Sample records for radiographic hydrodynamic test

  1. Dual Axis Radiographic Hydrodynamic Test Facility | National...

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

    Dual Axis Radiographic Hydrodynamic Test Facility | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing...

  2. EIS-0228: Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility

    Broader source: Energy.gov [DOE]

    This EIS evaluates the potential environmental impact of a proposal to construct and operate the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory (LANL)...

  3. Dual Axis Radiographic Hydrodynamic Test Facility mitigation action plan. Annual report for 1998

    SciTech Connect (OSTI)

    Haagenstad, T.

    1999-01-15T23:59:59.000Z

    This Mitigation Action Plan Annual Report (MAPAR) has been prepared as part of implementing the Dual Axis Radiographic Hydrodynamic Test Facility (DARHT) Mitigation Action Plan (MAP) to protect workers, soils, water, and biotic and cultural resources in and around the facility.

  4. Dual axis radiographic hydrodynamic test facility. Final environmental impact statement, Volume 2: Public comments and responses

    SciTech Connect (OSTI)

    NONE

    1995-08-01T23:59:59.000Z

    On May 12, 1995, the U.S. Department of Energy (DOE) issued the draft Dual Axis Radiographic Hydrodynamic Test Facility Environmental Impact Statement (DARHT EIS) for review by the State of New Mexico, Indian Tribes, local governments, other Federal agencies, and the general public. DOE invited comments on the accuracy and adequacy of the draft EIS and any other matters pertaining to their environmental reviews. The formal comment period ran for 45 days, to June 26, 1995, although DOE indicated that late comments would be considered to the extent possible. As part of the public comment process, DOE held two public hearings in Los Alamos and Santa Fe, New Mexico, on May 31 and June 1, 1995. In addition, DOE made the draft classified supplement to the DARHT EIS available for review by appropriately cleared individuals with a need to know the classified information. Reviewers of the classified material included the State of New Mexico, the U.S. Environmental Protection Agency, the Department of Defense, and certain Indian Tribes. Volume 2 of the final DARHT EIS contains three chapters. Chapter 1 includes a collective summary of the comments received and DOE`s response. Chapter 2 contains the full text of the public comments on the draft DARHT EIS received by DOE. Chapter 3 contains DOE`s responses to the public comments and an indication as to how the comments were considered in the final EIS.

  5. Dual Axis Radiographic Hydrodynamic Test Facility mitigation action plan. Annual report for 1997

    SciTech Connect (OSTI)

    Haagenstad, H.T.

    1998-01-15T23:59:59.000Z

    This Mitigation Action Plan Annual Report (MAPAR) has been prepared by the US Department of Energy (DOE) as part of implementing the Dual Axis Radiographic Hydrodynamic Test Facility (DARHT) Mitigation Action Plan (MAP). This MAPAR provides a status on specific DARHT facility design- and construction-related mitigation actions that have been initiated in order to fulfill DOE`s commitments under the DARHT MAP. The functions of the DARHT MAP are to (1) document potentially adverse environmental impacts of the Phased Containment Option delineated in the Final EIS, (2) identify commitments made in the Final EIS and ROD to mitigate those potential impacts, and (3) establish Action Plans to carry out each commitment (DOE 1996). The DARHT MAP is divided into eight sections. Sections 1--5 provide background information regarding the NEPA review of the DARHT project and an introduction to the associated MAP. Section 6 references the Mitigation Action Summary Table which summaries the potential impacts and mitigation measures; indicates whether the mitigation is design-, construction-, or operational-related; the organization responsible for the mitigation measure; and the projected or actual completion data for each mitigation measure. Sections 7 and 8 discuss the Mitigation Action Plan Annual Report and Tracking System commitment and the Potential Impacts, Commitments, and Action Plans respectively. Under Section 8, potential impacts are categorized into five areas of concern: General Environment, including impacts to air and water; Soils, especially impacts affecting soil loss and contamination; Biotic Resources, especially impacts affecting threatened and endangered species; Cultural/Paleontological Resources, especially impacts affecting the archeological site known as Nake`muu; and Human Health and Safety, especially impacts pertaining to noise and radiation. Each potential impact includes a brief statement of the nature of the impact and its cause(s). The commitment made to mitigate the potential impact is identified and the Action Plan for each commitment is described in detail, with a description of actions to be taken, pertinent time frames for the actions, verification of mitigation activities, and identification of agencies/organizations responsible for satisfying the requirements of the commitment.

  6. Radionuclides in Small Mammals Collected at the Dual-Axis Radiographic Hydrodynamic Test (DARHT) Facility during 2001-- 2003

    SciTech Connect (OSTI)

    P.R. Fresquez

    2005-01-20T23:59:59.000Z

    Rodents are effective indicators of environmental contamination and the Dual-Axis Radiographic Hydrodynamic Test (DARHT) Facility Mitigation Action Plan specifies the (radionuclide) comparison of small mammals to baseline levels to determine if there are any impacts as a result of operations. Consequently, samples of (whole body) field mice (Peromyscus spp.) were collected from within the grounds of the DARHT facility at Los Alamos National Laboratory, Technical Area 15, from 2001 through 2003. Samples were analyzed for {sup 3}H, {sup 137}Cs, {sup 90}Sr, {sup 241}Am, {sup 238}Pu, {sup 239,240}Pu, {sup 234}U, {sup 235}U, and {sup 238}U. Results, which represent three years since the start of operations in 2000, were compared with baseline statistical reference level (BSRL) data established over a four-year-long preoperational period. Most radionuclides in mice were either at nondetectable levels or within BSRLs. The few radionuclides that were above BSRLs included U isotopes; and the ratios of some samples indicated depleted U sources. Although the amounts of U in some samples were just above BSRLs, and since depleted U is less soluble and less toxic (chemical and radioactive) than naturally occurring U, the very small levels in the mice collected around the DARHT facility grounds are unlikely to pose a threat to predators that feed upon them.

  7. axis radiographic hydrodynamic: Topics by E-print Network

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

    For an "empty vacuum" the hydrodynamic equations are familiar ones (shallow water-wave equations) and they describe an experimentally observed phenomenon -- the...

  8. Dual Axis Radiographic Hydrodynamic Test Facility

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMFormsGasRelease Date: Contact:DisclaimersMaterialsTechnologiesDARHT

  9. A proposed benchmark for simulation in radiographic testing

    SciTech Connect (OSTI)

    Jaenisch, G.-R.; Deresch, A.; Bellon, C. [Federal Institute for Materials Research and Testing Unter den Eichen 87, 12205 Berlin (Germany); Schumm, A.; Guerin, P. [EDF R and D, 1 avenue du Général de Gaulle, 92141 Clamart (France)

    2014-02-18T23:59:59.000Z

    The purpose of this benchmark study is to compare simulation results predicted by various models of radiographic testing, in particular those that are capable of separately predicting primary and scatter radiation for specimens of arbitrary geometry.

  10. A benchmark concept for simulation in radiographic testing

    SciTech Connect (OSTI)

    Ewert, U.; Deresch, A.; Bellon, C.; Jaenisch, G.-R. [Federal Institute for Materials Research and Testing Unter den Eichen 87, 12205 Berlin (Germany)

    2014-02-18T23:59:59.000Z

    The new standard ISO 17636–2:2013 “NDT of welds: Radiographic testing - Part 2: X- and gamma ray techniques with digital detectors” describes a complex procedure for film replacement by phosphor imaging plates and digital detector arrays. RT modeling software should consider these detector types, X-ray film, and the standard requirements for image quality. Practitioners expect the same visibility of image quality indicators (IQI) in the simulated radiographs as in the experimental exposures. The proposed benchmark test is based on the comparison of experimental radiographs taken at BAM with modeled ones of participants. The experimental setup and the determination of the equivalent penetrameter sensitivity (EPS) as described in the procedure of ASTM E 746 are used for quantitative evaluation of the achievable contrast sensitivity for step hole IQIs as considered in Annex B of ISO 17636–2. System classification data for Computed Radiography (CR) and film systems will be provided by BAM according to ISO 11699–1 for selected film systems and according to ASTM E 2446 for selected CR systems. The classification of films and digital detectors is based on the measurement of the dose response function, the basic spatial resolution (SR{sub b}) of the image, and the measured image noise, which depends on the detector efficiency, the quantum statistics, and the detector fixed pattern noise.

  11. DARHT: Dual-Axis Radiographic Hydrodynamic Test Facility

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

    to analyze mockups of nuclear weapons. The DARHT Facility DARHT consists of two linear induction accelerators that are oriented at two right angles to one another. Each electron...

  12. Dual Axis Radiographic Hydrodynamic Test Facility | National Nuclear

    National Nuclear Security Administration (NNSA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOn AprilA groupTubahq.na.gov Office ofDepartment of EnergyAdministrationSecurity

  13. DARHT: Dual-Axis Radiographic Hydrodynamic Test Facility

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would likeConstitution4Customer-Comments Sign InFuture scientistsDANCEDARHT:

  14. Hydrodynamic Tesla Wheel Flume for Model and Prototype Testing

    E-Print Network [OSTI]

    Wood, Stephen L.

    The Tesla turbine, U.S. Patent 1,061,206 -- May 6, 1913 was invented by Nikola Tesla as a means to extractHydrodynamic Tesla Wheel Flume for Model and Prototype Testing Spencer Jenkins, Chris Scott, Jacob Engineering department at Florida Institute of Technology (Florida Tech) has developed a Hydrodynamic Tesla

  15. Nondestructive Evaluation Quality Procedure: Personnel Qualification and Certification Radiographic Testing-Levels I& II

    SciTech Connect (OSTI)

    Dolan, K; Rikard, R D; Rodriquez, J

    2003-07-01T23:59:59.000Z

    This Operational Procedure establishes the minimum requirements for the qualification and certification/recertification of Nondestructive Evaluation (NDE) personnel in the nondestructive testing (NDT) radiographic testing (RT) method. This document is in accordance with the American Society for Nondestructive Testing Recommended Practice SNT-TC-1A, 1996, except as amended herein.

  16. Tests of the hydrodynamic equivalence of direct-drive implosions with different D2 and 3

    E-Print Network [OSTI]

    Tests of the hydrodynamic equivalence of direct-drive implosions with different D2 and 3 He, D2 and 3 He gases are fully ionized, and hydrodynamically equivalent fuels with different ratios the materials are cho- sen to be as nearly hydrodynamically equivalent as possible. D and 3 He have the special

  17. New requirements for digital radiographic testing of welds according to ISO standards

    SciTech Connect (OSTI)

    Zscherpel, U.; Ewert, U.; Jechow, M. [BAM Federal Institute for Materials Research and Testing, D-12200 Berlin (Germany)

    2013-01-25T23:59:59.000Z

    Users of EN 14784-2 (general principles for computed radiography with phosphor imaging plates) reported about difficulties to achieve testing class B in weld testing with imaging plates. One of the reasons is the insufficient consideration of the inherent detector unsharpness (u{sub i}) in the minimum requirements. Digital detectors have a higher inherent unsharpness compared to film, which can even exceed the geometrical unsharpness (u{sub g}) of the typical contact technique. In EN 444 and ISO 5579 (general principles for film radiography) u{sub i} is neglected for the calculation of the minimum source-to-object distance (SOD), because it is small compared to the geometric unsharpness (u{sub g}). Considering u{sub i} for digital detectors results in a new equation for SOD (see ISO/FDIS 17636-2). Therefore, the increase in total image unsharpness requires the compensation by a larger SOD to reduce u{sub g}. This contribution discusses the need for change of the SOD for different setups (detectors, focal spots, etc.) and explains the difference in image quality, achieved on basis of the extended equation of ISO/FDIS 17636-2. Furthermore, the detection of image quality indicators depends on the achieved Contrast-to-Noise ratio (CNR) and total image unsharpness. Both of them are essential parameters, which influence the contrast sensitivity. Additionally, new compensation principles (e.g. compensation of missing spatial resolution by enhanced contrast sensitivity) allow to widen the application range of digital detectors for radiographic weld testing.

  18. Dual-Axis Radiographic Hydrodynamic Test Facility At the Los Alamos National Laboratory (LANL), the Dual-Axis

    E-Print Network [OSTI]

    's primary mission: to ensure the safety, security, and effectiveness of nuclear weapons in our na- tion of nuclear weapons. The DARHT Facility DARHT consists of two linear induction accelerators that are oriented for computer codes. These radio- graphic images are used to evaluate nuclear weapons though nonnuclear

  19. Stellar hydrodynamical modeling of dwarf galaxies: simulation methodology, tests, and first results

    E-Print Network [OSTI]

    Vorobyov, Eduard I; Hensler, Gerhard

    2015-01-01T23:59:59.000Z

    Cosmological simulations still lack numerical resolution or physical processes to simulate dwarf galaxies in sufficient details. Accurate numerical simulations of individual dwarf galaxies are thus still in demand. We aim at (i) studying in detail the coupling between stars and gas in a galaxy, exploiting the so-called stellar hydrodynamical approach, and (ii) studying the chemo-dynamical evolution of individual galaxies starting from self-consistently calculated initial gas distributions. We present a novel chemo-dynamical code in which the dynamics of gas is computed using the usual hydrodynamics equations, while the dynamics of stars is described by the stellar hydrodynamics approach, which solves for the first three moments of the collisionless Boltzmann equation. The feedback from stellar winds and dying stars is followed in detail. In particular, a novel and detailed approach has been developed to trace the aging of various stellar populations, which enables an accurate calculation of the stellar feedba...

  20. Annual Report: Hydrodynamics and Radiative Hydrodynamics with Astrophysical Applications

    SciTech Connect (OSTI)

    R. Paul Drake

    2005-12-01T23:59:59.000Z

    We report the ongoing work of our group in hydrodynamics and radiative hydrodynamics with astrophysical applications. During the period of the existing grant, we have carried out two types of experiments at the Omega laser. One set of experiments has studied radiatively collapsing shocks, obtaining high-quality scaling data using a backlit pinhole and obtaining the first (ever, anywhere) Thomson-scattering data from a radiative shock. Other experiments have studied the deeply nonlinear development of the Rayleigh-Taylor (RT) instability from complex initial conditions, obtaining the first (ever, anywhere) dual-axis radiographic data using backlit pinholes and ungated detectors. All these experiments have applications to astrophysics, discussed in the corresponding papers either in print or in preparation. We also have obtained preliminary radiographs of experimental targets using our x-ray source. The targets for the experiments have been assembled at Michigan, where we also prepare many of the simple components. The above activities, in addition to a variety of data analysis and design projects, provide good experience for graduate and undergraduates students. In the process of doing this research we have built a research group that uses such work to train junior scientists.

  1. Hydrodynamic/kinetic reactions in liquid dominated geothermal systems: Hydroscale Test Program, Mercer 2 well site South Brawley, California (Tests No. 15--20). Final report, 27 October 1980--6 February 1981

    SciTech Connect (OSTI)

    Nesewich, J.P.; Gracey, C.M. [Los Alamos National Lab., NM (United States)

    1982-04-01T23:59:59.000Z

    The Aerojet Energy Conversion Company, under contract to the Los Alamos National Laboratory, US Department of Energy, has constructed and tested a mobile geothermal well-site test unit at the Mercer 2 well in South Brawley, California (Imperial Valley). The equipment controlled, monitored, and recorded all process conditions of single- and dual-flash power cycles. Single- and two-phase flashed brine effluents were flowed through piping component test sections to provide hydrodynamic/kinetic data for scale formation. The unit operated at flowrates in excess of 200 gpm and is designed to accommodate flowrates up to 300 gpm. Primary scale formations encountered were those of Pbs, Fe{sub 2} (OH){sub 3}Cl (iron hydroxychloride), iron chlorides, and non-crystalline forms Of SiO{sub 2}. The formation of iron hydroxychloride was due to the unusually high concentration of iron in the wellhead brine (5000 mg/1).

  2. Hydrodynamic compressibility of high-strength ceramics

    SciTech Connect (OSTI)

    Grady, D.E.

    1993-08-01T23:59:59.000Z

    In this study we have developed the techniques to investigate the hydrodynamic response of high-strength ceramics by mixing these powders with copper powder, preparing compacts, and performing shock compression tests on these mixtures. Hydrodynamics properties of silicon carbide, titanium diboride, and boron carbide to 30 GPa were examined by this method, and hydrodynamic compression data for these ceramics have been determined. We have concluded, however, that the measurement method is sensitive to sample preparation and uncertainties in shock wave measurements. Application of the experimental technique is difficult and further efforts are needed.

  3. Hydrodynamics of vegetated channels

    E-Print Network [OSTI]

    Nepf, Heidi

    This paper highlights some recent trends in vegetation hydrodynamics, focusing on conditions within channels and spanning spatial scales from individual blades, to canopies or vegetation patches, to the channel reach. At ...

  4. Ionizing Radiation in Smoothed Particle Hydrodynamics

    E-Print Network [OSTI]

    O. Kessel-Deynet; A. Burkert

    2000-02-11T23:59:59.000Z

    A new method for the inclusion of ionizing radiation from uniform radiation fields into 3D Smoothed Particle Hydrodynamics (SPHI) simulations is presented. We calculate the optical depth for the Lyman continuum radiation from the source towards the SPHI particles by ray-tracing integration. The time-dependent ionization rate equation is then solved locally for the particles within the ionizing radiation field. Using test calculations, we explore the numerical behaviour of the code with respect to the implementation of the time-dependent ionization rate equation. We also test the coupling of the heating caused by the ionization to the hydrodynamical part of the SPHI code.

  5. Hydrodynamics of the Vacuum

    E-Print Network [OSTI]

    P. M. Stevenson

    2005-07-30T23:59:59.000Z

    Hydrodynamics is the appropriate "effective theory" for describing any fluid medium at sufficiently long length scales. This paper treats the vacuum as such a medium and derives the corresponding hydrodynamic equations. Unlike a normal medium the vacuum has no linear sound-wave regime; disturbances always "propagate" nonlinearly. For an "empty vacuum" the hydrodynamic equations are familiar ones (shallow water-wave equations) and they describe an experimentally observed phenomenon -- the spreading of a clump of zero-temperature atoms into empty space. The "Higgs vacuum" case is much stranger; pressure and energy density, and hence time and space, exchange roles. The speed of sound is formally infinite, rather than zero as in the empty vacuum. Higher-derivative corrections to the vacuum hydrodynamic equations are also considered. In the empty-vacuum case the corrections are of quantum origin and the post-hydrodynamic description corresponds to the Gross-Pitaevskii equation. I conjecture the form of the post-hydrodynamic corrections in the Higgs case. In the 1+1-dimensional case the equations possess remarkable `soliton' solutions and appear to constitute a new exactly integrable system.

  6. Optical and radiographical characterization of silica aerogel for Cherenkov radiator

    E-Print Network [OSTI]

    Tabata, Makoto; Hatakeyama, Yoshikiyo; Kawai, Hideyuki; Morita, Takeshi; Nishikawa, Keiko

    2012-01-01T23:59:59.000Z

    We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying method enables us to produce highly transparent hydrophobic aerogels with high refractive index by shrinking wet-gels. In order to investigate the uniformity in the density (i.e., refractive index) of an individual aerogel monolith, we use the laser Fraunhofer method, an X-ray absorption technique, and Cherenkov imaging by a ring imaging Cherenkov detector in a beam test. We observed an increase in density at the edge of the aerogel tiles, produced by pin-drying.

  7. Optical and radiographical characterization of silica aerogel for Cherenkov radiator

    E-Print Network [OSTI]

    Makoto Tabata; Ichiro Adachi; Yoshikiyo Hatakeyama; Hideyuki Kawai; Takeshi Morita; Keiko Nishikawa

    2012-07-17T23:59:59.000Z

    We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying method enables us to produce highly transparent hydrophobic aerogels with high refractive index by shrinking wet-gels. In order to investigate the uniformity in the density (i.e., refractive index) of an individual aerogel monolith, we use the laser Fraunhofer method, an X-ray absorption technique, and Cherenkov imaging by a ring imaging Cherenkov detector in a beam test. We observed an increase in density at the edge of the aerogel tiles, produced by pin-drying.

  8. Digital radiographic systems detect boiler tube cracks

    SciTech Connect (OSTI)

    Walker, S. [EPRI, Charlotte, NC (United States)

    2008-06-15T23:59:59.000Z

    Boiler water wall leaks have been a major cause of steam plant forced outages. But conventional nondestructive evaluation techniques have a poor track record of detecting corrosion fatigue cracking on the inside surface of the cold side of waterwall tubing. EPRI is performing field trials of a prototype direct-digital radiographic system that promises to be a game changer. 8 figs.

  9. Hydrodynamic instability in strong media

    SciTech Connect (OSTI)

    Bakhrakh, S.M.; Drennov, O.B.; Kovalev, N.P. [Russian Federal Nuclear Center (Russian Federation)] [and others

    1997-03-05T23:59:59.000Z

    This paper reviews the All Russian Scientific Research Institute of Experimental Physics open publications on hydrodynamic instability in strong media.

  10. Skew resisting hydrodynamic seal

    DOE Patents [OSTI]

    Conroy, William T. (Pearland, TX); Dietle, Lannie L. (Sugar Land, TX); Gobeli, Jeffrey D. (Houston, TX); Kalsi, Manmohan S. (Houston, TX)

    2001-01-01T23:59:59.000Z

    A novel hydrodynamically lubricated compression type rotary seal that is suitable for lubricant retention and environmental exclusion. Particularly, the seal geometry ensures constraint of a hydrodynamic seal in a manner preventing skew-induced wear and provides adequate room within the seal gland to accommodate thermal expansion. The seal accommodates large as-manufactured variations in the coefficient of thermal expansion of the sealing material, provides a relatively stiff integral spring effect to minimize pressure-induced shuttling of the seal within the gland, and also maintains interfacial contact pressure within the dynamic sealing interface in an optimum range for efficient hydrodynamic lubrication and environment exclusion. The seal geometry also provides for complete support about the circumference of the seal to receive environmental pressure, as compared the interrupted character of seal support set forth in U.S. Pat. Nos. 5,873,576 and 6,036,192 and provides a hydrodynamic seal which is suitable for use with non-Newtonian lubricants.

  11. Annual Report 2006 for Hydrodynamics and Radiation Hydrodynamics with Astrophysical Applications

    SciTech Connect (OSTI)

    R. Paul Drake

    2007-04-05T23:59:59.000Z

    We report the ongoing work of our group in hydrodynamics and radiation hydrodynamics with astrophysical applications. During the period of the existing grant, we have carried out two types of experiments at the Omega laser. One set of experiments has studied radiatively collapsing shocks, obtaining data using a backlit pinhole with a 100 ps backlighter and beginning to develop the ability to look into the shock tube with optical or x-ray diagnostics. Other experiments have studied the deeply nonlinear development of the Rayleigh-Taylor (RT) instability from complex initial conditions, using dual-axis radiographic data with backlit pinholes and ungated detectors to complete the data set for a Ph.D. student. We lead a team that is developing a proposal for experiments at the National Ignition Facility and are involved in experiments at NIKE and LIL. All these experiments have applications to astrophysics, discussed in the corresponding papers. We assemble the targets for the experiments at Michigan, where we also prepare many of the simple components. We also have several projects underway in our laboratory involving our x-ray source. The above activities, in addition to a variety of data analysis and design projects, provide good experience for graduate and undergraduates students. In the process of doing this research we have built a research group that uses such work to train junior scientists.

  12. Simple Waves in Ideal Radiation Hydrodynamics

    E-Print Network [OSTI]

    Bryan M. Johnson

    2008-11-24T23:59:59.000Z

    In the dynamic diffusion limit of radiation hydrodynamics, advection dominates diffusion; the latter primarily affects small scales and has negligible impact on the large scale flow. The radiation can thus be accurately regarded as an ideal fluid, i.e., radiative diffusion can be neglected along with other forms of dissipation. This viewpoint is applied here to an analysis of simple waves in an ideal radiating fluid. It is shown that much of the hydrodynamic analysis carries over by simply replacing the material sound speed, pressure and index with the values appropriate for a radiating fluid. A complete analysis is performed for a centered rarefaction wave, and expressions are provided for the Riemann invariants and characteristic curves of the one-dimensional system of equations. The analytical solution is checked for consistency against a finite difference numerical integration, and the validity of neglecting the diffusion operator is demonstrated. An interesting physical result is that for a material component with a large number of internal degrees of freedom and an internal energy greater than that of the radiation, the sound speed increases as the fluid is rarefied. These solutions are an excellent test for radiation hydrodynamic codes operating in the dynamic diffusion regime. The general approach may be useful in the development of Godunov numerical schemes for radiation hydrodynamics.

  13. abnormal chest radiograph: Topics by E-print Network

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

    Wright, John Winston 2012-06-07 40 Optical and radiographical characterization of silica aerogel for Cherenkov radiator Nuclear Experiment (arXiv) Summary: We present optical and...

  14. abnormal radiographic findings: Topics by E-print Network

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

    Wright, John Winston 2012-06-07 28 Optical and radiographical characterization of silica aerogel for Cherenkov radiator Nuclear Experiment (arXiv) Summary: We present optical and...

  15. Radiographic X-Ray Pulse Jitter

    SciTech Connect (OSTI)

    Mitton, C. V., Good, D. E., Henderson, D. J., Hogge, K. W.

    2011-01-15T23:59:59.000Z

    The Dual Beam Radiographic Facility consists of two identical radiographic sources. Major components of the machines are: Marx generator, water-filled pulse-forming line (PFL), water-filled coaxial transmission line, three-cell inductive voltage adder, and rod-pinch diode. The diode pulse has the following electrical specifications: 2.25-MV, 60-kA, 60-ns. Each source has the following x-ray parameters: 1-mm-diameter spot size, 4-rad at 1 m, 50-ns full width half max. The x-ray pulse is measured with PIN diode detectors. The sources were developed to produce high resolution images on single-shot, high-value experiments. For this application it is desirable to maintain a high level of reproducibility in source output. X-ray pulse jitter is a key metric for analysis of reproducibility. We will give measurements of x-ray jitter for each machine. It is expected that x-ray pulse jitter is predominantly due to PFL switch jitter, and therefore a correlation of the two will be discussed.

  16. Load responsive hydrodynamic bearing

    DOE Patents [OSTI]

    Kalsi, Manmohan S. (Houston, TX); Somogyi, Dezso (Sugar Land, TX); Dietle, Lannie L. (Stafford, TX)

    2002-01-01T23:59:59.000Z

    A load responsive hydrodynamic bearing is provided in the form of a thrust bearing or journal bearing for supporting, guiding and lubricating a relatively rotatable member to minimize wear thereof responsive to relative rotation under severe load. In the space between spaced relatively rotatable members and in the presence of a liquid or grease lubricant, one or more continuous ring shaped integral generally circular bearing bodies each define at least one dynamic surface and a plurality of support regions. Each of the support regions defines a static surface which is oriented in generally opposed relation with the dynamic surface for contact with one of the relatively rotatable members. A plurality of flexing regions are defined by the generally circular body of the bearing and are integral with and located between adjacent support regions. Each of the flexing regions has a first beam-like element being connected by an integral flexible hinge with one of the support regions and a second beam-like element having an integral flexible hinge connection with an adjacent support region. A least one local weakening geometry of the flexing region is located intermediate the first and second beam-like elements. In response to application of load from one of the relatively rotatable elements to the bearing, the beam-like elements and the local weakening geometry become flexed, causing the dynamic surface to deform and establish a hydrodynamic geometry for wedging lubricant into the dynamic interface.

  17. Effects on the Physical Environment (Hydrodynamics, Sediment...

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

    Effects on the Physical Environment (Hydrodynamics, Sediment Transport, and Water Quality) Effects on the Physical Environment (Hydrodynamics, Sediment Transport, and Water...

  18. Hydrodynamic Testing Facilities Database | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof Energy 2,AUDIT REPORTEnergyFarms AHefei

  19. Hydrodynamic Testing Facilities Database | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetecGtel JumpCounty, Texas: EnergyHy9 CorporationHydra FuelLtdFacilities

  20. Measurements of static loading characteristics of a Flexurepivot Tilt Pad Hydrodynamic Bearing

    E-Print Network [OSTI]

    Walton, Nicholas Van Edward

    1995-01-01T23:59:59.000Z

    An experimental investigation examining the static loading characteristics of a four-pad, KMC FLEXUREPIVOT Tilt Pad Hydrodynamic Bearing is presented. Tests are conducted on the TRACE Fluid Film Bearing Element Test Rig for journal speeds ranging...

  1. Hydrodynamics of Holographic Superconductors

    E-Print Network [OSTI]

    Irene Amado; Matthias Kaminski; Karl Landsteiner

    2009-06-17T23:59:59.000Z

    We study the poles of the retarded Green functions of a holographic superconductor. The model shows a second order phase transition where a charged scalar operator condenses and a U(1) symmetry is spontaneously broken. The poles of the holographic Green functions are the quasinormal modes in an AdS black hole background. We study the spectrum of quasinormal frequencies in the broken phase, where we establish the appearance of a massless or hydrodynamic mode at the critical temperature as expected for a second order phase transition. In the broken phase we find the pole representing second sound. We compute the speed of second sound and its attenuation length as function of the temperature. In addition we find a pseudo diffusion mode, whose frequencies are purely imaginary but with a non-zero gap at zero momentum. This gap goes to zero at the critical temperature. As a technical side result we explain how to calculate holographic Green functions and their quasinormal modes for a set of operators that mix under the RG flow.

  2. appendicular skeletal radiographs: Topics by E-print Network

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

    Summary: We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying...

  3. alimentary lymphosarcoma radiographic: Topics by E-print Network

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

    Summary: We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying...

  4. anteroposterior pelvic radiographs: Topics by E-print Network

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

    Summary: We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying...

  5. advanced radiographic practice: Topics by E-print Network

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

    Summary: We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying...

  6. aggressive radiographic features: Topics by E-print Network

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

    Summary: We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying...

  7. advanced radiographic capability: Topics by E-print Network

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

    Summary: We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying...

  8. age radiographic severity: Topics by E-print Network

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

    Summary: We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying...

  9. Evaluation of the effectiveness of a radiographic anatomy tutorial

    E-Print Network [OSTI]

    Lewis, Cheri MacFarlane

    2001-01-01T23:59:59.000Z

    This study evaluated the effectiveness of computer assisted instruction (CAI) in radiographic anatomy of the equine distal forelimb and also investigated the roles played by amount of tutorial use and achievement level of the user. The participants...

  10. A new shock-capturing numerical scheme for ideal hydrodynamics

    E-Print Network [OSTI]

    Zuzana Feckova; Boris Tomasik

    2015-01-07T23:59:59.000Z

    We present a new algorithm for solving ideal relativistic hydrodynamics based on Godunov method with an exact solution of Riemann problem for an arbitrary equation of state. Standard numerical tests are executed, such as the sound wave propagation and the shock tube problem. Low numerical viscosity and high precision are attained with proper discretization.

  11. A new shock-capturing numerical scheme for ideal hydrodynamics

    E-Print Network [OSTI]

    Feckova, Zuzana

    2015-01-01T23:59:59.000Z

    We present a new algorithm for solving ideal relativistic hydrodynamics based on Godunov method with an exact solution of Riemann problem for an arbitrary equation of state. Standard numerical tests are executed, such as the sound wave propagation and the shock tube problem. Low numerical viscosity and high precision are attained with proper discretization.

  12. IDENTIFICATION OF UNDERWATER VEHICLE HYDRODYNAMIC COEFFICIENTS USING FREE

    E-Print Network [OSTI]

    Johansen, Tor Arne

    been an ever increasing num- ber of applications for unmanned underwater vehicles (UUV) in variousIDENTIFICATION OF UNDERWATER VEHICLE HYDRODYNAMIC COEFFICIENTS USING FREE DECAY TESTS Andrew Ross the potential accuracy of these new methods. Copyright c 2004 IFAC. Keywords: Low-speed underwater vehicles

  13. Formation Interuniversitaire de Physique Hydrodynamics

    E-Print Network [OSTI]

    Balbus, Steven

    Formation Interuniversitaire de Physique Module : Hydrodynamics S. Balbus 1 #12;TO LEARN.8.3 Piston Driven into Gas Cylinder . . . . . . . . . . . . . 73 4.8.4 Driven Acoustic Modes . . . . . . . . . . . . . . . . 110 6.2.3 Inertial Drag of a Sphere by an Ideal Fluid . . . . . . . 113 6.3 Line Vortices and Flow

  14. DATA ASSIMILATION IN HYDRODYNAMIC MODELS

    E-Print Network [OSTI]

    modelling and Kalman filters. The thesis consists of a summary report and a collection of seven researchDATA ASSIMILATION IN HYDRODYNAMIC MODELS OF CONTINENTAL SHELF SEAS Jacob Viborg Tornfeldt Sørensen Informatics and Mathematical Modelling Technical University of Denmark Ph.D. Thesis No. 126 Kgs. Lyngby 2004

  15. Dynamical Spacetimes from Numerical Hydrodynamics

    E-Print Network [OSTI]

    Allan Adams; Nathan Benjamin; Arvin Moghaddam; Wojciech Musial

    2014-11-07T23:59:59.000Z

    We numerically construct dynamical asymptotically-AdS$_4$ metrics by evaluating the fluid/gravity metric on numerical solutions of dissipative hydrodynamics in (2+1) dimensions. The resulting numerical metrics satisfy Einstein's equations in (3+1) dimensions to high accuracy.

  16. Topological groundwater hydrodynamics Garrison Sposito

    E-Print Network [OSTI]

    Chen, Yiling

    Topological groundwater hydrodynamics Garrison Sposito Department of Civil and Environmental; received in revised form 10 November 2000; accepted 15 November 2000 Abstract Topological groundwater, the topological characteristics of groundwater ¯ows governed by the Darcy law are studied. It is demonstrated that

  17. Hydrodynamic Lyapunov Modes in Translation Invariant Systems

    E-Print Network [OSTI]

    Hydrodynamic Lyapunov Modes in Translation Invariant Systems Jean­Pierre Eckmann and Omri Gat De modes in the slowly growing part of the Lyapunov spectrum, which are analogous to the hydrodynamic modes)]. The hydrodynamic Lyapunov vectors loose the typical random structure and exhibit instead the structure of weakly

  18. Hydrodynamic Lyapunov Modes in Translation Invariant Systems

    E-Print Network [OSTI]

    Eckmann, Jean-Pierre

    Hydrodynamic Lyapunov Modes in Translation Invariant Systems Jean­Pierre Eckmann and Omri Gat De modes in the slowly growing part of the Lyapunov spectrum, which are analogous to the hydrodynamic modes)]. The hydrodynamic Lyapunov vectors loose the typical random structure and exhibit instead the structure of weakly

  19. Unusual thoracic radiographic findings in children treated for Hodgkin's disease

    SciTech Connect (OSTI)

    Jochelson, M.S.; Tarbell, N.J.; Weinstein, H.J.

    1986-06-01T23:59:59.000Z

    Mantle irradiation is often part of the treatment for Hodgkin's disease. Localized pneumonitis and fibrosis are well-known sequelae of this treatment. We report nine patients with unusual thoracic radiographic findings following treatment for Hodgkin's disease. All nine had mediastinal widening. Seven of these patients received combined modality therapy in which prednisone was given with their MOPP. In these seven patients, an increase in mediastinal width developed at the same time as the radiographic changes of radiation pneumonitis. Two patients developed bilateral infiltrates extending beyond the field of radiation to the lung periphery. In one of these patients, a spontaneous pneumomediastinum developed. One patient underwent mediastinal biopsy that revealed inflammatory changes similar to those seen in radiation pneumonitis. All patients either responded to steroids or had spontaneous regression of radiographic abnormalities supporting the presumed diagnosis of treatment related changes. Recognition of these unusual sequelae of mantle irradiation will aid in differentiating them from infection or tumor and lead to prompt, appropriate treatment.

  20. Ultrafast x-rays: radiographing magnetism Project overview

    E-Print Network [OSTI]

    Haviland, David

    , head of the ultrafast magnetism group. Stanford PULSE is a worldwide renowned centre for ultrafast1 Ultrafast x-rays: radiographing magnetism Project overview The main purpose of the proposed, it is now possible to achieve x-ray pulses that are a few femtoseconds long and that are focused within

  1. PHERMEX: Pulsed High-Energy Radiographic Machine Emitting X rays

    SciTech Connect (OSTI)

    Dick, R.D.

    1981-01-01T23:59:59.000Z

    The PHERMEX facility used to provide flash radiographs of explosives and explosive-driven metal systems is described. With this facility, precision radiographs of large objects containing materials with high atomic number and high density are attainable. PHERMEX encompasses the high-current, three-cavity, 30-MeV linear electron accelerator; the 50-MHz-radiofrequency power source to drive the cavities; timing, firing, and signal detection system; and a data-acquisition system. Some unique features of PHERMEX are reliability; very intensive submicrosecond bremsstrahlung source rich in 4- to 8-MeV x rays; less than 1.0-mm-diam spot size; precision determination of edges, discontinuities, and areal-mass distribution; and flash radiographs of large explosive systems close to the x-ray target. Some aspects of the PHERMEX-upgrading program are discussed. The program will result (1) in an increased electron-beam energy to about 50 MeV, (2) the use of an electron-gun pulser that is capable of producing three time-adjustable pulses for obtaining three radiographic pictures of a single explosive event, (3) an increased electron injection energy of 1.25 MeV, (4) the capability for recording high-speed signals, and (5) the use of computers to assist the monitoring and control of the data-acquisition system and the PHERMEX accelerator.

  2. RELIABLE RADIOGRAPHIC INSPECTION OF FLEXIBLE RISERS FOR THE OIL INDUSTRY

    SciTech Connect (OSTI)

    Almeida, Romulo M.; Rebello, Joao Marcos A. [Department of Metallurgical and Materials Engineering COPPE/UFRJ-Federal University of Rio de Janeiro P.O. Box 68505 CEP 21941-972, Rio de Janeiro RJ (Brazil); Vaz, Murilo A. [Department of Ocean Engineering-COPPE/UFRJ (Brazil)

    2010-02-22T23:59:59.000Z

    Flexible risers are composite tubular structures manufactured by the concentric assemblage of cylindrical polymeric and helically wound metallic layers employed to convey pressurized fluids such as oil, gas and water in the ocean environment. The metallic layers account for the flexible risers' structural strength and are dimensioned according to the static and dynamic loads. They are usually installed in a free hanging catenary configuration and are subjected to the direct action of waves and marine currents and wave induced motions from the oil production platform. The fatigue rupture of wire armours in the end fitting or within the riser segment protected by the bend stiffener is an object of major concern. Integrity models have been developed, however inspection techniques are mandatory to ensure that failure is detected. Gammagraphy has been used as a common inspection technique in all regions of the flexible riser, mainly with the single wall-single view method. On the other side, there is not any qualified radiographic procedure to this kind of structure. Radiographic simulation was adopted and its validation with actual gammagraphies and establishment of radiographic parameters to complex radiation geometries were done. Results show the viability of the radiographic inspection analyzing the armour wires' rupture and the displacement between wires.

  3. CHARACTERIZATION OF THE ADVANCED RADIOGRAPHIC CAPABILITY FRONT END ON NIF

    SciTech Connect (OSTI)

    Haefner, C; Heebner, J; Dawson, J; Fochs, S; Shverdin, M; Crane, J K; Kanz, V K; Halpin, J; Phan, H; Sigurdsson, R; Brewer, W; Britten, J; Brunton, G; Clark, W; Messerly, M J; Nissen, J D; Nguyen, H; Shaw, B; Hackel, R; Hermann, M; Tietbohl, G; Siders, C W; Barty, C J

    2009-07-15T23:59:59.000Z

    We have characterized the Advanced Radiographic Capability injection laser system and demonstrated that it meets performance requirements for upcoming National Ignition Facility fusion experiments. Pulse compression was achieved with a scaled down replica of the meter-scale grating ARC compressor and sub-ps pulse duration was demonstrated at the Joule-level.

  4. An Owner's Guide to Smoothed Particle Hydrodynamics

    E-Print Network [OSTI]

    T. J. Martin; F. R. Pearce; P. A. Thomas

    1993-10-13T23:59:59.000Z

    We present a practical guide to Smoothed Particle Hydrodynamics (\\SPH) and its application to astrophysical problems. Although remarkably robust, \\SPH\\ must be used with care if the results are to be meaningful since the accuracy of \\SPH\\ is sensitive to the arrangement of the particles and the form of the smoothing kernel. In particular, the initial conditions for any \\SPH\\ simulation must consist of particles in dynamic equilibrium. We describe some of the numerical difficulties that may be encountered when using \\SPH, and how these may be overcome. Through our experience in using \\SPH\\ code to model convective stars, galaxy clusters and large scale structure problems we have developed many diagnostic tests. We give these here as an aid to rapid identification of errors, together with a list of basic prerequisites for the most efficient implementation of \\SPH.

  5. Introduction and guide to LLNL's relativistic 3-D nuclear hydrodynamics code

    SciTech Connect (OSTI)

    Zingman, J.A.; McAbee, T.L.; Alonso, C.T.; Wilson, J.R.

    1987-11-01T23:59:59.000Z

    We have constructed a relativistic hydrodynamic model to investigate Bevalac and higher energy, heavy-ion collisions. The basis of the model is a finite-difference solution to covariant hydrodynamics, which will be described in the rest of this paper. This paper also contains: a brief review of the equations and numerical methods we have employed in the solution to the hydrodynamic equations, a detailed description of several of the most important subroutines, and a numerical test on the code. 30 refs., 8 figs., 1 tab.

  6. COSMOS: A Radiation-Chemo-Hydrodynamics Code for Astrophysical Problems

    E-Print Network [OSTI]

    Peter Anninos; P. Chris Fragile; Stephen D. Murray

    2003-03-10T23:59:59.000Z

    We have developed a new massively-parallel radiation-hydrodynamics code (Cosmos) for Newtonian and relativistic astrophysical problems that also includes radiative cooling, self-gravity, and non-equilibrium, multi-species chemistry. Several numerical methods are implemented for the hydrodynamics, including options for both internal and total energy conserving schemes. Radiation is treated using flux-limited diffusion. The chemistry incorporates 27 reactions, including both collisional and radiative processes for atomic hydrogen and helium gases, and molecular hydrogen chains. In this paper we discuss the equations and present results from test problems carried out to verify the robustness and accuracy of our code in the Newtonian regime. An earlier paper presented tests of the relativistic capabilities of Cosmos.

  7. COSMOS A Radiation-Chemo-Hydrodynamics Code for Astrophysical Problems

    E-Print Network [OSTI]

    Anninos, P; Murray, S D; Anninos, Peter; Murray, Stephen D.

    2003-01-01T23:59:59.000Z

    We have developed a new massively-parallel radiation-hydrodynamics code (Cosmos) for Newtonian and relativistic astrophysical problems that also includes radiative cooling, self-gravity, and non-equilibrium, multi-species chemistry. Several numerical methods are implemented for the hydrodynamics, including options for both internal and total energy conserving schemes. Radiation is treated using flux-limited diffusion. The chemistry incorporates 27 reactions, including both collisional and radiative processes for atomic hydrogen and helium gases, and molecular hydrogen chains. In this paper we discuss the equations and present results from test problems carried out to verify the robustness and accuracy of our code in the Newtonian regime. An earlier paper presented tests of the relativistic capabilities of Cosmos.

  8. Foundation of Hydrodynamics of Strongly Interacting Systems

    SciTech Connect (OSTI)

    Wong, Cheuk-Yin [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    Hydrodynamics and quantum mechanics have many elements in common, as the density field and velocity fields are common variables that can be constructed in both descriptions. Starting with the Schroedinger equation and the Klein-Gordon for a single particle in hydrodynamical form, we examine the basic assumptions under which a quantum system of particles interacting through their mean fields can be described by hydrodynamics.

  9. Hydrodynamic experiment conducted in Nevada | National Nuclear...

    National Nuclear Security Administration (NNSA)

    Leda involve non-nuclear surrogate materials that mimic many of the properties of nuclear materials. Hydrodynamics refers to the physics involved when solids, under extreme...

  10. Ergoregion instability: The hydrodynamic vortex

    E-Print Network [OSTI]

    Leandro A. Oliveira; Vitor Cardoso; Luís C. B. Crispino

    2014-05-16T23:59:59.000Z

    Four-dimensional, asymptotically flat spacetimes with an ergoregion but no horizon have been shown to be linearly unstable against a superradiant-triggered mechanism. This result has wide implications in the search for astrophysically viable alternatives to black holes, but also in the understanding of black holes and Hawking evaporation. Here we investigate this instability in detail for a particular setup which can be realized in the laboratory: the {\\it hydrodynamic vortex}, an effective geometry for sound waves, with ergoregion and without an event horizon.

  11. Disruptive Innovation in Numerical Hydrodynamics

    SciTech Connect (OSTI)

    Waltz, Jacob I. [Los Alamos National Laboratory

    2012-09-06T23:59:59.000Z

    We propose the research and development of a high-fidelity hydrodynamic algorithm for tetrahedral meshes that will lead to a disruptive innovation in the numerical modeling of Laboratory problems. Our proposed innovation has the potential to reduce turnaround time by orders of magnitude relative to Advanced Simulation and Computing (ASC) codes; reduce simulation setup costs by millions of dollars per year; and effectively leverage Graphics Processing Unit (GPU) and future Exascale computing hardware. If successful, this work will lead to a dramatic leap forward in the Laboratory's quest for a predictive simulation capability.

  12. An Optical Streak Diagnostic for Observing Anode-Cathode Plasmas for Radiographic Source Development

    SciTech Connect (OSTI)

    Droemer, Darryl W. [National Security Technologies, LLC; Crain, Marlon D.; Lare, Gregory A. [National Security Technologies, LLC; Bennett, Nichelle L. [National Security Technologies, LLC; Johnston, Mark D. [Sandia National Laboratories

    2013-06-13T23:59:59.000Z

    National Security Technologies, LLC, and Sandia National Laboratories are collaborating in the development of pulsed power–driven flash x-ray radiographic sources that utilize high-intensity electron beam diodes. The RITS 6 (Radiographic Integrated Test Stand) accelerator at Sandia is used to drive a self magnetic pinch diode to produce a Bremsstrahlung x-ray source. The high electric fields and current densities associated with these short A-K gap pinch beam diodes present many challenges in diode development. Plasmas generated at both the anode and cathode affect the diode performance, which is manifested in varying spot (source) sizes, total dose output, and impedance profiles. Understanding the nature of these plasmas including closure rates and densities is important in modeling their behavior and providing insight into their mitigation. In this paper we describe a streak camera–based optical diagnostic that is capable of observing and measuring plasma evolution within the A-K gap. By imaging a region of interest onto the input slit of a streak camera, we are able to produce a time-resolved one-dimensional image of the evolving plasma. Typical data are presented.

  13. Hydrodynamic forces on piggyback pipelines

    SciTech Connect (OSTI)

    Jakobsen, M.L.; Sayer, P. [Univ. of Strathclyde, Glasgow (United Kingdom)

    1995-12-31T23:59:59.000Z

    An increasing number of new offshore pipelines have been designed as bundles, mainly because of overall cost reductions. One popular way of combining two pipelines with different diameters is the piggyback configuration, with the smaller pipeline strapped on top of the main pipeline. The external hydrodynamic forces on this combination are at present very roughly estimated; pipeline engineers need more data to support their designs. This paper presents experimental results for the in-line hydrodynamic loading on three different piggyback set-ups. The models comprised a 0.4 m main pipeline, and three piggyback pipelines with diameters of 0.038 m, 0.059 m and 0.099 m. Each small pipeline was separately mounted to the main pipeline, with a gap equal to its own diameter. These model sizes lie approximately between half- and full-scale. Experiments were undertaken for K{sub C} between 5 and 42, and R{sub e} in the range 0.0 * 10{sup 4} to 8.5 * 10{sup 5}. The results based on Morison`s equation indicate that a simple addition of the separate forces acting on each cylinder underestimates the actual force by up to 35% at low K{sub C} (< {approximately} 10) and by as much as 100% in the drag-dominated regime (K{sub C} > {approximately} 20).

  14. Application of Perona Malik anisotropic diffusion on digital radiographic image

    SciTech Connect (OSTI)

    Halim, Suhaila Abd; Razak, Rohayu Abdul; Ibrahim, Arsmah [Center of Mathematics Studies, Faculty of Computer and Mathematical Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor DE (Malaysia); Manurung, Yupiter HP [Advanced Manufacturing Technology Center, Faculty of Mechanical Engineering, Universiti Teknologi MARA, 40450 Shah Alam, Selangor DE (Malaysia)

    2014-07-10T23:59:59.000Z

    Perona Malik Anisotropic Diffusion (PMAD) is a very useful and efficient denoising technique if the parameters are properly selected. Overestimating the parameters may cause oversmoothed and underestimating it may leave unfiltered noise. This makes the selection of parameters a crucial process. In this paper the PMAD model is solved using a finite difference scheme The discretized model is evaluated using different diffusion coefficient of exponential and quadratic on defective radiographic images in terms of quality and efficiency. In the application of the PMAD model on image data, a set of defective radiographic images of welding is used as input data. Peak Signal to Noise Ratio (PSNR), Structural Similarity Measure (SSIM) and temporal time are used to evaluate the performance of the model. The implementation of the experiment has been carried out using MATLAB R2009a. In terms of quality, results show that the Quadratic Diffusion Coefficient Function (QDCF) provides better results compared with the Exponential Diffusion Coefficient Function (EDCF). In conclusion, the denoising effect using PMAD model based on finite difference scheme shows able to improve image quality by removing noise in the defective radiographic image.

  15. Hydrodynamic Modeling and the QGP Shear Viscosity

    E-Print Network [OSTI]

    Huichao Song

    2012-07-10T23:59:59.000Z

    In this article, we will briefly review the recent progress on hydrodynamic modeling and the extraction of the quark-gluon plasma (QGP) specific shear viscosity with an emphasis on results obtained from the hybrid model VISHNU that couples viscous hydrodynamics for the macroscopic expansion of the QGP to the hadron cascade model for the microscopic evolution of the late hadronic stage.

  16. Causal dissipative hydrodynamics for heavy ion collisions

    E-Print Network [OSTI]

    Chaudhuri, A K

    2011-01-01T23:59:59.000Z

    We briefly discuss the recent developments in causal dissipative hydrodynamic for relativistic heavy ion collisions. Phenomenological estimate of QGP viscosity over entropy ratio from several experimental data, e.g. STAR's $\\phi$ meson data, centrality dependence of elliptic flow, universal scaling elliptic flow etc. are discussed. QGP viscosity, extracted from hydrodynamical model analysis can have very large systematic uncertainty due to uncertain initial conditions.

  17. Causal dissipative hydrodynamics for heavy ion collisions

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2011-01-23T23:59:59.000Z

    We briefly discuss the recent developments in causal dissipative hydrodynamic for relativistic heavy ion collisions. Phenomenological estimate of QGP viscosity over entropy ratio from several experimental data, e.g. STAR's $\\phi$ meson data, centrality dependence of elliptic flow, universal scaling elliptic flow etc. are discussed. QGP viscosity, extracted from hydrodynamical model analysis can have very large systematic uncertainty due to uncertain initial conditions.

  18. Effects on the Physical Environment (Hydrodynamics, and Water...

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

    and Water Quality Food Web) Effects on the Physical Environment (Hydrodynamics, and Water Quality Food Web) Effects on the Physical Environment (Hydrodynamics, and Water Quality...

  19. A smoothed particle hydrodynamics model for reactive transport...

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

    A smoothed particle hydrodynamics model for reactive transport and mineral precipitation in porous and fractured porous media. A smoothed particle hydrodynamics model for reactive...

  20. Hydrodynamic force characteristics in the splash zone

    SciTech Connect (OSTI)

    Daliri, M.R.; Haritos, N. [Univ. of Melbourne, Parkville, Victoria (Australia). Dept. of Civil and Environmental Engineering

    1996-12-31T23:59:59.000Z

    A comprehensive experimental study concerned with the hydrodynamic force characteristics of both rigid and compliant surface piercing cylinders, with a major focus on the local nature of these characteristics as realized in the splash zone and in the fully submerged zone immediately below this region, has been in progress at the University of Melbourne for the last three years. This paper concentrates on a portion of this study associated with uni-directional regular wave inputs with wave steepness (H/{lambda}) in the range 0.0005--0.1580 and Keulegan-Carpenter (KC) numbers in the range 2--15 which encompasses inertia force dominant (KC<5) to drag force significant conditions (5tests. The measured wave forces at different elevations have been interpreted using the Morison equation to determine experimental values of force coefficients C{sub D} and C{sub M}. The results in hand suggest that both C{sub D} and C{sub M} values in the splash zone are higher and exhibit a mild frequency dependence in comparison with their corresponding counterparts for the fully submerged segments. For weakly nonlinear waves (H/{lambda}<0.1) only wave fluctuation is found to be important and any mild nonlinearities do not significantly affect the test model force response and consequently the force coefficient values. However, for relatively nonlinear waves (0.1test model force response, producing ringing effects in conducive conditions.

  1. Outpatient radiographic exposure in the first five years of life

    SciTech Connect (OSTI)

    Fosarelli, P.D.; DeAngelis, C.

    1987-06-01T23:59:59.000Z

    Young children receive a variety of diagnostic radiographs over time. In some cases the exposure to radiation may be unwarranted because the films may yield confusing results, or may also need to be repeated because of poor technical quality. Even when the results are clearly negative, the subsequent treatment may proceed as if the film had been positive because of the child's clinical condition. The cumulative effect of such low-dose radiation on infants and children over time is unknown. The number and types of outpatient radiographs received by a cohort of poor children from a hospital-based continuity clinic during their first 5 years of life were reviewed. Also noted were the reason for obtaining the film, whether it was positive for that reason or another, whether the child had a chronic condition that prompted the use of radiograph, and the child's sex, race, and age when the film was obtained. Of the 218 children, 132 (60.6%) received 349 sets of films in their first 5 years. There was no difference in the number of films by race or sex. Chest and posttrauma bone or joint films accounted for 315 sets of films or 90.3% of the total. Overall, 25.8% of the 267 chest films were positive; this varied by age. Only 15% of the chest films were positive in the first year compared with 29 to 49% in the second through fifth years (p less than 0.001). Cough was the respiratory symptom most reliably associated with a positive chest film, both for the cohort (p less than 0.0001) and for children in the first year of life (p less than 0.01).

  2. SC Brochure_Final_10dec12.indd

    National Nuclear Security Administration (NNSA)

    at the Dual Axis Radiographic Hydrodynamic Test Facility houses the equipment used to control, calibrate, and monitor the ultra high- power x-ray imaging of materials that...

  3. Solving the viscous hydrodynamics order by order

    E-Print Network [OSTI]

    Jian-Hua Gao; Shi Pu

    2014-09-02T23:59:59.000Z

    In this paper, we propose a method of solving the viscous hydrodynamics order by order in a derivative expansion. In such method, the zero order solution is just the one of the ideal hydrodynamics. All the other higher order corrections satisfy the same first-order partial differential equations but with different inhomogeneous terms. We therefore argue that our method could be easily extended to any orders. The problem of causality and stability will be released if the gradient expansion is guaranteed. This method might be of great help to both theoretical and numerical calculations of relativistic hydrodynamics.

