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in subjects: "Compressibility"

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Taylor Instability in Shock Acceleration of Compressible Fluids

The initial growth of irregularities on an interface between two compressible fluids is studied for impulsive (i.e., shock) acceleration. It was found that the ultimate rate of growth is roughly the same as that given by the incompressible theory, if the initial compression of the irregularities and of the fluids is taken into account.

Date: July 1954

Creator: Richtmyer, Robert D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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High temperature properties of nuclear reactor coolants and thermodynamic power cycle working fluids. Technical progress report, October 1, 1974--September 30, 1975. [LMFBR]

Vapor pressure measurements on sodium by the pressure tube method are reported up to 3,267 lbs/sq. in. absolute and 4340 deg Rankine. A picnometer-type apparatus for measuring the isothermal compressibility of liquid sodium has been completed. It was tested with water, giving reasonably good checks of steam table values. This apparatus is expected to be able to also provide P-V-T data on sodium up to some 3000/sup 0/F, and on cesium to the critical region. The program on properties of mercury v… more

Date: August 1, 1975

Creator: Bonilla, C. F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Shock compression of pyrolytic, ceylon natural, and a hot-pressed synthetic graphite to 120 GPa

Recent improvements have made the two-stage, light-gas gun at Lawrence Livermore Laboratory into a dependable source of very energetic planar shocks. Also, the inclined-prism technique has proved useful in observing anomalous behavior of materials, especially at low pressure. The availability of these improved techniques presented an opportunity to re-examine the low pressure, shock-compression characteristics for graphite and, in a search for an additional transformation, to extend some of the… more

Date: June 6, 1977

Creator: Gust, W. H. & Young, D. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Studies of californium metal at high pressure by x-ray diffraction

The behavior of the crystal structure of californium metal under various pressures up to 140 kbars has been studied by use of a diamond-anvil type of miniature x-ray diffraction camera. Ten-microgram samples were encapsulated in aluminum foil, which also served as an internal standard for pressure determination. The phase transitions in cerium metal were produced and identified as a test of the apparatus and technique. Californium metal samples in the low-density face-centered cubic form (a/sub… more

Date: January 1, 1977

Creator: Burns, J. H. & Peterson, J. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Properties of Fluid Deuterium under Double-Shock Compression to Several Mbar

The compressibility of fluid deuterium up to several Mbar has been probed using laser-driven shock waves reflected from a quartz anvil. Combining high-precision ({approx} 1 %) shock velocity measurements with the double-shock technique, where differences in equation of state (EOS) models are magnified, has allowed us to accurately discriminate between various theoretical predictions. Our data are consistent with EOS models that show approximately fourfold compression on the principal Hugoniot f… more

Date: February 3, 2004

Creator: Vianello, E; Celliers, P M; Hicks, D G; Boehly, T R; Collins, T B; Moon, S J et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Effect of Initial Conditions on Compressible Rayleigh-Taylor Instability and Transition to Turbulence

Perturbations on an interface driven by a strong blast wave grow in time due to a combination of Rayleigh-Taylor, Richtmyer-Meshkov, and decompression effects. In this paper, we present the first results from a computational study of such a system under drive conditions to be attainable on the National Ignition Facility. Using the multiphysics, AMR, higher order Godunov Eulerian hydrocode, Raptor, we consider the late nonlinear instability evolution for multiple amplitude and phase realizations… more

Date: January 7, 2004

Creator: Miles, A R; Edwards, M & Greenough, J A

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Basic physics of one-dimensional metals. [Lectures, electron gas]

Largely nonmathematical qualitative lectures are given on the basic physics of nearly one-dimensional conductors. The main emphasis is placed on the properties of a purely one-dimensional electron gas. The effects of a real system having interchain coupling, impurities, a compressible lattice, lattice distortions and phonon anomalies are discussed. (JFP)

Date: January 1, 1976

Creator: Emery, V. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The Effect of Initial Conditions on the Nonlinear Evolution of Perturbed Interfaces Driven by Strong Blast Waves

In core-collapse supernovae, strong blast waves drive interfaces susceptible to Rayleigh-Taylor (RT), Richtmyer-Meshkov (RM), and Kelvin-Helmholtz (KH) instabilities. In addition, perturbation growth can result from material expansion in large-scale velocity gradients behind the shock front. Laser-driven experiments are designed to produce a strongly shocked interface whose evolution is a scaled version of the unstable hydrogen-helium interface in core-collapse supernovae such as SN 1987A. The … more

