatile contents of the cell are frozen as a thin layer in vacuo and an infrared absorption spectrum is recorded. The three volatile products observed are N/sub 2/O, CO/sub 2/, and water, with N/sub 2/O production peaking at 1.5 GPa, 135/degree/C, and 35% of NME; CO/sub 2/ production peaking at 3.5 GPa, 135/degree/C, and 65% of NME, and water yields at 20-50% of NME at the highest pressure measured, 8.5 GPa and 175/degree/C. Water yields were difficult to quantify due to background contamination. Results indicate three different reactions for solid NME dependent primarily on the pressure of the reaction, and that fluid NME does not decompose at 0.6 GPa and 175/degree/C, although the solid decomposes readily at 1.1 GPa and 120/degree/C. The authors conclude that, while various decomposition mechanisms are possible, the initial step CH/sub 3/NO/sub 2/ /yields/ /center dot/CH/sub 3/ + /center dot/NO/sub 2/ is very unlikely. 14 refs., 5 figs.

Agnew, S.F.; Swanson, B.I.; Kenney, J.; Kenney, I.

1989-01-01T23:59:59.000Z

494

High-pressure coal fuel processor development  

SciTech Connect

Caterpillar shares DOE/METC interest in demonstrating the technology required to displace petroleum-based engine fuels with various forms of low cost coal. Current DOE/METC programs on mild gasification and coal-water-slurries are addressing two approaches to this end. Engine and fuel processor system concept studies by Caterpillar have identified a third, potentially promising, option. This option includes high-pressure fuel processing of run-of-the-mine coal and direct injection of the resulting low-Btu gas stream into an ignition assisted, high compression ratio diesel engine. The compactness and predicted efficiency of the system make it suitable for application to line-haul railroad locomotives. Two overall conclusions resulted from Task 1. First direct injected, ignition assisted Diesel cycle engine combustion systems can be suitably modified to efficiently utilize low-Btu gas fuels. Second, high pressure gasification of selected run-of-the-mine coals in batch-loaded fuel processors is feasible. These two findings, taken together, significantly reduce the perceived technical risk associated with the further development of the proposed coal gas fueled Diesel cycle power plant concept. The significant conclusions from Task 2 were: An engine concept, derived from a Caterpillar 3600 series engine, and a fuel processor concept, based on scaling up a removable-canister configuration from the test rig, appear feasible; and although the results of this concept study are encouraging, further, full-scale component research and development are required before attempting a full-scale integrated system demonstration effort.

Greenhalgh, M.L. (Caterpillar, Inc., Peoria, IL (United States))

1992-12-01T23:59:59.000Z

495

Natural gas cleanup: Evaluation of a molecular sieve carbon as a pressure swing adsorbent for the separation of methane/nitrogen mixtures  

SciTech Connect

This report describes the results of a preliminary evaluation to determine the technical feasibility of using a molecular sieve carbon manufactured by the Takeda Chemical Company of Japan in a pressure owing adsorption cycle for upgrading natural gas (methane) contaminated with nitrogen. Adsorption tests were conducted using this adsorbent in two, four, and five-step adsorption cycles. Separation performance was evaluated in terms of product purity, product recovery, and sorbent productivity for all tests. The tests were conducted in a small, single-column adsorption apparatus that held 120 grams of the adsorbent. Test variables included adsorption pressure, pressurization rate, purge rate and volume, feed rate, and flow direction in the steps from which the product was collected. Sorbent regeneration was accomplished by purging the column with the feed gas mixture for all but one test series where a pure methane purge was used. The ratio between the volumes of the pressurization gas and the purge gas streams was found to be an important factor in determining separation performance. Flow rates in the various cycle steps had no significant effect. Countercurrent flow in the blow-down and purge steps improved separation performance. Separation performance appears to improve with increasing adsorption pressure, but because there are a number of interrelated variables that are also effected by pressure, further testing will be needed to verify this. The work demonstrates that a molecular sieve carbon can be used to separate a mixture of methane and nitrogen when used in a pressure swing cycle with regeneration by purge. Further work is needed to increase product purity and product recovery.

Grimes, R.W.