  4. An implicit Smooth Particle Hydrodynamic code

    SciTech Connect (OSTI)

    Charles E. Knapp

    2000-04-01T23:59:59.000Z

    An implicit version of the Smooth Particle Hydrodynamic (SPH) code SPHINX has been written and is working. In conjunction with the SPHINX code the new implicit code models fluids and solids under a wide range of conditions. SPH codes are Lagrangian, meshless and use particles to model the fluids and solids. The implicit code makes use of the Krylov iterative techniques for solving large linear-systems and a Newton-Raphson method for non-linear corrections. It uses numerical derivatives to construct the Jacobian matrix. It uses sparse techniques to save on memory storage and to reduce the amount of computation. It is believed that this is the first implicit SPH code to use Newton-Krylov techniques, and is also the first implicit SPH code to model solids. A description of SPH and the techniques used in the implicit code are presented. Then, the results of a number of tests cases are discussed, which include a shock tube problem, a Rayleigh-Taylor problem, a breaking dam problem, and a single jet of gas problem. The results are shown to be in very good agreement with analytic solutions, experimental results, and the explicit SPHINX code. In the case of the single jet of gas case it has been demonstrated that the implicit code can do a problem in much shorter time than the explicit code. The problem was, however, very unphysical, but it does demonstrate the potential of the implicit code. It is a first step toward a useful implicit SPH code.

  5. Shear viscosity, cavitation and hydrodynamics at LHC

    E-Print Network [OSTI]

    Jitesh R. Bhatt; Hiranmaya Mishra; V. Sreekanth

    2011-09-28T23:59:59.000Z

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

  6. Thermo--hydrodynamics As a Field Theory

    E-Print Network [OSTI]

    Jacek Jezierski; Jerzy Kijowski

    2011-12-26T23:59:59.000Z

    The field theoretical description of thermo-hydrodynamics is given. It is based on the duality between the physical space--time and the "material space-time" which we construct here. The material space appearing in a natural way in the canonical formulation of the hydrodynamics is completed with a material time playing role of the field potential for temperature. Both Lagrangian and Hamiltonian formulations, the canonical structure, Poisson bracket, N\\"other theorem and conservation laws are discussed.

  7. RAM: a Relativistic Adaptive Mesh Refinement Hydrodynamics Code

    SciTech Connect (OSTI)

    Zhang, Wei-Qun; /KIPAC, Menlo Park; MacFadyen, Andrew I.; /Princeton, Inst. Advanced Study

    2005-06-06T23:59:59.000Z

    The authors have developed a new computer code, RAM, to solve the conservative equations of special relativistic hydrodynamics (SRHD) using adaptive mesh refinement (AMR) on parallel computers. They have implemented a characteristic-wise, finite difference, weighted essentially non-oscillatory (WENO) scheme using the full characteristic decomposition of the SRHD equations to achieve fifth-order accuracy in space. For time integration they use the method of lines with a third-order total variation diminishing (TVD) Runge-Kutta scheme. They have also implemented fourth and fifth order Runge-Kutta time integration schemes for comparison. The implementation of AMR and parallelization is based on the FLASH code. RAM is modular and includes the capability to easily swap hydrodynamics solvers, reconstruction methods and physics modules. In addition to WENO they have implemented a finite volume module with the piecewise parabolic method (PPM) for reconstruction and the modified Marquina approximate Riemann solver to work with TVD Runge-Kutta time integration. They examine the difficulty of accurately simulating shear flows in numerical relativistic hydrodynamics codes. They show that under-resolved simulations of simple test problems with transverse velocity components produce incorrect results and demonstrate the ability of RAM to correctly solve these problems. RAM has been tested in one, two and three dimensions and in Cartesian, cylindrical and spherical coordinates. they have demonstrated fifth-order accuracy for WENO in one and two dimensions and performed detailed comparison with other schemes for which they show significantly lower convergence rates. Extensive testing is presented demonstrating the ability of RAM to address challenging open questions in relativistic astrophysics.

  8. RIS-M-2575 REFERENCE NEUTRON RADIOGRAPHS OF NUCLEAR REACTOR FUEL

    E-Print Network [OSTI]

    RISØ-M-2575 REFERENCE NEUTRON RADIOGRAPHS OF NUCLEAR REACTOR FUEL J. C. Domanus Abstract. Reference neutron radiographs of nuclear reactor fuel were produced by the Euraton Neutron Radiography Working Group-conpacted nuclear fuel pins. Those parts of the pins are shown where changes of ap- pearance differ from those

  9. DIGITAL RADIOGRAPHY OF SPECIAL NUCLEAR MATERIAL TEST PACKAGES

    SciTech Connect (OSTI)

    HOWARD, BOYD

    2006-02-02T23:59:59.000Z

    The purpose of this document is to provide a brief introduction to digital radiography (DR), and a description of the DR configuration that was used to radiographically image the Special Nuclear Material (SNM) Test Packages before and after function tests that have been conducted. Also included are (1) Attachment 1, a comprehensive index that describes at which phase of the certification process that digital radiographic images were acquired, (2) digital radiographic images of each of the six packages at various stages of the certification process, and (3) Attachment 2, imaging instructions, that specify the setup procedures and detailed parameters of the DR imaging methodology that were used.

  10. Early hydrodynamic evolution of a stellar collision

    SciTech Connect (OSTI)

    Kushnir, Doron; Katz, Boaz [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States)

    2014-04-20T23:59:59.000Z

    The early phase of the hydrodynamic evolution following the collision of two stars is analyzed. Two strong shocks propagate from the contact surface and move toward the center of each star at a velocity that is a small fraction of the velocity of the approaching stars. The shocked region near the contact surface has a planar symmetry and a uniform pressure. The density vanishes at the (Lagrangian) surface of contact, and the speed of sound diverges there. The temperature, however, reaches a finite value, since as the density vanishes, the finite pressure is radiation dominated. For carbon-oxygen white dwarf (CO WD) collisions, this temperature is too low for any appreciable nuclear burning shortly after the collision, which allows for a significant fraction of the mass to be highly compressed to the density required for efficient {sup 56}Ni production in the detonation wave that follows. This property is crucial for the viability of collisions of typical CO WD as progenitors of type Ia supernovae, since otherwise only massive (>0.9 M {sub ?}) CO WDs would have led to such explosions (as required by all other progenitor models). The divergence of the speed of sound limits numerical studies of stellar collisions, as it makes convergence tests exceedingly expensive unless dedicated schemes are used. We provide a new one-dimensional Lagrangian numerical scheme to achieve this. A self-similar planar solution is derived for zero-impact parameter collisions between two identical stars, under some simplifying assumptions (including a power-law density profile), which is the planar version of previous piston problems that were studied in cylindrical and spherical symmetries.

  11. Depositional environment and hydrodynamic flow in Guadalupian Cherry Canyon sandstone, West Ford and West Geraldine fields, Delaware Basin, Texas 

    E-Print Network [OSTI]

    Linn, Anne Marie

    1985-01-01T23:59:59.000Z

    processes. The burial history of the sandstones includes compaction of sediments and development of quartz over growths, precipitation of clays and cements, decementation, a second precipitation of clays and cements, partial dissolution of cements...) noted that the Wheat field has a tilted oil/water contact implying that hydrodynamic flow is present. The influence of hydrodynamic flow on oil entrapment was determined from the analysis of subsurface pressur es derived from drill stem tests...

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

    E-Print Network [OSTI]

    Peles, Yoav

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

  13. Hydrodynamic simulations of self-phoretic microswimmers

    E-Print Network [OSTI]

    Mingcheng Yang; Adam Wysocki; Marisol Ripoll

    2014-03-04T23:59:59.000Z

    A mesoscopic hydrodynamic model to simulate synthetic self-propelled Janus particles which is thermophoretically or diffusiophoretically driven is here developed. We first propose a model for a passive colloidal sphere which reproduces the correct rotational dynamics together with strong phoretic effect. This colloid solution model employs a multiparticle collision dynamics description of the solvent, and combines potential interactions with the solvent, with stick boundary conditions. Asymmetric and specific colloidal surface is introduced to produce the properties of self-phoretic Janus particles. A comparative study of Janus and microdimer phoretic swimmers is performed in terms of their swimming velocities and induced flow behavior. Self-phoretic microdimers display long range hydrodynamic interactions and can be characterized as pullers or pushers. In contrast, Janus particles are characterized by short range hydrodynamic interactions and behave as neutral swimmers. Our model nicely mimics those recent experimental realization of the self-phoretic Janus particles.

  14. Effects of Second-Order Hydrodynamics on a Semisubmersible Floating Offshore Wind Turbine: Preprint

    SciTech Connect (OSTI)

    Bayati, I.; Jonkman, J.; Robertson, A.; Platt, A.

    2014-07-01T23:59:59.000Z

    The objective of this paper is to assess the second-order hydrodynamic effects on a semisubmersible floating offshore wind turbine. Second-order hydrodynamics induce loads and motions at the sum- and difference-frequencies of the incident waves. These effects have often been ignored in offshore wind analysis, under the assumption that they are significantly smaller than first-order effects. The sum- and difference-frequency loads can, however, excite eigenfrequencies of the system, leading to large oscillations that strain the mooring system or vibrations that cause fatigue damage to the structure. Observations of supposed second-order responses in wave-tank tests performed by the DeepCwind consortium at the MARIN offshore basin suggest that these effects might be more important than originally expected. These observations inspired interest in investigating how second-order excitation affects floating offshore wind turbines and whether second-order hydrodynamics should be included in offshore wind simulation tools like FAST in the future. In this work, the effects of second-order hydrodynamics on a floating semisubmersible offshore wind turbine are investigated. Because FAST is currently unable to account for second-order effects, a method to assess these effects was applied in which linearized properties of the floating wind system derived from FAST (including the 6x6 mass and stiffness matrices) are used by WAMIT to solve the first- and second-order hydrodynamics problems in the frequency domain. The method has been applied to the OC4-DeepCwind semisubmersible platform, supporting the NREL 5-MW baseline wind turbine. The loads and response of the system due to the second-order hydrodynamics are analysed and compared to first-order hydrodynamic loads and induced motions in the frequency domain. Further, the second-order loads and induced response data are compared to the loads and motions induced by aerodynamic loading as solved by FAST.

  15. Bounce-free spherical hydrodynamic implosion

    SciTech Connect (OSTI)

    Kagan, Grigory; Tang Xianzhu; Hsu, Scott C.; Awe, Thomas J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2011-12-15T23:59:59.000Z

    In a bounce-free spherical hydrodynamic implosion, the post-stagnation hot core plasma does not expand against the imploding flow. Such an implosion scheme has the advantage of improving the dwell time of the burning fuel, resulting in a higher fusion burn-up fraction. The existence of bounce-free spherical implosions is demonstrated by explicitly constructing a family of self-similar solutions to the spherically symmetric ideal hydrodynamic equations. When applied to a specific example of plasma liner driven magneto-inertial fusion, the bounce-free solution is found to produce at least a factor of four improvement in dwell time and fusion energy gain.

  16. Dissipative hydrodynamics in 2+1 dimensions

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2007-03-12T23:59:59.000Z

    In a first order theory of dissipative hydrodynamics, we have simulated hydrodynamic evolution of QGP fluid with dissipation due to shear viscosity only. Simulation confirms that compared to an ideal fluid, energy density or temperature of a viscous fluid evolve slowly. Transverse expansion is also more in viscous fluid. We also study the effect of viscosity on particle production. Particle production is enhanced, more at large $p_T$. The elliptic flow on the otherhand decreases and shows a tendency to saturate at large $p_T$.

  17. Parity Breaking Transport in Lifshitz Hydrodynamics

    E-Print Network [OSTI]

    Carlos Hoyos; Adiel Meyer; Yaron Oz

    2015-05-12T23:59:59.000Z

    We derive the constitutive relations of first order charged hydrodynamics for theories with Lifshitz scaling and broken parity in $2+1$ and $3+1$ spacetime dimensions. In addition to the anomalous (in $3+1$) or Hall (in $2+1$) transport of relativistic hydrodynamics, there is an additional non-dissipative transport allowed by the absence of boost invariance. We analyze the non-relativistic limit and use a phenomenological model of a strange metal to argue that these effects can be measured in principle by using electromagnetic fields with non-zero gradients.

  18. Self-consistent solution of cosmological radiation-hydrodynamics and chemical ionization

    SciTech Connect (OSTI)

    Reynolds, Daniel R. [Mathematics, Southern Methodist University, Dallas, TX 75275-0156 (United States)], E-mail: reynolds@smu.edu; Hayes, John C. [Lawrence Livermore National Lab, P.O. Box 808, L-551, Livermore, CA 94551 (United States)], E-mail: jchayes@llnl.gov; Paschos, Pascal [Ctr. for Astrophysics and Space Sciences, U.C. San Diego, La Jolla, CA 92093 (United States)], E-mail: ppaschos@minbari.ucsd.edu; Norman, Michael L. [Ctr. for Astrophysics and Space Sciences, U.C. San Diego, La Jolla, CA 92093 (United States); Physics Department, U.C. San Diego, La Jolla, CA 92093 (United States)], E-mail: mlnorman@ucsd.edu

    2009-10-01T23:59:59.000Z

    We consider a PDE system comprising compressible hydrodynamics, flux-limited diffusion radiation transport and chemical ionization kinetics in a cosmologically-expanding universe. Under an operator-split framework, the cosmological hydrodynamics equations are solved through the piecewise parabolic method, as implemented in the Enzo community hydrodynamics code. The remainder of the model, including radiation transport, chemical ionization kinetics, and gas energy feedback, form a stiff coupled PDE system, which we solve using a fully-implicit inexact Newton approach, and which forms the crux of this paper. The inner linear Newton systems are solved using a Schur complement formulation, and employ a multigrid-preconditioned conjugate gradient solver for the inner Schur systems. We describe this approach and provide results on a suite of test problems, demonstrating its accuracy, robustness, and scalability to very large problems.

  19. A Moving Frame Algorithm for High Mach Number Hydrodynamics

    E-Print Network [OSTI]

    Hy Trac; Ue-Li Pen

    2003-09-24T23:59:59.000Z

    We present a new approach to Eulerian computational fluid dynamics that is designed to work at high Mach numbers encountered in astrophysical hydrodynamic simulations. The Eulerian fluid conservation equations are solved in an adaptive frame moving with the fluid where Mach numbers are minimized. The moving frame approach uses a velocity decomposition technique to define local kinetic variables while storing the bulk kinetic components in a smoothed background velocity field that is associated with the grid velocity. Gravitationally induced accelerations are added to the grid, thereby minimizing the spurious heating problem encountered in cold gas flows. Separately tracking local and bulk flow components allows thermodynamic variables to be accurately calculated in both subsonic and supersonic regions. A main feature of the algorithm, that is not possible in previous Eulerian implementations, is the ability to resolve shocks and prevent spurious heating where both the preshock and postshock Mach numbers are high. The hybrid algorithm combines the high resolution shock capturing ability of the second-order accurate Eulerian TVD scheme with a low-diffusion Lagrangian advection scheme. We have implemented a cosmological code where the hydrodynamic evolution of the baryons is captured using the moving frame algorithm while the gravitational evolution of the collisionless dark matter is tracked using a particle-mesh N-body algorithm. The MACH code is highly suited for simulating the evolution of the IGM where accurate thermodynamic evolution is needed for studies of the Lyman alpha forest, the Sunyaev-Zeldovich effect, and the X-ray background. Hydrodynamic and cosmological tests are described and results presented. The current code is fast, memory-friendly, and parallelized for shared-memory machines.

  20. NOAA Fisheries Protocols For Hydro-dynamic Dredge Surveys

    E-Print Network [OSTI]

    NOAA Fisheries Protocols For Hydro-dynamic Dredge Surveys: Surf Clams and Ocean Quahogs December 19..................................................................................................................................... 1 NOAA Fisheries Hydro-dynamic Clam Dredge Survey Protocols........................................................................... 5 Clam Dredge Construction and Repair

  1. Stabilizing geometry for hydrodynamic rotary seals

    DOE Patents [OSTI]

    Dietle, Lannie L. (Houston, TX); Schroeder, John E. (Richmond, TX)

    2010-08-10T23:59:59.000Z

    A hydrodynamic sealing assembly including a first component having first and second walls and a peripheral wall defining a seal groove, a second component having a rotatable surface relative to said first component, and a hydrodynamic seal comprising a seal body of generally ring-shaped configuration having a circumference. The seal body includes hydrodynamic and static sealing lips each having a cross-sectional area that substantially vary in time with each other about the circumference. In an uninstalled condition, the seal body has a length defined between first and second seal body ends which varies in time with the hydrodynamic sealing lip cross-sectional area. The first and second ends generally face the first and second walls, respectively. In the uninstalled condition, the first end is angulated relative to the first wall and the second end is angulated relative to the second wall. The seal body has a twist-limiting surface adjacent the static sealing lip. In the uninstalled condition, the twist-limiting surface is angulated relative to the peripheral wall and varies along the circumference. A seal body discontinuity and a first component discontinuity mate to prevent rotation of the seal body relative to the first component.

  2. General Relativity as Geometro-Hydrodynamics

    E-Print Network [OSTI]

    B. L. Hu

    1996-07-29T23:59:59.000Z

    In the spirit of Sakharov's `metric elasticity' proposal, we draw a loose analogy between general relativity and the hydrodynamic state of a quantum gas. In the `top-down' approach, we examine the various conditions which underlie the transition from some candidate theory of quantum gravity to general relativity. Our emphasis here is more on the `bottom-up' approach, where one starts with the semiclassical theory of gravity and examines how it is modified by graviton and quantum field excitations near and above the Planck scale. We mention three aspects based on our recent findings: 1) Emergence of stochastic behavior of spacetime and matter fields depicted by an Einstein-Langevin equation. The backreaction of quantum fields on the classical background spacetime manifests as a fluctuation-dissipation relation. 2) Manifestation of stochastic behavior in effective theories below the threshold arising from excitations above. The implication for general relativity is that such Planckian effects, though exponentially suppressed, is in principle detectable at sub-Planckian energies. 3) Decoherence of correlation histories and quantum to classical transition. From Gell-Mann and Hartle's observation that the hydrodynamic variables which obey conservation laws are most readily decohered, one can, in the spirit of Wheeler, view the conserved Bianchi identity obeyed by the Einstein tensor as an indication that general relativity is a hydrodynamic theory of geometry. Many outstanding issues surrounding the transition to general relativity are of a nature similar to hydrodynamics and mesoscopic physics.

  3. Compressible fluid model for hydrodynamic lubrication cavitation

    E-Print Network [OSTI]

    Sart, Remi

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

  4. Title: Imputation techniques for incomplete radiographic outcome in rheumatoid arthritis randomized trials: a simulation study

    E-Print Network [OSTI]

    Samson, Adeline

    , INSERM U738, Groupe Hospitalier Bichat-Claude Bernard, 46 rue Henri Huchard, 75018 Paris, France. Tel for the management of RA in controlled trials (4, 5) and the radiographic outcome is often used as a primary endpoint

  5. Simulation of radiographic image data transfer and video conferencing over local area networks

    E-Print Network [OSTI]

    Sarker, Nripendra Nath

    1996-01-01T23:59:59.000Z

    capacities considered were 1 and 10 Mbps. The objective was then to find the delay for different combinations of these variables. The possibility of video conferencing was also studied along with the radiographic image transfer. The objective of this work...

  6. Category:Hydrodynamic Testing Facility Type | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model, click here. Category:Conceptual Model Add.pngpage?sourcehelp is welcomed.This

  7. Property:Hydrodynamic Testing Facility Type | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag Jump to: navigation,ProjectStartDate Jump to:Property EditType" Showing 25

  8. Hydrodynamics of rapidly rotating superfluid neutron stars with mutual friction

    E-Print Network [OSTI]

    A. Passamonti; N. Andersson

    2010-04-26T23:59:59.000Z

    We study time evolutions of superfluid neutron stars, focussing on the nature of the oscillation spectrum, the effect of mutual friction force on the oscillations and the hydrodynamical spin-up phase of pulsar glitches. We linearise the dynamical equations of a Newtonian two-fluid model for rapidly rotating backgrounds. In the axisymmetric equilibrium configurations, the two fluid components corotate and are in beta-equilibrium. We use analytical equations of state that generate stratified and non-stratified stellar models, which enable us to study the coupling between the dynamical degrees of freedom of the system. By means of time evolutions of the linearised dynamical equations, we determine the spectrum of axisymmetric and non-axisymmetric oscillation modes, accounting for the contribution of the gravitational potential perturbations, i.e. without adopting the Cowling approximation. We study the mutual friction damping of the superfluid oscillations and consider the effects of the non-dissipative part of the mutual friction force on the mode frequencies. We also provide technical details and relevant tests for the hydrodynamical model of pulsar glitches discussed by Sidery, Passamonti and Andersson (2010). In particular, we describe the method used to generate the initial data that mimic the pre-glitch state, and derive the equations that are used to extract the gravitational-wave signal.

  9. Pursuit and Synchronization in Hydrodynamic Dipoles

    E-Print Network [OSTI]

    Kanso, Eva

    2015-01-01T23:59:59.000Z

    We study theoretically the behavior of a class of hydrodynamic dipoles. This study is motivated by recent experiments on synthetic and biological swimmers in microfluidic \\textit{Hele-Shaw} type geometries. Under such confinement, a swimmer's hydrodynamic signature is that of a potential source dipole, and the long-range interactions among swimmers are obtained from the superposition of dipole singularities. Here, we recall the equations governing the positions and orientations of interacting asymmetric swimmers in doubly-periodic domains, and focus on the dynamics of swimmer pairs. We obtain two families of `relative equilibria'-type solutions that correspond to pursuit and synchronization of the two swimmers, respectively. Interestingly, the pursuit mode is stable for large tail swimmers whereas the synchronization mode is stable for large head swimmers. These results have profound implications on the collective behavior reported in several recent studies on populations of confined microswimmers.

  10. A fully second order implicit/explicit time integration technique for hydrodynamics plus nonlinear heat conduction problems

    SciTech Connect (OSTI)

    Kadioglu, Samet Y. [Multiphysics Methods Group, Reactor Physics Analysis and Design, Idaho National Laboratory, P.O. Box 1625, MS 3840, Idaho Falls, ID 83415 (United States)], E-mail: Samet.Kadioglu@inl.gov; Knoll, Dana A. [Multiphysics Methods Group, Reactor Physics Analysis and Design, Idaho National Laboratory, P.O. Box 1625, MS 3840, Idaho Falls, ID 83415 (United States)], E-mail: dana.knoll@inl.gov

    2010-05-01T23:59:59.000Z

    We present a fully second order implicit/explicit time integration technique for solving hydrodynamics coupled with nonlinear heat conduction problems. The idea is to hybridize an implicit and an explicit discretization in such a way to achieve second order time convergent calculations. In this scope, the hydrodynamics equations are discretized explicitly making use of the capability of well-understood explicit schemes. On the other hand, the nonlinear heat conduction is solved implicitly. Such methods are often referred to as IMEX methods. The Jacobian-Free Newton Krylov (JFNK) method (e.g. ) is applied to the problem in such a way as to render a nonlinearly iterated IMEX method. We solve three test problems in order to validate the numerical order of the scheme. For each test, we established second order time convergence. We support these numerical results with a modified equation analysis (MEA). The set of equations studied here constitute a base model for radiation hydrodynamics.

  11. Effect of Second-Order Hydrodynamics on Floating Offshore Wind Turbines: Preprint

    SciTech Connect (OSTI)

    Roald, L.; Jonkman, J.; Robertson, A,; Chokani, N.

    2013-07-01T23:59:59.000Z

    Offshore winds are generally stronger and more consistent than winds on land, making the offshore environment attractive for wind energy development. A large part of the offshore wind resource is however located in deep water, where floating turbines are the only economical way of harvesting the energy. The design of offshore floating wind turbines relies on the use of modeling tools that can simulate the entire coupled system behavior. At present, most of these tools include only first-order hydrodynamic theory. However, observations of supposed second-order hydrodynamic responses in wave-tank tests performed by the DeepCwind consortium suggest that second-order effects might be critical. In this paper, the methodology used by the oil and gas industry has been modified to apply to the analysis of floating wind turbines, and is used to assess the effect of second-order hydrodynamics on floating offshore wind turbines. The method relies on combined use of the frequency-domain tool WAMIT and the time-domain tool FAST. The proposed assessment method has been applied to two different floating wind concepts, a spar and a tension-leg-platform (TLP), both supporting the NREL 5-MW baseline wind turbine. Results showing the hydrodynamic forces and motion response for these systems are presented and analysed, and compared to aerodynamic effects.

  12. Consistent description of kinetics and hydrodynamics of dusty plasma

    SciTech Connect (OSTI)

    Markiv, B. [Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii St., 79011 Lviv (Ukraine)] [Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii St., 79011 Lviv (Ukraine); Tokarchuk, M. [Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii St., 79011 Lviv (Ukraine) [Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii St., 79011 Lviv (Ukraine); National University “Lviv Polytechnic,” 12 Bandera St., 79013 Lviv (Ukraine)

    2014-02-15T23:59:59.000Z

    A consistent statistical description of kinetics and hydrodynamics of dusty plasma is proposed based on the Zubarev nonequilibrium statistical operator method. For the case of partial dynamics, the nonequilibrium statistical operator and the generalized transport equations for a consistent description of kinetics of dust particles and hydrodynamics of electrons, ions, and neutral atoms are obtained. In the approximation of weakly nonequilibrium process, a spectrum of collective excitations of dusty plasma is investigated in the hydrodynamic limit.

  13. Standard practice for radiographic examination of advanced aero and turbine materials and components

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2009-01-01T23:59:59.000Z

    1.1 This practice establishes the minimum requirements for radiographic examination of metallic and nonmetallic materials and components used in designated applications such as gas turbine engines and flight structures. 1.2 The requirements in this practice are intended to control the radiographic process to ensure the quality of radiographic images produced for use in designated applications such as gas turbine engines and flight structures; this practice is not intended to establish acceptance criteria for material or components. When examination is performed in accordance with this practice, engineering drawings, specifications or other applicable documents shall indicate the acceptance criteria. 1.3 All areas of this practice may be open to agreement between the cognizant engineering organization and the supplier, or specific direction from the cognizant engineering organization. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the respons...

  14. Real-time spot size camera for pulsed high-energy radiographic machines

    SciTech Connect (OSTI)

    Watson, S.A.

    1993-06-01T23:59:59.000Z

    The focal spot size of an x-ray source is a critical parameter which degrades resolution in a flash radiograph. For best results, a small round focal spot is required. Therefore, a fast and accurate measurement of the spot size is highly desirable to facilitate machine tuning. This paper describes two systems developed for Los Alamos National Laboratory`s Pulsed High-Energy Radiographic Machine Emitting X-rays (PHERMEX) facility. The first uses a CCD camera combined with high-brightness floors, while the second utilizes phosphor storage screens. Other techniques typically record only the line spread function on radiographic film, while systems in this paper measure the more general two-dimensional point-spread function and associated modulation transfer function in real time for shot-to-shot comparison.

  15. Real-time spot size camera for pulsed high-energy radiographic machines

    SciTech Connect (OSTI)

    Watson, S.A.

    1993-01-01T23:59:59.000Z

    The focal spot size of an x-ray source is a critical parameter which degrades resolution in a flash radiograph. For best results, a small round focal spot is required. Therefore, a fast and accurate measurement of the spot size is highly desirable to facilitate machine tuning. This paper describes two systems developed for Los Alamos National Laboratory's Pulsed High-Energy Radiographic Machine Emitting X-rays (PHERMEX) facility. The first uses a CCD camera combined with high-brightness floors, while the second utilizes phosphor storage screens. Other techniques typically record only the line spread function on radiographic film, while systems in this paper measure the more general two-dimensional point-spread function and associated modulation transfer function in real time for shot-to-shot comparison.

  16. Smoothed Particle Hydrodynamics pore-scale simulations of unstable...

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

    experiments using the Pair-Wise Force Smoothed Particle Hydrodynamics (PF-SPH) multiphase flow model. First, we derived analytical expressions relating parameters in the...

  17. Assessing Thermo-Hydrodynamic-Chemical Processes at the Dixie...

    Open Energy Info (EERE)

    Transport Modeling Approach Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Assessing Thermo-Hydrodynamic-Chemical Processes at the Dixie...

  18. Universal holographic hydrodynamics at finite coupling

    E-Print Network [OSTI]

    Alex Buchel; Robert C. Myers; Miguel F. Paulos; Aninda Sinha

    2008-09-12T23:59:59.000Z

    We consider thermal plasmas in a large class of superconformal gauge theories described by a holographic dual geometry of the form $AdS_5\\times M_5$. In particular, we demonstrate that all of the thermodynamic properties and hydrodynamic transport parameters for a large class of superconformal gauge theories exhibit a certain universality to leading order in the inverse 't Hooft coupling and $1/N_c$. In particular, we show that independent of the compactification geometry, the leading corrections are derived from the same five-dimensional effective supergravity action supplemented by a term quartic in the five-dimensional Weyl tensor.

  19. Particle-Based Mesoscale Hydrodynamic Techniques

    E-Print Network [OSTI]

    Hiroshi Noguchi; Norio Kikuchi; Gerhard Gompper

    2006-10-31T23:59:59.000Z

    Dissipative particle dynamics (DPD) and multi-particle collision (MPC) dynamics are powerful tools to study mesoscale hydrodynamic phenomena accompanied by thermal fluctuations. To understand the advantages of these types of mesoscale simulation techniques in more detail, we propose new two methods, which are intermediate between DPD and MPC -- DPD with a multibody thermostat (DPD-MT), and MPC-Langevin dynamics (MPC-LD). The key features are applying a Langevin thermostat to the relative velocities of pairs of particles or multi-particle collisions, and whether or not to employ collision cells. The viscosity of MPC-LD is derived analytically, in very good agreement with the results of numerical simulations.

  20. University of Michigan Hydrodynamics | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlin BaxinUmwelt Management AG UMaAGUnitilMichigan Hydrodynamics Jump to:

  1. University of Minnesota Hydrodynamics | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlin BaxinUmwelt Management AG UMaAGUnitilMichigan Hydrodynamics

  2. Hydrodynamic forces on smooth inclined cylinder in oscillatory flow

    SciTech Connect (OSTI)

    Kang, H.G. [Dalian Univ. of Technology (China)

    1993-12-31T23:59:59.000Z

    The hydrodynamic forces on a smooth inclined circular cylinder exposed to oscillating flow were experimentally investigated at Reynolds number (Re) in the range 40,000--200,000 and Keulegan-Capenter number (Kc) in the interval from 5--40. In the test, Re number and Kc number were varied systematically. The inertia force coefficient (C{sub M}) and the drag force coefficient (C{sub D}) in Morison equation were determined form the measured loads and the water particle kinematics. This analysis uses a modified form of Morison equation since it uses the normal velocity and acceleration. Thus, the applicability of the Cross Flow Principle was assumed. This principle, simply stated, is as follows: the force acting in the direction normal to the axis of a cylinder placed at some oblique angle to the direction of flow is expressed in terms of the normal component of flow only, and the axial component is disregarded. Both total in-line force coefficient (C{sub F}) and transverse force (lift) coefficient (C{sub L}) were analyzed in terms of their maximum and root mean square values. All the in-line and lift force coefficient were given as a functions of Re and Kc number. From this research, it can be seen that the Cross-Flow Principle does not always work well. It seems valid for the total in-line force at high Re and large Kc number; the C{sub M} for {alpha} = 45{degree} is larger and the C{sub D} for {alpha} = 45{degree} is smaller than that for {alpha} = 90{degree} and Re {ge} 80,000. The hydrodynamic force coefficients C{sub D} and C{sub M} for the inclined cylinder are only the functions of oblique angle ({alpha}) and Kc number, but not of the Re number.

  3. anteroposterior chest radiographs: Topics by E-print Network

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

    Cherenkov detector in a beam test. We observed an increase in density at the edge of the aerogel tiles, produced by pin-drying. Makoto Tabata; Ichiro Adachi; Yoshikiyo Hatakeyama;...

  4. Robust model-based detection of the lung field boundaries in portable chest radiographs supported by selective thresholding

    E-Print Network [OSTI]

    Athens, University of

    Robust model-based detection of the lung field boundaries in portable chest radiographs supported of the lung field boundaries in portable chest radiographs supported by selective thresholding D K Iakovidis1-ray misinterpretation rates. This paper presents a novel methodology for the detection of the lung field boundaries

  5. TRANSONIC HYDRODYNAMIC ESCAPE OF HYDROGEN FROM EXTRASOLAR PLANETARY ATMOSPHERES

    E-Print Network [OSTI]

    De Sterck, Hans

    . The model uses a two-dimensional energy depo- sition calculation instead of the single-layer heating planets is investigated using the model. The importance of hydrogen hydrodynamic escape for the longTRANSONIC HYDRODYNAMIC ESCAPE OF HYDROGEN FROM EXTRASOLAR PLANETARY ATMOSPHERES Feng Tian,1, 2 Owen

  6. IUTAM symposium on hydrodynamic diffusion of suspended particles

    SciTech Connect (OSTI)

    Davis, R.H. [ed.

    1995-12-31T23:59:59.000Z

    Hydrodynamic diffusion refers to the fluctuating motion of nonBrownian particles (or droplets or bubbles) which occurs in a dispersion due to multiparticle interactions. For example, in a concentrated sheared suspension, particles do not move along streamlines but instead exhibit fluctuating motions as they tumble around each other. This leads to a net migration of particles down gradients in particle concentration and in shear rate, due to the higher frequency of encounters of a test particle with other particles on the side of the test particle which has higher concentration or shear rate. As another example, suspended particles subject to sedimentation, centrifugation, or fluidization, do not generally move relative to the fluid with a constant velocity, but instead experience diffusion-like fluctuations in velocity due to interactions with neighboring particles and the resulting variation in the microstructure or configuration of the suspended particles. In flowing granular materials, the particles interact through direct collisions or contacts (rather than through the surrounding fluid); these collisions also cause the particles to undergo fluctuating motions characteristic of diffusion processes. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  7. Green's functions and hydrodynamics for isotopic binary diffusion

    E-Print Network [OSTI]

    R. van Zon; E. G. D. Cohen

    2005-08-10T23:59:59.000Z

    We study classical binary fluid mixtures in which densities vary on very short time (ps) and length (nm) scales, such that hydrodynamics does not apply. In a pure fluid with a localized heat pulse the breakdown of hydrodynamics was overcome using Green's functions which connect the initial densities to those at later times. Numerically it appeared that for long times the results from the Green's functions would approach hydrodynamics. In this paper we extend the Green's functions theory to binary mixtures. For the case of isothermal isobaric mutual diffusion in isotopic binary mixtures and ideal binary mixtures, which is easier to handle than heat conduction yet still non-trivial, we show analytically that in the Green's function approach one recovers hydrodynamic behaviour at long time scales provided the system reaches local equilibrium at long times. This is a first step toward giving the Green's function theory a firmer basis because it can for this case be considered as an extension of hydrodynamics.

  8. Analysis of hydrodynamic phenomena in simulant experiments investigating cavity interactions following postulated vessel meltthrough

    SciTech Connect (OSTI)

    Sienicki, J.J.; Spencer, B.W.

    1984-01-01T23:59:59.000Z

    An analysis of hydrodynamic phenomena in simulant experiments examining aspects of ex-vessel material interactions in a PWR reactor cavity following postulated core meltdown and localized breaching of the reactor vessel has been carried out. While previous analyses of the tests examined thresholds for the onset of sweepout of fluid from the cavity, the present analysis considers the progression of specific hydrodynamic phenomena involved in the dispersal process: crater formation due to gas jet impingement, radial wave motion and growth, entrainment and transport of liquid droplets, liquid layer formation due to droplet recombination, fluidization of liquid remaining in the cavity, removal of fluidized liquid droplets from the cavity, and the ultimate removal of the remaining liquid layer within the tunnel passageway. Phenomenological models which may be used to predict the phenomena are presented.

  9. Hydrodynamical simulation of detonations in superbursts. I. The hydrodynamical algorithm and some preliminary one-dimensional results

    E-Print Network [OSTI]

    C. Noel; Y. Busegnies; M. V. Papalexandris; V. Deledicque; A. El Messoudi

    2007-05-18T23:59:59.000Z

    Aims. This work presents a new hydrodynamical algorithm to study astrophysical detonations. A prime motivation of this development is the description of a carbon detonation in conditions relevant to superbursts, which are thought to result from the propagation of a detonation front around the surface of a neutron star in the carbon layer underlying the atmosphere. Methods. The algorithm we have developed is a finite-volume method inspired by the original MUSCL scheme of van Leer (1979). The algorithm is of second-order in the smooth part of the flow and avoids dimensional splitting. It is applied to some test cases, and the time-dependent results are compared to the corresponding steady state solution. Results. Our algorithm proves to be robust to test cases, and is considered to be reliably applicable to astrophysical detonations. The preliminary one-dimensional calculations we have performed demonstrate that the carbon detonation at the surface of a neutron star is a multiscale phenomenon. The length scale of liberation of energy is $10^6$ times smaller than the total reaction length. We show that a multi-resolution approach can be used to solve all the reaction lengths. This result will be very useful in future multi-dimensional simulations. We present also thermodynamical and composition profiles after the passage of a detonation in a pure carbon or mixed carbon-iron layer, in thermodynamical conditions relevant to superbursts in pure helium accretor systems.

  10. Code Differentiation for Hydrodynamic Model Optimization

    SciTech Connect (OSTI)

    Henninger, R.J.; Maudlin, P.J.

    1999-06-27T23:59:59.000Z

    Use of a hydrodynamics code for experimental data fitting purposes (an optimization problem) requires information about how a computed result changes when the model parameters change. These so-called sensitivities provide the gradient that determines the search direction for modifying the parameters to find an optimal result. Here, the authors apply code-based automatic differentiation (AD) techniques applied in the forward and adjoint modes to two problems with 12 parameters to obtain these gradients and compare the computational efficiency and accuracy of the various methods. They fit the pressure trace from a one-dimensional flyer-plate experiment and examine the accuracy for a two-dimensional jet-formation problem. For the flyer-plate experiment, the adjoint mode requires similar or less computer time than the forward methods. Additional parameters will not change the adjoint mode run time appreciably, which is a distinct advantage for this method. Obtaining ''accurate'' sensitivities for the j et problem parameters remains problematic.

  11. Flow stabilization with active hydrodynamic cloaks

    E-Print Network [OSTI]

    Urzhumov, Yaroslav A; 10.1103/PhysRevE.86.056313

    2012-01-01T23:59:59.000Z

    We demonstrate that fluid flow cloaking solutions based on active hydrodynamic metamaterials exist for two-dimensional flows past a cylinder in a wide range of Reynolds numbers, up to approximately 200. Within the framework of the classical Brinkman equation for homogenized porous flow, we demonstrate using two different methods that such cloaked flows can be dynamically stable for $Re$ in the range 5-119. The first, highly efficient, method is based on a linearization of the Brinkman-Navier-Stokes equation and finding the eigenfrequencies of the least stable eigen-perturbations; the second method is a direct, numerical integration in the time domain. We show that, by suppressing the Karman vortex street in the weekly turbulent wake, porous flow cloaks can raise the critical Reynolds number up to about 120, or five times greater than for a bare, uncloaked cylinder.

  12. Assessment of Nuclear Fuels using Radiographic Thickness Measurement Method

    SciTech Connect (OSTI)

    Muhammad Abir; Fahima Islam; Hyoung Koo Lee; Daniel Wachs

    2014-11-01T23:59:59.000Z

    The Convert branch of the National Nuclear Security Administration (NNSA) Global Threat Reduction Initiative (GTRI) focuses on the development of high uranium density fuels for research and test reactors for nonproliferation. This fuel is aimed to convert low density high enriched uranium (HEU) based fuel to high density low enriched uranium (LEU) based fuel for high performance research reactors (HPRR). There are five U.S. reactors that fall under the HPRR category, including: the Massachusetts Institute of Technology Reactor (MITR), the National Bureau of Standards Reactor (NBSR), the Missouri University Research Reactor (UMRR), the Advanced Test Reactor (ATR), and the High Flux Isotope Reactor (HFIR). U-Mo alloy fuel phase in the form of either monolithic or dispersion foil type fuels, such as ATR Full-size In center flux trap Position (AFIP) and Reduced Enrichment for Research and Test Reactor (RERTR), are being designed for this purpose. The fabrication process1 of RERTR is susceptible to introducing a variety of fuel defects. A dependable quality control method is required during fabrication of RERTR miniplates to maintain the allowable design tolerances, therefore evaluating and analytically verifying the fabricated miniplates for maintaining quality standards as well as safety. The purpose of this work is to analyze the thickness of the fabricated RERTR-12 miniplates using non-destructive technique to meet the fuel plate specification for RERTR fuel to be used in the ATR.

  13. Hydrodynamic sweepout thresholds in BWR Mark III reactor cavity interactions

    SciTech Connect (OSTI)

    Spencer, B.W.; Baronowsky, S.P.; Kilsdonk, D.J.

    1984-04-01T23:59:59.000Z

    Simulant-material experiments and related analysis are described which investigated hydrodynamics aspects of ex-vessel interactions following postulated core meltdown with subsequent meltthrough of the vessel lower head and ejection of molten corium from the vessel into the containment region beneath the vessel. Objectives were to examine the possible sweepout of water and corium from the cavity by the steam/H/sub 2/ flow. The dispersal pathways in this containment design include a single manway and four CRD penetrations in the cylindrical pedestal wall connecting to the drywell with a combined cross-sectional area of approx. 10 m/sup 2/. These openings range from 3.4 to 6.3 m in elevation off the concrete floor of the cavity. The experiments were performed using a 1:34 scale mock-up of the RPV/pedestal region. The first tests were quasi-steady tests. Tests were also performed using molten Wood's metal (WM). Some tests were performed with water on the cavity floor, and one test was performed using steel shot. The test results indicated that threshold gas flowrates existed beyond which dispersal of water and/or corium from the cavity can be expected. The predominant dispersal flow regime observed in the experiments involved fluidization of the water or molten WM by the gas flowrate through the system and sweepout of the fluidized liquid droplets as the gas exited the cavity through the openings in the wall. The superficial gas velocity at the onset of water sweepout ranged from 0.87 to 1.04 m/s in the tests which agrees very closely to the calculated fluidization threshold of 0.96 m/s. Application of the fluidization model for prediction of sweepout for the full-size system suggests that sweepout of water and corium can occur if the breach size in the RPV lower head exceeds approx. 10 and 17 cm dia, respectively, for steam blowdown at a vessel initial pressure of 1000 psi.

  14. Simulating Magnetized Laboratory Plasmas with Smoothed Particle Hydrodynamics

    SciTech Connect (OSTI)

    Johnson, J N

    2009-07-02T23:59:59.000Z

    The creation of plasmas in the laboratory continues to generate excitement in the physics community. Despite the best efforts of the intrepid plasma diagnostics community, the dynamics of these plasmas remains a difficult challenge to both the theorist and the experimentalist. This dissertation describes the simulation of strongly magnetized laboratory plasmas with Smoothed Particle Hydrodynamics (SPH), a method born of astrophysics but gaining broad support in the engineering community. We describe the mathematical formulation that best characterizes a strongly magnetized plasma under our circumstances of interest, and we review the SPH method and its application to astrophysical plasmas based on research by Phillips [1], Buerve [2], and Price and Monaghan [3]. Some modifications and extensions to this method are necessary to simulate terrestrial plasmas, such as a treatment of magnetic diffusion based on work by Brookshaw [4] and by Atluri [5]; we describe these changes as we turn our attention toward laboratory experiments. Test problems that verify the method are provided throughout the discussion. Finally, we apply our method to the compression of a magnetized plasma performed by the Compact Toroid Injection eXperiment (CTIX) [6] and show that the experimental results support our computed predictions.

  15. Cosmological Simulations of Galaxy Formation Including Hydrodynamics (hyper-abridged)

    E-Print Network [OSTI]

    F J Summers

    1994-06-02T23:59:59.000Z

    The formation of galaxies in hierarchical cosmogonies is studied using high resolution N-body plus SPH hydrodynamics simulations. The collapse of structure is followed self-consistently from Mpc scale filamentary structures to kpc scale galactic objects. The characteristics and formation processes of the galaxy like objects are studied in detail, along with the aggregation into a poor cluster. Related studies consider the effects of modelling star formation, the reliability of tracing galaxies in simulations, and tests of SPH methods. This submission serves first to notify that the full text and figures of my thesis are available in compressed PostScript form via anonymous ftp from astro.princeton.edu in the directory /summers/thesis (122 files, 19 MB compressed, 65 MB uncompressed). See the README file first. Second, this submission contains the title page, abstract, table of contents, introductory chapter, summary chapter, and references for my thesis. Those who are curious about the work may scan these pages to identify which chapters may be interesting to get via ftp.

  16. BETHE-Hydro: An Arbitrary Lagrangian-Eulerian Multi-dimensional Hydrodynamics Code for Astrophysical Simulations

    E-Print Network [OSTI]

    Jeremiah W. Murphy; Adam Burrows

    2008-07-09T23:59:59.000Z

    In this paper, we describe a new hydrodynamics code for 1D and 2D astrophysical simulations, BETHE-hydro, that uses time-dependent, arbitrary, unstructured grids. The core of the hydrodynamics algorithm is an arbitrary Lagrangian-Eulerian (ALE) approach, in which the gradient and divergence operators are made compatible using the support-operator method. We present 1D and 2D gravity solvers that are finite differenced using the support-operator technique, and the resulting system of linear equations are solved using the tridiagonal method for 1D simulations and an iterative multigrid-preconditioned conjugate-gradient method for 2D simulations. Rotational terms are included for 2D calculations using cylindrical coordinates. We document an incompatibility between a subcell pressure algorithm to suppress hourglass motions and the subcell remapping algorithm and present a modified subcell pressure scheme that avoids this problem. Strengths of this code include a straightforward structure, enabling simple inclusion of additional physics packages, the ability to use a general equation of state, and most importantly, the ability to solve self-gravitating hydrodynamic flows on time-dependent, arbitrary grids. In what follows, we describe in detail the numerical techniques employed and, with a large suite of tests, demonstrate that BETHE-hydro finds accurate solutions with 2$^{nd}$-order convergence.

  17. Initialization of hydrodynamics in relativistic heavy ion collisions with an energy-momentum transport model

    E-Print Network [OSTI]

    V. Yu. Naboka; S. V. Akkelin; Iu. A. Karpenko; Yu. M. Sinyukov

    2015-01-14T23:59:59.000Z

    A key ingredient of hydrodynamical modeling of relativistic heavy ion collisions is thermal initial conditions, an input that is the consequence of a pre-thermal dynamics which is not completely understood yet. In the paper we employ a recently developed energy-momentum transport model of the pre-thermal stage to study influence of the alternative initial states in nucleus-nucleus collisions on flow and energy density distributions of the matter at the starting time of hydrodynamics. In particular, the dependence of the results on isotropic and anisotropic initial states is analyzed. It is found that at the thermalization time the transverse flow is larger and the maximal energy density is higher for the longitudinally squeezed initial momentum distributions. The results are also sensitive to the relaxation time parameter, equation of state at the thermalization time, and transverse profile of initial energy density distribution: Gaussian approximation, Glauber Monte Carlo profiles, etc. Also, test results ensure that the numerical code based on the energy-momentum transport model is capable of providing both averaged and fluctuating initial conditions for the hydrodynamic simulations of relativistic nuclear collisions.

  18. Multigroup radiation hydrodynamics with flux-limited diffusion and adaptive mesh refinement

    E-Print Network [OSTI]

    González, Matthias; Commerçon, Benoît; Masson, Jacques

    2015-01-01T23:59:59.000Z

    Radiative transfer plays a key role in the star formation process. Due to a high computational cost, radiation-hydrodynamics simulations performed up to now have mainly been carried out in the grey approximation. In recent years, multi-frequency radiation-hydrodynamics models have started to emerge, in an attempt to better account for the large variations of opacities as a function of frequency. We wish to develop an efficient multigroup algorithm for the adaptive mesh refinement code RAMSES which is suited to heavy proto-stellar collapse calculations. Due to prohibitive timestep constraints of an explicit radiative transfer method, we constructed a time-implicit solver based on a stabilised bi-conjugate gradient algorithm, and implemented it in RAMSES under the flux-limited diffusion approximation. We present a series of tests which demonstrate the high performance of our scheme in dealing with frequency-dependent radiation-hydrodynamic flows. We also present a preliminary simulation of a three-dimensional p...

  19. Second-Order Accurate Method for Solving Radiation-Hydrodynamics

    E-Print Network [OSTI]

    Edwards, Jarrod Douglas

    2013-11-12T23:59:59.000Z

    Second-order discretization for radiation-hydrodynamics is currently an area of great interest. Second-order methods used to solve the respective single-physics problems often differ fundamentally, making it difficult to combine them in a second...

  20. Characterizing Flow in Oil Reservoir Rock Using Smooth Particle Hydrodynamics

    E-Print Network [OSTI]

    Holmes, David W.

    In this paper, a 3D Smooth Particle Hydrodynamics (SPH) simulator for modeling grain scale fluid flow in porous rock is presented. The versatility of the SPH method has driven its use in increasingly complex areas of flow ...

  1. A GPU Accelerated Smoothed Particle Hydrodynamics Capability For Houdini

    E-Print Network [OSTI]

    Sanford, Mathew

    2012-10-19T23:59:59.000Z

    on the desired result. One common fluid simulation technique is the Smoothed Particle Hydrodynamics (SPH) method. This method is highly parellelizable. I have implemented a method to integrate a Graphics Processor Unit (GPU) accelerated SPH capability into the 3D...

  2. The hydrodynamics of water-walking insects and spiders

    E-Print Network [OSTI]

    Hu, David L., 1979-

    2006-01-01T23:59:59.000Z

    We present a combined experimental and theoretical investigation of the numerous hydrodynamic propulsion mechanisms employed by water-walking arthropods (insects and spiders). In our experimental study, high speed ...

  3. Bulk viscosity and cavitation in boost-invariant hydrodynamic expansion

    E-Print Network [OSTI]

    Rajagopal, Krishna

    We solve second order relativistic hydrodynamics equations for a boost-invariant 1+1-dimensional expanding fluid with an equation of state taken from lattice calculations of the thermodynamics of strongly coupled quark-gluon ...

  4. Hydrodynamics and sediment transport in natural and beneficial use marshes

    E-Print Network [OSTI]

    Kushwaha, Vaishali

    2006-10-30T23:59:59.000Z

    or siltation. The research reported here applies an engineering approach to analysis of tidal creeks in natural and beneficial use marshes of Galveston Bay. The hydrodynamic numerical model, DYNLET, was used to assess circulation in marsh channels. A...

  5. Photoevaporation of protoplanetary discs I: hydrodynamic models

    E-Print Network [OSTI]

    R. D. Alexander; C. J. Clarke; J. E. Pringle

    2006-03-09T23:59:59.000Z

    In this paper we consider the effect of the direct ionizing stellar radiation field on the evolution of protoplanetary discs subject to photoevaporative winds. We suggest that models which combine viscous evolution with photoevaporation of the disc (e.g. Clarke, Gendrin & Sotomayor 2001) incorrectly neglect the direct field after the inner disc has drained, at late times in the evolution. We construct models of the photoevaporative wind produced by the direct field, first using simple analytic arguments and later using detailed numerical hydrodynamics. We find that the wind produced by the direct field at late times is much larger than has previously been assumed, and we show that the mass-loss rate scales as $R_{in}^{1/2}$ (where $R_{in}$ is the radius of the instantaneous inner disc edge). We suggest that this result has important consequences for theories of disc evolution, and go on to consider the effects of this result on disc evolution in detail in a companion paper (Alexander, Clarke & Pringle 2006b).

  6. Energy Gradient Theory of Hydrodynamic Instability

    E-Print Network [OSTI]

    Hua-Shu Dou

    2005-01-29T23:59:59.000Z

    A new universal theory for flow instability and turbulent transition is proposed in this study. Flow instability and turbulence transition have been challenging subjects for fluid dynamics for a century. The critical condition of turbulent transition from theory and experiments differs largely from each other for Poiseuille flows. In this paper, a new mechanism of flow instability and turbulence transition is presented for parallel shear flows and the energy gradient theory of hydrodynamic instability is proposed. It is stated that the total energy gradient in the transverse direction and that in the streamwise direction of the main flow dominate the disturbance amplification or decay. A new dimensionless parameter K for characterizing flow instability is proposed for wall bounded shear flows, which is expressed as the ratio of the energy gradients in the two directions. It is thought that flow instability should first occur at the position of Kmax which may be the most dangerous position. This speculation is confirmed by Nishioka et al's experimental data. Comparison with experimental data for plane Poiseuille flow and pipe Poiseuille flow indicates that the proposed idea is really valid. It is found that the turbulence transition takes place at a critical value of Kmax of about 385 for both plane Poiseuille flow and pipe Poiseuille flow, below which no turbulence will occur regardless the disturbance. More studies show that the theory is also valid for plane Couette flows and Taylor-Couette flows between concentric rotating cylinders.

  7. Hamiltonian Hydrodynamics and Irrotational Binary Inspiral

    E-Print Network [OSTI]

    Charalampos M. Markakis

    2014-10-28T23:59:59.000Z

    Gravitational waves from neutron-star and black-hole binaries carry valuable information on their physical properties and probe physics inaccessible to the laboratory. Although development of black-hole gravitational-wave templates in the past decade has been revolutionary, the corresponding work for double neutron-star systems has lagged. Neutron stars can be well-modelled as simple barotropic fluids during the part of binary inspiral most relevant to gravitational wave astronomy, but the crucial geometric and mathematical consequences of this simplification have remained computationally unexploited. In particular, Carter and Lichnerowicz have described barotropic fluid motion via classical variational principles as conformally geodesic. Moreover, Kelvin's circulation theorem implies that initially irrotational flows remain irrotational. Applied to numerical relativity, these concepts lead to novel Hamiltonian or Hamilton-Jacobi schemes for evolving relativistic fluid flows. Hamiltonian methods can conserve not only flux, but also circulation and symplecticity, and moreover do not require addition of an artificial atmosphere typically required by standard conservative methods. These properties can allow production of high-precision gravitational waveforms at low computational cost. This canonical hydrodynamics approach is applicable to a wide class of problems involving theoretical or computational fluid dynamics.

  8. Vacuum energy: quantum hydrodynamics vs quantum gravity

    E-Print Network [OSTI]

    G. E. Volovik

    2005-09-09T23:59:59.000Z

    We compare quantum hydrodynamics and quantum gravity. They share many common features. In particular, both have quadratic divergences, and both lead to the problem of the vacuum energy, which in the quantum gravity transforms to the cosmological constant problem. We show that in quantum liquids the vacuum energy density is not determined by the quantum zero-point energy of the phonon modes. The energy density of the vacuum is much smaller and is determined by the classical macroscopic parameters of the liquid including the radius of the liquid droplet. In the same manner the cosmological constant is not determined by the zero-point energy of quantum fields. It is much smaller and is determined by the classical macroscopic parameters of the Universe dynamics: the Hubble radius, the Newton constant and the energy density of matter. The same may hold for the Higgs mass problem: the quadratically divergent quantum correction to the Higgs potential mass term is also cancelled by the microscopic (trans-Planckian) degrees of freedom due to thermodynamic stability of the whole quantum vacuum.