Date: April 27, 2004

Creator: Miles, A

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

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The effect of a short wavelength mode on the evolution of a long wavelength perturbation driven by a strong blast wave

Shock-accelerated material interfaces are potentially unstable to both the Richtmyer-Meshkov and Rayleigh-Taylor instabilities. Shear that develops along with these instabilities in turn drives the Kelvin-Helmholtz instability. When driven by strong shocks, the evolution and interaction of these instabilities is further complicated by compressibility effects. In this paper, we present a computational study of the formation of jets at strongly driven hydrodynamically unstable interfaces, and the… more

Date: March 16, 2004

Creator: Miles, A. R.; Edwards, M.; Blue, B.; Hansen, J. F.; Robey, H. F.; Drake, R. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Compressibility Corrections to Closure Approximations for Turbulent Flow Simulations

We summarize some modifications to the usual closure approximations for statistical models of turbulence that are necessary for use with compressible fluids at all Mach numbers. We concentrate here on the gradient-flu approximation for the turbulent heat flux, on the buoyancy production of turbulence kinetic energy, and on a modification of the Smagorinsky model to include buoyancy. In all cases, there are pressure gradient terms that do not appear in the incompressible models and are usually o… more

Date: February 1, 2003

Creator: Cloutman, L D

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Effects of Initial Conditions on Compressible Mixing in Supernova-Relevant Laboratory Experiments

Date: April 30, 2004

Creator: Miles, A R; Edwards, M & Greenough, J

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A New Lifshitz Transition and the Equation of State of Osmium

We have measured the equation of state (EoS) of osmium to 75 GPa under hydrostatic conditions at room temperature using angle dispersive x-ray diffraction. A least-squares fit of the data using a third order Birch-Murnaghan EoS yields K{sub 0} = 411 {+-} 6 GPa and K'{sub 0} = 4.0 {+-} 0.2, showing osmium is in fact more compressible than diamond. Most importantly, we have documented an anomaly in the compressibility at 20.3 GPa associated with a large discontinuity in the first pressure derivat… more

Date: November 5, 2003

Creator: Occelli, F.; Aracne, C. M.; Teter, D. M.; Hanfland, M.; Canny, B.; Couzinet, B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Effect of Initial Conditions on 2D Rayleigh-Taylor Instability and Transition to Turbulence in Planar Blast-wave-driven Systems

Date: March 26, 2004

Creator: Miles, A R; Edwards, M J & Greenough, J A

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Development of a dual-porosity model for vapor-dominated fractured geothermal reservoirs using a semi-analytical fracture/matrix interaction term

A new type of dual-porosity model is being developed to simulate two-phase flow processes in fractured geothermal reservoirs. At this time it is assumed that the liquid phase in the matrix blocks remains immobile. By utilizing the effective compressibility of a two-phase water/steam mixture in a porous rock, flow within the matrix blocks can be modeled by a single diffusion equation. This equation in turn is replaced by a non-linear ordinary differential equation that utilizes the mean pressure… more

Date: February 1, 1993

Creator: Zimmerman, R. W.; Hadgu, T. & Bodvarsson, G. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Shock compression properties of silicon carbide

An investigation of the shock compression and release properties of silicon carbide ceramic has been performed. A series of planar impact experiments has been completed in which stationary target discs of ceramic were struck by plates of either similar ceramic or other appropriate material at velocities up to 2.2 km/s with a propellant gun facility. The particle velocity history at the interface between the back of the target ceramic and a lithium-fluoride window material was measured with lase… more

Date: July 1, 1993

Creator: Grady, D. E. & Kipp, M. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Compressed natural gas measurement issues

The Natural Gas Vehicle Coalition`s Measurement and Metering Task Group (MMTG) was established on July 1st, 1992 to develop suggested revisions to National Institute of Standards & Technology (NIST) Handbook 44-1992 (Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices) and NIST Handbook 130-1991 (Uniform Laws & Regulations). Specifically, the suggested revisions will address the sale and measurement of compressed natural gas when sold as a motor vehic… more

Date: December 31, 1993

Creator: Blazek, C. F.; Kinast, J. A. & Freeman, P. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Physical and thermal properties and leaching characteristics of a beneficiated eastern oil shale hydroretorted in the PFH process

