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Sample records for processes isentropic

  1. Analysis of isentropic potential vorticities for the relationship between stratospheric polar vortex and the cooling process in China

    NASA Astrophysics Data System (ADS)

    Lu, C.

    2015-12-01

    We analyze the relationships between stratospheric polar vortex anomalies and cooling events in eastern China using isentropic reanalysis data from the European Center for Medium-Range Weather Forecasts. Daily mean data from 2000 to 2011 are used to explore the effective stratospheric signals. First, diagnoses of the 2009/2010 winter show that after the stratospheric sudden warming (SSW) of the Atlantic-East Asian (AEA) pattern, the stratospheric high isentropic potential vorticity(IPV) center derived from the split polar vortex will move to the northeast of the Eurasian continent. The air mass, accompanied by some southward and eastward movements and characterized by high IPV values, will be stretched vertically, leading to apparent reinforcements of the positive vorticity and the development of a cold vortex system in the troposphere. The northerly wind on the western side of the cold vortex can transport cold air southward and downward, resulting in this distinct cooling process in eastern China. Secondly, the Empirical Orthogonal Function analyses of IPV anomalies on the 430 K isentropic surface during 2000-2011 winters indicate that the IPV distribution and time series of the first mode are able to represent the polar vortex variation features, which significantly influence cold-air activity in eastern China, especially in the AEA-type SSW winter. When the time series increases significantly, the polar vortex will be split and the high-IPV center will move to the northeast of the Eurasian continent with downward and southward developments, inducing obvious cooling in eastern China. Moreover, all the four times SSW events of AEA pattern from 2000 to 2011 are reflected in the first time series, and after the strong polar vortex disturbances, cooling processes of different intensities are observed in eastern China. The cooling can sustain at least one week. For this reason the first time series can be used as an available index of polar vortex oscillation and has

  2. Numerical investigations with a hybrid isentropic-sigma model. I - Normal-mode characteristics. II - The inclusion of moist processes

    NASA Technical Reports Server (NTRS)

    Pierce, R. B.; Johnson, Donald R.; Reames, Fred M.; Zapotocny, Tom H.; Wolf, Bart J.

    1991-01-01

    The normal-mode characteristics of baroclinically amplifying disturbances were numerically investigated in a series of adiabatic simulations by a hybrid isentropic-sigma model, demonstrating the effect of coupling an isentropic-coordinate free atmospheric domain with a sigma-coordinate PBL on the normal-mode characteristics. Next, the normal-mode model was modified by including a transport equation for water vapor and adiabatic heating by condensation. Simulations with and without a hydrological component showed that the overall effect of latent heat release is to markedly enhance cyclogenesis and frontogenesis.

  3. Isentropic Compression of Argon

    SciTech Connect

    H. Oona; J.C. Solem; L.R. Veeser, C.A. Ekdahl; P.J. Rodriquez; S.M. Younger; W. Lewis; W.D. Turley

    1997-08-01

    We are studying the transition of argon from an insulator to a conductor by compressing the frozen gas isentropically to pressures at which neighboring atomic orbitals overlap sufficiently to allow some electron motion between atoms. Argon and the other rare gases have closed electron shells and therefore remain montomic, even when they solidify. Their simple structure makes it likely that any measured change in conductivity is due to changes in the atomic structure, not in molecular configuration. As the crystal is compressed the band gap closes, allowing increased conductivity. We have begun research to determine the conductivity at high pressures, and it is our intention to determine the compression at which the crystal becomes a metal.

  4. Isentropic Analysis of Convective Motions

    NASA Technical Reports Server (NTRS)

    Pauluis, Olivier M.; Mrowiec, Agnieszka A.

    2013-01-01

    This paper analyzes the convective mass transport by sorting air parcels in terms of their equivalent potential temperature to determine an isentropic streamfunction. By averaging the vertical mass flux at a constant value of the equivalent potential temperature, one can compute an isentropic mass transport that filters out reversible oscillatory motions such as gravity waves. This novel approach emphasizes the fact that the vertical energy and entropy transports by convection are due to the combination of ascending air parcels with high energy and entropy and subsiding air parcels with lower energy and entropy. Such conditional averaging can be extended to other dynamic and thermodynamic variables such as vertical velocity, temperature, or relative humidity to obtain a comprehensive description of convective motions. It is also shown how this approach can be used to determine the mean diabatic tendencies from the three-dimensional dynamic and thermodynamic fields. A two-stream approximation that partitions the isentropic circulation into a mean updraft and a mean downdraft is also introduced. This offers a straightforward way to identify the mean properties of rising and subsiding air parcels. The results from the two-stream approximation are compared with two other definitions of the cloud mass flux. It is argued that the isentropic analysis offers a robust definition of the convective mass transport that is not tainted by the need to arbitrarily distinguish between convection and its environment, and that separates the irreversible convective overturning fromoscillations associated with gravity waves.

  5. Climate Simulations with an Isentropic Finite Volume Dynamical Core

    SciTech Connect

    Chen, Chih-Chieh; Rasch, Philip J.

    2012-04-15

    This paper discusses the impact of changing the vertical coordinate from a hybrid pressure to a hybrid-isentropic coordinate within the finite volume dynamical core of the Community Atmosphere Model (CAM). Results from a 20-year climate simulation using the new model coordinate configuration are compared to control simulations produced by the Eulerian spectral and FV dynamical cores of CAM which both use a pressure-based ({sigma}-p) coordinate. The same physical parameterization package is employed in all three dynamical cores. The isentropic modeling framework significantly alters the simulated climatology and has several desirable features. The revised model produces a better representation of heat transport processes in the atmosphere leading to much improved atmospheric temperatures. We show that the isentropic model is very effective in reducing the long standing cold temperature bias in the upper troposphere and lower stratosphere, a deficiency shared among most climate models. The warmer upper troposphere and stratosphere seen in the isentropic model reduces the global coverage of high clouds which is in better agreement with observations. The isentropic model also shows improvements in the simulated wintertime mean sea-level pressure field in the northern hemisphere.

  6. Results from Isentropic Compression Experiments (ICE)

    SciTech Connect

    Tasker, D. G.; Goforth, J. H.; Oona, H.; Rigg, P. A.; Dennis-Koller, D.; King, J.; Torres, D.; Herrera, D.; Sena, F.; Abeyta, F.; Tabaka, L.

    2006-07-28

    We have developed high explosive pulsed power (HEPP) methods to obtain accurate isentropic EOS data with the isentropic compression experiment (ICE). In the HEPP-ICE experiment, fast rising current pulses (with risetimes from 400 to 600 ns) at current densities of many MA/cm, create continuous magnetic compression of materials to Mbar pressures. The response of materials to this isentropic loading, as determined with VISAR measurements of free surfaces, provides the required isentropic EOS. Experiments on copper will be presented here. The data are analyzed using conventional Lagrangian and Backward techniques. In the present arrangement four samples can be studied at one time, but accurate EOS data can only be obtained from opposing sample pairs, because it is only these pairs that share the same magnetic fields.

  7. Isentropic fluid dynamics in a curved pipe

    NASA Astrophysics Data System (ADS)

    Colombo, Rinaldo M.; Holden, Helge

    2016-10-01

    In this paper we study isentropic flow in a curved pipe. We focus on the consequences of the geometry of the pipe on the dynamics of the flow. More precisely, we present the solution of the general Cauchy problem for isentropic fluid flow in an arbitrarily curved, piecewise smooth pipe. We consider initial data in the subsonic regime, with small total variation about a stationary solution. The proof relies on the front-tracking method and is based on [1].

  8. Isentropic Analysis of a Simulated Hurricane

    NASA Technical Reports Server (NTRS)

    Mrowiec, Agnieszka A.; Pauluis, Olivier; Zhang, Fuqing

    2016-01-01

    Hurricanes, like many other atmospheric flows, are associated with turbulent motions over a wide range of scales. Here the authors adapt a new technique based on the isentropic analysis of convective motions to study the thermodynamic structure of the overturning circulation in hurricane simulations. This approach separates the vertical mass transport in terms of the equivalent potential temperature of air parcels. In doing so, one separates the rising air parcels at high entropy from the subsiding air at low entropy. This technique filters out oscillatory motions associated with gravity waves and separates convective overturning from the secondary circulation. This approach is applied here to study the flow of an idealized hurricane simulation with the Weather Research and Forecasting (WRF) Model. The isentropic circulation for a hurricane exhibits similar characteristics to that of moist convection, with a maximum mass transport near the surface associated with a shallow convection and entrainment. There are also important differences. For instance, ascent in the eyewall can be readily identified in the isentropic analysis as an upward mass flux of air with unusually high equivalent potential temperature. The isentropic circulation is further compared here to the Eulerian secondary circulation of the simulated hurricane to show that the mass transport in the isentropic circulation is much larger than the one in secondary circulation. This difference can be directly attributed to the mass transport by convection in the outer rainband and confirms that, even for a strongly organized flow like a hurricane, most of the atmospheric overturning is tied to the smaller scales.

  9. Isentropic Analysis of a Simulated Hurricane

    NASA Technical Reports Server (NTRS)

    Mrowiec, Agnieszka A.; Pauluis, Olivier; Zhang, Fuqing

    2016-01-01

    Hurricanes, like many other atmospheric flows, are associated with turbulent motions over a wide range of scales. Here the authors adapt a new technique based on the isentropic analysis of convective motions to study the thermodynamic structure of the overturning circulation in hurricane simulations. This approach separates the vertical mass transport in terms of the equivalent potential temperature of air parcels. In doing so, one separates the rising air parcels at high entropy from the subsiding air at low entropy. This technique filters out oscillatory motions associated with gravity waves and separates convective overturning from the secondary circulation. This approach is applied here to study the flow of an idealized hurricane simulation with the Weather Research and Forecasting (WRF) Model. The isentropic circulation for a hurricane exhibits similar characteristics to that of moist convection, with a maximum mass transport near the surface associated with a shallow convection and entrainment. There are also important differences. For instance, ascent in the eyewall can be readily identified in the isentropic analysis as an upward mass flux of air with unusually high equivalent potential temperature. The isentropic circulation is further compared here to the Eulerian secondary circulation of the simulated hurricane to show that the mass transport in the isentropic circulation is much larger than the one in secondary circulation. This difference can be directly attributed to the mass transport by convection in the outer rainband and confirms that, even for a strongly organized flow like a hurricane, most of the atmospheric overturning is tied to the smaller scales.

  10. Isentropic Compression Experiments on the Z Accelerator

    SciTech Connect

    Asay, J.R.

    1999-06-16

    This paper provides a brief review of experimental techniques for producing dynamic isentropic compression of samples to pressures of several hundred GPa. Traditional gun launch techniques include use of buffer plates, such as fused silica, that exhibit negative curvature to their stress-strain response and graded-density impactors. Graded-density impactors have been used to study isentropic compression of specimens to pressures exceeding 2 Mbar on high-impedance materials. A recent development includes the use of the Sandia Z Accelerator to produce magnetic compression in planar specimens to pressures of a few hundred kbar over time scales of 100 ns. These techniques have been successfully applied to isentropic compression of iron to 300 kbar and copper to 130 kbar. The iron results indicate that it is possible to study the polymorphic phase change that occurs at 130 kbar and also the kinetic properties of the transformation. The copper results indicate that with further improvements in progress it should be possible to measure continuous isentropic compression curves in materials of interest to pressures exceeding 1 Mbar. The Z accelerator is limited to peak currents of about 20 MA. By reconfiguring the anode-cathode geometry it should be possible to obtain constant current density and thus driving pressure to about 3 Mbar. The next generation accelerator referred to as ZX, which is being proposed will have the capability to generate currents to 50 MA and resulting peak pressures to 15 Mbar.

  11. Analytical Solution for Isentropic Flows in Solids

    NASA Astrophysics Data System (ADS)

    Heuzé, Olivier

    2009-12-01

    In the XIXth century, Riemann gave the equations system and the exact solution for the isentropic flows in the case of the ideal gas. But to our knowledge, nothing has been done to apply it to condensed media. Many materials of practical interest, for instance metals, obey to the linear law D = c+s u, where D is the shock velocity, u the particle velocity, and c and s properties of the material. We notice that s is strongly linked to the fundamental derivative. This means that the assumption of constant fundamental derivative is useful in this case, as it was with the isentropic gamma in the Riemann solution. Then we can apply the exact Riemann solution for these materials. Although the use of the hypergeometric function is complicated in this case, we obtain a very good approximation with the development in power series.

  12. Quasi-isentropic laser engines

    NASA Technical Reports Server (NTRS)

    Garbuny, M.

    1978-01-01

    This study examines laser engine processes in which coherent radiation is converted, at least in principle, completely into mechanical work (i.e., without the need for heat rejection). This type of engine process utilizes all coherence properties with minimum degradation, i.e., with minimum increase of entropy. The conversion is based on a heat pump operated by gaseous resonance absorption, followed by a heat engine.

  13. Air motion determination by tracking humidity patterns in isentropic layers

    NASA Technical Reports Server (NTRS)

    Mancuso, R. L.; Hall, D. J.

    1975-01-01

    Determining air motions by tracking humidity patterns in isentropic layers was investigated. Upper-air rawinsonde data from the NSSL network and from the AVE-II pilot experiment were used to simulate temperature and humidity profile data that will eventually be available from geosynchronous satellites. Polynomial surfaces that move with time were fitted to the mixing-ratio values of the different isentropic layers. The velocity components of the polynomial surfaces are part of the coefficients that are determined in order to give an optimum fitting of the data. In the mid-troposphere, the derived humidity motions were in good agreement with the winds measured by rawinsondes so long as there were few or no clouds and the lapse rate was relatively stable. In the lower troposphere, the humidity motions were unreliable primarily because of nonadiabatic processes and unstable lapse rates. In the upper troposphere, the humidity amounts were too low to be measured with sufficient accuracy to give reliable results. However, it appears that humidity motions could be used to provide mid-tropospheric wind data over large regions of the globe.

  14. Isentropic Compression Facility for the New Millennium

    NASA Astrophysics Data System (ADS)

    Willis, Michael

    2005-07-01

    Recent advances in the application of pulsed power to the study of dynamic material response have been made on the Sandia Z accelerator. Smoothly increasing multi-megabar pressure loads have been achieved allowing quasi-isentropes for these materials to be inferred. A significant amount of material research does not, however, require such intense pressure loading. In response to this, Sandia National Laboratories is constructing a facility that will house a compact Isentropic Compression Experiment (ICE) pulsed power driver capable of producing currents of ˜ 4 MA, and subsequent pressure loads on 4 samples up to ˜1 Mbar to provide a more cost effective, easily accessed machine for dynamic material studies. Additionally, a single stage air gun will be available to support the pulser as well as for standard, low velocity EOS experiments. Instrumentation will include conventional VISAR with ultra low VPF capability, spatially resolved VISAR, flash X-rays, and sample temperature control. An overview of the facility and unique capabilities will be shown. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DE-ACO4-94AL85000.

  15. An isentropic compression-heated Ludweig tube transient wind tunnel

    NASA Technical Reports Server (NTRS)

    Magari, Patrick J.; Lagraff, John E.

    1991-01-01

    Theoretical development and experimental results show that the Ludweig tube with isentropic heating (LICH) transient wind tunnel described is a viable means of producing flow conditions that are suitable for a variety of experimental investigations. A complete analysis of the wave dynamics of the pump tube compression process is presented. The LICH tube operating conditions are very steady and run times are greater than those of other types of transient facilities such as shock tubes and gas tunnels. This facility is well suited for producing flow conditions that are dynamically similar to those found in a gas turbine, i.e., transonic Mach number, gas-to-wall temperature ratios of about 1.5, and Reynolds numbers greater than 10 to the 6th.

  16. Generalized Forchheimer Flows of Isentropic Gases

    NASA Astrophysics Data System (ADS)

    Celik, Emine; Hoang, Luan; Kieu, Thinh

    2017-01-01

    We consider generalized Forchheimer flows of either isentropic gases or slightly compressible fluids in porous media. By using Muskat's and Ward's general form of the Forchheimer equations, we describe the fluid dynamics by a doubly nonlinear parabolic equation for the appropriately defined pseudo-pressure. The volumetric flux boundary condition is converted to a time-dependent Robin-type boundary condition for this pseudo-pressure. We study the corresponding initial boundary value problem, and estimate the L^∞ and W^{1,2-a} (with 0

  17. Isentropic Compression Studies of Energetic Composite Constituents

    NASA Astrophysics Data System (ADS)

    Baer, M. R.; Hobbs, M. L.; Hall, C. A.; Hooks, D. E.; Gustavsen, R. L.; Dattelbaum, D.; Sheffield, S. A.

    2007-12-01

    A series of quasi-isentropic magnetic pulse compression experiments using the Sandia Z accelerator and DICE small pulser have provided new insights to the material behavior of various constituents typically used in energetic composites. In this study, a combination of forward and backward procedures with optimization methods is used to determine appropriate constitutive and EOS property data. Sensitivity analysis is performed to assess the uncertainties of the experimental measurements and the subsequent influences in determining material response. The data interrogation technique has been applied to a series of tests with ramp loading condition to 50 Kbar over duration of ˜500 ns for panel configurations containing explosive crystals (HMX and RDX), binders (Estane, C7-Teflon, Kel-F and THV) and composites (PBS9501, PBX9502, and Al/Teflon).

  18. Shock compression and isentropic release of rhyolite

    NASA Astrophysics Data System (ADS)

    Yang, W.; Chen, G.; Anderson, W. W.; Ahrens, Thomas J.

    1994-07-01

    A series of shock compression experiments have been conducted on rhyolite at pressure ranging from 6 to 33 GPa. A velocity interferometer (VISAR) was employed to monitor the particle velocity of an aluminum reflector with a diffused surface bonded to the rhyolite sample. In the forward ballistic experiments, a slow rise shock wave front is observed at 6 GPa. While in the forward experiments their release waves are smeared, in a reverse ballistic experiment, the particle velocity variation at the shock wave plateau and the isentropic release wave arrival have been clearly observed. Using Swegle's mixed phase model, we simulated the experimental results with WONDY code. Like quartz and granite, the rhyolite data could be fit to a frozen release model which has some hysteric behavior. The Eulerian sound velocity at shock pressure 8.7 GPa has been determined to be 5.6 km/s.

  19. IWA : an analysis program for isentropic wave measurements.

    SciTech Connect

    Ao, Tommy

    2009-02-01

    IWA (Isentropic Wave Analysis) is a program for analyzing velocity profiles of isentropic compression experiments. IWA applies incremental impedance matching correction to measured velocity profiles to obtain in-situ particle velocity profiles for Lagrangian wave analysis. From the in-situ velocity profiles, material properties such as wave velocities, stress, strain, strain rate, and strength are calculated. The program can be run in any current version of MATLAB (2008a or later) or as a Windows XP executable.

  20. Planetary Torque in 3D Isentropic Disks

    NASA Astrophysics Data System (ADS)

    Fung, Jeffrey; Masset, Frédéric; Lega, Elena; Velasco, David

    2017-03-01

    Planetary migration is inherently a three-dimensional (3D) problem, because Earth-size planetary cores are deeply embedded in protoplanetary disks. Simulations of these 3D disks remain challenging due to the steep resolution requirements. Using two different hydrodynamics codes, FARGO3D and PEnGUIn, we simulate disk-planet interaction for a one to five Earth-mass planet embedded in an isentropic disk. We measure the torque on the planet and ensure that the measurements are converged both in resolution and between the two codes. We find that the torque is independent of the smoothing length of the planet’s potential (r s), and that it has a weak dependence on the adiabatic index of the gaseous disk (γ). The torque values correspond to an inward migration rate qualitatively similar to previous linear calculations. We perform additional simulations with explicit radiative transfer using FARGOCA, and again find agreement between 3D simulations and existing torque formulae. We also present the flow pattern around the planets that show active flow is present within the planet’s Hill sphere, and meridional vortices are shed downstream. The vertical flow speed near the planet is faster for a smaller r s or γ, up to supersonic speeds for the smallest r s and γ in our study.

  1. Measurement and analysis of release isentropes using proton radiography (u)

    SciTech Connect

    Schwartz, Cynthia L; Rigg, Paulo A; Cherne, Frank J; Hixson, Rob S; Greff, Carl W

    2011-01-25

    Off-Hugoniot measurements are needed to further develop predictive models that accurately describe the behavior of metals undergoing phase transitions. Predictive modeling of phase transitions is essential for LANL to meet its programmatic objectives. Understanding the dynamic evolution of density as a function of time during the release process is important to developing high fidelity equation of state models. This is particularly true for metals that have a degree of complexity, such as a solid-solid phase transition. The equations-of-state (EOS) for metals with complexity are more difficult to measure and to model, and states far away from where measurements are easily made can be poorly known. Accurate density measurements can provide us with additional fundamental information that can be used to further constrain the equation of state for a material. Currently release isentrope information is obtained from shock experiments at a sample window interface using optical velocimetry. This data is highly convoluted due to wave interactions between the sample window-interface making it difficult to infer physical processes happening within the material. Proton radiography has the ability to probe the release waves in-situ before these wave interactions can take place. Since multiple radiographs are obtained in each experiment, pRad provides the unique capability of being able to measure both density and wave evolution within the material. The measurement of release wave densities, however, presents new challenges for pRad since the release wave of a shocked transition is not a step function but instead a ramped wave. Previous pRad experiments have generally measured density jumps over step transitions; therefore, new analysis techniques will have to be developed to measure the ramped density change of a release isentrope. Once developed, these new analysis techniques can also be used for experiments that involve ramped compression. This kind of compression is being

  2. The Explicit Planetary Isentropic-Coordinate (EPIC) Atmospheric Model

    NASA Astrophysics Data System (ADS)

    Dowling, T. E.; Fischer, A. S.; Gierasch, P. J.; Harrington, J.; LeBeau, R. P.; Santori, C. M.

    1998-04-01

    We describe a new general circulation model (GCM) designed for planetary atmospheric studies called the EPIC model. This is a finite-difference model based on the isentropic-coordinate scheme of Hsu and Arakawa (1990.Mon. Wea. Rev.118, 1933-1959). We report on previously undocumented modifications, additions, and key practical issues that experience running the model has revealed to be important. The model integrates the hydrostatic primitive equations, which are valid for large-scale atmospheric dynamics and include gravity waves (buoyancy waves), planetary waves (Rossby waves), and horizontally propagating sound waves (Lamb waves), but not vertically propagating sound waves because of the hydrostatic approximation. The vertical coordinate is entropy in the form of potential temperature, which coincides with material surfaces for adiabatic motion. This means that there is no vertical velocity except where there is heating, which improves accuracy and helps the model maintain conservation properties over long integrations. An isentropic vertical coordinate is natural for the atmospheres of Jupiter, Saturn, Uranus, and Neptune, which are believed to have essentially adiabatic interiors that match up with the bottom of the model and is also excellent for middle-atmosphere studies on any planet. Radiative processes are parameterized by Newtonian cooling, and the latent heat of ortho-para hydrogen conversion is included when appropriate, with a suitably defined mean potential temperature. The model is written with general map factors that make it easy to configure in oblate spherical, cylindrical, or Cartesian coordinates. The code includes optional Message Passing Interface (MPI) library calls and hence runs on any Unix-based parallel computer or network cluster. An optional graphical user interface to commercial visualization software facilitates control of the model and analysis of output. Memory is allocated dynamically such that the user does not recompile to

  3. Isentropic Cross-Tropopause Ozone Transport in the Northern Hemisphere

    NASA Technical Reports Server (NTRS)

    Jing, P.; Cunnold, D. M.; Wang, H. J.; Yang, E.-S.

    2004-01-01

    This paper investigates isentropic ozone exchange between the extratropical lower stratosphere and the subtropical upper troposphere in the Northern Hemisphere. The quantification method is based on the potential vorticity (PV) mapping of Stratospheric Aerosol and Gas Experiment (SAGE)-II ozone measurements and contour advection calculations using the NASA Goddard Space Center Data Assimilation Office (DAO) analysis for the year 1990. The magnitude of the annual isentropic stratosphere-to-troposphere ozone flux is calculated to be approximately twice the flux that is directed from the troposphere into the stratosphere. The net effect is that approx.46 x 10(exp 9) kg/yr of ozone are transferred quasi horizontally from the extratropical lower stratosphere into the subtropical upper troposphere between the isentropic surfaces of 330 and 370 K. The estimated monthly ozone fluxes show that the isentropic cross-tropopause ozone transport is stronger in summer/fall than in winter/ spring, and this seasonality is more obvious at the upper three levels (i.e., 345, 355, and 365 K) than at 335 K. The distributions of the estimated monthly ozone fluxes indicate that the isentropic stratosphere-to-troposphere ozone exchange is associated with wave breaking and occurs preferentially over the eastern Atlantic Ocean and northwest Africa in winter and over the Atlantic and Pacific Oceans in summer.

  4. Isentropic Cross-Tropopause Ozone Transport in the Northern Hemisphere.

    NASA Astrophysics Data System (ADS)

    Jing, P.; Cunnold, D. M.; Wang, H. J.; Yang, E.-S.

    2004-05-01

    This paper investigates isentropic ozone exchange between the extratropical lower stratosphere and the subtropical upper troposphere in the Northern Hemisphere. The quantification method is based on the potential vorticity (PV) mapping of Stratospheric Aerosol and Gas Experiment (SAGE)-II ozone measurements and contour advection calculations using the NASA Goddard Space Center Data Assimilation Office (DAO) analysis for the year 1990. The magnitude of the annual isentropic stratosphere-to-troposphere ozone flux is calculated to be approximately twice the flux that is directed from the troposphere into the stratosphere. The net effect is that 46 × 109 kg yr-1 of ozone are transferred quasi horizontally from the extratropical lower stratosphere into the subtropical upper troposphere between the isentropic surfaces of 330 and 370 K. The estimated monthly ozone fluxes show that the isentropic cross-tropopause ozone transport is stronger in summer/fall than in winter/ spring, and this seasonality is more obvious at the upper three levels (i.e., 345, 355, and 365 K) than at 335 K. The distributions of the estimated monthly ozone fluxes indicate that the isentropic stratosphere-to-troposphere ozone exchange is associated with wave breaking and occurs preferentially over the eastern Atlantic Ocean and northwest Africa in winter and over the Atlantic and Pacific Oceans in summer.


  5. Isentropic Compression Experiment on Aluminum Using the Z-Accelerator

    SciTech Connect

    Williamson, D.R.; Peterson, R.R.; Blanchard, J.P

    2003-07-15

    The capability of using the Z-Machine at Sandia to perform isentropic compression experiments has been discussed by Hall previously. Pressures exceeding 1.5 Mbar have been launched into materials and the pressure wave can be shaped by varying the load current in Z. In this paper, theoretical results will be presented for an aluminum sample in which we obtain isentropic equations of state (EOS) information.Obtaining the isentropic EOS is necessary in many scientific and technological fields for computer simulations. We will follow the procedure outlined by Reisman to determine the EOS. From these steps, we will determine the theoretical EOS of aluminum using data obtained from BUCKY. We will discuss any variances we have in our results due to the use of two different sets of EOS opacity data.The results presented here were obtained using BUCKY, a 1-D MHD code developed at University of Wisconsin-Madison. BUCKY is a code that simulates high energy density plasmas and target yields for Inertial Confinement Fusion (ICF). BUCKY was originally designed to study target physics and target chamber designs for ICF reactors but can be used to study Isentropic Compression Experiments.We will describe the procedure used to determine the velocity wave profile measurements that leads to determining EOS. From the velocity wave profile we will be able to determine the isentropic compression equations of state of the aluminum sample modeled.

  6. Isentropic transport and the seasonal cycle amplitude of CO2

    NASA Astrophysics Data System (ADS)

    Barnes, Elizabeth A.; Parazoo, Nicholas; Orbe, Clara; Denning, A. Scott

    2016-07-01

    Carbon-concentration feedbacks and carbon-climate feedbacks constitute one of the largest sources of uncertainty in future climate. Since the beginning of the modern atmospheric CO2 record, seasonal variations in CO2 have been recognized as a signal of the metabolism of land ecosystems, and quantitative attribution of changes in the seasonal cycle amplitude (SCA) of CO2 to ecosystem processes is critical for understanding and projecting carbon-climate feedbacks far into the 21st Century. Here the impact of surface carbon fluxes on the SCA of CO2 throughout the Northern Hemisphere troposphere is investigated, paying particular attention to isentropic transport across latitudes. The analysis includes both a chemical transport model GOES-Chem and an idealized tracer in a gray-radiation aquaplanet. The results of the study can be summarized by two main conclusions: (1) the SCA of CO2 roughly follows surfaces of constant potential temperature, which can explain the observed increase in SCA with latitude along pressure surfaces and (2) increasing seasonal fluxes in lower latitudes have a larger impact on the SCA of CO2 throughout most of the troposphere compared to increasing seasonal fluxes in higher latitudes. These results provide strong evidence that recently observed changes in the SCA of CO2 at high northern latitudes (poleward of 60°N) are likely driven by changes in midlatitude surface fluxes, rather than changes in Arctic fluxes.

  7. An objective isobaric/isentropic technique for upper air analysis

    NASA Technical Reports Server (NTRS)

    Mancuso, R. L.; Endlich, R. M.; Ehernberger, L. J.

    1981-01-01

    An objective meteorological analysis technique is presented whereby both horizontal and vertical upper air analyses are performed. The process used to interpolate grid-point values from the upper-air station data is the same as for grid points on both an isobaric surface and a vertical cross-sectional plane. The nearby data surrounding each grid point are used in the interpolation by means of an anisotropic weighting scheme, which is described. The interpolation for a grid-point potential temperature is performed isobarically; whereas wind, mixing-ratio, and pressure height values are interpolated from data that lie on the isentropic surface that passes through the grid point. Two versions (A and B) of the technique are evaluated by qualitatively comparing computer analyses with subjective handdrawn analyses. The objective products of version A generally have fair correspondence with the subjective analyses and with the station data, and depicted the structure of the upper fronts, tropopauses, and jet streams fairly well. The version B objective products correspond more closely to the subjective analyses, and show the same strong gradients across the upper front with only minor smoothing.

  8. An objective isobaric/isentropic technique for upper air analysis

    NASA Technical Reports Server (NTRS)

    Mancuso, R. L.; Endlich, R. M.; Ehernberger, L. J.

    1981-01-01

    An objective meteorological analysis technique is presented whereby both horizontal and vertical upper air analyses are performed. The process used to interpolate grid-point values from the upper-air station data is the same as for grid points on both an isobaric surface and a vertical cross-sectional plane. The nearby data surrounding each grid point are used in the interpolation by means of an anisotropic weighting scheme, which is described. The interpolation for a grid-point potential temperature is performed isobarically; whereas wind, mixing-ratio, and pressure height values are interpolated from data that lie on the isentropic surface that passes through the grid point. Two versions (A and B) of the technique are evaluated by qualitatively comparing computer analyses with subjective handdrawn analyses. The objective products of version A generally have fair correspondence with the subjective analyses and with the station data, and depicted the structure of the upper fronts, tropopauses, and jet streams fairly well. The version B objective products correspond more closely to the subjective analyses, and show the same strong gradients across the upper front with only minor smoothing.

  9. Inverse Analysis of Isentropic Compression Experiments, V0.1

    SciTech Connect

    Davis, Jean-Paul

    2005-04-01

    The purpose of the program INVICE is to extract information about the mechanical compression isentrope of a material by analysis of experimental velocity profile data. The software is used to analyze raw data from high-pressure isentropic compression experiments performed at various drive facilities (primarily the Z Machine at Sandia National Laboratories) as part of DOE’s Stockpile Stewardship Program or other programs studying condensed matter at high pressures. The program uses a two-step Lax-Wendroff finitedifferencing scheme to integrate the one-dimensional (planar) equations of motion backward in the Lagrangian spatial coordinate, and a downhill simplex method with optional simulated annealing to perform minimization for extracting an isentrope.

  10. Isentropic Compression of Iron with the Z Accelerator

    SciTech Connect

    Asay, J.R.; Bernard, M.A.; Hall, C.A.; Hayes, D.B.; Holland, K.G.; McDaniel, D.H.; Rosenthal, S.E.; Spielman, R.B.; Stygar, W.A.

    1999-06-10

    Development of isentropic loading techniques is a long standing goal of the shock physics community. The authors have used the Sandia Z Accelerator to produce smoothly increasing pressure loading on planar iron specimens over time durations of 100 ns and for pressures to 300 Mbar. Free surface velocity measurements on the rear surface of the continuously loaded specimens were made on specimens 0.5-mm and 0.8-mm thick and clearly show the effects of wave evolution into the well known two-wave structure resulting from the {alpha}-{var_epsilon} phase transition beginning at 125 kbar. The resulting wave profiles are analyzed with a rate-dependent, phase transition model to extract information on phase transformation kinetics for isentropic compression of iron. Comparison of the experiments and calculations demonstrate the value of isentropic loading for studying phase transition kinetics.

  11. Strong relaxation limit of multi-dimensional isentropic Euler equations

    NASA Astrophysics Data System (ADS)

    Xu, Jiang

    2010-06-01

    This paper is devoted to study the strong relaxation limit of multi-dimensional isentropic Euler equations with relaxation. Motivated by the Maxwell iteration, we generalize the analysis of Yong (SIAM J Appl Math 64:1737-1748, 2004) and show that, as the relaxation time tends to zero, the density of a certain scaled isentropic Euler equations with relaxation strongly converges towards the smooth solution to the porous medium equation in the framework of Besov spaces with relatively lower regularity. The main analysis tool used is the Littlewood-Paley decomposition.

  12. How to Plan and Analyze an Isentropic Compression Experiment (ICE)

    SciTech Connect

    Hare, D E

    2004-08-06

    This report is a how-to manual for planning and analyzing an Isentropic Compression Experiment (ICE). Here the specific task is to find the unreacted Hugoniot of high explosive (HE) using Sandia National Laboratories Z-machine facility. However, many of the principles are broadly applicable to general ICE problems.

  13. Isentropic compression experiments on the Sandia Z accelerator

    SciTech Connect

    HALL,CLINT A.

    2000-02-21

    A long-standing goal of the equation of state (EOS) community has been the development of a loading capability for direct measurement of material properties along an isentrope. Previous efforts on smooth bore launchers have been somewhat successful, but quite difficult to accurately reproduce, had pressure limitations, or tended to be a series of small shocks as opposed to a smoothly increasing pressure load. A technique has recently been developed on the Sandia National Laboratories Z accelerator which makes use of the high current densities and magnetic fields available to produce nearly isentropic compression of samples that are approximately 1 mm in thickness over approximately 120 ns. Velocity interferometry is used to measure the rear surface motion of these samples. The resulting time resolved velocity profiles from multiple sample thicknesses provide information about mechanical response under isentropic loading conditions and phase transition kinetics. Feasibility experiments have been performed to pressures of approximately 130 kbar in copper and 300 kbar in iron with effects of the {alpha}-{var_epsilon} phase change kinetics in iron clearly observed. Work is in progress to achieve 1--2% accuracy in P-v space along an isentrope, provide uniaxial strain, and to eliminate magnetic field and current diffusion within the sample of interest.

  14. Seasonal Ozone Variations in the Isentropic Layer between 330 and 380 K as Observed by SAGE 2: Implications of Extratropical Cross-Tropopause Transport

    NASA Technical Reports Server (NTRS)

    Wang, Pi-Huan; Cunnold, Derek M.; Zawodny, Joseph M.; Pierce, R. Bradley; Olson, Jennifer R.; Kent, Geoffrey S.; Skeens, Kristi, M.

    1998-01-01

    To provide observational evidence on the extratropical cross-tropopause transport between the stratosphere and the troposphere via quasi-isentropic processes in the middleworld (the part of the atmosphere in which the isentropic surfaces intersect the tropopause), this report presents an analysis of the seasonal variations of the ozone latitudinal distribution in the isentropic layer between 330 K and 380 K based on the measurements from the Stratospheric Aerosol and Gas Experiment (SAGE) II. The results from SAGE II data analysis are consistent with (1) the buildup of ozone-rich air in the extratropical middleworld through the large-scale descending mass circulation during winter, (2) the spread of ozone-rich air in the isentropic layer from midlatitudes to subtropics via quasi-isentropic transport during spring, (3) significant photochemical ozone removal and the absence of an ozone-rich supply of air to the layer during summer, and (4) air mass exchange between the subtropics and the extratropics during the summer monsoon period. Thus the SAGE II observed ozone seasonal variations in the middleworld are consistent with the existing model calculated annual cycle of the diabatic circulation as well as the conceptual role of the eddy quasi-adiabatic transport in the stratosphere-troposphere exchange reported in the literature.

  15. The VELOCE pulsed power generator for isentropic compression experiments

    SciTech Connect

    Ao, Tommy; Asay, James Russell; Chantrenne, Sophie J.; Hickman, Randall John; Willis, Michael David; Shay, Andrew W.; Grine-Jones, Suzi A.; Hall, Clint Allen; Baer, Melvin R.

    2007-12-01

    Veloce is a medium-voltage, high-current, compact pulsed power generator developed for isentropic and shock compression experiments. Because of its increased availability and ease of operation, Veloce is well suited for studying isentropic compression experiments (ICE) in much greater detail than previously allowed with larger pulsed power machines such as the Z accelerator. Since the compact pulsed power technology used for dynamic material experiments has not been previously used, it is necessary to examine several key issues to ensure that accurate results are obtained. In the present experiments, issues such as panel and sample preparation, uniformity of loading, and edge effects were extensively examined. In addition, magnetohydrodynamic (MHD) simulations using the ALEGRA code were performed to interpret the experimental results and to design improved sample/panel configurations. Examples of recent ICE studies on aluminum are presented.

  16. Laser-direct-driven quasi-isentropic experiments on aluminum

    SciTech Connect

    Xue, Quanxi; Wang, Zhebin; Jiang, Shaoen Wang, Feng; Ye, Xisheng; Liu, Jingru

    2014-07-15

    Laser-direct-driven ramp compression experiments were performed on long temporally shaped laser pulses based on an analytical isentropic compression model. Upper pressure limits, the ablation pressure scaling law, and stress-density curves were studied. The validity of the analytical model used, the ablation pressure scaling law, and the phenomena of missing line-imaging velocity interferometer (VISAR) fringes in the experimental results are discussed.

  17. Isentropic Compression of Multicomponent Mixtures of Fuels and Inert Gases

    NASA Technical Reports Server (NTRS)

    Barragan, Michelle; Julien, Howard L.; Woods, Stephen S.; Wilson, D. Bruce; Saulsberry, Regor L.

    2000-01-01

    In selected aerospace applications of the fuels hydrazine and monomethythydrazine, there occur conditions which can result in the isentropic compression of a multicomponent mixture of fuel and inert gas. One such example is when a driver gas such as helium comes out of solution and mixes with the fuel vapor, which is being compressed. A second example is when product gas from an energetic device mixes with the fuel vapor which is being compressed. Thermodynamic analysis has shown that under isentropic compression, the fuels hydrazine and monomethylhydrazine must be treated as real fluids using appropriate equations of state. The appropriate equations of state are the Peng-Robinson equation of state for hydrazine and the Redlich-Kwong-Soave equation of state for monomethylhydrazine. The addition of an inert gas of variable quantity and input temperature and pressure to the fuel compounds the problem for safety design or analysis. This work provides the appropriate thermodynamic analysis of isentropic compression of the two examples cited. In addition to an entropy balance describing the change of state, an enthalpy balance is required. The presence of multicomponents in the system requires that appropriate mixing rules are identified and applied to the analysis. This analysis is not currently available.

  18. Isentropic Compression of Multicomponent Mixtures of Fuels and Inert Gases

    NASA Technical Reports Server (NTRS)

    Barragan, Michelle; Julien, Howard L.; Woods, Stephen S.; Wilson, D. Bruce; Saulsberry, Regor L.

    2000-01-01

    In selected aerospace applications of the fuels hydrazine and monomethythydrazine, there occur conditions which can result in the isentropic compression of a multicomponent mixture of fuel and inert gas. One such example is when a driver gas such as helium comes out of solution and mixes with the fuel vapor, which is being compressed. A second example is when product gas from an energetic device mixes with the fuel vapor which is being compressed. Thermodynamic analysis has shown that under isentropic compression, the fuels hydrazine and monomethylhydrazine must be treated as real fluids using appropriate equations of state. The appropriate equations of state are the Peng-Robinson equation of state for hydrazine and the Redlich-Kwong-Soave equation of state for monomethylhydrazine. The addition of an inert gas of variable quantity and input temperature and pressure to the fuel compounds the problem for safety design or analysis. This work provides the appropriate thermodynamic analysis of isentropic compression of the two examples cited. In addition to an entropy balance describing the change of state, an enthalpy balance is required. The presence of multicomponents in the system requires that appropriate mixing rules are identified and applied to the analysis. This analysis is not currently available.

  19. Verification of conventional equations of state for tantalum under quasi-isentropic compression

    SciTech Connect

    Binqiang, Luo; Guiji, Wang; Jianjun, Mo; Hongpin, Zhang; Fuli, Tan; Jianheng, Zhao; Cangli, Liu; Chengwei, Sun

    2014-11-21

    Shock Hugoniot data have been widely used to calibrate analytic equations of state (EOSs) of condensed matter at high pressures. However, the suitability of particular analytic EOSs under off-Hugoniot states has not been sufficiently verified using experimental data. We have conducted quasi-isentropic compression experiments (ICEs) of tantalum using the compact pulsed power generator CQ-4, and explored the relation of longitudinal stress versus volume of tantalum under quasi-isentropic compression using backward integration and characteristic inverse methods. By subtracting the deviatoric stress and additional pressure caused by irreversible plastic dissipation, the isentropic pressure can be extracted from the longitudinal stress. Several theoretical isentropes are deduced from analytic EOSs and compared with ICE results to validate the suitability of these analytic EOSs in isentropic compression states. The comparisons show that the Gruneisen EOS with Gruneisen Gamma proportional to volume is accurate, regardless whether the Hugoniot or isentrope is used as the reference line. The Vinet EOS yields better accuracy in isentropic compression states. Theoretical isentropes derived from Tillotson, PUFF, and Birch-Murnaghan EOSs well agree with the experimental isentrope in the range of 0–100 GPa, but deviate gradually with pressure increasing further.

  20. Isentropic compressive wave generator and method of making same

    DOEpatents

    Barker, L.M.

    An isentropic compressive wave generator and method of making same are disclosed. The wave generator comprises a disk or flat pillow member having component materials of different shock impedances formed in a configuration resulting in a smooth shock impedance gradient over the thickness thereof for interpositioning between an impactor member and a target specimen for producing a shock wave of a smooth predictable rise time. The method of making the pillow member comprises the reduction of the component materials to a powder form and forming the pillow member by sedimentation and compressive techniques.

  1. A Study of Polymer Materials Subjected to Isentropic Compression Loading

    NASA Astrophysics Data System (ADS)

    Hall, C. A.; Baer, M. R.; Gustavsen, R. L.; Hooks, D. E.; Orler, E. Bruce; Dattelbaum, D. M.; Sheffield, S. A.; Sutherland, G. T.

    2006-07-01

    This work applies a ramped, quasi-isentropic compression loading technique (ICE) to investigate the mechanical behavior of polymers that are often used in energetic composites. The focus of this effort is the determination of appropriate constitutive and EOS property data at high stress states and moderate strain rates that is needed for detailed mesoscale modeling. Several thicknesses of samples were subjected to a ramp load of ˜45 Kbar over 500 ns duration using the Sandia Z-machine. Profiles of transmitted ramp waves were measured at window interfaces using conventional VISAR. Shock physics analysis is then used to determine the nonlinear material response of the binder materials.

  2. A study of binder materials subjected to isentropic compression loading.

    SciTech Connect

    Hall, Clint Allen; Orler, E. Bruce; Sheffield, Steve A; Gustavsen, Rick L.; Sutherland, Gerrit; Baer, Melvin R.; Hooks, D.E.

    2005-07-01

    Binders such as Estane, Teflon, Kel F and HTPB are typically used in heterogeneous explosives to bond polycrystalline constituents together as an energetic composite. Combined theoretical and experimental studies are underway to unravel the mechanical response of these materials when subjected to isentropic compression loading. Key to this effort is the determination of appropriate constitutive and EOS property data at extremely high stress-strain states as required for detailed mesoscale modeling. The Sandia Z accelerator and associated diagnostics provides new insights into mechanical response of these nonreactive constituents via isentropic ramp-wave compression loading. Several thicknesses of samples, varied from 0.3 to 1.2 mm, were subjected to a ramp load of {approx}42 Kbar over 500 ns duration using the Sandia Z-machine. Profiles of transmitted ramp waves were measured at window interfaces using conventional VISAR. Shock physics analysis is then used to determine the nonlinear material response of the binder materials. In this presentation we discuss experimental and modeling details of the ramp wave loading ICE experiments designed specifically for binder materials.

  3. Simultaneous determination of Hugoniot and Isentrope in gas gun experiments

    SciTech Connect

    Thoe, R S

    2007-02-22

    We have been exploring the use of the ''reverse ballistics'' method to obtain Hugoniot and off Hugoniot Equation Of State. This method uses the unknown sample as the flyer and collides it into a window whose EOS is well known. A VISAR determines the particle velocity which when combined with the windows EOS gives a direct determination of the pressure. Since the pressure and particle velocity are continuous across the interface the shock speed in the flyer can be determined: Us = P/(rhoUp). Subtracting the time of arrival of the shock at the back of the flyer from the times of arrival of the rarefaction wave allows the determination of the release isentrope centered at the measured Hugoniot point and extending down to the release pressure as determined by the impedance of the sabot. Besides obtaining both Hugoniot and isentrope data on a single shot, this method has an advantage in that all the timing information is accomplished within the interferometer, i.e. no dependence of cable delays etc.

  4. A Compact Pulser for Magnetically Driven Isentropic-Compression Experiments

    NASA Astrophysics Data System (ADS)

    Spielman, R. B.; Bavay, M.; Mervini, J. A.; Avrillaud, G.