  9. Molecular quantum wakes in the hydrodynamic plasma waveguide in air

    SciTech Connect (OSTI)

    Wu Jian; Cai Hua; Zeng Heping [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China); Milchberg, H. M. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States)

    2010-10-15T23:59:59.000Z

    We demonstrate a modulated plasma guiding effect from the molecular alignment wakes in the hydrodynamic plasma waveguide. A properly time-delayed laser pulse can be spatially confined by the hydrodynamic expansion induced plasma waveguide of an advancing femtosecond laser pulse. The spatial confinement can be further strengthened or weakened by following the quantum wakes of the impulsively excited rotational wave packets of the molecules in the plasma waveguide.

  10. A radiographic analysis of the effect of dietary fiber on transit time through the rat large intestine 

    E-Print Network [OSTI]

    Meacher, Mary Melanie

    1986-01-01T23:59:59.000Z

    A RADIOGRAPHIC ANALYSIS OF THE EFFECT OF DIETARY FIBER ON TRANSIT TIME THROUGH THE RAT LARGE INTESTINE A Thesis by MARY MELANIE MEACHER Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 1986 Major Subject. ' Nutrition A RADIOGRAPHIC ANALYSIS OF THE EFFECT OF DIETARY FIBER ON TRANSIT TIME THROUGH THB RAT LARGE INTESTINE A Thesis by MARY MELANIE MEACHER Approved as to style and content by...

  11. X-ray radiographic expansion measurements of isochorically heated thin wire targets

    SciTech Connect (OSTI)

    Hochhaus, D. C. [ExtreMe Matter Institute EMMI, GSI, 64291 Darmstadt (Germany) [ExtreMe Matter Institute EMMI, GSI, 64291 Darmstadt (Germany); Goethe-Universität, 60438 Frankfurt am Main (Germany); Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main (Germany); Aurand, B. [ExtreMe Matter Institute EMMI, GSI, 64291 Darmstadt (Germany) [ExtreMe Matter Institute EMMI, GSI, 64291 Darmstadt (Germany); Johannes Gutenberg-Universität, 55099 Mainz (Germany); Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main (Germany); Basko, M. [ExtreMe Matter Institute EMMI, GSI, 64291 Darmstadt (Germany) [ExtreMe Matter Institute EMMI, GSI, 64291 Darmstadt (Germany); Alikhanov Institute for Theoretical and Experimental Physics, 117218 Moscow (Russian Federation); Ecker, B. [Johannes Gutenberg-Universität, 55099 Mainz (Germany) [Johannes Gutenberg-Universität, 55099 Mainz (Germany); Helmholtz-Institut Jena, 07743 Jena (Germany); Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main (Germany); Kühl, T. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany) [GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Johannes Gutenberg-Universität, 55099 Mainz (Germany); Helmholtz-Institut Jena, 07743 Jena (Germany); ExtreMe Matter Institute EMMI, GSI, 64291 Darmstadt (Germany); Ma, T. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Rosmej, F. [UPMC, UMR7605, LULI, case 128, 4 Place Jussieu, 75252 Paris Cedex 05 (France) [UPMC, UMR7605, LULI, case 128, 4 Place Jussieu, 75252 Paris Cedex 05 (France); Ecole Polytechnique, LULI, PAPD, Route de Saclay, 91128 Palaiseau Cedex (France); Zielbauer, B. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany) [GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Helmholtz-Institut Jena, 07743 Jena (Germany); Neumayer, P. [ExtreMe Matter Institute EMMI, GSI, 64291 Darmstadt (Germany) [ExtreMe Matter Institute EMMI, GSI, 64291 Darmstadt (Germany); Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main (Germany)

    2013-06-15T23:59:59.000Z

    Solid density matter at temperatures ranging from 150 eV to <5 eV has been created by irradiating thin wire targets with high-energy laser pulses at intensities ?10{sup 18}W/cm{sup 2}. Energy deposition and transport of the laser-produced fast electrons are inferred from spatially resolved K{sub ?}-spectroscopy. Time resolved x-ray radiography is employed to image the target mass density up to solid density and proves isochoric heating. The subsequent hydrodynamic evolution of the target is observed for up to 3 ns and is compared to radiation-hydrodynamic simulations. At distances of several hundred micrometers from the laser interaction region, where temperatures of 5–20 eV and small temperature gradients are found, the hydrodynamic evolution of the wire is a near axially symmetric isentropic expansion, and good agreement between simulations and radiography data confirms heating of the wire over hundreds of micrometers.

  12. Dissipative hydrodynamics in 2+1 dimension

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2006-05-25T23:59:59.000Z

    In 2+1 dimension, we have simulated the hydrodynamic evolution of QGP fluid with dissipation due to shear viscosity. Comparison of evolution of ideal and viscous fluid, both initialised under the same conditions e.g. same equilibration time, energy density and velocity profile, reveal that the dissipative fluid evolves slowly, cooling at a slower rate. Cooling get still slower for higher viscosity. The fluid velocities on the otherhand evolve faster in a dissipative fluid than in an ideal fluid. The transverse expansion is also enhanced in dissipative evolution. For the same decoupling temperature, freeze-out surface for a dissipative fluid is more extended than an ideal fluid. Dissipation produces entropy as a result of which particle production is increased. Particle production is increased due to (i) extension of the freeze-out surface and (ii) change of the equilibrium distribution function to a non-equilibrium one, the last effect being prominent at large transverse momentum. Compared to ideal fluid, transverse momentum distribution of pion production is considerably enhanced. Enhancement is more at high $p_T$ than at low $p_T$. Pion production also increases with viscosity, larger the viscosity, more is the pion production. Dissipation also modifies the elliptic flow. Elliptic flow is reduced in viscous dynamics. Also, contrary to ideal dynamics where elliptic flow continues to increase with transverse momentum, in viscous dynamics, elliptic flow tends to saturate at large transverse momentum. The analysis suggest that initial conditions of the hot, dense matter produced in Au+Au collisions at RHIC, as extracted from ideal fluid analysis can be changed significantly if the QGP fluid is viscous.

  13. From Field Theory to the Hydrodynamics of Relativistic Superfluids

    E-Print Network [OSTI]

    Stetina, Stephan

    2015-01-01T23:59:59.000Z

    The hydrodynamic description of a superfluid is usually based on a two-fluid picture. In this thesis, basic properties of such a relativistic two-fluid system are derived from the underlying microscopic physics of a complex scalar quantum field theory. To obtain analytic results of all non-dissipative hydrodynamic quantities in terms of field theoretic variables, calculations are first carried out in a low-temperature and weak-coupling approximation. In a second step, the 2-particle-irreducible formalism is applied: This formalism allows for a numerical evaluation of the hydrodynamic parameters for all temperatures below the critical temperature. In addition, a system of two coupled superfluids is studied. As an application, the velocities of first and second sound in the presence of a superflow are calculated. The results show that first (second) sound evolves from a density (temperature) wave at low temperatures to a temperature (density) wave at high temperatures. This role reversal is investigated for ult...

  14. Conformational Manipulation of DNA in Nanochannels Using Hydrodynamics

    E-Print Network [OSTI]

    Qihao He; Hubert Ranchon; Pascal Carrivain; Yannick Viero; Joris Lacroix; Charline Blatché; Emmanuelle Daran; Jean-Marc Victor; Aurélien Bancaud

    2014-09-01T23:59:59.000Z

    The control over DNA elongation in nanofluidic devices holds great potential for large-scale genomic analysis. So far, the manipulation of DNA in nanochannels has been mostly carried out with electrophoresis and seldom with hydrodynamics, although the physics of soft matter in nanoscale flows has raised considerable interest over the past decade. In this report the migration of DNA is studied in nanochannels of lateral dimension spanning 100 to 500 nm using both actuation principles. We show that the relaxation kinetics are 3-fold slowed down and the extension increases up to 3-fold using hydrodynamics. We propose a model to account for the onset in elongation with the flow, which assumes that DNA response is determined by the shear-driven lift forces mediated by the proximity of the channels' walls. Overall, we suggest that hydrodynamic actuation allows for an improved manipulation of DNA in nanochannels.

  15. Non-decaying hydrodynamic interactions along narrow channels

    E-Print Network [OSTI]

    Misiunas, Karolis; Lauga, Eric; Lister, John R; Keyser, Ulrich F

    2015-01-01T23:59:59.000Z

    Particle-particle interactions are of paramount importance in every multi-body system as they determine the collective behaviour and coupling strength. Many well-known interactions like electro-static, van der Waals or screened Coulomb, decay exponentially or with negative powers of the particle spacing r. Similarly, hydrodynamic interactions between particles undergoing Brownian motion decay as 1/r in bulk, and are assumed to decay quickly in small channels. Such interactions are ubiquitous in biological and technological systems. Here we confine two particles undergoing Brownian motion in narrow, microfluidic channels and study their coupling through hydrodynamic interactions. Our experiments show that, in contrast to expectations from current theoretical understanding, the hydrodynamic particle-particle interactions are long-range and non-decaying in these channels. This new effect is of fundamental importance for the interpretation of experiments where dense mixtures of particles or molecules diffuse thro...

  16. Bulk Viscosity Effects in Event-by-Event Relativistic Hydrodynamics

    E-Print Network [OSTI]

    Jacquelyn Noronha-Hostler; Gabriel S. Denicol; Jorge Noronha; Rone P. G. Andrade; Frederique Grassi

    2013-05-10T23:59:59.000Z

    Bulk viscosity effects on the collective flow harmonics in heavy ion collisions are investigated, on an event by event basis, using a newly developed 2+1 Lagrangian hydrodynamic code named v-USPhydro which implements the Smoothed Particle Hydrodynamics (SPH) algorithm for viscous hydrodynamics. A new formula for the bulk viscous corrections present in the distribution function at freeze-out is derived starting from the Boltzmann equation for multi-hadron species. Bulk viscosity is shown to enhance the collective flow Fourier coefficients from $v_2(p_T)$ to $v_5(p_T)$ when $% p_{T}\\sim 1-3$ GeV even when the bulk viscosity to entropy density ratio, $% \\zeta/s$, is significantly smaller than $1/(4\\pi)$.

  17. Test Automation Test Automation

    E-Print Network [OSTI]

    Mousavi, Mohammad

    Test Automation Test Automation Mohammad Mousavi Eindhoven University of Technology, The Netherlands Software Testing 2013 Mousavi: Test Automation #12;Test Automation Outline Test Automation Mousavi: Test Automation #12;Test Automation Why? Challenges of Manual Testing Test-case design: Choosing inputs

  18. Collective excitations of hydrodynamically coupled driven colloidal particles

    E-Print Network [OSTI]

    Harel Nagar; Yael Roichman

    2014-08-21T23:59:59.000Z

    Two colloidal particles, driven around an optical vortex trap, have been recently shown to pair due to an interplay between hydrodynamic interactions and the curved path they are forced to follow. We demonstrate here, that this pairing interaction can be tuned experimentally, and study its effect on the collective excitations of many particles driven around such an optical trap. We find that even though the system is overdamped, hydrodynamic interactions due to driving give rise to non-decaying excitations with characteristic dispersion relations. The collective excitations of the colloidal ring reflect fluctuations of particle pairs rather than those of single particles.

  19. Second order hydrodynamics for a special class of gravity duals

    SciTech Connect (OSTI)

    Springer, T. [School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2009-04-15T23:59:59.000Z

    The sound mode hydrodynamic dispersion relation is computed up to order q{sup 3} for a class of gravitational duals which includes both Schwarzschild AdS and Dp-brane metrics. The implications for second order transport coefficients are examined within the context of Israel-Stewart theory. These sound mode results are compared with previously known results for the shear mode. This comparison allows one to determine the third order hydrodynamic contributions to the shear mode for the class of metrics considered here.

  20. 3-D HYDRODYNAMIC MODELING IN A GEOSPATIAL FRAMEWORK

    SciTech Connect (OSTI)

    Bollinger, J; Alfred Garrett, A; Larry Koffman, L; David Hayes, D

    2006-08-24T23:59:59.000Z

    3-D hydrodynamic models are used by the Savannah River National Laboratory (SRNL) to simulate the transport of thermal and radionuclide discharges in coastal estuary systems. Development of such models requires accurate bathymetry, coastline, and boundary condition data in conjunction with the ability to rapidly discretize model domains and interpolate the required geospatial data onto the domain. To facilitate rapid and accurate hydrodynamic model development, SRNL has developed a pre- and post-processor application in a geospatial framework to automate the creation of models using existing data. This automated capability allows development of very detailed models to maximize exploitation of available surface water radionuclide sample data and thermal imagery.

  1. Hydrodynamic Shear Rate Regulates Melanoma-Leukocyte Aggregation, Melanoma Adhesion to the Endothelium, and Subsequent Extravasation

    E-Print Network [OSTI]

    Dong, Cheng

    Hydrodynamic Shear Rate Regulates Melanoma-Leukocyte Aggregation, Melanoma Adhesion that polymorphonuclear neutrophils (PMNs) may enhance melanoma adhesion to the endothelium (EC) and subsequent microenvironment within the microcirculation. In this study, effects of hydrodynamic flow on regulating melanoma

  2. Hydrodynamic Shear Rate Regulates Melanoma-Leukocyte Aggregation, Melanoma Adhesion to the Endothelium, and

    E-Print Network [OSTI]

    Simon, Scott I.

    Hydrodynamic Shear Rate Regulates Melanoma-Leukocyte Aggregation, Melanoma Adhesion that polymorphonuclear neutrophils (PMNs) may enhance melanoma adhesion to the endothelium (EC) and subsequent microenvironment within the microcirculation. In this study, effects of hydrodynamic flow on regulating melanoma

  3. Compatible, energy and symmetry preserving 2D Lagrangian hydrodynamics in rz-cylindrical coordinates

    SciTech Connect (OSTI)

    Shashkov, Mikhail [Los Alamos National Laboratory; Wendroff, Burton [Los Alamos National Laboratory; Burton, Donald [Los Alamos National Laboratory; Barlow, A [AWE; Hongbin, Guo [ASU

    2009-01-01T23:59:59.000Z

    We present a new discretization for 2D Lagrangian hydrodynamics in rz geometry (cylindrical coordinates) that is compatible, energy conserving and symmetry preserving. We describe discretization of the basic Lagrangian hydrodynamics equations.

  4. An impulse framework for hydrodynamic force analysis : fish propulsion, water entry of spheres, and marine propellers

    E-Print Network [OSTI]

    Epps, Brenden P

    2010-01-01T23:59:59.000Z

    This thesis presents an impulse framework for analyzing the hydrodynamic forces on bodies in flow. This general theoretical framework is widely applicable, and it is used to address the hydrodynamics of fish propulsion, ...

  5. Onset of superradiant instabilities in the hydrodynamic vortex model

    E-Print Network [OSTI]

    Shahar Hod

    2014-07-30T23:59:59.000Z

    The hydrodynamic vortex, an effective spacetime geometry for propagating sound waves, is studied analytically. In contrast with the familiar Kerr black-hole spacetime, the hydrodynamic vortex model is described by an effective acoustic geometry which has no horizons. However, this acoustic spacetime possesses an ergoregion, a property which it shares with the rotating Kerr spacetime. It has recently been shown numerically that this physical system is linearly unstable due to the superradiant scattering of sound waves in the ergoregion of the effective spacetime. In the present study we use analytical tools in order to explore the onset of these superradiant instabilities which characterize the effective spacetime geometry. In particular, we derive a simple analytical formula which describes the physical properties of the hydrodynamic vortex system in its critical (marginally-stable) state, the state which marks the boundary between stable and unstable fluid configurations. The analytically derived formula is shown to agree with the recently published numerical data for the hydrodynamic vortex system.

  6. New Formulation of Causal Dissipative Hydrodynamics: Shock wave propagation

    E-Print Network [OSTI]

    Ph. Mota; G. S. Denicol; T. Koide; T. Kodama

    2007-01-19T23:59:59.000Z

    The first 3D calculation of shock wave propagation in a homogeneous QGP has been performed within the new formulation of relativistic dissipative hydrodynamics which preserves the causality. We found that the relaxation time plays an important role and also affects the angle of Mach cone.

  7. Sedimentation, Pclet number, and hydrodynamic screening Kiley Benes,1

    E-Print Network [OSTI]

    Tong, Penger

    a is the sphere radius, is the solvent viscosity, g is the accel- eration of gravity, and is the particle. Two functional forms for the sedimentation velocity as a function of particle concen- tration velocity. He assumed i a low particle Reynolds number or the neglect of inertia , ii two- body hydrodynamic

  8. Hydrodynamic analysis of mooring lines based on optical tracking experiments

    E-Print Network [OSTI]

    Yang, Woo Seuk

    2009-05-15T23:59:59.000Z

    Hydrodynamic Force Coefficients.............................................................................11 1.2.2.1. Deterministic Approach .............................................12 1.2.2.2. Stochastic Approach... Page 2.6. Estimation of Force Transfer Coefficients ...........................................50 2.6.1. Fourier Analysis ......................................................................51 2.6.2. Least Square Minimization...

  9. Delta Hydrodynamics and Water Salinity with Future Conditions

    E-Print Network [OSTI]

    Pasternack, Gregory B.

    , Comparing Futures for the Sacramento-San Joaquin Delta, prepared by a team of researchers from the CenterDelta Hydrodynamics and Water Salinity with Future Conditions Technical Appendix C William E of California All rights reserved San Francisco, CA Short sections of text, not to exceed three paragraphs, may

  10. Hydrodynamic model for picosecond propagation of laser-created nanoplasmas

    E-Print Network [OSTI]

    Saxena, Vikrant; Ziaja, Beata; Santra, Robin

    2015-01-01T23:59:59.000Z

    The interaction of a free-electron-laser pulse with a moderate or large size cluster is known to create a quasi-neutral nanoplasma, which then expands on hydrodynamic timescale, i.e., $>1$ ps. To have a better understanding of ion and electron data from experiments derived from laser-irradiated clusters, one needs to simulate cluster dynamics on such long timescales for which the molecular dynamics approach becomes inefficient. We therefore propose a two-step Molecular Dynamics-Hydrodynamic scheme. In the first step we use molecular dynamics code to follow the dynamics of an irradiated cluster until all the photo-excitation and corresponding relaxation processes are finished and a nanoplasma, consisting of ground-state ions and thermalized electrons, is formed. In the second step we perform long-timescale propagation of this nanoplasma with a computationally efficient hydrodynamic approach. In the present paper we examine the feasibility of a hydrodynamic two-fluid approach to follow the expansion of spherica...

  11. Reconstruction of 2D x-ray radiographs at the National Ignition Facility using pinhole tomography (invited)

    SciTech Connect (OSTI)

    Field, J. E., E-mail: field9@llnl.gov; Rygg, J. R.; Barrios, M. A.; Benedetti, L. R.; Döppner, T.; Izumi, N.; Jones, O.; Khan, S. F.; Ma, T.; Nagel, S. R.; Pak, A.; Tommasini, R.; Bradley, D. K.; Town, R. P. J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2014-11-15T23:59:59.000Z

    Two-dimensional radiographs of imploding fusion capsules are obtained at the National Ignition Facility by projection through a pinhole array onto a time-gated framing camera. Parallax among images in the image array makes it possible to distinguish contributions from the capsule and from the backlighter, permitting correction of backlighter non-uniformities within the capsule radiograph. Furthermore, precise determination of the imaging system geometry and implosion velocity enables combination of multiple images to reduce signal-to-noise and discover new capsule features.

  12. Three-Dimensional Hydrodynamic Model for Prediction of Falling Cylinder Through Water Column

    E-Print Network [OSTI]

    Chu, Peter C.

    1 1 Three-Dimensional Hydrodynamic Model for Prediction of Falling Cylinder Through Water Column-coordinate), cylinder's main-axis following coordinate (M-coordinate), and hydrodynamic force following coordinate (F-coordinate system. The hydrodynamic forces (such as the drag and lift forces) and their moments are easily computed

  13. Averaged implicit hydrodynamic model of semiflexible filaments Preethi L. Chandran and Mohammad R. K. Mofrad*

    E-Print Network [OSTI]

    Mofrad, Mohammad R. K.

    , in order to better resolve the drag profiles along the filament. A large part of the hydrodynamic dragAveraged implicit hydrodynamic model of semiflexible filaments Preethi L. Chandran and Mohammad R 2009; published 26 March 2010 We introduce a method to incorporate hydrodynamic interaction in a model

  14. Application of a fiber optic probe to the hydrodynamic study of an industrial fluidized bed furnace

    SciTech Connect (OSTI)

    Saberi, B.; Shakourzadeh, K. [Technical Univ. of Compiegne (France); Militzer, J. [Technical Univ. of Nova Scotia, Halifax, Nova Scotia (Canada)

    1997-12-31T23:59:59.000Z

    A fiber optic probe technique is used to establish the hydrodynamic characteristics of an industrial scale (0.9 m internal diameter and 2.5 m tall) bubbling fluidized bed. This measurement technique allows for the bubbling phenomenon to be studied locally. Bubble parameters such as size, velocity and frequency can be measured with an adequate accuracy. This, however, is not a straight forward procedure, since among other things the shape of the bubble and the position at which fiber intercepts the bubble are unknown. This requires a statistical treatment of the data and the use of a correction factor. A geometrical and statistical analysis of the bubble/probe interactions shows that the correction factor is approximately unitary and thus the bubble size distribution can be obtained directly from the statistical treatment of the results of relatively large number of series of measurements. In addition, sampling rate and sample duration have to be determined as a function of the bubble size and velocity. Several combinations of sampling time and sampling rate have been tested allowing for the best combination of these parameters to be determined. After treatment of the acquired signals, the mean bubble size and velocity were calculated. The results obtained were compared to the measured expansion of the bed and the overall gas flow rate. This confirmed the accuracy of the measurements and the usefulness of this technique to establish the hydrodynamics of bubbling fluidized beds.

  15. Dose impact in radiographic lung injury following lung SBRT: Statistical analysis and geometric interpretation

    SciTech Connect (OSTI)

    Yu, Victoria; Kishan, Amar U.; Cao, Minsong; Low, Daniel; Lee, Percy; Ruan, Dan, E-mail: druan@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90024 (United States)] [Department of Radiation Oncology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90024 (United States)

    2014-03-15T23:59:59.000Z

    Purpose: To demonstrate a new method of evaluating dose response of treatment-induced lung radiographic injury post-SBRT (stereotactic body radiotherapy) treatment and the discovery of bimodal dose behavior within clinically identified injury volumes. Methods: Follow-up CT scans at 3, 6, and 12 months were acquired from 24 patients treated with SBRT for stage-1 primary lung cancers or oligometastic lesions. Injury regions in these scans were propagated to the planning CT coordinates by performing deformable registration of the follow-ups to the planning CTs. A bimodal behavior was repeatedly observed from the probability distribution for dose values within the deformed injury regions. Based on a mixture-Gaussian assumption, an Expectation-Maximization (EM) algorithm was used to obtain characteristic parameters for such distribution. Geometric analysis was performed to interpret such parameters and infer the critical dose level that is potentially inductive of post-SBRT lung injury. Results: The Gaussian mixture obtained from the EM algorithm closely approximates the empirical dose histogram within the injury volume with good consistency. The average Kullback-Leibler divergence values between the empirical differential dose volume histogram and the EM-obtained Gaussian mixture distribution were calculated to be 0.069, 0.063, and 0.092 for the 3, 6, and 12 month follow-up groups, respectively. The lower Gaussian component was located at approximately 70% prescription dose (35 Gy) for all three follow-up time points. The higher Gaussian component, contributed by the dose received by planning target volume, was located at around 107% of the prescription dose. Geometrical analysis suggests the mean of the lower Gaussian component, located at 35 Gy, as a possible indicator for a critical dose that induces lung injury after SBRT. Conclusions: An innovative and improved method for analyzing the correspondence between lung radiographic injury and SBRT treatment dose has been demonstrated. Bimodal behavior was observed in the dose distribution of lung injury after SBRT. Novel statistical and geometrical analysis has shown that the systematically quantified low-dose peak at approximately 35 Gy, or 70% prescription dose, is a good indication of a critical dose for injury. The determined critical dose of 35 Gy resembles the critical dose volume limit of 30 Gy for ipsilateral bronchus in RTOG 0618 and results from previous studies. The authors seek to further extend this improved analysis method to a larger cohort to better understand the interpatient variation in radiographic lung injury dose response post-SBRT.

  16. X-ray radiographic technique for measuring density uniformity of silica aerogel

    E-Print Network [OSTI]

    Makoto Tabata; Yoshikiyo Hatakeyama; Ichiro Adachi; Takeshi Morita; Keiko Nishikawa

    2012-12-14T23:59:59.000Z

    This paper proposes a new X-ray radiographic technique for measuring density uniformity of silica aerogels used as radiator in proximity-focusing ring-imaging Cherenkov detectors. To obtain high performance in a large-area detector, a key characteristic of radiator is the density (i.e. refractive index) uniformity of an individual aerogel monolith. At a refractive index of n = 1.05, our requirement for the refractive index uniformity in the transverse plane direction of an aerogel tile is |\\delta (n - 1)/(n - 1)| aerogels from a trial production and that of Panasonic products (SP-50) as a reference, and to confirm they have sufficient density uniformity within \\pm 1% along the transverse plane direction. The measurement results show that the proposed technique can quantitatively estimate the density uniformity of aerogels.

  17. X-ray radiographic technique for measuring density uniformity of silica aerogel

    E-Print Network [OSTI]

    Tabata, Makoto; Adachi, Ichiro; Morita, Takeshi; Nishikawa, Keiko; 10.1016/j.nima.2012.09.001

    2012-01-01T23:59:59.000Z

    This paper proposes a new X-ray radiographic technique for measuring density uniformity of silica aerogels used as radiator in proximity-focusing ring-imaging Cherenkov detectors. To obtain high performance in a large-area detector, a key characteristic of radiator is the density (i.e. refractive index) uniformity of an individual aerogel monolith. At a refractive index of n = 1.05, our requirement for the refractive index uniformity in the transverse plane direction of an aerogel tile is |\\delta (n - 1)/(n - 1)| aerogels from a trial production and that of Panasonic products (SP-50) as a reference, and to confirm they have sufficient density uniformity within \\pm 1% along the transverse plane direction. The measurement results show that the proposed technique can quantitatively estimate the density uniformity of aerogels.

  18. Galaxies that Shine: radiation-hydrodynamical simulations of disk galaxies

    E-Print Network [OSTI]

    Rosdahl, Joakim; Teyssier, Romain; Agertz, Oscar

    2015-01-01T23:59:59.000Z

    Radiation feedback is typically implemented using subgrid recipes in hydrodynamical simulations of galaxies. Very little work has so far been performed using radiation-hydrodynamics (RHD), and there is no consensus on the importance of radiation feedback in galaxy evolution. We present RHD simulations of isolated galaxy disks of different masses with a resolution of 18 pc. Besides accounting for supernova feedback, our simulations are the first galaxy-scale simulations to include RHD treatments of photo-ionisation heating and radiation pressure, from both direct optical/UV radiation and multi-scattered, re-processed infrared (IR) radiation. Photo-heating smooths and thickens the disks and suppresses star formation about as much as the inclusion of ("thermal dump") supernova feedback does. These effects decrease with galaxy mass and are mainly due to the prevention of the formation of dense clouds, as opposed to their destruction. Radiation pressure, whether from direct or IR radiation, has little effect, but ...

  19. Numerical integration of thermal noise in relativistic hydrodynamics

    E-Print Network [OSTI]

    Clint Young

    2013-06-03T23:59:59.000Z

    Thermal fluctuations affect the dynamics of systems near critical points, the evolution of the early universe, and two-particle correlations in heavy-ion collisions. For the latter, numerical simulations of nearly-ideal, relativistic fluids are necessary. The correlation functions of noise in relativistic fluids are calculated, stochastic integration of the noise in 3+1-dimensional viscous hydrodynamics is implemented, and the effect of noise on observables in heavy-ion collisions is discussed. Thermal fluctuations will cause significant variance in the event-by-event distributions of integrated v2 while changing average values even when using the same initial conditions, suggesting that including thermal noise will lead to refitting of the hydrodynamical parameters with implications for understanding the physics of hot QCD.

  20. Enhanced Heat Flow in the Hydrodynamic Collisionless Regime

    SciTech Connect (OSTI)

    Meppelink, R.; Rooij, R. van; Vogels, J. M.; Straten, P. van der [Atom Optics and Ultrafast Dynamics, Utrecht University, P.O. Box 80000, 3508 TA Utrecht (Netherlands)

    2009-08-28T23:59:59.000Z

    We study the heat conduction of a cold, thermal cloud in a highly asymmetric trap. The cloud is axially hydrodynamic, but due to the asymmetric trap radially collisionless. By locally heating the cloud we excite a thermal dipole mode and measure its oscillation frequency and damping rate. We find an unexpectedly large heat conduction compared to the homogeneous case. The enhanced heat conduction in this regime is partially caused by atoms with a high angular momentum spiraling in trajectories around the core of the cloud. Since atoms in these trajectories are almost collisionless they strongly contribute to the heat transfer. We observe a second, oscillating hydrodynamic mode, which we identify as a standing wave sound mode.

  1. Hydrodynamic model of Fukushima-Daiichi NPP Industrial site flooding

    E-Print Network [OSTI]

    Vaschenko, V N; Gerasimenko, T V; Vachev, B

    2014-01-01T23:59:59.000Z

    While the Fukushima-Daiichi was designed and constructed the maximal tsunami height estimate was about 3 m based on analysis of statistical data including Chile earthquake in 1960. The NPP project industrial site height was 10 m. The further deterministic estimates TPCO-JSCE confirmed the impossibility of the industrial site flooding by a tsunami and therefore confirmed ecological safety of the NPP. However, as a result of beyond design earthquake of 11 March 2011 the tsunami height at the shore near the Fukushima-Daiichi NPP reached 15 m. This led to flooding and severe emergencies having catastrophic environmental consequences. This paper proposes hydrodynamic model of tsunami emerging and traveling based on conservative assumptions. The possibility of a tsunami wave reaching 15 m height at the Fukushima-Daiichi NPP shore was confirmed for deduced hydrodynamic resistance coefficient of 1.8. According to the model developed a possibility of flooding is determined not only by the industrial site height, magni...

  2. Hydrodynamic instabilities in beryllium targets for the National Ignition Facility

    SciTech Connect (OSTI)

    Yi, S. A., E-mail: austinyi@lanl.gov; Simakov, A. N.; Wilson, D. C.; Olson, R. E.; Kline, J. L.; Batha, S. H. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545 (United States); Clark, D. S.; Hammel, B. A.; Milovich, J. L.; Salmonson, J. D.; Kozioziemski, B. J. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States)

    2014-09-15T23:59:59.000Z

    Beryllium ablators offer higher ablation velocity, rate, and pressure than their carbon-based counterparts, with the potential to increase the probability of achieving ignition at the National Ignition Facility (NIF) [E. I. Moses et al., Phys. Plasmas 16, 041006 (2009)]. We present here a detailed hydrodynamic stability analysis of low (NIF Revision 6.1) and high adiabat NIF beryllium target designs. Our targets are optimized to fully utilize the advantages of beryllium in order to suppress the growth of hydrodynamic instabilities. This results in an implosion that resists breakup of the capsule, and simultaneously minimizes the amount of ablator material mixed into the fuel. We quantify the improvement in stability of beryllium targets relative to plastic ones, and show that a low adiabat beryllium capsule can be at least as stable at the ablation front as a high adiabat plastic target.

  3. Porous Superhydrophobic Membranes: Hydrodynamic Anomaly in Oscillating Flows

    E-Print Network [OSTI]

    Rajauria, Sukumar; Lawall, J; Yakhot, Victor; Ekinci, Kamil L

    2011-01-01T23:59:59.000Z

    We have fabricated and characterized a novel superhydrophobic system, a mesh-like porous superhydrophobic membrane with solid area fraction $\\Phi_s$, which can maintain intimate contact with outside air and water reservoirs simultaneously. Oscillatory hydrodynamic measurements on porous superhydrophobic membranes as a function of $\\Phi_s$ reveal surprising effects. The hydrodynamic mass oscillating in-phase with the membranes stays constant for $0.9\\le\\Phi_s\\le1$, but drops precipitously for $\\Phi_s < 0.9$. The viscous friction shows a similar drop after a slow initial decrease proportional to $\\Phi_s$. We attribute these effects to the percolation of a stable Knudsen layer of air at the interface.

  4. Porous Superhydrophobic Membranes: Hydrodynamic Anomaly in Oscillating Flows

    E-Print Network [OSTI]

    Sukumar Rajauria; O. Ozsun; J. Lawall; Victor Yakhot; Kamil L. Ekinci

    2011-08-05T23:59:59.000Z

    We have fabricated and characterized a novel superhydrophobic system, a mesh-like porous superhydrophobic membrane with solid area fraction $\\Phi_s$, which can maintain intimate contact with outside air and water reservoirs simultaneously. Oscillatory hydrodynamic measurements on porous superhydrophobic membranes as a function of $\\Phi_s$ reveal surprising effects. The hydrodynamic mass oscillating in-phase with the membranes stays constant for $0.9\\le\\Phi_s\\le1$, but drops precipitously for $\\Phi_s < 0.9$. The viscous friction shows a similar drop after a slow initial decrease proportional to $\\Phi_s$. We attribute these effects to the percolation of a stable Knudsen layer of air at the interface.

  5. Hydrodynamic analogy of production decline for Devonian shale wells

    SciTech Connect (OSTI)

    Pulle, C.V.

    1982-01-01T23:59:59.000Z

    Several studies on production decline curves have shown that an exponential or hyperbolic curve adequately fits production decline data for Devonian shale wells. Attempts to characterize the production decline based on open flows, rock pressures, and specific shale production mechanisms have also been made. This paper seeks to provide a genesis of the decline curves with the use of a simple hydrodynamic analogy. Some physical factors critical to well productivity are also examined. 4 refs.

  6. Skew and twist resistant hydrodynamic rotary shaft seal

    DOE Patents [OSTI]

    Dietle, Lannie (Sugar Land, TX); Kalsi, Manmohan Singh (Houston, TX)

    1999-01-01T23:59:59.000Z

    A hydrodynamically lubricated squeeze packing type rotary shaft seal suitable for lubricant retention and environmental exclusion which incorporates one or more resilient protuberances which and cooperate with the gland walls to hold the seal straight in its installation groove in unpressurized and low pressure lubricant retention applications thereby preventing skew-induced wear caused by impingement of abrasive contaminants present in the environment, and which also serve as radial bearings to prevent tipping of the seal within its installation gland.

  7. Skew and twist resistant hydrodynamic rotary shaft seal

    DOE Patents [OSTI]

    Dietle, L.; Kalsi, M.S.

    1999-02-23T23:59:59.000Z

    A hydrodynamically lubricated squeeze packing type rotary shaft seal suitable for lubricant retention and environmental exclusion which incorporates one or more resilient protuberances which cooperate with the gland walls to hold the seal straight in its installation groove in unpressurized and low pressure lubricant retention applications thereby preventing skew-induced wear caused by impingement of abrasive contaminants present in the environment, and which also serve as radial bearings to prevent tipping of the seal within its installation gland. 14 figs.

  8. Variational Principle of Hydrodynamics and Quantization by Stochastic Process

    E-Print Network [OSTI]

    T. Kodama; T. Koide

    2015-01-05T23:59:59.000Z

    The well-known hydrodynamical representation of the Schr\\"{o}dinger equation is reformulated by extending the idea of Nelson-Yasue's stochastic variational method. The fluid flow is composed by the two stochastic processes from the past and the future, which are unified naturally by the principle of maximum entropy. We show that this formulation is easily applicable to the quantization of scalar fields.

  9. A new algorithm for modelling photoionising radiation in smoothed particle hydrodynamics

    E-Print Network [OSTI]

    James Dale; Barbara Ercolano; Cathie Clarke

    2007-05-23T23:59:59.000Z

    We present a new fast algorithm which allows the simulation of ionising radiation emitted from point sources to be included in high-resolution three-dimensional smoothed particle hydrodynamics simulations of star cluster formation. We employ a Str\\"omgren volume technique in which we use the densities of particles near the line-of-sight between the source and a given target particle to locate the ionisation front in the direction of the target. Along with one--dimensional tests, we present fully three--dimensional comparisons of our code with the three--dimensional Monte-Carlo radiative transfer code, MOCASSIN, and show that we achieve good agreement, even in the case of highly complex density fields.

  10. Redesign of turbine-pump impeller and diffuser using hydrodynamic design techniques. Final report

    SciTech Connect (OSTI)

    Hamrick, J.T.

    1980-04-01T23:59:59.000Z

    It is indicated that in 1976 the average operating efficiency of well irrigation pumps in the US, including losses in the column pipe and line shaft, was 55.5%, but information is presented to show that losses in a pumping system can be reduced and that it is possible to reach a goal of 82% system efficiency. Hydrodynamic design methods which are used to analyze and modify a commercially available pump are presented. The results of tests with the pump are presented for which delivery losses were reduced by means of a packer at the pump and for which line shaft losses were reduced by means of a high strength line shaft. Methods of designing pumps that have a broader high efficiency range are explored, and a design approach for doing so is presented. The method was not evaluated experimentally. (MCW)

  11. An efficient approach to unstructured mesh hydrodynamics on the cell broadband engine (u)

    SciTech Connect (OSTI)

    Ferenbaugh, Charles R [Los Alamos National Laboratory

    2010-12-14T23:59:59.000Z

    Unstructured mesh physics for the Cell Broadband Engine (CBE) has received little or no attention to date, largely because the CBE architecture poses particular challenges for unstructured mesh algorithms. SPU memory management strategies such as data preloading cannot be applied to the irregular memory storage patterns of unstructured meshes; and the SPU vector instruction set does not support the indirect addressing needed by connectivity arrays. This paper presents an approach to unstructured mesh physics that addresses these challenges, by creating a new mesh data structure and reorganizing code to give efficient CBE performance. The approach is demonstrated on the FLAG production hydrodynamics code using standard test problems, and results show an average speedup of more than 5x over the original code.

  12. A multiblob approach to colloidal hydrodynamics with inherent lubrication

    E-Print Network [OSTI]

    Adolfo Vázquez-Quesada; Florencio Balboa Usabiaga; Rafael Delgado-Buscalioni

    2014-07-23T23:59:59.000Z

    This work presents an intermediate resolution model of the hydrodynamics of colloidal particles based on a mixed Eulerian-Lagrangian formulation. The particle is constructed with a small set of overlapping Peskin's Immersed Boundary kernels (blobs) which are held together by springs to build up a particle impenetrable core. Here, we used 12 blobs placed in the vertexes of an icosahedron with an extra one in its center. Although the particle surface is not explicitly resolved, we show that the short-distance hydrodynamic responses (flow profiles, translational and rotational mobilities, lubrication, etc) agree with spherical colloids and provide consistent effective radii. A remarkable property of the present multiblob model is that it naturally presents a "divergent" lubrication force at finite inter-particle distance. This permits to resolve the large viscosity increase at dense colloidal volume fractions. The intermediate resolution model is able to recover highly non-trivial (many-body) hydrodynamics using small particles whose radii are similar to the grid size $h$ (in the range $[1.6-3.2]\\,h$). Considering that the cost of the embedding fluid phase scales like the cube of the particle radius, this result brings about a significant computational speed-up. Our code Fluam works in Graphics Processor Units (GPU's) and uses Fast Fourier Transform for the Poisson solver, which further improves its efficiency.

  13. From Field Theory to the Hydrodynamics of Relativistic Superfluids

    E-Print Network [OSTI]

    Stephan Stetina

    2015-01-31T23:59:59.000Z

    The hydrodynamic description of a superfluid is usually based on a two-fluid picture. In this thesis, basic properties of such a relativistic two-fluid system are derived from the underlying microscopic physics of a complex scalar quantum field theory. To obtain analytic results of all non-dissipative hydrodynamic quantities in terms of field theoretic variables, calculations are first carried out in a low-temperature and weak-coupling approximation. In a second step, the 2-particle-irreducible formalism is applied: This formalism allows for a numerical evaluation of the hydrodynamic parameters for all temperatures below the critical temperature. In addition, a system of two coupled superfluids is studied. As an application, the velocities of first and second sound in the presence of a superflow are calculated. The results show that first (second) sound evolves from a density (temperature) wave at low temperatures to a temperature (density) wave at high temperatures. This role reversal is investigated for ultra-relativistic and near-nonrelativistic systems for zero and nonzero superflow. The studies carried out in this thesis are of a very general nature as one does not have to specify the system for which the microscopic field theory is an effective description. As a particular example, superfluidity in dense quark and nuclear matter in compact stars are discussed.

  14. Assessment of Tidal Energy Removal Impacts on Physical Systems: Development of MHK Module and Analysis of Effects on Hydrodynamics

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Wang, Taiping

    2011-09-01T23:59:59.000Z

    In this report we describe (1) the development, test, and validation of the marine hydrokinetic energy scheme in a three-dimensional coastal ocean model (FVCOM); and (2) the sensitivity analysis of effects of marine hydrokinetic energy configurations on power extraction and volume flux in a coastal bay. Submittal of this report completes the work on Task 2.1.2, Effects of Physical Systems, Subtask 2.1.2.1, Hydrodynamics and Subtask 2.1.2.3, Screening Analysis, for fiscal year 2011 of the Environmental Effects of Marine and Hydrokinetic Energy project.

  15. Global existence and semiclassical limit for quantum hydrodynamic equations with viscosity and heat conduction

    E-Print Network [OSTI]

    Xueke Pu; Boling Guo

    2015-04-21T23:59:59.000Z

    The hydrodynamic equations with quantum effects are studied in this paper. First we establish the global existence of smooth solutions with small initial data and then in the second part, we establish the convergence of the solutions of the quantum hydrodynamic equations to those of the classical hydrodynamic equations. The energy equation is considered in this paper, which added new difficulties to the energy estimates, especially to the selection of the appropriate Sobolev spaces.

  16. AXIS: An instrument for imaging Compton radiographs using the Advanced Radiography Capability on the NIF

    SciTech Connect (OSTI)

    Hall, G. N., E-mail: hall98@llnl.gov; Izumi, N.; Tommasini, R.; Carpenter, A. C.; Palmer, N. E.; Zacharias, R.; Felker, B.; Holder, J. P.; Allen, F. V.; Bell, P. M.; Bradley, D.; Montesanti, R.; Landen, O. L. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550 (United States)

    2014-11-15T23:59:59.000Z

    Compton radiography is an important diagnostic for Inertial Confinement Fusion (ICF), as it provides a means to measure the density and asymmetries of the DT fuel in an ICF capsule near the time of peak compression. The AXIS instrument (ARC (Advanced Radiography Capability) X-ray Imaging System) is a gated detector in development for the National Ignition Facility (NIF), and will initially be capable of recording two Compton radiographs during a single NIF shot. The principal reason for the development of AXIS is the requirement for significantly improved detection quantum efficiency (DQE) at high x-ray energies. AXIS will be the detector for Compton radiography driven by the ARC laser, which will be used to produce Bremsstrahlung X-ray backlighter sources over the range of 50 keV–200 keV for this purpose. It is expected that AXIS will be capable of recording these high-energy x-rays with a DQE several times greater than other X-ray cameras at NIF, as well as providing a much larger field of view of the imploded capsule. AXIS will therefore provide an image with larger signal-to-noise that will allow the density and distribution of the compressed DT fuel to be measured with significantly greater accuracy as ICF experiments are tuned for ignition.

  17. A flat-cathode thermionic injector for the PHERMEX Radiographic Facility

    SciTech Connect (OSTI)

    Kauppila, T.; Builta, L.; Burns, M.; Gregory, W.; Honaberger, D.; Watson, S. (Los Alamos National Lab., NM (United States)); Hughes, T. (Mission Research Corp., Albuquerque, NM (United States))

    1993-01-01T23:59:59.000Z

    The PHERMEX (Pulsed High-Energy Radiographic Machine Emitting X-rays) standing-wave linear accelerator is a high-current electron beam generator used for flash-radiography. An improved electron gun has been designed employing a flat-thermionic cathode to replace the existing Pierce-geometry gun. The flat cathode yields increased current with the same applied voltage and cathode area as the Pierce gun. The ISIS code simulations indicate a beam current of 1.5 kA at 600 kV. The new geometry also reduces the probability for high voltage breakdown in the A-K gap. A reentrant magnet captures the expanding electron beam and a bucking coil nulls cathode-tinge field. A third coil is used to optimize the extraction field profile and reduce the effect of nonlinear space charge on the beam emittance. Time-resolved measurements of beam current and voltage have been made. In addition, a streak camera was used to measure beam emittance and spatial profile. Comparisons of measurements with simulations are presented.

  18. A flat-cathode thermionic injector for the PHERMEX Radiographic Facility

    SciTech Connect (OSTI)

    Kauppila, T.; Builta, L.; Burns, M.; Gregory, W.; Honaberger, D.; Watson, S. [Los Alamos National Lab., NM (United States); Hughes, T. [Mission Research Corp., Albuquerque, NM (United States)

    1993-06-01T23:59:59.000Z

    The PHERMEX (Pulsed High-Energy Radiographic Machine Emitting X-rays) standing-wave linear accelerator is a high-current electron beam generator used for flash-radiography. An improved electron gun has been designed employing a flat-thermionic cathode to replace the existing Pierce-geometry gun. The flat cathode yields increased current with the same applied voltage and cathode area as the Pierce gun. The ISIS code simulations indicate a beam current of 1.5 kA at 600 kV. The new geometry also reduces the probability for high voltage breakdown in the A-K gap. A reentrant magnet captures the expanding electron beam and a bucking coil nulls cathode-tinge field. A third coil is used to optimize the extraction field profile and reduce the effect of nonlinear space charge on the beam emittance. Time-resolved measurements of beam current and voltage have been made. In addition, a streak camera was used to measure beam emittance and spatial profile. Comparisons of measurements with simulations are presented.

  19. Hydrodynamic and Ecological Assessment of Nearshore Restoration: A Modeling Study

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Sobocinski, Kathryn L.; Heatwole, Danelle W.; Khangaonkar, Tarang; Thom, Ronald M.; Fuller, Roger

    2010-04-10T23:59:59.000Z

    Along the Pacific Northwest coast, much of the estuarine habitat has been diked over the last century for agricultural land use, residential and commercial development, and transportation corridors. As a result, many of the ecological processes and functions have been disrupted. To protect coastal habitats that are vital to aquatic species, many restoration projects are currently underway to restore the estuarine and coastal ecosystems through dike breaches, setbacks, and removals. Information on physical processes and hydrodynamic conditions are critical for the assessment of the success of restoration actions. Restoration of a 160- acre property at the mouth of the Stillaguamish River in Puget Sound has been proposed. The goal is to restore native tidal habitats and estuary-scale ecological processes by removing the dike. In this study, a three-dimensional hydrodynamic model was developed for the Stillaguamish River estuary to simulate estuarine processes. The model was calibrated to observed tide, current, and salinity data for existing conditions and applied to simulate the hydrodynamic responses to two restoration alternatives. Responses were evaluated at the scale of the restoration footprint. Model data was combined with biophysical data to predict habitat responses at the site. Results showed that the proposed dike removal would result in desired tidal flushing and conditions that would support four habitat types on the restoration footprint. At the estuary scale, restoration would substantially increase the proportion of area flushed with freshwater (< 5 ppt) at flood tide. Potential implications of predicted changes in salinity and flow dynamics are discussed relative to the distribution of tidal marsh habitat.

  20. Chemo -- Dynamical evolution of disk galaxies, smoothed particles hydrodynamics approach

    E-Print Network [OSTI]

    Peter Berczik

    1998-10-20T23:59:59.000Z

    A new Chemo -- Dynamical Smoothed Particle Hydrodynamic (CD -- SPH) code is presented. The disk galaxy is described as a multi -- fragmented gas and star system, embedded into the cold dark matter halo. The star formation (SF) process, SNII, SNIa and PN events as well as chemical enrichment of gas have been considered within the framework of standard SPH model. Using this model we try to describe the dynamical and chemical evolution of triaxial disk -- like galaxies. It is found that such approach provides a realistic description of the process of formation, chemical and dynamical evolution of disk galaxies over the cosmological timescale.

  1. SPLASH: An interactive visualisation tool for Smoothed Particle Hydrodynamics simulations

    E-Print Network [OSTI]

    Daniel J. Price

    2007-09-06T23:59:59.000Z

    This paper presents SPLASH, a publicly available interactive visualisation tool for Smoothed Particle Hydrodynamics (SPH) simulations. Visualisation of SPH data is more complicated than for grid-based codes because the data is defined on a set of irregular points and therefore requires a mapping procedure to a two dimensional pixel array. This means that, in practise, many authors simply produce particle plots which offer a rather crude representation of the simulation output. Here we describe the techniques and algorithms which are utilised in SPLASH in order to provide the user with a fast, interactive and meaningful visualisation of one, two and three dimensional SPH results.

  2. Role of Brownian Motion Hydrodynamics on Nanofluid Thermal Conductivity

    SciTech Connect (OSTI)

    W Evans, J Fish, P Keblinski

    2005-11-14T23:59:59.000Z

    We use a simple kinetic theory based analysis of heat flow in fluid suspensions of solid nanoparticles (nanofluids) to demonstrate that the hydrodynamics effects associated with Brownian motion have a minor effect on the thermal conductivity of the nanofluid. Our conjecture is supported by the results of molecular dynamics simulations of heat flow in a model nanofluid with well-dispersed particles. Our findings are consistent with the predictions of the effective medium theory as well as with recent experimental results on well dispersed metal nanoparticle suspensions.

  3. Hydrodynamic Modes of a holographic $p-$ wave superfluid

    E-Print Network [OSTI]

    Raul E. Arias; Ignacio Salazar Landea

    2014-11-04T23:59:59.000Z

    In this work we analyze the hydrodynamics of a $p-$ wave superfluid on its strongly coupled regime by considering its holographic description. We obtain the poles of the retarded Green function through the computation of the quasi-normal modes of the dual AdS black hole background finding diffusive, pseudo-diffusive and sound modes. For the sound modes we compute the speed of sound and its attenuation as function of the temperature. For the diffusive and pseudo-diffusive modes we find that they acquire a non-zero real part at certain finite momentum.

  4. Electron magneto-hydrodynamic waves bounded by magnetic bubble

    SciTech Connect (OSTI)

    Anitha, V. P.; Sharma, D.; Banerjee, S. P.; Mattoo, S. K. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2012-08-15T23:59:59.000Z

    The propagation of electron magneto-hydrodynamic (EMHD) waves is studied experimentally in a 3-dimensional region of low magnetic field surrounded by stronger magnetic field at its boundaries. We report observations where bounded left hand polarized Helicon like EMHD waves are excited, localized in the region of low magnetic field due to the boundary effects generated by growing strengths of the ambient magnetic field rather than a conducting or dielectric material boundary. An analytical model is developed to include the effects of radially nonuniform magnetic field in the wave propagation. The bounded solutions are compared with the experimentally obtained radial wave magnetic field profiles explaining the observed localized propagation of waves.

  5. Skew And Twist Resistant Hydrodynamic Rotary Shaft Seal

    DOE Patents [OSTI]

    Dietle, Lannie (Sugar Land, TX); Kalsi, Manmohan Singh (Houston, TX)

    2000-03-14T23:59:59.000Z

    A hydrodynamically lubricated squeeze packing type rotary shaft seal suitable for lubricant retention and environmental exclusion which incorporates one or more resilient protuberances which and cooperate with the gland walls to hold the seal straight in its installation groove in unpressurized and low pressure lubricant retention applications thereby preventing skew-induced wear caused by impingement of abrasive contaminants present in the environment, and which also serve as radial bearings to prevent tipping of the seal within its installation gland. Compared to prior art, this invention provides a dramatic reduction of seal and shaft wear in abrasive environments and provides a significant increase in seal life.

  6. Dancing Volvox: Hydrodynamic Bound States of Swimming Algae

    E-Print Network [OSTI]

    Knut Drescher; Kyriacos C. Leptos; Idan Tuval; Takuji Ishikawa; Timothy J. Pedley; Raymond E. Goldstein

    2009-01-14T23:59:59.000Z

    The spherical alga Volvox swims by means of flagella on thousands of surface somatic cells. This geometry and its large size make it a model organism for studying the fluid dynamics of multicellularity. Remarkably, when two nearby Volvox swim close to a solid surface, they attract one another and can form stable bound states in which they "waltz" or "minuet" around each other. A surface-mediated hydrodynamic attraction combined with lubrication forces between spinning, bottom-heavy Volvox explains the formation, stability and dynamics of the bound states. These phenomena are suggested to underlie observed clustering of Volvox at surfaces.

  7. Semiclassical hydrodynamics of a quantum Kane model for semiconductors

    E-Print Network [OSTI]

    Luigi Barletti; Giovanni Borgioli; Giovanni Frosali

    2014-02-17T23:59:59.000Z

    In this paper we derive a semiclassical hydrodynamic system for electron densities and currents in the two energy bands of a semiconductor. We use the semiclassical Wigner equation with a k.p Hamiltonian and a BGK dissipative term to construct the first two moment equations. The closure of the moment system is obtained using the Maximum Entropy Principle, by minimizing a Gibbs free-energy functional under suitable constraints. We prove that the constraint equations can be uniquely solved, i.e. that the local equilibrium state can be parametrized by the density and velocity field. Some BGK-like models are proposed to mimic the quantum interband migration.

  8. Hydrodynamic Focusing Micropump Module with PDMS/Nickel Particle

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm) HarmonicbetandEnergyCorrectiveHydrodynamic Focusing

  9. Hydrodynamic experiment provides key data for Stockpile Stewardship

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh School footballHydrogen and Fuel Cell HydrogenHydrodynamic experiment

  10. Numerical Simulation of the Hydrodynamical Combustion to Strange Quark Matter

    E-Print Network [OSTI]

    Brian Niebergal; Rachid Ouyed; Prashanth Jaikumar

    2010-08-27T23:59:59.000Z

    We present results from a numerical solution to the burning of neutron matter inside a cold neutron star into stable (u,d,s) quark matter. Our method solves hydrodynamical flow equations in 1D with neutrino emission from weak equilibrating reactions, and strange quark diffusion across the burning front. We also include entropy change due to heat released in forming the stable quark phase. Our numerical results suggest burning front laminar speeds of 0.002-0.04 times the speed of light, much faster than previous estimates derived using only a reactive-diffusive description. Analytic solutions to hydrodynamical jump conditions with a temperature dependent equation of state agree very well with our numerical findings for fluid velocities. The most important effect of neutrino cooling is that the conversion front stalls at lower density (below approximately 2 times saturation density). In a 2-dimensional setting, such rapid speeds and neutrino cooling may allow for a flame wrinkle instability to develop, possibly leading to detonation.