1994-06-01T23:59:59.000Z

496

High Temperature Electrolysis Pressurized Experiment Design, Operation, and Results  

SciTech Connect

A new facility has been developed at the Idaho National Laboratory for pressurized testing of solid oxide electrolysis stacks. Pressurized operation is envisioned for large-scale hydrogen production plants, yielding higher overall efficiencies when the hydrogen product is to be delivered at elevated pressure for tank storage or pipelines. Pressurized operation also supports higher mass flow rates of the process gases with smaller components. The test stand can accommodate planar cells with dimensions up to 8.5 cm x 8.5 cm and stacks of up to 25 cells. It is also suitable for testing other cell and stack geometries including tubular cells. The pressure boundary for these tests is a water-cooled spool-piece pressure vessel designed for operation up to 5 MPa. Pressurized operation of a ten-cell internally manifolded solid oxide electrolysis stack has been successfully demonstrated up 1.5 MPa. The stack is internally manifolded and operates in cross-flow with an inverted-U flow pattern. Feed-throughs for gas inlets/outlets, power, and instrumentation are all located in the bottom flange. The entire spool piece, with the exception of the bottom flange, can be lifted to allow access to the internal furnace and test fixture. Lifting is accomplished with a motorized threaded drive mechanism attached to a rigid structural frame. Stack mechanical compression is accomplished using springs that are located inside of the pressure boundary, but outside of the hot zone. Initial stack heatup and performance characterization occurs at ambient pressure followed by lowering and sealing of the pressure vessel and subsequent pressurization. Pressure equalization between the anode and cathode sides of the cells and the stack surroundings is ensured by combining all of the process gases downstream of the stack. Steady pressure is maintained by means of a backpressure regulator and a digital pressure controller. A full description of the pressurized test apparatus is provided in this report. Results of initial testing showed the expected increase in open-cell voltage associated with elevated pressure. However, stack performance in terms of area-specific resistance was enhanced at elevated pressure due to better gas diffusion through the porous electrodes of the cells. Some issues such as cracked cells and seals were encountered during testing. Full resolution of these issues will require additional testing to identify the optimum test configurations and protocols.

J.E. O'Brien; X. Zhang; G.K. Housley; K. DeWall; L. Moore-McAteer

2012-09-01T23:59:59.000Z

497

High-pressure Infrared Spectra of Tal and Lawsonite  

SciTech Connect

We present high-pressure infrared spectra of two geologically important hydrous minerals: talc, Mg3Si4O10(OH)2 and lawsonite, CaAl2Si2O7(OH)2{center_dot}H2O,{center_dot}at room temperature. For lawsonite, our data span the far infrared region from 150 to 550 cm-1 and extend to 25 GPa. We combine our new spectroscopic data with previously published high-pressure mid-infrared and Raman data to constrain the Gr{umlt u}neisen parameter and vibrational density of states under pressure. In the case of talc, we present high-pressure infrared data that span both the mid and far infrared from 150 to 3800 cm-1 covering lattice, silicate, and hydroxyl stretching vibrations to a maximum pressure of 30 GPa. Both phases show remarkable metastability well beyond their nominal maximum thermodynamic stability at simultaneous high-pressure and high-temperature conditions.

Scott,H.; Liu, Z.; Hemley, R.; Williams, Q.