    2007-06-01

    The use of magnetic fields to isentropically compress materials for equation-of-state studies has been demonstrated on Sandia National Laboratories' Z machine. Sharing similarities with the GEPI pulser at the Centre de Etudes de Gramat in France, a compact pulser has been designed and built specifically for isentropic compression experiments. In order to be compact and low cost, the design uses a solid dielectric transmission line to couple current from eight low-inductance Haefely capacitors that are switched with ultra-low-inductance multi-channel gas switches. A peaking stage made of 72 General Atomics capacitors enhanced by a low-inductance, multi-channel peaking switch brings the fundamental rise time of the pulser down to 350 ns (10-90%). A varaible inductance in parallel with the peaking switch as well as using various gases in the switch allow us to control the details of the current wave shape. The pulser delivers a peak current of 4 MA at a charge voltage of 80 kV into a short circuit. The rise time can be lengthened to greater than 650 ns to deliver a current of 4.2 MA. The performance of this pulser will be described along with potential design changes that would provide decreases in current rise time and increases in current delivered to real world loads.

  5. Z-Pinch Driven Isentropic Compression for Inertial Fusion

    SciTech Connect

    Asay, J.R.; Hall, C.A.; Holland, K.G.; Slutz, S.A.; Spielman, R.B.; Stygar, W.A.

    1999-02-01

    The achievement of high gain with inertial fusion requires the compression of hydrogen isotopes to high density and temperatures. High densities can be achieved most efficiently by isentropic compression. This requires relatively slow pressure pulses on the order of 10-20 nanoseconds; however, the pressure profile must have the appropriate time. We present 1-D numerical simulations that indicate such a pressure profile can be generated by using pulsed power driven z pinches. Although high compression is calculated, the initial temperature is too low for ignition. Ignition could be achieved by heating a small portion of this compressed fuel with a short (-10 ps) high power laser pulse as previously described. Our 1-D calculations indicate that the existing Z-accelerator could provide the driving current (-20 MA) necessary to compress fuel to roughly 1500 times solid density. At this density the required laser energy is approximately 10 kJ. Multidimensional effects such as the Rayleigh-Taylor were not addressed in this brief numerical study. These effects will undoubtedly lower fuel compression for a given chive current. Therefore it is necessary to perform z-pinch driven compression experiments. Finally, we present preliminary experimental data from the Z-accelerator indicating that current can be efficiently delivered to appropriately small loads (- 5 mm radius) and that VISAR can be used measure high pressure during isentropic compression.

  6. Design of a miniature explosive isentropic compression experiment

    SciTech Connect

    Tasker, Douglas G

    2010-01-01

    The purpose of this design study is to adapt the High Explosive Pulsed Power Isentropic Compression Experiment (HEPP-ICE) to milligram quantities of materials at stresses of {approx}100 GPa. For this miniature application we assume that a parallel plate stripline of {approx}2.5 mm width is needed to compress the samples. In any parallel plate load, the rising currents flow preferentially along the outside edges of the load where the specific impedance is a minimum [1]. Therefore, the peak current must be between 1 and 2 MA to reach a stress of 100 GPa in the center of a 2.5 mm wide parallel plate load; these are small relative to typical HEPP-ICE currents. We show that a capacitor bank alone exceeds the requirements of this miniature ICE experiment and a flux compression generator (FCG) is not necessary. The proposed circuit will comprise one half of the 2.4-MJ bank, i.e., the 6-mF, 20-kV, 1.2 MJ capacitor bank used in the original HEPP-ICE circuit. Explosive opening and closing switches will still be required because the rise time of the capacitor circuit would be of the order of 30 {micro}s without them. For isentropic loading in these small samples, stress rise times of {approx}200 ns are required.

  7. A model of stratospheric chemistry and transport on an isentropic surface

    NASA Technical Reports Server (NTRS)

    Austin, John; Holton, James R.

    1990-01-01

    This paper presents a new photochemical transport model designed to simulate the behavior of stratospheric trace species in the middle stratosphere. The model has an Eulerian grid with the latitude and longitude coordinates on a single isentropic surface (hemispheric or global), in which both the dynamical and the photochemical processes can be accurately represented. The model is intgegrated for 12 days with winds and temperatures supplied by three-dimensional integration of an idealized wavenumber-one disturbance. The results for the long-lived tracers such as N2O showed excellent correlation with the potential vorticity distribution, validating the transport scheme. Calculations with zonally averaged wind and temperature fields showed that discrepancies in the calculation of the zonal mean were less than 10 percent for O3 and HNO3, compared with the zonal mean of the previous results.

  8. Accessing ultrahigh-pressure, quasi-isentropic states of matter

    SciTech Connect

    Lorenz, K.T.; Edwards, M.J.; Glendinning, S.G.; Jankowski, A.F.; McNaney, J.; Pollaine, S.M.; Remington, B.A.

    2005-05-15

    A new approach to the study of material strength of metals at extreme pressures has been developed on the Omega laser, using a ramped plasma piston drive. The laser drives a shock through a solid plastic reservoir that unloads at the rear free surface, expands across a vacuum gap, and stagnates on the metal sample under study. This produces a gently increasing ram pressure, compressing the sample nearly isentropically. The peak pressure on the sample, inferred from interferometric measurements of velocity, can be varied by adjusting the laser energy and pulse length, gap size, and reservoir density, and obeys a simple scaling relation [J. Edwards et al., Phys. Rev. Lett. 92, 075002 (2004)]. In an important application, using in-flight x-ray radiography, the material strength of solid-state samples at high pressure can be inferred by measuring the reductions in the growth rates (stabilization) of Rayleigh-Taylor unstable interfaces. This paper reports the first attempt to use this new laser-driven, quasi-isentropic technique for determining material strength in high-pressure solids. Modulated foils of Al-6061-T6 were accelerated and compressed to peak pressures of {approx}200 kbar. Modulation growth was recorded at a series of times after peak acceleration and well into the release phase. Fits to the growth data, using a Steinberg-Guinan constitutive strength model, give yield strengths 38% greater than those given by the nominal parameters for Al-6061-T6. Calculations indicate that the dynamic enhancement to the yield strength at {approx}200 kbar is a factor of {approx}3.6x over the ambient yield strength of 2.9 kbar. Experimental designs based on this drive developed for the National Ignition Facility laser [W. Hogan, E. Moses, B. Warner, M. Sorem, and J. Soures, Nuclear Fusion 41, 567 (2001)] predict that solid-state samples can be quasi-isentropically driven to pressures an order of magnitude higher than on Omega, accessing new regimes of dense, high

  9. Accessing ultrahigh-pressure, quasi-isentropic states of mattera)

    NASA Astrophysics Data System (ADS)

    Lorenz, K. T.; Edwards, M. J.; Glendinning, S. G.; Jankowski, A. F.; McNaney, J.; Pollaine, S. M.; Remington, B. A.

    2005-05-01

    A new approach to the study of material strength of metals at extreme pressures has been developed on the Omega laser, using a ramped plasma piston drive. The laser drives a shock through a solid plastic reservoir that unloads at the rear free surface, expands across a vacuum gap, and stagnates on the metal sample under study. This produces a gently increasing ram pressure, compressing the sample nearly isentropically. The peak pressure on the sample, inferred from interferometric measurements of velocity, can be varied by adjusting the laser energy and pulse length, gap size, and reservoir density, and obeys a simple scaling relation [J. Edwards et al., Phys. Rev. Lett. 92, 075002 (2004)]. In an important application, using in-flight x-ray radiography, the material strength of solid-state samples at high pressure can be inferred by measuring the reductions in the growth rates (stabilization) of Rayleigh-Taylor unstable interfaces. This paper reports the first attempt to use this new laser-driven, quasi-isentropic technique for determining material strength in high-pressure solids. Modulated foils of Al-6061-T6 were accelerated and compressed to peak pressures of ˜200kbar. Modulation growth was recorded at a series of times after peak acceleration and well into the release phase. Fits to the growth data, using a Steinberg-Guinan constitutive strength model, give yield strengths 38% greater than those given by the nominal parameters for Al-6061-T6. Calculations indicate that the dynamic enhancement to the yield strength at ˜200kbar is a factor of ˜3.6× over the ambient yield strength of 2.9kbar. Experimental designs based on this drive developed for the National Ignition Facility laser [W. Hogan, E. Moses, B. Warner, M. Sorem, and J. Soures, Nuclear Fusion 41, 567 (2001)] predict that solid-state samples can be quasi-isentropically driven to pressures an order of magnitude higher than on Omega, accessing new regimes of dense, high-pressure matter.

  10. Metal liner-driven quasi-isentropic compression of deuterium

    SciTech Connect

    Weinwurm, Marcus; Bland, Simon N.; Chittenden, Jeremy P.

    2013-09-15

    Properties of degenerate hydrogen and deuterium (D) at pressures of the order of terapascals are of key interest to Planetary Science and Inertial Confinement Fusion. In order to recreate these conditions in the laboratory, we present a scheme, where a metal liner drives a cylindrically convergent quasi-isentropic compression in a D fill. We first determined an external pressure history for driving a self-similar implosion of a D shell from a fictitious flow simulation [D. S. Clark and M. Tabak, Nucl. Fusion 47, 1147 (2007)]. Then, it is shown that this D implosion can be recreated inside a beryllium liner by shaping the current pulse. For a peak current of 10.8 MA cold and nearly isochoric D is assembled at around 12 500 kg/m{sup 3}. Finally, our two-dimensional Gorgon simulations show the robustness of the implosion method to the magneto-Rayleigh-Taylor instability when using a sufficiently thick liner.

  11. Power calculations for isentropic compressions of cryogenic nitrogen

    NASA Technical Reports Server (NTRS)

    Adcock, J. B.; Ogburn, M. E.

    1977-01-01

    A theoretical analysis was made of the power required for isentropic compressions of cryogenic nitrogen in order to determine the extent to which the drive power for cryogenic tunnels might be affected by real-gas effects. The analysis covers temperatures from 80 to 310 K, pressures from 1.0 to 8.8 atm, and fan pressure ratios from 1.025 to 1.200. The power required to compress cryogenic nitrogen was found to be as much as 9.5 percent lower than that required to compress an ideal diatomic gas. Simple corrections to the ideal-gas values were found to give accurate estimates of the real-gas power values.

  12. Isentropic compression studies using the NHMFL single turn

    SciTech Connect

    Tasker, Douglas G; Mielke, Charles; Rodriguez, George; Rickel, Dwight

    2010-10-19

    Magnetic isentropic compression experiments (ICE) provide the most accurate shock free compression data for materials at megabar stresses. Recent ICE experiments performed on the Sandia Z-machine (Asay, 1999) and at the Los Alamos High Explosive Pulsed Power facility (Tasker, 2006) are providing our nation with data on material properties in extreme dynamic high stress environments. The LANL National High Magnetic Field Laboratory (NHMFL) can offer a less complex ICE experiment at high stresses (up to {approx}1Mbar) with a high sample throughput and relatively low cost. This is not to say that the NHMFL technique will replace the other methods but rather complement them. For example, NHMFL-ICE is ideal for the development of advanced diagnostics, e.g., to detect phase changes. We will discuss the physics of the NHMFL-ICE experiments and present data from the first proof-of-principle experiments that were performed in September 2010.

  13. Isentropic Compression Experiments for Mesoscale Studies of Energetic Composites

    NASA Astrophysics Data System (ADS)

    Baer, M. R.; Hall, C. A.; Gustavsen, R. L.; Hooks, D. E.; Sheffield, S. A.

    2006-07-01

    New experimental diagnostics and computational modeling provide an unprecedented means for improving the understanding of energetic material behavior at the mesoscale (grain or crystal ensemble levels). This study focuses on the determination of appropriate constitutive and EOS property data of the constituents of an energetic composite at high stress and moderate strain-rate states. The Sandia Z accelerator is used to determine the mechanical response of energetic composites via isentropic ramp wave compression loading. In this paper we describe an energy source method in CTH that models ramp loading for the analysis of ICE experiments. This approach is applied to design experimental configurations to probe the constituent response of PBX 9501 subjected to ˜40 Kbar ramp load over 300 ns duration. Multiple VISAR are used to determine the averaged response of the composite material in comparison to the individual constituents including the effects of anisotropy of HMX crystals and the interactions of fine crystallites with binder material.

  14. Isentropic analysis of polar cold air mass streams

    NASA Astrophysics Data System (ADS)

    Iwasaki, Toshiki; Kanno, Yuki

    2015-04-01

    1. Introduction A diagnostic method is presented of polar cold air mass streams defined below a threshold potential temperature. The isentropic threshold facilitates a Lagrangian view of the cold air mass streams from diabatic generation to disappearance. 2. Mass-weighted isentropic zonal mean (MIM) cold air streams In winter hemispheres, MIM's mass stream functions show a distinct extratropical direct (ETD) cell in addition to the Hadley cell. The mass stream functions have local maxima at around (280K, 45N) for NH winter and, around (280K, 50S) for SH winter. Thus, =280K may be appropriate to a threshold of the polar cold air mass for both hemispheres. The high-latitude downward motion indicates the diabatic generation of cold air mass, whereas the mid-latitude equatorward flow does its outbreak. The strength of equatorward flow is under significant control of wave-mean flow interactions. 3. Geographical distribution of the cold air mass streams in the NH winter In the NH winter, the polar cold air mass flux has two distinct mainstreams, hereafter called as East Asian (EA) stream and the North American (NA) stream. The former grows over the northern part of the Eurasian continent, turns down southeastward toward East Asia and disappears over the western North Pacific Ocean. The latter grows over the Arctic Ocean, flows toward the East Coast of North America and disappears over the western North Atlantic Ocean. These coincide well with main routes of cold surges. 4. Comparison between NH and SH winter streams The cold air mass streams in NH winter are more asymmetric than those in SH winter. The NH total cold air mass below =280K is about 1.5 times greater than the SH one. These come mainly from the topography and land-sea distribution. The mid-latitude mountains steer the cold air mass streams on the northern sides and enhance the residence time over its genesis region.

  15. Magnetically-Driven Isentropic Compression Status and Future Advances

    NASA Astrophysics Data System (ADS)

    Deeney, Christopher

    2005-07-01

    Since the development of magnetically driven isentropic compression experiments (ICE) on the Z accelerator by Asay et al, this technique has continued to grow in maturity. At lower pressures, isentropic compression has been employed to identify and then study phase transitions and their kinetics. In addition, experiments have used the same techniques to study re-solidification, the response of explosives, and the crush up of porous materials. Most of these experiments rely on the ability of ICE to generate very smooth ramps that can be applied to multiple samples for relative experiments. For equation of state studies, the intrinsic accuracy and peak pressures continue to demand improvement in understanding, analysis techniques and diagnostics. We have spent significant effort in these areas over the last few years because we believe that we must demonstrate a well characterized and understood method to obtain accurate EOS data with well-behaved materials to give confidence in future comparisons between ICE data and calculations of material properties. In our presentation, we will discuss the status of Z experiments, our recent data at multi-megabar pressures with aluminum and other materials, and the status of our analysis abilities. We will also discuss the need for future improvements in diagnostics plus the anticipated capabilities of the ZR facility and the small pulser. This work was supported by the United States Department of Energy's National Nuclear Security Administration under contract No. DE-AC04-94AL85000. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company..

  16. A conservative method for hydrostatic flow in isentropic coordinates

    NASA Astrophysics Data System (ADS)

    Peeters, B.; Bokhove, O.; Frank, J.

    2010-05-01

    Although our climate is ultimately driven by (nonuniform) solar heating, many aspects of the flow can be understood qualitatively from forcing-free and frictionless dynamics. In the limit of zero forcing and dissipation, our weather system falls under the realm of Hamiltonian fluid dynamics and the flow conserves potential vorticity (PV), energy and phase-space structure. We have found a conservative numerical scheme for a hydrostatic atmosphere based on a mixed Eulerian-Lagrangian approach, the so-called parcel formulation [1]. For adiabatic flow, the entropy is materially conserved. Under stable stratifications, we introduce isentropic coordinates to simplify the governing equations. The entropic direction is discretized using finite elements. The discretization of horizontal Lagrangian label space (from infinitesimal fluid parcels to discrete fluid particles) yields a discrete Poisson bracket. New is that we apply the Hamiltonian Particle-Mesh method [2], and view the potential as an Eulerian function, reconstructed from the particle data. The use of an Eulerian grid makes the method more efficient and stable. The Hamiltonian consists of a Lagrangian kinetic energy and an Eulerian potential energy. The discrete system of ODE's is thus a Hamiltonian system conserving mass, PV, energy and phase-space structure. If we incorporate a symplectic time integrator, the resulting fully discrete system conserves energy approximately without any drift in energy. Several challenging (nonlinear) solutions will be tested, such a flow over a rising bump. Also, preliminary results for bottom-intersecting isentropes will be demonstrated. REFERENCES [1] O. Bokhove and M. Oliver, Parcel Eulerian-Lagrangian fluid dynamics for rotating geophysical flows, Proc. Roy. Soc. A. 462, pp. 2563-2573 (2006) [2] J. Frank, G. Gottwald, S. Reich, A Hamiltonian particle-mesh method for the rotating shallow-water equations, Lecture Notes in Computational Science and Engineering, Vol. 26, Springer

  17. Isentropic thermal instability in atomic surface layers of photodissociation regions

    NASA Astrophysics Data System (ADS)

    Krasnobaev, K. V.; Tagirova, R. R.

    2017-08-01

    We consider the evolution of an isentropic thermal instability in the atomic zone of a photodissociation region (PDR). In this zone, gas heating and cooling are associated mainly with photoelectric emission from dust grains and fine-structure lines ([C II] 158, [O i] 63 and [O i] 146 μm), respectively. The instability criterion has a multi-parametric dependence on the conditions of the interstellar medium. We found that instability occurs when the intensity of the incident far-ultraviolet field G0 and gas density n are high. For example, we have 3 × 103 < G0 < 106 and 4.5 × 104 < n < 106 cm-3 at temperatures 360 < T < 104 K for optical thin fine-structure lines and for typical carbon and oxygen abundances ξC = 1.4 × 10-4 and ξO = 3.2 × 10-4. If we take line opacities into account, these ranges of G0, n and T are expanded. Moreover, the instability criterion depends significantly on the relation between ξC and ξO abundances. We also give examples of observed PDRs where instability could occur. For these PDRs, the characteristic perturbation growth time is tinst ∼ 103-104 yr and the distance characterizing the formation of secondary waves is L ∼ 10-3-5 × 10-2 pc. For objects that are older than tinst and have sizes of the atomic zone larger than L, we expect that instability influences the PDR structure significantly. The presence of multiple shock waves, turbulent velocities of several kilometres per second and inhomogeneities with higher density and temperature than the surrounding medium can characterize isentropic thermal instability in PDRs.

  18. An isentropic and sigma coordinate hybrid numerical model - Model development and some initial tests. [for atmospheric simulations

    NASA Technical Reports Server (NTRS)

    Uccellini, L. W.; Johnson, D. R.; Schlesinger, R. E.

    1979-01-01

    A solution is presented for matching boundary conditions across the interface of an isentropic and sigma coordinate hybrid model. A hybrid model based on the flux form of the primitive equations is developed which allows direct vertical exchange between the model domains, satisfies conservation principles with respect to transport processes, and maintains a smooth transition across the interface without need for artificial adjustment or parameterization schemes. The initial hybrid model simulations of a jet streak propagating in a zonal channel are used to test the feasibility of the hybrid model approach. High efficiency of the hybrid model is demonstrated.

  19. Compressible gas properties of UF/sub 6/ for isentropic, normal shock, and oblique shock conditions

    SciTech Connect

    Harloff, G.J.

    1984-11-01

    Isentropic, normal shock, and oblique shock tables are given for the real gas UF/sub 6/ for Mach numbers up to 22. An evaluation of the real gas effects is given. A computer program listing is included.

  20. Accessing Ultrahigh-Pressure, Quasi-Isentropic States of Matter

    NASA Astrophysics Data System (ADS)

    Lorenz, Thomas

    2004-11-01

    A new approach to materials science at extreme pressures has been developed on the OMEGA laser, using a ramped plasma piston drive. The laser drives a shock through a solid plastic reservoir that unloads at the rear free surface, expands across a vacuum gap, and stagnates on the metal sample under study. This produces a gently increasing ram pressure, compressing the sample nearly isentropically. The peak pressure on the sample, diagnosed with VISAR measurements, can be varied by adjusting the laser energy and pulse length, gap size, and reservoir density, and obeys a simple scaling relation. [1] This has been demonstrated at OMEGA at pressures of P = 0.1-2.0 Mbar in Al foils. [2] In an important application, using in-flight x-ray radiography, the material strength of solid-state samples at high pressure can be inferred by measuring the reductions in the growth rates (stabilization) of Rayleigh-Taylor (RT) unstable interfaces. The material strength is predicted to be as much as an order of magnitude higher at P ˜ 1 Mbar than at ambient pressures. Initial RT measurements testing this prediction in foils of Al and V will be shown. We also use TEM microscopy of recovered targets to show that the samples never melted, and the presence of pressure-induced structural defects. [3,4] Experimental designs based on this drive have been developed for the NIF laser, predicting that solid-state samples can be quasi-isentropically driven to pressures an order of magnitude higher than on Omega - accessing new regimes of dense, high-pressure matter. [5] [1] J. Edwards et al., Phys. Rev. Lett., 92, 075002 (2004). [2] K.T. Lorenz et al., submitted, J. Appl. Phys. (2004). [3] J. McNaney et al., in press, Met. Mat. Trans. 35A (2004). [4] E.M. Bringa et al., to be submitted, Nature (2004). [5] B.A. Remington et al., in press, Met. Mat. Trans. 35A (2004). This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore

  1. Isentropic Compression in a Strip Line, Numerical Simulations and Comparison with GEPI Shot 268

    SciTech Connect

    Lefrancois, A.; L'Eplattenier, P.; Burger, M.

    2006-02-13

    Isentropic compressions in a strip line geometry are performed on the GEPI facility at Centre d'etudes de Gramat in order to study isentrope, associated Hugoniot and phase changes. 3D GEPI configuration has been calculated here to test the new beta version of the electromagnetism package coupled with the dynamics in LS-DYNA{reg_sign} and compared with the GEPI experiment number 268.

  2. Isentropic Compression for TATB Based HE Samples, Numerical Simulations and Comparison with Experiments

    SciTech Connect

    Lefrancois, A; Vandersall, K; L'Eplattenier, P; Burger, M

    2006-02-06

    Isentropic compression experiments and numerical simulations on TATB based HE were performed respectively at Z accelerator facility from Sandia National Laboratory and at Lawrence Livermore National Laboratory in order to study the isentrope and associated Hugoniot of this HE [1]. 3D configurations have been calculated here to test the new beta version of the electromagnetism package coupled with the dynamics in Ls-Dyna and compared with the ICE Z shot 1967.

  3. Non-local thermodynamic equilibrium effects on isentropic coefficient in argon and helium thermal plasmas

    SciTech Connect

    Sharma, Rohit; Singh, Kuldip

    2014-03-15

    In the present work, two cases of thermal plasma have been considered; the ground state plasma in which all the atoms and ions are assumed to be in the ground state and the excited state plasma in which atoms and ions are distributed over various possible excited states. The variation of Zγ, frozen isentropic coefficient and the isentropic coefficient with degree of ionization and non-equilibrium parameter θ(= T{sub e}/T{sub h}) has been investigated for the ground and excited state helium and argon plasmas at pressures 1 atm, 10 atm, and 100 atm in the temperature range from 6000 K to 60 000 K. For a given value of non-equilibrium parameter, the relationship of Zγ with degree of ionization does not show any dependence on electronically excited states in helium plasma whereas in case of argon plasma this dependence is not appreciable till degree of ionization approaches 2. The minima of frozen isentropic coefficient shifts toward lower temperature with increase of non-equilibrium parameter for both the helium and argon plasmas. The lowering of non-equilibrium parameter decreases the frozen isentropic coefficient more emphatically in helium plasma at high pressures in comparison to argon plasma. The increase of pressure slightly reduces the ionization range over which isentropic coefficient almost remains constant and it does not affect appreciably the dependence of isentropic coefficient on non-equilibrium parameter.

  4. Separation of acoustic waves in isentropic flow perturbations

    SciTech Connect

    Henke, Christian

    2015-04-15

    The present contribution investigates the mechanisms of sound generation and propagation in the case of highly-unsteady flows. Based on the linearisation of the isentropic Navier–Stokes equation around a new pathline-averaged base flow, it is demonstrated for the first time that flow perturbations of a non-uniform flow can be split into acoustic and vorticity modes, with the acoustic modes being independent of the vorticity modes. Therefore, we can propose this acoustic perturbation as a general definition of sound. As a consequence of the splitting result, we conclude that the present acoustic perturbation is propagated by the convective wave equation and fulfils Lighthill’s acoustic analogy. Moreover, we can define the deviations of the Navier–Stokes equation from the convective wave equation as “true” sound sources. In contrast to other authors, no assumptions on a slowly varying or irrotational flow are necessary. Using a symmetry argument for the conservation laws, an energy conservation result and a generalisation of the sound intensity are provided. - Highlights: • First splitting of non-uniform flows in acoustic and non-acoustic components. • These result leads to a generalisation of sound which is compatible with Lighthill’s acoustic analogy. • A closed equation for the generation and propagation of sound is given.

  5. Modelling the effect of shear strength on isentropic compression experiments

    NASA Astrophysics Data System (ADS)

    Thomson, Stuart; Howell, Peter; Ockendon, John; Ockendon, Hilary

    2017-01-01

    Isentropic compression experiments (ICE) are a way of obtaining equation of state information for metals undergoing violent plastic deformation. In a typical experiment, millimetre thick metal samples are subjected to pressures on the order of 10 - 102 GPa, while the yield strength of the material can be as low as 10-2 GPa. The analysis of such experiments has so far neglected the effect of shear strength, instead treating the highly plasticised metal as an inviscid compressible fluid. However making this approximation belies the basic elastic nature of a solid object. A more accurate method should strive to incorporate the small but measurable effects of shear strength. Here we present a one-dimensional mathematical model for elastoplasticity at high stress which allows for both compressibility and the shear strength of the material. In the limit of zero yield stress this model reproduces the hydrodynamic models currently used to analyse ICEs. Numerical solutions of the governing equations will then be presented for problems relevant to ICEs in order to investigate the effects of shear strength compared with a model based purely on hydrodynamics.

  6. Measurement of Shear-Strength in Quasi-Isentropic Loading

    NASA Astrophysics Data System (ADS)

    Rosenberg, Z.; Bourne, N. K.; Millett, J. C. F.

    2001-06-01

    Recent work has indicated that an FCC material loaded at lower strain rate can exhibit higher strength than one loaded under shock. This result is puzzling given the hardening mechanisms involving dislocation pile-up usually accepted as occurring during shock. The effect may be followed by loading to a shocked state and then ringing up on an isentrope so that the loading departs from the Hugoniot after the first bounce. As a means of observing the strength of a material the lateral stress in the sample may be monitored along with the longitudinal stress so allowing a direct measurement in uniaxial strain as the difference between these two values. This relies on the development of an analysis to convert the voltage recorded in the gauge to lateral stress that must be checked for the step loading. The materials that are tested are iron and copper that are representative of BCC and FCC materials to give an insight as to the mechanism responsible for the observed phenomena. A mechanism is suggested to explain observations.

  7. Mesoscale Modeling of LX-17 Under Isentropic Compression

    SciTech Connect

    Springer, H K; Willey, T M; Friedman, G; Fried, L E; Vandersall, K S; Baer, M R

    2010-03-06

    Mesoscale simulations of LX-17 incorporating different equilibrium mixture models were used to investigate the unreacted equation-of-state (UEOS) of TATB. Candidate TATB UEOS were calculated using the equilibrium mixture models and benchmarked with mesoscale simulations of isentropic compression experiments (ICE). X-ray computed tomography (XRCT) data provided the basis for initializing the simulations with realistic microstructural details. Three equilibrium mixture models were used in this study. The single constituent with conservation equations (SCCE) model was based on a mass-fraction weighted specific volume and the conservation of mass, momentum, and energy. The single constituent equation-of-state (SCEOS) model was based on a mass-fraction weighted specific volume and the equation-of-state of the constituents. The kinetic energy averaging (KEA) model was based on a mass-fraction weighted particle velocity mixture rule and the conservation equations. The SCEOS model yielded the stiffest TATB EOS (0.121{micro} + 0.4958{micro}{sup 2} + 2.0473{micro}{sup 3}) and, when incorporated in mesoscale simulations of the ICE, demonstrated the best agreement with VISAR velocity data for both specimen thicknesses. The SCCE model yielded a relatively more compliant EOS (0.1999{micro}-0.6967{micro}{sup 2} + 4.9546{micro}{sup 3}) and the KEA model yielded the most compliant EOS (0.1999{micro}-0.6967{micro}{sup 2}+4.9546{micro}{sup 3}) of all the equilibrium mixture models. Mesoscale simulations with the lower density TATB adiabatic EOS data demonstrated the least agreement with VISAR velocity data.

  8. Isotherms Reduced from Isentropes and Hugoniots up to Several 100 GPa

    SciTech Connect

    Chijioke, Akobuije D.; Nellis, W. J.; Silvera, Isaac F.

    2006-07-28

    We have derived 300-K isotherms for static pressures as high as 300 GPa for Al, Cu, Ta and W. These isotherms are state-of-the-art equation-of-state (EOS) standards to calibrate the shift of the ruby fluorescence line as a function of pressure in diamond anvil cells (DACs). Recent measurements by Dewaele et al up to pressures of about 150 GPa in DACs motivated derivation of these isotherms. All experimental data used in this analysis were published previously. Hugoniot data are reduced to isotherms using thermal pressures calculated with mean field potential (MFP) theory and, for the first time, corrections were made using measured shock-induced strengths. Because this process has small systematic differences between different metal standards, it is important to obtain pressure by averaging results using many metals. Our purposes are (i) to give a brief description of how Hugoniots are reduced to isotherms and (ii) to articulate quasi-isentropes, Hugoniot data, and material strengths that need to be measured in the future for Al, Cu, Ta, W, Mo, Au, and Pt to improve the accuracies of the isotherms of these metals and to extend them to higher pressures. For calibration purposes, it is important that error bars be reported with such measurements.

  9. Use of Microwave Technique for Study of Isentropic Detonation Products Expansion

    NASA Astrophysics Data System (ADS)

    Bogdanov, Evgeny; Belsky, Vladimir; Zhernokletov, Mikhail; Mikhaylov, Anatoly; Rodionov, Alexey; Sedov, Alexander; Russian Federal Nuclear Center-Vniief 607190, Sarov, Nizhniy Novgorod Reg., Russia Team

    2013-06-01

    Application of the microwave technique for research of explosives and their detonation products can give a number of advantages as compared to the other experimental techniques. This technique makes it possible to perform a continuous recording of the shock and detonation waves motion directly in explosive. A significant advantage of the technique consists in absence of influence on investigated process, because there are no any sensors, optic fiber etc. in an explosive volume. The microwave technique was used for isentropic detonation products expansion study of HMX/TATB-based explosive compound. For determination of states on the expansion adiabat of detonation products, the experimental series was conducted. In these experiments we recorded time dependences of the shock wave velocities in dielectric microwave-transparent barriers, which were in contact with explosive samples. A low power 94 GHz quadrature interferometer was used. The conducted experiments showed that the use of microwave technique gives a big amount of interesting experimental data with a considerable research simplification.

  10. Adaptation of existing facilities to isentropic compression experiments

    SciTech Connect

    Tasker, Douglas G; Mielke, Charles H; Rodriguez, George; Rickel, Dwight G

    2011-01-07

    We demonstrate that the established pulsed power infrastructure at the National High Magnetic Field Laboratory - Pulsed Field Facility (NHMFL-PFF) at the Los Alamos National Laboratory can be adapted to obtain high quality isentropic compression experiment (ICE) data on materials in extreme conditions of dynamic high pressure. Experiments utilized a single-turn magnet pulsed power system at the NHMFL-PFF that was originally designed to measure actinide samples in extremes of high magnetic field (to 300 Tesla). A simple modification to the single-turn magnet has converted it to a fast turnaround dynamic high pressure measurement system. This paper details the work done including important background details that indicate that much more can be accomplished with optimization of the load characteristics in terms of ultimate peak pressures. To match the rise time of the NHMFL capacitor bank ({approx}2 {mu}s versus {approx}0.5 {mu}s for the Sandia Z-machine) the sample dimensions can be relatively large, i.e., up to 5 mm thickness. The maximum stresses are {approx}50GPa (0.5 Mbar) at the maximum bank voltage (60 kV) and higher pressures may be possible if the sample is tamped. For the design and predictions of performance of the NHMFL-ICE experiment it is important to have good predictive models. A SPICE code simulation was chosen to model all aspects of the experiment, electrical and physical. To this end, accurate dynamic load models were developed to simulate the compression and expansion of the dynamic load at high pressures using shock physics principles. A series experiments have been performed which demonstrated the feasibility of the NHMFL-ICE technique. The results will be shown and discussed. The NHMFL-ICE technique is an excellent method for measuring equations of state (EOS) at megabar pressures. Because a complete EOS can be obtained in one experiment from zero to the peak pressure, and because many shots can be fired in one day, the technique promises to

  11. Isentropic compression of metals, at multi-megabar pressures, using high explosive pulsed power

    SciTech Connect

    Tasker, D. G.; Goforth, J. H.; King, J. C.; Martinez, E. C.; Oona, H.; Sena, F. C.; Reisman, D. B.; Cauble, R. C.

    2001-01-01

    Accurate, ultra-high pressure isentropic equation of state (EOS) data, are required for a variety of applications and materials. Asay reported a new method to obtain these data using pulsed magnetic loading on the Sandia Z-machine. Fast rising current pulses (risetimes from 100 to 30011s) at current densities exceeding many MNcm, create continuous magnetic loading up to a few Mbar. As part of a collaborative effort between the Los Alamos and Lawrence Livermore National Laboratories we are adapting our high explosive pulsed power (HEPP) methods to obtain isentropic EOS data with the Asay technique. This year we plan to obtain isentropic EOS data for copper and tantalum at pressures up to -2 Mbar; eventually we hope to reach several tens of Mbar. We will describe the design of the HEPP systems and show out attempts to obtain EOS data to date.

  12. Shock waves and drag in the numerical calculation of isentropic transonic flow

    NASA Technical Reports Server (NTRS)

    Steger, J. L.; Baldwin, B. S.

    1972-01-01

    Properties of the shock relations for steady, irrotational, transonic flow are discussed and compared for the full and approximate governing potential in common use. Results from numerical experiments are presented to show that the use of proper finite difference schemes provide realistic solutions and do not introduce spurious shock waves. Analysis also shows that realistic drags can be computed from shock waves that occur in isentropic flow. In analogy to the Oswatitsch drag equation, which relates the drag to entropy production in shock waves, a formula is derived for isentropic flow that relates drag to the momentum gain through an isentropic shock. A more accurate formula for drag, based on entropy production, is also derived, and examples of wave drag evaluation based on these formulas are given and comparisons are made with experimental results.

  13. Thin Foil Acceleration Method for Measuring the Unloading Isentropes of Shock-Compressed Matter

    SciTech Connect

    Asay, J.R.; Chhabildas, L.C.; Fortov, V.E.; Kanel, G.I.; Khishchenko, K.V.; Lomonosov, I.V.; Mehlhorn, T.; Razorenov, S.V.; Utkin, A.V.

    1999-07-21

    This work has been performed as part of the search for possible ways to utilize the capabilities of laser and particle beams techniques in shock wave and equation of state physics. The peculiarity of these techniques is that we have to deal with micron-thick targets and not well reproducible incident shock wave parameters, so all measurements should be of a high resolution and be done in one shot. Besides the Hugoniots, the experimental basis for creating the equations of state includes isentropes corresponding to unloading of shock-compressed matter. Experimental isentrope data are most important in the region of vaporization. With guns or explosive facilities, the unloading isentrope is recovered from a series of experiments where the shock wave parameters in plates of standard low-impedance materials placed behind the sample are measured [1,2]. The specific internal energy and specific volume are calculated from the measured p(u) release curve which corresponds to the Riemann integral. This way is not quite suitable for experiments with beam techniques where the incident shock waves are not well reproducible. The thick foil method [3] provides a few experimental points on the isentrope in one shot. When a higher shock impedance foil is placed on the surface of the material studied, the release phase occurs by steps, whose durations correspond to that for the shock wave to go back and forth in the foil. The velocity during the different steps, connected with the knowledge of the Hugoniot of the foil, allows us to determine a few points on the isentropic unloading curve. However, the method becomes insensitive when the low pressure range of vaporization is reached in the course of the unloading. The isentrope in this region can be measured by recording the smooth acceleration of a thin witness plate foil. With the mass of the foil known, measurements of the foil acceleration will give us the vapor pressure.

  14. Results of explosively-driven isentropic compression experiments (HEPP-ICE)

    SciTech Connect

    Tasker, D. G.; Goforth, J. H.; Oona, H.; Rigg, P. A.; Dennis-Koller, D.; King, J. C.; Torres, D. T.; Herrera, D. H.; Sena, F. C.; Abeyta, F. G.; Tabaka, L. J.

    2004-01-01

    Using the Los Alamos high explosive pulsed power (HEPP) system, isentropic equation of state (EOS) data may be obtained for a wide range of materials. Current pulses with risetimes of {approx}500 ns and current densities exceeding 400 MA/m, create continuous magnetic loading of samples at megabar pressures. We will summarize the technique and the problems that had to be overcome to perform the HEPP-ICE experiments at these pressures. We will then present our EOS results obtained with the conventional Lagrangian analysis and the Hayes 'Backward' integration method, and compare the data with the published principal isentrope of OFHC copper.

  15. Laser driven quasi-isentropic compression experiments (ICE) for dynamically loading materials at high strain rates

    SciTech Connect

    Smith, R; Eggert, J; Celliers, P; Jankowski, A; Lorenz, T; Moon, S; Edwards, M J; Collins, G

    2006-03-30

    We demonstrate the recently developed technique of laser driven isentropic compression (ICE) for dynamically compressing Al samples at high loading rates close to the room temperature isentrope and up to peak stresses above 100GPa. Upon analysis of the unloading profiles from a multi-stepped Al/LiF target a continuous path through Stress-Density space may be calculated. For materials with phase transformations ramp compression techniques reveals the location of equilibrium phase boundaries and provide information on the kinetics of the lattice re-ordering.

  16. User manual for INVICE 0.1-beta : a computer code for inverse analysis of isentropic compression experiments.

    SciTech Connect

    Davis, Jean-Paul

    2005-03-01

    INVICE (INVerse analysis of Isentropic Compression Experiments) is a FORTRAN computer code that implements the inverse finite-difference method to analyze velocity data from isentropic compression experiments. This report gives a brief description of the methods used and the options available in the first beta version of the code, as well as instructions for using the code.

  17. DYNAMIC RESPONSE OF SINGLE CRYSTALLINE COPPER SUBJECTED TO QUASI-ISENTROPIC, GAS-GUN DRIVEN LOADING

    SciTech Connect

    Jarmakani, H; Mc Naney, J M; Schneider, M S; Cao, B Y; Orlikowski, D; Nguyen, J H; Kad, B; Meyers, M A

    2005-11-02

    A transmission electron microscopy study of quasi-isentropic gas-gun loading (peak pressures between 18 GPa and 52 GPa) of [001] monocrystalline copper was carried out. The defect substructures at these different pressures were analyzed. Current experimental evidence suggests a deformation substructure that transitions from slip to twinning, where twinning occurs at the higher pressures ({approx}52 GPa), and heavily dislocated laths and dislocation cells take place at the intermediate and lower pressures. Evidence of stacking faults at the intermediate pressures was also found. Dislocation cell sizes decreased with increasing pressure and increased with distance away from the surface of impact. The results from the quasi-isentropic experiments are compared with that of flyer-plate and laser shock experiments carried out by Cao et al. [1] and Schneider et al. [2], respectively. The Preston-Tonks-Wallace and Zerilli-Armstrong constitutive descriptions are used to model both isentropic and shock compression experiments and predict the pressure at which the slip-twinning transition occurs in both cases. Both models predict a higher transition for isentropic then for shock experiments, and indeed, that twinning should not take place in the ICE experiments at the pressures investigated.

  18. Optimization of current waveform tailoring for magnetically driven isentropic compression experiments

    NASA Astrophysics Data System (ADS)

    Waisman, E. M.; Reisman, D. B.; Stoltzfus, B. S.; Stygar, W. A.; Cuneo, M. E.; Haill, T. A.; Davis, J.-P.; Brown, J. L.; Seagle, C. T.; Spielman, R. B.

    2016-06-01

    The Thor pulsed power generator is being developed at Sandia National Laboratories. The design consists of up to 288 decoupled and transit time isolated capacitor-switch units, called "bricks," that can be individually triggered to achieve a high degree of pulse tailoring for magnetically driven isentropic compression experiments (ICE) [D. B. Reisman et al., Phys. Rev. Spec. Top.-Accel. Beams 18, 090401 (2015)]. The connecting transmission lines are impedance matched to the bricks, allowing the capacitor energy to be efficiently delivered to an ICE strip-line load with peak pressures of over 100 GPa. Thor will drive experiments to explore equation of state, material strength, and phase transition properties of a wide variety of materials. We present an optimization process for producing tailored current pulses, a requirement for many material studies, on the Thor generator. This technique, which is unique to the novel "current-adder" architecture used by Thor, entirely avoids the iterative use of complex circuit models to converge to the desired electrical pulse. We begin with magnetohydrodynamic simulations for a given material to determine its time dependent pressure and thus the desired strip-line load current and voltage. Because the bricks are connected to a central power flow section through transit-time isolated coaxial cables of constant impedance, the brick forward-going pulses are independent of each other. We observe that the desired equivalent forward-going current driving the pulse must be equal to the sum of the individual brick forward-going currents. We find a set of optimal brick delay times by requiring that the L2 norm of the difference between the brick-sum current and the desired forward-going current be a minimum. We describe the optimization procedure for the Thor design and show results for various materials of interest.

  19. Optimization of current waveform tailoring for magnetically driven isentropic compression experiments

    SciTech Connect

    Waisman, E. M.; Reisman, D. B.; Stoltzfus, B. S.; Stygar, W. A.; Cuneo, M. E.; Haill, T. A.; Davis, J.-P.; Brown, J. L.; Seagle, C. T.; Spielman, R. B.

    2016-06-15

    The Thor pulsed power generator is being developed at Sandia National Laboratories. The design consists of up to 288 decoupled and transit time isolated capacitor-switch units, called “bricks,” that can be individually triggered to achieve a high degree of pulse tailoring for magnetically driven isentropic compression experiments (ICE) [D. B. Reisman et al., Phys. Rev. Spec. Top.–Accel. Beams 18, 090401 (2015)]. The connecting transmission lines are impedance matched to the bricks, allowing the capacitor energy to be efficiently delivered to an ICE strip-line load with peak pressures of over 100 GPa. Thor will drive experiments to explore equation of state, material strength, and phase transition properties of a wide variety of materials. We present an optimization process for producing tailored current pulses, a requirement for many material studies, on the Thor generator. This technique, which is unique to the novel “current-adder” architecture used by Thor, entirely avoids the iterative use of complex circuit models to converge to the desired electrical pulse. We begin with magnetohydrodynamic simulations for a given material to determine its time dependent pressure and thus the desired strip-line load current and voltage. Because the bricks are connected to a central power flow section through transit-time isolated coaxial cables of constant impedance, the brick forward-going pulses are independent of each other. We observe that the desired equivalent forward-going current driving the pulse must be equal to the sum of the individual brick forward-going currents. We find a set of optimal brick delay times by requiring that the L{sub 2} norm of the difference between the brick-sum current and the desired forward-going current be a minimum. We describe the optimization procedure for the Thor design and show results for various materials of interest.

  20. Development and initial test of the University of Wisconsin global isentropic-sigma model

    NASA Technical Reports Server (NTRS)

    Zapotocny, Tom H.; Johnson, Donald R.; Reames, Fred M.

    1994-01-01

    The description of a global version of the University of Wisconsin (UW) hybrid isentropic-sigma (theta-sigma) model and the results from an initial numerical weather prediction experiment are presented in this paper. The main objectives of this initial test are to (1) discuss theta-sigma model development and computer requirements, (2) demonstrate the ability of the UW theta-sigma model for global numerical weather prediction using realistic orography and parameterized physical processes, and (3) compare the transport of an inert trace constituent against a nominally 'identical' sigma coordinate model. Initial and verifying data for the 5-day simulations presented in this work were supplied by the Goddard Earth Observing System (GEOS-1) data assimilation system. The time period studied is 1-6 February 1985. This validation experiment demonstrates that the global UW theta-sigma model produces a realistic 5-day simulation of the mass and momentum distributions when compared to both the identical sigma model and GEOS-1 verification. Root-mean-square errors demonstrate that the theta-sigma model is slightly more accurate than the nominally identical sigma model with respect to standard synoptic variables. Of particular importance, the UW theta-sigma model displays a distinct advantage over the conventional sigma model with respect to the prognostic simulation of inert trace constituent transport in amplifying baroclinic waves of the extratropics. This is especially true in the upper troposphere and stratosphere where the spatial integrity and conservation of an inert trace constituent is severely compromised in the sigma model compared to the theta-sigma model.

  1. Optimization of current waveform tailoring for magnetically driven isentropic compression experiments.

    PubMed

    Waisman, E M; Reisman, D B; Stoltzfus, B S; Stygar, W A; Cuneo, M E; Haill, T A; Davis, J-P; Brown, J L; Seagle, C T; Spielman, R B

    2016-06-01

    The Thor pulsed power generator is being developed at Sandia National Laboratories. The design consists of up to 288 decoupled and transit time isolated capacitor-switch units, called "bricks," that can be individually triggered to achieve a high degree of pulse tailoring for magnetically driven isentropic compression experiments (ICE) [D. B. Reisman et al., Phys. Rev. Spec. Top.-Accel. Beams 18, 090401 (2015)]. The connecting transmission lines are impedance matched to the bricks, allowing the capacitor energy to be efficiently delivered to an ICE strip-line load with peak pressures of over 100 GPa. Thor will drive experiments to explore equation of state, material strength, and phase transition properties of a wide variety of materials. We present an optimization process for producing tailored current pulses, a requirement for many material studies, on the Thor generator. This technique, which is unique to the novel "current-adder" architecture used by Thor, entirely avoids the iterative use of complex circuit models to converge to the desired electrical pulse. We begin with magnetohydrodynamic simulations for a given material to determine its time dependent pressure and thus the desired strip-line load current and voltage. Because the bricks are connected to a central power flow section through transit-time isolated coaxial cables of constant impedance, the brick forward-going pulses are independent of each other. We observe that the desired equivalent forward-going current driving the pulse must be equal to the sum of the individual brick forward-going currents. We find a set of optimal brick delay times by requiring that the L2 norm of the difference between the brick-sum current and the desired forward-going current be a minimum. We describe the optimization procedure for the Thor design and show results for various materials of interest.