  11. Hydrodynamic model for electron-hole plasma in graphene

    E-Print Network [OSTI]

    D. Svintsov; V. Vyurkov; S. Yurchenko; T. Otsuji; V. Ryzhii

    2012-01-03T23:59:59.000Z

    We propose a hydrodynamic model describing steady-state and dynamic electron and hole transport properties of graphene structures which accounts for the features of the electron and hole spectra. It is intended for electron-hole plasma in graphene characterized by high rate of intercarrier scattering compared to external scattering (on phonons and impurities), i.e., for intrinsic or optically pumped (bipolar plasma), and gated graphene (virtually monopolar plasma). We demonstrate that the effect of strong interaction of electrons and holes on their transport can be treated as a viscous friction between the electron and hole components. We apply the developed model for the calculations of the graphene dc conductivity, in particular, the effect of mutual drag of electrons and holes is described. The spectra and damping of collective excitations in graphene in the bipolar and monopolar limits are found. It is shown that at high gate voltages and, hence, at high electron and low hole densities (or vice-versa), the excitations are associated with the self-consistent electric field and the hydrodynamic pressure (plasma waves). In intrinsic and optically pumped graphene, the waves constitute quasineutral perturbations of the electron and hole densities (electron-hole sound waves) with the velocity being dependent only on the fundamental graphene constants.

  12. Hydrodynamic Simulation of Supernova Remnants Including Efficient Particle Acceleration

    E-Print Network [OSTI]

    Donald C. Ellison; Anne Decourchelle; Jean Ballet

    2003-08-19T23:59:59.000Z

    A number of supernova remnants (SNRs) show nonthermal X-rays assumed to be synchrotron emission from shock accelerated TeV electrons. The existence of these TeV electrons strongly suggests that the shocks in SNRs are sources of galactic cosmic rays (CRs). In addition, there is convincing evidence from broad-band studies of individual SNRs and elsewhere that the particle acceleration process in SNRs can be efficient and nonlinear. If SNR shocks are efficient particle accelerators, the production of CRs impacts the thermal properties of the shock heated, X-ray emitting gas and the SNR evolution. We report on a technique that couples nonlinear diffusive shock acceleration, including the backreaction of the accelerated particles on the structure of the forward and reverse shocks, with a hydrodynamic simulation of SNR evolution. Compared to models which ignore CRs, the most important hydrodynamical effects of placing a significant fraction of shock energy into CRs are larger shock compression ratios and lower temperatures in the shocked gas. We compare our results, which use an approximate description of the acceleration process, with a more complete model where the full CR transport equations are solved (i.e., Berezhko et al., 2002), and find excellent agreement for the CR spectrum summed over the SNR lifetime and the evolving shock compression ratio. The importance of the coupling between particle acceleration and SNR dynamics for the interpretation of broad-band continuum and thermal X-ray observations is discussed.

  13. Hydrodynamic and hydromagnetic energy spectra from large eddy simulations

    E-Print Network [OSTI]

    N. E. L. Haugen; A. Brandenburg

    2006-06-29T23:59:59.000Z

    Direct and large eddy simulations of hydrodynamic and hydromagnetic turbulence have been performed in an attempt to isolate artifacts from real and possibly asymptotic features in the energy spectra. It is shown that in a hydrodynamic turbulence simulation with a Smagorinsky subgrid scale model using 512^3 meshpoints two important features of the 4096^3 simulation on the Earth simulator (Kaneda et al. 2003, Phys. Fluids 15, L21) are reproduced: a k^{-0.1} correction to the inertial range with a k^{-5/3} Kolmogorov slope and the form of the bottleneck just before the dissipative subrange. Furthermore, it is shown that, while a Smagorinsky-type model for the induction equation causes an artificial and unacceptable reduction in the dynamo efficiency, hyper-resistivity yields good agreement with direct simulations. In the large-scale part of the inertial range, an excess of the spectral magnetic energy over the spectral kinetic energy is confirmed. However, a trend towards spectral equipartition at smaller scales in the inertial range can be identified. With magnetic fields, no explicit bottleneck effect is seen.

  14. The dynamics of polymers in solution with hydrodynamic memory

    E-Print Network [OSTI]

    V. Lisy; J. Tothova; B. Brutovsky; A. V Zatovsky

    2005-09-15T23:59:59.000Z

    The theory of the dynamics of polymers in solution is developed coming from the hydrodynamic theory of the Brownian motion (BM) and the Rouse-Zimm (RZ) model. It is shown that the time correlation functions describing the polymer motion essentially differ from those in the previous RZ models based on the Einstein theory of BM. The MSD of the polymer coil is at short times proportional to t^2 (instead of t). At long times it contains additional (to the Einstein term) contributions, the leading of which is ~ t^{1/2}. The relaxation of the internal normal modes of the polymer differs from the traditional exponential decay. This is displayed in the tails of their correlation functions, the longest-lived being ~ t^{-3/2} in the Rouse limit and t^{-5/2} in the Zimm case when the hydrodynamic interaction is strong. It is discussed that the found peculiarities, in particular a slower diffusion of the coil, should be observable in dynamic scattering experiments. The dynamic structure factor and the first cumulant of the polymer coil are calculated. The theory is extended to the situation when the dynamics of the studied polymer is influenced by the presence of other polymers in dilute solution.

  15. Dynamic mesoscale model of dipolar fluids via fluctuating hydrodynamics

    SciTech Connect (OSTI)

    Persson, Rasmus A. X.; Chu, Jhih-Wei, E-mail: jwchu@nctu.edu.tw [Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu 30068, Taiwan (China); Department of Biological Science and Technology, National Chiao Tung University, Hsinchu 30068, Taiwan (China); Voulgarakis, Nikolaos K. [Department of Mathematics, Washington State University, Richland, Washington 99372 (United States)

    2014-11-07T23:59:59.000Z

    Fluctuating hydrodynamics (FHD) is a general framework of mesoscopic modeling and simulation based on conservational laws and constitutive equations of linear and nonlinear responses. However, explicit representation of electrical forces in FHD has yet to appear. In this work, we devised an Ansatz for the dynamics of dipole moment densities that is linked with the Poisson equation of the electrical potential ? in coupling to the other equations of FHD. The resulting ?-FHD equations then serve as a platform for integrating the essential forces, including electrostatics in addition to hydrodynamics, pressure-volume equation of state, surface tension, and solvent-particle interactions that govern the emergent behaviors of molecular systems at an intermediate scale. This unique merit of ?-FHD is illustrated by showing that the water dielectric function and ion hydration free energies in homogeneous and heterogenous systems can be captured accurately via the mesoscopic simulation. Furthermore, we show that the field variables of ?-FHD can be mapped from the trajectory of an all-atom molecular dynamics simulation such that model development and parametrization can be based on the information obtained at a finer-grained scale. With the aforementioned multiscale capabilities and a spatial resolution as high as 5 Å, the ?-FHD equations represent a useful semi-explicit solvent model for the modeling and simulation of complex systems, such as biomolecular machines and nanofluidics.

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

    E-Print Network [OSTI]

    Krishna Rajagopal; Nilesh Tripuraneni

    2010-02-16T23:59:59.000Z

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

  17. RIS-M-2579 CAN NEUTRON BEAM COMPONENTS AND RADIOGRAPHIC IMAGE QUALITY BE

    E-Print Network [OSTI]

    under the NRWG Test Program are summa- rized and compared. INIS Descriptors; CALIBRATION; DENSITY; FUEL

  18. Physiologic and Radiographic Evidence of the Distal Edge of the Proton Beam in Craniospinal Irradiation

    SciTech Connect (OSTI)

    Krejcarek, Stephanie C. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Grant, P. Ellen [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Henson, John W. [Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Pappas Center for Neuro-oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Tarbell, Nancy J. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Yock, Torunn I. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)]. E-mail: tyock@partners.org

    2007-07-01T23:59:59.000Z

    Purpose: Fatty replacement of bone marrow resulting from radiation therapy can be seen on T1-weighted magnetic resonance (MR) images. We evaluated the radiographic appearance of the vertebral bodies in children treated with proton craniospinal irradiation (CSI) to illustrate the distal edge effect of proton radiotherapy. Methods and Materials: The study cohort consisted of 13 adolescents aged 12-18 years who received CSI with proton radiotherapy at Massachusetts General Hospital. Ten of these patients had reached maximal or near-maximal growth. Proton beam radiation for these 10 patients was delivered to the thecal sac and exiting nerve roots only, whereas the remaining 3 patients had a target volume that included the thecal sac, exiting nerve roots, and entire vertebral bodies. Median CSI dose was 27 [range, 23.4-36] cobalt gray equivalent (CGE) given in 1.8-CGE fractions. Magnetic resonance images of the spine were obtained after completion of radiotherapy. Results: Magnetic resonance images of patients who received proton radiotherapy to the thecal sac only demonstrate a sharp demarcation of hyperintense T1-weighted signal in the posterior aspects of the vertebral bodies, consistent with radiation-associated fatty marrow replacement. Magnetic resonance images of the patients prescribed proton radiotherapy to the entire vertebral column had corresponding hyperintense T1-weighted signal involving the entire vertebral bodies. Conclusion: The sharp delineation of radiation-associated fatty marrow replacement in the vertebral bodies demonstrates the rapid decrease in energy at the edge of the proton beam. This provides evidence for a sharp fall-off in radiation dose and supports the premise that proton radiotherapy spares normal tissues unnecessary irradiation.

  19. THERMO-HYDRODYNAMICS OF DEVELOPING FLOW IN A RECTANGULAR MINI-CHANNEL ARRAY Gaurav Agarwal

    E-Print Network [OSTI]

    Khandekar, Sameer

    THERMO-HYDRODYNAMICS OF DEVELOPING FLOW IN A RECTANGULAR MINI-CHANNEL ARRAY Gaurav Agarwal Dept of Technology Kanpur Kanpur (UP) 208016, India samkhan@iitk.ac.in ABSTRACT Thermo-hydrodynamic performance on developing flows. Thus, the study reveals that conventional theory, which predicts thermo

  20. Coupling upland watershed and downstream waterbody hydrodynamic and water quality models

    E-Print Network [OSTI]

    . Such models lack the capacity to simulate the hydrodynamics and water quality processes of larger waterCoupling upland watershed and downstream waterbody hydrodynamic and water quality models (SWAT and CE-QUAL-W2) for better water resources management in complex river basins B. Debele & R. Srinivasan

  1. An Investigation on the Hydrodynamics and Sediment Dynamics on an Intertidal Mudflat in

    E-Print Network [OSTI]

    Talke, Stefan

    An Investigation on the Hydrodynamics and Sediment Dynamics on an Intertidal Mudflat in Central San on the Hydrodynamics and Sediment Dynamics on an Intertidal Mudflat in Central San Francisco Bay Copyright 2005 on an Intertidal Mudflat in Central San Francisco Bay by Stefan Andreas Talke Doctor of Philosophy in Engineering

  2. Role of Brownian motion hydrodynamics on nanofluid thermal conductivity William Evans

    E-Print Network [OSTI]

    Fish, Jacob

    Role of Brownian motion hydrodynamics on nanofluid thermal conductivity William Evans Lockheed of solid nanoparticles nanofluids to demonstrate that the hydrodynamics effects associated with Brownian motion have only a minor effect on the thermal conductivity of the nanofluid. This analysis is supported

  3. Experimental study of the hydrodynamics and cluster formation in a Circulating Fluidized Bed. Annual report, 1990

    SciTech Connect (OSTI)

    Gautam, M.; Johnson, E.

    1991-01-01T23:59:59.000Z

    A novel non-invasive gas-solid flow measuring technique being developed and tested for studying the hydrodynamics inside the riser of a Circulating Fluidized Bed (CFB). First of the two aims of the overall program, namely, design, development and testing of the technique to characterize the particle and gas velocities in two-phase flows was accomplished in the past year. The ``fringe-model`` laser Doppler anemometry concept has been modified and extended by using particles coated with a fluorescent dye and introducing a narrow band pass filter in the receiving optics. The technique permits optical discrimination between the scattered light (laser wavelength from undyed particles) and the fluorescence emission (longer wavelength). Results from extensive testing of various dye-solvent combinations, counter processor settings, signal-to noise optimization and subsequent flow measurements in the test section have shown that the technique can effectively discriminate between two classes of particles--the smaller seed particles for the gas phase data and the larger bed particles. Use of a two-watt Argon-Ion laser assisted in the non-intrusive probing of the gas-solid flow and in enhancing the signal-to-noise ratio. An uncertainty analysis of LDA measurements is presented. Design of the cold flow CFB model, presently under fabrication, is outlined in this report. The Plexiglas CFB model will be employed for the riser core-annular flow studies using the fluorescence-emission based laser-Doppler anemometry. The results from this study will present a unique detailed description of the complex gas-solid behavior in the CFB riser.

  4. Experimental study of the hydrodynamics and cluster formation in a Circulating Fluidized Bed

    SciTech Connect (OSTI)

    Gautam, M.; Johnson, E.

    1991-01-01T23:59:59.000Z

    A novel non-invasive gas-solid flow measuring technique being developed and tested for studying the hydrodynamics inside the riser of a Circulating Fluidized Bed (CFB). First of the two aims of the overall program, namely, design, development and testing of the technique to characterize the particle and gas velocities in two-phase flows was accomplished in the past year. The fringe-model'' laser Doppler anemometry concept has been modified and extended by using particles coated with a fluorescent dye and introducing a narrow band pass filter in the receiving optics. The technique permits optical discrimination between the scattered light (laser wavelength from undyed particles) and the fluorescence emission (longer wavelength). Results from extensive testing of various dye-solvent combinations, counter processor settings, signal-to noise optimization and subsequent flow measurements in the test section have shown that the technique can effectively discriminate between two classes of particles--the smaller seed particles for the gas phase data and the larger bed particles. Use of a two-watt Argon-Ion laser assisted in the non-intrusive probing of the gas-solid flow and in enhancing the signal-to-noise ratio. An uncertainty analysis of LDA measurements is presented. Design of the cold flow CFB model, presently under fabrication, is outlined in this report. The Plexiglas CFB model will be employed for the riser core-annular flow studies using the fluorescence-emission based laser-Doppler anemometry. The results from this study will present a unique detailed description of the complex gas-solid behavior in the CFB riser.

  5. Hydro-dynamical models for the chaotic dripping faucet

    E-Print Network [OSTI]

    P. Coullet; L. Mahadevan; C. S. Riera

    2004-08-20T23:59:59.000Z

    We give a hydrodynamical explanation for the chaotic behaviour of a dripping faucet using the results of the stability analysis of a static pendant drop and a proper orthogonal decomposition (POD) of the complete dynamics. We find that the only relevant modes are the two classical normal forms associated with a Saddle-Node-Andronov bifurcation and a Shilnikov homoclinic bifurcation. This allows us to construct a hierarchy of reduced order models including maps and ordinary differential equations which are able to qualitatively explain prior experiments and numerical simulations of the governing partial differential equations and provide an explanation for the complexity in dripping. We also provide a new mechanical analogue for the dripping faucet and a simple rationale for the transition from dripping to jetting modes in the flow from a faucet.

  6. A Co-moving Coordinate System for Relativistic Hydrodynamics

    E-Print Network [OSTI]

    Scott Pratt

    2006-12-03T23:59:59.000Z

    The equations of relativistic hydrodynamics are transformed so that steps forward in time preserves local simultaneity. In these variables, the space-time coordinates of neighboring points on the mesh are simultaneous according to co-moving observers. Aside from the time step varying as a function of the location on the mesh, the local velocity gradient and the local density then evolve according to non-relativistic equations of motion. Analytic solutions are found for two one-dimensional cases with constant speed of sound. One solution has a Gaussian density profile when mapped into the new coordinates. That solution is analyzed for the effects of longitudinal acceleration in relativistic heavy ion collisions at RHIC, especially in regards to two-particle correlation measurements of the longitudinal size.

  7. Black brane entropy and hydrodynamics: The boost-invariant case

    SciTech Connect (OSTI)

    Booth, Ivan; Heller, Michal P.; Spalinski, Michal [Department of Mathematics and Statistics, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, A1C 5S7 (Canada); Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Cracow (Poland); Soltan Institute for Nuclear Studies, 00-681 Warsaw (Poland) and Physics Department, University of Bialystok, 15-424 Bialystok (Poland)

    2009-12-15T23:59:59.000Z

    The framework of slowly evolving horizons is generalized to the case of black branes in asymptotically anti-de Sitter spaces in arbitrary dimensions. The results are used to analyze the behavior of both event and apparent horizons in the gravity dual to boost-invariant flow. These considerations are motivated by the fact that at second order in the gradient expansion the hydrodynamic entropy current in the dual Yang-Mills theory appears to contain an ambiguity. This ambiguity, in the case of boost-invariant flow, is linked with a similar freedom on the gravity side. This leads to a phenomenological definition of the entropy of black branes. Some insights on fluid/gravity duality and the definition of entropy in a time-dependent setting are elucidated.

  8. Absolute Lineshifts - A new diagnostic for stellar hydrodynamics

    E-Print Network [OSTI]

    Dainis Dravins

    2003-02-28T23:59:59.000Z

    For hydrodynamic model atmospheres, absolute lineshifts are becoming an observable diagnostic tool beyond the classical ones of line-strength, -width, -shape, and -asymmetry. This is the wavelength displacement of different types of spectral lines away from the positions naively expected from the Doppler shift caused by stellar radial motion. Caused mainly by correlated velocity and brightness patterns in granular convection, such absolute lineshifts could in the past be studied only for the Sun (since the relative Sun-Earth motion, and the ensuing Doppler shift is known). For other stars, this is now becoming possible thanks to three separate developments: (a) Astrometric determination of stellar radial motion; (b) High-resolution spectrometers with accurate wavelength calibration, and (c) Accurate laboratory wavelengths for several atomic species. Absolute lineshifts offer a tool to segregate various 2- and 3-dimensional models, and to identify non-LTE effects in line formation.

  9. Absolute Lineshifts - A new diagnostic for stellar hydrodynamics

    E-Print Network [OSTI]

    Dravins, D

    2003-01-01T23:59:59.000Z

    For hydrodynamic model atmospheres, absolute lineshifts are becoming an observable diagnostic tool beyond the classical ones of line-strength, -width, -shape, and -asymmetry. This is the wavelength displacement of different types of spectral lines away from the positions naively expected from the Doppler shift caused by stellar radial motion. Caused mainly by correlated velocity and brightness patterns in granular convection, such absolute lineshifts could in the past be studied only for the Sun (since the relative Sun-Earth motion, and the ensuing Doppler shift is known). For other stars, this is now becoming possible thanks to three separate developments: (a) Astrometric determination of stellar radial motion; (b) High-resolution spectrometers with accurate wavelength calibration, and (c) Accurate laboratory wavelengths for several atomic species. Absolute lineshifts offer a tool to segregate various 2- and 3-dimensional models, and to identify non-LTE effects in line formation.

  10. Hydrodynamic transport coefficients in relativistic scalar field theory

    SciTech Connect (OSTI)

    Jeon, S. [Department of Physics FM-15, University of Washington, Seattle, Washington 98195 (United States)] [Department of Physics FM-15, University of Washington, Seattle, Washington 98195 (United States)

    1995-09-15T23:59:59.000Z

    Hydrodynamic transport coefficients may be evaluated from first principals in a weakly coupled scalar field theory at an arbitrary temperature. In a theory with cubic and quartic interactions, the infinite class of diagrams which contributes to the leading weak coupling behavior is identified and summed. The resulting expression may be reduced to a single linear integral equation, which is shown to be identical to the corresponding result obtained from a linearized Boltzmann equation describing effective thermal excitations with temperature-dependent masses and scattering amplitudes. The effective Boltzmann equation is valid even at very high temperature where the thermal lifetime and mean free path are short compared to the Compton wavelength of the fundamental particles. Numerical results for the shear and the bulk viscosities are presented.

  11. Follow-up on the Los Alamos National Laboratory Hydrodynamic Test Program

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directed offOCHCO2: FinalOffers3.pdf0-45.pdf Flash2010-45.pdfFlash2011-43andProperty ControlFollow-up on the

  12. Impact of hydrodynamics on coal liquefaction. Final technical report

    SciTech Connect (OSTI)

    Kang, D.; Ying, D.H.S.; Givens, E.N.

    1983-09-01T23:59:59.000Z

    We have attempted to determine the hydrodynamic effects of various reactor configurations on coal liquefaction, to help select the optimal reactor configuration and to provide additional understanding of coal liquefaction reaction kinetics, which cannot be definitively determined by a CSTR alone. Only a qualitative understanding of the fluid dynamic effects on product yields has been perceived by operating various sizes of open-column tubular reactors, because the fluid-dynamic characteristics of these reactors were not clearly understood and could not be varied significantly. Indirect studies, by cold-flow simulation, have been of little help in defining the fluid dynamic impact on coal liquefaction. Comparison of actual coal liquefaction data from both the plug-flow reactor and the CSTR showed that the plug-flow configuration had various advantages. Reactor yields improved significantly, especially the primary product conversions. At 840/sup 0/F and residence times of 29 and 40 min, coal and preasphaltene conversions were enhanced approximately 6 and 10%, respectively. At these conditions, the plug-flow reactor also yielded about 10% more oils than the CSTR with significant increase in hydrogen utilization. Also, this study provided an opportunity to examine the soundness of APCI/ICRC's sequential kinetic model, by interfacing the plug-flow and CSTR yield data. Transforming CSTR yields to plug-flow data showed that product yields deviated considerably from the measured plug-flow data, suggesting the need to improve the existing reaction model. Having both CSTR and plug-flow reactor data bases is important for developing a sound coal reaction model and for determining hydrodynamic effects on coal liquefaction in a direct way. The results will lead to an optimized reactor configuration as well as optimized operation. 5 references, 23 figures, 20 tables.

  13. P-23 Highlights 6/10/12: Cygnus Dual Beam Radiographic Facility Refurbishment completed at U1A tunnel in Nevada NNSS meeting Level 2 milestone

    SciTech Connect (OSTI)

    Deyoung, Anemarie [Los Alamos National Laboratory; Smith, John R. [Los Alamos National Laboratory

    2012-05-03T23:59:59.000Z

    A moratorium was placed on U.S. underground nuclear testing in 1992. In response, the Stockpile Stewardship Program was created to maintain readiness of the existing nuclear inventory through several efforts such as computer modeling, material analysis, and subcritical nuclear experiments (SCEs). As in the underground test era, the Nevada National Security Site (NNSS), formerly the Nevada Test Site, provides a safe and secure environment for SCEs by the nature of its isolated and secure facilities. A major tool for SCE diagnosis installed in the 05 drift laboratory is a high energy x-ray source used for time resolved imaging. This tool consists of two identical sources (Cygnus 1 and Cygnus 2) and is called the Cygnus Dual Beam Radiographic Facility (Figs. 2-6). Each Cygnus machine has 5 major elements: Marx Generator, Pulse Forming Line (PFL), Coaxial Transmission Line (CTL), 3-cell Inductive Voltage Adder (IVA), and Rod Pinch Diode. Each machine is independently triggered and may be fired in separate tests (staggered mode), or in a single test where there is submicrosecond separation between the pulses (dual mode). Cygnus must operate as a single shot machine since on each pulse the diode electrodes are destroyed. The diode is vented to atmosphere, cleaned, and new electrodes are inserted for each shot. There is normally two shots per day on each machine. Since its installation in 2003, Cygnus has participated in: 4 Subcritical Experiments (Armando, Bacchus, Barolo A, and Barolo B), a 12 shot plutonium physics series (Thermos), and 2 plutonium step wedge calibration series (2005, 2011), resulting in well over 1000 shots. Currently the Facility is in preparation for 2 SCEs scheduled for this calendar year - Castor and Pollux. Cygnus has performed well during 8 years of operations at NNSS. Many improvements in operations and performance have been implemented during this time. Throughout its service at U1a, major maintenance and replacement of many hardware items were delayed due to programmatic requirements. It is anticipated that Cygnus will be in service at U1a for another 5 years. With this assumption, it was realized that significant resources and effort should be allotted to bring the hardware back to its original condition, or even to improve elements when appropriate. The Cygnus Refurbishment and Enhancement Project started in April, 2011 with the intent to encompass a major overhaul of Cygnus.

  14. Non-Relativistic Parity-Violating Hydrodynamics in Two Spatial Dimensions

    E-Print Network [OSTI]

    Matthias Kaminski; Sergej Moroz

    2014-04-01T23:59:59.000Z

    We construct the non-relativistic parity-violating hydrodynamic description of a two-dimensional dissipative, normal fluid in presence of small U(1) background fields and vorticity. This is achieved by taking the non-relativistic limit of the recently developed relativistic hydrodynamics in 2+1 dimensions. We identify and interpret the resulting parity-violating contributions to the non-relativistic constitutive relations, which include the Hall current flowing perpendicular to the temperature gradient, the Hall viscosity and the Leduc-Righi energy current. Also a comparison of our findings is made with the non-relativistic parity-violating hydrodynamics obtained from a light-cone dimensional reduction.

  15. Effect of Second-Order Hydrodynamics on a Floating Offshore Wind Turbine

    SciTech Connect (OSTI)

    Roald, L.; Jonkman, J.; Robertson, A.

    2014-05-01T23:59:59.000Z

    The design of offshore floating wind turbines uses design codes that can simulate the entire coupled system behavior. At the present, most codes include only first-order hydrodynamics, which induce forces and motions varying with the same frequency as the incident waves. Effects due to second- and higher-order hydrodynamics are often ignored in the offshore industry, because the forces induced typically are smaller than the first-order forces. In this report, first- and second-order hydrodynamic analysis used in the offshore oil and gas industry is applied to two different wind turbine concepts--a spar and a tension leg platform.

  16. HEAVY DUST OBSCURATION OF z = 7 GALAXIES IN A COSMOLOGICAL HYDRODYNAMIC SIMULATION

    SciTech Connect (OSTI)

    Kimm, Taysun; Cen, Renyue [Department of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08544 (United States)

    2013-10-10T23:59:59.000Z

    Hubble Space Telescope observations with the Wide Field Camera 3/Infrared reveal that galaxies at z ? 7 have very blue ultraviolet (UV) colors, consistent with these systems being dominated by young stellar populations with moderate or little attenuation by dust. We investigate UV and optical properties of the high-z galaxies in the standard cold dark matter model using a high-resolution adaptive mesh refinement cosmological hydrodynamic simulation. For this purpose, we perform panchromatic three-dimensional dust radiative transfer calculations on 198 galaxies of stellar mass 5 × 10{sup 8}-3 × 10{sup 10} M{sub ?} with three parameters: the dust-to-metal ratio, the extinction curve, and the fraction of directly escaped light from stars (f{sub esc}). Our stellar mass function is found to be in broad agreement with Gonzalez et al., independent of these parameters. We find that our heavily dust-attenuated galaxies (A{sub V} ? 1.8) can also reasonably match modest UV-optical colors, blue UV slopes, as well as UV luminosity functions, provided that a significant fraction (?10%) of light directly escapes from them. The observed UV slope and scatter are better explained with a Small-Magellanic-Cloud-type extinction curve, whereas a Milky-Way-type curve also predicts blue UV colors due to the 2175 Å bump. We expect that upcoming observations by the Atacama Large Millimeter/submillimeter Array will be able to test this heavily obscured model.

  17. A Module for Radiation Hydrodynamic Calculations With ZEUS-2D Using Flux-Limited Diffusion

    E-Print Network [OSTI]

    N. J. Turner; J. M. Stone

    2001-02-08T23:59:59.000Z

    A module for the ZEUS-2D code is described which may be used to solve the equations of radiation hydrodynamics to order unity in v/c, in the flux-limited diffusion (FLD) approximation. In this approximation, the tensor Eddington factor f which closes the radiation moment equations is chosen to be an empirical function of radiation energy density. This is easier to implement and faster than full-transport techniques, in which f is computed by solving the transfer equation. However, FLD is less accurate when the flux has a component perpendicular to the gradient in radiation energy density, and in optically thin regions when the radiation field depends strongly on angle. The material component of the fluid is here assumed to be in local thermodynamic equilibrium. The energy equations are operator-split, with transport terms, radiation diffusion term, and other source terms evolved separately. Transport terms are applied using the same consistent transport algorithm as in ZEUS-2D. The radiation diffusion term is updated using an alternating-direction implicit method with convergence checking. Remaining source terms are advanced together implicitly using numerical root-finding. However when absorption opacity is zero, accuracy is improved by treating compression and expansion source terms using time-centered differencing. Results are discussed for test problems including radiation-damped linear waves, radiation fronts propagating in optically-thin media, subcritical and supercritical radiating shocks, and an optically-thick shock in which radiation dominates downstream pressure.

  18. Relativistic Hydrodynamic Flows Using Spatial and Temporal Adaptive Structured Mesh Refinement

    E-Print Network [OSTI]

    Peng Wang; Tom Abel; Weiqun Zhang

    2007-12-31T23:59:59.000Z

    Astrophysical relativistic flow problems require high resolution three-dimensional numerical simulations. In this paper, we describe a new parallel three-dimensional code for simulations of special relativistic hydrodynamics (SRHD) using both spatially and temporally structured adaptive mesh refinement (AMR). We used the method of lines to discretize the SRHD equations spatially and a total variation diminishing (TVD) Runge-Kutta scheme for time integration. For spatial reconstruction, we have implemented piecewise linear method (PLM), piecewise parabolic method (PPM), third order convex essentially non-oscillatory (CENO) and third and fifth order weighted essentially non-oscillatory (WENO) schemes. Flux is computed using either direct flux reconstruction or approximate Riemann solvers including HLL, modified Marquina flux, local Lax-Friedrichs flux formulas and HLLC. The AMR part of the code is built on top of the cosmological Eulerian AMR code {\\sl enzo}. We discuss the coupling of the AMR framework with the relativistic solvers. Via various test problems, we emphasize the importance of resolution studies in relativistic flow simulations because extremely high resolution is required especially when shear flows are present in the problem. We also present the results of two 3d simulations of astrophysical jets: AGN jets and GRB jets. Resolution study of those two cases further highlights the need of high resolutions to calculate accurately relativistic flow problems.

  19. Hydrodynamical simulations of the decay of high-speed molecular turbulence. II. Divergence from isothermality

    E-Print Network [OSTI]

    G. Pavlovski; M. D. Smith; M. -M. Mac Low

    2006-02-17T23:59:59.000Z

    A roughly constant temperature over a wide range of densities is maintained in molecular clouds through radiative heating and cooling. An isothermal equation of state is therefore frequently employed in molecular cloud simulations. However, the dynamical processes in molecular clouds include shock waves, expansion waves, cooling induced collapse and baroclinic vorticity, all incompatible with the assumption of a purely isothermal flow. Here, we incorporate an energy equation including all the important heating and cooling rates and a simple chemical network into simulations of three-dimensional, hydrodynamic, decaying turbulence. This allows us to test the accuracy of the isothermal assumption by directly comparing a model run with the modified energy equation to an isothermal model. We compute an extreme case in which the initial turbulence is sufficiently strong to dissociate much of the gas and alter the specific heat ratio. The molecules then reform as the turbulence weakens. We track the true specific heat ratio as well as its effective value. We analyse power spectra, vorticity and shock structures, and discuss scaling laws for decaying turbulence. We derive some limitations to the isothermal approximation for simulations of the interstellar medium using simple projection techniques. Overall, even given the extreme conditions, we find that an isothermal flow provides an adequate physical and observational description of many properties. The main exceptions revealed here concern behaviour directly related to the high temperature zones behind the shock waves.

  20. SU-E-I-48: The Behavior of AEC in Scan Regions Outside the Localizer Radiograph FOV: An In Phantom Study of CT Systems From Four Vendors

    SciTech Connect (OSTI)

    Supanich, M [Rush University Medical Center, Chicago, IL (United States); Bevins, N [Henry Ford Health System, Detroit, MI (United States)

    2014-06-01T23:59:59.000Z

    Purpose: This review of scanners from 4 major manufacturers examines the clinical impact of performing CT scans that extend into areas of the body that were not acquired in the CT localizer radiograph. Methods: Anthropomorphic chest and abdomen phantoms were positioned together on the tables of CT scanners from 4 different vendors. All of the scanners offered an Automatic Exposure Control (AEC) option with both lateral and axial tube current modulation. A localizer radiograph was taken covering the entire extent of both phantoms and then the scanner's Chest-Abdomen-Pelvis (CAP) study was performed with the clinical AEC settings employed and the scan and reconstruction range extending from the superior portion of the chest phantom through the inferior portion of the abdomen phantom. A new study was then initiated with a localizer radiograph extending the length of the chest phantom (not covering the abdomen phantom). The same CAP protocol and AEC settings were then used to scan and reconstruct the entire length of both phantoms. Scan parameters at specific locations in the abdomen phantom from both studies were investigated using the information contained in the DICOM metadata of the reconstructed images. Results: The AEC systems on all scanners utilized different tube current settings in the abdomen phantom for the scan completed without the full localizer radiograph. The AEC system behavior was also scanner dependent with the default manual tube current, the maximum tube current and the tube current at the last known position observed as outcomes. Conclusion: The behavior of the AEC systems of CT scanners in regions not covered by the localizer radiograph is vendor dependent. To ensure optimal image quality and radiation exposure it is important to include the entire planned scan region in the localizer radiograph.

  1. Challenges in Simulation of Aerodynamics, Hydrodynamics, and Mooring-Line Dynamics of Floating Offshore Wind Turbines

    SciTech Connect (OSTI)

    Matha, D.; Schlipf, M.; Cordle, A.; Pereira, R.; Jonkman, J.

    2011-10-01T23:59:59.000Z

    This paper presents the current major modeling challenges for floating offshore wind turbine design tools and describes aerodynamic and hydrodynamic effects due to rotor and platform motions and usage of non-slender support structures.

  2. Design of the All-Electric Ship: Focus on Integrated Power System Coupled to Hydrodynamics

    E-Print Network [OSTI]

    Prempraneerach, P.

    2008-01-01T23:59:59.000Z

    We present a detailed model of the integrated power system coupled to hydrodynamics that allows us to study global sensitivities in the All-Electric Ship. A novel element of our formulation is the stochastic modeling of ...

  3. A model for analyzing the effects of hydrodynamic forces on cell adhesion in a perfused bioreactor

    E-Print Network [OSTI]

    Owens, Bryan D

    2007-01-01T23:59:59.000Z

    In bioreactor culture systems that aim to provide a convective flux to address mass transport limitations of oxygen and other nutrients, large hydrodynamic forces and shear stress can potentially serve as a negative signals ...

  4. Simulation and Optimization of DPP Hydrodynamics and Radiation Transport for EUV Lithography Devices

    E-Print Network [OSTI]

    Harilal, S. S.

    be used to study the hydrodynamics and radiation in two-gas mixtures of dense plasma focus (DPF) and z the HEIGHTS- EUV package are schematically shown in Figure 1: a) A dense plasma focus device, b) A hollow

  5. Scattering and nonlinear bound states of hydrodynamically coupled particles in a narrow channel

    E-Print Network [OSTI]

    Doyle, Patrick S.

    We model a pair of hydrodynamically interacting particles confined in a channel with thin rectangular cross section. We find that the particles have a finite region of attraction, which arises from the screening of dipolar ...

  6. Volumetric analysis of fish swimming hydrodynamics using synthetic aperture particle image velocimetry

    E-Print Network [OSTI]

    Mendelson, Leah Rose

    2013-01-01T23:59:59.000Z

    Abstract This thesis details the implementation of a three-dimensional PIV system to study the hydrodynamics of freely swimming Giant Danio (Danio aequipinnatus). Volumetric particle fields are reconstructed using synthetic ...

  7. Measurements and Linear Wave Theory Based Simulations of Vegetated Wave Hydrodynamics for Practical Applications

    E-Print Network [OSTI]

    Anderson, Mary Elizabeth

    2011-10-21T23:59:59.000Z

    nor implemented in current hydrodynamic models. A series of laboratory experiments were conducted at the Haynes Coastal Engineering Laboratory and in a two-dimensional flume at Texas A and M University to investigate the influence of relative...

  8. The role of hydrodynamic interactions in the dynamics and viscoelasticity of actin networks

    E-Print Network [OSTI]

    Karimi, Reza, Ph. D. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    Actin, the primary component of the cytoskeleton, is the most studied semi-flexible filament, yet its dynamics remains elusive. We show that hydrodynamic interactions (HIs) significantly alter the time scale of actin ...

  9. CFD study of hydrodynamic signal perception by fish using the lateral line system

    E-Print Network [OSTI]

    Rapo, Mark Andrew

    2009-01-01T23:59:59.000Z

    The lateral line system on fish has been found to aid in schooling behavior, courtship communication, active and passive hydrodynamic imaging, and prey detection. The most widely used artificial prey stimulus has been the ...

  10. A Smoothed Particle Hydrodynamics-Based Fluid Model With a Spatially...

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

    A Smoothed Particle Hydrodynamics-Based Fluid Model With a Spatially Dependent Viscosity Authors: Martys, N.S., George, W.L., Chun, B., Lootens, D. A smoothed particle...

  11. Experimental hydrodynamics of spherical projectiles impacting on a free surface using high speed imaging techniques

    E-Print Network [OSTI]

    Laverty, Stephen Michael

    2005-01-01T23:59:59.000Z

    This thesis looks at the hydrodynamics of spherical projectiles impacting the free surface using a unique experimental WebLab facility. Experiments were performed to determine the force impact coefficients of spheres and ...

  12. A Model for the Dynamic User-Equilibrium Problem Using a Hydrodynamic Theory Approach

    E-Print Network [OSTI]

    Perakis, Georgia

    In this paper we study the dynamic user-equilibrium problem. The development of Intelligent Vehicle Highway Systems (IVHS) has made this problem very popular in the recent years. In this paper we take a hydrodynamic theory ...

  13. The hydrodynamic stability of crossflow vortices in the Bdewadt boundary layer

    E-Print Network [OSTI]

    The hydrodynamic stability of crossflow vortices in the Bödewadt boundary layer N. A. Culverhouse the critical Reynolds number. extends the laminar flow region. decreasing the magnitude of the crossflow

  14. Hydrodynamics and heat transfer during flow boiling instabilities in a single microchannel

    E-Print Network [OSTI]

    Aussillous, Pascale

    Hydrodynamics and heat transfer during flow boiling instabilities in a single microchannel July 2008 Keywords: Boiling Microchannels Visualisation Flow boiling instabilities Heat transfer a b intensification heat removal. Flow boiling heat transfer in microchannel geometry and the associated flow

  15. Energy Conversion Efficiency of Nanofluidic Batteries: Hydrodynamic Slip and Access Resistance

    E-Print Network [OSTI]

    Chang, Hsueh-Chia

    Energy Conversion Efficiency of Nanofluidic Batteries: Hydrodynamic Slip and Access Resistance Yu channels. INTRODUCTION Nanofluidic batteries are interesting energy generation systems for converting with this nanofluidic battery system has gained considerable attention. One of the challenges for the nanofluidic

  16. Physico-chemical hydrodynamics of droplets on textured surfaces with engineered micro/nanostructures

    E-Print Network [OSTI]

    Park, Kyoo Chul

    2013-01-01T23:59:59.000Z

    Understanding physico-chemical hydrodynamics of droplets on textured surfaces is of fundamental and practical significance for designing a diverse range of engineered surfaces such as low-reflective, self-cleaning or ...

  17. On the hydrodynamics of the matter reinserted within superstellar clusters

    E-Print Network [OSTI]

    Tenorio-Tagle, G; Palous, S S J; Tenorio-Tagle, Guillermo; Wunsch, Richard; Palous, Sergiy Silich & Jan

    2006-01-01T23:59:59.000Z

    We present semi-analytical and numerical models, accounting for the impact of radiative cooling on the hydrodynamics of the matter reinserted as strong stellar winds and supernovae within the volume occupied by young, massive and compact superstellar clusters. First of all we corroborate the location of the threshold line in the mechanical energy input rate vs the cluster size plane, found by Silich et al. (2004). Such a line separates clusters able to drive a quasi-adiabatic or a strongly radiative wind from clusters in which catastrophic cooling occurs within the star cluster volume. Then we show that the latter, clusters above the threshold line, undergo a bimodal behavior in which the central densest zones cool rapidly and accumulate the injected matter to eventually feed further generations of star formation, while the outer zones are still able to drive a stationary wind. The results are presented into a series of universal dimensionless diagrams from which one can infer: the size of the two zones, the ...

  18. Low Mach Number Fluctuating Hydrodynamics of Diffusively Mixing Fluids

    E-Print Network [OSTI]

    A. Donev; A. J. Nonaka; Y. Sun; T. G. Fai; A. L. Garcia; J. B. Bell

    2014-04-29T23:59:59.000Z

    We formulate low Mach number fluctuating hydrodynamic equations appropriate for modeling diffusive mixing in isothermal mixtures of fluids with different density and transport coefficients. These equations eliminate the fluctuations in pressure associated with the propagation of sound waves by replacing the equation of state with a local thermodynamic constraint. We demonstrate that the low Mach number model preserves the spatio-temporal spectrum of the slower diffusive fluctuations. We develop a strictly conservative finite-volume spatial discretization of the low Mach number fluctuating equations in both two and three dimensions and construct several explicit Runge-Kutta temporal integrators that strictly maintain the equation of state constraint. The resulting spatio-temporal discretization is second-order accurate deterministically and maintains fluctuation-dissipation balance in the linearized stochastic equations. We apply our algorithms to model the development of giant concentration fluctuations in the presence of concentration gradients, and investigate the validity of common simplifications such as neglecting the spatial non-homogeneity of density and transport properties. We perform simulations of diffusive mixing of two fluids of different densities in two dimensions and compare the results of low Mach number continuum simulations to hard-disk molecular dynamics simulations. Excellent agreement is observed between the particle and continuum simulations of giant fluctuations during time-dependent diffusive mixing.

  19. Design of an electromagnetic accelerator for turbulent hydrodynamic mix studies

    SciTech Connect (OSTI)

    Susoeff, A.R.; Hawke, R.S.; Morrison, J.J.; Dimonte, G.; Remington, B.A.

    1993-12-08T23:59:59.000Z

    An electromagnetic accelerator in the form of a linear electric motor (LEM) has been designed to achieve controlled acceleration profiles of a carriage containing hydrodynamically unstable fluids for the investigation of the development of turbulent mix. The Rayleigh- Taylor instability is investigated by accelerating two dissimilar density fluids using the LEM to achieve a wide variety of acceleration and deceleration profiles. The acceleration profiles are achieved by independent control of rail and augmentation currents. A variety of acceleration-time profiles are possible including: (1) constant, (2) impulsive and (3) shaped. The LEM and support structure are a robust design in order to withstand high loads with deflections and to mitigate operational vibration. Vibration of the carriage during acceleration could create artifacts in the data which would interfere with the intended study of the Rayleigh-Taylor instability. The design allows clear access for diagnostic techniques such as laser induced fluorescence radiography, shadowgraphs and particle imaging velocimetry. Electromagnetic modeling codes were used to optimize the rail and augmentation coil positions within the support structure framework. Results of contemporary studies for non-arcing sliding contact of solid armatures are used for the design of the driving armature and the dynamic electromagnetic braking system. A 0. 6MJ electrolytic capacitor bank is used for energy storage to drive the LEM. This report will discuss a LEM design which will accelerate masses of up to 3kg to a maximum of about 3000g{sub o}, where g{sub o} is accelerated due to gravity.

  20. MODEST: modeling stellar evolution and (hydro)dynamics

    E-Print Network [OSTI]

    Piet Hut

    2003-09-15T23:59:59.000Z

    Simulations of dense stellar systems currently face two major hurdles, one astrophysical and one computational. The astrophysical problem lies in the fact that several major stages in binary evolution, such as common envelope evolution, are still poorly understood. The best we can do in these cases is to parametrize our ignorance, in a way that is reminiscent of the introduction of a mixing length to describe convection in a single star, or an alpha parameter in modeling an accretion disk. The hope is that by modeling a whole star cluster in great detail, and comparing the results to the wealth of observational data currently available, we will be able to constrain the parameters that capture the unknown physics. The computational problem is one of composition: while we have accurate computer codes for modeling stellar dynamics, stellar hydrodynamics, and stellar evolution, we currently have no good way to put all this knowledge together in a single software environment. A year ago, a loosely-knit organization was founded to address these problems, MODEST for MOdeling DEnse STellar systems, with nine working groups and a series of meetings that are held every half year. This report reviews the first year of this initiative. Much more detail can be found on the MODEST web site http://www.manybody.org/modest.html .

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

    E-Print Network [OSTI]

    Tiezheng Qian; Xiao-Ping Wang

    2004-03-06T23:59:59.000Z

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

  2. Onset and cessation of motion in hydrodynamically sheared granular beds

    E-Print Network [OSTI]

    Abram H. Clark; Mark D. Shattuck; Nicholas T. Ouellette; Corey S. O'Hern

    2015-04-14T23:59:59.000Z

    To clarify the grain-scale mechanisms that control the onset and cessation of sediment transport, we performed molecular dynamics simulations of granular beds driven by a model hydrodynamic shear flow. We find a critical value for the Shields number (the nondimensional shear stress at the top of the granular bed) that separates flowing and static states, with a bed flow rate that is discontinuous at the critical value. The transition times between flowing and static states diverge as the system approaches the critical Shields number from above and below. Additionally we find that, for finite systems, the onset of flow occurs stochastically at supercritical Shields numbers. We show that the statistics of the Shields number at failure obey Weibullian weakest-link statistics, and that the onset of flow is caused by local grain rearrangements that give rise to additional rearrangements and then to continuous flow. Thus, the onset of motion is governed by the packing structure of the granular bed, even deep beneath the surface. Since the fluid dynamics is strongly coupled to the settling process and thus to the bed structure, this also suggests a strong feedback between the fluid dynamics and granular physics in bed mobilization.

  3. Hybrid magneto-hydrodynamic simulation of a driven FRC

    SciTech Connect (OSTI)

    Rahman, H. U., E-mail: hrahman@trialphaenergy.com; Wessel, F. J.; Binderbauer, M. W.; Qerushi, A.; Rostoker, N. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States)] [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States); Conti, F. [Physics Department “E. Fermi,” University of Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy) [Physics Department “E. Fermi,” University of Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Plasma Diagnostics and Technologies Ltd., Via Giuntini 63, 56023 Navacchio (PI) (Italy); Ney, P. [Mount San Jacinto College, Menifee, California 92584 (United States)] [Mount San Jacinto College, Menifee, California 92584 (United States)

    2014-03-15T23:59:59.000Z

    We simulate a field-reversed configuration (FRC), produced by an “inductively driven” FRC experiment; comprised of a central-flux coil and exterior-limiter coil. To account for the plasma kinetic behavior, a standard 2-dimensional magneto-hydrodynamic code is modified to preserve the azimuthal, two-fluid behavior. Simulations are run for the FRC's full-time history, sufficient to include: acceleration, formation, current neutralization, compression, and decay. At start-up, a net ion current develops that modifies the applied-magnetic field forming closed-field lines and a region of null-magnetic field (i.e., a FRC). After closed-field lines form, ion-electron drag increases the electron current, canceling a portion of the ion current. The equilibrium is lost as the total current eventually dissipates. The time evolution and magnitudes of the computed current, ion-rotation velocity, and plasma temperature agree with the experiments, as do the rigid-rotor-like, radial-profiles for the density and axial-magnetic field [cf. Conti et al. Phys. Plasmas 21, 022511 (2014)].

  4. Radiation Hydrodynamical Evolution of Primordial H II Regions

    E-Print Network [OSTI]

    Daniel Whalen; Tom Abel; Michael L. Norman

    2004-03-02T23:59:59.000Z

    We simulate the ionization environment of z ~ 20 luminous objects formed within the framework of the current CDM cosmology and compute their UV escape fraction. These objects are likely single very massive stars that are copious UV emitters. We present analytical estimates as well as one--dimensional radiation hydrodynamical calculations of the evolution of these first HII regions in the universe. The initially D--type ionization front evolves to become R--type within $\\lesssim 10^5$ yrs at a distance $\\sim1$ pc. This ionization front then completely overruns the halo, accelerating an expanding shell of gas outward to velocities in excess of 30 km s$^{-1}$, about ten times the escape velocity of the confining dark matter halo. We find that the evolution of the HII region depends only weakly on the assumed stellar ionizing luminosities. Consequently, most of the gas surrounding the first stars will leave the dark halo whether or not the stars produce supernovae. If they form the first massive seed black holes these are unlikely to accrete within a Hubble time after they formed until they are incorporated into larger dark matter halos that contain more gas. Because these I--fronts exit the halo on timescales much shorter than the stars' main sequence lifetimes their host halos have UV escape fractions of $\\gtrsim 0.95$, fixing an important parameter for theoretical studies of cosmological hydrogen reionization.

  5. Hydrodynamical Simulations of Nuclear Rings in Barred Galaxies

    E-Print Network [OSTI]

    Li, Zhi; Kim, Woong-Tae

    2015-01-01T23:59:59.000Z

    Dust lanes, nuclear rings, and nuclear spirals are typical gas structures in the inner region of barred galaxies Their shapes and properties are linked to the physical parameters of the host galaxy. We use high-resolution hydrodynamical simulations to study 2D gas flows in simple barred galaxy models. The nuclear rings formed in our simulations can be divided into two groups: one group is nearly round and the other is highly elongated. We find that roundish rings may not form when the bar pattern speed is too high or the bulge central density is too low. We also study the periodic orbits in our galaxy models, and find that the concept of inner Lindblad resonance (ILR) may be generalized by the extent of $x_2$ orbits. All roundish nuclear rings in our simulations settle in the range of $x_2$ orbits (or ILRs). However, knowing the resonances is insufficient to pin down the exact location of these nuclear rings. We suggest that the backbone of round nuclear rings is the $x_2$ orbital family, i.e. round nuclear r...

  6. Hydrodynamical model for $J/?$ suppression and elliptic flow

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2009-10-06T23:59:59.000Z

    In a hydrodynamic model, we have studied $J/\\psi$ suppression and elliptic flow in Au+Au collisions at RHIC energy $\\sqrt{s}$=200 GeV. At the initial time, $J/\\psi$'s are randomly distributed in the fluid. As the fluid evolve in time, the free streaming $J/\\psi$'s are dissolved if the local fluid temperature exceeds a melting temperature $T_{J/\\psi}$. Sequential melting of charmonium states ($\\chi_c$, $\\psi\\prime$ and $J/\\psi$), with melting temperatures $T_{\\chi_c}=T_{\\psi\\prime} \\approx 1.2T_c$, $T_{J/\\psi} \\approx2T_c$ and feed-down fraction $F\\approx 0.3$, is consistent with the PHENIX data on $J/\\psi$ suppression and near zero elliptic flow for $J/\\psi$'s. It is also shown that the model will require substantial regeneration of charmoniums, if the charmonium states dissolve at temperature close to the critical temperature, $T_{\\chi_c}=T_{\\psi\\prime} \\leq T_c$, $T_{J/\\psi}\\approx1.2T_c$. The regenerated charmoniums will have positive elliptic flow.

  7. The chemical enrichment of the ICM from hydrodynamical simulations

    E-Print Network [OSTI]

    S. Borgani; D. Fabjan; L. Tornatore; S. Schindler; K. Dolag; A. Diaferio

    2008-01-07T23:59:59.000Z

    The study of the metal enrichment of the intra-cluster and inter-galactic media (ICM and IGM) represents a direct means to reconstruct the past history of star formation, the role of feedback processes and the gas-dynamical processes which determine the evolution of the cosmic baryons. In this paper we review the approaches that have been followed so far to model the enrichment of the ICM in a cosmological context. While our presentation will be focused on the role played by hydrodynamical simulations, we will also discuss other approaches based on semi-analytical models of galaxy formation, also critically discussing pros and cons of the different methods. We will first review the concept of the model of chemical evolution to be implemented in any chemo-dynamical description. We will emphasise how the predictions of this model critically depend on the choice of the stellar initial mass function, on the stellar life-times and on the stellar yields. We will then overview the comparisons presented so far between X-ray observations of the ICM enrichment and model predictions. We will show how the most recent chemo-dynamical models are able to capture the basic features of the observed metal content of the ICM and its evolution. We will conclude by highlighting the open questions in this study and the direction of improvements for cosmological chemo-dynamical models of the next generation.

  8. A new pressure relaxation closure model for two%3CU%2B2010%3Ematerial lagrangian hydrodynamics.

    SciTech Connect (OSTI)

    Rider, William J.; Shashkov, Mikhail J. (Los Alamos National Laboratory, Los Alamos, NM); Kamm, James R.

    2010-05-01T23:59:59.000Z

    We present a new model for closing a system of Lagrangian hydrodynamics equations for a two-material cell with a single velocity model. We describe a new approach that is motivated by earlier work of Delov and Sadchikov and of Goncharov and Yanilkin. Using a linearized Riemann problem to initialize volume fraction changes, we require that each material satisfy its own pdV equation, which breaks the overall energy balance in the mixed cell. To enforce this balance, we redistribute the energy discrepancy by assuming that the corresponding pressure change in each material is equal. This multiple-material model is packaged as part of a two-step time integration scheme. We compare results of our approach with other models and with corresponding pure-material calculations, on two-material test problems with ideal-gas or stiffened-gas equations of state.

  9. Hydrodynamic flow in Lower Cretaceous Muddy Sandstones, Rozet Field, Powder River Basin, Wyoming

    E-Print Network [OSTI]

    Smith, David Arthur

    1984-01-01T23:59:59.000Z

    /km) across the field yields a hydrodynamic oil column of 420 ft (128 m). Capillary pressure differences due to permeability changes account for a oil column of 72 ft (42 m). The combined capillary and hydrodynamic oil columns of 492 ft (150 m) compares... and other Muddy Formation oil fields. Contour interval 1000 ft (305 m). . . Regional east-west cross section showing variable sandstone development in the Muddy interval from Kitty to Rozet Fields. . . . . . . . . Diagrammatic environments the northern...

  10. Hydrodynamics of the Mission Canyon Formation in the Billings Nose area, North Dakota

    E-Print Network [OSTI]

    Mitsdarffer, Alan Ray

    1985-01-01T23:59:59.000Z

    and associated highlands of central Montana (Fish and Kinard, 1959). Hydrodynamic flow was considered as a possible cause for the observed tilted oil-water contact for the Nottingham field in Saskatchewan, but the direction of tilt was opposite to flow... conditions with low gradients similiar to that depicted by the regional map. The present hydrodynamic conditions result from the recent invasion of the field area by the fresher ~ster lens. The oil accumulation will eventually be flushed from the area...

  11. Hydrodynamics of bubble columns with application to Fischer-Tropsch synthesis

    E-Print Network [OSTI]

    Raphael, Matheo Lue

    1988-01-01T23:59:59.000Z

    HYDRODYNAMICS OF BUBBLE COLUMNS AYITH APPLICATION TO FISCHER-TROPSCH SYNTHESIS A Thesis by- MATHEO LUE RAPHAEL Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1988 Major Subject: Chemical Engineering HYDRODYNAMICS OF BUBBLE COLUMNS WITH APPLICATION TO FISCHER-TROPSCH SYNTHESIS A Thesis by iAIATHEO LUE RAPHAEL Approved as to style and content by: D. B. Bukur Chairman of Com 'ttee) M. T. za...