The preferred feedstocks for the Institute of Gas Technology`s (IGT) Pressurized Fluidized-Bed Hydroretorting (PFH) process are beneficiated Eastern US oil shales. After hydroretorting, the beneficiated shale is combusted to generate process and export power. Before hydroretorting and after combustion the shale will be stored in large embankments. The design and characteristics of these embankments depends on the physical, thermal, and leaching properties of the raw and spent shales. IGT and th… more

Date: December 31, 1992

Creator: Mensinger, M. C. & Budiman, J. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Physical characterization of magmatic liquids. Final report, August 15, 1985--February 28, 1991

This report describes a research project that was conducted from August 15, 1985 to February 28, 1992. The project was based on the ultrasonic studies of natural and synthetic silicate melts, and the study of Brillouin scattering of synthetic silicates and oxides. Measurements of the compressional wave velocity and attenuation can be established using the ultrasonic methods. Temperature dependences of silicates can be established by the Brillouin scattering. (MB)

Date: June 5, 1992

Creator: Manghnani, M. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Mercury-free PVT apparatus for thermophysical property analyses of hydrocarbon reservoir fluids. Final report, August 16, 1990--July 31, 1992

Typical reservoir fluid analyses of complex, multicomponent hydrocarbon mixtures include the volumetric properties, isothermal compressibility, thermal expansivity, equilibrium ratios, saturation pressure, viscosities, etc. These parameters are collectively referred to as PVT properties, an acronym for the primary state variables; pressure, volume, and temperature. The reservoir engineer incorporates this information together with the porous media description in performing material balance calc… more

Date: August 31, 1992

Creator: Lansangan, R. M. & Lievois, J. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Characterization of double-shell slurry feed grout produced in a pilot-scale test. Hanford Grout Technology Program

Current plans for disposal of the low-level fraction of selected double-shell tank (DST) wastes at Hanford, Washington include grouting. Grout disposal in this context is the process of mixing low-level liquid waste with cementitious powders. and pumping the resultant slurry to near-surface, underground concrete vaults. Once the slurry is in the vaults. the hydration reactions that occur result in the formation of a highly impermeable solid product that binds and encapsulates the radioactive an… more

Date: December 1, 1992

Creator: Lokken, R. O.; Martin, P. F. C. & Shade, J. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Waste-Form Development Program. Annual progress report, October 1981-September 1982

Low-level wastes (LLW) at nuclear facilities have traditionally been solidified using portland cement (with and without additives). Urea-formaldehyde has been used for LLW solidification while bitumen (asphalt) and thermosetting polymers will be applied to domestic wastes in the near future. Operational difficulties have been observed with each of these solidification agents. Such difficulties include incompatibility with waste constitutents inhibiting solidification, premature setting, free st… more

Date: September 1, 1982

Creator: Neilson, R.M. Jr. & Colombo, P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Geotechnical aspects of subsurface seabed disposal of high level radioactive wastes. Annual progress report, January--December 1977

The status of the following major studies is reported: geotechnical properties of deep sea clays; experimental water migration studies;laboratory hole closure experiments; and in-site heat transfer experiments. (LK)

Date: May 1, 1978

Creator: Silva, A.J. & Calnan, D,I.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Nuclear equation of state studied with high-energy heavy ions

The current knowledge and theoretical speculations concerning the nuclear equation of state is discussed. Conventional relativistic nuclear fluid dynamics, which is based on the assumption that the nucleon mean free path is zero and consequently neglects the interpenetration of the target and projectile upon contact, is also discussed. Results of such calculations performed for three different equations of state are compared with experimental data for both all impact parameters and central coll… more

Date: January 1, 1981

Creator: Nix, J. R. & Strottman, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Physical processes of subsidence in geothermal reservoirs

The objectives of this project were to acquire core and fluid from producing geothermal reservoirs (East Mesa, United States, and Cerro Prieto, Mexico); to test specimens of this core for their short-term and long-term (creep) compaction response; and to develop a compaction constitutive model that would allow future analysis of reservoir compaction and a surface subsidence. A total of approximately two hundred feet of core was obtained from eleven wells in the two geothermal fields. Depths and… more

Date: June 1, 1982

Creator: Schatz, J. F.

Item Type: Report

Partner: UNT Libraries Government Documents Department