  2. Excess Volumes and Excess Isentropic Compressibilities of Binary Liquid Mixtures of Trichloroethylene with Esters at 303.15 K

    NASA Astrophysics Data System (ADS)

    Ramanaiah, S.; Rao, C. Narasimha; Nagaraja, P.; Venkateswarlu, P.

    2015-11-01

    Exces volumes, VE, and excess isentropic compressibilities, κSE, have been reported as a function of composition for binary liquid mixtures of trichloroethylene with ethyl acetate, n-propyl acetate, and n-butyl acetate at 303.15 K. Isentropic compressibilities are calculated using measured sound speeds and density data for pure components and for binary mixtures. Excess volumes and excess isentropic compressibilities are found to be negative for the three systems studied over the entire composition range at 303.15 K, whereas these values become more negative with an increase of carbon chain length. The results are discussed in terms of intermolecular interactions between unlike molecules.

  3. Isentropic Compression up to 200 KBars for LX 04, Numerical Simulations and Comparison with Experiments

    SciTech Connect

    Lefrancois, A.; Hare, D.; L'Eplattenier, P.; Burger, M.

    2006-02-13

    Isentropic compression experiments and numerical simulations on LX-04 (HMX / Viton 85/15) were performed respectively at Z accelerator facility from Sandia National Laboratory and at Lawrence Livermore National Laboratory in order to study the isentrope and associated Hugoniot of this HE. 2D and 3D configurations have been calculated here to test the new beta version of the electromagnetism package coupled with the dynamics in Ls-Dyna and compared with the ICE Z shot 1067 on LX 04. The electromagnetism module is being developed in the general-purpose explicit and implicit finite element program LS-DYNA{reg_sign} in order to perform coupled mechanical/thermal/electromagnetism simulations. The Maxwell equations are solved using a Finite Element Method (FEM) for the solid conductors coupled with a Boundary Element Method (BEM) for the surrounding air (or vacuum). More details can be read in the references.

  4. Isentropic Compression with a Rectangular Configuration for Tungstene and Tantalum, Computations and Comparison with Experiments

    SciTech Connect

    Lefrancois, A.; Reisman, D. B.; Bastea, M.; L'Eplattenier, P.; Burger, M.

    2006-02-13

    Isentropic compression experiments and numerical simulations on metals are performed at Z accelerator facility from Sandia National Laboratory and at Lawrence Livermore National Laboratory in order to study the isentrope, associated Hugoniot and phase changes of these metals. 3D configurations have been calculated here to benchmark the new beta version of the electromagnetism package coupled with the dynamics in Ls-Dyna and compared with the ICE Z shots 1511 and 1555. The electromagnetism module is being developed in the general-purpose explicit and implicit finite element program LS-DYNA{reg_sign} in order to perform coupled mechanical/thermal/electromagnetism simulations. The Maxwell equations are solved using a Finite Element Method (FEM) for the solid conductors coupled with a Boundary Element Method (BEM) for the surrounding air (or vacuum). More details can be read in the references.

  5. Electrophysical properties of water and ice under isentropic compression to megabar pressures

    NASA Astrophysics Data System (ADS)

    Belov, S. I.; Boriskov, G. V.; Bykov, A. I.; Dolotenko, M. I.; Egorov, N. I.; Korshunov, A. S.; Kudasov, Yu. B.; Makarov, I. V.; Selemir, V. D.; Filippov, A. V.

    2017-02-01

    The relative permittivity and specific conductivity of water and ice are measured under isentropic compression to pressures above 300 GPa. Compression is initiated by a pulse of an ultrahigh magnetic field generated by an MK-1 magnetocumulative generator. The sample is placed in a coaxial compression chamber with an initial volume of about 40 cm3. The complex relative permittivity was measured by a fast-response reflectometer at a frequency of about 50 MHz. At the compression of water, its relative permittivity increases to ɛ = 350 at a pressure of 8 GPa, then drops sharply to ɛ = 140, and further decreases smoothly. It is shown that measurements of the relative permittivity under isentropic compression make it possible to determine interfaces between ordered and disordered phases of water and ice, as well as to reveal features associated with a change in the activation energy of defects.

  6. Isentropic Compression Loading of HMX and the Pressure-induced Phase Transition at 27 GPa

    SciTech Connect

    Hare, D E; Reisman, D B; Dick, J J; Forbes, J W

    2004-02-25

    The 27 GPa pressure-induced epsilon-phi phase transition in HMX is explored using the Isentropic Compression Experiment (ICE) technique at the Sandia National Laboratories Z-machine facility. Our data indicate that this phase transition is sluggish and if it does occur to any extent under the time scales (200-500 ns) and strain rates (5 x 10{sup 5}) typical of ICE loading conditions, the amount of conversion is small.

  7. Isentropic Analysis and Interpretation: Operational Applications to Synoptic and Mesoscale Forecast Problems. Revision

    DTIC Science & Technology

    1989-05-01

    have been discussed by Saucier (1955), Bleck (1973), Uccellini (1976), Wilson (1985), and Moore ( 1985 ). These advantages include: (1) Over synoptic...of strong convective instability. As a follow-up to the previous study, Moore ( 1985 ) expanded on the concepts presented by the above authors. He...section depicted in Figure 31b ( Moore , 1985 ). % 30%________________ I Figure 31b. Isentropic cross section for 1700 GMT 10 April 1979. The solid

  8. Electronic excitation and isentropic coefficients of high temperature planetary atmosphere plasmas

    SciTech Connect

    Colonna, Gianpiero; Capitelli, Mario

    2012-07-15

    In this paper, we have discussed the effects of electronically excited states of atomic species in affecting the isentropic coefficients of plasmas, focusing on mixtures representing the atmospheres of Jupiter, Mars, and Earth. General behaviors have been rationalized on the basis of simplified approaches. The contribution of the electronically excited states has been evidenced by comparing results obtained considering only the ground state and those obtained using either Fermi or Griem cutoff criteria.

  9. Isentropic Compression Studies at the Los Alamos National High Magnetic Field Laboratory

    DTIC Science & Technology

    2011-06-01

    actinide samples in extremes of high magnetic field (to 300 Tesla) [1, 2]. A simple modification to the single-turn magnet has converted it to a fast...Isentropic Compression Studies At The Los Alamos National High Magnetic Field Laboratory 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT ...Laboratory (NHMFL) at Los Alamos was originally designed to study actinide samples in extremes of high magnetic field (to 300 Tesla) [1, 2]. A simple

  10. Using DAO Model Potential Vorticities for Estimating Isentropic Cross-Tropopause Ozone Fluxes

    NASA Astrophysics Data System (ADS)

    Jing, P.; Cunnold, D. M.

    2002-12-01

    The GEOS-1 datasets for the year of 1990 from the Data Assimilation Office (DAO) at NASA's Goddard Space Flight Center (GSFC) are used to estimate the isentropic stratosphere-troposphere exchange of ozone using the Contour Advection technique. The procedure involves using DAO potential vorticities (PV) to define the dynamical tropopause and to generate the global distributions of ozone from the monthly relationships between the DAO PV and the SAGE version 6.1 ozone. It is demonstrated that the inferred PV-O3 relationship produces ozone profiles which are in good agreement with ozonesonde measurements with a standard deviation of about 0.07 ppmv. According to Hoerling, et al (1991), 3.5 PVU (1 PVU=10-6 K m2 kg-1 s-1) represents an optimal definition of the tropopause outside the tropics for the ECWMF dataset in January, 1979. This study extends the analysis of the 3.5 PVU tropopause to all seasons and shows that the 3.5 PVU tropopause is generally consistent with the thermal tropopause in mid-latitudes. Using the 3.5 PVU tropopause and ozone produced by the PV-O3 relationship, we calculate the ozone fluxes across the tropopause along four isentropic layers (335 K, 345 K, 355 K and 365 K) by applying Contour Advection. The total annual stratosphere-to-troposphere isentropic ozone flux for the four layers in the NH is 191 Tg/yr (1 Tg=10{9} kg). It is approximately 60% of the total annual stratospheric-to-troposphere ozone transport (335 Tg/yr in the NH) calculated from 3-D general circulation models (Crutzen, et al, 1995). We conclude that the potential vorticities obtained from the DAO assimilation model results well represent the tropopause when the value of 3.5 PVU is used and they produce a robust relationship with ozone which makes it feasible to estimate the isentropic cross-tropopause transport of ozone globally.

  11. Isentropic expansion of copper plasma in Mbar pressure range at "Luch" laser facility

    NASA Astrophysics Data System (ADS)

    Bel'kov, S. A.; Derkach, V. N.; Garanin, S. G.; Mitrofanov, E. I.; Voronich, I. N.; Fortov, V. E.; Levashov, P. R.; Minakov, D. V.

    2014-01-01

    We present experimental results on thermodynamic properties of dense copper plasma in Mbar pressure range. The laser facility "Luch" with laser intensity 1014 W/cm2 is used to compress copper up to ˜8 Mbar by a strong shock wave; subsequent expansion of copper plasma into Al, Ti, Sn allows us to obtain release isentropes of copper by the impedance-matching method. A theoretical analysis and quantum simulations show that in our experiments strongly coupled quantum plasma is generated.

  12. Influence of isentropic transport on seasonal ozone variations in the lower stratosphere and subtropical upper troposphere

    NASA Technical Reports Server (NTRS)

    Jing, P.; Cunnold, D. M.; Yang, E.-S.; Wang, H.-J.

    2005-01-01

    The isentropic cross-tropopause ozone transport has been estimated in both hemispheres in 1999 based on the potential vorticity mapping of Stratospheric Aerosol and Gas Experiment 11 ozone measurements and contour advection calculations using the NASA Goddard Space Flight Center Global and Modeling Assimilation Office analysis. The estimated net isentropic stratosphere-to-troposphere ozone flux is approx.118 +/- 61 x 10(exp9)kg/yr globally within the layer between 330 and 370 K in 1999; 60% of it is found in the Northern Hemisphere, and 40% is found in the Southern Hemisphere. The monthly average ozone fluxes are strongest in summer and weakest in winter in both hemispheres. The seasonal variations of ozone in the lower stratosphere (LS) and upper troposphere (UT) have been analyzed using ozonesonde observations from ozonesonde stations in the extratropics and subtropics, respectively. It is shown that observed ozone levels increase in the UT over subtropical ozonesonde stations and decrease in the LS over extratropical stations in late spring/early summer and that the ozone increases in the summertime subtropical UT are unlikely to be explained by photochemical ozone production and diabatic transport alone. We conclude that isentropic transport is a significant contributor to ozone levels in the subtropical upper troposphere, especially in summer.

  13. Quasigeostrophic vertical motions diagnosed from along- and cross-isentrope components of the Q vector

    NASA Technical Reports Server (NTRS)

    Keyser, Daniel; Schmidt, Brian D.; Duffy, Dean G.

    1992-01-01

    In a recent paper on the kinematics of frontogenesis, Keyser et al. (1988) conjectured that partitioning the Q vector into along- and cross-isentrope components yields vertical-motion patterns that are respectively cellular and banded: the former on the scale of the baroclinic disturbance, and the latter on the scale of the embedded frontal zones. This conjecture is examined diagnostically through solution of the quasi-geostrophic omega equation, using the output from a nearly adiabatic and frictionless f-plane primitive equation channel model of the evolution of a baroclinic disturbance to finite amplitude. The results of the present study support the proposed conjecture, suggesting the following interpretation of the characteristic comma structure of the vertical-motion field in midlatitude baroclinic disturbances: the dipole is associated with the along-isentrope component of the Q vector, reflecting the wavelike pattern in the potential temperature field within the baroclinic disturbance; the asymmetries are associated with the cross-isentrope component of the Q vector, reflecting the presence of frontal zones within the baroclinic disturbance.

  14. Advances in Isentropic Compression Experiments (ICE) Using High Explosive Pulsed Power

    NASA Astrophysics Data System (ADS)

    Tasker, D. G.; Goforth, J. H.; Oona, H.; Fowler, C. M.; King, J. C.; Herrera, D.; Torres, D.

    2004-07-01

    We are developing a prototype high explosive pulsed power (HEPP) system to obtain isentropic Equation of State (EOS) data with the Asay technique. Our prototype system comprises a flat-plate explosive driven magnetic flux compression generator (FCG), an explosively formed fuse (EFF) opening switch, and a series of explosively-actuated closing switches. The FCG is capable of producing ˜10 MA into suitable loads, and, at a length of 216 mm, the EFF will sustain voltages in excess of 200 kV. The load has an inductance of ˜3 to 10 nH, allowing up to ˜7 MA to be delivered in times of ˜0.5 μs. This prototype will produce isentropic compression profiles in excess of 2 Mbar in a material such as tungsten. We will obtain isentropic EOS data for copper at pressures up to ˜1.5 Mbar with the prototype system, immediately after this conference; eventually we plan to reach several tens of Mbar with larger, more advanced systems.

  15. Observations and Modeling of Composition of Upper Troposphere/Lower Stratosphere (UTILS): Isentropic Mixing Events and Morphology of HNO3 as Observed by HIRDLS and Comparison with Results from Global Modeling Initiative

    NASA Technical Reports Server (NTRS)

    Rodriquez, J. M.; Douglass, A.R.; Yoshida, Y.; Strahan, S.; Duncan, B.; Olsen, M.; Gille, J.; Yudin, V.; Nardi, B.

    2008-01-01

    isentropic exchange of air masses between the tropical upper troposphere and mid-latitude lowermost stratosphere (the so-called "middle world") is an important pathway for stratospheric-tropospheric exchange. A seasonal, global view of this process has been difficult to obtain, in part due to the lack of the vertical resolution in satellite observations needed to capture the laminar character of these events. Ozone observations at a resolution of about 1 km from the High Resolution Dynamic Limb Sounder (HIRDLS) on NASA's Aura satellite show instances of these intrusions. Such intrusions should also be observable in HN03 observations; however, the abundances of nitric acid could be additionally controlled by chemical processes or incorporation and removal into ice clouds. We present a systematic examination of the HIRDLS data on O3 and HNO3 to determine the seasonal and spatial characteristics of the distribution of isentropic intrusions. At the same time, we compare the observed distributions with those calculated by the Global Modeling Initiative combined tropospheric-stratospheric model, which has a vertical resolution of about I km. This Chemical Transport Model (CTM) is driven by meteorological fields obtained from the GEOS-4 system of NASA/Goddard Global Modeling and Assimilation Office (GMAO), for the Aura time period, at a vertical resolution of about 1 km. Such comparison brings out the successes and limitations of the model in representing isentropic stratospheric-tropospheric exchange, and the different processes controlling HNO3 in the UTAS.

  16. Shock-adiabatic to quasi-isentropic compression of warm dense helium up to 150 GPa

    NASA Astrophysics Data System (ADS)

    Zheng, J.; Chen, Q. F.; Gu, Y. J.; Li, J. T.; Li, Z. G.; Li, C. J.; Chen, Z. Y.

    2017-06-01

    Multiple reverberation compression can achieve higher pressure, higher temperature, but lower entropy. It is available to provide an important validation for the elaborate and wider planetary models and simulate the inertial confinement fusion capsule implosion process. In the work, we have developed the thermodynamic and optical properties of helium from shock-adiabatic to quasi-isentropic compression by means of a multiple reverberation technique. By this technique, the initial dense gaseous helium was compressed to high pressure and high temperature and entered the warm dense matter (WDM) region. The experimental equation of state (EOS) of WDM helium in the pressure-density-temperature (P-ρ -T) range of 1 -150 GPa , 0.1 -1.1 g c m-3 , and 4600-24 000 K were measured. The optical radiations emanating from the WDM helium were recorded, and the particle velocity profiles detecting from the sample/window interface were obtained successfully up to 10 times compression. The optical radiation results imply that dense He has become rather opaque after the 2nd compression with a density of about 0.3 g c m-3 and a temperature of about 1 eV. The opaque states of helium under multiple compression were analyzed by the particle velocity measurements. The multiple compression technique could efficiently enhanced the density and the compressibility, and our multiple compression ratios (ηi=ρi/ρ0,i =1 -10 ) of helium are greatly improved from 3.5 to 43 based on initial precompressed density (ρ0) . For the relative compression ratio (ηi'=ρi/ρi -1) , it increases with pressure in the lower density regime and reversely decreases in the higher density regime, and a turning point occurs at the 3rd and 4th compression states under the different loading conditions. This nonmonotonic evolution of the compression is controlled by two factors, where the excitation of internal degrees of freedom results in the increasing compressibility and the repulsive interactions between the

  17. Numerical modeling of the atmosphere with an isentropic vertical coordinate

    NASA Technical Reports Server (NTRS)

    Hsu, Yueh-Jiuan G.; Arakawa, Akio

    1990-01-01

    A theta-coordinate model simulating the nonlinear evolution of a baroclinic wave is presented. In the model, vertical discretization maintains important integral constraints such as conservation of the angular momentum and total energy. A massless-layer approach is used in the treatment of the intersections of coordinate surfaces with the lower boundary. This formally eliminates the intersection problem, but raises other computational problems. Horizontal discretization of the continuity and momentum equations in the model are designed to overcome these problems. Selected results from a 10-day integration with the 25-layer, beta-plane version of the model are presented. It is concluded that the model can simulate the nonlinear evolution of a baroclinic wave and associated dynamical processes without major computational difficulties.

  18. Accessing Ultra-High Pressure, Quasi-Isentropic States of Matter

    SciTech Connect

    Lorenz, K T; Edwards, M J; Glendinning, S G; Ho, D D; Jankowski, A F; McNaney, J; Pollaine, S M; Remington, B A

    2004-11-12

    A new approach to the study of material strength of metals at extreme pressures has been developed on the Omega laser, using a ramped plasma piston drive. The laser drives a shock through a solid plastic reservoir that unloads at the rear free surface, expands across a vacuum gap, and stagnates on the metal sample under study. This produces a gently increasing ram pressure, compressing the sample nearly isentropically. The peak pressure on the sample, inferred from VISAR measurements of velocity, can be varied by adjusting the laser energy and pulse length, gap size, and reservoir density, and obeys a simple scaling relation. In an important application, using in-flight x-ray radiography, the material strength of solid-state samples at high pressure can be inferred by measuring the reductions in the growth rates (stabilization) of Rayleigh-Taylor (RT) unstable interfaces. This paper reports the first attempt to use this new laser-driven, quasi-isentropic technique for determining material strength in high-pressure solids. Modulated foils of Al-6061-T6 were accelerated and compressed to peak pressures of 200 kbar. Modulation growth was recorded at a series of times after peak acceleration and well into the release phase. Fits to the growth data, using a Steinberg-Guinan (SG) constitutive strength model, give yield strengths 30% greater than those given by the nominal parameters for Al-6061-T6. Calculations indicate that the dynamic enhancement to the yield strength at 200 kbar is a factor of {approx}2.5x over the ambient yield strength of 2.9 kbar. Experimental designs based on this drive developed for the NIF laser, predict that solid-state samples can be quasi-isentropically driven to pressures an order of magnitude higher than on Omega--accessing new regimes of dense, high-pressure matter.

  19. Montgomery Potential and Wind Fields on Isentropic Surfaces from GPS Radio Occultation

    NASA Astrophysics Data System (ADS)

    Scherllin-Pirscher, Barbara; Steiner, Andrea; Kirchengast, Gottfried; Leroy, Stephen

    2015-04-01

    Atmospheric profiles from Global Positioning System (GPS) radio occultation (RO) measurements provide precise and accurate information on the thermal structure of the troposphere and lower stratosphere. Since altitude (and also geopotential height) is based on accurate knowledge of the position and velocity vectors of the transmitter and receiver satellites involved, it is possible to obtain highly resolved and accurate vertical information from RO. In this study we use observational data from 2007 to 2013 from the RO missions CHAMP, SAC-C, GRACE-A, and Formosat-3/COSMIC. Using potential temperature as the vertical coordinate we calculate monthly means of the Montgomery potential on isentropic surfaces from 300 K to 600 K (approximately 12 km to 24 km in altitude) with a horizontal resolution of 5° in latitude and 5° in longitude. Contours of the Montgomery potential on isentropic surfaces correspond to a stream-function for adiabatic, geostrophic flow. Subsequently we derive monthly mean geostrophic wind fields (outside the tropics) from sampling error-corrected fields of the Montgomery potential on isentropic surfaces. We find that these climatological RO wind fields clearly capture all of the main wind features with departures from analysis winds being, in general, smaller than 2 m s-1. Larger biases close to the subtropical jet and at high latitudes'biases rarely exceed 10 %'are caused by the geostrophic approximation. We present monthly mean wind fields, their annual cycle as well as inter-annual variability related to the El Niño-Southern Oscillation. This three-dimensional information of high quality from RO data can subsequently be utilized to investigate atmospheric dynamics close to the tropopause.

  20. On the reachable cycles via the unified perspective of cryocoolers. Part B: Cryocoolers with isentropic expanders

    SciTech Connect

    Maytal, Ben-Zion; Pfotenhauer, John M.

    2014-01-29

    Solvay, Stirling and Gifford-McMahon types of cryocoolers employ an isentropic expander which is their elementary mechanism for temperature reduction (following the unified model of cryocoolers as described in a previous paper, Part A). Solvay and Stirling cryocoolers are driven by a larger temperature reduction than that of the Gifford-McMahon cycle, for a similar compression ratio. These cryocoolers are compared from the view of the unified model, in terms of the lowest attainable temperature, compression ratio, the size of the interchanger and the applied heat load.

  1. On the reachable cycles via the unified perspective of cryocoolers. Part B: Cryocoolers with isentropic expanders

    NASA Astrophysics Data System (ADS)

    Maytal, Ben-Zion; Pfotenhauer, John M.

    2014-01-01

    Solvay, Stirling and Gifford-McMahon types of cryocoolers employ an isentropic expander which is their elementary mechanism for temperature reduction (following the unified model of cryocoolers as described in a previous paper, Part A). Solvay and Stirling cryocoolers are driven by a larger temperature reduction than that of the Gifford-McMahon cycle, for a similar compression ratio. These cryocoolers are compared from the view of the unified model, in terms of the lowest attainable temperature, compression ratio, the size of the interchanger and the applied heat load.

  2. Experimental measurement of the principal isentrope for aluminum 6061-T6 to 240 GPa.

    SciTech Connect

    Davis, Jean-Paul

    2005-02-01

    Using a magnetic pressure drive, an absolute measurement of stress and density along the principal compression isentrope is obtained for solid aluminum to 240 GPa. Reduction of the free-surface velocity data relies on a backward integration technique, with approximate accounting for unknown systematic errors in experimental timing. Maximum experimental uncertainties are {+-}4.7% in stress and {+-}1.4% in density, small enough to distinguish between different equation-of-state (EOS) models. The result agrees well with a tabular EOS that uses an empirical universal zero-temperature isotherm.

  3. Experimental measurement of the principal isentrope for aluminum 6061-T6 to 240 GPa.

    SciTech Connect

    Davis, Jean-Paul

    2006-02-01

    Using a magnetic pressure drive, an absolute measurement of stress and density along the principal compression isentrope is obtained for solid aluminum to 240 GPa. Reduction of the free-surface velocity data relies on a backward integration technique, with approximate accounting for unknown systematic errors in experimental timing. Maximum experimental uncertainties are +/-4.7% in stress and +/-1.4% in density, small enough to distinguish between different equation-of-state (EOS) models. The result agrees well with a tabular EOS that uses an empirical universal zero-temperature isotherm.

  4. Isentropic Compression Experiments Performed By LLNL On Energetic Material Samples Using The Z Accelerator

    SciTech Connect

    Vandersall, K S; Reisman, D B; Forbes, J W; Hare, D E; Garcia, F; Uphaus, T M; Elsholz, A J; Tarver, C M; Eggert, J H

    2007-10-25

    Several experiments have been conducted by LLNL researchers using isentropic compression experiments (ICE) on energetic materials as samples from Fiscal Year 2001 (FY01) to Fiscal Year 2005 (FY05). Over this span of time, advancements of the experimental techniques and modeling of the results have evolved to produce improved results. This report documents the experiments that have been performed, provides details of the results generated, and modeling and analysis advances to fully understand the results. Publications on the topics by the various principal investigators (PI's) are detailed in the Appendices for quick reference for the work as it progressed.

  5. Isentropic compressive wave generator impact pillow and method of making same

    DOEpatents

    Barker, Lynn M.

    1985-01-01

    An isentropic compressive wave generator and method of making same. The w generator comprises a disk or flat "pillow" member having component materials of different shock impedances formed in a configuration resulting in a smooth shock impedance gradient over the thickness thereof for interpositioning between an impactor member and a target specimen for producing a shock wave of a smooth predictable rise time. The method of making the pillow member comprises the reduction of the component materials to a powder form and forming the pillow member by sedimentation and compressive techniques.

  6. Nongeostrophic theory of zonally averaged circulation. II - Eliassen-Palm flux divergence and isentropic mixing coefficient

    NASA Technical Reports Server (NTRS)

    Yang, H.; Tung, K. K.; Olaguer, E.

    1990-01-01

    A diagnostic study of Eliassen-Palm flux divergence and isentropic mixing coefficient (Kyy) in the stratosphere is performed for different seasons and for both hemispheres, based on the nongeostrophic theory of zonally averaged circulation of Tung (1986). An easily implementable procedure is described which yields a Kyy field that is consistent with advective transport. It is shown that the resultant time- and space-varying structure of Kyy leads to improved simulation of stratospheric species whose distributions are affected by dynamical transport. In particular, it is shown that the simulation of nitric acid is more satisfactory than previous model calculations.

  7. DYNAMIC RESPONSE OF COPPER SUBJECTED TO QUASI-ISENTROPIC, GAS-GUN DRIVEN LOADING

    SciTech Connect

    Jarmakani, H; McNaney, J M; Schneider, M S; Orlikowski, D; Nguyen, J H; Kad, B; Meyers, M A

    2005-09-29

    A transmission electron microscopy study of quasi-isentropic high-pressure loading (peak pressures between 18 GPa and 52 GPa) of polycrystalline and monocrystalline copper was carried out. Deformation mechanisms and defect substructures at different pressures were analyzed. Current evidence suggests a deformation substructure consisting of twinning at the higher pressures and heavily dislocated laths and dislocation cells at the intermediate and lower pressures, respectively. Evidence of stacking faults at the intermediate pressures was also found. Dislocation cell sizes decreased with increasing pressure and increased with distance away from the surface of impact.

  8. Isentropic expansion of copper plasma in Mbar pressure range at “Luch” laser facility

    SciTech Connect

    Bel'kov, S. A.; Derkach, V. N.; Garanin, S. G.; Mitrofanov, E. I.; Voronich, I. N.; Fortov, V. E.; Levashov, P. R.; Minakov, D. V.

    2014-01-21

    We present experimental results on thermodynamic properties of dense copper plasma in Mbar pressure range. The laser facility “Luch” with laser intensity 10{sup 14} W/cm{sup 2} is used to compress copper up to ∼8 Mbar by a strong shock wave; subsequent expansion of copper plasma into Al, Ti, Sn allows us to obtain release isentropes of copper by the impedance–matching method. A theoretical analysis and quantum simulations show that in our experiments strongly coupled quantum plasma is generated.

  9. Isentropic compression of fused quartz and liquid hydrogen to several Mbar

    NASA Technical Reports Server (NTRS)

    Hawke, R. S.; Duerre, D. E.; Huebel, J. G.; Keeler, R. N.; Klapper, H.

    1972-01-01

    Models of the major planets are in part based on the equations of state of very compressible materials such as hydrogen and helium. A technique of isentropically compressing soft material to several Mbar and some preliminary results on fused quartz (silicon dioxide) and liquid hydrogen is described. Quartz was found to be an electrical non-conductor up to 5 Mbar and has a volume of about 0.15 cubic centimeters per gram at that pressure. Liquid hydrogen was found to have a volume of about 1 cm3/g at a pressure of about 2 Mbar. It was not determined if it was transformed into a metal.

  10. Isentropic compression of fused quartz and liquid hydrogen to several Mbar

    NASA Technical Reports Server (NTRS)

    Hawke, R. S.; Duerre, D. E.; Huebel, J. G.; Keeler, R. N.; Klapper, H.

    1972-01-01

    Models of the major planets are in part based on the equations of state of very compressible materials such as hydrogen and helium. A technique of isentropically compressing soft material to several Mbar and some preliminary results on fused quartz (silicon dioxide) and liquid hydrogen is described. Quartz was found to be an electrical non-conductor up to 5 Mbar and has a volume of about 0.15 cubic centimeters per gram at that pressure. Liquid hydrogen was found to have a volume of about 1 cm3/g at a pressure of about 2 Mbar. It was not determined if it was transformed into a metal.

  11. Condensed argon isentropic compression with ultrahigh magnetic field pressure: Results of the experiment. Post-shot report

    SciTech Connect

    1994-12-31

    The experiment on solid argon isentropic compression with MC-1 generator ultrahigh magnetic field pressure which was scheduled in VNIIEF-LANL subcontract, has initiated the condensed argon study at megabar pressures. The experiment has recorded the predicted argon compression by more than 5 times that, by the existing concepts, corresponds to 6 Mbar pressure. Thus, the main goals of the experiment were achieved: demonstration of the method`s possibilities and statement of the subsequent study. The isentropic compression device capabilities were shown, the basic characteristics of the isentropic compression and an initial parameters of the experimental facilities and techniques were defined, new information on the changed argon properties at 1 Mbar was obtained.

  12. Computer Programs for Calculating the Isentropic Flow Properties for Mixtures of R-134a and Air

    NASA Technical Reports Server (NTRS)

    Kvaternik, Raymond G.

    2000-01-01

    Three computer programs for calculating the isentropic flow properties of R-134a/air mixtures which were developed in support of the heavy gas conversion of the Langley Transonic Dynamics Tunnel (TDT) from dichlorodifluoromethane (R-12) to 1,1,1,2 tetrafluoroethane (R-134a) are described. The first program calculates the Mach number and the corresponding flow properties when the total temperature, total pressure, static pressure, and mole fraction of R-134a in the mixture are given. The second program calculates tables of isentropic flow properties for a specified set of free-stream Mach numbers given the total pressure, total temperature, and mole fraction of R-134a. Real-gas effects are accounted for in these programs by treating the gases comprising the mixture as both thermally and calorically imperfect. The third program is a specialized version of the first program in which the gases are thermally perfect. It was written to provide a simpler computational alternative to the first program in those cases where real-gas effects are not important. The theory and computational procedures underlying the programs are summarized, the equations used to compute the flow quantities of interest are given, and sample calculated results that encompass the operating conditions of the TDT are shown.

  13. Systematic approach to using isentropic stress reverberation techniques in approximating equation of state.

    PubMed

    Plume, Gifford; Rousseau, Carl-Ernst

    2015-03-01

    Isentropic stress reverberations are used to obtain multiple Hugoniot states from a single plate impact experiment using a layered plate geometry, where a low impedance inner layer is embedded within a high impedance bulk structure. The mathematical framework used in this technique uses the classical Rankine-Hugoniot equations in the method of impedance matching, where the bulk material is required to have a known Hugoniot. Factors including the wave velocities in the materials, input pulse duration, inner layer thickness, and diameter of the test samples affect the number of states that can be generated from a single experiment. Experiments using 6061 aluminum and polycarbonate, respectively, as the bulk material and inner layer, accurately generated six Hugoniot states for the polycarbonate. Experiments using A572 grade 50 structural steel as the bulk material accurately generated ten Hugoniot states for the polycarbonate. For each experiment, the method can be used to generate a Hugoniot equation defining the material response of the inner layer within the domain encompassed by the specific test. The method is also confined to the low to moderate stress regions, within which Hugoniot and isentropic representations of the material are almost identical.

  14. Density functional theory simulations of polyethylene: principal Hugoniot, specific heats, compression and release isentropes

    NASA Astrophysics Data System (ADS)

    Cochrane, K. R.; Desjarlais, M. P.; Mattsson, T. R.

    2011-06-01

    An accurate equation of state (EOS) for polyethylene is required in order to model high energy density experiments for CH2 densities above 1 g/cc, temperatures above 1 eV, and pressures above 1 Mbar. Density Functional Theory (DFT) based molecular dynamics has been established as a method capable of yielding high fidelity results for many materials at a wide range of pressures and temperatures and has recently been applied to complex polymers such as polyethylene. Using high density polyethylene as the reference state, we compute the principal Hugoniot to 350 GPa, compression isentrope, and several release isentropes from states on the principal Hugoniot. We also calculate the specific heat and the dissociation along the Hugoniot. Our simulation results are validated by comparing to experimental data and then used to construct a wide range EOS. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corp., a subsidiary of Lockheed Martin Corp., for the U.S. Department of Energy's National Nuclear Security Administration under Contract No. DE-AC04-94AL85000.

  15. On the Energy Dissipation Rate of Solutions to the Compressible Isentropic Euler System

    NASA Astrophysics Data System (ADS)

    Chiodaroli, Elisabetta; Kreml, Ondrej

    2014-07-01

    In this paper we extend and complement the results in Chiodaroli et al. (Global ill-posedness of the isentropic system of gas dynamics, 2014) on the well-posedness issue for weak solutions of the compressible isentropic Euler system in 2 space dimensions with pressure law p(ρ) = ρ γ , γ ≥ 1. First we show that every Riemann problem whose one-dimensional self-similar solution consists of two shocks admits also infinitely many two-dimensional admissible bounded weak solutions (not containing vacuum) generated by the method of De Lellis and Székelyhidi (Ann Math 170:1417-1436, 2009), (Arch Ration Mech Anal 195:225-260, 2010). Moreover we prove that for some of these Riemann problems and for 1 ≤ γ < 3 such solutions have a greater energy dissipation rate than the self-similar solution emanating from the same Riemann data. We therefore show that the maximal dissipation criterion proposed by Dafermos in (J Diff Equ 14:202-212, 1973) does not favour the classical self-similar solutions.

  16. Non-relativistic limits of rarefaction wave to the 1-D piston problem for the isentropic relativistic Euler equations

    NASA Astrophysics Data System (ADS)

    Ding, Min; Li, Yachun

    2017-08-01

    We consider the 1-D piston problem for the isentropic relativistic Euler equations when the total variations of the initial data and the speed of the piston are both sufficiently small. By a modified wave front tracking method, we establish the global existence of entropy solutions including a strong rarefaction wave without restriction on the strength. Meanwhile, we study the convergence of the entropy solutions to the corresponding entropy solutions of the classical non-relativistic isentropic Euler equations as the light speed c →+∞ .

  17. Tables of isentropic expansions of parahydrogen and related transport properties for total temperatures from 25 K to 300 K and for total pressures from 1 ATM to 10 ATM

    NASA Technical Reports Server (NTRS)

    Haut, R. C.; Adcock, J. B.

    1976-01-01

    The isentropic expansions of parahydrogen at various total pressures and total temperatures were numerically determined by iterating Mach number and by using a modified interval halving method. The calculated isentropic values and related properties are presented in tabulated form.

  18. Layering Principles from One Approach to Isentropic Analysis and Modeling of the Atmosphere

    NASA Astrophysics Data System (ADS)

    Fulker, D. W.

    2015-12-01

    Meteorologists often treat potential temperature (theta)—the temperature a parcel would have if moved adiabatically to the surface—as a vertical coordinate. The resulting layers (isentropes) are lagrangian-like. Bosart, in a 2002 tribute to Reed, writes "PV as a tracer [along isentropes] enabled Reed, Danielson … to adopt a Lagrangian perspective in studies of cyclogenesis and upper-level frontogenesis." Bosart also mentions Shapiro's work on clear-air turbulence and Bleck's modeling: "Bleck ... simulated cyclogenesis using a simple model [on] surfaces of constant potential temperature." From the author's work helping Bleck and Shapiro with isentropic analysis and modeling, the following principles are offered as potentially useful in defining reusable, consistent data layers across space and time in multiple domains. Monotonicity— Layers reflect transformed coordinates, mappable to/from elevation, hence strictly monotonic across the geographic domain. I.e., layers cannot intersect. Bleck devised an invertible algorithm mapping pressure along soundings to a coordinate resembling potential temperature (departing only to maintain monotonicity). A collection of these (at one observing time) is a sampled representation of the transform between (lat, lon, elev) and (lat, lon, theta). Suggested principle: Data layers possess, for a geographic sample set, invertible algorithms to map between elevation and a monotonic transform coordinate. Intralayer Interpolation — The transformed coordinate may need evaluation at points not in the sample set. The Bleck/Shapiro work showed how easily monotonicity is violated when gridding sample data. This problem was solved via another transform: interpolation on the log of layer differences (i.e., thickness). Suggested principle: Data layers possess a monotonicity-preserving algorithm to interpolate coordinate values to geographic points not in the sample set.Representation— The Bleck/Shapiro work entailed no data sharing

  19. Bulk Properties of Isentropic Mixing into the Tropics in the Lower Stratosphere

    NASA Technical Reports Server (NTRS)

    Minschwaner, K.; Dessler, A. E.; Elkins, J. W.; Volk, C. M.; Fahey, D. W.; Loewenstein, M.; Podolske, J. R.; Chan, K. R.; Roche, A. E.

    1996-01-01

    Timescales for mixing of midlatitude air into the tropical lower stratosphere are deduced from observations of long-lived tracers N2O and CCl3F. Bulk mixing between tropical and midlatitude regions is assumed to be isentropic and relatively slow compared with local mixing within each region. The mean value of the mixing timescale ranges from 12 to 18 months near 20 km. There is a tendency for shorter mixing times at higher and lower altitudes, although vertical profiles of mixing cannot be definitively established by the data. A more robust quantity is given by the fraction of midlatitude air entrained into the tropical upwelling region. Implied mixing fractions exceed 50% above 22 km.

  20. High strain rates effects in quasi-isentropic compression of solids

    SciTech Connect

    Ravelo, Ramon; Holian, Brad L; Germann, Timothy C

    2009-01-01

    We have performed large-scale molecular-dynamics (MD) simulations of shock loading and quasi-isentropic compression in defective copper crystals, modeling the interatomic interactions with an embedded-atom method potential. For samples with a relatively low density of pre-existing defects, the strain rate dependence of the flow stress follows a power law in the 10{sup 9}-10{sup 12} s{sup -1} regime with an exponent of 0.40. For initially damaged, isotropic crystals the flow stress exhibits a narrow linear region in strain rate, which then bends over at high strain rates in a manner reminiscent of shear thinning in fluids. The MD results can be described by a modification of Eyring's theory of Couette shear flow in fluids.

  1. A comparison of simulated precipitation by hybrid isentropic-sigma and sigma models

    NASA Technical Reports Server (NTRS)

    Johnson, Donald R.; Zapotocny, Tom H.; Reames, Fred M.; Wolf, Bart J.; Pierce, R. B.

    1993-01-01

    Simulations of dry and moist baroclinic development from 10- and 22-layer hybrid isentropic-sigma coordinate models are compared with those from 11-, 27-, and 35-layer sigma coordinate models. The ability of the models to transport water vapor and simulate equivalent potential temperature is examined. Predictions of the timing, location, and amount of precipitation are compared. Several analytical distributions of water vapor are specified initially. It is shown that when the relative humidity is vertically uniform through a substantial extent of the atmosphere, all the models produce very similar precipitation distributions. However, when water vapor is confined to relatively shallow layers, the ability of the sigma coordinate models to simulate the timing, location, and amount of precipitation is severely compromised.

  2. Stability of periodic steady-state solutions to a non-isentropic Euler-Maxwell system

    NASA Astrophysics Data System (ADS)

    Liu, Cunming; Peng, Yue-Jun

    2017-10-01

    This paper is concerned with a stability problem in a periodic domain for a non-isentropic Euler-Maxwell system without temperature diffusion term. This system is used to describe the dynamics of electrons in magnetized plasmas when the ion density is a given smooth function which can be large. When the initial data are close to the steady states of the system, we show the global existence of smooth solutions which converge toward the steady states as the time tends to infinity. We make a change of unknown variables and choose a non-diagonal symmetrizer of the full Euler equations to get the dissipation estimates. We also adopt an induction argument on the order of derivatives of solutions in energy estimates to get the stability result.

  3. The Cauchy problem for the pressureless Euler/isentropic Navier-Stokes equations

    NASA Astrophysics Data System (ADS)

    Choi, Young-Pil; Kwon, Bongsuk

    2016-07-01

    We present a new hydrodynamic model consisting of the pressureless Euler equations and the isentropic compressible Navier-Stokes equations where the coupling of two systems is through the drag force. This coupled system can be derived, in the hydrodynamic limit, from the particle-fluid equations that are frequently used to study the medical sprays, aerosols and sedimentation problems. For the proposed system, we first construct the local-in-time classical solutions in an appropriate L2 Sobolev space. We also establish the a priori large-time behavior estimate by constructing a Lyapunov functional measuring the fluctuation of momentum and mass from the averaged quantities, and using this together with the bootstrapping argument, we obtain the global classical solution. The large-time behavior estimate asserts that the velocity functions of the pressureless Euler and the compressible Navier-Stokes equations are aligned exponentially fast as time tends to infinity.

  4. Decay estimates of solutions to the bipolar non-isentropic compressible Euler–Maxwell system

    NASA Astrophysics Data System (ADS)

    Tan, Zhong; Wang, Yong; Tong, Leilei

    2017-10-01

    We consider the global existence and large time behavior of solutions near a constant equilibrium state to the bipolar non-isentropic compressible Euler–Maxwell system in {R}3 , where the background magnetic field could be non-zero. The global existence is established under the assumption that the H 3 norm of the initial data is small, but its higher order derivatives could be large. Combining the negative Sobolev (or Besov) estimates with the interpolation estimates, we prove the optimal time decay rates of the solution and its higher order spatial derivatives. In this sense, our results improve the similar ones in Wang et al (2012 SIAM J. Math. Anal. 44 3429–57).

  5. Isentropic Compression of Nitroplastized Estane to ≈ 35 KBAR on the Sandia Z-Machine

    NASA Astrophysics Data System (ADS)

    Gustavsen, R. L.; Dattelbaum, D. M.; Orler, E. B.; Hooks, D. E.; Alcon, R. R.; Sheffield, S. A.; Hall, C. E.; Baer, M. R.

    2006-07-01

    Nitroplasticized Estane (hereafter NP-Estane) is the plastic binder used to hold HMX grains together in the plastic bonded explosive PBX 9501. It is a mixture of 49 wt. % Estane®5703 (BF Goodrich), 49 wt. % Nitroplasticizer (a 50/50 eutectic mixture of bis(2,2-dinitropropyl)formal and bis(2,2 dinitropropyl)acetal), and 2 wt. % Irganox® 1010 stabilizer. NP-Estane samples 0.1 - 2 mm thick were prepared by compression molding at 110°C. Hydrostatic compression to 2 kbar was measured at 34, 43, and 53°C. CP was measured at ambient conditions. NP-Estane was also isentropically compressed to ≈ 35 kbar in experiment Z1251 on the Sandia Z-Machine. Profiles of ramp waves transmitted through NP-Estane were measured and compared with a free surface reference profile using Hayes's "Backward" analysis and repeated forward analysis with the CTH hydrocode. The following thermodynamic quantities have been obtained; volume coefficient of thermal expansion α = 7.2(10-4)/C, CP = 1.76 J/g C, CV = 1.41 J/g C, isentropic and isothermal bulk moduli, BS = 36.4 kbar, BT = 29.3 kbar, Grüneisen constant Γ = 1.45. The Z1251 experiment is well fit using a Mie-Grüneisen equation of state with the quadratic US - uP relation, US = 1.69 + 2.7uP - (0.7/1.69)uP2 km/s.

  6. On the relation of 6.7-micron water vapour features to isentropic distributions of potential vorticity

    NASA Technical Reports Server (NTRS)

    Manney, Gloria L.; Stanford, John L.

    1987-01-01

    Currently available isentropic maps of potential vorticity (IPV maps) are of low resolution. In this note, the possibility of using 6.7-micron satellite-derived water vapor measurements to obtain higher resolution information about IPV distributions is examined. While attempts to related the two data sets analytically have so far proved unsuccessful, a qualitative comparison shows very similar features in both. The results obtained here suggest that, over limited areas, it may be possible to use 6.7-micron brightness temperatures to obtain approximate contours for water vapor mixing ratio on a particular isentropic surface in the upper troposphere. For areas free of high clouds, these contours are expected to parallel the IPV contours on this surface. In a case study, the resulting map exhibits dramatically increased horizontal resolution compared with present IPV maps, detailing an intriguing upper-tropospheric feature at subsynoptic scales.

  7. Loading-path dependent deformation of nanocrystalline Ta under single- and double-shock, and quasi-isentropic compression

    NASA Astrophysics Data System (ADS)

    Tang, M. X.; E, J. C.; Wang, L.; Luo, S. N.

    2017-03-01

    We investigate dynamic deformation of nanocrystalline Ta under single- and double-shock, and quasi-isentropic compression, with large-scale molecular dynamics simulations. Orientation mapping, selected area electron diffraction, and x-ray diffraction are implemented for microstructure analysis. Different deformation modes are found for different loading paths, and are attributed to the differences in temperature rise induced by dynamic compression. For sufficiently strong shocks, catastrophic activation of slip systems and their growth in single-shock loading with the largest temperature rise lead to amorphization and recrystallization, while stacking faults and dislocation slip dominate deformation in double-shock loading with intermediate temperature rise, and deformation twinning is the principal mode in quasi-isentropic loading with the least temperature rise.