  12. Depositional environment and hydrodynamic flow in Lower Cretaceous J Sandstone, Lonetree field, Denver basin, Colorado

    E-Print Network [OSTI]

    Bicknell, James Scott

    1985-01-01T23:59:59.000Z

    DEPOSITIONAL ENVIRONMENT AND HYDRODYNAMIC FLOW IN LOWER CRETACEOUS J SANDSTONE, LONETREE FIELD, DENVER BASIN, COLORADO A Thesis by JAMES SCOTT BICKNELL Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE December 1985 Major Subject: Geology DEPOSITIONAL ENVIRONMENT AND HYDRODYNAMIC FLOW IN LOWER CRETACEOUS J SANDSTONE, LONETREE FIELD, DENVER BASIN, COLORADO A Thesis by JAMES SCOTT BICKNELL Approved...

  13. An Open-Source Neutrino Radiation Hydrodynamics Code for Core-Collapse Supernovae

    E-Print Network [OSTI]

    Evan O'Connor

    2014-11-25T23:59:59.000Z

    We present an open-source update to the spherically-symmetric, general-relativistic hydrodynamics, core-collapse supernova (CCSN) code GR1D (O'Connor & Ott, 2010, CQG, 27, 114103). The source code is available at http://www.GR1Dcode.org. We extend its capabilities to include a general relativistic treatment of neutrino transport based on the moment formalisms of Shibata et al., 2011, PTP, 125, 1255 and Cardall et al., 2013, PRD, 87 103004. We pay special attention to implementing and testing numerical methods and approximations that lessen the computational demand of the transport scheme by removing the need to invert large matrices. This is especially important for the implementation and development of moment-like transport methods in two and three dimensions. A critical component of neutrino transport calculations are the neutrino-matter interaction coefficients that describe the production, absorption, scattering, and annihilation of neutrinos. In this article we also describe our open-source, neutrino interaction library NuLib (available at http://www.nulib.org). We believe that an open-source approach to describing these interactions is one of the major steps needed to progress towards robust models of CCSNe and robust predictions of the neutrino signal. We show, via comparisons to full Boltzmann neutrino transport simulations of CCSNe, that our neutrino transport code performs remarkably well. Furthermore, we show that the methods and approximations we employ to increase efficiency do not decrease the fidelity of our results. We also test the ability of our general relativistic transport code to model failed CCSN by evolving a 40 solar-mass progenitor to the onset of collapse to a black hole.

  14. Density Power Spectrum of Compressible Hydrodynamic Turbulent Flows

    E-Print Network [OSTI]

    Jongsoo Kim; Dongsu Ryu

    2005-07-26T23:59:59.000Z

    Turbulent flows are ubiquitous in astrophysical environments, and understanding density structures and their statistics in turbulent media is of great importance in astrophysics. In this paper, we study the density power spectra, $P_{\\rho}$, of transonic and supersonic turbulent flows through one and three-dimensional simulations of driven, isothermal hydrodynamic turbulence with root-mean-square Mach number in the range of $1 \\la M_{\\rm rms} \\la 10$. From one-dimensional experiments we find that the slope of the density power spectra becomes gradually shallower as the rms Mach number increases. It is because the density distribution transforms from the profile with {\\it discontinuities} having $P_{\\rho} \\propto k^{-2}$ for $M_{\\rm rms} \\sim 1$ to the profile with {\\it peaks} having $P_{\\rho} \\propto k^0$ for $M_{\\rm rms} \\gg 1$. We also find that the same trend is carried to three-dimension; that is, the density power spectrum flattens as the Mach number increases. But the density power spectrum of the flow with $M_{\\rm rms} \\sim 1$ has the Kolmogorov slope. The flattening is the consequence of the dominant density structures of {\\it filaments} and {\\it sheets}. Observations have claimed different slopes of density power spectra for electron density and cold H I gas in the interstellar medium. We argue that while the Kolmogorov spectrum for electron density reflects the {\\it transonic} turbulence of $M_{\\rm rms} \\sim 1$ in the warm ionized medium, the shallower spectrum of cold H I gas reflects the {\\it supersonic} turbulence of $M_{\\rm rms} \\sim$ a few in the cold neutral medium.

  15. Preparing for an explosion: Hydrodynamic instabilities and turbulence in presupernovae

    SciTech Connect (OSTI)

    Smith, Nathan; Arnett, W. David, E-mail: nathans@as.arizona.edu, E-mail: darnett@as.arizona.edu [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)

    2014-04-20T23:59:59.000Z

    Both observations and numerical simulations are discordant with predictions of conventional stellar evolution codes for the latest stages of a massive star's life before core collapse. The most dramatic example of this disconnect is in the eruptive mass loss occurring in the decade preceding Type IIn supernovae. We outline the key empirical evidence that indicates severe pre-supernova instability in massive stars, and we suggest that the chief reason that these outbursts are absent in stellar evolution models may lie in the treatment of turbulent convection in these codes. The mixing length theory that is used ignores (1) finite amplitude fluctuations in velocity and temperature and (2) their nonlinear interaction with nuclear burning. Including these fluctuations is likely to give rise to hydrodynamic instabilities in the latest burning sequences, which prompts us to discuss a number of far-reaching implications for the fates of massive stars. In particular, we explore connections to enhanced pre-supernova mass loss, unsteady nuclear burning and consequent eruptions, swelling of the stellar radius that may trigger violent interactions with a companion star, and potential modifications to the core structure that could dramatically alter calculations of the core-collapse explosion mechanism itself. These modifications may also impact detailed nucleosynthesis and measured isotopic anomalies in meteorites, as well as the interpretation of young core-collapse supernova remnants. Understanding these critical instabilities in the final stages of evolution may make possible the development of an early warning system for impending core collapse, if we can identify their asteroseismological or eruptive signatures.

  16. RIS-M-2440 JD/as ASSESSMENT OF FAST RADIOGRAPHIC SYSTEMS

    E-Print Network [OSTI]

    fied, single-tank) used for radiography of 10 mm Fe plate Fig. 3. ISO wire IQI's and ASTM penetrameters as fluorometalllic screens were tested and compared. ISO wire IQI's and ASTM penetrameters were used together with 30 single-tank) used for radiography of 30 mm Al plate Fig. 2. Andrex 300-kV X-ray machine (self-recti- 11

  17. Simulation and Analysis of Converging Shock Wave Test Problems

    SciTech Connect (OSTI)

    Ramsey, Scott D. [Los Alamos National Laboratory; Shashkov, Mikhail J. [Los Alamos National Laboratory

    2012-06-21T23:59:59.000Z

    Results and analysis pertaining to the simulation of the Guderley converging shock wave test problem (and associated code verification hydrodynamics test problems involving converging shock waves) in the LANL ASC radiation-hydrodynamics code xRAGE are presented. One-dimensional (1D) spherical and two-dimensional (2D) axi-symmetric geometric setups are utilized and evaluated in this study, as is an instantiation of the xRAGE adaptive mesh refinement capability. For the 2D simulations, a 'Surrogate Guderley' test problem is developed and used to obviate subtleties inherent to the true Guderley solution's initialization on a square grid, while still maintaining a high degree of fidelity to the original problem, and minimally straining the general credibility of associated analysis and conclusions.

  18. The DARHTAcquisition, Archival, Analysis, And Instrument Control System (DAAAC), And Network Infrastructure

    SciTech Connect (OSTI)

    Archuleta, Rita Denise [Los Alamos National Laboratory; Sanchez, Lawrence [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    The Dual Axis Radiographic Hydrodynamic Test Facility (DARHT) at Los Alamos National Laboratory is the world's most advanced weapons test facility. DARHT contains two linear accelerators for producing flash radiographs of hydrodynamic experiments. High-speed electronics and optical instrumentation are used for triggering the accelerators and collecting accelerator data. Efficient and effective diagnostics provide basic information needed to routinely tune the accelerators for peak radiographic performance, and to successfully monitor the accelerators performance. DARHT's server and network infrastructure is a key element in providing shot related data storage and retrieval for successfully executing radiographic experiments. This paper will outline the elaborate Data Acquisition, Archival, Analysis, and Instrument Control System (DAAAC), as well as the server and network infrastructure for both accelerators.

  19. Development of Fully Coupled Aeroelastic and Hydrodynamic Models for Offshore Wind Turbines: Preprint

    SciTech Connect (OSTI)

    Jonkman, J. M.; Sclavounos, P. D.

    2006-01-01T23:59:59.000Z

    Aeroelastic simulation tools are routinely used to design and analyze onshore wind turbines, in order to obtain cost effective machines that achieve favorable performance while maintaining structural integrity. These tools employ sophisticated models of wind-inflow; aerodynamic, gravitational, and inertial loading of the rotor, nacelle, and tower; elastic effects within and between components; and mechanical actuation and electrical responses of the generator and of control and protection systems. For offshore wind turbines, additional models of the hydrodynamic loading in regular and irregular seas, the dynamic coupling between the support platform motions and wind turbine motions, and the dynamic characterization of mooring systems for compliant floating platforms are also important. Hydrodynamic loading includes contributions from hydrostatics, wave radiation, and wave scattering, including free surface memory effects. The integration of all of these models into comprehensive simulation tools, capable of modeling the fully coupled aeroelastic and hydrodynamic responses of floating offshore wind turbines, is presented.

  20. Asymmetric (1+1)-dimensional hydrodynamics in high-energy collisions

    SciTech Connect (OSTI)

    Bialas, A. [H. Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, PL-30-059 Krakow, Poland and M. Smoluchowski Institute of Physics, Jagellonian University, Reymonta 4, PL-30-059 Krakow (Poland); Peschanski, R. [Institut de Physique Theorique, CEA-Saclay, F-91191 Gif-sur-Yvette Cedex (France)

    2011-05-15T23:59:59.000Z

    The possibility that particle production in high-energy collisions is a result of two asymmetric hydrodynamic flows is investigated using the Khalatnikov form of the (1+1)-dimensional approximation of hydrodynamic equations. The general solution is discussed and applied to the physically appealing ''generalized in-out cascade'' where the space-time and energy-momentum rapidities are equal at initial temperature but boost invariance is not imposed. It is demonstrated that the two-bump structure of the entropy density, characteristic of the asymmetric input, changes easily into a single broad maximum compatible with data on particle production in symmetric processes. A possible microscopic QCD interpretation of asymmetric hydrodynamics is proposed.

  1. Calibration curves for some standard Gap Tests

    SciTech Connect (OSTI)

    Bowman, A.L.; Sommer, S.C.

    1989-01-01T23:59:59.000Z

    The relative shock sensitivities of explosive compositions are commonly assessed using a family of experiments that can be described by the generic term ''Gap Test.'' Gap tests include a donor charge, a test sample, and a spacer, or gap, between two explosives charges. The donor charge, gap material, and test dimensions are held constant within each different version of the gap test. The thickness of the gap is then varied to find the value at which 50% of the test samples will detonate. The gap tests measure the ease with a high-order detonation can be established in the test explosive, or the ''detonability,'' of the explosive. Test results are best reported in terms of the gap thickness at the 50% point. It is also useful to define the shock pressure transmitted into the test sample at the detonation threshold. This requires calibrating the gap test in terms of shock pressure in the gap as a function of the gap thickness. It also requires a knowledge of the shock Hugoniot of the sample explosive. We used the 2DE reactive hydrodynamic code with Forest Fire burn rates for the donor explosives to calculate calibration curves for several gap tests. The model calculations give pressure and particle velocity on the centerline of the experimental set-up and provide information about the curvature and pulse width of the shock wave. 10 refs., 1 fig.

  2. Potential climate change effects on Great Lakes hydrodynamics and water quality

    SciTech Connect (OSTI)

    Lam, D.C.L.; Schertzer, W.M. [eds.

    1999-07-01T23:59:59.000Z

    The problem of climate change has become increasingly recognized as a major environmental concern. Its impact can affect many socio-economic and ecosystem components. This book provides a state-of-the-art review of the climate change effects on lake hydrodynamics and water quality. Most of the engineering cases covered deal with the ability of existing infrastructure to cope with extreme weather conditions. The aim is to provide sufficient case studies to illustrate the advancement in modeling research on lake hydrodynamics, thermal stratification, pollutant transport and water quality by highlighting the climate change aspects in the application of these techniques.

  3. Temperature-extrapolation method for Implicit Monte Carlo - Radiation hydrodynamics calculations

    SciTech Connect (OSTI)

    McClarren, R. G. [Department of Nuclear Engineering, Texas A and M University, 3133 TAMU, College Station, TX 77802 (United States); Urbatsch, T. J. [XTD-5: Air Force Systems, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 77845 (United States)

    2013-07-01T23:59:59.000Z

    We present a method for implementing temperature extrapolation in Implicit Monte Carlo solutions to radiation hydrodynamics problems. The method is based on a BDF-2 type integration to estimate a change in material temperature over a time step. We present results for radiation only problems in an infinite medium and for a 2-D Cartesian hohlraum problem. Additionally, radiation hydrodynamics simulations are presented for an RZ hohlraum problem and a related 3D problem. Our results indicate that improvements in noise and general behavior are possible. We present considerations for future investigations and implementations. (authors)

  4. Statistical Estimation of Two-Body Hydrodynamic Properties Using System Identification

    E-Print Network [OSTI]

    Xie, Chen

    2010-01-14T23:59:59.000Z

    of Liquid Natural Gas (LNG). The offloading operations from the LNG terminal to the LNG carrier are conditioned by the arm-length of LNG off-loading lines and are also somewhat constrained by the fragility of the transportation lines due to extreme low... the hydrodynamic interaction effects in both the first order motions and the mean second order drift forces on a pair of closely positioned FPSO and LNG carrier. It was shown that the simplification of using free floating single body hydrodynamics to study...

  5. Hydrodynamics and heat transfer aspects of corium-water interactions: Interim report

    SciTech Connect (OSTI)

    Spencer, B.W.; Sienicki, J.J.; McUmber, L.M.

    1987-03-01T23:59:59.000Z

    The results of reactor-material experiments are described in which molten corium entered a scaled mock-up of the reactor cavity region of a PWR containment. The experiments address ex-vessel cavity interactions such as corium quench and steam generation rates (for those cases in which water is present in the cavity), hydrodynamic dispersal of water and corim from the cavity, hydrogen generation, containment atmosphere heatup by dispersed corium, and debris characterization. Generic aspects of corium/water mixing, fragmentation, and quench were also investigated. The results include extensive modeling of the hydrodynamic and heat transfer processes and application of the models to the full size reactor system.

  6. Di-jet hadron pair correlation in a hydrodynamical model with a quenching jet

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2008-01-15T23:59:59.000Z

    In jet quenching, a hard QCD parton, before fragmenting into a jet of hadrons, deposits a fraction of its energy in the medium, leading to suppressed production of high-$p_T$ hadrons. Assuming that the deposited energy quickly thermalizes, we simulate the subsequent hydrodynamic evolution of the QGP fluid. Hydrodynamic evolution and subsequent particle emission depend on the jet trajectories. Azimuthal distribution of excess $\\pi^-$ due to quenching jet, averaged over all the trajectories, reasonably well reproduce the di-hadron correlation as measured by the STAR and PHENIX collaboration in central and in peripheral Au+Au collisions.

  7. Spin current evolution in the separated spin-up and spin-down quantum hydrodynamics

    E-Print Network [OSTI]

    Trukhanova, Mariya Iv

    2015-01-01T23:59:59.000Z

    We have developed the quantum hydrodynamic model that describes particles with spin-up and with spin-down in separate. We have derived the equation of the spin current evolution as a part of the set of the quantum hydrodynamics (QHD) equations that treat particles with different projection of spin on the preferable direction as two different species. We have studied orthogonal propagation of waves in the external magnetic field and determined the contribution of quantum corrections due to the Bohm potential and to magnetization energy of particles with different projections of spin in the spin current wave dispersion. We have analyzed the limits of weak and strong magnetic fields.

  8. Reliable estimation of shock position in shock-capturing compressible hydrodynamics codes

    SciTech Connect (OSTI)

    Nelson, Eric M [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    The displacement method for estimating shock position in a shock-capturing compressible hydrodynamics code is introduced. Common estimates use simulation data within the captured shock, but the displacement method uses data behind the shock, making the estimate consistent with and as reliable as estimates of material parameters obtained from averages or fits behind the shock. The displacement method is described in the context of a steady shock in a one-dimensional lagrangian hydrodynamics code, and demonstrated on a piston problem and a spherical blast wave.The displacement method's estimates of shock position are much better than common estimates in such applications.

  9. RMOTC - Testing

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

    Sale of Equipment and Materials DOE to Sell NPR-3 Testing Tomorrow's Technology Today RMOTC - Testing - From Lab to Industry, Moving Your Ideas Forward RMOTC provides a neutral,...

  10. Investigation of oil injection into brine for the Strategic Petroleum Reserve : hydrodynamics and mixing experiments with SPR liquids.

    SciTech Connect (OSTI)

    Castaneda, Jaime N.; Cote, Raymond O.; Torczynski, John Robert; O'Hern, Timothy John

    2004-05-01T23:59:59.000Z

    An experimental program was conducted to study a proposed approach for oil reintroduction in the Strategic Petroleum Reserve (SPR). The goal was to assess whether useful oil is rendered unusable through formation of a stable oil-brine emulsion during reintroduction of degassed oil into the brine layer in storage caverns. An earlier report (O'Hern et al., 2003) documented the first stage of the program, in which simulant liquids were used to characterize the buoyant plume that is produced when a jet of crude oil is injected downward into brine. This report documents the final two test series. In the first, the plume hydrodynamics experiments were completed using SPR oil, brine, and sludge. In the second, oil reinjection into brine was run for approximately 6 hours, and sampling of oil, sludge, and brine was performed over the next 3 months so that the long-term effects of oil-sludge mixing could be assessed. For both series, the experiment consisted of a large transparent vessel that is a scale model of the proposed oil-injection process at the SPR. For the plume hydrodynamics experiments, an oil layer was floated on top of a brine layer in the first test series and on top of a sludge layer residing above the brine in the second test series. The oil was injected downward through a tube into the brine at a prescribed depth below the oil-brine or sludge-brine interface. Flow rates were determined by scaling to match the ratio of buoyancy to momentum between the experiment and the SPR. Initially, the momentum of the flow produces a downward jet of oil below the tube end. Subsequently, the oil breaks up into droplets due to shear forces, buoyancy dominates the flow, and a plume of oil droplets rises to the interface. The interface was deflected upward by the impinging oil-brine plume. Videos of this flow were recorded for scaled flow rates that bracket the equivalent pumping rates in an SPR cavern during injection of degassed oil. Image-processing analyses were performed to quantify the penetration depth and width of the oil jet. The measured penetration depths were shallow, as predicted by penetration-depth models, in agreement with the assumption that the flow is buoyancy-dominated, rather than momentum-dominated. The turbulent penetration depth model overpredicted the measured values. Both the oil-brine and oil-sludge-brine systems produced plumes with hydrodynamic characteristics similar to the simulant liquids previously examined, except that the penetration depth was 5-10% longer for the crude oil. An unexpected observation was that centimeter-size oil 'bubbles' (thin oil shells completely filled with brine) were produced in large quantities during oil injection. The mixing experiments also used layers of oil, sludge, and brine from the SPR. Oil was injected at a scaled flow rate corresponding to the nominal SPR oil injection rates. Injection was performed for about 6 hours and was stopped when it was evident that brine was being ingested by the oil withdrawal pump. Sampling probes located throughout the oil, sludge, and brine layers were used to withdraw samples before, during, and after the run. The data show that strong mixing caused the water content in the oil layer to increase sharply during oil injection but that the water content in the oil dropped back to less than 0.5% within 16 hours after injection was terminated. On the other hand, the sediment content in the oil indicated that the sludge and oil appeared to be well mixed. The sediment settled slowly but the oil had not returned to the baseline, as-received, sediment values after approximately 2200 hours (3 months). Ash content analysis indicated that the sediment measured during oil analysis was primarily organic.

  11. Simplified 1-D Hydrodynamic and Salinity Transport Modeling of the Sacramento–San Joaquin Delta: Sea Level Rise and Water Diversion Effects

    E-Print Network [OSTI]

    Fleenor, William E.; Bombardelli, Fabian

    2013-01-01T23:59:59.000Z

    Hydrodynamic and Salinity Transport Modeling of the Sacramento–San Joaquin Delta: Sea Level Rise and Water Diversion Effects

  12. An efficient immersed boundary-lattice Boltzmann method for the hydrodynamic interaction of elastic filaments

    E-Print Network [OSTI]

    Luo, Haoxiang

    An efficient immersed boundary-lattice Boltzmann method for the hydrodynamic interaction of elastic flapping in the Kármán gait and the entrainment regions near a cylinder is studied to model fish swimming in these regions. Significant drag reduction is found for the filament, and the result is consistent

  13. EFFECTS OF CHAMBER GEOMETRY AND GAS PROPERTIES ON HYDRODYNAMIC EVOLUTION OF IFE Zoran Dragojlovic1

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    -rays and ions travel through the chamber and deposit some of their energy in the chamber background gas; the effects of various heat sources and transfer mechanisms such as photon and ion heat deposition and chamberEFFECTS OF CHAMBER GEOMETRY AND GAS PROPERTIES ON HYDRODYNAMIC EVOLUTION OF IFE CHAMBERS Zoran

  14. Anomalous Microfluidic Phonons Induced by the Interplay of Hydrodynamic Screening and Incompressibility

    E-Print Network [OSTI]

    Tlusty, Tsvi

    Anomalous Microfluidic Phonons Induced by the Interplay of Hydrodynamic Screening the acoustic normal modes (``phonons'') of a 1D microfluidic droplet crystal at the crossover between 2D flow.55.Dÿ, 47.60.+i, 47.63.mf, 63.22.+m Microfluidic two-phase flow offers experimental tools to investigate

  15. Hydrodynamic forces and surface topography: Centimeter-scale spatial variation in wave forces

    E-Print Network [OSTI]

    Denny, Mark

    Hydrodynamic forces and surface topography: Centimeter-scale spatial variation in wave forces. On the rugose rock surfaces of wave-swept shores, interactions between substratum topography and wave-induced flow may create such a spatially variable environment. Topography Numerous investigators have explored

  16. XXII ICTAM, 2529 August 2008, Adelaide, Australia PERISTALSIS AND HYDRODYNAMIC INSTABILITIES

    E-Print Network [OSTI]

    Hoepffner, Jérôme

    in hydrodynamic instabilities. A propagating wall deformation generates pressure gradients in the flow, which act channel has its height reduced as if locally constricted by a cuff, sliding towards the right. The wall to the propagation of the constricted region, a high pressure is generated in P1 where the fluid is pushed down

  17. Core-annular flow through a horizontal pipe: Hydrodynamic counterbalancing of buoyancy force on core

    E-Print Network [OSTI]

    Vuik, Kees

    Core-annular flow through a horizontal pipe: Hydrodynamic counterbalancing of buoyancy force of a high-viscosity liquid core surrounded by a low-viscosity liquid annular layer through a horizontal pipe through a horizontal pipe. Since the densities of the two liq- uids are almost always different, gravity

  18. GENERIC HYDRODYNAMIC INSTABILITY OF CURL EIGENFIELDS JOHN ETNYRE AND ROBERT GHRIST

    E-Print Network [OSTI]

    Ghrist, Robert W.

    GENERIC HYDRODYNAMIC INSTABILITY OF CURL EIGENFIELDS JOHN ETNYRE AND ROBERT GHRIST ABSTRACT. We prove that for generic geometry, the curl-eigenfield solutions to the steady Euler equations on R3 /Z3 class of flows -- the curl eigenfields -- which form the most fascinating and challenging steady

  19. Porous Superhydrophobic Membranes: Hydrodynamic Anomaly in Oscillating Flows S. Rajauria,1,2

    E-Print Network [OSTI]

    that a stable Knudsen layer of gas percolates on the membrane, changing the boundary condition. This is be simultaneously. Oscillatory hydrodynamic measurements on porous superhydropho- bic membranes as a function of Ès Knudsen layer of air at the interface. DOI: 10.1103/PhysRevLett.107.174501 PACS numbers: 47.61.Àk, 47

  20. Viscosity of Bacterial Suspensions: Hydrodynamic Interactions and Self-Induced Noise Shawn D. Ryan,1, 2

    E-Print Network [OSTI]

    Berlyand, Leonid

    Viscosity of Bacterial Suspensions: Hydrodynamic Interactions and Self-Induced Noise Shawn D. Ryan, 2011) The viscosity of a suspension of swimming bacteria is investigated analytically and numerically fluid, result in a dramatic reduction of the effective viscosity. In agreement with experiments

  1. Petascale Algorithms for Reactor Hydrodynamics Paul Fischer, James Lottes, David Pointer, and Andew Siegel

    E-Print Network [OSTI]

    Fischer, Paul F.

    -averaged Navier- Stokes) and subchannel models. Our initial study is focused on LES of sodium-cooled fast reactorPetascale Algorithms for Reactor Hydrodynamics Paul Fischer, James Lottes, David Pointer, and Andew describe recent algorithmic developments that have enabled large eddy simulations of reactor flows on up

  2. A microfluidic-based hydrodynamic trap: design and implementation Melikhan Tanyeri,a

    E-Print Network [OSTI]

    Schroeder, Charles

    A microfluidic-based hydrodynamic trap: design and implementation Melikhan Tanyeri,a Mikhil Ranka: 10.1039/c0lc00709a We report an integrated microfluidic device for fine-scale manipulation in a monolithic PDMS-based microfluidic device. In this work, we characterize device design parameters enabling

  3. Hydrodynamic and Structural Performance of the Transverse Horizontal Axis Water Turbine

    E-Print Network [OSTI]

    Gorban, Alexander N.

    Hydrodynamic and Structural Performance of the Transverse Horizontal Axis Water Turbine Prof. Guy across the flow THAWT Concept Transverse Horizontal Axis Water Turbine · Length limited only by stiffness;Options for tidal stream power (1) · Axial flow turbines ("underwater windmills") ­ "Unducted" » MCT (most

  4. One dimensional electromagnetic relativistic PIC-hydrodynamic hybrid simulation code H-VLPL

    E-Print Network [OSTI]

    Grimm, Volker

    One dimensional electromagnetic relativistic PIC-hydrodynamic hybrid simulation code H-VLPL (Hybrid full electromagnetic relativistic hybrid plasma model. The full kinetic particle-in cell (PIC, there is a demand to simulate high density plasmas, e.g., in the experiments where the laser pulse interacts

  5. Experiments on wind-perturbed rogue wave hydrodynamics using the Peregrine breather model

    E-Print Network [OSTI]

    Boyer, Edmond

    Engineering, Imperial College London, London SW7 2AZ, United Kingdom 2 Dynamics Group, Hamburg University on the surface that results in a flux of energy from the wind to the waves and (ii) it generates a rotationalExperiments on wind-perturbed rogue wave hydrodynamics using the Peregrine breather model A

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

    E-Print Network [OSTI]

    Suslick, Kenneth S.

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

  7. Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines

    E-Print Network [OSTI]

    Pedersen, Tom

    Turbines by Michael Robert Shives B.Eng., Carleton University, 2008 A Dissertation Submitted in Partial Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines) #12;iii ABSTRACT This thesis examines methods for designing and analyzing kinetic turbines based

  8. Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines

    E-Print Network [OSTI]

    Victoria, University of

    Turbines by Michael Robert Shives B.Eng., Carleton University, 2008 A Thesis Submitted in Partial Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines examines methods for designing and analyzing kinetic turbines based on blade element momentum (BEM) theory

  9. A limpet shell shape that reduces drag: laboratory demonstration of a hydrodynamic mechanism and an exploration of its effectiveness in nature

    E-Print Network [OSTI]

    Denny, Mark

    A limpet shell shape that reduces drag: laboratory demonstration of a hydrodynamic mechanism shell shape that reduces drag: laboratory demonstration of a hydrodynamic mechanism and an exploration that reduces drag: laboratory demonstration of a hydrodynamic mechanism and an exploration of its effectiveness

  10. Test quality

    SciTech Connect (OSTI)

    Hartley, R.S. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Keller, A.E. [Nuclear Regulatory Commission, Washington, DC (United States)

    1992-09-01T23:59:59.000Z

    This document discusses inservice testing of safety-related components at nuclear power plants which is performed under the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (the Code). Subsections IWP and IWV of Section XI of the Code state test method and frequency requirements for pumps and valves respectively. Tests vary greatly in quality and frequency. This paper explores the concept of test quality and its relationship with operational readiness and preventive maintenance. This paper also considers the frequencies of component testing. Test quality is related to a test`s ability to detect degradation that can cause component failure. The quality of the test depends on several factors, including specific parameters measured, system or component conditions, and instrument accuracy. The quality of some currently required tests for check valves, motor-operated valves, and pumps is also discussed. Suggestions are made to improve test quality by measuring different parameters, testing valves under load, and testing positive displacement pumps at high pressure and centrifugal pumps at high flow rate conditions. These suggestions can help to improve the level of assurance of component operational readiness gained from testing.

  11. A pulsed power hydrodynamics approach to exploring properties of warm dense matter

    SciTech Connect (OSTI)

    Reinovsky, Robert Emil [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    Pulsed Power Hydrodynamics, as an application of low-impedance, pulsed power, and high magnetic field technology developed over the last decade to study advanced hydrodynamic problems, instabilities, turbulence, and material properties, can potentially be applied to the study of the behavior and properties of warm dense matter (WDM) as well. Exploration of the properties, such as equation of state and conductivity, of warm dense matter is an emerging area of study focused on the behavior of matter at density near solid density (from 10% of solid density to a few times solid density) and modest temperatures ({approx}1-10 eV). Warm dense matter conditions can be achieved by laser or particle beam heating of very small quantities of matter on timescales short compared to the subsequent hydrodynamic expansion timescales (isochoric heating) and a vigorous community of researchers is applying these techniques using petawatt scale laser systems, but the microscopic size scale of the WDM produced in this way limits access to some physics phenomena. Pulsed power hydrodynamics techniques, either through high convergence liner compression of a large volume, modest density, low temperature plasma to densities approaching solid density or through the explosion and subsequent expansion of a conductor (wire) against a high pressure (density) gas background (isobaric expansion) techniques both offer the prospect for producing warm dense matter in macroscopic quantities. However, both techniques demand substantial energy, proper power conditioning and delivery, and an understanding of the hydrodynamic and instability processes that limit each technique. Similarly, liner compression of normal density material, perhaps using multiple reflected shocks can provide access to the challenging region above normal density -- again with the requirement of very large amounts of driving energy. In this paper we will provide an introduction to techniques that might be applied to explore this interesting new application of the energy-rich technology of pulse power and high magnetic fields.

  12. Test quality

    SciTech Connect (OSTI)

    Hartley, R.S. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Keller, A.E. (Nuclear Regulatory Commission, Washington, DC (United States))

    1992-01-01T23:59:59.000Z

    This document discusses inservice testing of safety-related components at nuclear power plants which is performed under the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (the Code). Subsections IWP and IWV of Section XI of the Code state test method and frequency requirements for pumps and valves respectively. Tests vary greatly in quality and frequency. This paper explores the concept of test quality and its relationship with operational readiness and preventive maintenance. This paper also considers the frequencies of component testing. Test quality is related to a test's ability to detect degradation that can cause component failure. The quality of the test depends on several factors, including specific parameters measured, system or component conditions, and instrument accuracy. The quality of some currently required tests for check valves, motor-operated valves, and pumps is also discussed. Suggestions are made to improve test quality by measuring different parameters, testing valves under load, and testing positive displacement pumps at high pressure and centrifugal pumps at high flow rate conditions. These suggestions can help to improve the level of assurance of component operational readiness gained from testing.

  13. Test Images

    E-Print Network [OSTI]

    Test Images. I hope to have a set of test images for the course soon. Some images are available now; some will have to wait until I can find another 100-200

  14. CTH simulation of PBX-9501 Taylor tests /

    SciTech Connect (OSTI)

    Koby, Joseph R.

    2011-09-01T23:59:59.000Z

    During March-May 2011, multiple Taylor impact tests were conducted at LANL, examining the behavior of PBXN-9 and PBX-9501 under rapid loading. Subsequently, a computational hydrodynamics code (CTH) model was developed to mimic the deformation behavior observed in these impact tests with PBX-9501 would likely initiate upon impact. Also examined was whether an inert slud behind the explosive would lead to initiation at lower, more easily attainable velocities. The simplified model used here showed a minimum velocity for ignition of 530 m/s which was unchanged by the addition of a plastic slud behind the sample. The use of a lead slug did lower the minimum velocity to 460 m/s. These values are likely more qualitative at this point because multiple simplifications are currently used in the materials properties and test geometry. The results do show that this approach is capable of determining ignition due to Taylor impact.

  15. Fluctuating hydrodynamics of multispecies mixtures. I. Non-reacting Flows

    E-Print Network [OSTI]

    Balakrishnan, Kaushik; Donev, Aleksandar; Bell, John B

    2013-01-01T23:59:59.000Z

    In this paper we discuss the formulation of the fluctuating Navier-Stokes (FNS) equations for multi-species, non-reactive fluids. In particular, we establish a form suitable for numerical solution of the resulting stochastic partial differential equations. An accurate and efficient numerical scheme, based on our previous methods for single species and binary mixtures, is presented and tested at equilibrium as well as for a variety of non-equilibrium problems. These include the study of giant nonequilibrium concentration fluctuations in a ternary mixture in the presence of a diffusion barrier, the triggering of a Rayleigh-Taylor instability by diffusion in a four-species mixture, as well as reverse diffusion in a ternary mixture. Good agreement with theory and experiment demonstrates that the formulation is robust and can serve as a useful tool in the study of thermal fluctuations for multi- species fluids. The extension to include chemical reactions will be treated in a sequel paper.

  16. REVIEW OF EXPERIMENTAL CAPABILITIES AND HYDRODYNAMIC DATA FOR VALIDATION OF CFD-BASED PREDICTIONS FOR SLURRY BUBBLE COLUMN REACTORS

    SciTech Connect (OSTI)

    Donna Post Guillen; Daniel S. Wendt; Steven P. Antal; Michael Z. Podowski

    2007-11-01T23:59:59.000Z

    The purpose of this paper is to document the review of several open-literature sources of both experimental capabilities and published hydrodynamic data to aid in the validation of a Computational Fluid Dynamics (CFD) based model of a slurry bubble column (SBC). The review included searching the Web of Science, ISI Proceedings, and Inspec databases, internet searches as well as other open literature sources. The goal of this study was to identify available experimental facilities and relevant data. Integral (i.e., pertaining to the SBC system), as well as fundamental (i.e., separate effects are considered), data are included in the scope of this effort. The fundamental data is needed to validate the individual mechanistic models or closure laws used in a Computational Multiphase Fluid Dynamics (CMFD) simulation of a SBC. The fundamental data is generally focused on simple geometries (i.e., flow between parallel plates or cylindrical pipes) or custom-designed tests to focus on selected interfacial phenomena. Integral data covers the operation of a SBC as a system with coupled effects. This work highlights selected experimental capabilities and data for the purpose of SBC model validation, and is not meant to be an exhaustive summary.

  17. REVIEW OF EXPERIMENTAL CAPABILITIES AND HYDRODYNAMIC DATA FOR VALIDATION OF CFD BASED PREDICTIONS FOR SLURRY BUBBLE COLUMN REACTORS

    SciTech Connect (OSTI)

    Donna Post Guillen; Daniel S. Wendt

    2007-11-01T23:59:59.000Z

    The purpose of this paper is to document the review of several open-literature sources of both experimental capabilities and published hydrodynamic data to aid in the validation of a Computational Fluid Dynamics (CFD) based model of a slurry bubble column (SBC). The review included searching the Web of Science, ISI Proceedings, and Inspec databases, internet searches as well as other open literature sources. The goal of this study was to identify available experimental facilities and relevant data. Integral (i.e., pertaining to the SBC system), as well as fundamental (i.e., separate effects are considered), data are included in the scope of this effort. The fundamental data is needed to validate the individual mechanistic models or closure laws used in a Computational Multiphase Fluid Dynamics (CMFD) simulation of a SBC. The fundamental data is generally focused on simple geometries (i.e., flow between parallel plates or cylindrical pipes) or custom-designed tests to focus on selected interfacial phenomena. Integral data covers the operation of a SBC as a system with coupled effects. This work highlights selected experimental capabilities and data for the purpose of SBC model validation, and is not meant to be an exhaustive summary.

  18. Development of a sub-scale dynamics model for pressure relaxation of multi-material cells in Lagrangian hydrodynamics

    SciTech Connect (OSTI)

    Harrison, Alan K [Los Alamos National Laboratory; Shashkov, Mikhail J [Los Alamos National Laboratory; Fung, Jimmy [Los Alamos National Laboratory; Canfield, Thomas R [Los Alamos National Laboratory; Kamm, James R [SNLA

    2010-10-14T23:59:59.000Z

    We have extended the Sub-Scale Dynamics (SSD) closure model for multi-fluid computational cells. Volume exchange between two materials is based on the interface area and a notional interface translation velocity, which is derived from a linearized Riemann solution. We have extended the model to cells with any number of materials, computing pressure-difference-driven volume and energy exchange as the algebraic sum of pairwise interactions. In multiple dimensions, we rely on interface reconstruction to provide interface areas and orientations, and centroids of material polygons. In order to prevent unphysically large or unmanageably small material volumes, we have used a flux-corrected transport (FCT) approach to limit the pressure-driven part of the volume exchange. We describe the implementation of this model in two dimensions in the FLAG hydrodynamics code. We also report on Lagrangian test calculations, comparing them with others made using a mixed-zone closure model due to Tipton, and with corresponding calculations made with only single-material cells. We find that in some cases, the SSD model more accurately predicts the state of material in mixed cells. By comparing the algebraic forms of both models, we identify similar dependencies on state and dynamical variables, and propose explanations for the apparent higher fidelity of the SSD model.

  19. Jet Induced Supernovae-Hydrodynamics and Observational Consequences

    E-Print Network [OSTI]

    A. Khokhlov; Peter Hoeflich

    2000-11-01T23:59:59.000Z

    Core collapse supernovae (SN) are the final stages of stellar evolution in massive stars during which the central region collapses, forms a neutron star (NS), and the outer layers are ejected. Recent explosion scenarios assumed that the ejection is due to energy deposition by neutrinos into the envelope but detailed models do not produce powerful explosions. There is mounting evidence for an asphericity in the SN which is difficult to explain within this picture. This evidence includes the observed high polarization, pulsar kicks, high velocity iron-group and intermediate-mass elements material observed in remnants, etc. The discovery of highly magnetars revived the idea that the basic mechanism for the ejection of the envelope is related to a highly focused MHD-jet formed at the NS. Our 3-D hydro simulations of the jet propagation through the star confirmed that the mechanism can explain the asphericities. In this paper, detailed 3-D models for jet induced explosions of "classical" core collapse supernovae are presented. We demonstrate the influence of the jet properties and of the underlaying progenitor structure on the final density and chemical structure. Finally, we discuss the observational consequences, predictions and tests of this scenario.

  20. Kinetic freeze-out, particle spectra and harmonic flow coefficients from mode-by-mode hydrodynamics

    E-Print Network [OSTI]

    Stefan Floerchinger; Urs Achim Wiedemann

    2014-08-27T23:59:59.000Z

    The kinetic freeze-out for the hydrodynamical description of relativistic heavy ion collisions is discussed using a background-fluctuation splitting of the hydrodynamical fields. For a single event, the particle spectrum, or its logarithm, can be written as the sum of background part that is symmetric with respect to azimuthal rotations and longitudinal boosts and a part containing the contribution of fluctuations or deviations from the background. Using a complete orthonormal basis to characterize the initial state allows one to write the double differential harmonic flow coefficients determined by the two-particle correlation method as matrix expressions involving the initial fluid correlations. We discuss the use of these expressions for a mode-by-mode analysis of fluctuating initial conditions in heavy ion collisions.

  1. Super stellar clusters with a bimodal hydrodynamic solution: an Approximate Analytic Approach

    E-Print Network [OSTI]

    Wünsch, R; Palous, J; Tenorio-Tagle, G

    2007-01-01T23:59:59.000Z

    We look for a simple analytic model to distinguish between stellar clusters undergoing a bimodal hydrodynamic solution from those able to drive only a stationary wind. Clusters in the bimodal regime undergo strong radiative cooling within their densest inner regions, which results in the accumulation of the matter injected by supernovae and stellar winds and eventually in the formation of further stellar generations, while their outer regions sustain a stationary wind. The analytic formulae are derived from the basic hydrodynamic equations. Our main assumption, that the density at the star cluster surface scales almost linearly with that at the stagnation radius, is based on results from semi-analytic and full numerical calculations. The analytic formulation allows for the determination of the threshold mechanical luminosity that separates clusters evolving in either of the two solutions. It is possible to fix the stagnation radius by simple analytic expressions and thus to determine the fractions of the depo...

  2. Hydrodynamic flow in the vicinity of a nanopore induced by an applied voltage

    E-Print Network [OSTI]

    Mao, Mao; Hu, Guohui

    2013-01-01T23:59:59.000Z

    Continuum simulation is employed to study ion transport and fluid flow through a nanopore in a solid-state membrane under an applied potential drop. Results show the existence of concentration polarization layers on the surfaces of the membrane. The nonuniformity of the ionic distribution gives rise to an electric pressure that drives vortical motion in the fluid. There is also a net hydrodynamic flow through the nanopore due to an asymmetry induced by the membrane surface charge. The qualitative behavior is similar to that observed in a previous study using molecular dynamic simulations. The current--voltage characteristics show some nonlinear features but are not greatly affected by the hydrodynamic flow in the parameter regime studied. In the limit of thin Debye layers, the electric resistance of the system can be characterized using an equivalent circuit with lumped parameters. Generation of vorticity can be understood qualitatively from elementary considerations of the Maxwell stresses. However, the flow...

  3. Low torque hydrodynamic lip geometry for bi-directional rotation seals

    DOE Patents [OSTI]

    Dietle, Lannie L. (Houston, TX); Schroeder, John E. (Richmond, TX)

    2011-11-15T23:59:59.000Z

    A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

  4. Low torque hydrodynamic lip geometry for bi-directional rotation seals

    DOE Patents [OSTI]

    Dietle, Lannie L. (Houston, TX); Schroeder, John E. (Richmond, TX)

    2009-07-21T23:59:59.000Z

    A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

  5. Hydrodynamic models of self-organized dynamics: derivation and existence theory

    E-Print Network [OSTI]

    Pierre Degond; Jian-Guo Liu; Sébastien Motsch; Vladislav Panferov

    2011-08-16T23:59:59.000Z

    This paper is concerned with the derivation and analysis of hydrodynamic models for systems of self-propelled particles subject to alignment interaction and attraction-repulsion. The starting point is the kinetic model considered in earlier work of Degond & Motsch with the addition of an attraction-repulsion interaction potential. Introducing different scalings than in Degond & Motsch, the non-local effects of the alignment and attraction-repulsion interactions can be kept in the hydrodynamic limit and result in extra pressure, viscosity terms and capillary force. The systems are shown to be symmetrizable hyperbolic systems with viscosity terms. A local-in-time existence result is proved in the 2D case for the viscous model and in the 3D case for the inviscid model. The proof relies on the energy method.

  6. Liquid contact resonance atomic force microscopy via experimental reconstruction of the hydrodynamic function

    SciTech Connect (OSTI)

    Tung, Ryan C., E-mail: ryan.tung@nist.gov; Killgore, Jason P.; Hurley, Donna C. [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States)

    2014-06-14T23:59:59.000Z

    We present a method to correct for surface-coupled inertial and viscous fluid loading forces in contact resonance (CR) atomic force microscopy (AFM) experiments performed in liquid. Based on analytical hydrodynamic theory, the method relies on experimental measurements of the AFM cantilever's free resonance peaks near the sample surface. The free resonance frequencies and quality factors in both air and liquid allow reconstruction of a continuous hydrodynamic function that can be used to adjust the CR data in liquid. Validation experiments utilizing thermally excited free and in-contact spectra were performed to assess the accuracy of our approach. Results show that the method recovers the air frequency values within approximately 6%. Knowledge of fluid loading forces allows current CR analysis techniques formulated for use in air and vacuum environments to be applied to liquid environments. Our technique greatly extends the range of measurement environments available to CR-AFM.

  7. Non-Abelian hydrodynamics and the flow of spin in spin-orbit coupled substances

    SciTech Connect (OSTI)

    Leurs, B.W.A. [Instituut Lorentz for Theoretical Physics, Leiden University, Leiden (Netherlands)], E-mail: leurs@lorentz.leidenuniv.nl; Nazario, Z.; Santiago, D.I.; Zaanen, J. [Instituut Lorentz for Theoretical Physics, Leiden University, Leiden (Netherlands)

    2008-04-15T23:59:59.000Z

    Motivated by the heavy ion collision experiments there is much activity in studying the hydrodynamical properties of non-Abelian (quark-gluon) plasmas. A major question is how to deal with color currents. Although not widely appreciated, quite similar issues arise in condensed matter physics in the context of the transport of spins in the presence of spin-orbit coupling. The key insight is that the Pauli Hamiltonian governing the leading relativistic corrections in condensed matter systems can be rewritten in a language of SU(2) covariant derivatives where the role of the non-Abelian gauge fields is taken by the physical electromagnetic fields: the Pauli system can be viewed as Yang-Mills quantum-mechanics in a 'fixed frame', and it can be viewed as an 'analogous system' for non-Abelian transport in the same spirit as Volovik's identification of the He superfluids as analogies for quantum fields in curved space time. We take a similar perspective as Jackiw and coworkers in their recent study of non-Abelian hydrodynamics, twisting the interpretation into the 'fixed frame' context, to find out what this means for spin transport in condensed matter systems. We present an extension of Jackiw's scheme: non-Abelian hydrodynamical currents can be factored in a 'non-coherent' classical part, and a coherent part requiring macroscopic non-Abelian quantum entanglement. Hereby it becomes particularly manifest that non-Abelian fluid flow is a much richer affair than familiar hydrodynamics, and this permits us to classify the various spin transport phenomena in condensed matter physics in an unifying framework. The 'particle based hydrodynamics' of Jackiw et al. is recognized as the high temperature spin transport associated with semiconductor spintronics. In this context the absence of faithful hydrodynamics is well known, but in our formulation it is directly associated with the fact that the covariant conservation of non-Abelian currents turns into a disastrous non-conservation of the incoherent spin currents of the high temperature limit. We analyze the quantum-mechanical single particle currents of relevance to mesoscopic transport with as highlight the Ahronov-Casher effect, where we demonstrate that the intricacies of the non-Abelian transport render this effect to be much more fragile than its abelian analog, the Ahronov-Bohm effect. We subsequently focus on spin flows protected by order parameters. At present there is much interest in multiferroics where non-collinear magnetic order triggers macroscopic electric polarization via the spin-orbit coupling. We identify this to be a peculiarity of coherent non-Abelian hydrodynamics: although there is no net particle transport, the spin entanglement is transported in these magnets and the coherent spin 'super' current in turn translates into electric fields with the bonus that due to the requirement of single valuedness of the magnetic order parameter a true hydrodynamics is restored. Finally, 'fixed-frame' coherent non-Abelian transport comes to its full glory in spin-orbit coupled 'spin superfluids', and we demonstrate a new effect: the trapping of electrical line charge being a fixed frame, non-Abelian analog of the familiar magnetic flux trapping by normal superconductors. The only known physical examples of such spin superfluids are the {sup 3}He A- and B-phase where unfortunately the spin-orbit coupling is so weak that it appears impossible to observe these effects.

  8. Running faster together: huge speed up of thermal ratchets due to hydrodynamic coupling

    E-Print Network [OSTI]

    Paolo Malgaretti; Ignacio Pagonabarraga; Daan Frenkel

    2012-09-19T23:59:59.000Z

    We present simulations that reveal a surprisingly large effect of hydrodynamic coupling on the speed of thermal ratchet motors. The model that we use considers particles performing thermal ratchet motion in a hydrodynamic solvent. Using particle-based, mesoscopic simulations that maintain local momentum conservation, we analyze quantitatively how the coupling to the surrounding fluid affects ratchet motion. We find that coupling can increase the mean velocity of the moving particles by almost two orders of magnitude, precisely because ratchet motion has both a diffusive and a deterministic component. The resulting coupling also leads to the formation of aggregates at longer times. The correlated motion that we describe increases the efficiency of motor-delivered cargo transport and we speculate that the mechanism that we have uncovered may play a key role in speeding up molecular motor-driven intracellular transport.

  9. Astrophysical hydrodynamics with a high-order discontinuous Galerkin scheme and adaptive mesh refinement

    E-Print Network [OSTI]

    Schaal, Kevin; Chandrashekar, Praveen; Pakmor, Rüdiger; Klingenberg, Christian; Springel, Volker

    2015-01-01T23:59:59.000Z

    Solving the Euler equations of ideal hydrodynamics as accurately and efficiently as possible is a key requirement in many astrophysical simulations. It is therefore important to continuously advance the numerical methods implemented in current astrophysical codes, especially also in light of evolving computer technology, which favours certain computational approaches over others. Here we introduce the new adaptive mesh refinement (AMR) code TENET, which employs a high-order Discontinuous Galerkin (DG) scheme for hydrodynamics. The Euler equations in this method are solved in a weak formulation with a polynomial basis by means of explicit Runge-Kutta time integration and Gauss-Legendre quadrature. This approach offers significant advantages over commonly employed finite volume (FV) solvers. In particular, the higher order capability renders it computationally more efficient, in the sense that the same precision can be obtained at significantly less computational cost. Also, the DG scheme inherently conserves a...

  10. Laboratory Experiments and Hydrodynamic Modeling of a Bed Leveler Used to Level the Bottom of Ship Channels after Dredging

    E-Print Network [OSTI]

    Paul, Ephraim Udo

    2011-02-22T23:59:59.000Z

    This study was conducted to ascertain the impacts of bed leveling, following ship channel dredging operations, and to also investigate the hydrodynamic flow field around box bed levelers. Laboratory experiments were conducted with bed levelers...

  11. Hydrodynamic and transport phenomena at the interface between flow and aquatic vegetation : from the forest to the blade scale

    E-Print Network [OSTI]

    Rominger, Jeffrey T. (Jeffrey Tsaros)

    2014-01-01T23:59:59.000Z

    From the canopy scale to the blade scale, interactions between fluid motion and kelp produce a wide array of hydrodynamic and scalar transport phenomena. At the kilometer scale of the kelp forest, coastal currents transport ...

  12. Hydrodynamic models for slurry bubble column reactors. Seventh technical progress report, January--March 1996

    SciTech Connect (OSTI)

    Gidaspow, D.

    1996-04-01T23:59:59.000Z

    The objective of this investigation is to convert our ``learning gas solid-liquid`` fluidization model into a predictive design model. The IIT hydrodynamic model computes the phase velocities and the volume fractions of gas, liquid and particulate phase. Model verification involves a comparison of these computed velocities and volume fractions to experimental values. A hydrodynamic model for multiphase flows, based on the principles of mass, momentum and energy conservation for each phase, was developed and applied to model gas-liquid, gas-liquid-solid fluidization and gas-solid-solid separation. To simulate the industrial slurry bubble column reactors, a computer program based on the hydrodynamic model was written with modules for chemical reactions (e.g. the synthesis of methanol), phase changes and heat exchangers. In the simulations of gas-liquid two phases flow system, the gas hold-ups, computed with a variety of operating conditions such as temperature, pressure, gas and liquid velocities, agree well with the measurements obtained at Air Products` pilot plant. The hydrodynamic model has more flexible features than the previous empirical correlations in predicting the gas hold-up of gas-liquid two-phase flow systems. In the simulations of gas-liquid-solid bubble column reactors with and without slurry circulation, the code computes volume fractions, temperatures and velocity distributions for the gas, the liquid and the solid phases, as well as concentration distributions for the species (CO, H{sub 2}, CH{sub 3}0H, ... ), after startup from a certain initial state. A kinetic theory approach is used to compute a solid viscosity due to particle collisions. Solid motion and gas-liquid-solid mixing are observed on a color PCSHOW movie made from computed time series data. The steady state and time average catalyst concentration profiles, the slurry height and the rates of methanol production agree well with the measurements obtained at an Air Products` pilot plant.

  13. Hydrodynamic simulations of a combined hydrogen, helium thermonuclear runaway on a 10-km neutron star

    SciTech Connect (OSTI)

    Starrfield, S.; Kenyon, S.; Truran, J.W.; Sparks, W.M.

    1983-01-01T23:59:59.000Z

    We have used a Lagrangian, hydrodynamic stellar-evolution computer code to evolve a thermonuclear runaway in the accreted hydrogen rich envelope of a 1.0M, 10-km neutron star. Our simulation produced an outburst which lasted about 2000 sec and peak effective temperature was 3 keV. The peak luminosity exceeded 2 x 10/sup 5/ L. A shock wave caused a precursor in the light curve which lasted 10/sup -5/ sec.

  14. Simulation study of the effect of hydrodynamic forces on oil recovery

    E-Print Network [OSTI]

    Idrobo Hurtado, Eduardo Alejandro

    1992-01-01T23:59:59.000Z

    the potential at the intersections of the oil-water contacts of a specific grid pattern in Mishrif Fields, offshore Iran. They determined the inclinations of the oil-water contacts from the changes of potential. Tsenng in 1983 used a computer simulator... to study hydrodynamic flow in the Lower Cretaceous Muddy Sandstone, Bell Creek Field, Montana. The potentiometric surfaces were found to be influenced not only by the permeability variations but also by vertical permeability. However, in this case...

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

    E-Print Network [OSTI]

    Lin, Joseph Tien-Chin

    1978-01-01T23:59:59.000Z

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

  16. Development and evaluation of a coupled hydrodynamic (FVCOM) and water quality model (CE-QUAL-ICM)

    SciTech Connect (OSTI)

    Kim, Taeyun; Labiosa, Rochelle G.; Khangaonkar, Tarang; Yang, Zhaoqing; Chen, Changsheng; Qi, Jianhua; Cerco, Carl

    2010-01-08T23:59:59.000Z

    Recent and frequent fish-kills in waters otherwise known for their pristine high quality, created increased awareness and urgent concern regarding potential for degradation of water quality in Puget Sound through coastal eutrophication caused by increased nutrient loading. Following a detailed review of leading models and tools available in public domain, FVCOM and CE-QUAL-ICM models were selected to conduct hydrodynamic and water quality simulations for the fjordal waters of Puget Sound.

  17. Neutrino transport and hydrodynamic stability of rotating proto-neutron stars

    E-Print Network [OSTI]

    V. Urpin

    2007-04-24T23:59:59.000Z

    We consider stability of differentially rotating non-magnetic proto-neutron stars. When neutrino transport is efficient, the star can be subject to a diffusive instability that can occur even in the convectively stable region. The instability arises on the time-scale comparable to the time-scale of thermal diffusion. Hydrodynamic motions driven by the instability can lead to anisotropy in the neutrino flux since the instability is suppressed near the equator and rotation axis.