2007-01-01T23:59:59.000Z

498

SLUDGE BATCH 7B GLASS VARIABILITY STUDY  

SciTech Connect

The Defense Waste Processing Facility (DWPF) is preparing to initiate processing Sludge Batch 7b (SB7b). In support of the upcoming processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frits 418 with a 6% Na{sub 2}O addition (26 wt% Na{sub 2}O in sludge) and 702 with a 4% Na{sub 2}O addition (24 wt% Na{sub 2}O in sludge) to process SB7b. This recommendation was based on assessments of the compositional projections for SB7b available at the time from the Savannah River Remediation (SRR). To support qualification of SB7b, SRNL executed a variability study to assess the applicability of the current durability models for SB7b. The durability models were assessed over the expected composition range of SB7b, including potential caustic additions, combined with Frits 702 and 418 over a 32-40% waste loading (WL) range. Thirty four glasses were selected based on Frits 418 and 702 coupled with the sludge projections with an additional 4-6% Na{sub 2}O to reflect the potential caustic addition. Six of these glasses, based on average nominal sludge compositions including the appropriate caustic addition, were developed for both Frit 418 and Frit 702 at 32, 36 and 40% WL to provide coverage in the center of the anticipated SB7b glass region. All glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). To comply with the DWPF Glass Product Control Program, a total of thirty four glasses were fabricated to assess the applicability of the current DWPF PCCS durability models. Based on the measured PCT response, all of the glasses were acceptable with respect to the Environmental Assessment (EA) benchmark glass regardless of thermal history. The NL[B] values of the SB7b variability study glasses were less than 1.99 g/L as compared to 16.695 g/L for EA. A small number of the D-optimally selected 'outer layer' extreme vertices (EV) glasses were not predictable using the current Product Composition Control System (PCCS) models for durability, but were acceptable compared to the EA glass when tested. These glasses fell outside of the lower 95% confidence band, which demonstrates conservatism in the model. A few of the glasses fell outside of the upper 95% confidence band; however, these particular glasses have normalized release values that were much lower than the values of EA and should be of no practical concern. Per the requirements of the DWPF Glass Product Control Program, the PCCS durability models have been shown to be applicable to the SB7b sludge system with a range of Na{sub 2}O concentrations blended with Frits 418 or 702. PCT results from the glasses fabricated as part of the variability study were shown to be predictable by the current DWPF PCCS models and/or acceptable with respect to the EA benchmark glass regardless of thermal history or compositional view.

Johnson, F.; Edwards, T.

2011-10-25T23:59:59.000Z

499

Pressure gradient passivation of carbonaceous material normally susceptible to spontaneous combustion  

DOE Patents (OSTI)

This invention is a process for the passivation or deactivation with respect to oxygen of a carbonaceous material by the exposure of the carbonaceous material to an oxygenated gas in which the oxygenated gas pressure is increased from a first pressure to a second pressure and then the pressure is changed to a third pressure. Preferably a cyclic process which comprises exposing the carbonaceous material to the gas at low pressure and increasing the pressure to a second higher pressure and then returning the pressure to a lower pressure is used. The cycle is repeated at least twice wherein the higher pressure may be increased after a selected number of cycles.

Ochs, Thomas L.; Sands, William D.; Schroeder, Karl; Summers, Cathy A.; Utz, Bruce R.

2002-01-29T23:59:59.000Z

500

Soot particle sizing during high-pressure Diesel spray combustion via time-resolved laser-induced incandescence  

SciTech Connect

Single-pulse time-resolved laser-induced incandescence (TiRe-LII) signal transients from soot particulates were acquired during unsteady high pressure Diesel combustion in a constant volume cell for typical top dead center conditions during a Diesel engine cycle. Measurements were performed for initial gas pressures between 1 and 3 MPa, injection pressures between 50 and 130 MPa and laser probe timings between 5 and 16 ms after start of fuel injection. In separate experiments and for the same cell operating conditions gas temperatures were deduced from spectrally resolved soot pyrometry measurements. Implementing the LII model of Kock et al. [Combust. Flame 147 (2006) 79-92] ensemble mean soot particle diameters were evaluated from least-squares fitting of theoretical cooling curves to experimental TiRe-LII signal transients. Since in the experiments the environmental gas temperature and the width of an assumed particle size distribution were not known, the effects of the initial choice of these parameters on retrieved particle diameters were investigated. It is shown that evaluated mean particle diameters are only slightly biased by the choice of typical size distribution widths and gas temperatures. For a fixed combustion phase mean particle diameters are not much affected by gas pressure, however they become smaller at high fuel injection pressure. At a mean chamber pressure of 1.39 MPa evaluated mean particle diameters increased by a factor of two for probe delays between 5 and 16 ms after start of injection irrespective of the choices of first-guess fitting variables, indicating a certain robustness of data analysis procedure. (author)

Ryser, R.; Gerber, T.; Dreier, T. [Reaction Analysis Group, Department of General Energy, Paul Scherrer Institute, CH-5232 Villigen PSI (Switzerland)

2008-11-15T23:59:59.000Z