  8. Prediction of flow rates through an orifice at pressures corresponding to the transition between molecular and isentropic flow

    SciTech Connect

    DeMuth, S.F.; Watson, J.S.

    1985-01-01

    A model of compressible flow through an orifice, in the region of transition from free molecular to isentropic expansion flow, has been developed and tested for accuracy. The transitional or slip regime is defined as the conditions where molecular interactions are too many for free molecular flow modeling, yet not great enough for isentropic expansion flow modeling. Due to a lack of literature establishing a well-accepted model for predicting transitional flow, it was felt such work would be beneficial. The model is nonlinear and cannot be satisfactorily linearized for a linear regression analysis. Consequently, a computer routine was developed which minimized the sum of the squares of the residual flow for the nonlinear model. The results indicate an average accuracy within 15% of the measured flow throughout the range of test conditions. Furthermore, the results of the regression analysis indicate that the transitional regime lies between Knudsen numbers of approximately 2 and 45. 4 refs., 3 figs., 1 tab.

  9. Extended x-ray absorption fine structure measurements of quasi-isentropically compressed vanadium targets on the OMEGA laser

    SciTech Connect

    Yaakobi, B.; Boehly, T. R.; Sangster, T. C.; Meyerhofer, D. D.; Remington, B. A.; Allen, P. G.; Pollaine, S. M.; Lorenzana, H. E.; Lorenz, K. T.; Hawreliak, J. A.

    2008-06-15

    The use of in situ extended x-ray absorption fine structure (EXAFS) for characterizing nanosecond laser-shocked vanadium, titanium, and iron has recently been demonstrated. These measurements are extended to laser-driven, quasi-isentropic compression experiments (ICE). The radiation source (backlighter) for EXAFS in all of these experiments is obtained by imploding a spherical target on the OMEGA laser [T. R. Boehly et al., Rev. Sci. Instrum. 66, 508 (1995)]. Isentropic compression (where the entropy is kept constant) enables to reach high compressions at relatively low temperatures. The absorption spectra are used to determine the temperature and compression in a vanadium sample quasi-isentropically compressed to pressures of up to {approx}0.75 Mbar. The ability to measure the temperature and compression directly is unique to EXAFS. The drive pressure is calibrated by substituting aluminum for the vanadium and interferometrically measuring the velocity of the back target surface by the velocity interferometer system for any reflector (VISAR). The experimental results obtained by EXAFS and VISAR agree with each other and with the simulations of a hydrodynamic code. The role of a shield to protect the sample from impact heating is studied. It is shown that the shield produces an initial weak shock that is followed by a quasi-isentropic compression at a relatively low temperature. The role of radiation heating from the imploding target as well as from the laser-absorption region is studied. The results show that in laser-driven ICE, as compared with laser-driven shocks, comparable compressions can be achieved at lower temperatures. The EXAFS results show important details not seen in the VISAR results.

  10. CHARICE 1.0 : an IDL application for characteristics-based inverse analysis of isentropic compression experiments.

    SciTech Connect

    Davis, Jean-Paul

    2007-09-01

    CHARICE is a multi-platform computer application that analyzes velocity waveform data from ramp-wave experiments to determine a material's quasi-isentropic loading response in stress and density using an iterative characteristics-based approach. The application was built using ITT Visual Information Solutions Interactive Data Language (IDL{reg_sign}), and features graphical interfaces for all user interaction. This report describes the calculation method and available analysis options, and gives instructions for using the application.

  11. The lifespan of 3D radial solutions to the non-isentropic relativistic Euler equations

    NASA Astrophysics Data System (ADS)

    Wei, Changhua

    2017-10-01

    This paper investigates the lower bound of the lifespan of three-dimensional spherically symmetric solutions to the non-isentropic relativistic Euler equations, when the initial data are prescribed as a small perturbation with compact support to a constant state. Based on the structure of the hyperbolic system, we show the almost global existence of the smooth solutions to Eulerian flows (polytropic gases and generalized Chaplygin gases) with genuinely nonlinear characteristics. While for the Eulerian flows (Chaplygin gas and stiff matter) with mild linearly degenerate characteristics, we show the global existence of the radial solutions, moreover, for the non-strictly hyperbolic system (pressureless perfect fluid) satisfying the mild linearly degenerate condition, we prove the blowup phenomenon of the radial solutions and show that the lifespan of the solutions is of order O(ɛ ^{-1}), where ɛ denotes the width of the perturbation. This work can be seen as a complement of our work (Lei and Wei in Math Ann 367:1363-1401, 2017) for relativistic Chaplygin gas and can also be seen as a generalization of the classical Eulerian fluids (Godin in Arch Ration Mech Anal 177:497-511, 2005, J Math Pures Appl 87:91-117, 2007) to the relativistic Eulerian fluids.

  12. Development of quasi-isentropic drives to 500 GPa and beyond

    NASA Astrophysics Data System (ADS)

    Prisbrey, Shon; Park, Hye-Sook; Maddox, Brian; Remington, Bruce; Cavallo, Robert; May, Mark; Arsenlis, Tom

    2013-06-01

    The ability to reliably measure materials at energy densities exceeding 5 × 1011 J/m3 (500 GPa) requires an experimental platform that reaches such energy densities in a controlled manner and in a configuration that allows measurements to occur. We have developed a staged shock drive that will quasi-isentropically ramp materials such as Ta and Mo into such a high energy density state and simultaneously keep the materials substantially below their melting point, i.e., in their solid phase. Recent measurements of our platform on the National Ignition Facility have confirmed our ability to predict the resultant drive with a peak pressure of ~500 GPa. Separate experiments at the same facility have recently demonstrated that a drive with peak pressures >800 GPa is possible. We will show the experimental platform, the simulated and measured drives produced by the platform for ~500 GPa and ~800 GPa drive shots. We will also show an experimental platform which utilizes the drive and measurements of the samples to infer material strength. This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344. LLNL-ABS-620612.

  13. Computing Isentropic Flow Properties of Air/R-134a Mixtures

    NASA Technical Reports Server (NTRS)

    Kvaternik, Ray

    2006-01-01

    MACHRK is a computer program that calculates isentropic flow properties of mixtures of air and refrigerant R-134a (tetrafluoroethane), which are used in transonic aerodynamic testing in a wind tunnel at Langley Research Center. Given the total temperature, total pressure, static pressure, and mole fraction of R-134a in a mixture, MACHRK calculates the Mach number and the following associated flow properties: dynamic pressure, velocity, density, static temperature, speed of sound, viscosity, ratio of specific heats, Reynolds number, and Prandtl number. Real-gas effects are taken into account by treating the gases comprising the mixture as both thermally and calorically imperfect. The Redlich-Kwong equation of state for mixtures and the constant-pressure ideal heat-capacity equation for the mixture are used in combination with the departure- function approach of thermodynamics to obtain the equations for computing the flow properties. In addition to the aforementioned calculations for air/R-134a mixtures, a research version of MACHRK can perform the corresponding calculations for mixtures of air and R-12 (dichlorodifluoromethane) and for air/SF6 mixtures. [R-12 was replaced by R-134a because of environmental concerns. SF6 has been considered for use in increasing the Reynolds-number range.

  14. Mechanical response of metals under dynamic loading off the principal Hugoniot and isentrope

    NASA Astrophysics Data System (ADS)

    Seagle, Christopher

    2015-06-01

    Controlled dynamic loading of materials on phase-space paths off the principal Hugoniot and isentrope provide a stringent test of equation of state models in regions not typically experimentally constrained. Maturation of hardware design and pulse-shaping capabilities for shock-ramp experiments at Sandia's Z Machine have been exploited to test the mechanical response of a wide range of metals on ramp compression initiated from a well-defined Hugoniot state. A range of 1-8 km/s impact velocities are possible before initiating a ramp wave in a test sample. Capabilities and challenges of this type of experiment will be presented along with recent data on platinum, tin, cerium, and tantalum. Results of these experiments will be discussed in relation to existing equation of state data and models, and the future outlook for experimental constraints on material response on controlled off-principal loading paths. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  15. Isentropic Gas Flow for the Compressible Euler Equation in a Nozzle

    NASA Astrophysics Data System (ADS)

    Tsuge, Naoki

    2013-08-01

    We study the motion of isentropic gas in a nozzle. Nozzles are used to increase the thrust of engines or to accelerate a flow from subsonic to supersonic. Nozzles are essential parts for jet engines, rocket engines and supersonicwind tunnels. In the present paper, we consider unsteady flow, which is governed by the compressible Euler equation, and prove the existence of global solutions for the Cauchy problem. For this problem, the existence theorem has already been obtained for initial data away from the sonic state, (Liu in Commun Math Phys 68:141-172, 1979). Here, we are interested in the transonic flow, which is essential for engineering and physics. Although the transonic flow has recently been studied (Tsuge in J Math Kyoto Univ 46:457-524, 2006; Lu in Nonlinear Anal Real World Appl 12:2802-2810, 2011), these papers assume monotonicity of the cross section area. Here, we consider the transonic flow in a nozzle with a general cross section area. When we prove global existence, the most difficult point is obtaining a bounded estimate for approximate solutions. To overcome this, we employ a new invariant region that depends on the space variable. Moreover, we introduce a modified Godunov scheme. The corresponding approximate solutions consist of piecewise steady-state solutions of an auxiliary equation, which yield a desired bounded estimate. In order to prove their convergence, we use the compensated compactness framework.

  16. Effects of various assumptions on the calculated liquid fraction in isentropic saturated equilibrium expansions

    NASA Technical Reports Server (NTRS)

    Bursik, J. W.; Hall, R. M.

    1980-01-01

    The saturated equilibrium expansion approximation for two phase flow often involves ideal-gas and latent-heat assumptions to simplify the solution procedure. This approach is well documented by Wegener and Mack and works best at low pressures where deviations from ideal-gas behavior are small. A thermodynamic expression for liquid mass fraction that is decoupled from the equations of fluid mechanics is used to compare the effects of the various assumptions on nitrogen-gas saturated equilibrium expansion flow starting at 8.81 atm, 2.99 atm, and 0.45 atm, which are conditions representative of transonic cryogenic wind tunnels. For the highest pressure case, the entire set of ideal-gas and latent-heat assumptions are shown to be in error by 62 percent for the values of heat capacity and latent heat. An approximation of the exact, real-gas expression is also developed using a constant, two phase isentropic expansion coefficient which results in an error of only 2 percent for the high pressure case.

  17. Coupled ocean-atmosphere modeling on horizontally icosahedral and vertically hybrid-isentropic/isopycnic grids.

    NASA Astrophysics Data System (ADS)

    Bleck, Rainer; Sun, Shan; Li, Haiqin; Benjamin, Stan

    2016-04-01

    Current efforts to close the gap between weather prediction and climate models have led to the construction of a coupled ocean-atmosphere system consisting of two high-resolution component models, operating on matching icosahedral grids and utilizing adaptive, near-isentropic/isopycnic vertical coordinates. The two components models, FIM and HYCOM (the latter converted to an icosahedral mesh for this purpose), have been tested extensively in twice-daily global medium-range weather prediction (http://fim.noaa.gov) and in real-time ocean data assimilation (http://hycom.org), respectively. The use of matching horizontal grids, currently at resolutions of 15km, 30km and 60km, avoids coastline ambiguities and interpolation errors at the air-sea interface. The intended purpose of the coupled model being subseasonal-to-seasonal prediction, our focus is on mid-term precipitation biases and the statistical steadiness of the atmospheric circulation (blocking frequency, Rossby wave breaking, meridional heat transport, etc.), as well as on possible causes of ocean model drift. An attempt is made to isolate the weather model's role in modifying water mass properties and ocean circulations (including meridional overturning) by comparing coupled model results to ocean-only experiments forced by observed atmospheric boundary conditions. A multi-decadal run at 60km resolution is used to illustrate ENSO variability in the coupled system.

  18. A Survey of the Isentropic Euler Vortex Problem Using High-Order Methods

    NASA Technical Reports Server (NTRS)

    Spiegel, Seth C.; Huynh, H. T.; DeBonis, James R.

    2015-01-01

    The flux reconstruction (FR) method offers a simple, efficient, and easy to implement method, and it has been shown to equate to a differential approach to discontinuous Galerkin (DG) methods. The FR method is also accurate to an arbitrary order and the isentropic Euler vortex problem is used here to empirically verify this claim. This problem is widely used in computational fluid dynamics (CFD) to verify the accuracy of a given numerical method due to its simplicity and known exact solution at any given time. While verifying our FR solver, multiple obstacles emerged that prevented us from achieving the expected order of accuracy over short and long amounts of simulation time. It was found that these complications stemmed from a few overlooked details in the original problem definition combined with the FR and DG methods achieving high-accuracy with minimal dissipation. This paper is intended to consolidate the many versions of the vortex problem found in literature and to highlight some of the consequences if these overlooked details remain neglected.

  19. Isentropic Compression of Nitroplastized Estane to 40 KBAR on the Sandia Z-Machine

    NASA Astrophysics Data System (ADS)

    Gustavsen, Rick; Hall, Clint

    2005-07-01

    Nitroplasticized Estane is the plastic binder used to hold HMX grains together in the plastic bonded explosive PBX 9501. As part of an effort to characterize PBX 9501, we isentropically compressed the explosive and its constituents to ˜ 40 kbar on the Sandia Z-Machine. Nitroplasticized Estane binder samples were prepared as follows: A mixture of 49 wt. % Estane^5703 (BF Goodrich), 49 wt. % Nitroplasticizer (a 50/50 eutectic mixture of bis(2,2-dinitropropyl)formal and bis(2,2 dinitropropyl)acetal), and 2 wt. % Irganox^ 1010 stabilizer was prepared as for PBX 9501 binder. Samples were compression molded into 0.1 -- 2 mm thick films at 110^oC. These were then mounted between 6061 Aluminum Z panels and PMMA or LiF VISAR widows. PMMA washers between the panel and window stabilized the binder thickness. Profiles of ramp waves transmitted through several sample thicknesses were measured and compared with a reference profile. A simple analysis of the results indicates that the binder behavior can be described using the Universal Liquid Hugoniot with an ambient sound speed of 1.7 km/s.

  20. Disposition of transuranic residues from plutonium isentropic compression experiment (Pu-ICE) constucted at Z machine

    SciTech Connect

    Goyal, Kapil K; French, David M; Humphrey, Betty J; Gluth, Jeffry

    2010-01-01

    In 1992, the U.S. Congress passed legislation to discontinue above- and below-ground testing of nuclear weapons. Because of this, the U.S. Department of Energy (DOE) must rely on laboratory experiments and computer-based calculations to verify the reliability of the nuclear stockpile. The Sandia National Laboratories/New Mexico (SNL/NM) Z machine was developed to support the science-based approach for mimicking nuclear explosions and stockpile stewardship. Plutonium (Pu) isotopes with greater than ninety-eight percent enrichment were used in the experiments. In May 2006, SNL/NM received authority that the Z Machine Isentropic Compression Experiments could commence. Los Alamos National Laboratory (LANL) provided the plutonium targets and loaded the target assemblies provided by SNL/NM. Three experiments were conducted from May through July 2006. The residues from each experiment, which weighed up to 913 pounds, were metallic and were packaged into a 55-gallon drum each. SNL/NM conducts the experiments and provides temporary storage for the drums until shipment to LANL for final waste certification for disposal at the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico. This paper presents a comprehensive approach for documenting generator knowledge for characterization of waste in cooperation with scientists at the two laboratories and addresses a variety of essential topics.

  1. An isentropic perspective of the atmospheric overturning induced by Hector the Convector

    NASA Astrophysics Data System (ADS)

    Dauhut, Thibaut; Chaboureau, Jean-Pierre; Mascart, Patrick; Pauluis, Olivier

    2017-04-01

    The overturning inside Hector the Convector, a tropical multicellular convective system of the Northern Australia that regularly overshoots into the stratosphere, is synthesized at the scale of a Large-Eddy Simulation (Dauhut et al., 2015). The isentropic analysis offers the advantage to filter out the reversible motions due to the gravity waves and to take into account the turbulent fluxes that contribute to the vertical transport. Two key circulations are evidenced: the troposphere-deep overturning and the mass exchange due to the overshoots into the stratosphere. The transition from deep to very deep convection is associated with a change in the diabatic tendency inside the tallest updrafts: the latent heat release due to the freezing of a large amount of hydrometeors overrode the loss of energy due to mixing with the drier, colder air of the environment. In agreement with a previous study of Hector examining the properties of its two tallest updrafts (Dauhut et al., 2016), the entrainment rate exhibits a minimum during the very deep convection phase, as low as 0.04 /km. The two-stream approximation corroborates the Eulerian computation of the vertical mass flux in the mid-troposphere and in the lower stratosphere. It however gives a lower estimate of the flux in the upper troposphere, filtering out the reversible motions, and a larger estimate in the lower troposphere and at the tropopause, where slow vertical motions contribute significantly to the transport.

  2. The response of ceramic powders to high-level quasi-isentropic dynamic loads.

    SciTech Connect

    Lawrence, Raymond Jeffery Jr.; Grady, Dennis Edward; Hall, Charles Ainsley

    2003-07-01

    The pulsed-power Z machine, in an isentropic compression experiment (ICE) mode, will allow the dynamic characterization of porous materials - here various ceramic powders, e.g., Al{sub 2}O{sub 3}, WC, ZrO{sub 2} - at roughly half their solid densities. A cylindrical configuration can provide megabar-level loads on an annulus of the sample material. Data will be provided by velocity interferometers that measure free-surface (or possibly interface) particle velocities. Differing sample thicknesses using stepped or conical geometries yield experimental efficiency by allowing multiple data records on single shots. With the p/{alpha} model for porous materials, the one-dimensional Lagrangian hydrocode WONDY provides the needed analyses. Based on static data, both power-law and quadratic crush curves are employed. Within the model constraints, we suggest that the most important parameter for characterizing the material is the crush strength, p{sub s}. With adequate sample thicknesses, the planned velocity measurements differentiate among the various assumptions for p{sub s}.

  3. The Response of Ceramic Powders to High-Level Quasi-Isentropic Dynamic Loads

    NASA Astrophysics Data System (ADS)

    Lawrence, R. J.; Grady, D. E.; Hall, C. A.

    2004-07-01

    The pulsed-power Z machine, in an isentropic compression experiment (ICE) mode, will allow the dynamic characterization of porous materials—here various ceramic powders, e.g., Al2O3, WC, ZrO2—at roughly half their solid densities. A cylindrical configuration can provide megabar-level loads on an annulus of the sample material. Data will be provided by velocity interferometers that measure free-surface (or possibly interface) particle velocities. Differing sample thicknesses using stepped or conical geometries yield experimental efficiency by allowing multiple data records on single shots. With the p/α model for porous materials, the one-dimensional Lagrangian hydrocode WONDY provides the needed analyses. Based on static data, both power-law and quadratic crush curves are employed. Within the model constraints, we suggest that the most important parameter for characterizing the material is the crush strength, ps. With adequate sample thicknesses, the planned velocity measurements differentiate among the various assumptions for ps.

  4. An unusual stratospheric ozone decrease linked to isentropic air-mass transport as observed over Irene (25.5° S, 28.1° E) in mid-May 2002

    NASA Astrophysics Data System (ADS)

    Semane, N.; Bencherif, H.; Morel, B.; Hauchecorne, A.; Diab, R. D.

    2005-12-01

    A prominent ozone minimum of less than 240 Dobson Units (DU) was observed over Irene (25.5° S, 28.1° E) by the Total Ozone Mapping Spectrometer (TOMS) during May 2002 with extremely low ozone value of less than 219 DU recorded on 12 May, as compared to a climatological mean of 249 DU for May between 1999 and 2005. In this study, the vertical structure of this ozone minimum is examined using ozonesonde measurements performed over Irene on 15 May 2002, when the total ozone (as given by TOMS) was about 226 DU. Indeed, it is found that the ozone minimum is of Antarctic polar origin with a low-ozone layer in the middle stratosphere above 625 K and of tropical origin with low-ozone layer between 400-K and 450-K isentropic levels in the lower stratosphere. The upper and lower depleted parts of the ozonesonde profile for 15 May, are respectively attributed to equatorward and poleward transport of low-ozone air toward the subtropics. The tropical air moving over Irene and the polar one passing over the same area associated with enhanced planetary-wave activity are simulated successfully using a high-resolution advection contour model (MIMOSA) of Potential Vorticity. Indeed, in mid-May 2002, MIMOSA maps show a polar vortex filament in the middle stratosphere above the 625-K isentropic level and they show also tropical air-masses moving southward (over Irene) in the lower stratosphere between 400-K and 450-K isentropic levels. The winter stratospheric wave driving and its associated localized isentropic mixing leading to the ozone minimum are investigated by means of two diagnostic tools: the Eliassen-Palm flux and the effective diffusivity computed from the European Center for Medium-range Weather Forecasts (ECMWF) fields. The unusual distribution of ozone over Irene during May 2002 in the middle stratosphere is closely connected to the anomalously pre-conditioned structure of the polar vortex at that time of the year. Indeed, the perturbed vortex was typically predisposed

  5. Sound Speed of Liquid Iron Along the Outer Core Isentrope: New Pre-heated Ramp Compression Experiments

    NASA Astrophysics Data System (ADS)

    Asimow, P. D.; Nguyen, J.; Akin, M. C.; Fatýanov, O. V.

    2015-12-01

    Detailed elasticity data on liquid Fe and candidate molten core alloys should offer new constraints on the under-constrained problem of Earth's core composition. Density, sound speed, and the gradient in sound speed with pressure are each potentially distinct experimental constraints and are each well-known for Earth. The gradient in sound speed, though, has not been used because sound speed depends on both T and P, such that data must be collected or reconstructed along the correct, nearly adiabatic, thermal profile. Reconstruction requires the Grüneisen γ, which is composition-dependent, and data over a large P-T space to allow extrapolation. Both static and dynamic compression methods could be used, but the conditions (140 - 330 GPa and 4000 - 6000 K) are very challenging for static methods and standard shock compression only samples the outer core P-T profile at a single P. Instead we are applying quasi-isentropic dynamic ramp compression, using pre-heating of the target and impedance of the leading edge of a graded-density impactor (GDI) to select a probable outer core isentrope. The target material is melted and raised to a point on the outer core isentrope by the initial shock, then quasi-isentropically ramped to a maximum P by increasing shock impedance of trailing GDI layers. Particle velocity is monitored by photonic doppler velocimetry (PDV) at two step thicknesses at the interface of Fe or Fe-alloy target and MgO windows. The difference in arrival time of each particle velocity at the two steps directly gives the Lagrangian sound speed vs. particle velocity, which is integrated to obtain Pand density. At the writing of this abstract, we have completed one shot of this type. We successfully heated a two-step Fe target in a Mo capsule with MgO windows to 1350 °C, maintaining sufficient alignment and reflectivity to collect PDV signal returns. We characterized the velocity correction factor for PDV observation through MgO windows, and have confirmed

  6. Global classical solutions to the 3D isentropic compressible Navier-Stokes equations in a bounded domain

    NASA Astrophysics Data System (ADS)

    Yu, Haibo; Zhao, Junning

    2017-01-01

    In this paper, we study the global existence for classical solutions to the 3D isentropic compressible Navier-Stokes equations in a cuboid domain. Compared to the Cauchy problem studied in Hoff (1995 J. Differ. Equ. 120 215-54), Hoff (2005 J. Math. Fluid Mech. 7 315-38), Huang et al (2012 Commun. Pure Appl. Math. 65 549-85), some new thoughts are applied to obtain upper bounds for density. Precisely, through piecewise estimation and some time-depending a priori estimates, we establish time-uniform upper bounds for density under the assumption that the initial energy is small. The initial vacuum is allowed.

  7. Isentropic calculation for thermodynamic properties of polarized liquid 3He by considering the effect of spin-dependent correlation function

    NASA Astrophysics Data System (ADS)

    Bordbar, G. H.; Hosseini, S.; Poostforush, A.

    2017-05-01

    Correlations in quantum fluids such as liquid 3He continue to be of high interest to scientists. Based on this prospect, the present work is devoted to study the effects of spin-spin correlation function on the thermodynamic properties of polarized liquid 3He such as pressure, velocity of sound, adiabatic index and adiabatic compressibility along different isentropic paths, using the Lennard-Jones potential and employing the variational approach based on cluster expansion of the energy functional. The inclusion of this correlation improves our previous calculations and leads to good agreements with experimental results.

  8. Interannual variability of the 4-day wave and isentropic mixing inside the polar vortex in midwinter of the Southern Hemisphere upper stratosphere

    NASA Astrophysics Data System (ADS)

    Mizuta, Ryo; Yoden, Shigeo

    2002-12-01

    Interannual variations of the flow field and large-scale horizontal transport and mixing inside the wintertime polar vortex of the Southern Hemisphere upper stratosphere are investigated using isentropic winds obtained from the U.K. Met Office assimilated data for nine years of 1992-2000. We focused on the midwinter, July, when the polar vortex is not much distorted, although an eastward propagating wave called the 4-day wave is observed in some years in the polar region. Finite-time Lyapunov exponents are computed, and contour advections are done to examine stirring and mixing in the polar region. When the 4-day wave has a large amplitude, effective mixing through a stretching and folding process is seen inside the polar vortex. Finite-time Lyapunov exponents are sometimes as large as the midlatitudes, and the material contours of small areas grow exponentially in time on the poleward side of 70°S. Such mixing properties are not uniform inside the vortex. When the wave is not clearly seen, on the other hand, wind fields are close to a solid body rotation around the pole, and mixing is very small; Lyapunov exponents are small, and the material contours grow linearly in time by the stretching due to the meridional shear of the polar night jet. Such interannual variability of the strength of the mixing is correlated with the variability of the perturbation amplitude of potential vorticity in the polar region.

  9. Disposition of transuranic residues from plutonium isentropic compression experiment (Pu-ice) conducted at Z machine

    SciTech Connect

    Goyal, Kapil K; French, David M; Humphrey, Betty J; Gluth, Jeffry

    2010-01-01

    In 1992, the U.S. Congress passed legislation to discontinue above- and below-ground testing of nuclear weapons. Because of this, the U.S. Department of Energy (DOE) must rely on laboratory experiments and computer-based calculations to verify the reliability of the nation's nuclear stockpile. The Sandia National Laboratories/New Mexico (SNL/NM) Z machine was developed by the DOE to support its science-based approach to stockpile stewardship. SNL/NM researchers also use the Z machine to test radiation effects on various materials in experiments designed to mimic nuclear explosions. Numerous components, parts, and materials have been tested. These experiments use a variety of radionuclides; however, plutonium (Pu) isotopes with greater than ninety-eight percent enrichment are the primary radionuclides used in the experiments designed for stockpile stewardship. In May 2006, SNL/NM received authority that the Z Machine Isentropic Compression Experiments could commence. Los Alamos National Laboratory (LANL) provided the plutonium targets and loaded the target assemblies, which were fabricated by SNL/NM. LANL shipped the loaded assemblies to SNL/NM for Z machine experiments. Three experiments were conducted from May through July 2006. The residues from each experiment, which weighed up to 913 pounds, were metallic and packaged into a respective 55-gallon drum each. Based on a memorandum of understanding between the two laboratories, LANL provides the plutonium samples and the respective radio-isotopic information. SNL/NM conducts the experiments and provides temporary storage for the drums until shipment to LANL for final waste certification for disposal at the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico. This paper presents a comprehensive approach for documenting generator knowledge for characterization of waste in cooperation with scientists at the two laboratories and addresses a variety of topics such as material control and accountability

  10. A Hamiltonian Particle-Mesh Method for Hydrostatic Flow in Isentropic Coordinates

    NASA Astrophysics Data System (ADS)

    Peeters, Bob; Bokhove, Onne; Frank, Jason

    2010-05-01

    Although our climate is ultimately driven by (nonuniform) solar heating, many aspects of the flow can be understood qualitatively from forcing-free and frictionless dynamics. In the limit of zero forcing and dissipation, our weather system falls under the realm of Hamiltonian fluid dynamics and the flow conserves potential vorticity (PV), energy and phase-space structure. We think that discrete conservation of phase-space structure is essential for reproducing the correct statistics in climate forecasts. To find a Hamiltonian discretization, we start from the Lagrangian momentum equations with entropy as vertical label coordinate. Entropy is conserved on fluid parcels in adiabatic flow. New is that we view the potential as an Eulerian function. It means that the Lagrangian equation for mass conservation is replaced by an integral relation over all fluid parcels, recovering the Eulerian density field. This is the so-called parcel formulation [1]. The spatial discretization consists of two steps: 1) a finite element (FEM) discretization in the entropic direction, and 2) a discretization of horizontal Lagrangian label space. It leads to a discrete Poisson bracket constituting a Hamiltonian set of ODE's for a collection of discrete fluid particles moving on isentropic surfaces. The resulting Hamiltonian Particle-Mesh method, akin to [3], conserves mass, PV, energy and phase-space structure. A symplectic time integrator is used for our Hamiltonian system. The resulting fully discrete system allows backward error analysis for the energy. It is conserved without any drift in energy. We will prove the energy conservation, and show a systematic derivation of the Eulerian FEM Poisson bracket, following [2]. REFERENCES [1] O. Bokhove and M. Oliver, Parcel Eulerian-Lagrangian fluid dynamics for rotating geophysical flows, Proc. Roy. Soc. A. 462, pp. 2563-2573 (2006) [2] O. Bokhove and M. Oliver, Hamiltonian N layer model for atmospheric dynamics, Geophys. Astrophys. Fluid Dyn

  11. Isentropic mass exchange between the Tropics and extratropics in the stratosphere

    NASA Technical Reports Server (NTRS)

    Chen, Ping; Holton, James R.; O'Neill, Alan; Swinbank, Richard

    1994-01-01

    The isentropic mass exchange between the Tropics and extratropics in the stratosphere is investigated with a semi-Lagrangian transport model for the periods from 1 June to 31 October 1992 and from 1 December 1992 to 30 April 1993 using winds from the U.K. Meteorological Office data assimilation system. Calculations with an idealized, initially zonally symmetric tracer show that in the middle and upper stratosphere the bulk of tropical air is transported into the midlatitudes of the winter hemisphere although there exist quasi-permeable barriers in the subtropics. The transport takes place in the form of planetary-scale 'tongues' of material that are drawn poleward in association with the episodic amplification of planetary-scale waves in high latitudes of the winter hemisphere. Once air of tropical origin is transported to the midlatitudes it is irreversibly mixed with the midlatitude air in the 'surf zone.' Air of tropical origin can, however, hardly penetrate into the interior of the winter polar vortex until the breakdown of the vortex. Transport of tropical air into the midlatitudes of the summer hemisphere is strongly inhibited. In the lower stratosphere, tropical air is transported into the northern and southern midlatitudes. During the period from 1 June to 31 October 1992, the amount of tropical air transported into the Northern Hemisphere is, however, much smaller than that transported into the Southern Hemisphere, and there exist strong gradients in the tracer field in the equatorial region, indicating that there is a quasi-permeable barrier to cross-equator mass exchange. During the period from 1 December 1992 to 30 April 1993, on the other hand, roughly the same amounts of tropical air are transported into the Southern Hemisphere, and there exist strong gradients in the tracer field in the equatorial region, indicating that there is a quasi-permeable barrier to cross-equator mass exchange. During the period from 1 December 1992 to 30 April 1993, on the

  12. The compact capacitor bank CQ-1.5 employed in magnetically driven isentropic compression and high velocity flyer plate experiments.

    PubMed

    Wang, Guiji; Sun, Chengwei; Tan, Fuli; Zhao, Jianheng; Zhang, Ning; Liu, Cangli; Mo, Jianjun; Wang, Ganghua; Wang, Xiaosong

    2008-05-01

    Based on the low inductance capacitor, the parallel-plate transmission line, and the explosive network closing switch, a compact pulsed power generator CQ-1.5 has been developed at the Institute of Fluid Physics and is capable to deliver a current of peak of 1.5 MA within rise time of 500-570 ns into a 2-3 nH inductive load. The work is motivated to do isentropic compression experiments (ICEs) on metals up to 30-50 GPa and to launch flyer plates at velocities over 8 kms. The experiments were conducted with the diagnostics of both Doppler pin system and velocity interferometer system for any reflectors, and the measured free surface velocity histories of ICE samples were treated with a backward integration code. The results show that the isentropes of Cu and Al samples under 35 GPa are close to their Hugoniots within a deviation of 3%. The LY12 aluminum flyer plates were accelerated to a velocity over 8.96 kms.

  13. Modeling and Analysis of Global and Regional Climate Change in Relation to Atmospheric Hydrologic Processes

    NASA Technical Reports Server (NTRS)

    Johnson, Donald R.

    1998-01-01

    The goal of this research is the continued development and application of global isentropic modeling and analysis capabilities to describe hydrologic processes and energy exchange in the climate system, and discern regional climate change. This work involves a combination of modeling and analysis efforts involving 4DDA datasets and simulations from the University of Wisconsin (UW) hybrid isentropic-sigma (theta-sigma) coordinate model and the GEOS GCM.

  14. Modeling and Analysis of Global and Regional Climate Change in Relation to Atmospheric Hydrologic Processes

    NASA Technical Reports Server (NTRS)

    Johnson, Donald R.

    1998-01-01

    The goal of this research is the continued development and application of global isentropic modeling and analysis capabilities to describe hydrologic processes and energy exchange in the climate system, and discern regional climate change. This work involves a combination of modeling and analysis efforts involving 4DDA datasets and simulations from the University of Wisconsin (UW) hybrid isentropic-sigma (theta-sigma) coordinate model and the GEOS GCM.

  15. Measurement of quasi-isentropic compressibility of helium and deuterium at pressures of 1500-2000 GPa

    SciTech Connect

    Mochalov, M. A. Il'kaev, R. I.; Fortov, V. E.; Mikhailov, A. L.; Makarov, Yu. M.; Arinin, V. A.; Blikov, A. O.; Baurin, A. Yu.; Komrakov, V. A.; Ogorodnikov, V. A.; Ryzhkov, A. V.; Pronin, E. A.; Yukhimchuk, A. A.

    2012-10-15

    The quasi-isentropic compressibility of helium and deuterium plasmas at pressures of up to 1500-2000 GPa has been measured using devices with spherical geometry and an X-ray diagnostic complex comprising three betatrons and a multichannel imaging system with electro-optic gamma detectors. A deuterium density of 4.5 g/cm{sup 3} and a helium density of 3.8 g/cm{sup 3} have been obtained at pressures of 2210 and 1580 GPa, respectively. The internal energy of a deuterium plasma at the indicated pressure is about 1 MJ/cm{sup 3}, which is about 100 times greater than the specific energy of condensed chemical explosives. Analysis of the obtained data shows that the degree of helium ionization under the achieved plasma compression parameters is about 0.9.

  16. Thermodynamic properties of gaseous fluorocarbons and isentropic equilibrium expansions of two binary mixtures of fluorocarbons and argon

    NASA Technical Reports Server (NTRS)

    Talcott, N. A., Jr.

    1977-01-01

    Equations and computer code are given for the thermodynamic properties of gaseous fluorocarbons in chemical equilibrium. In addition, isentropic equilibrium expansions of two binary mixtures of fluorocarbons and argon are included. The computer code calculates the equilibrium thermodynamic properties and, in some cases, the transport properties for the following fluorocarbons: CCl2F, CCl2F2, CBrF3, CF4, CHCl2F, CHF3, CCL2F-CCl2F, CCLF2-CClF2, CF3-CF3, and C4F8. Equilibrium thermodynamic properties are tabulated for six of the fluorocarbons(CCl3F, CCL2F2, CBrF3, CF4, CF3-CF3, and C4F8) and pressure-enthalpy diagrams are presented for CBrF3.

  17. Influence of Sub-grid-Scale Isentropic Transports on McRAS Evaluations using ARM-CART SCM Datasets

    NASA Technical Reports Server (NTRS)

    Sud, Y. C.; Walker, G. K.; Tao, W. K.

    2004-01-01

    In GCM-physics evaluations with the currently available ARM-CART SCM datasets, McRAS produced very similar character of near surface errors of simulated temperature and humidity containing typically warm and moist biases near the surface and cold and dry biases aloft. We argued it must have a common cause presumably rooted in the model physics. Lack of vertical adjustment of horizontal transport was thought to be a plausible source. Clearly, debarring such a freedom would force the incoming air to diffuse into the grid-cell which would naturally bias the surface air to become warm and moist while the upper air becomes cold and dry, a characteristic feature of McRAS biases. Since, the errors were significantly larger in the two winter cases that contain potentially more intense episodes of cold and warm advective transports, it further reaffirmed our argument and provided additional motivation to introduce the corrections. When the horizontal advective transports were suitably modified to allow rising and/or sinking following isentropic pathways of subgrid scale motions, the outcome was to cool and dry (or warm and moisten) the lower (or upper) levels. Ever, crude approximations invoking such a correction reduced the temperature and humidity biases considerably. The tests were performed on all the available ARM-CART SCM cases with consistent outcome. With the isentropic corrections implemented through two different numerical approximations, virtually similar benefits were derived further confirming the robustness of our inferences. These results suggest the need for insentropic advective transport adjustment in a GCM due to subgrid scale motions.

  18. Influence of Sub-grid-Scale Isentropic Transports on McRAS Evaluations using ARM-CART SCM Datasets

    NASA Technical Reports Server (NTRS)

    Sud, Y. C.; Walker, G. K.; Tao, W. K.

    2004-01-01

    In GCM-physics evaluations with the currently available ARM-CART SCM datasets, McRAS produced very similar character of near surface errors of simulated temperature and humidity containing typically warm and moist biases near the surface and cold and dry biases aloft. We argued it must have a common cause presumably rooted in the model physics. Lack of vertical adjustment of horizontal transport was thought to be a plausible source. Clearly, debarring such a freedom would force the incoming air to diffuse into the grid-cell which would naturally bias the surface air to become warm and moist while the upper air becomes cold and dry, a characteristic feature of McRAS biases. Since, the errors were significantly larger in the two winter cases that contain potentially more intense episodes of cold and warm advective transports, it further reaffirmed our argument and provided additional motivation to introduce the corrections. When the horizontal advective transports were suitably modified to allow rising and/or sinking following isentropic pathways of subgrid scale motions, the outcome was to cool and dry (or warm and moisten) the lower (or upper) levels. Ever, crude approximations invoking such a correction reduced the temperature and humidity biases considerably. The tests were performed on all the available ARM-CART SCM cases with consistent outcome. With the isentropic corrections implemented through two different numerical approximations, virtually similar benefits were derived further confirming the robustness of our inferences. These results suggest the need for insentropic advective transport adjustment in a GCM due to subgrid scale motions.

  19. Dynamic Strength Analysis of Tantalum using a Multimode Rippled Target under Laser Driven Quasi-Isentropic Compression

    NASA Astrophysics Data System (ADS)

    Qian, Ping; Cavallo, Robert; Park, Hye-Sook; Plechaty, Chris; Prisbrey, Shon; Wilson, Mike; Maddox, Brian; Blobaum, Kerri; May, Robert

    2012-10-01

    We present results from a material strength analysis of tantalum using a multimode rippled target under quasi-isentropic plasma loading at pressure greater than 100GPa and strain rate above 106 s-1. The results are compared with test data measured at Omega Laser. A conventional approach [1,2] utilizes the RTI (Rayleigh-Taylor Instability) mechanism to infer material strength from the growth of a single sinusoidal mode pre-imposed on a target. This method was proven reliable [2,3], but there is room for improvement in efficiency. By deploying an initial perturbation with two or more sinusoidal modes superimposed onto a single target, we are able to collect more test data in a single experiment. Presented in this paper are the verification of a multimode approach against single mode; mode coupling development during the loading sequence; the behavior of induced modes; and the detection of those modes in both simulation and test measurements.[4pt] [1] B.A. Remington et at., Material Science and Technology, Vol. 22, No. 4, 2006[0pt] [2] H.S. Park et al., PRL. 104, 135504 (2010)[0pt] [3] N. R. Barton et al., J. of Applied Physics, 109, 073501, 2011

  20. A comparison of regional isentropic-sigma and sigma model simulations of the January 1979 Chicago blizzard

    NASA Technical Reports Server (NTRS)

    Zapotocny, Tom H.; Johnson, Donald R.; Reames, Fred M.

    1993-01-01

    In an initial effort in regional numerical weather prediction, results from the University of Wisconsin isentropic-sigma (UW theta-sigma) hybrid model and an 'identical' sigma model are compared. The two main objectives are to demonstrate the capability of the UW theta-sigma model for regional numerical weather prediction and to identify advantages of the hybrid model in simulating atmospheric water vapor transport and precipitation relative to the sigma model. The 72-h simulations produced by the two models extend over a region covering the western Pacific Ocean, North America, and the western Atlantic Ocean. The simulations begin at 0000 UTC 13 January 1979, a period during which an intense Chicago blizzard develops over the central United States. This period also includes the rapid development of a cyclone in the western Pacific Ocean. Results using the Global Weather Experiment (GWE) ECMWF level IIIB data as initial and verification data indicate that both models produce reasonable and similar 72-h simulations, with the UW theta-sigma model mass and momentum distributions being slightly more accurate than the sigma model. Of particular importance for the Chicago blizzard is that the UW theta-sigma model more accurately simulates water vapor transport northward from the Gulf of Mexico and westward from the Atlantic Ocean. As a result, the hybrid model more accurately simulates observed precipitation, especially over the northeastern U.S. and southeastern Canada.

  1. Global Resolution of the Physical Vacuum Singularity for Three-Dimensional Isentropic Inviscid Flows with Damping in Spherically Symmetric Motions

    NASA Astrophysics Data System (ADS)

    Zeng, Huihui

    2017-10-01

    For the gas-vacuum interface problem with physical singularity and the sound speed being {C^{{1}/{2}}}-Hölder continuous near vacuum boundaries of the isentropic compressible Euler equations with damping, the global existence of smooth solutions and the convergence to Barenblatt self-similar solutions of the corresponding porous media equation are proved in this paper for spherically symmetric motions in three dimensions; this is done by overcoming the analytical difficulties caused by the coordinate's singularity near the center of symmetry, and the physical vacuum singularity to which standard methods of symmetric hyperbolic systems do not apply. Various weights are identified to resolve the singularity near the vacuum boundary and the center of symmetry globally in time. The results obtained here contribute to the theory of global solutions to vacuum boundary problems of compressible inviscid fluids, for which the currently available results are mainly for the local-in-time well-posedness theory, and also to the theory of global smooth solutions of dissipative hyperbolic systems which fail to be strictly hyperbolic.

  2. A comparison of regional isentropic-sigma and sigma model simulations of the January 1979 Chicago blizzard

    NASA Technical Reports Server (NTRS)

    Zapotocny, Tom H.; Johnson, Donald R.; Reames, Fred M.

    1993-01-01

    In an initial effort in regional numerical weather prediction, results from the University of Wisconsin isentropic-sigma (UW theta-sigma) hybrid model and an 'identical' sigma model are compared. The two main objectives are to demonstrate the capability of the UW theta-sigma model for regional numerical weather prediction and to identify advantages of the hybrid model in simulating atmospheric water vapor transport and precipitation relative to the sigma model. The 72-h simulations produced by the two models extend over a region covering the western Pacific Ocean, North America, and the western Atlantic Ocean. The simulations begin at 0000 UTC 13 January 1979, a period during which an intense Chicago blizzard develops over the central United States. This period also includes the rapid development of a cyclone in the western Pacific Ocean. Results using the Global Weather Experiment (GWE) ECMWF level IIIB data as initial and verification data indicate that both models produce reasonable and similar 72-h simulations, with the UW theta-sigma model mass and momentum distributions being slightly more accurate than the sigma model. Of particular importance for the Chicago blizzard is that the UW theta-sigma model more accurately simulates water vapor transport northward from the Gulf of Mexico and westward from the Atlantic Ocean. As a result, the hybrid model more accurately simulates observed precipitation, especially over the northeastern U.S. and southeastern Canada.

  3. Technical Review Report for the Application for Contents Amendment for Shipping Isentropic Compression Experiment (ICE) Apparatus in 9977 Packaging

    SciTech Connect

    West, M

    2009-04-16

    This report documents the review of Application for Contents Amendment for Shipping Isentropic Compression Experiment (ICE) Apparatus in 9977 Packaging, prepared by Savannah River Packaging Technology (SRPT) of Savannah River National Laboratory (SRNL) of Savannah River Nuclear Solutions, LLC, -- the Submittal -- at the request of the Department of Energy's (DOE) National Nuclear Security Agency's (NNSA) Albuquerque Facility Operations Division, for the shipment of the ICE apparatus from Los Alamos National Laboratory (LANL), to Sandia National Laboratory (SNL). The ICE apparatus consists of a stainless steel assembly containing about 8 grams of {sup 239}Pu or its dose equivalent as noted in Table 1, Comparison of 9977 Content C.1 and the ICE Radioactive Contents, of the Submittal. The ICE target is mounted on the transport container assembly base. A Viton{sup R} O-ring seals the transport container base to the transport container body. Another Viton{sup R} O-ring seals the transport container handle to the transport container body. The ICE apparatus weighs less than 30 pounds and has less than 0.6 watts decay heat rate. For the Model 9977 Package, the maximum payload weight is 100 pounds and the maximum decay heat rate is 19 watts. Thus, the maximum payload weight and the maximum decay heat rate for the Model 9977 Package easily bound those for the ICE apparatus. This Addendum supplements the Safety Analysis Report for Packaging (SARP), Revision 2, for the Model 9977 Package and Addendum 1, Revision 2, to Revision 2 of the Model 9977 Package SARP. The ICE apparatus is considered as part of Content Envelope C.6, Samples and Sources, under the submittal for the Model 9978 Package SARP currently under review. The Staff at Lawrence Livermore National Laboratory (LLNL) recommends that the Submittal be approved by the DOE-Headquarters Certifying Official (EM-60), and incorporated into a subsequent revision to the current Certificate of Compliance (CoC), to the Model

  4. THERMAL ESCAPE IN THE HYDRODYNAMIC REGIME: RECONSIDERATION OF PARKER's ISENTROPIC THEORY BASED ON RESULTS OF KINETIC SIMULATIONS

    SciTech Connect

    Volkov, Alexey N.; Johnson, Robert E.