  18. General relativistic radiation hydrodynamics of accretion flows. I: Bondi-Hoyle accretion

    E-Print Network [OSTI]

    Olindo Zanotti; Constanze Roedig; Luciano Rezzolla; Luca Del Zanna

    2015-03-10T23:59:59.000Z

    We present a new code for performing general-relativistic radiation-hydrodynamics simulations of accretion flows onto black holes. The radiation field is treated in the optically-thick approximation, with the opacity contributed by Thomson scattering and thermal bremsstrahlung. Our analysis is concentrated on a detailed numerical investigation of hot two-dimensional, Bondi-Hoyle accretion flows with various Mach numbers. We find significant differences with respect to purely hydrodynamical evolutions. In particular, once the system relaxes to a radiation-pressure dominated regime, the accretion rates become about two orders of magnitude smaller than in the purely hydrodynamical case, remaining however super-Eddington as are the luminosities. Furthermore, when increasing the Mach number of the inflowing gas, the accretion rates become smaller because of the smaller cross section of the black hole, but the luminosities increase as a result a stronger emission in the shocked regions. Overall, our approach provides the first self-consistent calculation of the Bondi-Hoyle luminosity, most of which is emitted within r~100 M from the black hole, with typical values L/L_Edd ~ 1-7, and corresponding energy efficiencies eta_BH ~ 0.09-0.5. The possibility of computing luminosities self-consistently has also allowed us to compare with the bremsstrahlung luminosity often used in modelling the electromagnetic counterparts to supermassive black-hole binaries, to find that in the optically-thick regime these more crude estimates are about 20 times larger than our radiation-hydrodynamics results.

  19. Hydrodynamic effect on oil accumulation in a stratigraphic trap, Kitty Field, Powder River Basin, Wyoming

    E-Print Network [OSTI]

    Larberg, Gregory Martin

    1976-01-01T23:59:59.000Z

    stratigraphic traps in the Lower Cretaceous Muddy Sandstones on the east flank of the basin (Figure 1). The nine ? township area immediately surrounding Kitty in- cludes Kingsbury and Mill ? Gillette fields and is well ? suited for hydrodynamic study because... understanding of the relationships between pressures, flow, and the rocks themselves. 14 Nethods Subsurface data from the nine township area surround- ing Kitty field is abundant and readily available from in- dustry sources. Over 530 class "A" (analyzable...

  20. Granular Solid Hydrodynamics (GSH): a broad-ranged macroscopic theory of granular media

    E-Print Network [OSTI]

    Yimin Jiang; Mario Liu

    2014-07-27T23:59:59.000Z

    A unified continuum-mechanical theory has been until now lacking for granular media, some believe it could not exist. Derived employing the hydrodynamic approach, GSH is such a theory, though as yet a qualitative one. The behavior being accounted for includes static stress distribution, elastic wave, elasto-plastic motion, the critical state and rapid dense flow. The equations and application to a few typical experiments are presented here.

  1. Hydrodynamic Crossovers in Surface-Directed Spinodal Decomposition and Surface Enrichment

    E-Print Network [OSTI]

    Prabhat K. Jaiswal; Sanjay Puri; Subir K. Das

    2010-11-29T23:59:59.000Z

    We present comprehensive molecular dynamics (MD) results for the kinetics of surface-directed spinodal decomposition (SDSD) and surface enrichment (SE) in binary mixtures at wetting surfaces. We study the surface morphology and the growth dynamics of the wetting and enrichment layers. The growth law for the thickness of these layers shows a crossover from a diffusive regime to a hydrodynamic regime. We provide phenomenological arguments to understand this crossover.

  2. Hydrodynamic heave damping estimation and scaling for tension leg platforms

    SciTech Connect (OSTI)

    Thiagarajan, K.P.; Troesch, A.W. (Univ. of Michigan, Ann Arbor, MI (United States))

    1994-05-01T23:59:59.000Z

    Resonant heave excitation of tension leg platform (TLP) tendons is typically of high-frequency and small amplitude. The response of the tendons to this excitation is non-negligible due to a very small drag coefficient of the structure in this mode of oscillation. Small values of the drag force complicate experimental estimation in a laboratory due to the dominating inertial force. Model tests conducted at the University of Michigan investigating the damping experienced by a cylinder of 0.457 m (1.5 ft) diameter and 1.219 m (4.0 ft) draft are described here. The cylinder is vertical and surface-piercing, and oscillates parallel to its axis. The amplitude of the forcing is varied to give a Keulegan-Carpenter (KC) number range of 0.1--1.0. The frequency parameter [beta] is 89236, corresponding to an oscillation frequency of 0.41 Hz. From these experiments, a definite nonlinear trend is observed between the drag force and velocity conflicting with some of the results reported by Huse (1990) and Chakrabarti and Hanna (1991). The heave damping coefficients of individual structural components of a TLP follow different scaling laws. Rules are presented for scaling friction and form drag components from model to full scale. Results from experiments are used to obtain a scaling law for vertical columns of a TLP. Previously published results are used for horizontal pontoons. An example TLP calculation shows that the heave damping ratio of horizontal cylinders is approximately 0.049--0.078 percent, depending upon cylinder shape, and that for vertical cylinders is in the range 0.025--0.171 percent, depending upon KC.

  3. A new scheme of causal viscous hydrodynamics for relativistic heavy-ion collisions: A Riemann solver for quark–gluon plasma

    SciTech Connect (OSTI)

    Akamatsu, Yukinao, E-mail: akamatsu@kmi.nagoya-u.ac.jp [Kobayashi–Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University, Nagoya 464-8602 (Japan)] [Kobayashi–Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University, Nagoya 464-8602 (Japan); Inutsuka, Shu-ichiro [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan)] [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan); Nonaka, Chiho [Kobayashi–Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University, Nagoya 464-8602 (Japan) [Kobayashi–Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University, Nagoya 464-8602 (Japan); Department of Physics, Nagoya University, Nagoya 464-8602 (Japan); Takamoto, Makoto [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan) [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan); Max-Planck-Institut für Kernphysik, Postfach 103980, 69029 Heidelberg (Germany)

    2014-01-01T23:59:59.000Z

    In this article, we present a state-of-the-art algorithm for solving the relativistic viscous hydrodynamics equation with the QCD equation of state. The numerical method is based on the second-order Godunov method and has less numerical dissipation, which is crucial in describing of quark–gluon plasma in high-energy heavy-ion collisions. We apply the algorithm to several numerical test problems such as sound wave propagation, shock tube and blast wave problems. In sound wave propagation, the intrinsic numerical viscosity is measured and its explicit expression is shown, which is the second-order of spatial resolution both in the presence and absence of physical viscosity. The expression of the numerical viscosity can be used to determine the maximum cell size in order to accurately measure the effect of physical viscosity in the numerical simulation.

  4. Radiographic and Histopathologic Observations After Combined EGFR Inhibition and Hypofractionated Stereotactic Radiosurgery in Patients With Recurrent Malignant Gliomas

    SciTech Connect (OSTI)

    Schwer, Amanda L.; Kavanagh, Brian D.; McCammon, Robert; Gaspar, Laurie E. [Department of Radiation Oncology, University of Colorado Denver, Aurora, CO (United States); Kleinschmidt-De Masters, B.K. [Department of Pathology, University of Colorado Denver, Aurora, CO (United States); Stuhr, Kelly [Department of Radiation Oncology, University of Colorado Denver, Aurora, CO (United States); Chen Changhu [Department of Radiation Oncology, University of Colorado Denver, Aurora, CO (United States)], E-mail: Changhu.Chen@UCDenver.edu

    2009-04-01T23:59:59.000Z

    Purpose: To describe the radiographic and histopathologic changes after stereotactic radiosurgery (SRS) and epidermal growth factor receptor inhibition in patients with recurrent malignant gliomas. Methods and Materials: A total of 15 patients with recurrent high-grade gliomas were treated on a prospective Phase I trial combining SRS and gefitinib. The SRS dose was escalated from 18 to 36 Gy in three fractions. The planning target volume was the T{sub 1}-weighted contrast-enhancing (T{sub 1}C) lesion plus 2 mm. Gefitinib was given at 250 mg daily. Serial brain magnetic resonance imaging scans were analyzed to characterize the volumetric changes in the T{sub 1}C and T{sub 2} abnormalities after treatment. Two patients underwent resection for suspected recurrence. Results: The median pretreatment magnetic resonance imaging T{sub 1}C and T{sub 2} volume was 40.9 and 184.1 cm{sup 3}, respectively. The median post-SRS percentage of increases in the T{sub 1}C volume at 1, 2-4, and 5-7 months was 8.9%, 41.3%, and 99.6%, respectively. The median percentage increase in the T{sub 2} volume likewise showed a trend upward after SRS, from 18.0% at 1 month to 37.8% at 5-7 months. For the 2 patients who underwent resection after SRS for an increasing T{sub 1}C volume, the histopathologic analysis revealed therapy-induced vascular injury and necrosis. One patient with an asymptomatic increase in the T{sub 1}C volume after SRS was treated conservatively. After a peak T{sub 1}C volume increase at 9 months, the T{sub 1}C volume had declined to 50% of the maximal volume at 15 months. The patients with the most dramatic increase in T{sub 1}C volume experienced the longest overall survival. Conclusion: Patients experienced a notable increase in magnetic resonance imaging T{sub 1}C and T{sub 2} volumes after the combination of SRS and epidermal growth factor receptor inhibition. The tissue changes were consistent with a potent treatment effect.

  5. Causal hydrodynamics from kinetic theory by doublet scheme in renormalization-group method

    E-Print Network [OSTI]

    Kyosuke Tsumura; Teiji Kunihiro

    2014-09-10T23:59:59.000Z

    We develop a general framework in the renormalization-group (RG) method for extracting a mesoscopic dynamics from an evolution equation by incorporating some excited (fast) modes as additional components to the invariant manifold spanned by zero modes. We call this framework the doublet scheme. We apply the doublet scheme to construct causal hydrodynamics as a mesoscopic dynamics of kinetic theory, i.e., the Boltzmann equation, in a systematic manner with no ad-hoc assumption. It is found that our equation has the same form as Grad's thirteen-moment causal hydrodynamic equation, but the microscopic formulae of the transport coefficients and relaxation times are different. In fact, in contrast to the Grad equation, our equation leads to the same expressions for the transport coefficients as given by the Chapman-Enskog expansion method and suggests novel formulae of the relaxation times expressed in terms of relaxation functions which allow a natural physical interpretation of the relaxation times. Furthermore, our theory nicely gives the explicit forms of the distribution function and the thirteen hydrodynamic variables in terms of the linearized collision operator, which in turn clearly suggest the proper ansatz forms of them to be adopted in the method of moments.

  6. (3+1)-dimensional framework for leading-order non conformal anisotropic hydrodynamics

    E-Print Network [OSTI]

    Leonardo Tinti

    2015-05-24T23:59:59.000Z

    In this work I develop a new framework for anisotropic hydrodynamics that generalizes the leading order of the hydrodynamic expansion to the full (3+1)-dimensional anisotropic massive case. Following previous works, my considerations are based on the Boltzmann kinetic equation with the collisional term treated in the relaxation time approximation. The momentum anisotropy is included explicitly in the leading term, allowing for a large difference between the longitudinal and transverse pressures as well as for non trivial transverse dynamics. Energy and momentum conservation is expressed by the first moment of the Boltzmann equation. The system of equations is closed by using the zeroth and second moments of the Boltzmann equation. The close-to-equilibrium matching with second-order viscous hydrodynamics is demonstrated. In particular, I show that the coupling between shear and bulk pressure corrections, recently proved to be important for an accurate description of momentum anisotropy and bulk viscous dynamics, does not vanish in the close-to-equilibrium limit.

  7. Experimental and computational studies of hydrodynamics in three-phase and two-phase fluidized beds

    SciTech Connect (OSTI)

    Bahary, M.

    1994-12-01T23:59:59.000Z

    The objective of the present study was to investigate the hydrodynamics of three-phase fluidized beds, their rheology, and experimentally verify a predictive three fluid hydrodynamic model developed at the Illinois Institute of Technology, Chicago. The recent reviews show that there exist no such models in the literature. The IIT hydrodynamic model computes the phase velocities and the volume fractions of gas, liquid, and particulate phases. Model verification involves a comparison of these computed velocities and volume fractions to experimental values. In this thesis, a three fluid model is presented. The input into the model can be particulate viscosities either measured with a Brookfield viscometer or derived using the mathematical techniques of kinetic theory of granular flows pioneered by Savage and others. The computer simulation of a three-phase fluidized bed in an asymmetric mode qualitatively predicts the gas, liquid and solid hold-ups (volume fractions) and flow patterns in the industrially important churn-turbulent (bubbly coalesced) regimes. The computations in a fluidized bed with a symmetric distributor incorrectly showed no bubble coalescence. A combination of X-ray and {gamma}-ray densitometers was used to measure the solids and the liquid volume fractions in a two dimensional bed in the bubble coalesced regime. There is a good agreement between the theory for an asymmetric distributor and the experiments.

  8. Hydrodynamic flow in the vicinity of a nanopore induced by an applied voltage

    E-Print Network [OSTI]

    Mao Mao; Sandip Ghosal; Guohui Hu

    2013-05-16T23:59:59.000Z

    Continuum simulation is employed to study ion transport and fluid flow through a nanopore in a solid-state membrane under an applied potential drop. Results show the existence of concentration polarization layers on the surfaces of the membrane. The nonuniformity of the ionic distribution gives rise to an electric pressure that drives vortical motion in the fluid. There is also a net hydrodynamic flow through the nanopore due to an asymmetry induced by the membrane surface charge. The qualitative behavior is similar to that observed in a previous study using molecular dynamic simulations. The current--voltage characteristics show some nonlinear features but are not greatly affected by the hydrodynamic flow in the parameter regime studied. In the limit of thin Debye layers, the electric resistance of the system can be characterized using an equivalent circuit with lumped parameters. Generation of vorticity can be understood qualitatively from elementary considerations of the Maxwell stresses. However, the flow strength is a strongly nonlinear function of the applied field. Combination of electrophoretic and hydrodynamic effects can lead to ion selectivity in terms of valences and this could have some practical applications in separations.

  9. Development of a Hydrodynamic Model for Skagit River Estuary for Estuarine Restoration Feasibility Assessment

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Liu, Hedong; Khangaonkar, Tarang P.

    2006-08-03T23:59:59.000Z

    The Skagit River is the largest river in the Puget Sound estuarine system. It discharges about 39% of total sediment and more than 20% of freshwater into Puget Sound. The Skagit River delta provides rich estuarine and freshwater habitats for salmon and many other wildlife species. Over the past 150 years, economic development in the Skagit River delta has resulted in significant losses of wildlife habitat, particularly due to construction of dikes. Diked portion of the delta is known as Fir Island where irrigation practices for agriculture land over the last century has resulted in land subsidence. This has also caused reduced efficiency of drainage network and impeded fish passages through the area. In this study, a three-dimensional tidal circulation model was developed for the Skagit River delta to assist estuarine restoration in the Fir Island area. The hydrodynamic model used in the study is the Finite Volume Coastal Ocean Model (FVCOM). The hydrodynamic model was calibrated using field data collected from the study area specifically for the model development. Wetting and drying processes in the estuarine delta are simulated in the hydrodynamic model. The calibrated model was applied to simulate different restoration alternatives and provide guidance for estuarine restoration and management. Specifically, the model was used to help select and design configurations that would improve the supply of sediment and freshwater to the mudflats and tidal marsh areas outside of diked regions and then improve the estuarine habitats for salmon migration.

  10. Puget Sound Dissolved Oxygen Modeling Study: Development of an Intermediate-Scale Hydrodynamic Model

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Khangaonkar, Tarang; Labiosa, Rochelle G.; Kim, Taeyun

    2010-11-30T23:59:59.000Z

    The Washington State Department of Ecology contracted with Pacific Northwest National Laboratory to develop an intermediate-scale hydrodynamic and water quality model to study dissolved oxygen and nutrient dynamics in Puget Sound and to help define potential Puget Sound-wide nutrient management strategies and decisions. Specifically, the project is expected to help determine 1) if current and potential future nitrogen loadings from point and non-point sources are significantly impairing water quality at a large scale and 2) what level of nutrient reductions are necessary to reduce or dominate human impacts to dissolved oxygen levels in the sensitive areas. In this study, an intermediate-scale hydrodynamic model of Puget Sound was developed to simulate the hydrodynamics of Puget Sound and the Northwest Straits for the year 2006. The model was constructed using the unstructured Finite Volume Coastal Ocean Model. The overall model grid resolution within Puget Sound in its present configuration is about 880 m. The model was driven by tides, river inflows, and meteorological forcing (wind and net heat flux) and simulated tidal circulations, temperature, and salinity distributions in Puget Sound. The model was validated against observed data of water surface elevation, velocity, temperature, and salinity at various stations within the study domain. Model validation indicated that the model simulates tidal elevations and currents in Puget Sound well and reproduces the general patterns of the temperature and salinity distributions.

  11. The core helium flash revisited: I. One and two-dimensional hydrodynamic simulations

    E-Print Network [OSTI]

    M. Mocak; E. Mueller; A. Weiss; K. Kifonidis

    2008-05-09T23:59:59.000Z

    We investigate the hydrodynamics of the core helium flash near its peak. Past research concerned with the dynamics of this event is inconclusive. However, the most recent multidimensional hydrodynamic studies suggest a quiescent behavior and seem to rule out an explosive scenario. Previous work indicated, that depending on initial conditions, employed turbulence models, grid resolution, and dimensionality of the simulation, the core helium flash leads either to the disruption of a low-mass star or to a quiescent quasi-hydrostatic evolution. We try to clarify this issue by simulating the evolution with advanced numerical methods and detailed microphysics. Assuming spherical or axial symmetry, we simulate the evolution of the helium core of a $1.25 M_{\\odot}$ star with a metallicity Z=0.02 during the core helium flash at its peak with a grid-based hydrodynamics code. We find that the core helium flash neither rips the star apart, nor that it significantly alters its structure, as convection plays a crucial role in keeping the star in hydrostatic equilibrium. In addition, our simulations show the presence of overshooting, which implies new predictions concerning mixing of chemical species in red giants.

  12. Non-linear hydrodynamics of axion dark matter: relative velocity effects and "quantum forces"

    E-Print Network [OSTI]

    Marsh, David J E

    2015-01-01T23:59:59.000Z

    The non-linear hydrodynamic equations for axion/scalar field dark matter (DM) in the non-relativistic Madelung-Shcr\\"{o}dinger form are derived in a simple manner, including the effects of universal expansion and Hubble drag. The hydrodynamic equations are used to investigate the relative velocity between axion DM and baryons, and the moving-background perturbation theory (MBPT) derived. Axions massive enough to be all of the DM do not affect the coherence length of the relative velocity, but the MBPT equations are modified by the inclusion of the axion effective sound speed. These MBPT equations are necessary for accurately modelling the effects of axion DM on the formation of the first cosmic structures, and suggest that the 21cm power spectrum could improve constraints on axion mass by up to four orders of magnitude with respect to the current best constraints. A further application of these results uses the "quantum force" analogy to model scalar field gradient energy in a smoothed-particle hydrodynamics ...

  13. Thermal hydraulic performance testing of printed circuit heat exchangers in a high-temperature helium test facility

    SciTech Connect (OSTI)

    Sai K. Mylavarapu; Xiaodong Sun; Richard E. Glosup; Richard N. Christensen; Michael W. Patterson

    2014-04-01T23:59:59.000Z

    In high-temperature gas-cooled reactors, such as a very high temperature reactor (VHTR), an intermediate heat exchanger (IHX) is required to efficiently transfer the core thermal output to a secondary fluid for electricity generation with an indirect power cycle and/or process heat applications. Currently, there is no proven high-temperature (750–800 °C or higher) compact heat exchanger technology for high-temperature reactor design concepts. In this study, printed circuit heat exchanger (PCHE), a potential IHX concept for high-temperature applications, has been investigated for their heat transfer and pressure drop characteristics under high operating temperatures and pressures. Two PCHEs, each having 10 hot and 10 cold plates with 12 channels (semicircular cross-section) in each plate are fabricated using Alloy 617 plates and tested for their performance in a high-temperature helium test facility (HTHF). The PCHE inlet temperature and pressure were varied from 85 to 390 °C/1.0–2.7 MPa for the cold side and 208–790 °C/1.0–2.7 MPa for the hot side, respectively, while the mass flow rate of helium was varied from 15 to 49 kg/h. This range of mass flow rates corresponds to PCHE channel Reynolds numbers of 950 to 4100 for the cold side and 900 to 3900 for the hot side (corresponding to the laminar and laminar-to-turbulent transition flow regimes). The obtained experimental data have been analyzed for the pressure drop and heat transfer characteristics of the heat transfer surface of the PCHEs and compared with the available models and correlations in the literature. In addition, a numerical treatment of hydrodynamically developing and hydrodynamically fully-developed laminar flow through a semicircular duct is presented. Relations developed for determining the hydrodynamic entrance length in a semicircular duct and the friction factor (or pressure drop) in the hydrodynamic entry length region for laminar flow through a semicircular duct are given. Various hydrodynamic entrance region parameters, such as incremental pressure drop number, apparent Fanning friction factor, and hydrodynamic entrance length in a semicircular duct have been numerically estimated.

  14. Proceedings of RIKEN BNL Research Center Workshop entitled Hydrodynamics in Heavy Ion Collisions and QCD Equation of State (Volume 88)

    SciTech Connect (OSTI)

    Karsch,F.; Kharzeev, D.; Molnar, K.; Petreczky, P.; Teaney, D.

    2008-04-21T23:59:59.000Z

    The interpretation of relativistic heavy-ion collisions at RHIC energies with thermal concepts is largely based on the relative success of ideal (nondissipative) hydrodynamics. This approach can describe basic observables at RHIC, such as particle spectra and momentum anisotropies, fairly well. On the other hand, recent theoretical efforts indicate that dissipation can play a significant role. Ideally viscous hydrodynamic simulations would extract, if not only the equation of state, but also transport coefficients from RHIC data. There has been a lot of progress with solving relativistic viscous hydrodynamics. There are already large uncertainties in ideal hydrodynamics calculations, e.g., uncertainties associated with initial conditions, freezeout, and the simplified equations of state typically utilized. One of the most sensitive observables to the equation of state is the baryon momentum anisotropy, which is also affected by freezeout assumptions. Up-to-date results from lattice quantum chromodynamics on the transition temperature and equation of state with realistic quark masses are currently available. However, these have not yet been incorporated into the hydrodynamic calculations. Therefore, the RBRC workshop 'Hydrodynamics in Heavy Ion Collisions and QCD Equation of State' aimed at getting a better understanding of the theoretical frameworks for dissipation and near-equilibrium dynamics in heavy-ion collisions. The topics discussed during the workshop included techniques to solve the dynamical equations and examine the role of initial conditions and decoupling, as well as the role of the equation of state and transport coefficients in current simulations.

  15. Hydrodynamic Simulation of the Columbia River, Hanford Reach, 1940--2004

    SciTech Connect (OSTI)

    Waichler, Scott R.; Perkins, William A.; Richmond, Marshall C.

    2005-06-15T23:59:59.000Z

    Many hydrological and biological problems in the Columbia River corridor through the Hanford Site require estimates of river stage (water surface elevation) or river flow and velocity. Systematic collection of river stage data at locations in the Hanford Reach began in 1991, but many environmental projects need river stage information at unmeasured locations or over longer time periods. The Modular Aquatic Simulation System 1D (MASS1), a one-dimensional, unsteady hydrodynamic and water quality model, was used to simulate the Columbia River from Priest Rapids Dam to McNary Dam from 1940 to 2004, providing estimates of water surface elevation, volumetric flow rate, and flow velocity at 161 locations on the Hanford Reach. The primary input data were bathymetric/topographic cross sections of the Columbia River channel, flow rates at Priest Rapids Dam, and stage at McNary Dam. Other inputs included Yakima River and Snake River inflows. Available flow data at a gaging station just below Priest Rapids Dam was mean daily flow from 1940 to 1986 and hourly thereafter. McNary dam was completed in 1957, and hourly stage data are available beginning in 1975. MASS1 was run at an hourly timestep and calibrated and tested using 1991--2004 river stage data from six Hanford Reach locations (areas 100B, 100N, 100D, 100H, 100F, and 300). Manning's roughness coefficient in the Reach above each river recorder location was adjusted using an automated genetic algorithm and gradient search technique in three separate calibrations, corresponding to different data subsets, with minimization of mean absolute error as the objective. The primary calibration was based on 1999, a representative year, and included all locations. The first alternative calibration also used all locations but was limited in time to a high-flow period during spring and early summer of 1997. The second alternative calibration was based on 1999 and included only 300 Area stage data. Model goodness-of-fit for all years with data was high in the primary calibration and indicated little bias caused by selecting 1999. The alternative calibrations led to improved goodness-of-fit for their limited time and locations, but degraded goodness-of-fit overall. Overall, the simulations were very accurate and even highlighted some probable data problems, as evidenced by systematic shifts in the data. Further improvements in simulating the historic period would depend on correcting these inferred data problems. For all years and locations, the mean absolute error in the primary calibration was 14.8 cm, the mean error was 1 mm, and model efficiency was 0.988. The MASS1 output for 1940--2004 can be used to reconstruct historical river elevations at Hanford or to build scenarios of future river elevations for solving environmental problems such as groundwater-river interaction or fish habitat inventories. Model output and additional processing services are available from the authors. Longer-term scenarios extending more than a few decades from now should also consider the impacts of climate change and reservoir operation change. Once defined, these impacts could be used to drive new simulations with MASS1.

  16. Test Comparability

    E-Print Network [OSTI]

    Keller, Christine; Shulenburger, David E.

    2010-01-01T23:59:59.000Z

    KU ScholarWorks | http://kuscholarworks.ku.edu Test Comparability 2010 by Christine Keller and David Shulenburger This work has been made available by the University of Kansas Libraries’ Office of Scholarly Communication and Copyright. Please... and Shulenburger, David. “Test comparability,” with Christine Keller in the Letters section of Change, September/October 2010, p. 6. Published version: http://www.changemag.org/Archives/Back%20 Issues/September-October%202010/letters-to-editor.html Terms of Use...

  17. Test Automation Ant JUnit Test Automation

    E-Print Network [OSTI]

    Mousavi, Mohammad

    Test Automation Ant JUnit Test Automation Mohammad Mousavi Eindhoven University of Technology, The Netherlands Software Testing 2012 Mousavi: Test Automation #12;Test Automation Ant JUnit Outline Test Automation Ant JUnit Mousavi: Test Automation #12;Test Automation Ant JUnit Why? Challenges of Manual Testing

  18. Dynamics of suspensions of hydrodynamically structured particles: Analytic theory and experiment

    E-Print Network [OSTI]

    Jonas Riest; Thomas Eckert; Walter Richtering; Gerhard Nägele

    2015-01-12T23:59:59.000Z

    We present an easy-to-use analytic toolbox for the calculation of short-time transport properties of concentrated suspensions of spherical colloidal particles with internal hydrodynamic structure, and direct interactions described by a hard-core or soft Hertz pair potential. The considered dynamic properties include self-diffusion and sedimentation coefficients, the wavenumber-dependent diffusion function determined in dynamic scattering experiments, and the high-frequency shear viscosity. The toolbox is based on the hydrodynamic radius model (HRM) wherein the internal particle structure is mapped on a hydrodynamic radius parameter for unchanged direct interactions, and on an existing simulation data base for solvent-permeable and spherical annulus particles. Useful scaling relations for the diffusion function and self-diffusion coefficient, known to be valid for hard-core interaction, are shown to apply also for soft pair potentials. We further discuss extensions of the toolbox to long-time transport properties including the low-shear zero-frequency viscosity and the long-time self-diffusion coefficient. The versatility of the toolbox is demonstrated by the analysis of a previous light scattering study of suspensions of non-ionic PNiPAM microgels [Eckert et al., J. Chem. Phys., 2008, 129, 124902] in which a detailed theoretical analysis of the dynamic data was left as an open task. By the comparison with Hertz potential based calculations, we show that the experimental data are consistently and accurately described using the Verlet-Weis corrected Percus-Yevick structure factor as input, and for a solvent penetration length equal to three percent of the excluded volume radius. This small solvent permeability of the microgel particles has a significant dynamic effect at larger concentrations.

  19. Iterative linear solvers in a 2D radiation-hydrodynamics code: Methods and performance

    SciTech Connect (OSTI)

    Baldwin, C.; Brown, P.N.; Falgout, R.; Graziani, F.; Jones, J.

    1999-09-01T23:59:59.000Z

    Computer codes containing both hydrodynamics and radiation play a central role in simulating both astrophysical and inertial confinement fusion (ICF) phenomena. A crucial aspect of these codes is that they require an implicit solution of the radiation diffusion equations. The authors present in this paper the results of a comparison of five different linear solvers on a range of complex radiation and radiation-hydrodynamics problems. The linear solvers used are diagonally scaled conjugate gradient, GMRES with incomplete LU preconditioning, conjugate gradient with incomplete Cholesky preconditioning, multigrid, and multigrid-preconditioned conjugate gradient. These problems involve shock propagation, opacities varying over 5--6 orders of magnitude, tabular equations of state, and dynamic ALE (Arbitrary Lagrangian Eulerian) meshes. They perform a problem size scalability study by comparing linear solver performance over a wide range of problem sizes from 1,000 to 100,000 zones. The fundamental question they address in this paper is: Is it more efficient to invert the matrix in many inexpensive steps (like diagonally scaled conjugate gradient) or in fewer expensive steps (like multigrid)? In addition, what is the answer to this question as a function of problem size and is the answer problem dependent? They find that the diagonally scaled conjugate gradient method performs poorly with the growth of problem size, increasing in both iteration count and overall CPU time with the size of the problem and also increasing for larger time steps. For all problems considered, the multigrid algorithms scale almost perfectly (i.e., the iteration count is approximately independent of problem size and problem time step). For pure radiation flow problems (i.e., no hydrodynamics), they see speedups in CPU time of factors of {approx}15--30 for the largest problems, when comparing the multigrid solvers relative to diagonal scaled conjugate gradient.

  20. Simplified 1-D Hydrodynamic and Salinity Transport Modeling of the Sacramento–San Joaquin Delta: Sea Level Rise and Water Diversion Effects

    E-Print Network [OSTI]

    Fleenor, William E.; Bombardelli, Fabian

    2013-01-01T23:59:59.000Z

    Hydrodynamic and Salinity Transport Modeling of the Sacramento–San Joaquinhydrodynamic and salinity transport mod- eling of the Sacramento–San Joaquin

  1. Verification Testing Test Driven Development Testing with JUnit Verification

    E-Print Network [OSTI]

    Peters, Dennis

    Verification Testing Test Driven Development Testing with JUnit Verification Any activity should be verified. #12;Verification Testing Test Driven Development Testing with JUnit Approaches to verification 1 Testing 2 Static Analysis · Peer review · Insepction/Walk-through/Structured review · Formal

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

    E-Print Network [OSTI]

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

    2004-07-23T23:59:59.000Z

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

  3. Simulating Rayleigh-Taylor (RT) instability using PPM hydrodynamics @scale on Roadrunner (u)

    SciTech Connect (OSTI)

    Woodward, Paul R [Los Alamos National Laboratory; Dimonte, Guy [Los Alamos National Laboratory; Rockefeller, Gabriel M [Los Alamos National Laboratory; Fryer, Christopher L [Los Alamos National Laboratory; Dimonte, Guy [Los Alamos National Laboratory; Dai, W [Los Alamos National Laboratory; Kares, R. J. [Los Alamos National Laboratory

    2011-01-05T23:59:59.000Z

    The effect of initial conditions on the self-similar growth of the RT instability is investigated using a hydrodynamics code based on the piecewise-parabolic-method (PPM). The PPM code was converted to the hybrid architecture of Roadrunner in order to perform the simulations at extremely high speed and spatial resolution. This paper describes the code conversion to the Cell processor, the scaling studies to 12 CU's on Roadrunner and results on the dependence of the RT growth rate on initial conditions. The relevance of the Roadrunner implementation of this PPM code to other existing and anticipated computer architectures is also discussed.

  4. Dense granular flow around a penetrating object: Experiments and hydrodynamic model

    E-Print Network [OSTI]

    Antoine Seguin; Yann Bertho; Philippe Gondret; Jerome Crassous

    2011-06-24T23:59:59.000Z

    We present in this Letter experimental results on the bidimensional flow field around a cylinder penetrating into dense granular matter together with drag force measurements. A hydrodynamic model based on extended kinetic theory for dense granular flow reproduces well the flow localization close to the cylinder and the corresponding scalings of the drag force, which is found to not depend on velocity, but linearly on the pressure and on the cylinder diameter and weakly on the grain size. Such a regime is found to be valid at a low enough "granular" Reynolds number.

  5. Hydrodynamic radial and elliptic flow in heavy-ion collisions from AGS to LHC energies

    E-Print Network [OSTI]

    Gregory Kestin; Ulrich W Heinz

    2008-11-28T23:59:59.000Z

    Using ideal relativistic hydrodynamics in 2+1 dimensions, we study the collision energy dependence of radial and elliptic flow, of the emitted hadron spectra, and of the transverse momentum dependence of several hadronic particle ratios, covering the range from Alternating Gradient Synchrotron (AGS) to Large Hadron Collider (LHC) energies. These calculations establish an ideal fluid dynamic baseline that can be used to assess non-equilibrium features manifest in future LHC heavy-ion experiments. Contrary to earlier suggestions we find that a saturation and even decrease of the differential elliptic flow v_2(p_T) with increasing collision energy cannot be unambiguously associated with the QCD phase transition.

  6. Transport coefficients of off-lattice mesoscale-hydrodynamics simulation techniques

    E-Print Network [OSTI]

    Hiroshi Noguchi; Gerhard Gompper

    2008-04-14T23:59:59.000Z

    The viscosity and self-diffusion constant of particle-based mesoscale hydrodynamic methods, multi-particle collision dynamics (MPC) and dissipative particle dynamics (DPD), are investigated, both with and without angular-momentum conservation. Analytical results are derived for fluids with an ideal-gas equation of state and a finite-time-step dynamics, and compared with simulation data. In particular, the viscosity is derived in a general form for all variants of the MPC method. In general, very good agreement between theory and simulations is obtained.

  7. Effect of charged particle's multiplicity fluctuations on flow harmonics in even-by-event hydrodynamics

    E-Print Network [OSTI]

    Chaudhuri, A K

    2012-01-01T23:59:59.000Z

    In nucleon-nucleon collisions, charged particle's multiplicity fluctuates. We have studied the effect of multiplicity fluctuation on flow harmonics in nucleus-nucleus collision in event-by-event hydrodynamics. Assuming that the charged particle's multiplicity fluctuations are governed by the negative binomial distribution, the Monte-Carlo Glauber model of initial condition is generalised to include the fluctuations. Explicit simulations with the generalised Monte-Carlo Glauber model initial conditions indicate that the multiplicity fluctuations do not have large effect on the flow harmonics.

  8. Effect of charged particle's multiplicity fluctuations on flow harmonics in even-by-event hydrodynamics

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2013-03-19T23:59:59.000Z

    In nucleon-nucleon collisions, charged particle's multiplicity fluctuates. We have studied the effect of multiplicity fluctuation on flow harmonics in nucleus-nucleus collision in event-by-event hydrodynamics. Assuming that the charged particle's multiplicity fluctuations are governed by the negative binomial distribution, the Monte-Carlo Glauber model of initial condition is generalised to include the fluctuations. Explicit simulations with the generalised Monte-Carlo Glauber model initial conditions indicate that the multiplicity fluctuations do not have large effect on the flow harmonics.

  9. Knudsen-Hydrodynamic Crossover in Liquid 3He in High Porosity Aerogel

    E-Print Network [OSTI]

    Takeuchi, H; Nagai, K; Choi, H C; Moon, B H; Masuhara, N; Meisel, M W; Lee, Y; Mulders, N

    2012-01-01T23:59:59.000Z

    We present a combined experimental and theoretical study of the drag force acting on a high porosity aerogel immersed in liquid ${}^3$He and its effect on sound propagation. The drag force is characterized by the Knudsen number, which is defined as the ratio of the quasiparticle mean free path to the radius of an aerogel strand. Evidence of the Knudsen-hydrodynamic crossover is clearly demonstrated by a drastic change in the temperature dependence of ultrasound attenuation in 98% porosity aerogel. Our theoretical analysis shows that the frictional sound damping caused by the drag force is governed by distinct laws in the two regimes, providing excellent agreement with the experimental observation.

  10. Hydrodynamic Relaxation of an Electron Plasma to a Near-Maximum Entropy State

    SciTech Connect (OSTI)

    Rodgers, D. J.; Servidio, S.; Matthaeus, W. H.; Mitchell, T. B.; Aziz, T. [Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States); Montgomery, D. C. [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States)

    2009-06-19T23:59:59.000Z

    Dynamical relaxation of a pure electron plasma in a Malmberg-Penning trap is studied, comparing experiments, numerical simulations and statistical theories of weakly dissipative two-dimensional (2D) turbulence. Simulations confirm that the dynamics are approximated well by a 2D hydrodynamic model. Statistical analysis favors a theoretical picture of relaxation to a near-maximum entropy state with constrained energy, circulation, and angular momentum. This provides evidence that 2D electron fluid relaxation in a turbulent regime is governed by principles of maximum entropy.

  11. Report of independent consultants reviewing Integrated Test Stands (ITS) performance and readiness of DARHT for construction start

    SciTech Connect (OSTI)

    Not Available

    1993-08-01T23:59:59.000Z

    Independent consultants met at Los Alamos, June 15 and 16, 1993, to review progress on the commissioning of the Integrated Test Stand (ITS) for DARHT and to provide DOE with technical input on readiness for construction of the first radiographic arm of DARHT. The consultants concluded that all milestones necessary for demonstrating the performance of the DARHT accelerator have been met and that the project is ready for construction to resume. The experimental program using ITS should be continued to quantify the comparison of experiment and theory, to test improvements on the injector insulator, and to better evaluate the interaction of the beam and the target.

  12. Quantum Hydrodynamics

    E-Print Network [OSTI]

    Khan, Shabbir A

    2013-01-01T23:59:59.000Z

    Quantum plasma physics is a rapidly evolving research field with a very inter-disciplinary scope of potential applications, ranging from nano-scale science in condensed matter to the vast scales of astrophysical objects. The theoretical description of quantum plasmas relies on various approaches, microscopic or macroscopic, some of which have obvious relation to classical plasma models. The appropriate model should, in principle, incorporate the quantum mechanical effects such as diffraction, spin statistics and correlations, operative on the relevant scales. However, first-principle approaches such as quantum Monte Carlo and density functional theory or quantum-statistical methods such as quantum kinetic theory or non-equilibrium Green's functions require substantial theoretical and computational efforts. Therefore, for selected problems, alternative simpler methods have been put forward. In particular, the collective behavior of many-body systems is usually described within a self-consistent scheme of parti...

  13. Improving the hot-spot pressure and demonstrating ignition hydrodynamic equivalence in cryogenic deuterium–tritium implosions on OMEGA

    SciTech Connect (OSTI)

    Goncharov, V. N.; Sangster, T. C.; Betti, R.; Boehly, T. R.; Bonino, M. J.; Collins, T. J. B.; Craxton, R. S.; Delettrez, J. A.; Edgell, D. H.; Epstein, R.; Follett, R. K.; Forrest, C. J.; Froula, D. H.; Glebov, V. Yu.; Harding, D. R.; Henchen, R. J.; Hu, S. X.; Igumenshchev, I. V.; Janezic, R.; Kelly, J. H. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); and others

    2014-05-15T23:59:59.000Z

    Reaching ignition in direct-drive (DD) inertial confinement fusion implosions requires achieving central pressures in excess of 100 Gbar. The OMEGA laser system [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] is used to study the physics of implosions that are hydrodynamically equivalent to the ignition designs on the National Ignition Facility (NIF) [J. A. Paisner et al., Laser Focus World 30, 75 (1994)]. It is shown that the highest hot-spot pressures (up to 40 Gbar) are achieved in target designs with a fuel adiabat of ? ? 4, an implosion velocity of 3.8?×?10{sup 7}?cm/s, and a laser intensity of ?10{sup 15}?W/cm{sup 2}. These moderate-adiabat implosions are well understood using two-dimensional hydrocode simulations. The performance of lower-adiabat implosions is significantly degraded relative to code predictions, a common feature between DD implosions on OMEGA and indirect-drive cryogenic implosions on the NIF. Simplified theoretical models are developed to gain physical understanding of the implosion dynamics that dictate the target performance. These models indicate that degradations in the shell density and integrity (caused by hydrodynamic instabilities during the target acceleration) coupled with hydrodynamics at stagnation are the main failure mechanisms in low-adiabat designs. To demonstrate ignition hydrodynamic equivalence in cryogenic implosions on OMEGA, the target-design robustness to hydrodynamic instability growth must be improved by reducing laser-coupling losses caused by cross beam energy transfer.

  14. Verifying Test Hypotheses -HOL/TestGen Verifying Test Hypotheses -HOL/TestGen

    E-Print Network [OSTI]

    Verifying Test Hypotheses - HOL/TestGen Verifying Test Hypotheses - HOL/TestGen An Experiment in Test and Proof Thomas Malcher January 20, 2014 1 / 20 #12;Verifying Test Hypotheses - HOL/TestGen HOL/TestGen Outline Introduction Test Hypotheses HOL/TestGen - Demo Verifying Test Hypotheses Conclusion 2 / 20 #12

  15. Hydrodynamic interactions in metal rod-like particle suspensions due to induced charge electroosmosis

    SciTech Connect (OSTI)

    Rose, K A; Hoffman, B; Saintillan, D; Shaqfeh, E G; Santiago, J G

    2008-05-05T23:59:59.000Z

    We present a theoretical and experimental study of the role of hydrodynamic interactions on the motion and dispersion of metal rod-like particles in the presence of an externally applied electric field. In these systems, the electric field polarizes the particles and induces an electroosmosis flow relative to the surface of each particle. The simulations include the effect of the gravitational body force, buoyancy, far-field hydrodynamic interactions, near-field lubrication forces, and electric field interactions. The particles in the simulations and experiments were observed to experience repeated pairing interactions in which they come together axially with their ends approaching each other, slide past one another until their centers approach, and then push apart. These interactions were confirmed in measurements of particle orientations and velocities, pair distribution functions, and net dispersion of the suspension. For large electric fields, the pair distribution functions show accumulation and depletion regions consistent with many pairing events. For particle concentrations of 1e8 particles/mL and higher, dispersion within the suspension dramatically increases with increased field strength.

  16. Selective evaporation of focusing fluid in two-fluid hydrodynamic print head.

    SciTech Connect (OSTI)

    Keicher, David M.; Cook, Adam W.

    2014-09-01T23:59:59.000Z

    The work performed in this project has demonstrated the feasibility to use hydrodynamic focusing of two fluid steams to create a novel micro printing technology for electronics and other high performance applications. Initial efforts focused solely on selective evaporation of the sheath fluid from print stream provided insight in developing a unique print head geometry allowing excess sheath fluid to be separated from the print flow stream for recycling/reuse. Fluid flow models suggest that more than 81 percent of the sheath fluid can be removed without affecting the print stream. Further development and optimization is required to demonstrate this capability in operation. Print results using two-fluid hydrodynamic focusing yielded a 30 micrometers wide by 0.5 micrometers tall line that suggests that the cross-section of the printed feature from the print head was approximately 2 micrometers in diameter. Printing results also demonstrated that complete removal of the sheath fluid is not necessary for all material systems. The two-fluid printing technology could enable printing of insulated conductors and clad optical interconnects. Further development of this concept should be pursued.

  17. Development of a Hydrodynamic Model of Puget Sound and Northwest Straits

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Khangaonkar, Tarang P.

    2007-12-10T23:59:59.000Z

    The hydrodynamic model used in this study is the Finite Volume Coastal Ocean Model (FVCOM) developed by the University of Massachusetts at Dartmouth. The unstructured grid and finite volume framework, as well as the capability of wetting/drying simulation and baroclinic simulation, makes FVCOM a good fit to the modeling needs for nearshore restoration in Puget Sound. The model domain covers the entire Puget Sound, Strait of Juan de Fuca, San Juan Passages, and Georgia Strait at the United States-Canada Border. The model is driven by tide, freshwater discharge, and surface wind. Preliminary model validation was conducted for tides at various locations in the straits and Puget Sound using National Oceanic and Atmospheric Administration (NOAA) tide data. The hydrodynamic model was successfully linked to the NOAA oil spill model General NOAA Operational Modeling Environment model (GNOME) to predict particle trajectories at various locations in Puget Sound. Model results demonstrated that the Puget Sound GNOME model is a useful tool to obtain first-hand information for emergency response such as oil spill and fish migration pathways.

  18. Hydrodynamic Effects in the Symmetron and $f(R)$-gravity Models

    E-Print Network [OSTI]

    Amir Hammami; Claudio Llinares; David F. Mota; Hans A. Winther

    2015-03-06T23:59:59.000Z

    In this paper we present the first results from implementing two scalar-tensor modified gravity theories, the symmetron and the Hu-Sawicki $f(R)$-gravity model, into a hydrodynamic N-body code with dark matter particles and a baryonic ideal gas. The study is a continuation of previous work where the symmetron and $f(R)$ have been successfully implemented in the RAMSES code, but for dark matter only. By running simulations, we show that the deviation from $\\Lambda$CDM in these models for the gas density profiles are significantly lower than the dark matter equivalents. When it comes to the matter power-spectrum we find that hydrodynamic simulations agree very well with dark matter only simulations as long as we consider scales larger than $k\\sim 0.5$ h/Mpc. In general the effects of modified gravity on the baryonic gas is found to not always mirror the effects it has on the dark matter. The largest signature is found when considering temperature profiles. We find that the gas temperatures in the modified gravity model studied here show deviations, when compared to $\\Lambda$CDM, that can be a factor of a few larger than the deviations found in density profiles and power spectra.

  19. Quasi-periodic oscillations as global hydrodynamic modes in the boundary layers of viscous accretion disks

    E-Print Network [OSTI]

    M. Hakan Erkut; Dimitrios Psaltis; M. Ali Alpar

    2008-07-28T23:59:59.000Z

    The observational characteristics of quasi-periodic oscillations (QPOs) from accreting neutron stars strongly indicate the oscillatory modes in the innermost regions of accretion disks as a likely source of the QPOs. The inner regions of accretion disks around neutron stars can harbor very high frequency modes related to the radial epicyclic frequency $\\kappa $. The degeneracy of $\\kappa $ with the orbital frequency $\\Omega $ is removed in a non-Keplerian boundary or transition zone near the magnetopause between the disk and the compact object. We show, by analyzing the global hydrodynamic modes of long wavelength in the boundary layers of viscous accretion disks, that the fastest growing mode frequencies are associated with frequency bands around $\\kappa $ and $\\kappa \\pm \\Omega $. The maximum growth rates are achieved near the radius where the orbital frequency $\\Omega $ is maximum. The global hydrodynamic parameters such as the surface density profile and the radial drift velocity determine which modes of free oscillations will grow at a given particular radius in the boundary layer. In accordance with the peak separation between kHz QPOs observed in neutron-star sources, the difference frequency between two consecutive bands of the fastest growing modes is always related to the spin frequency of the neutron star. This is a natural outcome of the boundary condition imposed by the rotating magnetosphere on the boundary region of the inner disk.

  20. Jet Propagation and Mach-Cone Formation in (3+1)-dimensional Ideal Hydrodynamics

    E-Print Network [OSTI]

    Barbara Betz

    2009-10-20T23:59:59.000Z

    This thesis investigates the jet-medium interactions in a Quark-Gluon Plasma using a hydrodynamical model. It deals with the creation of Mach cones which are supposed to exhibit a characteristic structure in the measured angular particle distributions allowing for direct conclusions about the Equation of State and in particular about the speed of sound of the medium. Several different scenarios of jet energy loss are examined and different mechanisms of energy and momentum loss are analyzed, ranging from weak interactions (based on calculations from perturbative Quantum Chromodynamics, pQCD) to strong interactions (formulated using the Anti-de-Sitter/Conformal Field Theory Correspondence, AdS/CFT). Though they result in different angular particle correlations which could in principle allow to distinguish the underlying processes, it is shown that the characteristic structure observed in experimental data can be obtained due to the different contributions of several possible jet trajectories through an expanding medium. Such a structure cannot directly be connected to the Equation of State. In this context, the impact of a strong flow created behind the jet (the diffusion wake) is examined which is common to almost all jet deposition scenarios. Besides that, the transport equations for dissipative hydrodynamics are discussed which are fundamental for any numerical computation of viscous effects in a Quark-Gluon Plasma.

  1. Hydrodynamic instability growth and mix experiments at the National Ignition Facility

    SciTech Connect (OSTI)

    Smalyuk, V. A.; Barrios, M.; Caggiano, J. A.; Casey, D. T.; Cerjan, C. J.; Clark, D. S.; Edwards, M. J.; Haan, S. W.; Hammel, B. A.; Hamza, A.; Hsing, W. W.; Hurricane, O.; Kroll, J.; Landen, O. L.; Lindl, J. D.; Ma, T.; McNaney, J. M.; Mintz, M.; Parham, T.; Peterson, J. L. [Lawrence Livermore National Laboratory, NIF Directorate, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, NIF Directorate, Livermore, California 94550 (United States); and others

    2014-05-15T23:59:59.000Z

    Hydrodynamic instability growth and its effects on implosion performance were studied at the National Ignition Facility [G. H. Miller, E. I. Moses, and C. R. Wuest, Opt. Eng. 443, 2841 (2004)]. Implosion performance and mix have been measured at peak compression using plastic shells filled with tritium gas and containing embedded localized carbon-deuterium diagnostic layers in various locations in the ablator. Neutron yield and ion temperature of the deuterium-tritium fusion reactions were used as a measure of shell-gas mix, while neutron yield of the tritium-tritium fusion reaction was used as a measure of implosion performance. The results have indicated that the low-mode hydrodynamic instabilities due to surface roughness were the primary culprits for yield degradation, with atomic ablator-gas mix playing a secondary role. In addition, spherical shells with pre-imposed 2D modulations were used to measure instability growth in the acceleration phase of the implosions. The capsules were imploded using ignition-relevant laser pulses, and ablation-front modulation growth was measured using x-ray radiography for a shell convergence ratio of ?2. The measured growth was in good agreement with that predicted, thus validating simulations for the fastest growing modulations with mode numbers up to 90 in the acceleration phase. Future experiments will be focused on measurements at higher convergence, higher-mode number modulations, and growth occurring during the deceleration phase.

  2. Temperature dependent sound velocity in hydrodynamic equations for relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Mikolaj Chojnacki

    2007-09-11T23:59:59.000Z

    We analyze the effects of different forms of the sound-velocity function cs(T) on the hydrodynamic evolution of matter formed in the central region of relativistic heavy-ion collisions. At high temperatures (above the critical temperature Tc) the sound velocity is calculated from the recent lattice simulations of QCD, while in the low temperature region it is obtained from the hadron gas model. In the intermediate region we use different interpolations characterized by the values of the sound velocity at the local maximum (at T = 0.4 Tc) and local minimum (at T = Tc). In all considered cases the temperature dependent sound velocity functions yield the entropy density, which is consistent with the lattice QCD simulations at high temperature. Our calculations show that the presence of a distinct minimum of the sound velocity leads to a very long (about 20 fm/c) evolution time of the system, which is not compatible with the recent estimates based on the HBT interferometry. Hence, we conclude that the hydrodynamic description is favored in the case where the cross-over phase transition renders the smooth sound velocity function with a possible shallow minimum at Tc.

  3. Collapse dynamics of copolymers in a poor solvent: Influence of hydrodynamic interactions and chain sequence

    E-Print Network [OSTI]

    Tri Thanh Pham; Burkhard Duenweg; J. Ravi Prakash

    2010-10-29T23:59:59.000Z

    We investigate the dynamics of the collapse of a single copolymer chain, when the solvent quality is suddenly quenched from good to poor. We employ Brownian dynamics simulations of a bead-spring chain model and incorporate fluctuating hydrodynamic interactions via the Rotne-Prager-Yamakawa tensor. Various copolymer architectures are studied within the framework of a two-letter HP model, where monomers of type H (hydrophobic) attract each other, while all interactions involving P (polar or hydrophilic) monomers are purely repulsive. The hydrodynamic interactions are found to assist the collapse. Furthermore, the chain sequence has a strong influence on the kinetics and on the compactness and energy of the final state. The dynamics is typically characterised by initial rapid cluster formation, followed by coalescence and final rearrangement to form the compact globule. The coalescence stage takes most of the collapse time, and its duration is particularly sensitive to the details of the architecture. Long blocks of type P are identified as the main bottlenecks to find the globular state rapidly.

  4. Hydrodynamic Simulations of Propagating Warps and Bending Waves In Accretion Discs

    E-Print Network [OSTI]

    Richard P. Nelson; John C. B. Papaloizou

    1999-07-06T23:59:59.000Z

    We present the results of a study of propagating warp or bending waves in accretion discs. Three dimensional hydrodynamic simulations were performed using SPH, and the results of these are compared with calculations based on the linear theory of warped discs. We consider primarily the physical regime in which the dimensionless viscosity parameter `alpha' disc aspect ratio, so that bending waves are expected to propagate. We also present calculations in which `alpha' > H/r, where the warps are expected to behave diffusively. Small amplitude perturbations are studied in both Keplerian and slightly non Keplerian discs, and we find that the SPH results can be reasonably well fitted by those of the linear theory. The main results of these calculations are: (1) the warp in Keplerian discs when `alpha' H/r, (3) the non Keplerian discs exhibit a substantially more dispersive behaviour of the warps. Initially imposed higher amplitude nonlinear warping disturbances were studied in Keplerian discs. The results indicate that nonlinear warps can lead to the formation of shocks, and that the evolution of the warp becomes less wave-like and more diffusive in character. This work is relevant to the study of the warped accretion discs that may occur around Kerr black holes or in misaligned binary systems. The results indicate that SPH can accurately model the hydrodynamics of warped discs, even when using rather modest numbers of particles.

  5. Microgrid Testing

    SciTech Connect (OSTI)

    Shirazi, M.; Kroposki, B.

    2012-01-01T23:59:59.000Z

    With the publication of IEEE 1574.4 Guide for Design, Operation, and Integration of Distributed Resource Island Systems with Electric Power Systems, there is an increasing amount of attention on not only the design and operations of microgrids, but also on the proper operation and testing of these systems. This standard provides alternative approaches and good practices for the design, operation, and integration of microgrids. This includes the ability to separate from and reconnect to part of the utility grid while providing power to the islanded power system. This presentation addresses the industry need to develop standardized testing and evaluation procedures for microgrids in order to assure quality operation in the grid connected and islanded modes of operation.

  6. Assessment of Energy Removal Impacts on Physical Systems: Hydrodynamic Model Domain Expansion and Refinement, and Online Dissemination of Model Results

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Khangaonkar, Tarang; Wang, Taiping

    2010-08-01T23:59:59.000Z

    In this report we describe the 1) the expansion of the PNNL hydrodynamic model domain to include the continental shelf along the coasts of Washington, Oregon, and Vancouver Island; and 2) the approach and progress in developing the online/Internet disseminations of model results and outreach efforts in support of the Puget Sound Operational Forecast System (PS-OPF). Submittal of this report completes the work on Task 2.1.2, Effects of Physical Systems, Subtask 2.1.2.1, Hydrodynamics, for fiscal year 2010 of the Environmental Effects of Marine and Hydrokinetic Energy project.

  7. Hydrodynamic forces due to waves and a current induced on a pipeline placed in an open trench 

    E-Print Network [OSTI]

    Lee, Jaeyoung

    1991-01-01T23:59:59.000Z

    HYDRODYNAMIC FORCES DUE TO WAVES AND A CURRENT INDUCED ON A PIPELINE PLACED IN AN OPEN TRENCH A Thesis by JAEYOUNG LEE Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE December 1991 Major Subject: Ocean Engineering HYDRODYNAMIC FORCES DUE TO WAVES AND A CURRENT INDUCED ON A PIPELINE PLACED IN AN OPEN TRENCH A Thesis by JAEYOUNG LEE Approved as to style and content by: John B...

  8. Rapid embedded wire heating via resistive guiding of laser-generated fast electrons as a hydrodynamic driver

    SciTech Connect (OSTI)

    Robinson, A. P. L.; Schmitz, H. [Central Laser Facility, STFC Rutherford-Appleton Laboratory, Didcot OX11 0QX (United Kingdom)] [Central Laser Facility, STFC Rutherford-Appleton Laboratory, Didcot OX11 0QX (United Kingdom); Pasley, J. [Central Laser Facility, STFC Rutherford-Appleton Laboratory, Didcot OX11 0QX (United Kingdom) [Central Laser Facility, STFC Rutherford-Appleton Laboratory, Didcot OX11 0QX (United Kingdom); York Plasma Institute, University of York, York YO10 5DD (United Kingdom)

    2013-12-15T23:59:59.000Z

    Resistively guiding laser-generated fast electron beams in targets consisting of a resistive wire embedded in lower Z material should allow one to rapidly heat the wire to over 100 eV over a substantial distance without strongly heating the surrounding material. On the multi-ps timescale, this can drive hydrodynamic motion in the surrounding material. Thus, ultra-intense laser solid interactions have the potential as a controlled driver of radiation hydrodynamics in solid density material. In this paper, we assess the laser and target parameters needed to achieve such rapid and controlled heating of the embedded wire.

  9. M. Steffen et al.: Hydrodynamical Models of Circumstellar Dust Shells 5 Figure 3. Top: Time sequence of spectral energy distributions computed from our oxygen

    E-Print Network [OSTI]

    sequence of spectral energy distributions computed from our oxygen star model with a dust shell composed.: Hydrodynamical Models of Circumstellar Dust Shells Figure 2. Top: Time sequence of spectral energy distributionsM. Steffen et al.: Hydrodynamical Models of Circumstellar Dust Shells 5 Figure 3. Top: Time

  10. Collective flow in event-by-event transport plus hydrodynamics hybrid approach

    E-Print Network [OSTI]

    Rajeev S. Bhalerao; Amaresh Jaiswal; Subrata Pal

    2015-03-03T23:59:59.000Z

    Complete evolution of the strongly interacting matter formed in ultra-relativistic heavy-ion collisions is studied within a coupled Boltzmann and relativistic viscous hydrodynamics approach. For the initial non-equilibrium evolution phase, we employ the AMPT model that explicitly includes event-by-event fluctuations in the number and positions of the participating nucleons as well as of the produced partons with subsequent parton transport. The ensuing near-equilibrium evolution of quark-gluon and hadronic matter is modeled within the 2+1D relativistic viscous hydrodynamics. We probe the role of parton dynamics in generating and maintaining the spatial anisotropy in the pre-equilibrium phase. Substantial eccentricities epsilon_n are found to be generated in the event-by-event fluctuations in parton production from initial nucleon-nucleon collisions. For ultra-central heavy-ion collisions, the model is able to explain qualitatively the unexpected hierarchy of the harmonic flow coefficients v_n(pT) (n=2-6) observed at the LHC energy. We find that the results for v_n(pT) are rather insensitive to the variation (within a range) of the time of switchover from AMPT parton transport to hydrodynamic evolution. The usual Grad and the recently proposed Chapman-Enskog-like (non-equilibrium) single-particle distribution functions are found to give very similar results for v_n (n=2-4). The model describes well both the RHIC and LHC data for v_n(pT) at various centralities, with a constant shear viscosity to entropy density ratio 0.08 and 0.12, respectively. The event-by-event distributions of v_{2,3} are in good agreement with the LHC data for mid-central collisions. The linear response relation v_n = k_n*epsilon_n is found to be true for n=2,3, except at large values of epsilon_n, where a larger value of k_n is required, suggesting a small admixture of positive nonlinear response even for n=2,3.

  11. Modifications of Carbonate Fracture Hydrodynamic Properties by CO{sub 2}-Acidified Brine Flow

    SciTech Connect (OSTI)

    Deng, Hang; Ellis, Brian R.; Peters, Catherine A.; Fitts, Jeffrey P.; Crandall, Dustin; Bromhal, Grant S.

    2013-08-01T23:59:59.000Z

    Acidic reactive flow in fractures is relevant in subsurface activities such as CO{sub 2} geological storage and hydraulic fracturing. Understanding reaction-induced changes in fracture hydrodynamic properties is essential for predicting subsurface flows such as leakage, injectability, and fluid production. In this study, x-ray computed tomography scans of a fractured carbonate caprock were used to create three dimensional reconstructions of the fracture before and after reaction with CO{sub 2}-acidified brine (Ellis et al., 2011, Greenhouse Gases: Sci. Technol., 1:248-260). As expected, mechanical apertures were found to increase substantially, doubling and even tripling in some places. However, the surface geometry evolved in complex ways including ‘comb-tooth’ structures created from preferential dissolution of calcite in transverse sedimentary bands, and the creation of degraded zones, i.e. porous calcite-depleted areas on reacted fracture surfaces. These geometric alterations resulted in increased fracture roughness, as measured by surface Z{sub 2} parameters and fractal dimensions D{sub f}. Computational fluid dynamics (CFD) simulations were conducted to quantify the changes in hydraulic aperture, fracture transmissivity and permeability. The results show that the effective hydraulic apertures are smaller than the mechanical apertures, and the changes in hydraulic apertures are nonlinear. Overestimation of flow rate by a factor of two or more would be introduced if fracture hydrodynamic properties were based on mechanical apertures, or if hydraulic aperture is assumed to change proportionally with mechanical aperture. The differences can be attributed, in part, to the increase in roughness after reaction, and is likely affected by contiguous transverse sedimentary features. Hydraulic apertures estimated by the 1D statistical model and 2D local cubic law (LCL) model are consistently larger than those calculated from the CFD simulations. In addition, a novel ternary segmentation method was devised to handle the degraded zones, allowing for a bounding analysis of the effects on hydraulic properties. We found that the degraded zones account for less than 15% of the fracture volume, but cover 70% to 80% of the fracture surface. When the degraded zones are treated as part of the fracture, the fracture transmissivities are two to four times larger because the fracture surfaces after reaction are not as rough as they would be if one considers the degraded zone as part of the rock. Therefore, while degraded zones created during geochemical reactions may not significantly increase mechanical aperture, this type of feature cannot be ignored and should be treated with prudence when predicting fracture hydrodynamic properties.

  12. Prototype to Test WHY prototype to test

    E-Print Network [OSTI]

    Prinz, Friedrich B.

    Prototype to Test METHOD WHY prototype to test HOW to prototype to test Prototyping to test or design space. The fundamental way you test your prototypes is by letting users experience them and react to them. In creating prototypes to test with users you have the opportunity to examine your solution

  13. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 258164-173 (1991) Hydrodynamics of the Feet of Fish-Catching Bats

    E-Print Network [OSTI]

    Fish, Frank

    1991-01-01T23:59:59.000Z

    THE JOURNAL OF EXPERIMENTAL ZOOLOGY 258164-173 (1991) Hydrodynamics of the Feet of Fish-Catching Bats: Influence of the Water Surface on Drag and Morphological Design FRANK E. FISH, BRAD R. BLOOD and Pizonyx uiuesi, display similar hind foot mor- phologies specialized for their fish-catching habits

  14. Application of Non-local Quantum Hydrodynamics to the Description of the Charged Density Waves in the Graphen Crystal Lattice

    E-Print Network [OSTI]

    Boris V. Alexeev; Irina V. Ovchinnikova

    2012-11-24T23:59:59.000Z

    The motion of the charged particles in graphen in the frame of the quantum non-local hydrodynamic description is considered. It is shown as results of the mathematical modeling that the mentioned motion is realizing in the soliton forms. The dependence of the size and structure of solitons on the different physical parameters is investigated.

  15. Use of remote sensing data to enhance the performance of a hydrodynamic simulation of a partially frozen power plant

    E-Print Network [OSTI]

    Salvaggio, Carl

    , USA b Savannah River National Laboratory, Aiken, South Carolina, USA c Rochester Institute. INTRODUCTION The ALGE code is a hydrodynamic model developed by Savannah River National Laboratory (SRNL of Technology, Center for Imaging Science, Digital Imaging and Remote Sensing Laboratory, Rochester, New York

  16. Two-dimensional segmentation of small convective patterns in radiation hydrodynamics simulations

    E-Print Network [OSTI]

    Lemmerer, B; Hanslmeier, A; Veronig, A; Thonhofer, S; Grimm-Strele, H; Kariyappa, R

    2015-01-01T23:59:59.000Z

    Recent results from high-resolution solar granulation observations indicate the existence of a population of small granular cells that are smaller than 600 km in diameter. These small convective cells strongly contribute to the total area of granules and are located in the intergranular lanes, where they form clusters and chains. We study high-resolution radiation hydrodynamics simulations of the upper convection zone and photosphere to detect small granular cells, define their spatial alignment, and analyze their physical properties. We developed an automated image-segmentation algorithm specifically adapted to high-resolution simulations to identify granules. The resulting segmentation masks were applied to physical quantities, such as intensity and vertical velocity profiles, provided by the simulation. A new clustering algorithm was developed to study the alignment of small granular cells. This study shows that small granules make a distinct contribution to the total area of granules and form clusters of ...

  17. Prediction of hydrodynamic forces on oscillating bodies by unsteady turbulent wake theory

    SciTech Connect (OSTI)

    Matsumoto, Koichiro [NKK Corp., Tsu (Japan)

    1994-12-31T23:59:59.000Z

    In the paper presented at ISOPE-91, Edinburgh the author introduced a new practical theory to predict hydrodynamic forces acting on arbitrarily oscillating bodies. The theory is based on the assumption that the Morison`s equation can be applied with constant drag and mass coefficients provided that wake velocities produced by the body motions in all past history are properly corrected for. The induced wake velocity is calculated by the unsteady turbulent wake theory. In the present paper this new theory is applied to practical body oscillation problems such as the irregular oscillation of a cylinder, an oscillating cylinder in steady current, and the elliptic or circular oscillation of a cylinder. Some of the theoretical calculation results are compared with experiments, and the applicability of the theory is discussed.

  18. From AdS/CFT correspondence to hydrodynamics. II. Sound waves

    E-Print Network [OSTI]

    G. Policastro; D. T. Son; A. O. Starinets

    2005-07-26T23:59:59.000Z

    As a non-trivial check of the non-supersymmetric gauge/gravity duality, we use a near-extremal black brane background to compute the retarded Green's functions of the stress-energy tensor in N=4 super-Yang-Mills (SYM) theory at finite temperature. For the long-distance, low-frequency modes of the diagonal components of the stress-energy tensor, hydrodynamics predicts the existence of a pole in the correlators corresponding to propagation of sound waves in the N=4 SYM plasma. The retarded Green's functions obtained from gravity do indeed exhibit this pole, with the correct values for the sound speed and the rate of attenuation.

  19. Hydrodynamics in bridging and aggregation of two colloidal particles in a near-critical binary mixture

    E-Print Network [OSTI]

    Shunsuke Yabunaka; Ryuichi Okamoto; Akira Onuki

    2015-05-23T23:59:59.000Z

    We investigate bridging and aggregation of two colloidal particles in a near-critical binary mixture when the fluid far from the particles is outside the coexistence (CX) curve and is rich in the component disfavored by the colloid surfaces. In such situations, the adsorption-induced interaction is enhanced, leading to bridging and aggregation of the particles. We realize bridging firstly by changing the temperature with a fixed interparticle separation and secondly by letting the two particles aggregate. The interparticle attractive force dramatically increases upon bridging. The dynamics is governed by hydrodynamic flow around the colloid surfaces. In aggregation, the adsorption layers move with the particles and squeezing occurs at narrow separation. We take into account the renormalization effect due to the critical fluctuations using the recent local functional theory [J. Chem. Phys. 136, 114704 (2012)].

  20. Analytical and numerical Gubser solutions of the second-order hydrodynamics

    E-Print Network [OSTI]

    Long-Gang Pang; Yoshitaka Hatta; Xin-Nian Wang; Bo-Wen Xiao

    2014-12-10T23:59:59.000Z

    Evolution of quark-gluon plasma (QGP) near equilibrium can be described by the second-order relativistic viscous hydrodynamic equations. Consistent and analytically verifiable numerical solutions are critical for phenomenological studies of the collective behavior of QGP in high-energy heavy-ion collisions. A novel analytical solution based on the conformal Gubser flow which is a boost-invariant solution with transverse fluid velocity is presented. It is used to verify with high precision the numerical solution with a newly developed $(3+1)$-dimensional second-order viscous hydro code (CLVisc). The perfect agreement between the analytical and numerical solutions demonstrates the reliability of the numerical simulations with the second-order viscous corrections. This lays the foundation for future phenomenological studies that allow one to gain access to the second-order transport coefficients.

  1. Hydrodynamic effects of eroded materials on response of plasma-facing component during a tokamak disruption

    SciTech Connect (OSTI)

    Hassanein, A.; Konkashbaev, I.

    1999-10-25T23:59:59.000Z

    Loss of plasma confinement causes surface and structural damage to plasma-facing materials (PFMs) and remains a major obstacle for tokamak reactors. The deposited plasma energy results in surface erosion and structural failure. The surface erosion consists of vaporization, spallation, and liquid splatter of metallic materials, while the structural damage includes large temperature increases in structural materials and at the interfaces between surface coatings and structural members. Comprehensive models (contained in the HEIGHTS computer simulation package) are being used self-consistently to evaluate material damage. Splashing mechanisms occur as a result of volume bubble boiling and liquid hydrodynamic instabilities and brittle destruction mechanisms of nonmelting materials. The effect of macroscopic erosion on total mass losses and lifetime is evaluated. The macroscopic erosion products may further protect PFMs from severe erosion (via the droplet-shielding effect) in a manner similar to that of the vapor shielding concept.

  2. Development of a Hydrodynamic and Transport model of Bellingham Bay in Support of Nearshore Habitat Restoration

    SciTech Connect (OSTI)

    Wang, Taiping; Yang, Zhaoqing; Khangaonkar, Tarang

    2010-04-22T23:59:59.000Z

    In this study, a hydrodynamic model based on the unstructured-grid finite volume coastal ocean model (FVCOM) was developed for Bellingham Bay, Washington. The model simulates water surface elevation, velocity, temperature, and salinity in a three-dimensional domain that covers the entire Bellingham Bay and adjacent water bodies, including Lummi Bay, Samish Bay, Padilla Bay, and Rosario Strait. The model was developed using Pacific Northwest National Laboratory’s high-resolution Puget Sound and Northwest Straits circulation and transport model. A sub-model grid for Bellingham Bay and adjacent coastal waters was extracted from the Puget Sound model and refined in Bellingham Bay using bathymetric light detection and ranging (LIDAR) and river channel cross-section data. The model uses tides, river inflows, and meteorological inputs to predict water surface elevations, currents, salinity, and temperature. A tidal open boundary condition was specified using standard National Oceanic and Atmospheric Administration (NOAA) predictions. Temperature and salinity open boundary conditions were specified based on observed data. Meteorological forcing (wind, solar radiation, and net surface heat flux) was obtained from NOAA real observations and National Center for Environmental Prediction North American Regional Analysis outputs. The model was run in parallel with 48 cores using a time step of 2.5 seconds. It took 18 hours of cpu time to complete 26 days of simulation. The model was calibrated with oceanographic field data for the period of 6/1/2009 to 6/26/2009. These data were collected specifically for the purpose of model development and calibration. They include time series of water-surface elevation, currents, temperature, and salinity as well as temperature and salinity profiles during instrument deployment and retrieval. Comparisons between model predictions and field observations show an overall reasonable agreement in both temporal and spatial scales. Comparisons of root mean square error values for surface elevation, velocity, temperature, and salinity time series are 0.11 m, 0.10 m/s, 1.28oC, and 1.91 ppt, respectively. The model was able to reproduce the salinity and temperature stratifications inside Bellingham Bay. Wetting and drying processes in tidal flats in Bellingham Bay, Samish Bay, and Padilla Bay were also successfully simulated. Both model results and observed data indicated that water surface elevations inside Bellingham Bay are highly correlated to tides. Circulation inside the bay is weak and complex and is affected by various forcing mechanisms, including tides, winds, freshwater inflows, and other local forcing factors. The Bellingham Bay model solution was successfully linked to the NOAA oil spill trajectory simulation model “General NOAA Operational Modeling Environment (GNOME).” Overall, the Bellingham Bay model has been calibrated reasonably well and can be used to provide detailed hydrodynamic information in the bay and adjacent water bodies. While there is room for further improvement with more available data, the calibrated hydrodynamic model provides useful hydrodynamic information in Bellingham Bay and can be used to support sediment transport and water quality modeling as well as assist in the design of nearshore restoration scenarios.

  3. Investigating puzzling aspects of the quantum theory by means of its hydrodynamic formulation

    E-Print Network [OSTI]

    Sanz, A S

    2015-01-01T23:59:59.000Z

    Bohmian mechanics, a hydrodynamic formulation of the quantum theory, constitutes a useful resource to analyze the role of the phase as the mechanism responsible for the dynamical evolution of quantum systems. Here this role is discussed in the context of quantum interference. Specifically, it is shown that when dealing with two wave-packet coherent superpositions this phenomenon is analogous to an effective collision of a single wave packet with a barrier. This effect is illustrated by means of a numerical simulation of Young's two-slit experiment. Furthermore, outcomes from this analysis are also applied to a realistic simulation of Wheeler's delayed choice experiment. As it is shown, in both cases the Bohmian formulation helps to understand in a natural way (and, therefore, to demystify) what are typically regarded as paradoxical aspects of the quantum theory, simply stressing the important dynamical role played by the quantum phase. Accordingly, our conception of quantum systems should not rely on artifici...

  4. PROBING NEAR-SURFACE ATMOSPHERIC TURBULENCE WITH LIDAR MEASUREMENTS AND HIGH-RESOLUTION HYDRODYNAMIC MODELS

    SciTech Connect (OSTI)

    J. KAO; D. COOPER; ET AL

    2000-11-01T23:59:59.000Z

    As lidar technology is able to provide fast data collection at a resolution of meters in an atmospheric volume, it is imperative to promote a modeling counterpart of the lidar capability. This paper describes an integrated capability based on data from a scanning water vapor lidar and a high-resolution hydrodynamic model (HIGRAD) equipped with a visualization routine (VIEWER) that simulates the lidar scanning. The purpose is to better understand the spatial and temporal representativeness of the lidar measurements and, in turn, to extend their utility in studying turbulence fields in the atmospheric boundary layer. Raman lidar water vapor data collected over the Pacific warm pool and the simulations with the HIGRAD code are used for identifying the underlying physics and potential aliasing effects of spatially resolved lidar measurements. This capability also helps improve the trade-off between spatial-temporal resolution and coverage of the lidar measurements.

  5. Scaling theory for hydrodynamic lubrication, with application to non-Newtonian lubricants

    E-Print Network [OSTI]

    Patrick B. Warren

    2015-02-04T23:59:59.000Z

    Scaling arguments are developed for the load balance in hydrodynamic lubrication, and applied to non-Newtonian lubricants with a shear-thinning rheology typical of a structured liquid. It is argued that the shear thinning regime may be mechanically unstable in lubrication flow, and consequently the Stribeck (friction) curve should be discontinuous, with possible hysteresis. Further analysis suggests that normal stress and flow transience (stress overshoot) do not destroy this basic picture, although they may provide stabilising mechanisms at higher shear rates. Extensional viscosity is also expected to be insignificant unless the Trouton ratio is large. A possible application to recent theories of shear thickening in non-Brownian particulate suspensions is indicated.

  6. Hydrodynamical adaptive mesh refinement simulations of turbulent flows - I. Substructure in a wind

    E-Print Network [OSTI]

    Iapichino, L; Schmidt, W; Niemeyer, J C

    2008-01-01T23:59:59.000Z

    The problem of the resolution of turbulent flows in adaptive mesh refinement (AMR) simulations is investigated by means of 3D hydrodynamical simulations in an idealised setup, representing a moving subcluster during a merger event. AMR simulations performed with the usual refinement criteria based on local gradients of selected variables do not properly resolve the production of turbulence downstream of the cluster. Therefore we apply novel AMR criteria which are optimised to follow the evolution of a turbulent flow. We demonstrate that these criteria provide a better resolution of the flow past the subcluster, allowing us to follow the onset of the shear instability, the evolution of the turbulent wake and the subsequent back-reaction on the subcluster core morphology. We discuss some implications for the modelling of cluster cold fronts.

  7. Hydrodynamical adaptive mesh refinement simulations of turbulent flows - I. Substructure in a wind

    E-Print Network [OSTI]

    L. Iapichino; J. Adamek; W. Schmidt; J. C. Niemeyer

    2008-07-01T23:59:59.000Z

    The problem of the resolution of turbulent flows in adaptive mesh refinement (AMR) simulations is investigated by means of 3D hydrodynamical simulations in an idealised setup, representing a moving subcluster during a merger event. AMR simulations performed with the usual refinement criteria based on local gradients of selected variables do not properly resolve the production of turbulence downstream of the cluster. Therefore we apply novel AMR criteria which are optimised to follow the evolution of a turbulent flow. We demonstrate that these criteria provide a better resolution of the flow past the subcluster, allowing us to follow the onset of the shear instability, the evolution of the turbulent wake and the subsequent back-reaction on the subcluster core morphology. We discuss some implications for the modelling of cluster cold fronts.

  8. Radiative hydrodynamics in the highly super adiabatic layer of stellar evolution models

    E-Print Network [OSTI]

    F. J. Robinson; P. Demarque; S. Sofia; K. L. Chan; Y. -C. Kim; D. B. Guenther

    2000-11-02T23:59:59.000Z

    We present results of three dimensional simulations of the uppermost part of the sun, at 3 stages of its evolution. Each model includes physically realistic radiative-hydrodynamics (the Eddington approximation is used in the optically thin region), varying opacities and a realistic equation of state (full treatment of the ionization of H and He). In each evolution model, we investigate a domain, which starts at the top of the photosphere and ends just inside the convection zone (about 2400 km in the sun model). This includes all of the super-adiabatic layer (SAL). Due to the different positions of the three models in the $log (g) $ vs $log T_{eff}$ plane, the more evolved models have lower density atmospheres. The reduction in density causes the amount of overshoot into the radiation layer, to be greater in the more evolved models.

  9. Predictions for {radical} (s) =200A; GeV Au+Au collisions from relativistic hydrodynamics

    SciTech Connect (OSTI)

    Schlei, B.R. [Physics Division, P-25, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Physics Division, P-25, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Schlei, B.R.; Strottman, D. [Theoretical Division, DDT-DO, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division, DDT-DO, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    1999-01-01T23:59:59.000Z

    The relativistic hydrodynamical model HYLANDER-C is used to give estimates for single inclusive particle momentum spectra in {radical} (s) =200 GeV/nucleon Au+Au collisions that will be investigated experimentally in the near future. The predictions are based on initial conditions that the initial fireball has a longitudinal extension of 1.6 fm and an initial energy density of 30.8 GeV/fm{sup 3} as obtained from a cascade model. For the collision energy considered here, different stopping scenarios are explored for the first time. Our calculations give particle yields of the order of 10thinsp000 to 20thinsp000 charged particles per event. {copyright} {ital 1999} {ital The American Physical Society}

  10. Single-particle spectral density of a Bose gas in the two-fluid hydrodynamic regime

    SciTech Connect (OSTI)

    Arahata, Emiko; Nikuni, Tetsuro; Griffin, Allan [Department of Physics, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601 (Japan); Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7 (Canada)

    2011-11-15T23:59:59.000Z

    In Bose superfluids, the single-particle Green's function can be directly related to the superfluid velocity-velocity correlation function in the hydrodynamic regime. An explicit expression for the single-particle spectral density was originally written down by Hohenberg and Martin in 1965, starting from the two-fluid equations for a superfluid. We give a simple derivation of their results. Using these results, we calculate the relative weights of first and second sound modes in the single-particle spectral density as a function of temperature in a uniform Bose gas. We show that the second sound mode makes a dominant contribution to the single-particle spectrum in a relatively high-temperature region. We also discuss the possibility of experimental observation of the second sound mode in a Bose gas by photoemission spectroscopy.

  11. Investigating the Magnetorotational Instability with Dedalus, and Open-Souce Hydrodynamics Code

    SciTech Connect (OSTI)

    Burns, Keaton J; /UC, Berkeley, aff SLAC

    2012-08-31T23:59:59.000Z

    The magnetorotational instability is a fluid instability that causes the onset of turbulence in discs with poloidal magnetic fields. It is believed to be an important mechanism in the physics of accretion discs, namely in its ability to transport angular momentum outward. A similar instability arising in systems with a helical magnetic field may be easier to produce in laboratory experiments using liquid sodium, but the applicability of this phenomenon to astrophysical discs is unclear. To explore and compare the properties of these standard and helical magnetorotational instabilities (MRI and HRMI, respectively), magnetohydrodynamic (MHD) capabilities were added to Dedalus, an open-source hydrodynamics simulator. Dedalus is a Python-based pseudospectral code that uses external libraries and parallelization with the goal of achieving speeds competitive with codes implemented in lower-level languages. This paper will outline the MHD equations as implemented in Dedalus, the steps taken to improve the performance of the code, and the status of MRI investigations using Dedalus.

  12. Causal dissipative hydrodynamics for QGP fluid in 2+1 dimensions

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2007-08-01T23:59:59.000Z

    In 2nd order causal dissipative theory, space-time evolution of QGP fluid is studied in 2+1 dimensions. Relaxation equations for shear stress tensors are solved simultaneously with the energy-momentum conservation equations. Comparison of evolution of ideal and viscous QGP fluid, initialized under the same conditions, e.g. same equilibration time, energy density and velocity profile, indicate that in a viscous dynamics, energy density or temperature of the fluid evolve slowly, than in an ideal fluid. Cooling gets slower as viscosity increases. Transverse expansion also increases in a viscous dynamics. For the first time we have also studied elliptic flow of 'quarks' in causal viscous dynamics. It is shown that elliptic flow of quarks saturates due to non-equilibrium correction to equilibrium distribution function, and can not be mimicked by an ideal hydrodynamics.

  13. Viscous hydrodynamics description of $?$ meson production in Au+Au and Cu+Cu collisions

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2009-01-27T23:59:59.000Z

    In the Israel-Stewart's theory of 2nd order dissipative hydrodynamics, we have simulated $\\phi$ production in Au+Au and Cu+Cu collisions at $\\sqrt{s}_{NN}$=200 GeV. Evolution of QGP fluid with viscosity over the entropy ratio $\\eta/s$=0.25, thermalised at $\\tau_i$=0.2 fm, with initial energy density $\\epsilon_i$=5.1 $GeV/fm^3$ explains the experimental data on $\\phi$ multiplicity, integrated $v_2$, mean $p_T$, $p_T$ spectra and elliptic flow in central and mid-central Au+Au collisions. $\\eta/s$=0.25 is also consistent with centrality dependence of $\\phi$ $p_T$ spectra in Cu+Cu collisions. The central energy density in Cu+Cu collisions is $\\epsilon_i$=3.48 $GeV/fm^3$.

  14. Hydrodynamic Scaling Analysis of Nuclear Fusion driven by ultra-intense laser-plasma interactions

    E-Print Network [OSTI]

    Sachie Kimura; Aldo Bonasera

    2012-07-24T23:59:59.000Z

    We discuss scaling laws of fusion yields generated by laser-plasma interactions. The yields are found to scale as a function of the laser power. The origin of the scaling law in the laser driven fusion yield is derived in terms of hydrodynamic scaling. We point out that the scaling properties can be attributed to the laser power dependence of three terms: the reaction rate, the density of the plasma and the projected range of the plasma particle in the target medium. The resulting scaling relations have a predictive power that enables estimating the fusion yield for a nuclear reaction which has not been investigated by means of the laser accelerated ion beams.

  15. Note on specific chiral ensembles of statistical hydrodynamics: "order function" for transition of turbulence transfer scenarios

    E-Print Network [OSTI]

    Jian-Zhou Zhu

    2014-07-31T23:59:59.000Z

    Hydrodynamic helicity signatures the parity symmetry breaking, chirality, of the flow. Statistical hydrodynamics thus respect chirality, as symmetry breaking and restoration are key to their fundamentals, such as the spectral transfer direction and its mechanism. Homochiral sub-system of three-dimensional (3D) Navier-Stokes isotropic turbulence has been numerically realized with helical representation technique to present inverse energy cascade [Biferale et al., Phys. Rev. Lett., {\\bf 108}, 164501 (2012)]. The situation is analogous to 2D turbulence where inverse energy cascade, or more generally energy-enstrophy dual cascade scenario, was argued with the help of a negative temperature state of the absolute equilibrium by Kraichnan. Indeed, if the helicity in such a system is taken to be positive without loss of generality, a corresponding negative temperature state can be identified [Zhu et al., J. Fluid Mech., {\\bf 739}, 479 (2014)]. Here, for some specific chiral ensembles of turbulence, we show with the corresponding absolute equilibria that even if the helicity distribution over wavenumbers is sign definite, different \\textit{ansatzes} of the shape function, defined by the ratio between the specific helicity and energy spectra $s(k)=H(k)/E(k)$, imply distinct transfer directions, and we could have inverse-helicity and forward-energy dual transfers (with, say, $s(k)\\propto k^{-2}$ resulting in absolute equilibrium modal spectral density of energy $U(k)=\\frac{1}{\\alpha +\\beta k^{-2}}$, exactly the enstrophy one of two-dimensional Euler by Kraichan), simultaneous forward transfers (with $s(k)=constant$), or even no simply-directed transfer (with, say, non-monotonic $s(k) \\propto \\sin^2k$), besides the inverse-energy and forward-helicity dual transfers (with, say, $s(k)=k$ as in the homochiral case).

  16. Effect of the Coriolis Force on the Hydrodynamics of Colliding Wind Binaries

    E-Print Network [OSTI]

    M. Nicole Lemaster; James M. Stone; Thomas A. Gardiner

    2007-02-16T23:59:59.000Z

    Using fully three-dimensional hydrodynamic simulations, we investigate the effect of the Coriolis force on the hydrodynamic and observable properties of colliding wind binary systems. To make the calculations tractable, we assume adiabatic, constant velocity winds. The neglect of radiative driving, gravitational deceleration, and cooling limit the application of our models to real systems. However, these assumptions allow us to isolate the effect of the Coriolis force, and by simplifying the calculations, allow us to use a higher resolution (up to 640^3) and to conduct a larger survey of parameter space. We study the dynamics of collidng winds with equal mass loss rates and velocities emanating from equal mass stars on circular orbits, with a range of values for the ratio of the wind to orbital velocity. We also study the dynamics of winds from stars on elliptical orbits and with unequal strength winds. Orbital motion of the stars sweeps the shocked wind gas into an Archimedean spiral, with asymmetric shock strengths and therefore unequal postshock temperatures and densities in the leading and trailing edges of the spiral. We observe the Kelvin-Helmholtz instability at the contact surface between the shocked winds in systems with orbital motion even when the winds are identical. The change in shock strengths caused by orbital motion increases the volume of X-ray emitting post-shock gas with T > 0.59 keV by 63% for a typical system as the ratio of wind velocity to orbital velocity decreases to V_w/V_o = 2.5. This causes increased free-free emission from systems with shorter orbital periods and an altered time-dependence of the wind attenuation. We comment on the importance of the effects of orbital motion on the observable properties of colliding wind binaries.

  17. Formation of Nuclear Disks and Supermassive Black Hole Binaries in Multi-Scale Hydrodynamical Galaxy Mergers

    E-Print Network [OSTI]

    Lucio Mayer; Stelios Kazantzidis; Andres Escala

    2008-07-22T23:59:59.000Z

    (Abridged) We review the results of the first multi-scale, hydrodynamical simulations of mergers between galaxies with central supermassive black holes (SMBHs) to investigate the formation of SMBH binaries in galactic nuclei. We demonstrate that strong gas inflows produce nuclear disks at the centers of merger remnants whose properties depend sensitively on the details of gas thermodynamics. In numerical simulations with parsec-scale spatial resolution in the gas component and an effective equation of state appropriate for a starburst galaxy, we show that a SMBH binary forms very rapidly, less than a million years after the merger of the two galaxies. Binary formation is significantly suppressed in the presence of a strong heating source such as radiative feedback by the accreting SMBHs. We also present preliminary results of numerical simulations with ultra-high spatial resolution of 0.1 pc in the gas component. These simulations resolve the internal structure of the resulting nuclear disk down to parsec scales and demonstrate the formation of a central massive object (~ 10^8 Mo) by efficient angular momentum transport. This is the first time that a radial gas inflow is shown to extend to parsec scales as a result of the dynamics and hydrodynamics involved in a galaxy merger, and has important implications for the fueling of SMBHs. Due to the rapid formation of the central clump, the density of the nuclear disk decreases significantly in its outer region, reducing dramatically the effect of dynamical friction and leading to the stalling of the two SMBHs at a separation of ~1 pc. We discuss how the orbital decay of the black holes might continue in a more realistic model which incorporates star formation and the multi-phase nature of the ISM.

  18. MECHANICAL TEST LAB CAPABILITIES

    E-Print Network [OSTI]

    MECHANICAL TEST LAB CAPABILITIES · Static and cyclic testing (ASTM and non-standard) · Impact drop testing · Slow-cycle fatigue testing · High temperature testing to 2500°F · ASTM/ Boeing/ SACMA standard testing · Ability to design and fabricate non-standard test fixtures and perform non-standard tests

  19. Orion Flight Test Exploration Flight Test-1

    E-Print Network [OSTI]

    Waliser, Duane E.

    Orion Flight Test Exploration Flight Test-1 PRESS KIT/December 2014 www.nasa.gov NP-2014-11-020-JSC National Aeronautics and Space Administration #12;#12;Orion Flight Test December 2014 Contents Section Page ........................................................................................... 28 i #12;Orion Flight Test ii December 2014 #12;Orion Flight Test December 2014 Flight Overview

  20. Test Preparation Options Free Test Prep Websites

    E-Print Network [OSTI]

    Stowell, Michael

    Test Preparation Options Free Test Prep Websites ACT: http: http://www.collegeboard.com/student/testing/sat/prep_one/test.html http://www.number2.com://testprep.princetonreview.com/CourseSearch/Search.aspx?itemCode=17&productType=F&rid=1&zip=803 02 Test Prep Classes Front Range Community College: Classes

  1. Test and Test Equipment Joshua Lottich

    E-Print Network [OSTI]

    Patel, Chintan

    Test and Test Equipment Joshua Lottich CMPE 640 11/23/05 #12;Testing Verifies that manufactured chip meets design specifications. Cannot test for every potential defect. Modeling defects as faults allows for passing and failing of chips. Ideal test would capture all defects and pass only chips

  2. EVOLUTION AND HYDRODYNAMICS OF THE VERY BROAD X-RAY LINE EMISSION IN SN 1987A

    SciTech Connect (OSTI)

    Dewey, D.; Canizares, C. R. [MIT Kavli Institute, Cambridge, MA 02139 (United States); Dwarkadas, V. V. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Haberl, F.; Sturm, R., E-mail: dd@space.mit.edu, E-mail: vikram@oddjob.uchicago.edu [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, Garching D-85748 (Germany)

    2012-06-20T23:59:59.000Z

    Observations of SN 1987A by the Chandra High Energy Transmission Grating (HETG) in 1999 and the XMM-Newton Reflection Grating Spectrometer (RGS) in 2003 show very broad (v-b) lines with a full width at half-maximum (FWHM) of order 10{sup 4} km s{sup -1}; at these times the blast wave (BW) was primarily interacting with the H II region around the progenitor. Since then, the X-ray emission has been increasingly dominated by narrower components as the BW encounters dense equatorial ring (ER) material. Even so, continuing v-b emission is seen in the grating spectra suggesting that the interaction with H II region material is ongoing. Based on the deep HETG 2007 and 2011 data sets, and confirmed by RGS and other HETG observations, the v-b component has a width of 9300 {+-} 2000 km s{sup -1} FWHM and contributes of order 20% of the current 0.5-2 keV flux. Guided by this result, SN 1987A's X-ray spectra are modeled as the weighted sum of the non-equilibrium-ionization emission from two simple one-dimensional hydrodynamic simulations; this '2 Multiplication-Sign 1D' model reproduces the observed radii, light curves, and spectra with a minimum of free parameters. The interaction with the H II region ({rho}{sub init} Almost-Equal-To 130 amu cm{sup -3}, {+-} 15 Degree-Sign opening angle) produces the very broad emission lines and most of the 3-10 keV flux. Our ER hydrodynamics, admittedly a crude approximation to the multi-D reality, gives ER densities of {approx}10{sup 4} amu cm{sup -3}, requires dense clumps ( Multiplication-Sign 5.5 density enhancement in {approx}30% of the volume), and predicts that the 0.5-2 keV flux will drop at a rate of {approx}17% per year once no new dense ER material is being shocked.

  3. Past Test One

    E-Print Network [OSTI]

    MA 366: Introduction to Di?'erential Equations. Fall 2001, Test One. Instructor: Yip o This test booklet has FIVE QUESTIONS, totaling 50 points for the whole test.

  4. Advanced Vehicle Testing & Evaluation

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

    Vehicle Accelerated Reliability Test Battery Electric Vehicle Fast Charge Test Battery Energy Storage Performance Test For DC Fast Charge Demand Reduction...

  5. Combined Modeling of Acceleration, Transport, and Hydrodynamic Response in Solar Flares. II. Inclusion of Radiative Transfer with RADYN

    E-Print Network [OSTI]

    da Costa, Fatima Rubio; Petrosian, Vahe'; Carlsson, Mats

    2015-01-01T23:59:59.000Z

    Solar flares involve complex processes that are coupled together and span a wide range of temporal, spatial, and energy scales. Modeling such processes self-consistently has been a challenge in the past. Here we present such a model to simulate the coupling of high-energy particle kinetics with hydrodynamics of the atmospheric plasma. We combine the Stanford unified Fokker-Planck code that models particle acceleration, transport, and bremsstrahlung radiation with the RADYN hydrodynamic code that models the atmospheric response to collisional heating by non-thermal electrons through detailed radiative transfer calculations. We perform simulations using different injection electron spectra, including an {\\it ad hoc} power law and more realistic spectra predicted by the stochastic acceleration model due to turbulence or plasma waves. Surprisingly, stochastically accelerated electrons, even with energy flux $\\ll 10^{10}$ erg s$^{-1}$ cm$^{-2}$, cause "explosive" chromospheric evaporation and drive stronger up- an...

  6. Role of hydrodynamic instability growth in hot-spot mass gain and fusion performance of inertial confinement fusion implosions

    SciTech Connect (OSTI)

    Srinivasan, Bhuvana, E-mail: srinbhu@vt.edu [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Department of Aerospace and Ocean Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States); Tang, Xian-Zhu, E-mail: xtang@lanl.gov [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-10-15T23:59:59.000Z

    In an inertial confinement fusion target, energy loss due to thermal conduction from the hot-spot will inevitably ablate fuel ice into the hot-spot, resulting in a more massive but cooler hot-spot, which negatively impacts fusion yield. Hydrodynamic mix due to Rayleigh-Taylor instability at the gas-ice interface can aggravate the problem via an increased gas-ice interfacial area across which energy transfer from the hot-spot and ice can be enhanced. Here, this mix-enhanced transport effect on hot-spot fusion-performance degradation is quantified using contrasting 1D and 2D hydrodynamic simulations, and its dependence on effective acceleration, Atwood number, and ablation speed is identified.

  7. Computational Study of the Hydrodynamic Behavior during Air Discharge through a Sparger Submerged in the Condensation Pool

    SciTech Connect (OSTI)

    Ahn, Hyung-Joon; Bang, Young-Seok; Kim, In-Goo; Kim, Hho-Jung [Regulatory Research Div., Korea Institute of Nuclear Safety, 19 Kusongdong Yusongku Taejon (Korea, Republic of); Lee, Byeong-Eun; Kwon, Soon-Bum [School of Mech. Eng., Kyungpook National University, 1370, Sankyuk-dong, Puk-ku, Daegu 702-701 (Korea, Republic of)

    2002-07-01T23:59:59.000Z

    The In-containment Refueling Water Storage Tank (IRWST) has the function of heat sink when steam is released from the pressurizer. The hydrodynamic behaviors occurring at the sparger are very complex because of the wide variety of operating conditions and the complex geometry. Hydrodynamic behavior when air is discharged through a sparger in a condensation pool is investigated using CFD techniques in the present study. The effect of pressure acting on the sparger header during both water and air discharge through the sparger is studied. In addition, pressure oscillation occurring during air discharge through the sparger is studied for a better understanding of mechanisms of air discharge and a better design of the IRWST, including sparger. (authors)

  8. Two-and three-dimensional modeling and optimization applied to the design of a fast hydrodynamic focusing microfluidic mixer for protein folding

    E-Print Network [OSTI]

    Santiago, Juan G.

    focusing microfluidic mixer for protein folding Benjamin Ivorra, Juana L. Redondo, Juan G. Santiago, Pilar of a fast hydrodynamic focusing microfluidic mixer for protein folding Benjamin Ivorra,1,a) Juana L. Redondo

  9. Design of a free-running, 1/30th Froude scaled model destroyer for in-situ hydrodynamic flow visualization

    E-Print Network [OSTI]

    Cope, David M. (David Michael)

    2012-01-01T23:59:59.000Z

    Hydrodynamic flow visualization techniques of scaled hull forms and propellers are typically limited to isolating certain operating conditions in a tow tank, circulation tunnel, or large maneuvering basin. Although cost ...

  10. TEST STATION SALE OF PERFORMANCE TESTED BULLS

    E-Print Network [OSTI]

    Tennessee, University of

    in the test had to meet minimum performance requirements. Those were: CREEP NON-CREEP Adj 205 day wt. 560 520AS-B428 U T BULL TEST STATION SALE OF PERFORMANCE TESTED BULLS THURSDAY, MARCH 8, 2012 12:00 NOON IN GREENEVILLE AND KNOXVILLE LIVESTOCK CENTER http://animalscience.ag.utk.edu/ (For video) #12;UT BULL TEST

  11. The Post-Quasistatic Approximation as a test bed for Numerical Relativity

    E-Print Network [OSTI]

    W. Barreto

    2009-05-20T23:59:59.000Z

    It is shown that observers in the standard ADM 3+1 treatment of matter are the same as the observers used in the matter treatment of Bondi: they are comoving and local Minkowskian. Bondi's observers are the basis of the post--quasitatic approximation (PQSA) to study a contracting distribution of matter. This correspondence suggests the possibility of using the PQSA as a test bed for Numerical Relativity. The treatment of matter by the PQSA and its connection with the ADM 3+1 treatment are presented, for its practical use as a calibration tool and as a test bed for numerical relativistic hydrodynamic codes.

  12. Three-dimensional hydrodynamic simulations of the combustion of a neutron star into a quark star

    E-Print Network [OSTI]

    Matthias Herzog; Friedrich K. Roepke

    2011-09-02T23:59:59.000Z

    We present three-dimensional numerical simulations of turbulent combustion converting a neutron star into a quark star. Hadronic matter, described by a micro-physical finite-temperature equation of state, is converted into strange quark matter. We assume this phase, represented by a bag-model equation of state, to be absolutely stable. Following the example of thermonuclear burning in white dwarfs leading to Type Ia supernovae, we treat the conversion process as a potentially turbulent deflagration. Solving the non-relativistic Euler equations using established numerical methods we conduct large eddy simulations including an elaborate subgrid scale model, while the propagation of the conversion front is modeled with a level-set method. Our results show that for large parts of the parameter space the conversion becomes turbulent and therefore significantly faster than in the laminar case. Despite assuming absolutely stable strange quark matter, in our hydrodynamic approximation an outer layer remains in the hadronic phase, because the conversion front stops when it reaches conditions under which the combustion is no longer exothermic.

  13. Two-Dimensional Hydrodynamic Models of Super Star Clusters with a Positive Star Formation Feedback

    E-Print Network [OSTI]

    Wünsch, R; Palous, J; Silich, S

    2008-01-01T23:59:59.000Z

    Using the hydrodynamic code ZEUS, we perform 2D simulations to determine the fate of the gas ejected by massive stars within super star clusters. It turns out that the outcome depends mainly on the mass and radius of the cluster. In the case of less massive clusters, a hot high velocity ($\\sim 1000$ km s$^{-1}$) stationary wind develops and the metals injected by supernovae are dispersed to large distances from the cluster. On the other hand, the density of the thermalized ejecta within massive and compact clusters is sufficiently large as to immediately provoke the onset of thermal instabilities. These deplete, particularly in the central densest regions, the pressure and the pressure gradient required to establish a stationary wind, and instead the thermally unstable parcels of gas are rapidly compressed, by a plethora of re-pressurizing shocks, into compact high density condensations. Most of these are unable to leave the cluster volume and thus accumulate to eventually feed further generations of star for...

  14. Complexity Phenomena and ROMA of the Magnetospheric Cusp, Hydrodynamic Turbulence, and the Cosmic Web

    E-Print Network [OSTI]

    Tom Chang; Cheng-chin Wu; Marius Echim; Herve Lamy; Mark Vogelsberger; Lars Hernquist; Debora Sijacki

    2014-02-26T23:59:59.000Z

    Dynamic Complexity is a phenomenon exhibited by a nonlinearly interacting system within which multitudes of different sizes of large scale coherent structures emerge, resulting in a globally nonlinear stochastic behavior vastly different from that could be surmised from the underlying equations of interaction. The hallmark of such nonlinear, complex phenomena is the appearance of intermittent fluctuating events with the mixing and distributions of correlated structures at all scales. We briefly review here a relatively recent method, ROMA (rank-ordered multifractal analysis), explicitly constructed to analyze the intricate details of the distribution and scaling of such types of intermittent structures. This method is then applied to the analyses of selected examples related to the dynamical plasmas of the cusp region of the magnetosphere, velocity fluctuations of classical hydrodynamic turbulence, and the distribution of the structures of the cosmic gas obtained through large scale, moving mesh simulations. Differences and similarities of the analyzed results among these complex systems will be contrasted and highlighted. The first two examples have direct relevance to the geospace environment and are summaries of previously reported findings. The third example on the cosmic gas, though involving phenomena much larger in spatiotemporal scales, with its highly compressible turbulent behavior and the unique simulation technique employed in generating the data, provides direct motivations of applying such analysis to studies of similar multifractal processes in various extreme environments. These new results are both exciting and intriguing.

  15. Radiative hydrodynamic modelling and observations of the X-class solar flare on 2011 March 9

    E-Print Network [OSTI]

    Kennedy, Michael B; Allred, Joel C; Mathioudakis, Mihalis; Keenan, Francis P

    2015-01-01T23:59:59.000Z

    We investigated the response of the solar atmosphere to non-thermal electron beam heating using the radiative transfer and hydrodynamics modelling code RADYN. The temporal evolution of the parameters that describe the non-thermal electron energy distribution were derived from hard X-ray observations of a particular flare, and we compared the modelled and observed parameters. The evolution of the non-thermal electron beam parameters during the X1.5 solar flare on 2011 March 9 were obtained from analysis of RHESSI X-ray spectra. The RADYN flare model was allowed to evolve for 110 seconds, after which the electron beam heating was ended, and was then allowed to continue evolving for a further 300s. The modelled flare parameters were compared to the observed parameters determined from extreme-ultraviolet spectroscopy. The model produced a hotter and denser flare loop than that observed and also cooled more rapidly, suggesting that additional energy input in the decay phase of the flare is required. In the explosi...

  16. The dynamical mass ejection from binary neutron star mergers: Radiation-hydrodynamics study in general relativity

    E-Print Network [OSTI]

    Sekiguchi, Yuichiro; Kyutoku, Koutarou; Shibata, Masaru

    2015-01-01T23:59:59.000Z

    We perform radiation-hydrodynamics simulations of binary neutron star mergers in numerical relativity on the Japanese "K" supercomputer, taking into account neutrino cooling and heating by an updated leakage-plus-transfer scheme for the first time. Neutron stars are modeled by three modern finite-temperature equations of state (EOS) developed by Hempel and his collaborators. We find that the electron fraction has a broad distribution due to the weak processes and shock heating. The properties of the ejecta such as total mass, average electron fraction, and thermal energy depend strongly on the EOS. Only for a soft EOS (the so-called SFHo), the ejecta mass exceeds $0.01M_{\\odot}$. In this case, the electron fraction has a broad distribution which is well-suited for the production of the solar-like $r$-process abundance. For the other stiff EOS (DD2 and TM1), for which a long-lived massive neutron star is formed after the merger, the ejecta mass is smaller than $0.01M_{\\odot}$, although broad electron-fraction ...

  17. Abundance anomalies in metal-poor stars from Population III supernova ejecta hydrodynamics

    E-Print Network [OSTI]

    Sluder, Alan; Safranek-Shrader, Chalence; Milosavljevic, Milos; Bromm, Volker

    2015-01-01T23:59:59.000Z

    We present a simulation of the long-term evolution of a Population III supernova remnant in a cosmological minihalo. Employing passive Lagrangian tracer particles, we investigate how chemical stratification and anisotropy in the explosion can affect the abundances of the first low-mass, metal-enriched stars. We find that reverse shock heating can leave the inner mass shells at entropies too high to cool, leading to carbon-enhancement in the re-collapsing gas. This hydrodynamic selection effect could explain the observed incidence of carbon-enhanced metal-poor (CEMP) stars at low metallicity. We further explore how anisotropic ejecta distributions, recently seen in direct numerical simulations of core-collapse explosions, may translate to abundances in metal-poor stars. We find that some of the observed scatter in the Population II abundance ratios can be explained by an incomplete mixing of supernova ejecta, even in the case of only one contributing enrichment event. We demonstrate that the customary hypothes...

  18. Thermo-Hydrodynamics of Circumstellar Disks with High-mass Planets

    E-Print Network [OSTI]

    Gennaro D'Angelo; Thomas Henning; Willy Kley

    2003-09-08T23:59:59.000Z

    With a series of numerical simulations, we analyze the thermo-hydrodynamical evolution of circumstellar disks containing Jupiter-size protoplanets. In the framework of the two-dimensional approximation, we consider an energy equation that includes viscous heating and radiative effects in a simplified, yet consistent form. Multiple nested grids are used in order to study both global and local features around the planet. By means of different viscosity prescriptions, we investigate various temperature regimes. A planetary mass range from 0.1 to 1 Mj is examined. Computations show that gap formation is a general property which affects density, pressure, temperature, optical thickness, and radiated flux distributions. However, it remains a prominent feature only when the kinematic viscosity is on the order of 10^(15) cm^2/s or lower. Around accreting planets, a circumplanetary disk forms that has a surface density profile decaying exponentially with the distance and whose mass is 5-6 orders of magnitudes smaller than Jupiter's mass. Circumplanetary disk temperature profiles decline roughly as the inverse of the distance from the planet. Temperatures range from some 10 to ~1000 K. Planetary accretion and migration rates depend on the viscosity regime, with discrepancies within an order of magnitude. Estimates of growth and migration time scales inferred by these models are on the same orders of magnitude as those previously obtained with locally isothermal simulations.

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

    SciTech Connect (OSTI)

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

    2009-04-01T23:59:59.000Z

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

  20. Design of an electromagnetic accelerator for turbulent hydrodynamic mix studies. Revision 1

    SciTech Connect (OSTI)

    Susoeff, A.R.; Hawke, R.S.; Morrison, J.J.; Dimonte, G.; Remington, B.A.

    1994-03-01T23:59:59.000Z

    An electromagnetic accelerator in the form of a linear electric motor (LEM) has been designed to achieve controlled acceleration profiles of a carriage containing hydrodynamically unstable fluids for the investigation of the development of turbulent mix. Key features of the design include: (1) independent control of acceleration, deceleration and augmentation currents to provide a variety of acceleration-time profiles, (2) a robust support structure to minimized deflection and dampen vibration which could create artifacts in the data interfering with the intended study and (3) a compliant, non-arcing solid armature allowing optimum electrical contact. Electromagnetic modeling codes were used to optimize the rail and augmentation coil positions within the support structure framework. Design of the driving armature and the dynamic electromagnetic braking system is based on results of contemporary studies for non-arcing sliding contact of solid armatures. A 0.6MJ electrolytic capacitor bank is used for energy storage to drive the LEM. This report will discuss a LEM and armature design which will accelerate masses of up to 3kg to a maximum of about 3000g{sub o}, where g{sub o} is acceleration due to gravity.

  1. Discrete Boltzmann modeling of multiphase flows: hydrodynamic and thermodynamic non-equilibrium effects

    E-Print Network [OSTI]

    Yanbiao Gan; Aiguo Xu; Guangcai Zhang; Sauro Succi

    2015-05-11T23:59:59.000Z

    A discrete Boltzmann model (DBM) is developed to investigate the hydrodynamic and thermodynamic non-equilibrium (TNE) effects in phase separation processes. The interparticle force drives changes and the gradient force, induced by gradients of macroscopic quantities, opposes them. In this paper, we investigate the interplay between them by providing detailed inspection of various non-equilibrium observables. Based on the TNE features, we define a TNE strength which roughly estimates the deviation amplitude from the thermodynamic equilibrium. The time evolution of the TNE intensity provides a convenient and efficient physical criterion to discriminate the stages of the spinodal decomposition and domain growth. Via the DBM simulation and this criterion, we quantitatively study the effects of latent heat and surface tension on phase separation. It is found that, the TNE strength attains its maximum at the end of the spinodal decomposition stage, and it decreases when the latent heat increases from zero. The surface tension effects are threefold, to prolong the duration of the spinodal decomposition stage, decrease the maximum TNE intensity, and accelerate the speed of the domain growth stage.