    2013-03-10

    The one-dimensional steady-state problem of thermal escape from a single-component atmosphere of mon- and diatomic gases is studied in the hydrodynamic (blow-off) regime using the direct simulation Monte Carlo method for an evaporative-type condition at the lower boundary. The simulations are performed for various depths into an atmosphere, indicated by a Knudsen number, Kn{sub 0}, equal to the ratio of the mean free path of molecules to the radial position of the source surface, ranging from 10 to 10{sup -5}, and for the range of the source Jeans parameter, {lambda}{sub 0}, equal to the ratio of gravitational and thermal energies, specific to blow-off. The results of kinetic simulations are compared with the isentropic model (IM) and the Navier-Stokes model. It is shown that the IM can be simplified if formulated in terms of the local Mach number and Jeans parameter. The simulations predict that at Kn{sub 0} < {approx} 10{sup -3} the flow includes a near-surface non-equilibrium Knudsen layer, a zone where the flow can be well approximated by the IM, and a rarefied far field. The corresponding IM solutions, however, only approach Parker's critical solution as {lambda}{sub 0} approaches the upper limit for blow-off. The IM alone is not capable for predicting the flow and requires boundary conditions at the top of the Knudsen layer. For small Kn{sub 0}, the scaled escape rate and energy loss rate are found to be independent of {lambda}{sub 0}. The simulation results can be scaled to any single-component atmosphere exhibiting blow-off if the external heating above the lower boundary is negligible, in particular, to sublimation-driven atmospheres of Kuiper belt objects.

  5. Constructing Synoptic Maps of Stratospheric Column Ozone from HALOE, SAGE and Balloonsonde Data Using Potential Vorticity Isentropic Coordinate Transformations

    NASA Technical Reports Server (NTRS)

    Hollandsworth, Stacey M.; Schoeberl, Mark R.; Morris, Gary A.; Long, Craig; Zhou, Shuntai; Miller, Alvin J.

    1999-01-01

    In this study we utilize potential vorticity - isentropic (PVI) coordinate transformations as a means of combining ozone data from different sources to construct daily, synthetic three-dimensional ozone fields. This methodology has been used successfully to reconstruct ozone maps in particular regions from aircraft data over the period of the aircraft campaign. We expand this method to create high-resolution daily global maps of profile ozone data, particularly in the lower stratosphere, where high-resolution ozone data are sparse. Ozone climatologies in PVI-space are constructed from satellite-based SAGE II and UARS/HALOE data, both of which-use solar occultation techniques to make high vertical resolution ozone profile measurements, but with low spatial resolution. A climatology from ground-based balloonsonde data is also created. The climatologies are used to establish the relationship between ozone and dynamical variability, which is defined by the potential vorticity (in the form of equivalent latitude) and potential temperature fields. Once a PVI climatology has been created from data taken by one or more instruments, high-resolution daily profile ozone field estimates are constructed based solely on the PVI fields, which are available on a daily basis from NCEP analysis. These profile ozone maps could be used for a variety of applications, including use in conjunction with total ozone maps to create a daily tropospheric ozone product, as input to forecast models, or as a tool for validating independent ozone measurements when correlative data are not available. This technique is limited to regions where the ozone is a long-term tracer and the flow is adiabatic. We evaluate the internal consistency of the technique by transforming the ozone back to physical space and comparing to the original profiles. Biases in the long-term average of the differences are used to identify regions where the technique is consistently introducing errors. Initial results show

  6. Constructing Synoptic Maps of Stratospheric Column Ozone from HALOE, SAGE and Balloonsonde Data Using Potential Vorticity Isentropic Coordinate Transformations

    NASA Technical Reports Server (NTRS)

    Hollandsworth, Stacey M.; Schoeberl, Mark R.; Morris, Gary A.; Long, Craig; Zhou, Shuntai; Miller, Alvin J.

    1999-01-01

    In this study we utilize potential vorticity - isentropic (PVI) coordinate transformations as a means of combining ozone data from different sources to construct daily, synthetic three-dimensional ozone fields. This methodology has been used successfully to reconstruct ozone maps in particular regions from aircraft data over the period of the aircraft campaign. We expand this method to create high-resolution daily global maps of profile ozone data, particularly in the lower stratosphere, where high-resolution ozone data are sparse. Ozone climatologies in PVI-space are constructed from satellite-based SAGE II and UARS/HALOE data, both of which-use solar occultation techniques to make high vertical resolution ozone profile measurements, but with low spatial resolution. A climatology from ground-based balloonsonde data is also created. The climatologies are used to establish the relationship between ozone and dynamical variability, which is defined by the potential vorticity (in the form of equivalent latitude) and potential temperature fields. Once a PVI climatology has been created from data taken by one or more instruments, high-resolution daily profile ozone field estimates are constructed based solely on the PVI fields, which are available on a daily basis from NCEP analysis. These profile ozone maps could be used for a variety of applications, including use in conjunction with total ozone maps to create a daily tropospheric ozone product, as input to forecast models, or as a tool for validating independent ozone measurements when correlative data are not available. This technique is limited to regions where the ozone is a long-term tracer and the flow is adiabatic. We evaluate the internal consistency of the technique by transforming the ozone back to physical space and comparing to the original profiles. Biases in the long-term average of the differences are used to identify regions where the technique is consistently introducing errors. Initial results show

  7. A Multi-Fluid Compressible System as the Limit of Weak Solutions of the Isentropic Compressible Navier-Stokes Equations

    NASA Astrophysics Data System (ADS)

    Bresch, D.; Huang, X.

    2011-08-01

    This paper mainly concerns the mathematical justification of a viscous compressible multi-fluid model linked to the Baer-Nunziato model used by engineers, see for instance I shii (Thermo-fluid dynamic theory of two-phase flow, Eyrolles, Paris, 1975), under a "stratification" assumption. More precisely, we show that some approximate finite-energy weak solutions of the isentropic compressible Navier-Stokes equations converge, on a short time interval, to the strong solution of this viscous compressible multi-fluid model, provided the initial density sequence is uniformly bounded with corresponding Young measures which are linear convex combinations of m Dirac measures. To the authors' knowledge, this provides, in the multidimensional in space case, a first positive answer to an open question, see H illairet (J Math Fluid Mech 9:343-376, 2007), with a stratification assumption. The proof is based on the weak solutions constructed by D esjardins (Commun Partial Differ Equ 22(5-6):977-1008, 1997) and on the existence and uniqueness of a local strong solution for the multi-fluid model established by H illairet assuming initial density to be far from vacuum. In a first step, adapting the ideas from H off and S antos (Arch Ration Mech Anal 188:509-543, 2008), we prove that the sequence of weak solutions built by D esjardins has extra regularity linked to the divergence of the velocity without any relation assumption between λ and μ. Coupled with the uniform bound of the density property, this allows us to use appropriate defect measures and their nice properties introduced and proved by H illairet (Aspects interactifs de la m'ecanique des fluides, PhD Thesis, ENS Lyon, 2005) in order to prove that the Young measure associated to the weak limit is the convex combination of m Dirac measures. Finally, under a non-degeneracy assumption of this combination ("stratification" assumption), this provides a multi-fluid system. Using a weak-strong uniqueness argument, we prove that

  8. Isentropic compression of argon

    SciTech Connect

    Veeser, L.R.; Ekdahl, C.A.; Oona, H.

    1997-06-01

    The compression was done in an MC-1 flux compression (explosive) generator, in order to study the transition from an insulator to a conductor. Since conductivity signals were observed in all the experiments (except when the probe is removed), both the Teflon and the argon are becoming conductive. The conductivity could not be determined (Teflon insulation properties unknown), but it could be bounded as being {sigma}=1/{rho}{le}8({Omega}cm){sub -1}, because when the Teflon breaks down, the dielectric constant is reduced. The Teflon insulator problem remains, and other ways to better insulate the probe or to measure the conductivity without a probe is being sought.

  9. MODELING AND ANALYSIS OF GLOBAL AND REGIONAL HYDROLOGIC PROCESSES AND APPROPRIATE CONSERVATION OF MOIST ENTROPY

    SciTech Connect

    Donald Johnson, Todd Schaack

    2007-06-08

    The research supported by DOE funding addressed the fundamental issues of understanding and modeling of hydrologic processes in relation to regional and global climate change. The emphasis of this research effort was on the application of isentropic modeling and analysis to advance the accuracy of the simulation of all aspects of the hydrologic cycle including clouds and thus the climate state regionally and globally. Simulation of atmospheric hydrologic processes by the UW hybrid isentropic coordinate models provided fundamental insight into global monsoonal circulations, and regional energy exchange in relation to the atmospheric hydrologic cycle. Inter-comparison of UW hybrid model simulations with those from the NCAR Community Climate Model and other climate and numerical weather prediction (NWP) models investigated the increased accuracies gained in modeling long-range transport in isentropic coordinates and isolated differences in modeling of the climate state. The inter-comparisons demonstrated advantages in the simulation of the transport of the hydrologic components of the climate system and provided insight into the more general problems of simulating hydrologic processes, aerosols and chemistry for climate. This research demonstrated the viability of the UW isentropic-eta model for long-term integration for climate and climate change studies and documented that no insurmountable barriers exist to simulation of climate utilizing hybrid isentropic coordinate models. The results provide impetus for continued development of hybrid isentropic coordinate models as a means to advance accuracies in the simulation of global and regional climate in relation to transport and the planetary distribution of heat sources and sinks.

  10. Simulations of column-averaged CO2 and CH4 using the NIES TM with a hybrid sigma-isentropic (σ-θ) vertical coordinate

    NASA Astrophysics Data System (ADS)

    Belikov, D. A.; Maksyutov, S.; Sherlock, V.; Aoki, S.; Deutscher, N. M.; Dohe, S.; Griffith, D.; Kyro, E.; Morino, I.; Nakazawa, T.; Notholt, J.; Rettinger, M.; Schneider, M.; Sussmann, R.; Toon, G. C.; Wennberg, P. O.; Wunch, D.

    2013-02-01

    We have developed an improved version of the National Institute for Environmental Studies (NIES) three-dimensional chemical transport model (TM) designed for accurate tracer transport simulations in the stratosphere, using a hybrid sigma-isentropic (σ-θ) vertical coordinate that employs both terrain-following and isentropic parts switched smoothly around the tropopause. The air-ascending rate was derived from the effective heating rate and was used to simulate vertical motion in the isentropic part of the grid (above level 350 K), which was adjusted to fit to the observed age of the air in the stratosphere. Multi-annual simulations were conducted using the NIES TM to evaluate vertical profiles and dry-air column-averaged mole fractions of CO2 and CH4. Comparisons with balloon-borne observations over Sanriku (Japan) in 2000-2007 revealed that the tracer transport simulations in the upper troposphere and lower stratosphere are performed with accuracies of ~5% for CH4 and SF6, and ~1% for CO2 compared with the observed volume-mixing ratios. The simulated column-averaged dry air mole fractions of atmospheric carbon dioxide (XCO2) and methane (XCH4) were evaluated against daily ground-based high-resolution Fourier Transform Spectrometer (FTS) observations measured at twelve sites of the Total Carbon Column Observing Network (TCCON) (Bialystok, Bremen, Darwin, Garmisch, Izaña, Lamont, Lauder, Orleans, Park Falls, Sodankylä, Tsukuba, and Wollongong) between January 2009 and January 2011. The comparison shows the model's ability to reproduce the site-dependent seasonal cycles as observed by TCCON, with correlation coefficients typically on the order 0.8-0.9 and 0.4-0.8 for XCO2 and XCH4, respectively, and mean model biases of ±0.2% and ±0.5%, excluding Sodankylä, where strong biases are found. The ability of the model to capture the tracer total column mole fractions is strongly dependent on the model's ability to reproduce seasonal variations in tracer

  11. Fabrication of graded density impactor via underwater shock wave and quasi-isentropic compression testing at two-stage gas gun facility

    NASA Astrophysics Data System (ADS)

    Sun, Wei; Li, Xiaojie; Hokamoto, Kazuyuki

    2014-12-01

    We show direct evidence that underwater shock wave enables us to bond multithin plates with flat, parallel, and high-strength interfaces, which are key requirements for functionally graded material (also called graded density impactor). This phenomenon is ascribed to the super short duration of the high-speed underwater shock wave, reducing the surface tension, diffusion, evaporation, deposition, and viscous flow of matter. Thin magnesium, aluminum, titanium, copper, and molybdenum foils were welded together and designed with the increase in density. Experimental evidence and numerical simulation show that well bonding between the multilayer structures. Microstructure examinations reveal that the dominant interfacial form shifts from waviness to linearity. Graded density impactor with multilayer structure is proved that can produce quasi-isentropic compression in two-stage gas gun experiment with a designed pressure loading profile, which suggests a feasible method to simulate the conditions we want to study that were previously inaccessible in a precisely controlled laboratory environment.

  12. Linear nonequilibrium thermodynamics of reversible periodic processes and chemical oscillations.

    PubMed

    Heimburg, Thomas

    2017-07-05

    Onsager's phenomenological equations successfully describe irreversible thermodynamic processes. They assume a symmetric coupling matrix between thermodynamic fluxes and forces. It is easily shown that the antisymmetric part of a coupling matrix does not contribute to dissipation. Therefore, entropy production is exclusively governed by the symmetric matrix even in the presence of antisymmetric terms. In this paper we focus on the antisymmetric contributions which describe isentropic oscillations with well-defined equations of motion. The formalism contains variables that are equivalent to momenta and coefficients that are analogous to inertial mass. We apply this formalism to simple problems with known answers such as an oscillating piston containing an ideal gas, and oscillations in an LC-circuit. One can extend this formalism to other pairs of variables, including chemical systems with oscillations. In isentropic thermodynamic systems all extensive and intensive variables including temperature can display oscillations reminiscent of adiabatic waves.

  13. Modeling and Analysis of Global and Regional Climate Change in Relation to Atmospheric Hydrologic Processes

    NASA Technical Reports Server (NTRS)

    Johnson, Donald R.

    2001-01-01

    This research was directed to the development and application of global isentropic modeling and analysis capabilities to describe hydrologic processes and energy exchange in the climate system, and discern regional climate change. An additional objective was to investigate the accuracy and theoretical limits of global climate predictability which are imposed by the inherent limitations of simulating trace constituent transport and the hydrologic processes of condensation, precipitation and cloud life cycles.

  14. Existence of global weak solutions to compressible isentropic finitely extensible nonlinear bead-spring chain models for dilute polymers: The two-dimensional case

    NASA Astrophysics Data System (ADS)

    Barrett, John W.; Süli, Endre

    2016-07-01

    We prove the existence of global-in-time weak solutions to a general class of models that arise from the kinetic theory of dilute solutions of nonhomogeneous polymeric liquids, where the polymer molecules are idealized as bead-spring chains with finitely extensible nonlinear elastic (FENE) type spring potentials. The class of models under consideration involves the unsteady, compressible, isentropic, isothermal Navier-Stokes system in a bounded domain Ω in Rd, d = 2, for the density ρ, the velocity u ˜ and the pressure p of the fluid, with an equation of state of the form p (ρ) =cpργ, where cp is a positive constant and γ > 1. The right-hand side of the Navier-Stokes momentum equation includes an elastic extra-stress tensor, which is the classical Kramers expression. The elastic extra-stress tensor stems from the random movement of the polymer chains and is defined through the associated probability density function that satisfies a Fokker-Planck-type parabolic equation, a crucial feature of which is the presence of a centre-of-mass diffusion term. This extends the result in our paper J.W. Barrett and E. Süli (2016) [9], which established the existence of global-in-time weak solutions to the system for d ∈ { 2 , 3 } and γ >3/2, but the elastic extra-stress tensor required there the addition of a quadratic interaction term to the classical Kramers expression to complete the compactness argument on which the proof was based. We show here that in the case of d = 2 and γ > 1 the existence of global-in-time weak solutions can be proved in the absence of the quadratic interaction term. Our results require no structural assumptions on the drag term in the Fokker-Planck equation; in particular, the drag term need not be corotational. With a nonnegative initial density ρ0 ∈L∞ (Ω) for the continuity equation; a square-integrable initial velocity datum u˜0 for the Navier-Stokes momentum equation; and a nonnegative initial probability density function ψ0

  15. Mixing processes within the polar night jet

    NASA Technical Reports Server (NTRS)

    Pierce, R. Bradley; Fairlie, T. Duncan; Grose, William L.; Swinbank, Richard; O'Neill, Alan

    1994-01-01

    Lagrangian material line simulations are performed using U.K. Meteorological Office simulated winds and temperatures to examine mixing processes in the middle- and lower-stratospheric polar night jet during the 1992 Southern Hemisphere spring and Northern Hemisphere winter. The Lagrangian simulations are undertaken to provide insight into the effects of mixing within the polar night jet on observations of the polar vortex made by instruments onboard the Upper Atmosphere Research Satellite (UARS) during these periods. A moderate to strong kinematic barrier to large-scale isentropic exchange, similar to the barrier identified in General Circulation Model (GCM) simulations, is identified during both of these periods. Characteristic timescales for mixing by large-scale isentropic motions within the polar night jet range from 20 days in the Southern Hemisphere lower stratosphere to years in the Northern Hemisphere middle stratosphere. The long mixing timescales found in the Northern Hemisphere polar night jet do not persist. Instead, the Northern Hemisphere kinematic barriers are broken down as part of the large-scale stratospheric response to a strong tropospheric blocking event. A series of Lagrangian experiments are conducted to investigate the sensitivity of the kinematic barrier to diabatic effects and to small-scale inertial gravity wave motions. Differential diabatic descent is found to have a significant impact on mixing processes within the Southern Hemisphere middle-stratospheric jet core. The interaction between small-scale displacements by idealized, inertial gravity waves and the large-scale flow is found to have a significant impact on mixing within the polar night jet in both hemispheres. These sensitivity experiments suggest that scales of motion that are unresolved in global assimilated datasets may contribute to mass exchange across the kinematic barrier to large-scale isentropic motion.

  16. Clear air turbulence as a response to meso- and synoptic-scale dynamic processes

    NASA Technical Reports Server (NTRS)

    Keller, John L.

    1990-01-01

    The paper presents both the Roach equation for the rate of energy dissipation due to clear air turbulence and Richardson number tendencies in isentropic coordinates and examines the implications of these formulations to determine whether there is a dynamic interdependence between Ri and the nonturbulent deformation processes. The equation representing the ln(Ri) tendency is applied diagnostically to grids from an isentropic analysis of archived soundings. The evolution of the Richardson number fields over 12-hour time periods is examined using a mechanistic model. It is suggested that the application of the Roach equation for the turbulent dissipation rate should have a more restricted use. Analyses of the meso-alpha scale Richardson number and of the Richardson number tendency fields reveal a phase relationship consistent with the theoretical predictions.

  17. Clear air turbulence as a response to meso- and synoptic-scale dynamic processes

    NASA Technical Reports Server (NTRS)

    Keller, John L.

    1990-01-01

    The paper presents both the Roach equation for the rate of energy dissipation due to clear air turbulence and Richardson number tendencies in isentropic coordinates and examines the implications of these formulations to determine whether there is a dynamic interdependence between Ri and the nonturbulent deformation processes. The equation representing the ln(Ri) tendency is applied diagnostically to grids from an isentropic analysis of archived soundings. The evolution of the Richardson number fields over 12-hour time periods is examined using a mechanistic model. It is suggested that the application of the Roach equation for the turbulent dissipation rate should have a more restricted use. Analyses of the meso-alpha scale Richardson number and of the Richardson number tendency fields reveal a phase relationship consistent with the theoretical predictions.

  18. Transfer Partial Molar Isentropic Compressibilities of ( l-Alanine/ l-Glutamine/Glycylglycine) from Water to 0.512 {mol} \\cdot {kg}^{-1} Aqueous {KNO}3/0.512 {mol} \\cdot {kg}^{-1} Aqueous {K}2{SO}4 Solutions Between 298.15 K and 323.15 K

    NASA Astrophysics Data System (ADS)

    Riyazuddeen; Gazal, Umaima

    2013-03-01

    Speeds of sound of ( l-alanine/ l-glutamine/glycylglycine + 0.512 {mol}\\cdot {kg}^{-1} aqueous {KNO}3/0.512 {mol}\\cdot {kg}^{-1} aqueous {K}2{SO}4) systems have been measured for several molal concentrations of amino acid/peptide at different temperatures: T = (298.15 to 323.15) K. Using the speed-of-sound and density data, the parameters, partial molar isentropic compressibilities φ _{kappa }0 and transfer partial molar isentropic compressibilities Δ _{tr} φ _{kappa }0, have been computed. The trends of variation of φ _{kappa }0 and Δ _{tr} φ _{kappa }0 with changes in molal concentration of the solute and temperature have been discussed in terms of zwitterion-ion, zwitterion-water dipole, ion-water dipole, and ion-ion interactions operative in the systems.

  19. Isentropic advection and convective lifting of water vapor in the UT - LS as observed over Brazil (22° S) in February 2004 by in situ high-resolution measurements of H2O, CH4, O3 and temperature

    NASA Astrophysics Data System (ADS)

    Durry, G.; Huret, N.; Hauchecorne, A.; Marecal, V.; Pommereau, J.-P.; Jones, R. L.; Held, G.; Larsen, N.; Renard, J.-B.

    2006-12-01

    The micro-SDLA balloonborne diode laser spectrometer was flown twice from Bauru (22° S, Brazil) in February 2004 during HIBISCUS to yield in situ H2O measurements in the Upper Troposphere (UT) and Lower Stratosphere (LS) and in particular in the Tropical Tropopause Layer (TTL). The overall TTL was found warmer (with a subsaturated cold point near -79°C) and the LS moister compared to former measurements obtained in tropical oceanic conditions. The use of specific balloons with a slow descent, combined with the high-resolution of the laser sensor, allowed us to observe in situ in the UT, the TTL and the LS several thin layers correlated on H2O, CH4, O3, temperature and PV. A component of these layers is associated with the isentropic transport into the UT- LS of extratropical stratospheric air masses. Moreover, the examination of temperature and tracer (CH4, O3) profiles gives insights on the potential contribution of convective transport of H2O in the TTL.

  20. Seasonal dependence of the long-range transport and vertical distribution of free tropospheric aerosols over east Asia: On the basis of aircraft and lidar measurements and isentropic trajectory analysis

    NASA Astrophysics Data System (ADS)

    Matsuki, Atsushi; Iwasaka, Yasunobu; Osada, Kazuo; Matsunaga, Katsuji; Kido, Mizuka; Inomata, Yayoi; Trochkine, Dmitri; Nishita, Chiharu; Nezuka, Takayoshi; Sakai, Tetsu; Zhang, Daizhou; Kwon, Soung-An

    2003-12-01

    Seasonal changes in the vertical structure of free tropospheric aerosols over east Asia, on the basis of aircraft-borne and lidar measurements, and on the pathway of the long-range transport of Asian dust particles inferred from isentropic trajectory analysis are discussed. Aircraft-borne measurements held in situ in the free troposphere over central Japan in 2000-2001 revealed a small in scale yet steady transport of dust in the lower-middle free troposphere (2-6 km altitude) during spring including days with no evident dust outbreak. Such dust, found as background, was observed even in summer in the regions higher than 4 km under the influence of remaining westerly winds but not in the lower regions. From a series of lidar observations over Nagoya (35°N, 137°E), Japan, noticeable changes in aerosol characteristics were obtained in the free troposphere from spring to summer. Taklimakan desert is suggested as possible important source of the background dust.

  1. Implications for Uranus and Neptune of Electrical Conductivities of Fluid Hydrogen, Water, and Synthetic Uranus Measured Under Dynamic Quasi-Isentropic Compression up to 180 GPa and Several 1000 K

    NASA Astrophysics Data System (ADS)

    Nellis, W. J.

    2014-12-01

    Electrical conductivities of metallic fluid H and ionic fluids H2O and Synthetic Uranus (SU) have been measured experimentally under dynamic quasi-isentropic compression up to 180 GPa and several 1000 K. SU is a mixture of H2O, NH3 and C3H8O with composition representative of "Ice". Pressures P and temperatures T of the conductivity experiments were similar to P and T in interiors of Uranus and Neptune (U/N). Fluid H semiconducts at ~90 GPa and becomes a degenerate fluid metal with conductivity 2000/(ohm-cm) at 140 GPa, 0.64 g/cm3 and T/TF~0.01, where TF is Fermi temperature, conditions near the envelope/core boundaries of U/N. Metallization density is within a few% of the insulator-metal transition predicted by Wigner and Huntington in 1935. SU and water have conductivities of ~100/(ohm-cm) at 150 GPa. Podolak et al have shown a mixture of 75% Rock-25% Gas (by mass) behaves similarly to "pure" Ice in region that encompasses most mass of Uranus. The bandgap of water is predicted to close at 300 GPa and ~7000 K by Cavazonni et al. Models of pressure, temperature and density in U/N based on Voyager II gravity data have been developed by Helled et al. Stanley and Bloxham (SB) have developed MHD models that calculate non-dipolar and non-axisymmetric magnetic fields similar to those of U/N. The MHD models of SB assume that materials at planetary radii below the thin-shell dynamos that make the magnetic fields are stably stratified. The purpose of this paper is to develop a common picture for the deep interiors of U/N based on Voyager II gravity and magnetic data, measured electrical conductivities of planetary fluids, theoretical computations of interior conditions and the likely source of unusual magnetic fields, and extrapolation of existing experimental data for materials at 180 GPa to greater planetary depths. Main conclusions are the magnetic fields of U/N are probably made primarily by fluid metallic H at radii out to ~0.8 or more of U/N outer radii. Most of the

  2. Diabatic processes and the evolution of two contrasting extratropical cyclones

    NASA Astrophysics Data System (ADS)

    Martinez-Alvarado, Oscar; Gray, Suzanne; Methven, John

    2016-04-01

    Two contrasting extratropical cyclones were observed over the United Kingdom during the summer 2012 field campaign of the DIAMET (DIAbatic influences on Mesoscale structures in ExtraTropical storms) project. The first cyclone, observed in July, was a shallow system typical of summer over west Europe while the second cyclone, observed in August, was a much deeper system which developed a potential vorticity (PV) tower. The evolution of these two cyclones was analysed and compared in terms of diabatic effects with respect to two aspects. The first aspect is the amount and distribution of heat produced during the development of each cyclone, measured by the cross-isentropic motion around the cyclone centre. The second aspect is the modification to the circulation around the cyclones' centres, measured by area-averaged isentropic vorticity. The contributions from individual diabatic processes, such as convection, cloud microphysics and radiation, to these two aspects is also considered. The cyclones were analysed via hindcast simulations with a research version of the Met Office Unified Model, enhanced with on-line tracers of diabatic changes of potential temperature and PV. A new methodology for the interpretation of these tracers was also implemented and used. The hindcast simulations were compared with the available dropsonde observations from the field campaign as well as operational analyses and radar rainfall rates. It is shown that, while boundary layer and turbulent mixing processes and cloud microphysics processes contributed to the development of both cyclones, the main differences between the cyclones in terms of diabatic effects could be attributed to differences in convective activity. It is also shown that the contribution from all these diabatic processes to changes in the circulation was modulated by the characteristics of advection around each cyclone in a highly nonlinear fashion. This research establishes a new framework for a systematic comparison

  3. Impact and collisional processes in the solar system

    NASA Technical Reports Server (NTRS)

    Ahrens, T. J.

    1985-01-01

    The mechanical and thermodynamic aspects of shock impact cratering and accretionary processes on solid planets and satellites are being investigated experimentally. The recently proposed model of Melosh, describing the physics controlling the size and velocity of only lightly shocked spalled ejecta surrounding the crushed rock region of an impact crater, was studied at the Ames gun facility. Spall velocity measurements using lead and aluminum bullets were conducted. In addition, shock temperatures of silicates and volatile-bearing minerals were measured using radiative techniques. Finally impact devolatilization of minerals and accretion of planetary atmospheres were examined. Measurements of the release isentropes of CaCO3 were carried out. The effect on the water budgets of planets of reactions which occur when metallic iron (which would be present in chondritic material) is introduced into a simple accretion model is under investigation.

  4. Impact and Collisional Processes in the Solar System

    NASA Technical Reports Server (NTRS)

    Ahrens, T. J.

    1985-01-01

    The mechanical and thermodynamic aspects of shock impact cratering and accretionary processes on solid planets and satellites are being investigated experimentally. The recently proposed model of Melosh, describing the physics controlling the size and velocity of only lightly shocked spalled ejecta surrounding the crushed rock region of an impact crater, was studied at the Ames gun facility. Spall velocity measurements using lead and aluminum bullets were conducted. In addition, shock temperatures of silicates and volatile bearing minerals were measured using radiative techniques. Finally impact devolatilization of minerals and accretion of planetary atmospheres were examined. Measurements of the release isentropes of CaCO3 were carried out. The effect on the water budgets of planets of reactions which occur when metallic iron (which would be present in chondritic material) is introduced into a simple accretion model is under investigation.

  5. Transient processes in the combustion of nitramine propellants

    NASA Technical Reports Server (NTRS)

    Cohen, N. S.; Strand, L. D.

    1978-01-01

    A transient combustion model of nitramine propellants is combined with an isentropic compression shock formation model to determine the role of nitramine propellant combustion in DDT, excluding effects associated with propellant structural properties or mechanical behavior. The model is derived to represent the closed pipe experiment that is widely used to characterize explosives, except that the combustible material is a monolithic charge rather than compressed powder. Computations reveal that the transient combustion process cannot by itself produce DDT by this model. Compressibility of the solid at high pressure is the key factor limiting pressure buildups created by the combustion. On the other hand, combustion mechanisms which promote pressure buildups are identified and related to propellant formulation variables. Additional combustion instability data for nitramine propellants are presented. Although measured combustion response continues to be low, more data are required to distinguish HMX and active binder component contributions. A design for a closed vessel apparatus for experimental studies of high pressure combustion is discussed.

  6. Transport processes in the stratosphere: Model simulations and comparisons with satellite observations

    NASA Technical Reports Server (NTRS)

    Grose, W. L.; Turner, R. E.; Nealy, J. E.

    1985-01-01

    A three dimensional atmospheric model was used to study transport processes and to simulate the distribution of chemically active species in the stratosphere. The present results are part of a long term simulation of the seasonally varying structure of stratospheric trace constituents. The occurrence of a midwinter stratospheric warming and the associated transport of O3 and HNO3 during the simulation are described. Comparison of the simulated distributions of O3 and HNO3 are made with data from the Limb Infrared Monitor of the Stratosphere (LIMS) experiment. In addition, distributions of Ertel's potential vorticity on isentropic surfaces (IPV) are evaluated as a diagnostic for interpreting transport processes. Comparisons are made with IPV distributions inferred from LIMS temperature data.

  7. Coupling Processes Between Atmospheric Chemistry and Climate

    NASA Technical Reports Server (NTRS)

    Ko, M. K. W.; Weisenstein, Debra; Shia, Run-Li; Sze, N. D.

    1997-01-01

    This is the first semi-annual report for NAS5-97039 summarizing work performed for January 1997 through June 1997. Work in this project is related to NAS1-20666, also funded by NASA ACMAP. The work funded in this project also benefits from work at AER associated with the AER three-dimensional isentropic transport model funded by NASA AEAP and the AER two-dimensional climate-chemistry model (co-funded by Department of Energy). The overall objective of this project is to improve the understanding of coupling processes between atmospheric chemistry and climate. Model predictions of the future distributions of trace gases in the atmosphere constitute an important component of the input necessary for quantitative assessments of global change. We will concentrate on the changes in ozone and stratospheric sulfate aerosol, with emphasis on how ozone in the lower stratosphere would respond to natural or anthropogenic changes. The key modeling tools for this work are the AER two-dimensional chemistry-transport model, the AER two-dimensional stratospheric sulfate model, and the AER three-wave interactive model with full chemistry.

  8. The mesoscale forcing of a midlatitude upper-tropospheric jet streak by a simulated convective system. 1: Mass circulation and ageostrophic processes

    NASA Technical Reports Server (NTRS)

    Wolf, Bart J.; Johnson, D. R.

    1995-01-01

    The mutual forcing of a midlatitude upper-tropospheric jet streak by organized mesoscale adiabatic and diabatic processes within a simulated convective system (SCS) is investigated. Using isentropic diagnostics, results from a three-dimensional numerical simulation of an SCS are examined to study the isallobaric flow field, modes of dominant ageostrophic motion, and stability changes in relation to the mutual interdependence of adiabatic processes and latent heat release. Isentropic analysis affords an explicit isolation of a component of isallobaric flow associated with diabatic processes within the SCS. Prior to convective development within the simulations, atmospheric destabilization occurs through adiabatic ageostrophic mass adjustment and low-level convergence in association with the preexisting synoptic-scale upper-tropospheric jet streak. The SCS develops in a baroclinic zone and quickly initiates a vigorous mass circulation. By the mature stage, a pronounced vertical couplet of low-level convergence and upper-level mass divergence is established, linked by intense midtropospoheric diabatic heating. Significant divergence persists aloft for several hours subsequent to SCS decay. The dominant role of ageostrophic motion within which the low-level mass convergence develops is the adiabatic isallobaric component, while the mass divergence aloft develops principally through the diabatic isallobaric component. Both compnents are intrinsically linked to the convectively forced vertical mass transport. The inertial diabatic ageostrophic component is largest near the level of maximum heating and is responsible for the development of inertial instability to the north of SCS, resulting in this quadrant being preferred for outflow. The inertial advective component, the dominant term that produces the new downstream wind maximum, rapidly develops north of the SCS and through mutual adjustment creates the baroclinic support for the new jet streak.

  9. Moisture origin and transport processes in Colombia, northern South America

    NASA Astrophysics Data System (ADS)

    Hoyos, I.; Dominguez, F.; Cañón-Barriga, J.; Martínez, J. A.; Nieto, R.; Gimeno, L.; Dirmeyer, P. A.

    2017-04-01

    We assess the spatial structure of moisture flux divergence, regional moisture sources and transport processes over Colombia, in northern South America. Using three independent methods the dynamic recycling model (DRM), FLEXPART and the Quasi-isentropic back-trajectory (QIBT) models we quantify the moisture sources that contribute to precipitation over the region. We find that moisture from the Atlantic Ocean and terrestrial recycling are the most important sources of moisture for Colombia, highlighting the importance of the Orinoco and Amazon basins as regional providers of atmospheric moisture. The results show the influence of long-range cross-equatorial flow from the Atlantic Ocean into the target region and the role of the study area as a passage of moisture into South America. We also describe the seasonal moisture transport mechanisms of the well-known low-level westerly and Caribbean jets that originate in the Pacific Ocean and Caribbean Sea, respectively. We find that these dynamical systems play an important role in the convergence of moisture over western Colombia.

  10. Isentropic Bulk Modulus: Development of a Federal Test Method

    DTIC Science & Technology

    2016-01-01

    ranging from 30-80 °C and applied pressures of 1,000-18,000 psi. This method has been applied successfully to aviation turbine fuels and diesel fuels...pressures of 1,000-18,000 psi. This method has been applied successfully to aviation turbine fuels and diesel fuels composed of petroleum, synthetic...successfully to aviation turbine fuels and diesel fuels composed of petroleum, synthetic, and alternative feedstocks. Bulk Modulus, currently referenced as

  11. Sound Generation in the Interaction of Two Isentropic Vortices

    DTIC Science & Technology

    2012-02-02

    difference in their spacial scales. Mu = −0.8, Md = 0.25, d = 2.2, rcu = 1 and rcd = 0.2. 11 X S o u n d P re ss u re -200 -100 0 100 200 -0.0004 -0.0002 0...counter-rotating vortices in the case of Mu = −0.5, Md = 0.5, d = 2.2, rcu = 1 and rcd = 0.2. References [1] Lighthill M. J. (1952). On sound generated

  12. Nonideal isentropic gas flow through converging-diverging nozzles

    NASA Technical Reports Server (NTRS)

    Bober, W.; Chow, W. L.

    1990-01-01

    A method for treating nonideal gas flows through converging-diverging nozzles is described. The method incorporates the Redlich-Kwong equation of state. The Runge-Kutta method is used to obtain a solution. Numerical results were obtained for methane gas. Typical plots of pressure, temperature, and area ratios as functions of Mach number are given. From the plots, it can be seen that there exists a range of reservoir conditions that require the gas to be treated as nonideal if an accurate solution is to be obtained.

  13. Development of a Test Rig for Measuring Isentropic Bulk Modulus

    DTIC Science & Technology

    2013-01-01

    biodiesel samples are also significantly higher than the aviation fuels. Although not discernible from this data, the speed-of-sound for blends of...variety of petroleum-based and alternative fuels were used in this effort. All of the alternative aviation fuels and their blends were provided by AFRL...WPAFB). The petroleum-based fuels and biodiesels were on-hand at SwRI. 5.0 APPARATUS 5.1 INSTRUMENTATION The instrumentation required to

  14. Computation of Non-Isentropic Internal Flows with Variable Density

    DTIC Science & Technology

    1993-11-01

    development has been focused on the aerothermodynamics aspects of the code. Development of the reactive flow facilities ( chemistry , kinetics) should now...Journal, Vol 27, NO 9, Pages 1167-1174, September 1989. 5 HUGHES, W. F., and BRIGHTON, J. A.; "Fluid Dynamics", Schaum Pub. Co., New 0 York, 1967. 6

  15. Numerical Simulation of the Working Process in the Twin Screw Vacuum Pump

    NASA Astrophysics Data System (ADS)

    Lu, Yang; Fu, Yu; Guo, Bei; Fu, Lijuan; Zhang, Qingqing; Chen, Xiaole

    2017-08-01

    Twin screw vacuum pumps inherit the advantages of screw machinery, such as high reliability, stable medium conveying, small vibration, simple and compact structures, convenient operation, etc, which have been widely used in petrochemical and air industry. On the basis of previous studies, this study analyzed the geometric features of variable pitch of the twin screw vacuum pump such as the sealing line, the meshing line and the volume between teeth. The mathematical model of numerical simulation of the twin screw vacuum pump was established. The leakage paths of the working volume including the sealing line and the addendum arc were comprehensively considered. The corresponding simplified geometric model of leakage flow was built up for different leak paths and the flow coefficients were calculated. The flow coefficient value range of different leak paths was given. The results showed that the flow coefficient of different leak paths can be taken as constant value for the studied geometry. The analysis of recorded indicator diagrams showed that the increasing rotational speed can dramatically decrease the exhaust pressure and the lower rotational speed can lead to over-compression. The pressure of the isentropic process which was affected by leakage was higher than the theoretical process.

  16. Diabatic processes and the evolution of two contrasting extratropical cyclones

    NASA Astrophysics Data System (ADS)

    Methven, John; Martinez-Alvarado, Oscar; Gray, Suzanne

    2017-04-01

    Extratropical cyclones are typically weaker and less frequent in summer as a result of differences in the background state flow and diabatic processes with respect to other seasons. Two extratropical cyclones were observed in summer 2012 with a research aircraft during the DIAMET (DIAbatic influences on Mesoscale structure in ExTratropical storms) field campaign. The first cyclone deepened only down to 995 hPa; the second cyclone deepened down to 978 hPa and formed a potential vorticity (PV) tower, a frequent signature of intense cyclones. The cyclones were analyzed through numerical simulations incorporating tracers for the effects of diabatic processes on potential temperature and PV. It was found that the observed maximum vapor flux in the stronger cyclone was twice as strong as in the weaker cyclone; the water vapor mass flow along the warm conveyor belt of the stronger cyclone was over half that typical in winter even though the flow was weaker. Did the greater water transport and latent heat release associated with condensation result in the greater circulation in the PV tower case? A cyclone-centred integral framework is introduced relating the tracers with cross-isentropic mass transport and circulation around the cyclone. It is shown that the circulation increases much more slowly than the amplitude of the diabatically-generated PV tower at its centre. This effect is explained using the PV impermeability theorem and the influence of diabatic heating on circulation around a cyclone is shown to scale with Rossby number. The implication is that the stronger a cyclone becomes (larger Rossby number), the stronger the influence of latent heating on circulation.

  17. Cycle Engine Modelling Of Spark Ignition Engine Processes during Wide-Open Throttle (WOT) Engine Operation Running By Gasoline Fuel

    NASA Astrophysics Data System (ADS)

    Rahim, M. F. Abdul; Rahman, M. M.; Bakar, R. A.

    2012-09-01

    One-dimensional engine model is developed to simulate spark ignition engine processes in a 4-stroke, 4 cylinders gasoline engine. Physically, the baseline engine is inline cylinder engine with 3-valves per cylinder. Currently, the engine's mixture is formed by external mixture formation using piston-type carburettor. The model of the engine is based on one-dimensional equation of the gas exchange process, isentropic compression and expansion, progressive engine combustion process, and accounting for the heat transfer and frictional losses as well as the effect of valves overlapping. The model is tested for 2000, 3000 and 4000 rpm of engine speed and validated using experimental engine data. Results showed that the engine is able to simulate engine's combustion process and produce reasonable prediction. However, by comparing with experimental data, major discrepancy is noticeable especially on the 2000 and 4000 rpm prediction. At low and high engine speed, simulated cylinder pressures tend to under predict the measured data. Whereas the cylinder temperatures always tend to over predict the measured data at all engine speed. The most accurate prediction is obtained at medium engine speed of 3000 rpm. Appropriate wall heat transfer setup is vital for more precise calculation of cylinder pressure and temperature. More heat loss to the wall can lower cylinder temperature. On the hand, more heat converted to the useful work mean an increase in cylinder pressure. Thus, instead of wall heat transfer setup, the Wiebe combustion parameters are needed to be carefully evaluated for better results.

  18. The Interaction of Radiative and Dynamical Processes during a Simulated Sudden Stratospheric Warming.

    NASA Astrophysics Data System (ADS)

    Pierce, R. B.; Blackshear, W. T.; Fairlie, T. D.; Grose, W. L.; Turner, R. E.

    1993-12-01

    An analysis of a spontaneous sudden stratospheric warming that occurred during a 2-year integration of the Langley Research Center Atmospheric Simulation Model is presented. The simulated warming resembles observed `wave 1' warmings in the Northern Hemisphere stratosphere and provides an opportunity to investigate the radiative and dynamical processes occurring during the warming event. Isentropic analysis of potential vorticity sources and sinks indicates that dynamically induced departures from radiative equilibrium play an important role in the warming event. Enhanced radiative cooling associated with a series of upper stratospheric warm pools leads to radiative dampening within the polar vortex. Within the `surf zone' large-scale radiative cooling leads to diabatic advection of high potential vorticity air from aloft. Lagrangian area diagnostics of the simulated warming agree well with LIMS analyses. Dynamical mixing is shown to account for the majority of the decrease in the size of the polar vortex during the simulated warming. An investigation of the nonlinear deformation of material lines that are initially coincident with diagnosed potential vorticity isopleths is conducted to clarify the relationship between the Lagrangian area diagnostics and potential vorticity advection during wave breaking events.

  19. Constant entropy sampling and release waves of shock compressions

    NASA Astrophysics Data System (ADS)

    Maillet, Jean-Bernard; Bourasseau, Emeric; Soulard, Laurent; Clérouin, Jean; Stoltz, Gabriel

    2009-08-01

    We present or recall several equilibrium methods that allow one to compute isentropic processes, either during the compression or the release of the material. These methods are applied to compute the isentropic release of a shocked monoatomic liquid at high pressure and temperature. Moreover, equilibrium results of isentropic release are compared to the direct nonequilibrium simulation of the same process. We show that due to the viscosity of the liquid but also to nonequilibrium effects, the release of the system is not strictly isentropic.

  20. Budgeting Process

    ERIC Educational Resources Information Center

    Hentschke, Guilbert C.; Shaughnessy, John

    1973-01-01

    Attempts to describe the budgeting process in school districts. Discusses general budget calendars and explains the process of constructing a Program Evaluation and Review Technique (PERT) chart of the budgeting process. Presents a detailed list of activities to be included in the budgeting process and a PERT chart indicating how these activities…

  1. Meat Processing.

    ERIC Educational Resources Information Center

    Legacy, Jim; And Others

    This publication provides an introduction to meat processing for adult students in vocational and technical education programs. Organized in four chapters, the booklet provides a brief overview of the meat processing industry and the techniques of meat processing and butchering. The first chapter introduces the meat processing industry and…

  2. Use of GTE, Mozaic, Sonex, and UARS-MLS Data in Understanding Tropospheric Processes Critical to Model Development

    NASA Technical Reports Server (NTRS)

    Newell, Reginald E. (Principal Investigator)

    2003-01-01

    During the first year we focused on the analysis of data collected on over 7600 commercial aircraft flights (the MOZAIC program). The aim was to further our understanding of the fundamental dynamical processes that drive mesoscale phenomena in the upper troposphere and lower stratosphere, and their effects on the advection of passive scalars. Through these studies we made the following findings. 2001]: We derived the Kolmogorov equation for the third-order velocity structure function on an f-plane. We showed how the sign of the function yields the direction of the energy cascade. The remarkable linearity of the measured off diagonal third-order structure function was studied. We suggested that the Coriolis term, which appears explicitly in this equation, may be crucial in understanding the observed kinetic energy spectra at scales larger than 100 km, instead of the nonlinear advection term as previously assumed. Also, we showed that decreases with latitude for mid- to high-latitudes, and tabulated the values. Ozone concentration structure functions were calculated by restricting the data points to approximately isentropic pairings. In this way we were able to make comparisons with scalar advection theories. We found that, at even the largest scales, there was no evidence for the simple scaling predicted for smooth advection/diffusion.

  3. Meteorological Processes Affecting the Transport of Emissions from the Navajo Generating Station to Grand Canyon National Park.

    NASA Astrophysics Data System (ADS)

    Lindsey, Charles G.; Chen, Jun; Dye, Timothy S.; Willard Richards, L.; Blumenthal, Donald L.

    1999-08-01

    During the 1990 Navajo Generating Station (NGS) Winter Visibility Study, a network of surface and upper-air meteorological measurement systems was operated in and around Grand Canyon National Park to investigate atmospheric processes in complex terrain that affected the transport of emissions from the nearby NGS. This network included 15 surface monitoring stations, eight balloon sounding stations (equipped with a mix of rawinsonde, tethersonde, and Airsonde sounding systems), three Doppler radar wind profilers, and four Doppler sodars. Measurements were made from 10 January through 31 March 1990. Data from this network were used to prepare objectively analyzed wind fields, trajectories, and streak lines to represent transport of emissions from the NGS, and to prepare isentropic analyses of the data. The results of these meteorological analyses were merged in the form of a computer animation that depicted the streak line analyses along with measurements of perfluorocarbon tracer, SO2, and sulfate aerosol concentrations, as well as visibility measurements collected by an extensive surface monitoring network. These analyses revealed that synoptic-scale circulations associated with the passage of low pressure systems followed by the formation of high pressure ridges accompanied the majority of cases when NGS emittants appeared to be transported to the Grand Canyon. The authors' results also revealed terrain influences on transport within the topography of the study area, especially mesoscale flows inside the Lake Powell basin and along the plain above the Marble Canyon.

  4. Use of GTE, Mozaic, Sonex, and UARS-MLS Data in Understanding Tropospheric Processes Critical to Model Development

    NASA Technical Reports Server (NTRS)

    Newell, Reginald E. (Principal Investigator)

    2003-01-01

    During the first year we focused on the analysis of data collected on over 7600 commercial aircraft flights (the MOZAIC program). The aim was to further our understanding of the fundamental dynamical processes that drive mesoscale phenomena in the upper troposphere and lower stratosphere, and their effects on the advection of passive scalars. Through these studies we made the following findings. 2001]: We derived the Kolmogorov equation for the third-order velocity structure function on an f-plane. We showed how the sign of the function yields the direction of the energy cascade. The remarkable linearity of the measured off diagonal third-order structure function was studied. We suggested that the Coriolis term, which appears explicitly in this equation, may be crucial in understanding the observed kinetic energy spectra at scales larger than 100 km, instead of the nonlinear advection term as previously assumed. Also, we showed that decreases with latitude for mid- to high-latitudes, and tabulated the values. Ozone concentration structure functions were calculated by restricting the data points to approximately isentropic pairings. In this way we were able to make comparisons with scalar advection theories. We found that, at even the largest scales, there was no evidence for the simple scaling predicted for smooth advection/diffusion.

  5. Wake Interaction Effects on the Transition Process on Turbine Blades

    DTIC Science & Technology

    1989-09-01

    Ainsworth J. E. LaGraff Dept. of Engineering Science Dept. of Mechanical and Oxford University Aerospace Engineerinm Oxfoid, England, OXI 3PJ Syracuse...D rotating single stage environment. EXPERIMENTAL SET-UP The main experimental facility used was the Oxford University Isentropic Light Piston Tunnel...Aerodynamics and Heat Transfer in a Transonic Turbine Stc 6 e," D. Phil Thesis, Oxford University , 1987. 10. Ashworth, D.A. and LaGraff, J.E

  6. Science Processes.

    ERIC Educational Resources Information Center

    Finley, Fred N.

    1983-01-01

    Reports an investigation of the epistomologic foundations of Gagne's conception of science processes. Results indicate that a commitment to inductive empiricism pervades the presently held view of science processes. Implications for science education are considered. (Author/JN)

  7. Shuttle Processing

    NASA Technical Reports Server (NTRS)

    Guodace, Kimberly A.

    2010-01-01

    This slide presentation details shuttle processing flow which starts with wheel stop and ends with launching. The flow is from landing the orbiter is rolled into the Orbiter Processing Facility (OPF), where processing is performed, it is then rolled over to the Vehicle Assembly Building (VAB) where it is mated with the propellant tanks, and payloads are installed. A different flow is detailed if the weather at Kennedy Space Center requires a landing at Dryden.

  8. ASCOT process

    SciTech Connect

    Bonilla, J.A.

    1985-12-01

    Foster Wheeler is developing the ASCOT (Asphalt Coking Technology) process which combines a modified solvent deasphalting (SDA) unit, using heavy solvents, with a delayed coking (DC) unit for the upgrade of heavy oils into intermediate products suitable for processing in conventional refinery units, to produce high quality distillate products. This paper presents a description of the ASCOT process and its application to the upgrade of San Joaquin vacuum residue. The ASCOT process is then compared to the independent applications of DC and SDA. 6 references.

  9. Peat Processing

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Humics, Inc. already had patented their process for separating wet peat into components and processing it when they consulted NERAC regarding possible applications. The NERAC search revealed numerous uses for humic acid extracted from peat. The product improves seed germination, stimulates root development, and improves crop yields. There are also potential applications in sewage disposal and horticultural peat, etc.

  10. Process description

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The production of hydrogen from coal by hydrogasification and subsequent steam hydrocarbon reforming was studied. Process heat and power requirements are supplied by an HTGR. The process is examined as a function of a maximum reforming (process) temperature of 922 K (1200 F) to 1367 K (2000 F). The major parameters for the five cases selected are summarized in a table. A fixed thermal capacity of 3000 MW for the HTGR heat source was used as a basis. The resulting hydrogen production rates and the corresponding hydrogen purity are also given in a table.

  11. Recovery process

    SciTech Connect

    Apffel, F.

    1989-06-13

    This patent describes a process for manufacturing char and hydrocarbons from discarded used tires. The process consists of: introducing the substantially whole tires into a reactor; pyrolyzing the substantially whole tires in a reaction chamber continuously at a temperature and pressure and for a reaction time sufficient to cause the tires to dissociate into a vapor and a solid phase; the pyrolyzing step including directly heating the tires with a radiant heat source at temperatures of 1000{sup 0} to 3000{sup 0}F; producing char from the solid phase; and processing the vapor phase to produce hydrocarbons.

  12. Processible Polyazomethines

    NASA Technical Reports Server (NTRS)

    Bryant, Robert G.

    1993-01-01

    Processibility enhanced by incorporating trifluoromethylbenzene units into molecules. Results of two unexpected properties: high solubility in common organic solvents and lack of crystallinity. Properties coupled with ability of this class of polymers to undergo exchange reactions at elevated temperatures allow these materials to moderate their molecular weights during processing, which affects resulting mechanical properties after processing. Fluorinated polyazomethines form amorphous films that have excellent mechanical properties. Used in moisture-free environments as electronic semiconducting films and adhesives, and as matrix resins for advanced structural composites.

  13. Word Processing.

    ERIC Educational Resources Information Center

    McWilliams, Peter

    1982-01-01

    Describes the kinds of computer equipment needed for a personal word processing system. The characteristics and capabilities of specific devices, including keyboards, printers, and disk drives, are discussed. (JL)

  14. Manufacturing processes

    NASA Technical Reports Server (NTRS)

    Bennet, Jay; Brower, David; Levine, Stan; Walker, Ray; Wooten, John

    1991-01-01

    The following issues are covered: process development frequently lags behind material development, high fabrication costs, flex joints (bellows) - a continuing program, SRM fabrication-induced defects, and in-space assembly will require simplified design.

  15. Grants Process

    Cancer.gov

    The NCI Grants Process provides an overview of the end-to-end lifecycle of grant funding. Learn about the types of funding available and the basics for application, review, award, and on-going administration within the NCI.

  16. Anodizing Process

    NASA Technical Reports Server (NTRS)

    1983-01-01

    This anodizing process traces its origin to the 1960's when Reynolds Metals Company, under contract with Goddard Space Flight Center, developed a multipurpose anodizing electrolyte (MAE) process to produce a hard protective finish for spacecraft aluminum. MAE produces a high-density, abrasion-resistant film prior to the coloring step, in which the pores of the film are impregnated with a metallic form of salt. Tru-Color product applications include building fronts, railing, curtain walls, doors and windows.

  17. Multifractal Processes

    DTIC Science & Technology

    1999-01-01

    Processes 1 Introduction and Summary Fractal processes have been instrumental in a variety of fields ranging from the theory of fully developed...formalism in a stochastic setting . Thereby, the importance of higher order statistics will become evident. It might be especially appealing to the...rates occur in multifractal ‘trading time’ [68, 69]. With the theory developed in this paper, it be- comes an easy task to explore B1/2(M(t)) from the

  18. Power processing

    NASA Technical Reports Server (NTRS)

    Schwarz, F. C.

    1971-01-01

    Processing of electric power has been presented as a discipline that draws on almost every field of electrical engineering, including system and control theory, communications theory, electronic network design, and power component technology. The cost of power processing equipment, which often equals that of expensive, sophisticated, and unconventional sources of electrical energy, such as solar batteries, is a significant consideration in the choice of electric power systems.

  19. Organosolv Processes.

    PubMed

    Brosse, Nicolas; Hussin, Mohd Hazwan; Rahim, Afidah Abdul

    2017-03-10

    Biofuels and chemicals can be produced from lignocellulosic feedstocks using biotechnological processes. The effective utilization of carbohydrates from biomass for the production of biofuels necessitates the development of pretreatment technologies to enhance their enzymatic digestibility. Among all the various pretreatment methods currently studied and developed, the organosolv processes, in which organic solvents or aqueous organic solvent mixtures are used as the pretreatment medium, appear to be specially promising in the context of the biorefinery because (1) they produce cellulosic pulp with a good enzymatic digestibility for monomeric glucose production and (2) they allow a clean fractionation of the major biomass components (cellulose, lignin, and hemicelluloses) into three process streams. In this chapter we give an updated overview of organosolv methods using conventional solvents and ionic liquids which have recently gained considerable interest as solvents for lignocellulosic biomass and pretreatment.

  20. Process Analyzer

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The ChemScan UV-6100 is a spectrometry system originally developed by Biotronics Technologies, Inc. under a Small Business Innovation Research (SBIR) contract. It is marketed to the water and wastewater treatment industries, replacing "grab sampling" with on-line data collection. It analyzes the light absorbance characteristics of a water sample, simultaneously detects hundreds of individual wavelengths absorbed by chemical substances in a process solution, and quantifies the information. Spectral data is then processed by ChemScan analyzer and compared with calibration files in the system's memory in order to calculate concentrations of chemical substances that cause UV light absorbance in specific patterns. Monitored substances can be analyzed for quality and quantity. Applications include detection of a variety of substances, and the information provided enables an operator to control a process more efficiently.

  1. Reforming process

    SciTech Connect

    Mitsche, R.T.; Pope, G.N.

    1981-01-06

    A process for reforming a naphtha feedstock is disclosed. The reforming process is effected at reforming conditions in contact with a catalyst comprising a platinum group metal component and a group iv-a metal component composited with an alumina support wherein said support is prepared by admixing an alpha alumina monohydrate with an aqueous ammoniacal solution having a ph of at least about 7.5 to form a stable suspension. A salt of a strong acid, e.g., aluminum nitrate, is commingled with the suspension to form an extrudable paste or dough. On extrusion, the extrudate is dried and calcined to form said alumina support.

  2. FLUORINATION PROCESS

    DOEpatents

    McMillan, T.S.

    1957-10-29

    A process for the fluorination of uranium metal is described. It is known that uranium will react with liquid chlorine trifluoride but the reaction proceeds at a slow rate. However, a mixture of a halogen trifluoride together with hydrogen fluoride reacts with uranium at a significantly faster rate than does a halogen trifluoride alone. Bromine trifluoride is suitable for use in the process, but chlorine trifluoride is preferred. Particularly suitable is a mixture of ClF/sub 3/ and HF having a mole ratio (moles

  3. Point Processes.

    DTIC Science & Technology

    1987-05-01

    ClaSIfication , 0.1102F 2304 Point processes____________ 12. PERSONAL AUTHORIS) Serfozo, R.F. 13AL TYPE OF REPORT 13b. TIME COVERED I4. DATE OF REPORT...the Laplace functional of M is as in Lemma 1.12. Keep in mind that a typical representation of a marked point process is o V 4 =. 1 6XnZ where N = 2 6...special case, for f: A - R . is X E[f(NO)] = E[JO f(O N)dt]. 0 Keep in mind that the expectation on the left is with respect to the probability for N

  4. Image Processing

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Images are prepared from data acquired by the multispectral scanner aboard Landsat, which views Earth in four ranges of the electromagnetic spectrum, two visible bands and two infrared. Scanner picks up radiation from ground objects and converts the radiation signatures to digital signals, which are relayed to Earth and recorded on tape. Each tape contains "pixels" or picture elements covering a ground area; computerized equipment processes the tapes and plots each pixel, line be line to produce the basic image. Image can be further processed to correct sensor errors, to heighten contrast for feature emphasis or to enhance the end product in other ways. Key factor in conversion of digital data to visual form is precision of processing equipment. Jet Propulsion Laboratory prepared a digital mosaic that was plotted and enhanced by Optronics International, Inc. by use of the company's C-4300 Colorwrite, a high precision, high speed system which manipulates and analyzes digital data and presents it in visual form on film. Optronics manufactures a complete family of image enhancement processing systems to meet all users' needs. Enhanced imagery is useful to geologists, hydrologists, land use planners, agricultural specialists geographers and others.

  5. Information Processing.

    ERIC Educational Resources Information Center

    Jennings, Carol Ann; McDonald, Sandy

    This publication contains instructional materials for teacher and student use for a course in information processing. The materials are written in terms of student performance using measurable objectives. The course includes 10 units. Each instructional unit contains some or all of the basic components of a unit of instruction: performance…

  6. Budgeting Process

    ERIC Educational Resources Information Center

    Hentschke, Guilbert C.; Shaughnessy, John

    1973-01-01

    Discusses steps three and four in a budgeting process that uses Program Evaluation and Review Techniques (PERT). Step three involves developing time estimates and scheduling each of the activities in the PERT chart. Step four involves responsibility identification and coordination. (Author/JF)

  7. Image Processing

    DTIC Science & Technology

    1999-03-01

    blurs the processed image. Blurring is the primary limitation of low-pass filtering. Figure (10) shows a photo of the famous Taj -Hahal, one of the...Original Histo(p"am FILENAME.APP=41 06FG 1 O.PSD APPLICATION: ADOBE PHOTOSHOP VERSION 4.0 Figure (10) Photo ofTaj- Mahal with arbitrarily noise

  8. SEPARATION PROCESS

    DOEpatents

    Stoughton, R.W.

    1961-10-24

    A process for separating tetravalent plutonium from aqueous solutions and from niobium and zirconium by precipitation on lanthanum oxalate is described. The oxalate ions of the precipitate may be decomposed by heating in the presence of an oxidizing agent, forming a plutonium compound readily soluble in acid. (AEC)

  9. Fragmentation Processes

    NASA Astrophysics Data System (ADS)

    Whelan, Colm T.

    2012-12-01

    Preface; 1. Direct and resonant double-photoionization: from atoms to solids L. Avaldi and G. Stefani; 2. The application of propagation exterior complex scaling to atomic collisions P. L. Bartlett and A. T. Stelbovics; 3. Fragmentation of molecular-ion beams in intense ultra-short laser pulses I. Ben-Itzhak; 4. Atoms with one and two active electrons in strong laser fields I. A. Ivanov and A. S. Kheifets; 5. Experimental aspects of ionization studies by positron and positronium impact G. Laricchia, D. A. Cooke, Á. Kövér and S. J. Brawley; 6. (e,2e) spectroscopy using fragmentation processes J. Lower, M. Yamazaki and M. Takahashi; 7. A coupled pseudostate approach to the calculation of ion-atom fragmentation processes M. McGovern, H. R. J. Walters and C. T. Whelan; 8. Electron Impact Ionization using (e,2e) coincidence techniques from threshold to intermediate energies A. J. Murray; 9. (e,2e) processes on atomic inner shells C. T. Whelan; 10. Spin resolved atomic (e,2e) processes J. Lower and C. T. Whelan; Index.

  10. Processing Determinism

    ERIC Educational Resources Information Center

    O'Grady, William

    2015-01-01

    I propose that the course of development in first and second language acquisition is shaped by two types of processing pressures--internal efficiency-related factors relevant to easing the burden on working memory and external input-related factors such as frequency of occurrence. In an attempt to document the role of internal factors, I consider…

  11. On Process.

    ERIC Educational Resources Information Center

    Waxler, Robert P.

    1987-01-01

    Claims that the product approach to business writing prescribes a way of operating similar to imitation and creates an illusion of a static world when, in reality, the business environment is constantly in flux. Argues that the process approach to writing instruction should be used in business communication classes. (JD)

  12. Restoration Process

    NASA Technical Reports Server (NTRS)

    1979-01-01

    In the accompanying photos, a laboratory technician is restoring the once-obliterated serial number of a revolver. The four-photo sequence shows the gradual progression from total invisibility to clear readability. The technician is using a new process developed in an applications engineering project conducted by NASA's Lewis Research Center in conjunction with Chicago State University. Serial numbers and other markings are frequently eliminated from metal objects to prevent tracing ownership of guns, motor vehicles, bicycles, cameras, appliances and jewelry. To restore obliterated numbers, crime laboratory investigators most often employ a chemical etching technique. It is effective, but it may cause metal corrosion and it requires extensive preparatory grinding and polishing. The NASA-Chicago State process is advantageous because it can be applied without variation to any kind of metal, it needs no preparatory work and number recovery can be accomplished without corrosive chemicals; the liquid used is water.

  13. Process development

    NASA Technical Reports Server (NTRS)

    Bickler, D. B.

    1985-01-01

    An overview is given of seven process development activities which were presented at this session. Pulsed excimer laser processing of photovoltaic cells was presented. A different pulsed excimer laser annealing was described using a 50 w laser. Diffusion barrier research focused on lowering the chemical reactivity of amorphous thin film on silicon. In another effort adherent and conductive films were successfully achieved. Other efforts were aimed at achieving a simultaneous front and back junction. Microwave enhanced plasma deposition experiments were performed. An updated version of the Solar Array Manufacturing Industry Costing Standards (SAMICS) was presented, along with a life cycle cost analysis of high efficiency cells. The last presentation was on the evaluation of the ethyl vinyl acetate encapsulating system.

  14. Fermentation process

    SciTech Connect

    Lutzen, N.W.

    1982-02-23

    Fermentation process consists essentially of fermenting a 10-45% w/w aqueous slurry of granular starch for the production of ethanol with an ethanol-producing microorganism in the presence of alpha-amylase and glucoamylase, the conduct of said fermentation being characterized by low levels of dextrin and fermentable sugars in solution in the fermentation broth throughout the fermentation, and thereafter recovering enzymes from the fermentation broth for use anew in fermentation of granular starch.

  15. Optical Processing.

    DTIC Science & Technology

    1986-06-01

    general applications with average performance and certain numer- ical applications with very high per- formance. MIMD computers Support general ...Optical Processing I% FINAL REPORT June 1986 Heriot-Watt University University of Dayton Research Institute Subcontract Order No. RI-43109 ONR Main...apart, or a decoupled geometry in which the bias beamlet array, generated by the HOEs, is imaged by an intermediate, longer focal-length, high N.A. lens

  16. Veggie Processing

    NASA Image and Video Library

    2017-02-15

    Charles Spern, at right, project manager on the Engineering Services Contract (ESC), and Glenn Washington, ESC quality assurance specialist, perform final inspections of the Veggie Series 1 plant experiment inside a laboratory in the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. The Series 1 experiment is being readied for flight aboard Orbital ATK's Cygnus module on its seventh (OA-7) Commercial Resupply Services mission to the International Space Station. The Veggie system is on the space station.

  17. Hydropyrolysis process

    DOEpatents

    Ullman, Alan Z.; Silverman, Jacob; Friedman, Joseph

    1986-01-01

    An improved process for producing a methane-enriched gas wherein a hydrogen-deficient carbonaceous material is treated with a hydrogen-containing pyrolysis gas at an elevated temperature and pressure to produce a product gas mixture including methane, carbon monoxide and hydrogen. The improvement comprises passing the product gas mixture sequentially through a water-gas shift reaction zone and a gas separation zone to provide separate gas streams of methane and of a recycle gas comprising hydrogen, carbon monoxide and methane for recycle to the process. A controlled amount of steam also is provided which when combined with the recycle gas provides a pyrolysis gas for treatment of additional hydrogen-deficient carbonaceous material. The amount of steam used and the conditions within the water-gas shift reaction zone and gas separation zone are controlled to obtain a steady-state composition of pyrolysis gas which will comprise hydrogen as the principal constituent and a minor amount of carbon monoxide, steam and methane so that no external source of hydrogen is needed to supply the hydrogen requirements of the process. In accordance with a particularly preferred embodiment, conditions are controlled such that there also is produced a significant quantity of benzene as a valuable coproduct.

  18. Ceramic Processing

    SciTech Connect

    EWSUK,KEVIN G.

    1999-11-24

    Ceramics represent a unique class of materials that are distinguished from common metals and plastics by their: (1) high hardness, stiffness, and good wear properties (i.e., abrasion resistance); (2) ability to withstand high temperatures (i.e., refractoriness); (3) chemical durability; and (4) electrical properties that allow them to be electrical insulators, semiconductors, or ionic conductors. Ceramics can be broken down into two general categories, traditional and advanced ceramics. Traditional ceramics include common household products such as clay pots, tiles, pipe, and bricks, porcelain china, sinks, and electrical insulators, and thermally insulating refractory bricks for ovens and fireplaces. Advanced ceramics, also referred to as ''high-tech'' ceramics, include products such as spark plug bodies, piston rings, catalyst supports, and water pump seals for automobiles, thermally insulating tiles for the space shuttle, sodium vapor lamp tubes in streetlights, and the capacitors, resistors, transducers, and varistors in the solid-state electronics we use daily. The major differences between traditional and advanced ceramics are in the processing tolerances and cost. Traditional ceramics are manufactured with inexpensive raw materials, are relatively tolerant of minor process deviations, and are relatively inexpensive. Advanced ceramics are typically made with more refined raw materials and processing to optimize a given property or combination of properties (e.g., mechanical, electrical, dielectric, optical, thermal, physical, and/or magnetic) for a given application. Advanced ceramics generally have improved performance and reliability over traditional ceramics, but are typically more expensive. Additionally, advanced ceramics are typically more sensitive to the chemical and physical defects present in the starting raw materials, or those that are introduced during manufacturing.

  19. Speech Processing.

    DTIC Science & Technology

    1983-05-01

    airborne environment. The SEU’s ability to remove narrowband types of noises automatically and in real-time by as much as forty (40) d& decibels would...cepstral process that can improve the signal-to-noise ratio of noisy communication channels as much as 12 to 14 decibels . An improvement of this amount in...and Forgie, C.A., 1959, "Results Obtained from a Vowel Recognition Computer Program", J. Acoust Soc. Am 31(11) 8. Vicens, P. 1969, "Aspects of

  20. RF processing

    NASA Astrophysics Data System (ADS)

    Burhans, R. W.

    1982-06-01

    The Loran-C radio frequency processing is discussed. A diagram which generally illustrates the automatic gain control is presented. The augmented differentiator for pulse envelopes adapts conventional communications receiver with wideband AM capability to detect pulse signals such as Loran-C. The circuit enhances reception for surveillance and observation of HF over-the-horizon radar signals or others where time difference estimates between pulse returns are of interest. The high resolution VLF spectrum which receives weak VLF signals by using an HP 3581A wave analyzer detecting signals with a very narrow bandwidth of only 3 Hz is also presented.

  1. Nonequilibrium processes.

    PubMed

    Polanyi, J C

    1971-08-01

    Nonequilibrium phenomena have been studied for over half a century, particularly as a means to understanding the mechanism of energy transfer. Application of the insights and techniques of molecular physics to chemistry has resulted in a view of chemistry as constituting an aspect of the study of strong collisions, and chemical reaction as a special type of energy transfer. Increasing use has been made in experimental work of nonequilibrium environments for the study of chemical processes. The nature and purpose of such experiments are reviewed here, very briefly, and an attempt is made to point to areas that appear ripe for development over the coming decade.

  2. Veggie Processing

    NASA Image and Video Library

    2017-02-15

    Charles Spern, at right, project manager on the Engineering Services Contract (ESC), and Glenn Washington, ESC quality assurance specialist, perform final inspections of the Veggie Series 1 plant experiment inside a laboratory in the Space Station Processing Facility at NASA's Kennedy Space Center in Florida. At far left is Dena Richmond, ESC configuration management. The Series 1 experiment is being readied for flight aboard Orbital ATK's Cygnus module on its seventh (OA-7) Commercial Resupply Services mission to the International Space Station. The Veggie system is on the space station.

  3. Signal processing

    NASA Astrophysics Data System (ADS)

    Norman, David M.

    The application of signal processing technology to conventional weapons systems can lower operator workloads and enhance kill probabilities, while automating wide-area surveillance, target search and classification, target tracking, and aimpoint selection. Immediate opportunities exist for automatic target cueing in underwater and over-the-horizon targeting, as well as for airborne multiple-target fire control. By embedding the transit/receive electronics into conformal aircraft sensor arrays, a 'smart' skin can be created. Electronically scanned phased arrays can be used to yield accurate azimuthal and elevation positions while nullifying EW threats. Attention is given to major development thrusts in algorithm design.

  4. Signal Processing

    DTIC Science & Technology

    1989-03-01

    ORGANIZATION Univ of Minnesota (f*fto U. S. Army Research Office 6c. ADDRESS (City, State, and ZIP Code) 7b. ADDRESS (Wiy Stat, and ZIP Code...Minneapolis, MN 55455 P. 0. Box 12211 Research Triangle Park, NC 27709-2211 Sa. NAME Of FUNDING ISPONSORING Sb. OFFICE SYMBOL 9. PROCUREMENT INSTRUMENT...PROJECT ITASK jWORK UNIT Research Triangle Park, NC 27709-2211 EMNTO.I NO NO CESOIO 11. TITLE (Incudt Security Classifiratio") Signal Processing of, he auth

  5. Optical processing

    NASA Astrophysics Data System (ADS)

    Gustafson, S. C.

    1985-12-01

    The technical contributions were as follows: (1) Optical parallel 2-D neighborhood processor and optical processor assessment technique; (2) High accuracy with moderately accurate components and optical fredkin gate architectures; (3) Integrated optical threshold computing, pipelined polynomial processor, and all optical analog/digital converter; (4) Adaptive optical associative memory model with attention; (5) Effectiveness of parallelism and connectivity in optical computers; (6) Optical systolic array processing using an integrated acoustooptic module; (7) Optical threshold elements and networks, holographic threshold processors, adaptive matched spatial filtering, and coherence theory in optical computing; (8) Time-varying optical processing for sub-pixel targets, optical Kalman filtering, and adaptive matched filtering; (9) Optical degrees of freedom, ultra short optical pulses, number representations, content-addressable-memory processors, and integrated optical Givens rotation devices; (10) Optical J-K flip flop analysis and interfacing for optical computers; (11) Matrix multiplication algorithms and limits of incoherent optical computers; (12) Architecture for machine vision with sensor fusion, pattern recognition functions, and neural net implementations; (13) Optical computing algorithms, architectures, and components; and (14) Dynamic optical interconnections, advantages and architectures.

  6. Lithospheric processes

    SciTech Connect

    Baldridge, W.S.; Wohletz, K.; Fehler, M.C.

    1997-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The main objective was to improve understanding of the origin and evolution of the Earth`s lithosphere by studying selected processes, such as deformation and magmatic intrusion during crustal extension, formation and extraction of mantle melts, fluid transport of heat and mass, and surface processes that respond to deep-seated events. Additional objectives were to promote and develop innovative techniques and to support relevant educational endeavors. Seismic studies suggest that underplating of crust by mantle melts is an important crustal-growth mechanism, that low-angle faults can be seismogenic, and that shear deformation creates mantle anisotropy near plate boundaries. Results of geochemical work determined that magmas from oceanic intraplate islands are derived from a uniform depth in the upper mantle, whereas melts erupted at mid-ocean ridges are mixed from a range of depths. The authors have determined the extent and style of fluid infiltration and trace-element distribution in natural magmatic systems, and, finally, investigated {sup 21}Ne as a tool for dating of surficial materials.

  7. Large-scale Stratospheric Transport Processes

    NASA Technical Reports Server (NTRS)

    Plumb, R. Alan

    2003-01-01

    The PI has undertaken a theoretical analysis of the existence and nature of compact tracer-tracer relationships of the kind observed in the stratosphere, augmented with three-dimensional model simulations of stratospheric tracers (the latter being an extension of modeling work the group did during the SOLVE experiment). This work achieves a rigorous theoretical basis for the existence and shape of these relationships, as well as a quantitative theory of their width and evolution, in terms of the joint tracer-tracer PDF distribution. A paper on this work is almost complete and will soon be submitted to Rev. Geophys. We have analyzed lower stratospheric water in simulations with an isentropic-coordinate version of the MATCH transport model which we recently helped to develop. The three-dimensional structure of lower stratospheric water, in particular, attracted our attention: dry air is, below about 400K potential temperature, localized in the regions of the west Pacific and equatorial South America. We have been analyzing air trajectories to determine how air passes through the tropopause cold trap. This work is now being completed, and a paper will be submitted to Geophys. Res. Lett. before the end of summer. We are continuing to perform experiments with the 'MATCH' CTM, in both sigma- and entropy-coordinate forms. We earlier found (in collaboration with Dr Natalie Mahowald, and as part of an NSF-funded project) that switching to isentropic coordinates made a substantial improvement to the simulation of the age of stratospheric air. We are now running experiments with near-tropopause sources in both versions of the model, to see if and to what extent the simulation of stratosphere-troposphere transport is dependent on the model coordinate. Personnel Research is supervised by the PI, Prof. Alan Plumb. Mr William Heres conducts the tracer modeling work and performs other modeling tasks. Two graduate students, Ms Irene Lee and Mr Michael Ring, have been participating

  8. Physicochemical processes

    SciTech Connect

    Matsumoto, M.R.; Jensen, J.N.; McGinley, P.M.; Reed, B.E.

    1993-06-01

    A variety of waste water treatment processes are reported. Destruction of free and organically bound cyanides by alkaline hydrolysis in a pipeline reactor was studied. A bench-scale pilot system combining coagulation, sedimentation, and ultrafiltration to study treatment of animal wastewater was developed. A pilot limestone contactor was evaluated for its ability to treat a low pH, low alkalinity surface water supply for corrosion control, and as a conditioning step for flocculation. Experiments were conducted with a falling film reactor to determine the potential of freeze concentration to treat municipal wastewater for reuse. The effects of reductants and alkali on the sludge quantity from chromium(VI) wastes and the leachability and physical properties of solidified chromium sludge were investigated. Development and experience with a pilot-scale surfactant washing-flushing system to remove polychlorinated biphenyls (PCBs) from contaminated soils was reported.

  9. Lithospheric processes

    SciTech Connect

    Baldridge, W.

    2000-12-01

    The authors used geophysical, geochemical, and numerical modeling to study selected problems related to Earth's lithosphere. We interpreted seismic waves to better characterize the thickness and properties of the crust and lithosphere. In the southwestern US and Tien Shari, crust of high elevation is dynamically supported above buoyant mantle. In California, mineral fabric in the mantle correlate with regional strain history. Although plumes of buoyant mantle may explain surface deformation and magmatism, our geochemical work does not support this mechanism for Iberia. Generation and ascent of magmas remains puzzling. Our work in Hawaii constrains the residence of magma beneath Hualalai to be a few hundred to about 1000 years. In the crust, heat drives fluid and mass transport. Numerical modeling yielded robust and accurate predictions of these processes. This work is important fundamental science, and applies to mitigation of volcanic and earthquake hazards, Test Ban Treaties, nuclear waste storage, environmental remediation, and hydrothermal energy.

  10. Polymerization process

    SciTech Connect

    Kostelnik, R.J.

    1987-03-03

    An improved process is described for preparing a hydrocarbon fluid friction reducing composition comprising mixing two or more alpha-monoolefins having 2 to about 30 carbon atoms in a diluent or an organic solvent and copolymerizing the alpha-monoolefins in the presence of a catalyst. The catalyst is comprised of a reducible or reduced titanium halide and an organo metal catalyst activator consisting of, per each 100 total moles of activator, about 1 to 20 moles of at least one trialkylaluminium compound, each alkyl group of which has 1 to 10 carbon atoms and about 99 to 80 moles of at least one dialkylaluminium halide compound, each alkyl group of which has 1 to about 10 carbon atoms. The mole ratio of activator to catalyst in the reaction mixture is in the range of about 0.001:1 to 50:1.

  11. Oligomerization process

    DOEpatents

    Smith, L.A. Jr.; Hearn, D.; Jones, E.M. Jr.

    1991-03-26

    A liquid phase process is described for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled. 2 figures.

  12. Process Analyzer

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Under a NASA Small Business Innovation Research (SBIR) contract, Axiomatics Corporation developed a shunting Dielectric Sensor to determine the nutrient level and analyze plant nutrient solutions in the CELSS, NASA's space life support program. (CELSS is an experimental facility investigating closed-cycle plant growth and food processing for long duration manned missions.) The DiComp system incorporates a shunt electrode and is especially sensitive to changes in dielectric property changes in materials at measurements much lower than conventional sensors. The analyzer has exceptional capabilities for predicting composition of liquid streams or reactions. It measures concentrations and solids content up to 100 percent in applications like agricultural products, petrochemicals, food and beverages. The sensor is easily installed; maintenance is low, and it can be calibrated on line. The software automates data collection and analysis.

  13. Image Processing

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Electronic Imagery, Inc.'s ImageScale Plus software, developed through a Small Business Innovation Research (SBIR) contract with Kennedy Space Flight Center for use on space shuttle Orbiter in 1991, enables astronauts to conduct image processing, prepare electronic still camera images in orbit, display them and downlink images to ground based scientists for evaluation. Electronic Imagery, Inc.'s ImageCount, a spin-off product of ImageScale Plus, is used to count trees in Florida orange groves. Other applications include x-ray and MRI imagery, textile designs and special effects for movies. As of 1/28/98, company could not be located, therefore contact/product information is no longer valid.

  14. WELDING PROCESS

    DOEpatents

    Zambrow, J.; Hausner, H.

    1957-09-24

    A method of joining metal parts for the preparation of relatively long, thin fuel element cores of uranium or alloys thereof for nuclear reactors is described. The process includes the steps of cleaning the surfaces to be jointed, placing the sunfaces together, and providing between and in contact with them, a layer of a compound in finely divided form that is decomposable to metal by heat. The fuel element members are then heated at the contact zone and maintained under pressure during the heating to decompose the compound to metal and sinter the members and reduced metal together producing a weld. The preferred class of decomposable compounds are the metal hydrides such as uranium hydride, which release hydrogen thus providing a reducing atmosphere in the vicinity of the welding operation.

  15. Etherification process

    DOEpatents

    Smith, L.A. Jr.; Hearn, D.; Jones, E.M. Jr.

    1990-08-21

    A liquid phase process is described for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled. 2 figs.

  16. Retorting process

    SciTech Connect

    Reynolds, B.A.

    1984-06-19

    Fines in the overhead vapors from an oil shale retort process in which fresh shale together with hot recycle combusted shale from a combustor are fed to a retort and at least partly fluidized by a countercurrent stripping gas stream are handled by removing a portion of the fines in a vapor-solid separation optionally subjecting the portion of fines to additional retorting in a fines retort condensing the partially dedusted gas separating the condensate into a substantially finesfree liquid oil and a wet solids and recycling at least a portion of the wet solids to the retort, fines retort, and/or combustor whereby the liquid on the wet solids is recovered and/or burned and the wet solids are dried.

  17. Crystallization process

    DOEpatents

    Adler, Robert J.; Brown, William R.; Auyang, Lun; Liu, Yin-Chang; Cook, W. Jeffrey

    1986-01-01

    An improved crystallization process is disclosed for separating a crystallizable material and an excluded material which is at least partially excluded from the solid phase of the crystallizable material obtained upon freezing a liquid phase of the materials. The solid phase is more dense than the liquid phase, and it is separated therefrom by relative movement with the formation of a packed bed of solid phase. The packed bed is continuously formed adjacent its lower end and passed from the liquid phase into a countercurrent flow of backwash liquid. The packed bed extends through the level of the backwash liquid to provide a drained bed of solid phase adjacent its upper end which is melted by a condensing vapor.

  18. Oligomerization process

    DOEpatents

    Smith, Jr., Lawrence A.; hearn, Dennis; Jones, Jr., Edward M.

    1991-01-01

    A liquid phase process for oligomerization of C.sub.4 and C.sub.5 isoolefins or the etherification thereof with C.sub.1 to C.sub.6 alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300.degree. F. wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

  19. Etherification process

    DOEpatents

    Smith, Jr., Lawrence A.; Hearn, Dennis; Jones, Jr., Edward M.

    1990-01-01

    A liquid phase process for oligomerization of C.sub.4 and C.sub.5 isoolefins or the etherification thereof with C.sub.1 to C.sub.6 alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120.degree. to 300.degree. F. wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

  20. Dairy processing.

    PubMed

    Bailey, Kenneth W

    2003-07-01

    The United States dairy processing sector is dynamic and adaptive to new changes in the market place. Changes in consumer preferences and manufacturing technologies are resulting in new challenges to the processing sector. Consumers want a wider array of quality dairy products. Fluid processors are adapting to changing consumer demands for beverage products by introducing new flavors, providing ultrapasteurization, and using creative packaging. In addition, United States food manufacturers are requesting dairy processors to provide new dairy fractions such as MPC for new nutrition products. United States dairy policy is attempting to adapt to these changes. Federal order reform has resulted in new market-oriented signals for dairy farmers to produce what the market wants; namely, quality milk components. US dairy farmers, however, also wants to maintain programs such as the DPSP that have had the unfortunate consequence of spurring demand for protein imports (i.e., MPCs, casein, and caseinates) and also resulted in a disincentive to produce these new innovative protein products here in the United States. Surplus skim milk solids are now moving into US Government warehouses rather than into commercial markets. The future of the United States dairy industry will clearly be toward producing innovative products that the market wants. There is a strong market for dairy products not only here in the United States but also overseas, which will mean learning to compete on a global scale. The challenge is to modernize our United States milk pricing programs to provide dairy farmers and processors proper price signals while providing a minimum level of support to dairy farmers. The benefit of a greater orientation toward the market place will be stronger rates of growth for United States-produced dairy products.

  1. Publication process

    NASA Astrophysics Data System (ADS)

    Russell, C. T.; Reiff, P. H.

    Those who have contributed to the research literature are quite familiar with the workings of the publication process, even though they may not have seen it explicitly set down as is done in the accompanying flow chart. However, for the benefit of students, who are thought to read Eos, if only for the classified ads, and editors, who may have lost sight of the forest for the trees, we have requested that AGU publish this diagram. T h e flow chart is self-explanatory. We note that ΔtA,ΔtE, and ΔtR are time delays introduced by the author, the editor, and the referee. Since the editor gets to handle the paper twice each iteration (the number of which is counted by the index, I) he is responsible for a time delay of 2 ΔtE. The number NJ is journal dependent, ranging from 0 for some conference proceedings and forprofit journals, to 2 (or greater) for some AGU journals. (For example, this is our third submittal of this forum.) We would particularly like to thank G.C. Reid and S. Solomon and the many others who have had a hand in codifying this flow chart over the years and Eos editor, L.J. Lanzerotti, for his assistance in the further refinement of various details.

  2. Dynamic Processes

    NASA Astrophysics Data System (ADS)

    Klingshirn, C.

    . Phys. Lett. 92:211105, 2008). For this point, recall Figs. 6.16 and 6.33. Since the polarisation amplitude is gone in any case after the recombination process, there is an upper limit for T 2 given by T 2 ≤ 2 T1. The factor of two comes from the fact that T 2 describes the decay of an amplitude and T 1 the decay of a population, which is proportional to the amplitude squared. Sometimes T 2 is subdivided in a term due to recombination described by T 1 and another called 'pure dephasing' called T 2 ∗ with the relation 1 / T 2 = 1 / 2 T 1 + 1 / T2 ∗. The quantity T 2 ∗ can considerably exceed 2 T 1. In the part on relaxation processes that is on processes contributing to T 3, we give also examples for the capture of excitons into bound, localized, or deep states. For more details on dynamics in semiconductors in general see for example, the (text-) books [Klingshirn, Semiconductor Optics, 3rd edn. (Springer, Berlin, 2006); Haug and Koch, Quantum Theory of the Optical and Electronic Properties of Semiconductors, 4th edn. (World Scientific, Singapore, 2004); Haug and Jauho, Quantum Kinetics in Transport and Optics of Semiconductors, Springer Series in Solid State Sciences vol. 123 (Springer, Berlin, 1996); J. Shah, Ultrafast Spectroscopy of Semiconductors and of Semiconductor Nanostructures, Springer Series in Solid State Sciences vol. 115 (Springer, Berlin, 1996); Schafer and Wegener, Semiconductor Optics and Transport Phenomena (Springer, Berlin, 2002)]. We present selected data for free, bound and localized excitons, biexcitons and electron-hole pairs in an EHP and examples for bulk materials, epilayers, quantum wells, nano rods and nano crystals with the restriction that - to the knowledge of the author - data are not available for all these systems, density ranges and temperatures. Therefore, we subdivide the topic below only according to the three time constants T 2, T 3 and T 1.

  3. Condensed argon isentropic compression with ultrahigh magnetic field pressure: Experimental design. Post-shot report

    SciTech Connect

    Bykov, A.I.; Boriskov, G.V.; Dolotenko, M.I.

    1996-12-31

    This report continues the series of work devoted to experimental study of a high-dense condensed argon state. Remember that according to work of Kwon et. al., hexagonal close-packed structure is profitable in terms of energy rather than face-centered argon structure (stable with zero pressure). What is most interesting and intriguing here is the issue of possible argon metallization, when it is compressed up to the densities more than 9.17 g/cm{sup 3}. In the experiment of 1995 (the arrangement and data are described in a cited reference) the authors recorded appearance of conductivity in argon, which is non-conductive in the initial state, when it is compressed more than a factor of four. The peak value of argon specific conductivity recorded in this experiment did not exceed 10 (Ohm x cm){sup {minus}1}. This value of conductivity is characteristic of semiconductors, but not metals, which have 10{sup 4} (Ohm x cm){sup {minus}1}. At this stage of the work the main attention is paid to recording of argon conductive state and studying the possibilities of multiframed radiography of the sample in the compressed state.

  4. Unsteady specific work and isentropic efficiency of a radial turbine driven by pulsed detonations

    NASA Astrophysics Data System (ADS)

    Rouser, Kurt P.

    There has been longstanding government and industry interest in pressure-gain combustion for use in Brayton cycle based engines. Theoretically, pressure-gain combustion allows heat addition with reduced entropy loss. The pulsed detonation combustor (PDC) is a device that can provide such pressure-gain combustion and possibly replace typical steady deflagration combustors. The PDC is inherently unsteady, however, and comparisons with conventional steady deflagration combustors must be based upon time-integrated performance variables. In this study, the radial turbine of a Garrett automotive turbocharger was coupled directly to and driven, full admission, by a PDC in experiments fueled by hydrogen or ethylene. Data included pulsed cycle time histories of turbine inlet and exit temperature, pressure, velocity, mass flow, and enthalpy. The unsteady inlet flowfield showed momentary reverse flow, and thus unsteady accumulation and expulsion of mass and enthalpy within the device. The coupled turbine-driven compressor provided a time-resolved measure of turbine power. Peak power increased with PDC fill fraction, and duty cycle increased with PDC frequency. Cycle-averaged unsteady specific work increased with fill fraction and frequency. An unsteady turbine efficiency formulation is proposed, including heat transfer effects, enthalpy flux-weighted total pressure ratio, and ensemble averaging over multiple cycles. Turbine efficiency increased with frequency but was lower than the manufacturer reported conventional steady turbine efficiency.

  5. The isentropic light piston annular cascade facil ity at RAE Pyestock

    NASA Astrophysics Data System (ADS)

    Brooks, A. J.; Colbourne, D. E.; Wedlake, E. T.; Jones, T. V.; Oldfield, M. L. G.; Schultz, D. L.; Loftus, P. J.

    1985-09-01

    An accurate assessment of heat transfer rates to turbine vanes and blades is an important aspect of efficient cooling system design and component life prediction in gas turbines. Techniques have been developed at Oxford University which permit such measurements to be obtained in test rigs which provide short duration steady flow through a turbine cascade. The temperature ratio between the gas stream and the turbine correctly models that found in an engine environment. Reynolds number and Mach numaber can be varied over a wide range to match engine conditions. The design, construction and operation of a new facility at Royal Aircraft Establishment (RAE) Pyestock, incorporating these techniques, is described. Heat transfer and aerodynamic measurements have been made on airfoil surfaces and endwalls of a fully annular cascade of nozzle guide vanes. These results are discussed and compared with those obtained from the same profile in 2-D cascade tests, and with computed 3-D flow predictions.

  6. Isentropic wave propagation in a viscous fluid with uniform flow confined by a lined pipeline.

    PubMed

    Chen, Yong; Huang, Yiyong; Chen, Xiaoqian; Bai, Yuzhu

    2014-10-01

    The axisymmetric wave propagation in a viscous fluid with the presence of a uniform flow confined by a circular pipeline is investigated. Particular considerations are imposed on the features of the acoustic wave propagating in the liquid where the thermal conduction is neglected. The boundary constraints at the wall are reasonably discussed for both lined-walled and rigid-walled pipelines. Numerical comparisons of the phase velocity and wave attenuation among three different boundary configurations (rigid wall, steel-composed wall, and aluminum-composed wall) are presented. Meanwhile, the effects of the fluid viscosity and acoustic impedance are coherently analyzed. In the end, parametric analysis of the influence of the acoustic impedance is given in the case of a steel-composed pipeline.

  7. Direct Laser-Driven Quasi-Isentropic Compression on HEAVEN-I Laser

    NASA Astrophysics Data System (ADS)

    Zhang, Pin-Liang; Tang, Xiu-Zhang; Li, Ye-Jun; Wang, Zhao; Tian, Bao-Xian; Yin, Qian; Lu, Ze; Xiang, Yi-Huai; Gao, Zhi-Xing; Li, Jing; Hu, Feng-Ming; Gong, Zi-Zheng

    2015-07-01

    Not Available Supported by the National High-Technology Research and Development Program of China, and the Science and Technology on Reliability and Environmental Engineering Laboratory under Grant No KHZS20143010.