  2. A High Resolution Hydrodynamic Model of Puget Sound to Support Nearshore Restoration Feasibility Analysis and Design

    SciTech Connect (OSTI)

    Khangaonkar, Tarang; Yang, Zhaoqing

    2011-01-01T23:59:59.000Z

    Estuarine and coastal hydrodynamic processes are sometimes neglected in the design and planning of nearshore restoration actions. Despite best intentions, efforts to restore nearshore habitats can result in poor outcomes if circulation and transport which also affect freshwater-saltwater interactions are not properly addressed. Limitations due to current land use can lead to selection of sub-optimal restoration alternatives that may result in undesirable consequences, such as flooding, deterioration of water quality, and erosion, requiring immediate remedies and costly repairs. Uncertainty with achieving restoration goals, such as recovery of tidal exchange, supply of sediment and nutrients, and establishment of fish migration pathways, may be minimized by using numerical models designed for application to the nearshore environment. A high resolution circulation and transport model of the Puget Sound, in the state of Washington, was developed to assist with nearshore habitat restoration design and analysis, and to answer the question “can we achieve beneficial restoration outcomes at small local scale, as well as at a large estuary-wide scale?” The Puget Sound model is based on an unstructured grid framework to define the complex Puget Sound shoreline using a finite volume coastal ocean model (FVCOM). The capability of the model for simulating the important nearshore processes, such as circulation in complex multiple tidal channels, wetting and drying of tide flats, and water quality and sediment transport as part of restoration feasibility, are illustrated through examples of restoration projects in Puget Sound.

  3. Confronting Hydrodynamic Simulations Of Relativistic Jets With Data: What Do We Learn About Particles & Fields?

    E-Print Network [OSTI]

    Philip A. Hughes

    2000-11-06T23:59:59.000Z

    We review recent relativistic hydrodynamic simulations of jets, and their interpretation in terms of the results from linear stability analysis. These studies show that, interpreted naively, the distribution of synchrotron intensity will in general be a poor guide to the physical state (density and pressure) of the underlying flow, and that even if the physical state can be inferred, it, in turn, may prove to be a poor guide to the source dynamics, in terms of the transport of energy and momentum from the central engine. However, we demonstrate that an interplay of simulation and linear stability analysis provides a powerful tool for elucidating the nature and character of structures that jets may sustain. From such studies we can explain the complex behavior of observed jets, which manifest both stationary and propagating structures, without recourse to ad hoc macroscopic disturbances. This provides a framework for the interpretation of multi-epoch total intensity data wherein an understanding of the character of individual flow features will allow the effects of physical state and dynamics to be deconvolved.

  4. A new multidimensional, energy-dependent two-moment transport code for neutrino-hydrodynamics

    E-Print Network [OSTI]

    Just, Oliver; Janka, H -Thomas

    2015-01-01T23:59:59.000Z

    We present the new code ALCAR developed to model multidimensional, multi energy-group neutrino transport in the context of supernovae and neutron-star mergers. The algorithm solves the evolution equations of the 0th- and 1st-order angular moments of the specific intensity, supplemented by an algebraic relation for the 2nd-moment tensor to close the system. The scheme takes into account frame-dependent effects of order O(v/c) as well as the most important types of neutrino interactions. The transport scheme is significantly more efficient than a multidimensional solver of the Boltzmann equation, while it is more accurate and consistent than the flux-limited diffusion method. The finite-volume discretization of the essentially hyperbolic system of moment equations employs methods well-known from hydrodynamics. For the time integration of the potentially stiff moment equations we employ a scheme in which only the local source terms are treated implicitly, while the advection terms are kept explicit, thereby allo...

  5. Simulating (electro)hydrodynamic effects in colloidal dispersions: smoothed profile method

    E-Print Network [OSTI]

    Yasuya Nakayama; Kang Kim; Ryoichi Yamamoto

    2008-05-09T23:59:59.000Z

    Previously, we have proposed a direct simulation scheme for colloidal dispersions in a Newtonian solvent [Phys.Rev.E 71,036707 (2005)]. An improved formulation called the ``Smoothed Profile (SP) method'' is presented here in which simultaneous time-marching is used for the host fluid and colloids. The SP method is a direct numerical simulation of particulate flows and provides a coupling scheme between the continuum fluid dynamics and rigid-body dynamics through utilization of a smoothed profile for the colloidal particles. Moreover, the improved formulation includes an extension to incorporate multi-component fluids, allowing systems such as charged colloids in electrolyte solutions to be studied. The dynamics of the colloidal dispersions are solved with the same computational cost as required for solving non-particulate flows. Numerical results which assess the hydrodynamic interactions of colloidal dispersions are presented to validate the SP method. The SP method is not restricted to particular constitutive models of the host fluids and can hence be applied to colloidal dispersions in complex fluids.

  6. Solar Flare Chromospheric Line Emission: Comparison Between IBIS High-resolution Observations and Radiative Hydrodynamic Simulations

    E-Print Network [OSTI]

    da Costa, Fatima Rubio; Petrosian, Vahé; Dalda, Alberto Sainz; Liu, Wei

    2014-01-01T23:59:59.000Z

    Solar flares involve impulsive energy release, which results in enhanced radiation in a broad spectral and at a wide height range. In particular, line emission from the chromosphere (lower atmosphere) can provide critical diagnostics of plasma heating processes. Thus, a direct comparison between high-resolution spectroscopic observations and advanced numerical modeling results can be extremely valuable, but has not been attempted so far. We present in this paper such a self-consistent investigation of an M3.0 flare observed by the Dunn Solar Telescope's (DST) Interferometric Bi-dimensional Spectrometer (IBIS) on 2011 September 24 that we have modeled with the radiative hydrodynamic code RADYN (Carlsson & Stein 1992, 1997; Abbett & Hawley 1999; Allred et al. 2005). We obtained images and spectra of the flaring region with IBIS in H$\\alpha$ 6563 \\AA\\ and Ca II 8542 \\AA, and with the Reuven Ramaty High Energy Solar Spectroscope Imager (RHESSI) in X-rays. The latter was used to infer the non-thermal elect...

  7. Center-to-Limb Variation of Solar 3-D Hydrodynamical Simulations

    E-Print Network [OSTI]

    L. Koesterke; C. Allende Prieto; D. L. Lambert

    2008-02-15T23:59:59.000Z

    We examine closely the solar Center-to-Limb variation of continua and lines and compare observations with predictions from both a 3-D hydrodynamic simulation of the solar surface (provided by M. Asplund and collaborators) and 1-D model atmospheres. Intensities from the 3-D time series are derived by means of the new synthesis code ASSET, which overcomes limitations of previously available codes by including a consistent treatment of scattering and allowing for arbitrarily complex line and continuum opacities. In the continuum, we find very similar discrepancies between synthesis and observation for both types of model atmospheres. This is in contrast to previous studies that used a ``horizontally'' and time averaged representation of the 3-D model and found a significantly larger disagreement with observations. The presence of temperature and velocity fields in the 3-D simulation provides a significant advantage when it comes to reproduce solar spectral line shapes. Nonetheless, a comparison of observed and synthetic equivalent widths reveals that the 3-D model also predicts more uniform abundances as a function of position angle on the disk. We conclude that the 3-D simulation provides not only a more realistic description of the gas dynamics, but, despite its simplified treatment of the radiation transport, it also predicts reasonably well the observed Center-to-Limb variation, which is indicative of a thermal structure free from significant systematic errors.

  8. Hydrodynamic injection with pneumatic valving for microchip electrophoresis with total analyte utilization

    SciTech Connect (OSTI)

    Sun, Xuefei; Kelly, Ryan T.; Danielson, William F.; Agrawal, Nitin; Tang, Keqi; Smith, Richard D.

    2011-04-26T23:59:59.000Z

    A novel hydrodynamic injector that is directly controlled by a pneumatic valve has been developed for reproducible microchip capillary electrophoresis (CE) separations. The poly(dimethylsiloxane) (PDMS) devices used for evaluation comprise a separation channel, a side channel for sample introduction, and a pneumatic valve aligned at the intersection of the channels. A low pressure (? 3 psi) applied to the sample reservoir is sufficient to drive sample into the separation channel. The rapidly actuated pneumatic valve enables injection of discrete sample plugs as small as ~100 pL for CE separation. The injection volume can be easily controlled by adjusting the intersection geometry, the solution back pressure and the valve actuation time. Sample injection could be reliably operated at different frequencies (< 0.1 Hz to >2 Hz) with good reproducibility (peak height relative standard deviation ? 3.6%) and no sampling biases associated with the conventional electrokinetic injections. The separation channel was dynamically coated with a cationic polymer, and FITC-labeled amino acids were employed to evaluate the CE separation. Highly efficient (? 7.0 × 103 theoretical plates for the ~2.4 cm long channel) and reproducible CE separations were obtained. The demonstrated method has numerous advantages compared with the conventional techniques, including repeatable and unbiased injections, no sample waste, high duty cycle, controllable injected sample volume, and fewer electrodes with no need for voltage switching. The prospects of implementing this injection method for coupling multidimensional separations, for multiplexing CE separations and for sample-limited bioanalyses are discussed.

  9. Hydrodynamical simulations of the decay of high-speed molecular turbulence. I. Dense molecular regions

    E-Print Network [OSTI]

    Georgi Pavlovski; Michael D. Smith; Mordecai-Mark Mac Low; Alexander Rosen

    2002-08-15T23:59:59.000Z

    We present the results from three dimensional hydrodynamical simulations of decaying high-speed turbulence in dense molecular clouds. We compare our results, which include a detailed cooling function, molecular hydrogen chemistry and a limited C and O chemistry, to those previously obtained for decaying isothermal turbulence. After an initial phase of shock formation, power-law decay regimes are uncovered, as in the isothermal case. We find that the turbulence decays faster than in the isothermal case because the average Mach number remains higher, due to the radiative cooling. The total thermal energy, initially raised by the introduction of turbulence, decays only a little slower than the kinetic energy. We discover that molecule reformation, as the fast turbulence decays, is several times faster than that predicted for a non-turbulent medium. This is caused by moderate speed shocks which sweep through a large fraction of the volume, compressing the gas and dust. Through reformation, the molecular density and molecular column appear as complex patterns of filaments, clumps and some diffuse structure. In contrast, the molecular fraction has a wider distribution of highly distorted clumps and copious diffuse structure, so that density and molecular density are almost identically distributed during the reformation phase. We conclude that molecules form in swept-up clumps but effectively mix throughout via subsequent expansions and compressions.

  10. Hydrodynamic Modeling of Air Blast Propagation from the Humble Redwood Chemical High Explosive Detonations Using GEODYN

    SciTech Connect (OSTI)

    Chipman, V D

    2011-09-20T23:59:59.000Z

    Two-dimensional axisymmetric hydrodynamic models were developed using GEODYN to simulate the propagation of air blasts resulting from a series of high explosive detonations conducted at Kirtland Air Force Base in August and September of 2007. Dubbed Humble Redwood I (HR-1), these near-surface chemical high explosive detonations consisted of seven shots of varying height or depth of burst. Each shot was simulated numerically using GEODYN. An adaptive mesh refinement scheme based on air pressure gradients was employed such that the mesh refinement tracked the advancing shock front where sharp discontinuities existed in the state variables, but allowed the mesh to sufficiently relax behind the shock front for runtime efficiency. Comparisons of overpressure, sound speed, and positive phase impulse from the GEODYN simulations were made to the recorded data taken from each HR-1 shot. Where the detonations occurred above ground or were shallowly buried (no deeper than 1 m), the GEODYN model was able to simulate the sound speeds, peak overpressures, and positive phase impulses to within approximately 1%, 23%, and 6%, respectively, of the actual recorded data, supporting the use of numerical simulation of the air blast as a forensic tool in determining the yield of an otherwise unknown explosion.

  11. A hydrodynamic model for asymmetric explosions of rapidly rotating collapsing supernovae with a toroidal atmosphere

    E-Print Network [OSTI]

    V. S. Imshennik; K. V. Manukovskii

    2004-11-16T23:59:59.000Z

    We numerically solved the two-dimensional axisymmetric hydrodynamic problem of the explosion of a low-mass neutron star in a circular orbit. In the initial conditions, we assumed a nonuniform density distribution in the space surrounding the collapsed iron core in the form of a stationary toroidal atmosphere that was previously predicted analytically and computed numerically. The con?guration of the exploded neutron star itself was modeled by a torus with a circular cross section whose central line almost coincided with its circular orbit. Using an equation of state for the stellar matter and the toroidal atmosphere in which the nuclear statistical equilibrium conditions were satisfied, we performed a series of numerical calculations that showed the propagation of a strong divergent shock wave with a total energy of 0.2x10^51 erg at initial explosion energy release of 1.0x10^51 erg. In our calculations, we rigorously took into account the gravitational interaction, including the attraction from a higher-mass (1.9M_solar) neutron star located at the coordinate origin, in accordance with the rotational explosion mechanism for collapsing supernovae.W e compared in detail our results with previous similar results of asymmetric supernova explosion simulations and concluded that we found a lower limit for the total explosion energy.

  12. Quantum maximum-entropy principle for closed quantum hydrodynamic transport within a Wigner function formalism

    SciTech Connect (OSTI)

    Trovato, M. [Dipartimento di Matematica, Universita di Catania, Viale A. Doria, I-95125 Catania (Italy); Reggiani, L. [Dipartimento di Ingegneria dell' Innovazione and CNISM, Universita del Salento, Via Arnesano s/n, I-73100 Lecce (Italy)

    2011-12-15T23:59:59.000Z

    By introducing a quantum entropy functional of the reduced density matrix, the principle of quantum maximum entropy is asserted as fundamental principle of quantum statistical mechanics. Accordingly, we develop a comprehensive theoretical formalism to construct rigorously a closed quantum hydrodynamic transport within a Wigner function approach. The theoretical formalism is formulated in both thermodynamic equilibrium and nonequilibrium conditions, and the quantum contributions are obtained by only assuming that the Lagrange multipliers can be expanded in powers of ({h_bar}/2{pi}){sup 2}. In particular, by using an arbitrary number of moments, we prove that (1) on a macroscopic scale all nonlocal effects, compatible with the uncertainty principle, are imputable to high-order spatial derivatives, both of the numerical density n and of the effective temperature T; (2) the results available from the literature in the framework of both a quantum Boltzmann gas and a degenerate quantum Fermi gas are recovered as a particular case; (3) the statistics for the quantum Fermi and Bose gases at different levels of degeneracy are explicitly incorporated; (4) a set of relevant applications admitting exact analytical equations are explicitly given and discussed; (5) the quantum maximum entropy principle keeps full validity in the classical limit, when ({h_bar}/2{pi}){yields}0.

  13. Modelling the high-energy emission from gamma-ray binaries using numerical relativistic hydrodynamics

    E-Print Network [OSTI]

    Dubus, Guillaume; Fromang, Sébastien

    2015-01-01T23:59:59.000Z

    Detailed modeling of the high-energy emission from gamma-ray binaries has been propounded as a path to pulsar wind physics. Fulfilling this ambition requires a coherent model of the flow and its emission in the region where the pulsar wind interacts with the stellar wind of its companion. We developed a code that follows the evolution and emission of electrons in the shocked pulsar wind based on inputs from a relativistic hydrodynamical simulation. The code is used to model the well-documented spectral energy distribution and orbital modulations from LS 5039. The pulsar wind is fully confined by a bow shock and a back shock. The particles are distributed into a narrow Maxwellian, emitting mostly GeV photons, and a power law radiating very efficiently over a broad energy range from X-rays to TeV gamma rays. Most of the emission arises from the apex of the bow shock. Doppler boosting shapes the X-ray and VHE lightcurves, constraining the system inclination to $i\\approx 35^{\\rm o}$. There is a tension between th...

  14. The solar photospheric abundance of europium. Results from CO5BOLD 3-D hydrodynamical model atmospheres

    E-Print Network [OSTI]

    A. Mucciarelli; E. Caffau; B. Freytag; H. -G. Ludwig; P. Bonifacio

    2008-03-06T23:59:59.000Z

    Context. Europium is an almost pure r-process element, which may be useful as a reference in nucleocosmochronology. Aims. To determine the photospheric solar abundance using CO5BOLD 3-D hydrodynamical model atmospheres. Methods. Disc-centre and integrated-flux observed solar spectra are used. The europium abundance is derived from the equivalent width measurements. As a reference 1D model atmospheres have been used, in addition. Results. The europium photospheric solar abundance is 0.52 +- 0.02 in agreement with previous determinations. We also determine the photospheric isotopic fraction of Eu(151) to be 49 % +- 2.3 % from the intensity spectra and 50% +-2.3 from the flux spectra. This compares well to the the meteoritic isotopic fraction 47.8%. We explore the 3D corrections also for dwarfs and sub-giants in the temperature range ~5000 K to ~6500 K and solar and 1/10--solar metallicities and find them to be negligible for all the models investigated. Conclusions. Our photospheric Eu abundance is in good agreement with previous determinations based on 1D models. This is in line with our conclusion that 3D effects for this element are negligible in the case of the Sun.

  15. The solar photospheric abundance of europium. Results from CO5BOLD 3-D hydrodynamical model atmospheres

    E-Print Network [OSTI]

    Mucciarelli, A; Freytag, B; Ludwig, H -G; Bonifacio, P

    2008-01-01T23:59:59.000Z

    Context. Europium is an almost pure r-process element, which may be useful as a reference in nucleocosmochronology. Aims. To determine the photospheric solar abundance using CO5BOLD 3-D hydrodynamical model atmospheres. Methods. Disc-centre and integrated-flux observed solar spectra are used. The europium abundance is derived from the equivalent width measurements. As a reference 1D model atmospheres have been used, in addition. Results. The europium photospheric solar abundance is 0.52 +- 0.02 in agreement with previous determinations. We also determine the photospheric isotopic fraction of Eu(151) to be 49 % +- 2.3 % from the intensity spectra and 50% +-2.3 from the flux spectra. This compares well to the the meteoritic isotopic fraction 47.8%. We explore the 3D corrections also for dwarfs and sub-giants in the temperature range ~5000 K to ~6500 K and solar and 1/10--solar metallicities and find them to be negligible for all the models investigated. Conclusions. Our photospheric Eu abundance is in good agre...

  16. Simulations of Liners and Test Objects for a New Atlas Advanced Radiography Source

    SciTech Connect (OSTI)

    D. V. Morgan; S. Iversen; R. A. Hilko

    2002-06-01T23:59:59.000Z

    The Advanced Radiographic Source (ARS) will improve the data significantly due to its smaller source width. Because of the enhanced ARS output, larger source-to-object distances are a reality. The harder ARS source will allow radiography of thick high-Z targets. The five different spectral simulations resulted in similar imaging detector weighted transmission. This work used a limited set of test objects and imaging detectors. Other test objects and imaging detectors could possibly change the MVp-sensitivity result. The effect of material motion blur must be considered for the ARS due to the expected smaller X-ray source size. This study supports the original 1.5-MVp value.

  17. Using Phased Array Ultrasonic Testing in Lieu of Radiography for Acceptance of Carbon Steel Piping Welds

    SciTech Connect (OSTI)

    Moran, Traci L.; Anderson, Michael T.; Cinson, Anthony D.; Crawford, Susan L.; Nove, Carol A.

    2014-08-01T23:59:59.000Z

    The Pacific Northwest National Laboratory (PNNL) is conducting studies for the U.S. Nuclear Regulatory Commission (NRC) to assess the capability, effectiveness, and reliability of ultrasonic testing (UT) as a replacement method for radiographic testing (RT) for volumetric examination of nuclear power plant (NPP) components. This particular study focused on evaluating the use of UT on carbon steel plate welds. Welding fabrication flaws included a combination of planar and volumetric types, e.g., incomplete fusion, lack of penetration, cracks, porosity, and slag inclusions. The examinations were conducted using phased-array (PA) UT techniques applied primarily for detection and flaw type characterization. This paper will discuss the results of using UT in lieu of RT for detection and classification of fabrication flaws in carbon steel plate welds.

  18. Advanced Vehicle Testing - Beginning-of-Test Battery Testing...

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

    2.5 V Thermal Mgmt.: Passive, Vacuum-Sealed Unit Pack Weight: 294 kg BATTERY LABORATORY TEST RESULTS SUMMARY Vehicle Mileage and Testing Date Vehicle Odometer: 6,696 mi Date of...

  19. Plasmon excitation in metal slab by fast point charge: The role of additional boundary conditions in quantum hydrodynamic model

    SciTech Connect (OSTI)

    Zhang, Ying-Ying [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); An, Sheng-Bai; Song, Yuan-Hong, E-mail: songyh@dlut.edu.cn; Wang, You-Nian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Kang, Naijing [Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Miškovi?, Z. L., E-mail: zmiskovi@uwaterloo.ca [Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2014-10-15T23:59:59.000Z

    We study the wake effect in the induced potential and the stopping power due to plasmon excitation in a metal slab by a point charge moving inside the slab. Nonlocal effects in the response of the electron gas in the metal are described by a quantum hydrodynamic model, where the equation of electronic motion contains both a quantum pressure term and a gradient correction from the Bohm quantum potential, resulting in a fourth-order differential equation for the perturbed electron density. Thus, besides using the condition that the normal component of the electron velocity should vanish at the impenetrable boundary of the metal, a consistent inclusion of the gradient correction is shown to introduce two possibilities for an additional boundary condition for the perturbed electron density. We show that using two different sets of boundary conditions only gives rise to differences in the wake potential at large distances behind the charged particle. On the other hand, the gradient correction in the quantum hydrodynamic model is seen to cause a reduction in the depth of the potential well closest to the particle, and a reduction of its stopping power. Even for a particle moving in the center of the slab, we observe nonlocal effects in the induced potential and the stopping power due to reduction of the slab thickness, which arise from the gradient correction in the quantum hydrodynamic model.

  20. Bull Test ID 1118 2013 Florida Bull Test

    E-Print Network [OSTI]

    Jawitz, James W.

    Bull Test ID 1118 2013 Florida Bull Test #12;Bull Test ID 1119 2013 Florida Bull Test #12;Bull Test ID 1120 2013 Florida Bull Test #12;Bull Test ID 1121 2013 Florida Bull Test #12;Bull Test ID 1122 2013 Florida Bull Test #12;Bull Test ID 1123 2013 Florida Bull Test #12;Bull Test ID 1124 2013 Florida

  1. Bull Test ID 1181 2013 Florida Bull Test

    E-Print Network [OSTI]

    Jawitz, James W.

    Bull Test ID 1181 2013 Florida Bull Test #12;Bull Test ID 1182 2013 Florida Bull Test #12;Bull Test ID 1183 2013 Florida Bull Test #12;Bull Test ID 1184 2013 Florida Bull Test #12;Bull Test ID 1185 2013 Florida Bull Test #12;Bull Test ID 1186 2013 Florida Bull Test #12;Bull Test ID 1187 2013 Florida

  2. Bull Test ID 1098 2013 Florida Bull Test

    E-Print Network [OSTI]

    Jawitz, James W.

    Bull Test ID 1098 2013 Florida Bull Test #12;Bull Test ID 1099 2013 Florida Bull Test #12;Bull Test ID 1100 2013 Florida Bull Test #12;Bull Test ID 1101 2013 Florida Bull Test #12;Bull Test ID 1102 2013 Florida Bull Test #12;Bull Test ID 1103 2013 Florida Bull Test #12;Bull Test ID 1104 2013 Florida

  3. Bull Test ID 1160 2013 Florida Bull Test

    E-Print Network [OSTI]

    Jawitz, James W.

    Bull Test ID 1160 2013 Florida Bull Test #12;Bull Test ID 1161 2013 Florida Bull Test #12;Bull Test ID 1162 2013 Florida Bull Test #12;Bull Test ID 1163 2013 Florida Bull Test #12;Bull Test ID 1164 2013 Florida Bull Test #12;Bull Test ID 1165 2013 Florida Bull Test #12;Bull Test ID 1166 2013 Florida

  4. Bull Test ID 1077 2013 Florida Bull Test

    E-Print Network [OSTI]

    Jawitz, James W.

    14th Annual Florida Bull Test #12;Bull Test ID 1077 2013 Florida Bull Test #12;Bull Test ID 1078 2013 Florida Bull Test #12;Bull Test ID 1079 2013 Florida Bull Test #12;Bull Test ID 1080 2013 Florida Bull Test #12;Bull Test ID 1081 2013 Florida Bull Test #12;Bull Test ID 1082 2013 Florida Bull Test #12

  5. Bull Test ID 1140 2013 Florida Bull Test

    E-Print Network [OSTI]

    Jawitz, James W.

    Bull Test ID 1140 2013 Florida Bull Test #12;Bull Test ID 1141 2013 Florida Bull Test #12;Bull Test ID 1142 2013 Florida Bull Test #12;Bull Test ID 1143 2013 Florida Bull Test #12;Bull Test ID 1144 2013 Florida Bull Test #12;Bull Test ID 1145 2013 Florida Bull Test #12;Bull Test ID 1146 2013 Florida

  6. Concolic Testing Koushik Sen

    E-Print Network [OSTI]

    Sen, Koushik

    Concolic testing automates test input generation by com­ bining the concrete and symbolic (concolic) execution of the code under test. Traditional test input generation tech­ niques use either (1) concrete test inputs from these constraints. In contrast, concolic testing tightly couples both concrete

  7. Concolic Testing Koushik Sen

    E-Print Network [OSTI]

    Sen, Koushik

    Concolic testing automates test input generation by com- bining the concrete and symbolic (concolic) execution of the code under test. Traditional test input generation tech- niques use either (1) concrete test inputs from these constraints. In contrast, concolic testing tightly couples both concrete

  8. Test Series 2. 3 detailed test plan

    SciTech Connect (OSTI)

    Not Available

    1983-12-01T23:59:59.000Z

    Test Series 2.3 is chronologically the second of the five sub-series of tests which comprise Test Series 2, the second major Test Series as part of the combustion research phase to be carried out at the Grimethorpe Experimental Pressurised Fluidised Bed Combustion Facility. Test Series 2.3 will consist of 700 data gathering hours which is expected to require some 1035 coal burning hours. The tests will be performed using US supplied coal and dolomite. This will be the first major series of tests on the Facility with other than the UK datum coal and dolomite. The document summarises the background to the facility and the experimental program. Described are modifications which have been made to the facility following Test Series 2.1 and a series of Screening Tests. Detailed test objectives are specified as are the test conditions for the experiments which comprise the test series. The test results will provide information on the effects of the bed temperature, excess air level, Ca/S ratio, number of coal feed lines, and combustion efficiency and sulphur retention. A significant aspect of the test series will be part load tests which will investigate the performance of the facility under conditions of turn down which simulate load following concepts specified for two combined cycle concepts, i.e., their CFCC combined cycle and a turbo charged combined cycle. The material test plan is also presented. The principal feature of the materials programme is the planned exposure of a set of static turbine blade specimens in a cascade test loop to the high temperature, high pressure flue gas. A schedule for the programme is presented as are contingency plans.

  9. A Coupled THMC model of FEBEX mock-up test

    SciTech Connect (OSTI)

    Zheng, Liange; Samper, Javier

    2008-09-15T23:59:59.000Z

    FEBEX (Full-scale Engineered Barrier EXperiment) is a demonstration and research project for the engineered barrier system (EBS) of a radioactive waste repository in granite. It includes two full-scale heating and hydration tests: the in situ test performed at Grimsel (Switzerland) and a mock-up test operating at CIEMAT facilities in Madrid (Spain). The mock-up test provides valuable insight on thermal, hydrodynamic, mechanical and chemical (THMC) behavior of EBS because its hydration is controlled better than that of in situ test in which the buffer is saturated with water from the surrounding granitic rock. Here we present a coupled THMC model of the mock-up test which accounts for thermal and chemical osmosis and bentonite swelling with a state-surface approach. The THMC model reproduces measured temperature and cumulative water inflow data. It fits also relative humidity data at the outer part of the buffer, but underestimates relative humidities near the heater. Dilution due to hydration and evaporation near the heater are the main processes controlling the concentration of conservative species while surface complexation, mineral dissolution/precipitation and cation exchanges affect significantly reactive species as well. Results of sensitivity analyses to chemical processes show that pH is mostly controlled by surface complexation while dissolved cations concentrations are controlled by cation exchange reactions.

  10. Near wake models for the hydrodynamics forces on a cylinder in periodic flow

    SciTech Connect (OSTI)

    Sibetheros, I.A.; Medeiros, E.F. [Univ. of Texas, Austin, TX (United States); Miksad, R.W. [Univ. of Virginia, Charlottesville, VA (United States). School of Engineering and Applied Science

    1995-12-31T23:59:59.000Z

    The relationship between hydrodynamic forces and the reversing near wake flow field around a cylinder in oscillatory farfield flow was experimentally investigated. A computer controlled pressurized water tunnel was employed to generate a planar harmonic flow past a stationary cylinder of Keulegan-Carpenter numbers (KC) in the inertia-drag flow regime and at subcritical Reynolds numbers (Re). Streamwise (u-) and cross-stream (v-) velocities near the cylinder and u-velocities at the far flow field were measured using a three-component LDV system. Inline and lift forces on the cylinder were measured using a very sensitive six-component load cell. A modal phase averaging technique was applied to the velocity data to estimate averaged velocity cycles that distinguish between positive and negative flow modes. A positive (negative) flow mode signifies dominant vortex shedding and motion occurring from the top (bottom) of the cylinder, respectively. The force measurements were likewise phase averaged into positive and negative mode force cycles. u- and v-velocity profiles for KC = 10, 15, and 20, based on modal phase averages of velocity measurements, were used to estimate averaged wake u- and v-velocities. These wake velocities were used in the place of the undisturbed farfield u-velocity as inputs to Morison`s equation for the inline force, and to the quasi-steady model for the lift force. It was found that, for KC = 15 a significant improvement in the prediction of lift force was achieved using the wake-based lift force model, whereas a smaller improvement in the inline force prediction was obtained from the wake-based Morison`s equation.

  11. Hydrodynamic trapping in Mission Canyon Formation (Mississippian) reservoirs: Elkhorn Ranch field, North Dakota

    SciTech Connect (OSTI)

    Demis, W.D. (Marathon Oil Co., Houston, TX (United States))

    1991-03-01T23:59:59.000Z

    Hydrocarbons in Mission Canyon dolomite reservoirs in the Elkhorn Ranch field are trapped by downdip flow of formation water to the northeast. Elkhorn Ranch field is located on a north-plunging anticline with only 10 ft (3 m) of crestal closure. The Mission Canyon is a regressive, shallowing upward sequence of subtidal dolomitized mudstones and wackestones grading upward into sebkha-salina evaporites. Mission Canyon oil production is localized on the north and northeast side of the structure. Maps of porosity pinch-outs and permeability barriers defined from core data, superimposed upon the Mission Canyon structure, show that most of the oil cannot be trapped by stratigraphic facies change. Southwest-trending, updip porosity pinch-outs cross the north-plunging structural axis at an angle so low that hydrocarbons would leak out to the southwest under hydrostatic conditions. Downdip hydrodynamic flow to the northeast provides the critical trapping component. Regional maps of apparent formation water resistivity and water salinity show a region of fresher water south and southwest of the field. A regional potentiometric map constructed using Horner-plot extrapolated shut-in pressure data indicates a head gradient of about 20 ft/mi (4 m/km) to the northeast at Elkhorn Ranch field. This gradient corresponds to a calculated water-oil tilt of about 50 ft/mi (20 m/km). Observed tilt of the oil accumulation is actually about 25 ft/mi (5 m/km) to the northeast. This discrepancy might be the result of the field having not yet reached equilibrium with the invading water.

  12. Accelerated Stress Testing, Qualification Testing, HAST, Field...

    Office of Environmental Management (EM)

    stress tests beyond the qualification test levels, which are necessary to predict PV module wear-out. The commercial success of PVs is ultimately based on the long-term...

  13. How DARHT Works - the World's Most Powerful X-ray Machine

    ScienceCinema (OSTI)

    None

    2014-06-25T23:59:59.000Z

    The Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory is an essential scientific tool that supports Stockpile Stewardship at the Laboratory. The World's most powerful x-ray machine, it's used to take high-speed images of mock nuclear devices - data that is used to confirm and modify advanced computer codes in assuring the safety, security, and effectiveness of the U.S. nuclear deterrent.

  14. How DARHT Works - the World's Most Powerful X-ray Machine

    SciTech Connect (OSTI)

    None

    2011-11-06T23:59:59.000Z

    The Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory is an essential scientific tool that supports Stockpile Stewardship at the Laboratory. The World's most powerful x-ray machine, it's used to take high-speed images of mock nuclear devices - data that is used to confirm and modify advanced computer codes in assuring the safety, security, and effectiveness of the U.S. nuclear deterrent.

  15. RMOTC - Testing - Geothermal

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

    Geothermal Testing Notice: As of July 1st, 2014, Testing at RMOTC has officially completed. We would like to thank all of our testing partners and everyone who helped make the...

  16. Test Herrera Report Template

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

    development are described in detail in the following section. The model was run in six test sites: Test Site 1 is along the Cowlitz River (Segment 3); Test Site 2 includes the...

  17. ZiaTest

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

    ZiaTest ZiaTest Description This test executes a new proposed standard benchmark method for MPI startup that is intended to provide a realistic assessment of both launch and wireup...

  18. Directed random testing

    E-Print Network [OSTI]

    Pacheco, Carlos, Ph.D. Massachusetts Institute of Technology

    2009-01-01T23:59:59.000Z

    Random testing can quickly generate many tests, is easy to implement, scales to large software applications, and reveals software errors. But it tends to generate many tests that are illegal or that exercise the same parts ...

  19. Hydrodynamic equilibrium of a static star in the presence of a cosmological constant in 2 + 1 dimensions

    E-Print Network [OSTI]

    Alberto A. Garcia Diaz

    2014-12-17T23:59:59.000Z

    Under the hydrodynamic equilibrium Buchdahl's conditions on the behavior of the density and the pressure, for regular fluid static circularly symmetric star in (2 + 1) dimensions in the presence of a cosmological constant, is established that there are no bounds from below on the pressure and also on the mass, except for their positiveness. The metric for a constant density distribution is derived and its matching with the external static solution with a negative cosmological constant is accomplished. Some mistakes of previous works on the topic are pointed out.

  20. Stellar evolution of low and intermediate-mass stars. IV. Hydrodynamically-based overshoot and nucleosynthesis in AGB stars

    E-Print Network [OSTI]

    F. Herwig; T. Blöcker; D. Schönberner; M. El Eid

    1997-06-12T23:59:59.000Z

    The focus of this study is on the treatment of those stellar regions immediately adjacent to convective zones. The results of hydrodynamical simulations by Freytag et al. (1996, A&A313,497) show that the motion of convective elements extends well beyond the boundary of the convectively unstable region. We have applied their parametrized description of the corresponding velocities to the treatment of overshoot in stellar evolution calculations up to the AGB (Pop.I, M_zams=3M_sun).

  1. LANSCE | Materials Test Station

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

    Research Facility Training Office Contact Administrative nav background Materials Test Station dotline Testing New Reactor Fuels that Reduce Radioactive Waste Mission Used...

  2. Vendor System Vulnerability Testing Test Plan

    SciTech Connect (OSTI)

    James R. Davidson

    2005-01-01T23:59:59.000Z

    The Idaho National Laboratory (INL) prepared this generic test plan to provide clients (vendors, end users, program sponsors, etc.) with a sense of the scope and depth of vulnerability testing performed at the INL’s Supervisory Control and Data Acquisition (SCADA) Test Bed and to serve as an example of such a plan. Although this test plan specifically addresses vulnerability testing of systems applied to the energy sector (electric/power transmission and distribution and oil and gas systems), it is generic enough to be applied to control systems used in other critical infrastructures such as the transportation sector, water/waste water sector, or hazardous chemical production facilities. The SCADA Test Bed is established at the INL as a testing environment to evaluate the security vulnerabilities of SCADA systems, energy management systems (EMS), and distributed control systems. It now supports multiple programs sponsored by the U.S. Department of Energy, the U.S. Department of Homeland Security, other government agencies, and private sector clients. This particular test plan applies to testing conducted on a SCADA/EMS provided by a vendor. Before performing detailed vulnerability testing of a SCADA/EMS, an as delivered baseline examination of the system is conducted, to establish a starting point for all-subsequent testing. The series of baseline tests document factory delivered defaults, system configuration, and potential configuration changes to aid in the development of a security plan for in depth vulnerability testing. The baseline test document is provided to the System Provider,a who evaluates the baseline report and provides recommendations to the system configuration to enhance the security profile of the baseline system. Vulnerability testing is then conducted at the SCADA Test Bed, which provides an in-depth security analysis of the Vendor’s system.b a. The term System Provider replaces the name of the company/organization providing the system being evaluated. This can be the system manufacturer, a system user, or a third party organization such as a government agency. b. The term Vendor (or Vendor’s) System replaces the name of the specific SCADA/EMS being tested.

  3. Hydrodynamic and Sediment Dynamics Modeling Primary Investigator: David Schwab -NOAA GLERL

    E-Print Network [OSTI]

    is concerned with developing and testing a numerical model for predicting resuspension, transport will lead to better understanding of the response of the Great Lakes ecosystem to the impact of natural

  4. Dynamometer Testing (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2010-11-01T23:59:59.000Z

    This fact sheet describes the dynamometer and its testing capabilities at the National Wind Technology Center.

  5. Comparison of Hydrodynamic Load Predictions Between Engineering Models and Computational Fluid Dynamics for the OC4-DeepCwind Semi-Submersible: Preprint

    SciTech Connect (OSTI)

    Benitz, M. A.; Schmidt, D. P.; Lackner, M. A.; Stewart, G. M.; Jonkman, J.; Robertson, A.

    2014-09-01T23:59:59.000Z

    Hydrodynamic loads on the platforms of floating offshore wind turbines are often predicted with computer-aided engineering tools that employ Morison's equation and/or potential-flow theory. This work compares results from one such tool, FAST, NREL's wind turbine computer-aided engineering tool, and the computational fluid dynamics package, OpenFOAM, for the OC4-DeepCwind semi-submersible analyzed in the International Energy Agency Wind Task 30 project. Load predictions from HydroDyn, the offshore hydrodynamics module of FAST, are compared with high-fidelity results from OpenFOAM. HydroDyn uses a combination of Morison's equations and potential flow to predict the hydrodynamic forces on the structure. The implications of the assumptions in HydroDyn are evaluated based on this code-to-code comparison.

  6. DIANA: A multi-phase, multi-component hydrodynamic model for the analysis of severe accidents in heavy water reactors with multiple-tube assemblies

    SciTech Connect (OSTI)

    Tentner, A.M.

    1994-03-01T23:59:59.000Z

    A detailed hydrodynamic fuel relocation model has been developed for the analysis of severe accidents in Heavy Water Reactors with multiple-tube Assemblies. This model describes the Fuel Disruption and Relocation inside a nuclear fuel assembly and is designated by the acronym DIANA. DIANA solves the transient hydrodynamic equations for all the moving materials in the core and treats all the relevant flow regimes. The numerical solution techniques and some of the physical models included in DIANA have been developed taking advantage of the extensive experience accumulated in the development and validation of the LEVITATE (1) fuel relocation model of SAS4A [2, 3]. The model is designed to handle the fuel and cladding relocation in both voided and partially voided channels. It is able to treat a wide range of thermal/ hydraulic/neutronic conditions and the presence of various flow regimes at different axial locations within the same hydrodynamic channel.

  7. The pre-merger impact velocity of the binary cluster A1750 from X-ray, lensing, and hydrodynamical simulations

    SciTech Connect (OSTI)

    Molnar, Sandor M. [Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, Taipei 10617, Taiwan (China); Chiu, I-Non Tim [Department of Physics, Ludwig-Maximilians University, Scheinerstr 1, D-81679 Munich (Germany); Broadhurst, Tom [Department of Theoretical Physics, University of the Basque Country, E-48080 Bilbao (Spain); Stadel, Joachim G., E-mail: sandor@phys.ntu.edu.tw [Institute for Theoretical Physics, University of Zurich, 8057 Zurich (Switzerland)

    2013-12-10T23:59:59.000Z

    Since the discovery of the 'Bullet Cluster', several similar cases have been uncovered that suggest relative velocities well beyond the tail of high speed collisions predicted by the concordance ?CDM model. However, quantifying such post-merger events with hydrodynamical models requires a wide coverage of possible initial conditions. Here, we show that it is simpler to interpret pre-merger cases, such as A1750, where the gas between the colliding clusters is modestly affected, so that the initial conditions are clear. We analyze publicly available Chandra data confirming a significant increase in the projected X-ray temperature between the two cluster centers in A1750 consistent with our expectations for a merging cluster. We model this system with a self-consistent hydrodynamical simulation of dark matter and gas using the FLASH code. Our simulations reproduce well the X-ray data and the measured redshift difference between the two clusters in the phase before the first core passage viewed at an intermediate projection angle. The deprojected initial relative velocity derived using our model is 1460 km s{sup –1}, which is considerably higher than the predicted mean impact velocity for simulated massive haloes derived by recent ?CDM cosmological simulations, but is within the allowed range. Our simulations demonstrate that such systems can be identified using a multi-wavelength approach and numerical simulations, for which the statistical distribution of relative impact velocities may provide a definitive examination of a broad range of dark matter scenarios.

  8. Prediction of hydrodynamic properties of mixed-particle systems and theoretical analysis of loop pressure profile in a CFB unit

    SciTech Connect (OSTI)

    Das, M.; Meikap, B.C.; Saha, R.K. [Indian Institute for Technology, Kharagpur (India). Dept. for Chemical Engineering

    2008-07-15T23:59:59.000Z

    The hydrodynamic behaviors of mixed system of particles were investigated in a circulating fluidized bed (CFB) unit consisting of fast column (riser) with an inner diameter of 0.1016 m and a height of 5.62 m. Particle mixtures containing a Geldart group-A-like fluid catalytic cracking (FCC) catalyst with group-B-like sand and iron ore with coal were used to study the hydrodynamic features including static pressure, voidage, and loop pressure profile. The mixed system consisting of FCC catalyst and sand contained 20, 50, and 80 mass % sand, and the coal-iron ore mixture contained 80 mass % coal. The superficial air velocity ranged between 2.01 and 4.681 m/s, and the corresponding mass fluxes were 12.5-50 kg/(m{sup 2} s). A comparison of the available experimental values for static pressure profiles at different operating conditions for mixed-particle systems shows good agreement with those predicted from the single-particle systems. Using experimental data on the loop pressure balance, a simplified theoretical analysis was performed to predict the pressure profile in the CFB loop. The deviations between the two sets of values are within reasonable limits of accuracy.

  9. Exploration of the Transition from the Hydrodynamic-like to the Strongly Kinetic Regime in Shock-Driven Implosions

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

    Rosenberg, M. J.; Rinderknecht, H. G.; Hoffman, N. M.; Amendt, P. A.; Atzeni, S.; Zylstra, A. B.; Li, C. K.; Seguin, F. H.; Sio, H.; Johnson, M. Gatu; et al

    2014-05-01T23:59:59.000Z

    Clear evidence of the transition from hydrodynamiclike to strongly kinetic shock-driven implosions is, for the first time, revealed and quantitatively assessed. Implosions with a range of initial equimolar D3He gas densities show that as the density is decreased, hydrodynamic simulations strongly diverge from and increasingly over-predict the observed nuclear yields, from a factor of ~2 at 3.1 mg/cm3 to a factor of 100 at 0.14 mg/cm3. (The corresponding Knudsen number, the ratio of ion mean-free path to minimum shell radius, varied from 0.3 to 9; similarly, the ratio of fusion burn duration to ion diffusion time, another figure of meritmore »of kinetic effects, varied from 0.3 to 14.) This result is shown to be unrelated to the effects of hydrodynamic mix. As a first step to garner insight into this transition, a reduced ion kinetic (RIK) model that includes gradient-diffusion and loss-term approximations to several transport processes was implemented within the framework of a one-dimensional radiation-transport code. After empirical calibration, the RIK simulations reproduce the observed yield trends, largely as a result of ion diffusion and the depletion of the reacting tail ions.« less

  10. Exploration of the Transition from the Hydrodynamic-like to the Strongly Kinetic Regime in Shock-Driven Implosions

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

    Rosenberg, M. J. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Plasma Science and Fusion Center; Rinderknecht, H. G. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Plasma Science and Fusion Center; Hoffman, N. M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Amendt, P. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Atzeni, S. [Univ. of Roma, Roma (Italy). Dipartimento SBAI; Zylstra, A. B. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Plasma Science and Fusion Center; Li, C. K. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Plasma Science and Fusion Center; Seguin, F. H. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Plasma Science and Fusion Center; Sio, H. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Plasma Science and Fusion Center; Johnson, M. Gatu [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Plasma Science and Fusion Center; Frenje, J. A. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Plasma Science and Fusion Center; Petrasso, R. D. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Plasma Science and Fusion Center; Glebov, V. Yu. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Stoeckl, C. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Seka, W. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Marshall, F. J. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Delettrez, J. A. [Univ. of Rochester, NY (United States). Lab. for Laser EnergeticsUniv. of Rochester, NY (United States). Lab. for Laser Energetics; Sangster, T. C. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Betti, R. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Goncharov, V. N. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Meyerhofer, D. D. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Skupsky, S. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Bellei, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pino, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wilks, S. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kagan, G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Molvig, K. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Nikroo, A. [General Atomics, San Diego, CA (United States)

    2014-05-01T23:59:59.000Z

    Clear evidence of the transition from hydrodynamiclike to strongly kinetic shock-driven implosions is, for the first time, revealed and quantitatively assessed. Implosions with a range of initial equimolar D3He gas densities show that as the density is decreased, hydrodynamic simulations strongly diverge from and increasingly over-predict the observed nuclear yields, from a factor of ~2 at 3.1 mg/cm3 to a factor of 100 at 0.14 mg/cm3. (The corresponding Knudsen number, the ratio of ion mean-free path to minimum shell radius, varied from 0.3 to 9; similarly, the ratio of fusion burn duration to ion diffusion time, another figure of merit of kinetic effects, varied from 0.3 to 14.) This result is shown to be unrelated to the effects of hydrodynamic mix. As a first step to garner insight into this transition, a reduced ion kinetic (RIK) model that includes gradient-diffusion and loss-term approximations to several transport processes was implemented within the framework of a one-dimensional radiation-transport code. After empirical calibration, the RIK simulations reproduce the observed yield trends, largely as a result of ion diffusion and the depletion of the reacting tail ions.

  11. An Empirical Study on Ultrasonic Testing in Lieu of Radiography for Nuclear Power Plants

    SciTech Connect (OSTI)

    Moran, Traci L.; Pardini, Allan F.; Ramuhalli, Pradeep; Prowant, Matthew S.; Mathews, Royce

    2012-09-01T23:59:59.000Z

    Research is being conducted for the U.S. Nuclear Regulatory Commission (NRC) at the Pacific Northwest National Laboratory (PNNL) to assess the capability, effectiveness, and reliability of ultrasonic testing (UT) as a replacement method for radiographic testing (RT) for inspecting nuclear power plant (NPP) components. A primary objective of this work is to evaluate UT techniques to assess their ability to detect, locate, size, and characterize fabrication flaws in typical NPP weldments. This particular study focused on the evaluation of four carbon steel pipe-to-pipe welds on specimens that ranged in thicknesses from 19.05 mm (0.75 in.) to 27.8 mm (1.094 in.) and were 355.6 mm (14.0 in.) or 406.4 mm (16.0 in.) in diameter. The pipe welds contained both implanted (intentional) fabrication flaws as well as bonus (unintentional) flaws throughout the entire thickness of the weld and the adjacent base material. The fabrication flaws were a combination of planar and volumetric flaw types, including incomplete fusion, incomplete penetration, cracks, porosity, and slag inclusions. The examinations were conducted using phased-array UT (PA UT) techniques applied primarily for detection and length sizing of the flaws. Radiographic examinations were also conducted on the specimens with RT detection and length sizing results being used to establish true state. This paper will discuss the comparison of UT and RT (true state) detection results conducted to date along with a discussion on the technical gaps that need to be addressed before these methods can be used interchangeably for repair and replacement activities for NPP components.

  12. Solderability test system

    DOE Patents [OSTI]

    Yost, F.; Hosking, F.M.; Jellison, J.L.; Short, B.; Giversen, T.; Reed, J.R.

    1998-10-27T23:59:59.000Z

    A new test method to quantify capillary flow solderability on a printed wiring board surface finish. The test is based on solder flow from a pad onto narrow strips or lines. A test procedure and video image analysis technique were developed for conducting the test and evaluating the data. Feasibility tests revealed that the wetted distance was sensitive to the ratio of pad radius to line width (l/r), solder volume, and flux predry time. 11 figs.

  13. Solderability test system

    DOE Patents [OSTI]

    Yost, Fred (Cedar Crest, NM); Hosking, Floyd M. (Albuquerque, NM); Jellison, James L. (Albuquerque, NM); Short, Bruce (Beverly, MA); Giversen, Terri (Beverly, MA); Reed, Jimmy R. (Austin, TX)

    1998-01-01T23:59:59.000Z

    A new test method to quantify capillary flow solderability on a printed wiring board surface finish. The test is based on solder flow from a pad onto narrow strips or lines. A test procedure and video image analysis technique were developed for conducting the test and evaluating the data. Feasibility tests revealed that the wetted distance was sensitive to the ratio of pad radius to line width (l/r), solder volume, and flux predry time.

  14. Modeling the Structural Response from a Propagating High Explosive Using Smooth Particle Hydrodynamics

    SciTech Connect (OSTI)

    Margraf, J

    2012-06-12T23:59:59.000Z

    This report primarily concerns the use of two massively parallel finite element codes originally written and maintained at Lawrence Livermore National Laboratory. ALE3D is an explicit hydrodynamics code commonly employed to simulate wave propagation from high energy scenarios and the resulting interaction with nearby structures. This coupled response ensures that a structure is accurately applied with a blast loading varying both in space and time. Figure 1 illustrates the radial outward propagation of a pressure wave due to a center detonated spherical explosive originating from the lower left. The radial symmetry seen in this scenario is lost when instead a cylindrocal charge is detonated. Figure 2 indicates that a stronger, faster traveling pressure wave occurs in the direction of the normal axis to the cylinder. The ALE3D name is derived because of the use of arbitrary-Lagrange-Eulerian elements in which the mesh is allowed to advect; a process through which the mesh is modified to alleviate tanlging and general mesh distortion often cuased by high energy scenarios. The counterpart to an advecting element is a Lagrange element, whose mesh moves with the material. Ideally all structural components are kept Lagrange as long as possible to preserve accuracy of material variables and minimize advection related errors. Advection leads to mixed zoning, so using structural Lagrange elements also improves the visualization when post processing the results. A simplified representation of the advection process is shown in Figure 3. First the mesh is distorted due to material motion during the Lagrange step. The mesh is then shifted to an idealized and less distorted state to prevent irregular zones caused by the Lagrange motion. Lastly, the state variables are remapped to the elements of the newly constructed mesh. Note that Figure 3 represents a purely Eulerian mesh relaxation because the mesh is relocated back to the pre-Lagrange position. This is the case when the material flows through a still mesh. This is not typically done in an ALE3D analysis, especially if Lagrange elements exist. Deforming Lagrange elements would certainly tangle with a Eulerian mesh eventually. The best method in this case is to have an advecting mesh positioned as some relaxed version of the pre and post Lagrange step; this gives the best opportunity of modeling a high energy event with a combination of Lagrange and ALE elements. Dyne3D is another explicit dynamic analysis code, ParaDyn being the parallel version. ParaDyn is used for predicting the transient response of three dimensional structures using Lagrangian solid mechanics. Large deformation and mesh tangling is often resolved through the use of an element deletion scheme. This is useful to accommodate component failure, but if it is done purely as a means to preserve a useful mesh it can lead to problems because it does not maintain continuity of the material bulk response. Whatever medium exists between structural components is typically not modeled in ParaDyn. Instead, a structure either has a known loading profile applied or given initial conditions. The many included contact algorithms can calculate the loading response of materials if and when they collide. A recent implementation of an SPH module in which failed or deleted material nodes are converted to independent particles is currently being utilized for a variety of spall related problems and high velocity impact scenarios. Figure 4 shows an example of a projectile, given an initial velocity, and how it fails the first plate which generates SPH particles which then interact with and damage the second plate.

  15. Check for peroxides every 6 months. opened test 1 test 2 test 3

    E-Print Network [OSTI]

    Pawlowski, Wojtek

    Check for peroxides every 6 months. opened test 1 test 2 test 3 date initials Check for peroxides every 6 months. opened test 1 test 2 test 3 date initials Check for peroxides every 6 months. Test strips can be obtained from EH&S, 5-8200 opened test 1 test 2 test 3 date initials Check for peroxides

  16. Automatic Test Factoring for Java

    E-Print Network [OSTI]

    Saff, David

    2005-06-08T23:59:59.000Z

    Test factoring creates fast, focused unit tests from slow system-widetests; each new unit test exercises only a subset of the functionalityexercised by the system test. Augmenting a test suite with factoredunit tests ...

  17. Entry/Exit Port testing, test report

    SciTech Connect (OSTI)

    Winkelman, R.H.

    1993-05-01T23:59:59.000Z

    The Waste Receiving and Processing Module I (WRAP-1) facility must have the ability to allow 55-gallon drums to enter and exit glovebox enclosures. An Entry/Exit Port (Appendix 1, Figure 1), designed by United Engineers and Constructors (UE&C), is one method chosen for drum transfer. The Entry/Exit Port is to be used for entry of 55-gallon drums into both process entry gloveboxes, exit of 55-gallon drum waste pucks from the low-level waste (LLW) glovebox, and loadout of waste from the restricted waste management glovebox. The Entry/Exit Port relies on capture velocity air flow and a neoprene seal to provide alpha confinement when the Port is in the open and closed positions, respectively. Since the glovebox is in a slight vacuum, air flow is directed into the glovebox through the space between the overpack drum and glovebox floor. The air flow is to direct any airborne contamination into the glovebox. A neoprene seal is used to seal the Port door to the glovebox floor, thus maintaining confinement in the closed position. Entry/Exit Port testing took place February 17, 1993, through April 14, 1993, in the 305 building of Westinghouse Hanford Company. Testing was performed in accordance with the Entry/Exit Port Testing Test Plan, document number WHC-SD-WO26-TP-005. A prototype Entry/Exit Port built at the Hanford Site was tested using fluorescent paint pigment and smoke candles as simulant contaminants. This test report is an interim test report. Further developmental testing is required to test modifications made to the Port as the original design of the Port did not provide complete confinement during all stages of operation.

  18. I/O Test

    E-Print Network [OSTI]

    Beeler, Michael

    1967-10-01T23:59:59.000Z

    IO TEST is intended as a hardware testing and debugging aid for use with the PDP-6 and its associated input multiplexer (analog to digital converter) and output multiplexer (digital to analog converter). While all characters ...

  19. MA 266 Practice Test

    E-Print Network [OSTI]

    2015-02-26T23:59:59.000Z

    Test 1: March 4, 2015. INSTRUCTIONS in the Test. 1. Do not open this exam booklet until told to do so. 2. There are 6 or 7 problems - one per page. 3. Show all ...

  20. Practice test 2

    E-Print Network [OSTI]

    2015-04-12T23:59:59.000Z

    Spring 2015. Test 2: April 15, 2015. INSTRUCTIONS in the Test. 1. Do not open this exam booklet until told to do so. 2. There are 6 or 7 problems - one per page.