  8. High pressure, quasi-isentropic compression experiments on the Omega laser

    NASA Astrophysics Data System (ADS)

    Lorenz, K. T.; Edwards, M. J.; Jankowski, A. F.; Pollaine, S. M.; Smith, R. F.; Remington, B. A.

    2006-10-01

    The high energy density of pulsed lasers can be used to generate shockless loading in solids to high pressures and compressions but low temperatures. [J. Edwards, K.T. Lorenz, B.A. Remington, S. Pollaine, J. Colvin, D. Braun, B.F. Lasinski, D. Reisman, J.M. McNaney, J.A. Greenough, R.Wallace, H. Louis, D. Kalantar, Laser-driven plasma loader for shockless compression and acceleration of samples in the solid state, Phys. Rev. Lett. 92 (2004) 075002.] We have used the Omega laser to extend the capabilities of this technique to multi-Mbar pressures and compressions approaching a factor of 2 in aluminum foils. The energy from a 3.7 ns laser pulse is used to drive a strong shock through a 200 μm polystyrene disc. The disc material unloads from a high-pressure state and expands across a 300 μm vacuum gap where it stagnates against the sample to produce a smooth, monotonically increasing load with rise times from a few to ˜20 ns. Ramped compression waves having peak pressures of 14-200 GPa (0.14-2.0 Mbar) and peak compressions ρ/ ρ0 of 1.1-2.0 were generated in the aluminum samples using laser pulse energies of 400 J to 2 kJ. Wave profiles from a series of successively thicker targets loaded to 120 GPa show the evolution of the high-pressure compression wave within the sample. The initial loading in the sample is shockless, and develops into a shock at a depth of 20-25 μm. We compare these wave profiles with hydrodynamic simulations from which we extract material temperatures and plastic strain rates behind the compression wave. Limitations and future prospects for this new shockless loading technique are discussed.

  9. A Mixing Theory for the Interaction between Dissipative Flows and Nearly-Isentropic Streams

    DTIC Science & Technology

    1952-01-15

    increase in %^ increases the-b^se-pi?ess -;g^ire..{j0ecMöxisv % .and- k-JZ)^ fhess «ualitatis®- cmaA §@rätionsVare borne^ut . iby the.results .^f...iy bf extended’ to cases wixsre the.surf ace .heat iransfer rate- is hot sera. .. — n : .-’f-.u-’i »-W.’-S.W’/’ 1 70 _ _. ;r _\\_ The piTeseht t...8217 **£.-««’. ".*-*äÜ>tfä -m • 1 3£- f iiBSUkB**r f LOWS öV0N fQENHQPF _ BOGOQNÜFF=S©LÄRS^i SHOCK ^Ek,-_ 70 TB J© ɝV v:_- -f 1.2 1.1 1.0 A G 0

  10. A small helium liquifier which provides continuous cooling based on cycled isentropic expansion

    NASA Technical Reports Server (NTRS)

    Winter, C.; Gygax, S.; Myrtle, K.; Barton, R.

    1985-01-01

    This simple cryocooler provides a small reservoir of liquid helium at a stable temperature of 4.2K. It uses a novel adaptation of the Simon expansion cryocooler to provide continuous cooling. Operation is in a four stage cycle: (1) A closed vessel of helium under high pressure is cooled to 12K using a conventional Gifford-McMahon closed-cycle cryocooler. (2) The pressure is released adiabatically providing cooling to 4.2K. (3) Liquid helium is collected in a second, well insulated, vessel. (4) The first vessel is repressurized. The cycle time is 15-30 minutes. In this manner, a pool of liquid helium is continuously maintained in the second vessel, with a temperature stability of 0.03 degrees. The continuous cooling power available is 3mW. This design provides simplicity and reliability through the absence of any orifices or moving parts at cryogenic temperatures except for the conventional Gifford-McMahon cryocooler.

  11. Isentropic Compression of Argon and Krypton Using an MC1 Flux Compression Generator

    SciTech Connect

    Veeser, L.; Ekdahl, C.; Oona, H.; Rodriguez, P.; Schmitt, G.; Solem, J.; Younger, S.; Baker, S.; Hudson, C.; Lewis, W.; Marshall, B.; Turley, W.; Bykov, A.; Boriskov, G.; Dolotenko, M.; Egorov, N.; Kolokol'chikov, N.; Kozlov, M.; Kuropatkin, Y.; Volkov, A.

    1998-10-18

    LANL and VNIIEF are performing a set of joint experiments to explore the conductivity and possible metalization of argon and krypton compressed to up to five times normal solid density. The experiments use a magnetic field of several megagauss, generated by a Russian MC1 generator, to compress a metallic tube containing solidified argon or krypton. A probe in the center of the tube measures the electrical conductivity to the walls, and a 70-MeV betatron serves as an x-ray source for three radiographic measurements of the compression. Several of these experiments for argon compressed to around 4 to 5 times solid density indicate a conductivity in the range of 10 to 100 {Omega}{sup -1}cm{sup -1}, well below that of a metal. For krypton preliminary results show a conductivity of order 1000 or more, indicating likely metalization of the compressed sample.

  12. Deceleration of a supersonic flow behind a curved shock wave with isentropic precompression

    NASA Technical Reports Server (NTRS)

    Dulov, V. G.; Shchepanovskiy, V. A.

    1985-01-01

    Three-dimensional supersonic flows of an ideal fluid in the neighborhood of bodies formed by being cut out along the streamlines of an axisymmetric flow are investigated. The flow consists of a region of isoentropic compression and a region of vortex flow. An exact solution with variable entropy is used to describe the flow in the vortex region. In the continuous flow region an approximate solution is constructed by expanding the solution in a series in a small parameter. The effect of the shape of the excision and the vorticity of the flow on compression of the jet and and the total pressure loss coefficient is studied.

  13. Relationships Between Vertical Motion on Isentropic Surfaces from 3-Hr Rawinsonde Data and Radar Echoes.

    DTIC Science & Technology

    cm/s in a horizontal distance of 300 km. The rate of change of vertical motion is demonstrated to be as large as 8 cm/s/h from data taken at 3-h...intervals while data taken at 12-h intervals the same day displayed a maximum rate of change of 2 cm/s/h. Radar observations confirmed that the intensity

  14. High pressure, quasi-isentropic compression experiments on the Omega laser

    SciTech Connect

    Lorenz, K; Edwards, M; Jankowski, A; Pollaine, S; Smith, R; Remington, B

    2006-05-26

    The high energy density of pulsed lasers can be used to generate shockless loading in solids to high pressures and compressions but low temperatures. We have used the Omega laser to extend the capabilities of this technique to multi-Mbar pressures and compressions approaching a factor of 2 in aluminum foils. The energy from a 3.7 ns laser pulse is used to drive a strong shock through a 200 {micro}m polystyrene disc. The disc material unloads from a high-pressure state and expands across a 300 {micro}m vacuum gap where it stagnates against the sample to produce a smooth, monotonically increasing load with rise times from a few to {approx} 20 ns. Ramped compression reasing waves having peak pressures of 14-200 GPa (0.14-2.0 Mbar) and peak compressions {rho}/{rho}{sub 0} of 1.1-2.0 were generated in the aluminum samples using laser pulse energies of 400 J to 2 kJ. Wave profiles from a series of successively thicker targets loaded to 120 GPa show the evolution of the high-pressure compression wave within the sample. The initial loading in the sample is shockless, and develops into a shock at a depth of 20-25 {micro}m. We compare these wave profiles with hydrodynamic simulations from which we extract material temperatures and plastic strain rates behind the compression wave. Limitations and future prospects for this new shockless loading technique are discussed.

  15. Assessing mesoscale material response under shock & isentropic compression via high-resolution line-imaging VISAR.

    SciTech Connect

    Hall, Clint Allen; Furnish, Michael David; Podsednik, Jason W.; Reinhart, William Dodd; Trott, Wayne Merle; Mason, Joshua

    2003-10-01

    Of special promise for providing dynamic mesoscale response data is the line-imaging VISAR, an instrument for providing spatially resolved velocity histories in dynamic experiments. We have prepared two line-imaging VISAR systems capable of spatial resolution in the 10-20 micron range, at the Z and STAR facilities. We have applied this instrument to selected experiments on a compressed gas gun, chosen to provide initial data for several problems of interest, including: (1) pore-collapse in copper (two variations: 70 micron diameter hole in single-crystal copper) and (2) response of a welded joint in dissimilar materials (Ta, Nb) to ramp loading relative to that of a compression joint. The instrument is capable of resolving details such as the volume and collapse history of a collapsing isolated pore.

  16. Unsteady Specific Work and Isentropic Efficiency of a Radial Turbine Driven by Pulsed Detonations

    DTIC Science & Technology

    2012-06-14

    rotating detonation combustor RDE = rotating detonation engine SDC = steady deflagration combustor SiC = silicon carbide TDLAS = tunable diode...region of interest. Therefore, silicon carbide ( SiC ) seed particles (1-2 μm in size) have been used for seeding combustion flow fields. SiC filaments...Appendix F includes preliminary GT28 radial turbine inlet and exit flowfield measurements using high-speed cameras and silicon - carbide seed particles

  17. On Exact Solutions of Rarefaction-Rarefaction Interactions in Compressible Isentropic Flow

    NASA Astrophysics Data System (ADS)

    Jenssen, Helge Kristian

    2016-12-01

    Consider the interaction of two centered rarefaction waves in one-dimensional, compressible gas flow with pressure function p(ρ )=a^2ρ ^γ with γ >1 . The classic hodograph approach of Riemann provides linear 2nd order equations for the time and space variables t, x as functions of the Riemann invariants r, s within the interaction region. It is well known that t(r, s) can be given explicitly in terms of the hypergeometric function. We present a direct calculation (based on works by Darboux and Martin) of this formula, and show how the same approach provides an explicit formula for x(r, s) in terms of Appell functions (two-variable hypergeometric functions). Motivated by the issue of vacuum and total variation estimates for 1-d Euler flows, we then use the explicit t-solution to monitor the density field and its spatial variation in interactions of two centered rarefaction waves. It is found that the variation is always non-monotone, and that there is an overall increase in density variation if and only if γ >3 . We show that infinite duration of the interaction is characterized by approach toward vacuum in the interaction region, and that this occurs if and only if the Riemann problem defined by the extreme initial states generates a vacuum. Finally, it is verified that the minimal density in such interactions decays at rate O(1)/t.

  18. Data Processing

    NASA Astrophysics Data System (ADS)

    Grangeat, P.

    A new area of biology has been opened up by nanoscale exploration of the living world. This has been made possible by technological progress, which has provided the tools needed to make devices that can measure things on such length and time scales. In a sense, this is a new window upon the living world, so rich and so diverse. Many of the investigative methods described in this book seek to obtain complementary physical, chemical, and biological data to understand the way it works and the way it is organised. At these length and time scales, only dedicated instrumentation could apprehend the relevant phenomena. There is no way for our senses to observe these things directly. One important field of application is molecular medicine, which aims to explain the mechanisms of life and disease by the presence and quantification of specific molecular entities. This involves combining information about genes, proteins, cells, and organs. This in turn requires the association of instruments for molecular diagnosis, either in vitro, e.g., the microarray or the lab-on-a-chip, or in vivo, e.g., probes for molecular biopsy, and tools for molecular imaging, used to localise molecular information in living organisms in a non-invasive way. These considerations concern both preclinical research for drug design and human medical applications. With the development of DNA and RNA chips [1], genomics has revolutionised investigative methods for cells and cell processes [2,3]. By sequencing the human genome, new ways have been found for understanding the fundamental mechanisms of life [4]. A revolution is currently under way with the analysis of the proteome [5-8], i.e., the complete set of proteins that can be found in some given biological medium, such as the blood plasma. The goal is to characterise certain diseases by recognisable signatures in the proteomic profile, as determined from a blood sample or a biopsy, for example [9-13]. What is at stake is the early detection of

  19. Information Processing - Administrative Data Processing

    NASA Astrophysics Data System (ADS)

    Bubenko, Janis

    A three semester, 60-credit course package in the topic of Administrative Data Processing (ADP), offered in 1966 at Stockholm University (SU) and the Royal Institute of Technology (KTH) is described. The package had an information systems engineering orientation. The first semester focused on datalogical topics, while the second semester focused on the infological topics. The third semester aimed to deepen the students’ knowledge in different parts of ADP and at writing a bachelor thesis. The concluding section of this paper discusses various aspects of the department’s first course effort. The course package led to a concretisation of our discipline and gave our discipline an identity. Our education seemed modern, “just in time”, and well adapted to practical needs. The course package formed the first concrete activity of a group of young teachers and researchers. In a forty-year perspective, these people have further developed the department and the topic to an internationally well-reputed body of knowledge and research. The department has produced more than thirty professors and more than one hundred doctoral degrees.

  20. Hydrothermal Processes

    NASA Astrophysics Data System (ADS)

    German, C. R.; von Damm, K. L.

    2003-12-01

    What is Hydrothermal Circulation?Hydrothermal circulation occurs when seawater percolates downward through fractured ocean crust along the volcanic mid-ocean ridge (MOR) system. The seawater is first heated and then undergoes chemical modification through reaction with the host rock as it continues downward, reaching maximum temperatures that can exceed 400 °C. At these temperatures the fluids become extremely buoyant and rise rapidly back to the seafloor where they are expelled into the overlying water column. Seafloor hydrothermal circulation plays a significant role in the cycling of energy and mass between the solid earth and the oceans; the first identification of submarine hydrothermal venting and their accompanying chemosynthetically based communities in the late 1970s remains one of the most exciting discoveries in modern science. The existence of some form of hydrothermal circulation had been predicted almost as soon as the significance of ridges themselves was first recognized, with the emergence of plate tectonic theory. Magma wells up from the Earth's interior along "spreading centers" or "MORs" to produce fresh ocean crust at a rate of ˜20 km3 yr-1, forming new seafloor at a rate of ˜3.3 km2 yr-1 (Parsons, 1981; White et al., 1992). The young oceanic lithosphere formed in this way cools as it moves away from the ridge crest. Although much of this cooling occurs by upward conduction of heat through the lithosphere, early heat-flow studies quickly established that a significant proportion of the total heat flux must also occur via some additional convective process (Figure 1), i.e., through circulation of cold seawater within the upper ocean crust (Anderson and Silbeck, 1981). (2K)Figure 1. Oceanic heat flow versus age of ocean crust. Data from the Pacific, Atlantic, and Indian oceans, averaged over 2 Ma intervals (circles) depart from the theoretical cooling curve (solid line) indicating convective cooling of young ocean crust by circulating seawater

  1. Electrotechnologies to process foods

    USDA-ARS?s Scientific Manuscript database

    Electrical energy is being used to process foods. In conventional food processing plants, electricity drives mechanical devices and controls the degree of process. In recent years, several processing technologies are being developed to process foods directly with electricity. Electrotechnologies use...

  2. Hydrocarbon Processing`s process design and optimization `96

    SciTech Connect

    1996-06-01

    This paper compiles information on hydrocarbon processes, describing the application, objective, economics, commercial installations, and licensor. Processes include: alkylation, ammonia, catalytic reformer, crude fractionator, crude unit, vacuum unit, dehydration, delayed coker, distillation, ethylene furnace, FCCU, polymerization, gas sweetening, hydrocracking, hydrogen, hydrotreating (naphtha, distillate, and resid desulfurization), natural gas processing, olefins, polyethylene terephthalate, refinery, styrene, sulfur recovery, and VCM furnace.

  3. Extensible packet processing architecture

    DOEpatents

    Robertson, Perry J.; Hamlet, Jason R.; Pierson, Lyndon G.; Olsberg, Ronald R.; Chun, Guy D.

    2013-08-20

    A technique for distributed packet processing includes sequentially passing packets associated with packet flows between a plurality of processing engines along a flow through data bus linking the plurality of processing engines in series. At least one packet within a given packet flow is marked by a given processing engine to signify by the given processing engine to the other processing engines that the given processing engine has claimed the given packet flow for processing. A processing function is applied to each of the packet flows within the processing engines and the processed packets are output on a time-shared, arbitered data bus coupled to the plurality of processing engines.

  4. Physicochemical treatment processes

    SciTech Connect

    Grasso, D.; Morico, K.; Kock, N.; Flood, K.; Armstrong, R. ); Walters, R. ); Ellis, G. ); Chin, Yuping )

    1990-06-01

    This article discussed work done and accomplishments made in various methods and processes for physicochemical wastewater treatment. Processes discussed include general, precipitation, coagulation/flocculation, sedimentation/flotation, filtration, adsorption, ion exchange, membrane processes, mass transfer processes, phtotlytic processes, and oxidation/reduction processes.

  5. Coal liquefaction process with enhanced process solvent

    DOEpatents

    Givens, Edwin N.; Kang, Dohee

    1984-01-01

    In an improved coal liquefaction process, including a critical solvent deashing stage, high value product recovery is improved and enhanced process-derived solvent is provided by recycling second separator underflow in the critical solvent deashing stage to the coal slurry mix, for inclusion in the process solvent pool.

  6. A Distributed Processing Approach to Word Processing/Data Processing.

    ERIC Educational Resources Information Center

    Adams, Robert D.; Magnuson, Jerry R.

    1980-01-01

    A word processing system developed at the University of Kansas is described. A cost-benefit analysis of the system v standard typewriter, mag-card, and other advanced word processing systems is developed. Intangible benefits such as worker satisfaction and reduced training and editing needs are discussed, and possible uses outlined. (MSE)

  7. SAR processing using SHARC signal processing systems

    NASA Astrophysics Data System (ADS)

    Huxtable, Barton D.; Jackson, Christopher R.; Skaron, Steve A.

    1998-09-01

    Synthetic aperture radar (SAR) is uniquely suited to help solve the Search and Rescue problem since it can be utilized either day or night and through both dense fog or thick cloud cover. Other papers in this session, and in this session in 1997, describe the various SAR image processing algorithms that are being developed and evaluated within the Search and Rescue Program. All of these approaches to using SAR data require substantial amounts of digital signal processing: for the SAR image formation, and possibly for the subsequent image processing. In recognition of the demanding processing that will be required for an operational Search and Rescue Data Processing System (SARDPS), NASA/Goddard Space Flight Center and NASA/Stennis Space Center are conducting a technology demonstration utilizing SHARC multi-chip modules from Boeing to perform SAR image formation processing.

  8. Desalination processes and performance

    SciTech Connect

    Summers, L. J.

    1995-06-01

    Different desalination processes are evaluated for feed, capacity, performance, energy requirements, and cost. These include distillation, reverse osmosis, or electrodialysis. Detailed information is given on distillation processes and membrane processes.

  9. Special parallel processing workshop

    SciTech Connect

    1994-12-01

    This report contains viewgraphs from the Special Parallel Processing Workshop. These viewgraphs deal with topics such as parallel processing performance, message passing, queue structure, and other basic concept detailing with parallel processing.

  10. Hyperspectral processing in graphical processing units

    NASA Astrophysics Data System (ADS)

    Winter, Michael E.; Winter, Edwin M.

    2011-06-01

    With the advent of the commercial 3D video card in the mid 1990s, we have seen an order of magnitude performance increase with each generation of new video cards. While these cards were designed primarily for visualization and video games, it became apparent after a short while that they could be used for scientific purposes. These Graphical Processing Units (GPUs) are rapidly being incorporated into data processing tasks usually reserved for general purpose computers. It has been found that many image processing problems scale well to modern GPU systems. We have implemented four popular hyperspectral processing algorithms (N-FINDR, linear unmixing, Principal Components, and the RX anomaly detection algorithm). These algorithms show an across the board speedup of at least a factor of 10, with some special cases showing extreme speedups of a hundred times or more.

  11. Thermochemical water decomposition processes

    NASA Technical Reports Server (NTRS)

    Chao, R. E.

    1974-01-01

    Thermochemical processes which lead to the production of hydrogen and oxygen from water without the consumption of any other material have a number of advantages when compared to other processes such as water electrolysis. It is possible to operate a sequence of chemical steps with net work requirements equal to zero at temperatures well below the temperature required for water dissociation in a single step. Various types of procedures are discussed, giving attention to halide processes, reverse Deacon processes, iron oxide and carbon oxide processes, and metal and alkali metal processes. Economical questions are also considered.

  12. Thermochemical water decomposition processes

    NASA Technical Reports Server (NTRS)

    Chao, R. E.

    1974-01-01

    Thermochemical processes which lead to the production of hydrogen and oxygen from water without the consumption of any other material have a number of advantages when compared to other processes such as water electrolysis. It is possible to operate a sequence of chemical steps with net work requirements equal to zero at temperatures well below the temperature required for water dissociation in a single step. Various types of procedures are discussed, giving attention to halide processes, reverse Deacon processes, iron oxide and carbon oxide processes, and metal and alkali metal processes. Economical questions are also considered.

  13. Digital image processing.

    PubMed

    Seeram, Euclid

    2004-01-01

    Digital image processing is now commonplace in radiology, nuclear medicine and sonography. This article outlines underlying principles and concepts of digital image processing. After completing this article, readers should be able to: List the limitations of film-based imaging. Identify major components of a digital imaging system. Describe the history and application areas of digital image processing. Discuss image representation and the fundamentals of digital image processing. Outline digital image processing techniques and processing operations used in selected imaging modalities. Explain the basic concepts and visualization tools used in 3-D and virtual reality imaging. Recognize medical imaging informatics as a new area of specialization for radiologic technologists.

  14. Acoustic signal processing toolbox for array processing

    NASA Astrophysics Data System (ADS)

    Pham, Tien; Whipps, Gene T.

    2003-08-01

    The US Army Research Laboratory (ARL) has developed an acoustic signal processing toolbox (ASPT) for acoustic sensor array processing. The intent of this document is to describe the toolbox and its uses. The ASPT is a GUI-based software that is developed and runs under MATLAB. The current version, ASPT 3.0, requires MATLAB 6.0 and above. ASPT contains a variety of narrowband (NB) and incoherent and coherent wideband (WB) direction-of-arrival (DOA) estimation and beamforming algorithms that have been researched and developed at ARL. Currently, ASPT contains 16 DOA and beamforming algorithms. It contains several different NB and WB versions of the MVDR, MUSIC and ESPRIT algorithms. In addition, there are a variety of pre-processing, simulation and analysis tools available in the toolbox. The user can perform simulation or real data analysis for all algorithms with user-defined signal model parameters and array geometries.

  15. GREENSCOPE: Sustainable Process Modeling

    EPA Science Inventory

    EPA researchers are responding to environmental problems by incorporating sustainability into process design and evaluation. EPA researchers are also developing a tool that allows users to assess modifications to existing and new chemical processes to determine whether changes in...

  16. Natural Language Processing.

    ERIC Educational Resources Information Center

    Chowdhury, Gobinda G.

    2003-01-01

    Discusses issues related to natural language processing, including theoretical developments; natural language understanding; tools and techniques; natural language text processing systems; abstracting; information extraction; information retrieval; interfaces; software; Internet, Web, and digital library applications; machine translation for…

  17. Test processing system (SEE)

    NASA Technical Reports Server (NTRS)

    Gaulene, P.

    1986-01-01

    The SEE data processing system, developed in 1985, manages and process test results. General information is provided on the SEE system: objectives, characteristics, basic principles, general organization, and operation. Full documentation is accessible by computer using the HELP SEE command.

  18. Process evaluation distributed system

    NASA Technical Reports Server (NTRS)

    Moffatt, Christopher L. (Inventor)

    2006-01-01

    The distributed system includes a database server, an administration module, a process evaluation module, and a data display module. The administration module is in communication with the database server for providing observation criteria information to the database server. The process evaluation module is in communication with the database server for obtaining the observation criteria information from the database server and collecting process data based on the observation criteria information. The process evaluation module utilizes a personal digital assistant (PDA). A data display module in communication with the database server, including a website for viewing collected process data in a desired metrics form, the data display module also for providing desired editing and modification of the collected process data. The connectivity established by the database server to the administration module, the process evaluation module, and the data display module, minimizes the requirement for manual input of the collected process data.

  19. News: Process intensification

    EPA Science Inventory

    Conservation of materials and energy is a major objective to the philosophy of sustainability. Where production processes can be intensified to assist these objectives, significant advances have been developed to assist conservation as well as cost. Process intensification (PI) h...

  20. Polyamines in tea processing.

    PubMed

    Palavan-Unsal, Narcin; Arisan, Elif Damla; Terzioglu, Salih

    2007-06-01

    The distribution of dietary polyamines, putrescine, spermidine and spermine, was determined during processing of Camellia sinensis. Black tea manufacture is carried by a series of processes on fresh tea leaves involving withering, rolling, fermentation, drying and sieving. The aim of this research was to determine the effect of tea processing on the polyamine content in relation with antioxidant enzymes, superoxide dismutase, lipid peroxidase and glutathione peroxidase. Before processing, the spermine content was much higher than the putrescine and spermidine content in green tea leaves. Spermine was significantly decreased during processing while the putrescine and spermine contents increased during withered and rolling and decreased in the following stages. The superoxide dismutase activity increased at the withering stage and declined during processing. The transcript level of the polyamine biosynthesis-responsible enzyme ornithine decarboxylase was reduced during each processing step. This study reveals the importance of protection of nutritional compounds that are essential for health during the manufacturing process.

  1. GREENSCOPE: Sustainable Process Modeling

    EPA Science Inventory

    EPA researchers are responding to environmental problems by incorporating sustainability into process design and evaluation. EPA researchers are also developing a tool that allows users to assess modifications to existing and new chemical processes to determine whether changes in...

  2. News: Process intensification

    EPA Science Inventory

    Conservation of materials and energy is a major objective to the philosophy of sustainability. Where production processes can be intensified to assist these objectives, significant advances have been developed to assist conservation as well as cost. Process intensification (PI) h...

  3. Spacelab Data Processing Facility

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The capabilities of the Spacelab Data Processing Facility (SPDPF) are highlighted. The capturing, quality monitoring, processing, accounting, and forwarding of vital Spacelab data to various user facilities around the world are described.

  4. Probabilistic Declarative Process Mining

    NASA Astrophysics Data System (ADS)

    Bellodi, Elena; Riguzzi, Fabrizio; Lamma, Evelina

    The management of business processes is receiving much attention, since it can support significant efficiency improvements in organizations. One of the most interesting problems is the representation of process models in a language that allows to perform reasoning on it.

  5. Natural Language Processing.

    ERIC Educational Resources Information Center

    Chowdhury, Gobinda G.

    2003-01-01

    Discusses issues related to natural language processing, including theoretical developments; natural language understanding; tools and techniques; natural language text processing systems; abstracting; information extraction; information retrieval; interfaces; software; Internet, Web, and digital library applications; machine translation for…

  6. Infrared processing of foods

    USDA-ARS?s Scientific Manuscript database

    Infrared (IR) processing of foods has been gaining popularity over conventional processing in several unit operations, including drying, peeling, baking, roasting, blanching, pasteurization, sterilization, disinfection, disinfestation, cooking, and popping . It has shown advantages over conventional...

  7. Materials processing in space

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The feasibility and possible advantages of processing materials in a nongravitational field are considered. Areas of investigation include biomedical applications, the processing of inorganic materials, and flight programs and funding.

  8. The requirements discovery process

    SciTech Connect

    Bahill, A.T.; Dean, F.F.

    1997-02-01

    Cost and schedule overruns are often caused by poor requirements that are produced by people who do not understand the requirement process. This paper provides a high-level overview of the requirements discovery process.

  9. Fuel gas conditioning process

    DOEpatents

    Lokhandwala, Kaaeid A.

    2000-01-01

    A process for conditioning natural gas containing C.sub.3+ hydrocarbons and/or acid gas, so that it can be used as combustion fuel to run gas-powered equipment, including compressors, in the gas field or the gas processing plant. Compared with prior art processes, the invention creates lesser quantities of low-pressure gas per unit volume of fuel gas produced. Optionally, the process can also produce an NGL product.

  10. MITRE Adaptive Processing Capability

    DTIC Science & Technology

    1994-06-01

    gathering, Funded Research and Development transfer, processing , and interpretation of Center (FFRDC) under the primary data are provided. A strong state-of...1988: Unisys Reston Technology Center, Reston, VA Dr. Bronez was a Member of the Technical Staff. He performed research on signal processing and... processing , mathematical research , and sensor array processing . He was Project Leader and Principal Investigator for projects in adaptive beamforming

  11. Digital image processing

    NASA Technical Reports Server (NTRS)

    Bernstein, R.; Ferneyhough, D. G., Jr.

    1975-01-01

    The Federal Systems Division of IBM has developed an image processing facility to experimentally process, view, and record digital image data. This facility has been used to support LANDSAT digital image processing investigations and advanced image processing research and development. A brief description of the facility is presented, some techniques that have been developed to correct the image data are discussed, and some results obtained by users of the facility are described.

  12. Metallurgical processing: A compilation

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The items in this compilation, all relating to metallurgical processing, are presented in two sections. The first section includes processes which are general in scope and applicable to a variety of metals or alloys. The second describes the processes that concern specific metals and their alloys.

  13. Processes for metal extraction

    NASA Technical Reports Server (NTRS)

    Bowersox, David F.

    1992-01-01

    This report describes the processing of plutonium at Los Alamos National Laboratory (LANL), and operation illustrating concepts that may be applicable to the processing of lunar materials. The toxic nature of plutonium requires a highly closed system for processing lunar surface materials.

  14. Handbook of Petroleum Processing

    NASA Astrophysics Data System (ADS)

    Jones, David S. J.; Pujado, Peter P.

    This handbook describes and discusses the features that make up the petroleum refining industry. It begins with a description of the crude oils and their nature, and continues with the saleable products from the refining processes, with a review of the environmental impact. There is a complete overview of the processes that make up the refinery with a brief history of those processes.

  15. Current Duplicating Processes

    ERIC Educational Resources Information Center

    Groneman, Nancy

    1978-01-01

    While business instructors are still teaching spirit and stencil duplicating processes, most businesses now use copiers or offset printing processes. The article discusses offset and copier skills needed by office workers, pointing out that the processes being taught should be compatible with those used in business. (MF)

  16. Semisolid Metal Processing Consortium

    SciTech Connect

    Apelian,Diran

    2002-01-10

    Mathematical modeling and simulations of semisolid filling processes remains a critical issue in understanding and optimizing the process. Semisolid slurries are non-Newtonian materials that exhibit complex rheological behavior. There the way these slurries flow in cavities is very different from the way liquid in classical casting fills cavities. Actually filling in semisolid processing is often counter intuitive

  17. The Constitutional Amendment Process

    ERIC Educational Resources Information Center

    Chism, Kahlil

    2005-01-01

    This article discusses the constitutional amendment process. Although the process is not described in great detail, Article V of the United States Constitution allows for and provides instruction on amending the Constitution. While the amendment process currently consists of six steps, the Constitution is nevertheless quite difficult to change.…

  18. How yogurt is processed

    USDA-ARS?s Scientific Manuscript database

    This month’s Processing column on the theme of “How Is It Processed?” focuses on yogurt. Yogurt is known for its health-promoting properties. This column will provide a brief overview of the history of yogurt and the current market. It will also unveil both traditional and modern yogurt processing t...

  19. Comprehension Processes in Reading.

    ERIC Educational Resources Information Center

    Balota, D. A., Ed.; And Others

    Focusing on the process of reading comprehension, this book contains chapters on some central topics relevant to understanding the processes associated with comprehending text. The articles and their authors are as follows: (1) "Comprehension Processes: Introduction" (K. Rayner); (2) "The Role of Meaning in Word Recognition"…

  20. The Natural Learning Process

    ERIC Educational Resources Information Center

    Criss, Ellen

    2008-01-01

    Teacher-educator and researcher Daniel L. Kohut suggests in "Musical Performance: Learning Theory and Pedagogy" that there are many problems that result from the way music teachers often teach. Most teachers focus on the process, not the goal. The Natural Learning Process that Kohut advocates is the same process that young children use when they…

  1. The Constitutional Amendment Process

    ERIC Educational Resources Information Center

    Chism, Kahlil

    2005-01-01

    This article discusses the constitutional amendment process. Although the process is not described in great detail, Article V of the United States Constitution allows for and provides instruction on amending the Constitution. While the amendment process currently consists of six steps, the Constitution is nevertheless quite difficult to change.…

  2. Image-Processing Educator

    NASA Technical Reports Server (NTRS)

    Gunther, F. J.

    1986-01-01

    Apple Image-Processing Educator (AIPE) explores ability of microcomputers to provide personalized computer-assisted instruction (CAI) in digital image processing of remotely sensed images. AIPE is "proof-of-concept" system, not polished production system. User-friendly prompts provide access to explanations of common features of digital image processing and of sample programs that implement these features.

  3. Change Processes in Organization.

    ERIC Educational Resources Information Center

    1998

    This document contains four papers from a symposium on change processes in organizations. "Mid-stream Corrections: Decisions Leaders Make during Organizational Change Processes" (David W. Frantz) analyzes three organizational leaders to determine whether and how they take corrective actions or adapt their decision-making processes when…

  4. Image processing in astronomy

    NASA Astrophysics Data System (ADS)

    Berry, Richard

    1994-04-01

    Today's personal computers are more powerful than the mainframes that processed images during the early days of space exploration. We have entered an age in which anyone can do image processing. Topics covering the following aspects of image processing are discussed: digital-imaging basics, image calibration, image analysis, scaling, spatial enhancements, and compositing.

  5. How tofu is processed

    USDA-ARS?s Scientific Manuscript database

    This month’s Processing column will continue the theme of “How Is It Processed?” The column will focus on tofu, which is sometimes called “the cheese of Asia.” It is a nutritious, protein-rich bean curd made by coagulating soy milk. There are many different types of tofu, and they are processed in a...

  6. Chemical Process Synthesis.

    ERIC Educational Resources Information Center

    Siirola, J. J.

    1982-01-01

    Process synthesis is the specification of chemical and physical operations and the selection and interconnection of equipment to implement these operations to effect desired chemical processing transformations. Optimization and evolutionary and systematic generation process synthesis approaches are described. (Author/SK)

  7. The Natural Learning Process

    ERIC Educational Resources Information Center

    Criss, Ellen

    2008-01-01

    Teacher-educator and researcher Daniel L. Kohut suggests in "Musical Performance: Learning Theory and Pedagogy" that there are many problems that result from the way music teachers often teach. Most teachers focus on the process, not the goal. The Natural Learning Process that Kohut advocates is the same process that young children use when they…

  8. Change Processes in Organization.

    ERIC Educational Resources Information Center

    1998

    This document contains four papers from a symposium on change processes in organizations. "Mid-stream Corrections: Decisions Leaders Make during Organizational Change Processes" (David W. Frantz) analyzes three organizational leaders to determine whether and how they take corrective actions or adapt their decision-making processes when…

  9. Teaching Process Design through Integrated Process Synthesis

    ERIC Educational Resources Information Center

    Metzger, Matthew J.; Glasser, Benjamin J.; Patel, Bilal; Hildebrandt, Diane; Glasser, David

    2012-01-01

    The design course is an integral part of chemical engineering education. A novel approach to the design course was recently introduced at the University of the Witwatersrand, Johannesburg, South Africa. The course aimed to introduce students to systematic tools and techniques for setting and evaluating performance targets for processes, as well as…

  10. Teaching Process Design through Integrated Process Synthesis

    ERIC Educational Resources Information Center

    Metzger, Matthew J.; Glasser, Benjamin J.; Patel, Bilal; Hildebrandt, Diane; Glasser, David

    2012-01-01

    The design course is an integral part of chemical engineering education. A novel approach to the design course was recently introduced at the University of the Witwatersrand, Johannesburg, South Africa. The course aimed to introduce students to systematic tools and techniques for setting and evaluating performance targets for processes, as well as…

  11. Statistical Process Control for KSC Processing

    NASA Technical Reports Server (NTRS)

    Ford, Roger G.; Delgado, Hector; Tilley, Randy

    1996-01-01

    The 1996 Summer Faculty Fellowship Program and Kennedy Space Center (KSC) served as the basis for a research effort into statistical process control for KSC processing. The effort entailed several tasks and goals. The first was to develop a customized statistical process control (SPC) course for the Safety and Mission Assurance Trends Analysis Group. The actual teaching of this course took place over several weeks. In addition, an Internet version of the same course complete with animation and video excerpts from the course when it was taught at KSC was developed. The application of SPC to shuttle processing took up the rest of the summer research project. This effort entailed the evaluation of SPC use at KSC, both present and potential, due to the change in roles for NASA and the Single Flight Operations Contractor (SFOC). Individual consulting on SPC use was accomplished as well as an evaluation of SPC software for KSC use in the future. A final accomplishment of the orientation of the author to NASA changes, terminology, data format, and new NASA task definitions will allow future consultation when the needs arise.

  12. Process mapping: A user-friendly tool for process improvement

    NASA Astrophysics Data System (ADS)

    Carson, M. L.; Levine, L. O.

    1993-09-01

    Process maps aid administrative process improvement efforts by documenting processes in a rigorous yet understandable way. Icons, graphics, and text support process documentation, analysis, and improvement.

  13. Biomass process handbook

    SciTech Connect

    Not Available

    1983-01-01

    Descriptions are given of 42 processes which use biomass to produce chemical products. Marketing and economic background, process description, flow sheets, costs, major equipment, and availability of technology are given for each of the 42 processes. Some of the chemicals discussed are: ethanol, ethylene, acetaldehyde, butanol, butadiene, acetone, citric acid, gluconates, itaconic acid, lactic acid, xanthan gum, sorbitol, starch polymers, fatty acids, fatty alcohols, glycerol, soap, azelaic acid, perlargonic acid, nylon-11, jojoba oil, furfural, furfural alcohol, tetrahydrofuran, cellulose polymers, products from pulping wastes, and methane. Processes include acid hydrolysis, enzymatic hydrolysis, fermentation, distillation, Purox process, and anaerobic digestion.

  14. An improved plating process

    NASA Technical Reports Server (NTRS)

    Askew, John C.

    1994-01-01

    An alternative to the immersion process for the electrodeposition of chromium from aqueous solutions on the inside diameter (ID) of long tubes is described. The Vessel Plating Process eliminates the need for deep processing tanks, large volumes of solutions, and associated safety and environmental concerns. Vessel Plating allows the process to be monitored and controlled by computer thus increasing reliability, flexibility and quality. Elimination of the trivalent chromium accumulation normally associated with ID plating is intrinsic to the Vessel Plating Process. The construction and operation of a prototype Vessel Plating Facility with emphasis on materials of construction, engineered and operational safety and a unique system for rinse water recovery are described.

  15. Containerless processing technology

    NASA Technical Reports Server (NTRS)

    Oran, W. A.

    1983-01-01

    A brief review of containerless processing activities sponsored by NASA's Microgravity Science Division is presented. Attention is given to ground based systems such as shot tower processing of molten materials, single axis levitation and flight processing concepts including BeO processing aboard the Space Shuttle, a medium temperature three-axis acoustic positioning system and a high temperature single axis acoustic positioning system. In the future, more sophisticated experiments will be conducted using improved measurement techniques which will quantitatively define the advantages of containerless processing, as well as improve the understanding of nuclear kinetics and of the thermophysical properties of materials at high temperatures.

  16. Evaluation of steelmaking processes

    SciTech Connect

    Fruehan, R.J.

    1994-01-01

    Objective of the AISI Direct Steelmaking Program is to develop a process for producing steel directly from ore and coal; the process should be less capital intensive, consume less energy, and have higher productivity. A task force was formed to examine available processes: trough, posthearth, IRSID, Electric Arc Furnace, energy optimizing furnace. It is concluded that there is insufficient incentive to replace a working BOF with any of these processes to refine hot metal; however, if new steelmaking capacity is required, IRSID and EOF should be considered. A fully continuous process should not be considered until direct ironmaking and continuous refining are perfected.

  17. Process-based costing.

    PubMed

    Lee, Robert H; Bott, Marjorie J; Forbes, Sarah; Redford, Linda; Swagerty, Daniel L; Taunton, Roma Lee

    2003-01-01

    Understanding how quality improvement affects costs is important. Unfortunately, low-cost, reliable ways of measuring direct costs are scarce. This article builds on the principles of process improvement to develop a costing strategy that meets both criteria. Process-based costing has 4 steps: developing a flowchart, estimating resource use, valuing resources, and calculating direct costs. To illustrate the technique, this article uses it to cost the care planning process in 3 long-term care facilities. We conclude that process-based costing is easy to implement; generates reliable, valid data; and allows nursing managers to assess the costs of new or modified processes.

  18. Silicon production process evaluations

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Chemical engineering analyses involving the preliminary process design of a plant (1,000 metric tons/year capacity) to produce silicon via the technology under consideration were accomplished. Major activities in the chemical engineering analyses included base case conditions, reaction chemistry, process flowsheet, material balance, energy balance, property data, equipment design, major equipment list, production labor and forward for economic analysis. The process design package provided detailed data for raw materials, utilities, major process equipment and production labor requirements necessary for polysilicon production in each process.

  19. Nonaqueous processing methods

    SciTech Connect

    Coops, M.S.; Bowersox, D.F.

    1984-09-01

    A high-temperature process utilizing molten salt extraction from molten metal alloys has been developed for purification of spent power reactor fuels. Experiments with laboratory-scale processing operations show that purification and throughput parameters comparable to the Barnwell Purex process can be achieved by pyrochemical processing in equipment one-tenth the size, with all wastes being discharged as stable metal alloys at greatly reduced volume and disposal cost. This basic technology can be developed for large-scale processing of spent reactor fuels. 13 references, 4 figures.

  20. Gas processing handbook

    SciTech Connect

    Not Available

    1982-04-01

    Brief details are given of processes including: BGC-Lurgi slagging gasification, COGAS, Exxon catalytic coal gasification, FW-Stoic 2-stage, GI two stage, HYGAS, Koppers-Totzek, Lurgi pressure gasification, Saarberg-Otto, Shell, Texaco, U-Gas, W-D.IGI, Wellman-Galusha, Westinghouse, and Winkler coal gasification processes; the Rectisol process; the Catacarb and the Benfield processes for removing CO/SUB/2, H/SUB/2s and COS from gases produced by the partial oxidation of coal; the selectamine DD, Selexol solvent, and Sulfinol gas cleaning processes; the sulphur-tolerant shift (SSK) process; and the Super-meth process for the production of high-Btu gas from synthesis gas.

  1. Future Steelmaking Processes

    SciTech Connect

    Prof. R. J. Fruehan

    2004-09-20

    There is an increasing demand for an ironmaking process with lower capital cost, energy consumption and emissions than a blast furnace. It is the hypothesis of the present work that an optimized combination of two reasonable proven technologies will greatly enhance the overall process. An example is a rotary hearth furnace (RHF) linked to a smelter (e.g., AISI, HIsmelt). The objective of this research is to select promising process combinations, develop energy, materials balance and productivity models for the individual processes, conduct a limited amount of basic research on the processes and evaluate the process combinations. Three process combinations were selected with input from the industrial partners. The energy-materials and productivity models for the RHF, smelter, submerged arc furnace and CIRCOFER were developed. Since utilization of volatiles in coal is critical for energy and CO{sub 2} emission reduction, basic research on this topic was also conducted. The process models developed are a major product developed in this research. These models can be used for process evaluation by the industry. The process combinations of an RHF-Smelter and a simplified CIRCOFER-Smelter appear to be promising. Energy consumption is reduced and productivity increased. Work on this project is continuing using funds from other sources.

  2. Processes and process development in Japan

    NASA Technical Reports Server (NTRS)

    Noda, T.

    1986-01-01

    The commercialization of solar power generation necessitates the development of low cost manufacturing method of silicon suitable for solar cells. The manufacturing methods of semiconductor grade silicon (SEG-Si) and the development of solar grade silicon (SOG-Si) in foreign countries was investigated. It was concluded that the most efficient method of developing such materials was the hydrogen reduction process of trichlorosilane (TCS), using a fluidized bed reactor. The low cost reduction of polysilicon requires cost reductions of raw materials, energy, labor, and capital. These conditions were carefully reviewed. The overall conclusion was that a development program should be based on the TCS-FBR process and that the experimental program should be conducted in test facilities capable of producing 10 tons of silicon granules per year.

  3. Rumor Processes on and Discrete Renewal Processes

    NASA Astrophysics Data System (ADS)

    Gallo, Sandro; Garcia, Nancy L.; Junior, Valdivino Vargas; Rodríguez, Pablo M.

    2014-05-01

    We study two rumor processes on , the dynamics of which are related to an SI epidemic model with long range transmission. Both models start with one spreader at site and ignorants at all the other sites of , but differ by the transmission mechanism. In one model, the spreaders transmit the information within a random distance on their right, and in the other the ignorants take the information from a spreader within a random distance on their left. We obtain the probability of survival, information on the distribution of the range of the rumor and limit theorems for the proportion of spreaders. The key step of our proofs is to show that, in each model, the position of the spreaders on can be related to a suitably chosen discrete renewal process.

  4. Universal Heliophysical Processes

    NASA Technical Reports Server (NTRS)

    Gopalswamy, Natchimuthuk

    2011-01-01

    The physical processes in the heliospace are a direct consequence of the Sun s mass and electromagnetic emissions. There has been enormous progress in studying these processes since the dawn of the space age half a century ago. The heliospace serves as a great laboratory to study numerous physical processes, using the vast array of ground and spacebased measurements of various physical quantities. The observational capabilities collectively form the Great Observatory to make scientific investigations not envisioned by individual instrument teams. The International Heliophysical Year (IHY) program has been promoting scientific investigations on the universality of physical processes such as shocks, particle acceleration, dynamo, magnetic reconnection, magnetic flux ropes, plasma-neutral matter interactions, turbulence, and several other topics. This chapter highlights scientific deliberations on these and related topics that took place during the IAGA session on "Universal Heliophysical Processes" in Sopron, Hungary. The session featured several invited and contributed papers that focused on observations, theory and modeling of the universal heliophysical processes.

  5. Pultrusion process characterization

    NASA Technical Reports Server (NTRS)

    Vaughan, James G.; Hackett, Robert M.

    1991-01-01

    Pultrusion is a process through which high-modulus, lightweight composite structural members such as beams, truss components, stiffeners, etc., are manufactured. The pultrusion process, though a well-developed processing art, lacks a fundamental scientific understanding. The objective here was to determine, both experimentally and analytically, the process parameters most important in characterizing and optimizing the pultrusion of uniaxial fibers. The effects of process parameter interactions were experimentally examined as a function of the pultruded product properties. A numerical description based on these experimental results was developed. An analytical model of the pultrusion process was also developed. The objective of the modeling effort was the formulation of a two-dimensional heat transfer model and development of solutions for the governing differential equations using the finite element method.

  6. Badge Office Process Analysis

    SciTech Connect

    Haurykiewicz, John Paul; Dinehart, Timothy Grant; Parker, Robert Young

    2016-05-12

    The purpose of this process analysis was to analyze the Badge Offices’ current processes from a systems perspective and consider ways of pursuing objectives set forth by SEC-PS, namely increased customer flow (throughput) and reduced customer wait times. Information for the analysis was gathered for the project primarily through Badge Office Subject Matter Experts (SMEs), and in-person observation of prevailing processes. Using the information gathered, a process simulation model was constructed to represent current operations and allow assessment of potential process changes relative to factors mentioned previously. The overall purpose of the analysis was to provide SEC-PS management with information and recommendations to serve as a basis for additional focused study and areas for potential process improvements in the future.

  7. Spitzer Telemetry Processing System

    NASA Technical Reports Server (NTRS)

    Stanboli, Alice; Martinez, Elmain M.; McAuley, James M.

    2013-01-01

    The Spitzer Telemetry Processing System (SirtfTlmProc) was designed to address objectives of JPL's Multi-mission Image Processing Lab (MIPL) in processing spacecraft telemetry and distributing the resulting data to the science community. To minimize costs and maximize operability, the software design focused on automated error recovery, performance, and information management. The system processes telemetry from the Spitzer spacecraft and delivers Level 0 products to the Spitzer Science Center. SirtfTlmProc is a unique system with automated error notification and recovery, with a real-time continuous service that can go quiescent after periods of inactivity. The software can process 2 GB of telemetry and deliver Level 0 science products to the end user in four hours. It provides analysis tools so the operator can manage the system and troubleshoot problems. It automates telemetry processing in order to reduce staffing costs.

  8. Silicon production process evaluations

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The chemical engineering analysis of the preliminary process design of a process for producing solar cell grade silicon from dichlorosilane is presented. A plant to produce 1,000 MT/yr of silicon is analyzed. Progress and status for the plant design are reported for the primary activities of base case conditions (60 percent), reaction chemistry (50 percent), process flow diagram (35 percent), energy balance (10 percent), property data (10 percent) and equipment design (5 percent).

  9. The process audit.

    PubMed

    Hammer, Michael

    2007-04-01

    Few executives question the idea that by redesigning business processes--work that runs from end to end across an enterprise--they can achieve extraordinary improvements in cost, quality, speed, profitability, and other key areas Yet in spite of their intentions and investments, many executives flounder, unsure about what exactly needs to be changed, by how much, and when. As a result, many organizations make little progress--if any at all--in their attempts to transform business processes. Michael Hammer has spent the past five years working with a group of leading companies to develop the Process and Enterprise Maturity Model (PEMM), a new framework that helps executives comprehend, formulate, and assess process-based transformation efforts. He has identified two distinct groups of characteristics that are needed for business processes to perform exceptionally well over a long period of time. Process enablers, which affect individual processes, determine how well a process is able to function. They are mutually interdependent--if any are missing, the others will be ineffective. However, enablers are not enough to develop high-performance processes; they only provide the potential to deliver high performance. A company must also possess or establish organizational capabilities that allow the business to offer a supportive environment. Together, the enablers and the capabilities provide an effective way for companies to plan and evaluate process-based transformations. PEMM is different from other frameworks, such as Capability Maturity Model Integration (CMMI), because it applies to all industries and all processes. The author describes how several companies--including Michelin, CSAA, Tetra Pak, Shell, Clorox, and Schneider National--have successfully used PEMM in various ways and at different stages to evaluate the progress of their process-based transformation efforts.

  10. Image Processing Research

    DTIC Science & Technology

    1976-09-30

    Processing Institute University of Southern California University Park Los Angeles, California 90007 Sponsored by Advanced Research Projects Agency...Image Processing Institute University of Southern California University Park Los Angeles, California 90007 Accession For "mis GRA&l DTIC... Park Los Angeles, California 90007 ’«.’J. He »-’OH r ircuHiTr CLASJIUCATION UNCLASSIFIED 2ö. chouc 3 NEPOH f TITLE IMAGE PROCESSING

  11. Materials processing in space

    SciTech Connect

    Oran, W.A.

    1982-11-01

    A brief overview of the current Materials Processing in Space Program is given, including a tentative schedule of flight experiments. Some recent results of processing materials (e.g., polymers and eutectic materials) in a microgravity environment are given, along with a discussion on additional proposed flight experiments. Ground-based results and the rationale for flight experimentation will be presented for other materials processes, including crystal growth.

  12. Fjords: Processes and products

    SciTech Connect

    Syvitski, J.P.M.; Burrell, D.C.; Skei, J.M.

    1987-01-01

    Fjords are a major feature of coasts and provide geologists and oceanographers with an excellent environment for studying and modeling coastal processes and products. This book brings together and integrates an enormous amount of information on fjords and provides the reader with a thorough, interdisciplinary account of current research with emphasis on sedimentary processes. The processes demonstrated in fjords are often relevant to the estuarine or open ocean environment.

  13. Multiphoton processes: conference proceedings

    SciTech Connect

    Lambropoulos, P.; Smith, S.J.

    1984-01-01

    The chapters of this volume represent the invited papers delivered at the conference. They are arranged according to thermatic proximity beginning with atoms and continuing with molecules and surfaces. Section headings include multiphoton processes in atoms, field fluctuations and collisions in multiphoton process, and multiphoton processes in molecules and surfaces. Abstracts of individual items from the conference were prepared separately for the data base. (GHT)

  14. TEP process flow diagram

    SciTech Connect

    Wilms, R Scott; Carlson, Bryan; Coons, James; Kubic, William

    2008-01-01

    This presentation describes the development of the proposed Process Flow Diagram (PFD) for the Tokamak Exhaust Processing System (TEP) of ITER. A brief review of design efforts leading up to the PFD is followed by a description of the hydrogen-like, air-like, and waterlike processes. Two new design values are described; the mostcommon and most-demanding design values. The proposed PFD is shown to meet specifications under the most-common and mostdemanding design values.

  15. Digital signal processing

    NASA Astrophysics Data System (ADS)

    Oppenheim, A. V.; Baggeroer, A. B.; Lim, J. S.; Musicus, B. R.; Mook, D. R.; Duckworth, G. L.; Bordley, T. E.; Curtis, S. R.; Deadrick, D. S.; Dove, W. P.

    1984-01-01

    Signal and image processing research projects are described. Topics include: (1) modeling underwater acoustic propagation; (2) image restoration; (3) signal reconstruction; (4) speech enhancement; (5) pitch detection; (6) spectral analysis; (7) speech synthesis; (8) speech enhancement; (9) autoregressive spectral estimation; (10) knowledge based array processing; (11) speech analysis; (12) estimating the degree of coronary stenosis with image processing; (13) automatic target detection; and (14) video conferencing.

  16. GPS Decision Analysis Process

    DTIC Science & Technology

    2005-06-23

    712 A/B: GPS Decision Analysis Process Revised title:___________________________________________________________________ Presented in (input and Bold...JUN 2005 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE GPS Decision Analysis Process 5a. CONTRACT NUMBER 5b. GRANT NUMBER...Prescribed by ANSI Std Z39-18 GPS Decision Analysis Process Nisha Shah The Boeing Company 73rd MORS Symposium US Military Academy – West Point 21-23

  17. Containerless processing technology analysis

    NASA Technical Reports Server (NTRS)

    Rush, J. E.

    1982-01-01

    Research on acoustic levitation, air-jet levitation, and heat transfer from molten samples is reported. The goal was to obtain a better understanding and improving the quality of containerless processing systems. These systems are applied to the processing of materials in situations in which contact with a container must be avoided, and have potential application in both ground based and orbiting laboratories. Containerless processing is reviewed. The development of glasses from materials which normally crystallize upon cooling, are studied.

  18. NASA Hazard Analysis Process

    NASA Technical Reports Server (NTRS)

    Deckert, George

    2010-01-01

    This viewgraph presentation reviews The NASA Hazard Analysis process. The contents include: 1) Significant Incidents and Close Calls in Human Spaceflight; 2) Subsystem Safety Engineering Through the Project Life Cycle; 3) The Risk Informed Design Process; 4) Types of NASA Hazard Analysis; 5) Preliminary Hazard Analysis (PHA); 6) Hazard Analysis Process; 7) Identify Hazardous Conditions; 8) Consider All Interfaces; 9) Work a Preliminary Hazard List; 10) NASA Generic Hazards List; and 11) Final Thoughts

  19. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Fletcher, James C. (Inventor); Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1992-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  20. Living olefin polymerization processes

    DOEpatents

    Schrock, R.R.; Baumann, R.

    1999-03-30

    Processes for the living polymerization of olefin monomers with terminal carbon-carbon double bonds are disclosed. The processes employ initiators that include a metal atom and a ligand having two group 15 atoms and a group 16 atom or three group 15 atoms. The ligand is bonded to the metal atom through two anionic or covalent bonds and a dative bond. The initiators are particularly stable under reaction conditions in the absence of olefin monomer. The processes provide polymers having low polydispersities, especially block copolymers having low polydispersities. It is an additional advantage of these processes that, during block copolymer synthesis, a relatively small amount of homopolymer is formed.

  1. Living olefin polymerization processes

    DOEpatents

    Schrock, Richard R.; Baumann, Robert

    1999-01-01

    Processes for the living polymerization of olefin monomers with terminal carbon-carbon double bonds are disclosed. The processes employ initiators that include a metal atom and a ligand having two group 15 atoms and a group 16 atom or three group 15 atoms. The ligand is bonded to the metal atom through two anionic or covalent bonds and a dative bond. The initiators are particularly stable under reaction conditions in the absence of olefin monomer. The processes provide polymers having low polydispersities, especially block copolymers having low polydispersities. It is an additional advantage of these processes that, during block copolymer synthesis, a relatively small amount of homopolymer is formed.

  2. Living olefin polymerization processes

    DOEpatents

    Schrock, Richard R.; Baumann, Robert

    2003-08-26

    Processes for the living polymerization of olefin monomers with terminal carbon-carbon double bonds are disclosed. The processes employ initiators that include a metal atom and a ligand having two group 15 atoms and a group 16 atom or three group 15 atoms. The ligand is bonded to the metal atom through two anionic or covalent bonds and a dative bond. The initiators are particularly stable under reaction conditions in the absence of olefin monomer. The processes provide polymers having low polydispersities, especially block copolymers having low polydispersities. It is an additional advantage of these processes that, during block copolymer synthesis, a relatively small amount of homopolymer is formed.

  3. Living olefin polymerization processes

    DOEpatents

    Schrock, Richard R.; Bauman, Robert

    2006-11-14

    Processes for the living polymerization of olefin monomers with terminal carbon-carbon double bonds are disclosed. The processes employ initiators that include a metal atom and a ligand having two group 15 atoms and a group 16 atom or three group 15 atoms. The ligand is bonded to the metal atom through two anionic or covalent bonds and a dative bond. The initiators are particularly stable under reaction conditions in the absence of olefin monomer. The processes provide polymers having low polydispersities, especially block copolymers having low polydispersities. It is an additional advantage of these processes that, during block copolymer synthesis, a relatively small amount of homopolymer is formed.

  4. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1993-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of the additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  5. Central waste processing system

    NASA Technical Reports Server (NTRS)

    Kester, F. L.

    1973-01-01

    A new concept for processing spacecraft type wastes has been evaluated. The feasibility of reacting various waste materials with steam at temperatures of 538 - 760 C in both a continuous and batch reactor with residence times from 3 to 60 seconds has been established. Essentially complete gasification is achieved. Product gases are primarily hydrogen, carbon dioxide, methane, and carbon monoxide. Water soluble synthetic wastes are readily processed in a continuous tubular reactor at concentrations up to 20 weight percent. The batch reactor is able to process wet and dry wastes at steam to waste weight ratios from 2 to 20. Feces, urine, and synthetic wastes have been successfully processed in the batch reactor.

  6. JSME scatterometer data processing

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A software system was developed which processes digitized scatterometer data from the 13.3 GHz, 1.6 GHz and 400 MHz scatterometer systems. In addition to this, the hardware capability has been developed to recover the raw analog radar signals and the aircraft parameters from an ADAS data stream in a digital format for processing by the software package. Software for the preparation of data reports and chart presentation of scattering coefficients time histories has also been developed. This report documents the development of the software, describes key components of the processing system and presents examples of the processed data and procedure for software operation.

  7. RNA Processing and Export

    PubMed Central

    Hocine, Sami; Singer, Robert H.; Grünwald, David

    2010-01-01

    Messenger RNAs undergo 5' capping, splicing, 3'-end processing, and export before translation in the cytoplasm. It has become clear that these mRNA processing events are tightly coupled and have a profound effect on the fate of the resulting transcript. This processing is represented by modifications of the pre-mRNA and loading of various protein factors. The sum of protein factors that stay with the mRNA as a result of processing is modified over the life of the transcript, conferring significant regulation to its expression. PMID:20961978

  8. Powder towpreg process development

    NASA Technical Reports Server (NTRS)

    Baucom, Robert M.; Marchello, Joseph M.

    1991-01-01

    The process for dry powder impregnation of carbon fiber tows being developed at LaRC overcomes many of the difficulties associated with melt, solution, and slurry prepregging. In the process, fluidized powder is deposited on spread tow bundles and fused to the fibers by radiant heating. Impregnated tows have been produced for preform, weaving, and composite materials applications. Design and operating data correlations were developed for scale up of the process to commercial operation. Bench scale single tow experiments at tow speeds up to 50 cm/sec have demonstrated that the process can be controlled to produce weavable towpreg. Samples were woven and molded into preform material of good quality.

  9. Biased predecision processing.

    PubMed

    Brownstein, Aaron L

    2003-07-01

    Decision makers conduct biased predecision processing when they restructure their mental representation of the decision environment to favor one alternative before making their choice. The question of whether biased predecision processing occurs has been controversial since L. Festinger (1957) maintained that it does not occur. The author reviews relevant research in sections on theories of cognitive dissonance, decision conflict, choice certainty, action control, action phases, dominance structuring, differentiation and consolidation, constructive processing, motivated reasoning, and groupthink. Some studies did not find evidence of biased predecision processing, but many did. In the Discussion section, the moderators are summarized and used to assess the theories.

  10. Industrial Process Surveillance System

    DOEpatents

    Gross, Kenneth C.; Wegerich, Stephan W; Singer, Ralph M.; Mott, Jack E.

    2001-01-30

    A system and method for monitoring an industrial process and/or industrial data source. The system includes generating time varying data from industrial data sources, processing the data to obtain time correlation of the data, determining the range of data, determining learned states of normal operation and using these states to generate expected values, comparing the expected values to current actual values to identify a current state of the process closest to a learned, normal state; generating a set of modeled data, and processing the modeled data to identify a data pattern and generating an alarm upon detecting a deviation from normalcy.

  11. Lyophilization process design space.

    PubMed

    Patel, Sajal Manubhai; Pikal, Michael J

    2013-11-01

    The application of key elements of quality by design (QbD), such as risk assessment, process analytical technology, and design space, is discussed widely as it relates to freeze-drying process design and development. However, this commentary focuses on constructing the Design and Control Space, particularly for the primary drying step of the freeze-drying process. Also, practical applications and considerations of claiming a process Design Space under the QbD paradigm have been discussed. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.

  12. Mineral Processing Sector

    EPA Pesticide Factsheets

    Find environmental regulatory and compliance information for the nonmetallic mineral processing sector (NAICS 327), including NESHAPs for asbestos and hazardous waste, and wastewater permit information.

  13. Acoustic Signal Processing

    NASA Astrophysics Data System (ADS)

    Hartmann, William M.; Candy, James V.

    Signal processing refers to the acquisition, storage, display, and generation of signals - also to the extraction of information from signals and the re-encoding of information. As such, signal processing in some form is an essential element in the practice of all aspects of acoustics. Signal processing algorithms enable acousticians to separate signals from noise, to perform automatic speech recognition, or to compress information for more efficient storage or transmission. Signal processing concepts are the building blocks used to construct models of speech and hearing. Now, in the 21st century, all signal processing is effectively digital signal processing. Widespread access to high-speed processing, massive memory, and inexpensive software make signal processing procedures of enormous sophistication and power available to anyone who wants to use them. Because advanced signal processing is now accessible to everybody, there is a need for primers that introduce basic mathematical concepts that underlie the digital algorithms. The present handbook chapter is intended to serve such a purpose.

  14. Industrial process surveillance system

    DOEpatents

    Gross, Kenneth C.; Wegerich, Stephan W.; Singer, Ralph M.; Mott, Jack E.

    1998-01-01

    A system and method for monitoring an industrial process and/or industrial data source. The system includes generating time varying data from industrial data sources, processing the data to obtain time correlation of the data, determining the range of data, determining learned states of normal operation and using these states to generate expected values, comparing the expected values to current actual values to identify a current state of the process closest to a learned, normal state; generating a set of modeled data, and processing the modeled data to identify a data pattern and generating an alarm upon detecting a deviation from normalcy.

  15. Industrial process surveillance system

    DOEpatents

    Gross, K.C.; Wegerich, S.W.; Singer, R.M.; Mott, J.E.

    1998-06-09

    A system and method are disclosed for monitoring an industrial process and/or industrial data source. The system includes generating time varying data from industrial data sources, processing the data to obtain time correlation of the data, determining the range of data, determining learned states of normal operation and using these states to generate expected values, comparing the expected values to current actual values to identify a current state of the process closest to a learned, normal state; generating a set of modeled data, and processing the modeled data to identify a data pattern and generating an alarm upon detecting a deviation from normalcy. 96 figs.

  16. Future integrated design process

    NASA Technical Reports Server (NTRS)

    Meyer, D. D.

    1980-01-01

    The design process is one of the sources used to produce requirements for a computer system to integrate and manage product design data, program management information, and technical computation and engineering data management activities of the aerospace design process. Design activities were grouped chronologically and explored for activity type, activity interface, data quantity, and data flow. The work was based on analysis of the design process of several typical aerospace products, including both conventional and supersonic airplanes and a hydrofoil design. Activities examined included research, preliminary design, detail design, manufacturing interface, product verification, and product support. The design process was then described in an IPAD environment--the future.

  17. Ultrasonics in food processing.

    PubMed

    Chandrapala, Jayani; Oliver, Christine; Kentish, Sandra; Ashokkumar, Muthupandian

    2012-09-01

    In recent years, the physical and chemical effects of ultrasound in liquid and solid media have been extensively used in food processing applications. Harnessing the physical forces generated by ultrasound, in the absence and presence of cavitation, for specific food processing applications such as emulsification, filtration, tenderisation and functionality modification have been highlighted. While some applications, such as filtration and emulsification are "mature" industrial processes, other applications, such as functionality modification, are still in their early stages of development. However, various investigations discussed suggest that ultrasonic processing of food and dairy ingredients is a potential and viable technology that will be used by many food industries in the near future.

  18. Chemical process hazards analysis

    SciTech Connect

    1996-02-01

    The Office of Worker Health and Safety (EH-5) under the Assistant Secretary for the Environment, Safety and Health of the US Department (DOE) has published two handbooks for use by DOE contractors managing facilities and processes covered by the Occupational Safety and Health Administration (OSHA) Rule for Process Safety Management of Highly Hazardous Chemicals (29 CFR 1910.119), herein referred to as the PSM Rule. The PSM Rule contains an integrated set of chemical process safety management elements designed to prevent chemical releases that can lead to catastrophic fires, explosions, or toxic exposures. The purpose of the two handbooks, ``Process Safety Management for Highly Hazardous Chemicals`` and ``Chemical Process Hazards Analysis,`` is to facilitate implementation of the provisions of the PSM Rule within the DOE. The purpose of this handbook ``Chemical Process Hazards Analysis,`` is to facilitate, within the DOE, the performance of chemical process hazards analyses (PrHAs) as required under the PSM Rule. It provides basic information for the performance of PrHAs, and should not be considered a complete resource on PrHA methods. Likewise, to determine if a facility is covered by the PSM rule, the reader should refer to the handbook, ``Process Safety Management for Highly Hazardous Chemicals`` (DOE- HDBK-1101-96). Promulgation of the PSM Rule has heightened the awareness of chemical safety management issues within the DOE. This handbook is intended for use by DOE facilities and processes covered by the PSM rule to facilitate contractor implementation of the PrHA element of the PSM Rule. However, contractors whose facilities and processes not covered by the PSM Rule may also use this handbook as a basis for conducting process hazards analyses as part of their good management practices. This handbook explains the minimum requirements for PrHAs outlined in the PSM Rule. Nowhere have requirements been added beyond what is specifically required by the rule.

  19. EARSEC SAR processing system

    NASA Astrophysics Data System (ADS)

    Protheroe, Mark; Sloggett, David R.; Sieber, Alois J.

    1994-12-01

    Traditionally, the production of high quality Synthetic Aperture Radar imagery has been an area where a potential user would have to expend large amounts of money in either the bespoke development of a processing chain dedicated to his requirements or in the purchase of a dedicated hardware platform adapted using accelerator boards and enhanced memory management. Whichever option the user adopted there were limitations based on the desire for a realistic throughput in data load and time. The user had a choice, made early in the purchase, for either a system that adopted innovative algorithmic manipulation, to limit the processing time of the purchase of expensive hardware. The former limits the quality of the product, while the latter excludes the user from any visibility into the processing chain. Clearly there was a need for a SAR processing architecture that gave the user a choice into the methodology to be adopted for a particular processing sequence, allowing him to decide on either a quick (lower quality) product or a detailed slower (high quality) product, without having to change the algorithmic base of his processor or the hardware platform. The European Commission, through the Advanced Techniques unit of the Joint Research Centre (JRC) Institute for Remote Sensing at Ispra in Italy, realizing the limitations on current processing abilities, initiated its own program to build airborne SAR and Electro-Optical (EO) sensor systems. This program is called the European Airborne Remote Sensing Capabilities (EARSEC) program. This paper describes the processing system developed for the airborne SAR sensor system. The paper considers the requirements for the system and the design of the EARSEC Airborne SAR Processing System. It highlights the development of an open SAR processing architecture where users have full access to intermediate products that arise from each of the major processing stages. It also describes the main processing stages in the overall

  20. Development and Implementation of an Isentropic Potential Vorticity Algorithm for use at Air Force Global Weather Center

    DTIC Science & Technology

    1997-03-01

    conditions. vertical profiles of the global mean values are shown on the right (after Peixoto and Oort , 1992) ................ 33 vi Figure Description Page...scale vertical motions critical to cloud and precipitation forecasts, and an alternative method of locating the tropopause in cross-sectional analysis...Depiction and visualization of moisture advection have direct application to forecasting regions of likely cloud , contrail, and precipitation

  1. Food processing and allergenicity.

    PubMed

    Verhoeckx, Kitty C M; Vissers, Yvonne M; Baumert, Joseph L; Faludi, Roland; Feys, Marcel; Flanagan, Simon; Herouet-Guicheney, Corinne; Holzhauser, Thomas; Shimojo, Ryo; van der Bolt, Nieke; Wichers, Harry; Kimber, Ian

    2015-06-01

    Food processing can have many beneficial effects. However, processing may also alter the allergenic properties of food proteins. A wide variety of processing methods is available and their use depends largely on the food to be processed. In this review the impact of processing (heat and non-heat treatment) on the allergenic potential of proteins, and on the antigenic (IgG-binding) and allergenic (IgE-binding) properties of proteins has been considered. A variety of allergenic foods (peanuts, tree nuts, cows' milk, hens' eggs, soy, wheat and mustard) have been reviewed. The overall conclusion drawn is that processing does not completely abolish the allergenic potential of allergens. Currently, only fermentation and hydrolysis may have potential to reduce allergenicity to such an extent that symptoms will not be elicited, while other methods might be promising but need more data. Literature on the effect of processing on allergenic potential and the ability to induce sensitisation is scarce. This is an important issue since processing may impact on the ability of proteins to cause the acquisition of allergic sensitisation, and the subject should be a focus of future research. Also, there remains a need to develop robust and integrated methods for the risk assessment of food allergenicity. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Contaminated nickel scrap processing

    SciTech Connect

    Compere, A.L.; Griffith, W.L.; Hayden, H.W.; Johnson, J.S. Jr.; Wilson, D.F.

    1994-12-01

    The DOE will soon choose between treating contaminated nickel scrap as a legacy waste and developing high-volume nickel decontamination processes. In addition to reducing the volume of legacy wastes, a decontamination process could make 200,000 tons of this strategic metal available for domestic use. Contaminants in DOE nickel scrap include {sup 234}Th, {sup 234}Pa, {sup 137}Cs, {sup 239}Pu (trace), {sup 60}Co, U, {sup 99}Tc, and {sup 237}Np (trace). This report reviews several industrial-scale processes -- electrorefining, electrowinning, vapormetallurgy, and leaching -- used for the purification of nickel. Conventional nickel electrolysis processes are particularly attractive because they use side-stream purification of process solutions to improve the purity of nickel metal. Additionally, nickel purification by electrolysis is effective in a variety of electrolyte systems, including sulfate, chloride, and nitrate. Conventional electrorefining processes typically use a mixed electrolyte which includes sulfate, chloride, and borate. The use of an electrorefining or electrowinning system for scrap nickel recovery could be combined effectively with a variety of processes, including cementation, solvent extraction, ion exchange, complex-formation, and surface sorption, developed for uranium and transuranic purification. Selected processes were reviewed and evaluated for use in nickel side-stream purification. 80 refs.

  3. Process for preparing radiopharmaceuticals

    DOEpatents

    Barak, Morton; Winchell, Harry S.

    1977-01-04

    A process for the preparation of technetium-99m labeled pharmaceuticals is disclosed. The process comprises initially isolating technetium-99m pertechnetate by adsorption upon an adsorbent packing in a chromatographic column. The technetium-99m is then eluted from the packing with a biological compound to form a radiopharmaceutical.

  4. ELECTRONIC DATA PROCESSING EDUCATION.

    ERIC Educational Resources Information Center

    TONDOW, MURRAY

    EDUCATION HAS BEEN SLOW IN FULLY UTILIZING ELECTRONIC DATA PROCESSING EQUIPMENT (EDP). EDUCATOR CONFIDENCE IN THE EDP HAS GROWN, HOWEVER, AS A RESULT OF THE SUCCESS OF ELECTRONIC DATA PROCESSING IN SCIENCE, INDUSTRY, AND OTHER PROFESSIONS. THE DEVELOPMENT OF SOLID STATE TRANSISTORIZED COMPUTERS HAS MADE POWERFUL DESK-SIZE COMPUTERS A REALITY AND…

  5. HEPA filter dissolution process

    DOEpatents

    Brewer, K.N.; Murphy, J.A.

    1994-02-22

    A process is described for dissolution of spent high efficiency particulate air (HEPA) filters and then combining the complexed filter solution with other radioactive wastes prior to calcining the mixed and blended waste feed. The process is an alternate to a prior method of acid leaching the spent filters which is an inefficient method of treating spent HEPA filters for disposal. 4 figures.

  6. Hepa filter dissolution process

    DOEpatents

    Brewer, Ken N.; Murphy, James A.

    1994-01-01

    A process for dissolution of spent high efficiency particulate air (HEPA) filters and then combining the complexed filter solution with other radioactive wastes prior to calcining the mixed and blended waste feed. The process is an alternate to a prior method of acid leaching the spent filters which is an inefficient method of treating spent HEPA filters for disposal.

  7. Hyperspectral image processing methods

    USDA-ARS?s Scientific Manuscript database

    Hyperspectral image processing refers to the use of computer algorithms to extract, store and manipulate both spatial and spectral information contained in hyperspectral images across the visible and near-infrared portion of the electromagnetic spectrum. A typical hyperspectral image processing work...

  8. The Educational Process.

    ERIC Educational Resources Information Center

    Australian Coll. of Education, Carlton, Victoria.

    This book consists of 18 selected papers that focus on the broad topic of the educational process. All the papers were originally presented at the Fourteenth Annual Conference of the Australian College of Education, which was held in May 1973. Titles of the papers include "The Educational Process: The Raw Material,""Towards a…

  9. Building Successful Cleaning Processes.

    ERIC Educational Resources Information Center

    Walker, John P.

    2002-01-01

    Discusses how to build a successful cleaning process in order to most effectively maintain school facilities, explaining that the cleaning processes used plays a critical role in productivity. Focuses on: developing a standardized system; making sure that employees have the right tools for the work they perform; training employees; tracking and…

  10. Image processing mini manual

    NASA Technical Reports Server (NTRS)

    Matthews, Christine G.; Posenau, Mary-Anne; Leonard, Desiree M.; Avis, Elizabeth L.; Debure, Kelly R.; Stacy, Kathryn; Vonofenheim, Bill

    1992-01-01

    The intent is to provide an introduction to the image processing capabilities available at the Langley Research Center (LaRC) Central Scientific Computing Complex (CSCC). Various image processing software components are described. Information is given concerning the use of these components in the Data Visualization and Animation Laboratory at LaRC.

  11. Hybrid quantum information processing

    SciTech Connect

    Furusawa, Akira

    2014-12-04

    I will briefly explain the definition and advantage of hybrid quantum information processing, which is hybridization of qubit and continuous-variable technologies. The final goal would be realization of universal gate sets both for qubit and continuous-variable quantum information processing with the hybrid technologies. For that purpose, qubit teleportation with a continuousvariable teleporter is one of the most important ingredients.

  12. Building Successful Cleaning Processes.

    ERIC Educational Resources Information Center

    Walker, John P.

    2002-01-01

    Discusses how to build a successful cleaning process in order to most effectively maintain school facilities, explaining that the cleaning processes used plays a critical role in productivity. Focuses on: developing a standardized system; making sure that employees have the right tools for the work they perform; training employees; tracking and…

  13. Monitoring Process Effectiveness

    EPA Science Inventory

    Treatment of municipal sludges to produce biosolids which meet federal and/or state requirements for land application requires process monitoring. The goal of process monitoring is to produce biosolids of consistent and reliable quality. In its simplest form, for Class B treatme...

  14. METAL PLATING PROCESS

    DOEpatents

    Walker, D.E.; Noland, R.A.

    1958-08-12

    A process ts described for obtaining a closely bonded coating of steel or iron on uranium. The process consists of providing, between the steel and uramium. a layer of silver. amd then pressure rolling tbe assembly at about 600 deg C until a reduction of from l0 to 50% has been obtained.

  15. Patterns in neural processing

    NASA Astrophysics Data System (ADS)

    Engineer, Sunu

    2012-03-01

    In this paper we propose a model for neural processing that addresses both the evolutionary and functional aspects of neural systems that are observed in nature, from the simplest neural collections to dense large scale associations such as human brains. We propose both an architecture and a process in which these components interact to create the emergent behavior that we define as the 'mind'.

  16. Process Writing with Hawthorne.

    ERIC Educational Resources Information Center

    Edwards, Lita R.

    Teachers can use the process writing format for many assignments to teach and refine more skills than are often incorporated in older methods, and this is exemplified by a teaching unit comparing two short stories by Nathaniel Hawthorne. Peer conferences and peer editing in the revision stages, which are features of the process model, can lead to…

  17. On Cognizing Cognitive Processes.

    ERIC Educational Resources Information Center

    Rimoldi, H. J. A.

    In this report on cognitive processes, a discussion of the rationale and assumptions used by investigators explains the experimental procedures. To determine actual cognitive problem-solving processes, (rather than inferring them from results), subjects in these studies were presented with a problem and allowed to ask a sequence of questions which…

  18. Space processing applications bibliography

    NASA Technical Reports Server (NTRS)

    1978-01-01

    This special bibliography lists 724 articles, papers, and reports which discuss various aspects of the use of the space environment for materials science research or for commercial enterprise. The potentialities of space processing and the improved materials processes that are made possible by the unique aspects of the space environment are emphasized. References identified in April, 1978 are cited.

  19. Process Writing with Hawthorne.

    ERIC Educational Resources Information Center

    Edwards, Lita R.

    Teachers can use the process writing format for many assignments to teach and refine more skills than are often incorporated in older methods, and this is exemplified by a teaching unit comparing two short stories by Nathaniel Hawthorne. Peer conferences and peer editing in the revision stages, which are features of the process model, can lead to…

  20. Clean, Agile Processing Technology.

    DTIC Science & Technology

    1997-12-01

    Research ltr dtd 10 Jun 98 THIS PAGE IS UNCLASSIFIED FINAL REPORT CLEAN, AGILE PROCESSING TECHNOLOGY Contract # N00014-96-C-0139 PI: S. W . Sinton...Agile Processing Technology . T UNCLAS I N Sinton, S. W.IN S REQUIRED FOR (Explain needin detaiO E C This document is requested by the Canadian Department

  1. Polarization Radar Processing Technology

    DTIC Science & Technology

    1989-10-01

    Oi"C FILE ( J qII RADC-TR-89-144 In-House Report October 1989 AD-A215 242 POLARIZATION RADAR PROCESSING TECHNOLOGY Kenneth C. Stiefvater, Russell D...NO. NO. NO. ACCESSION NO. 62702F 4506 11 58 11. TITLE (Include Security Classification) POLARIZATION RADAR PROCESSING TECHNOLOGY 12. PERSONAL AUTHOR(S

  2. Kuhlthau's Information Search Process.

    ERIC Educational Resources Information Center

    Shannon, Donna

    2002-01-01

    Explains Kuhlthau's Information Search Process (ISP) model which is based on a constructivist view of learning and provides a framework for school library media specialists for the design of information services and instruction. Highlights include a shift from library skills to information skills; attitudes; process approach; and an interview with…

  3. Monitoring Process Effectiveness

    EPA Science Inventory

    Treatment of municipal sludges to produce biosolids which meet federal and/or state requirements for land application requires process monitoring. The goal of process monitoring is to produce biosolids of consistent and reliable quality. In its simplest form, for Class B treatme...

  4. Processing of plastics

    PubMed Central

    Spaak, Albert

    1975-01-01

    An overview is given of the processing of plastic materials from the handling of polymers in the pellet and powder form to manufacturing of a plastic fabricated product. Various types of equipment used and melt processing ranges of various polymer formulations to make the myriad of plastic products that are commercially available are discussed. PMID:1175556

  5. Sentences as Biological Processes.

    ERIC Educational Resources Information Center

    McNeil, David

    A study of the speech process was conducted. The process is described as one closely linked to the one involved in the problem of the serial order in behavior. It is pointed out that in the speech of young children the grammatical relations that are properties of elementary underlying sentences appear in the grammatical meanings. Six examples of…

  6. Electron-attachment processes

    NASA Astrophysics Data System (ADS)

    Christophorou, L. G.; McCorkle, D. L.; Christodoulides, A. A.

    Topics covered include: modes of production of negative ions, techniques for the study of electron attachment processes, dissociative electron attachment to ground state molecules, dissociative electron attachment to hot molecules (effects of temperature on dissociative electron attachment), molecular parent negative ions, and negative ions formed by ion pair processes and by collisions of molecules with ground state and Rydberg atoms.

  7. Integrated Optical Information Processing

    DTIC Science & Technology

    1988-08-01

    dimensional processing to be performed with inherently one-dimensional signal processing devices. This permits the monolithic or hybrid integration of...effective time delays; 5. Selective partial waveguide outcoupling of channelized light from an integrated optical chip; 6. Potential monolithic ... integrated optical chip; 6. Potential monolithic integration of optical waveguides with two-dimensional opto- electronic detector technology. The integrated

  8. Shell Higher Olefins Process.

    ERIC Educational Resources Information Center

    Lutz, E. F.

    1986-01-01

    Shows how olefin isomerization and the exotic olefin metathesis reaction can be harnessed in industrial processes. Indicates that the Shell Higher Olefins Process makes use of organometallic catalysts to manufacture alpha-olefins and internal carbon-11 through carbon-14 alkenes in a flexible fashion that can be adjusted to market needs. (JN)

  9. Microwave processing of ceramics

    SciTech Connect

    Katz, J.D.

    1993-01-01

    Recent work in the areas of microwave processing and joining of ceramics is briefly reviewed. Advantages and disadvantages of microwave processing as well as some of the current issues in the field are discussed. Current state and potential for future commercialization of this technology is also addressed.

  10. Microwave processing of ceramics

    SciTech Connect

    Katz, J.D.

    1993-04-01

    Recent work in the areas of microwave processing and joining of ceramics is briefly reviewed. Advantages and disadvantages of microwave processing as well as some of the current issues in the field are discussed. Current state and potential for future commercialization of this technology is also addressed.

  11. Interception processes during snowstorms

    Treesearch

    David H. Miller

    1964-01-01

    Four processes are identified as determining the initial interception of falling snow by forest during storms: delivery of snow particles from the airstream to the forest; true throughfall of particles to the forest floor; impaction and adhesion of particles to foliage and branches; and cohesion of particles into masses of snow. Delivery and impaction processes seem...

  12. Microsystem process networks

    DOEpatents

    Wegeng, Robert S.; TeGrotenhuis, Ward E.; Whyatt, Greg A.

    2007-09-18

    Various aspects and applications of microsystem process networks are described. The design of many types of Microsystems can be improved by ortho-cascading mass, heat, or other unit process operations. Microsystems having energetically efficient microchannel heat exchangers are also described. Detailed descriptions of numerous design features in microcomponent systems are also provided.

  13. Microsystem process networks

    DOEpatents

    Wegeng, Robert S.; TeGrotenhuis, Ward E.; Whyatt, Greg A.

    2006-10-24

    Various aspects and applications of microsystem process networks are described. The design of many types of microsystems can be improved by ortho-cascading mass, heat, or other unit process operations. Microsystems having exergetically efficient microchannel heat exchangers are also described. Detailed descriptions of numerous design features in microcomponent systems are also provided.

  14. Microsystem process networks

    DOEpatents

    Wegeng, Robert S [Richland, WA; TeGrotenhuis, Ward E [Kennewick, WA; Whyatt, Greg A [West Richland, WA

    2010-01-26

    Various aspects and applications or microsystem process networks are described. The design of many types of microsystems can be improved by ortho-cascading mass, heat, or other unit process operations. Microsystems having energetically efficient microchannel heat exchangers are also described. Detailed descriptions of numerous design features in microcomponent systems are also provided.

  15. Relational Processing Following Stroke

    ERIC Educational Resources Information Center

    Andrews, Glenda; Halford, Graeme S.; Shum, David; Maujean, Annick; Chappell, Mark; Birney, Damian

    2013-01-01

    The research examined relational processing following stroke. Stroke patients (14 with frontal, 30 with non-frontal lesions) and 41 matched controls completed four relational processing tasks: sentence comprehension, Latin square matrix completion, modified Dimensional Change Card Sorting, and n-back. Each task included items at two or three…

  16. HEPA filter dissolution process

    SciTech Connect

    Brewer, K.N.; Murphy, J.A.

    1992-12-31

    This invention is comprised of a process for dissolution of spent high efficiency particulate air (HEPA) filters and then combining the complexed filter solution with other radioactive wastes prior to calcining the mixed and blended waste feed. The process is an alternate to a prior method of acid leaching the spent filters which is an inefficient method of treating spent HEPA filters for disposal.

  17. How hummus is processed

    USDA-ARS?s Scientific Manuscript database

    This month’s column will continue the theme of “How Is It Processed?” The food to be discussed this month is hummus. Hummus is known for its healthfulness. This column will provide a brief overview of the history of hummus and the current market. It will also unveil hummus processing techniques....

  18. A Textbook Selection Process.

    ERIC Educational Resources Information Center

    Prosser, Daniel R.; Bondavalli, Bonnie J.

    In response to the problem facing college faculties of choosing textbooks that are both "readable" by students and adequate in content coverage, a text selection process has been developed that can be used with or without the aid of a reading specialist. The first step in the process, a preliminary check, examines each proposed text's publication…

  19. Basic Data Processing.

    ERIC Educational Resources Information Center

    Scalice, John J.

    This study guide in data processing is designed to make the subject accessible to the secondary student. It contains the following units: Historical Developments, Understanding the Computer, Careers in Data Processing, The Tabulating Card, Keypunching, Interpreting, Sorting, The 514 Reproducer, The 85 Collator, and The 402 Accounting Machine. The…

  20. Cognitive Processes and Achievement.

    ERIC Educational Resources Information Center

    Hunt, Dennis; Randhawa, Bikkar S.

    For a group of 165 fourth- and fifth-grade students, four achievement test scores were correlated with success on nine tests designed to measure three cognitive functions: sustained attention, successive processing, and simultaneous processing. This experiment was designed in accordance with Luria's model of the three functional units of the…

  1. Food-Processing Wastes.

    PubMed

    Frenkel, Val S; Cummings, Gregg A; Maillacheruvu, K Y; Tang, Walter Z

    2016-10-01

    Literature published in 2015 and early 2016 related to food processing wastes treatment for industrial applications are reviewed. This review is a subsection of the Treatment Systems section of the annual Water Environment Federation literature review and covers the following food processing industries and applications: general, meat and poultry, fruits and vegetables, dairy and beverage, and miscellaneous treatment of food wastes.

  2. Shell Higher Olefins Process.

    ERIC Educational Resources Information Center

    Lutz, E. F.

    1986-01-01

    Shows how olefin isomerization and the exotic olefin metathesis reaction can be harnessed in industrial processes. Indicates that the Shell Higher Olefins Process makes use of organometallic catalysts to manufacture alpha-olefins and internal carbon-11 through carbon-14 alkenes in a flexible fashion that can be adjusted to market needs. (JN)

  3. In Situ Processing.

    ERIC Educational Resources Information Center

    Edgar, T. F.; Schechter, R. S.

    1980-01-01

    Describes research on in situ processing to develop necessary theory and understanding of the underground process to facilitate commercialization of a wide range of mineral deposits. Goal is to produce laboratory and computer-based tools to allow site evaluation based on field and laboratory measurements of mineral and associated overburdens.…

  4. Streamlining the EIS Process

    ERIC Educational Resources Information Center

    Josephson, Julian

    1977-01-01

    A new publication service abstracts, indexes, and prepares microfiche of environmental impact statements (EIS). This new service is designed to streamline the EIS process by reducing the cost and time of preparation, by eliminating redundancy of similar statements, and by working with the government to standardize the preparation process. (MA)

  5. Mineral Processing Technology Roadmap

    SciTech Connect

    none,

    2000-09-01

    This document represents the roadmap for Processing Technology Research in the US Mining Industry. It was developed based on the results of a Processing Technology Roadmap Workshop sponsored by the National Mining Association in conjunction with the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Office of Industrial Technologies. The Workshop was held January 24 - 25, 2000.

  6. Associative list processing unit

    DOEpatents

    Hemmert, Karl Scott; Underwood, Keith D.

    2013-01-29

    An associative list processing unit and method comprising employing a plurality of prioritized cell blocks and permitting inserts to occur in a single clock cycle if all of the cell blocks are not full. Also, an associative list processing unit and method comprising employing a plurality of prioritized cell blocks and using a tree of prioritized multiplexers descending from the plurality of cell blocks.

  7. Process, Product, and Playmaking

    ERIC Educational Resources Information Center

    Fisher, Maisha T.; Purcell, Susie Spear; May, Rachel

    2009-01-01

    This article examines relationships among process, product, and playmaking in a southeastern playwriting and performance program for teen girls, Playmaking for Girls (PFG). The authors have chosen to focus on tensions between process and product. Such tensions are present in the challenges teachers experience when privileging student-centered…

  8. A Textbook Selection Process.

    ERIC Educational Resources Information Center

    Prosser, Daniel R.; Bondavalli, Bonnie J.

    In response to the problem facing college faculties of choosing textbooks that are both "readable" by students and adequate in content coverage, a text selection process has been developed that can be used with or without the aid of a reading specialist. The first step in the process, a preliminary check, examines each proposed text's publication…

  9. Processes in Reading Comprehension.

    ERIC Educational Resources Information Center

    Ransom, Grayce A.

    This examination of the processes in reading comprehension is divided into seven categories. "Theoretical Foundations" reviews some of the research conducted by Bruner, Piaget, and Bloom in the areas of cognition or comprehension processes of young children. "Development of a Spiraling Reading Curriculum" examines a spiraling taxonomy of reading…

  10. Relational Processing Following Stroke

    ERIC Educational Resources Information Center

    Andrews, Glenda; Halford, Graeme S.; Shum, David; Maujean, Annick; Chappell, Mark; Birney, Damian

    2013-01-01

    The research examined relational processing following stroke. Stroke patients (14 with frontal, 30 with non-frontal lesions) and 41 matched controls completed four relational processing tasks: sentence comprehension, Latin square matrix completion, modified Dimensional Change Card Sorting, and n-back. Each task included items at two or three…

  11. Silicon production process evaluations

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Chemical engineering analysis of the HSC process (Hemlock Semiconductor Corporation) for producing silicon from dichlorosilane in a 1,000 MT/yr plant was continued. Progress and status for the chemical engineering analysis of the HSC process are reported for the primary process design engineering activities: base case conditions (85%), reaction chemistry (85%), process flow diagram (60%), material balance (60%), energy balance (30%), property data (30%), equipment design (20%) and major equipment list (10%). Engineering design of the initial distillation column (D-01, stripper column) in the process was initiated. The function of the distillation column is to remove volatile gases (such as hydrogen and nitrogen) which are dissolved in liquid chlorosilanes. Initial specifications and results for the distillation column design are reported including the variation of tray requirements (equilibrium stages) with reflux ratio for the distillation.

  12. Economics of polysilicon processes

    NASA Technical Reports Server (NTRS)

    Yaws, C. L.; Li, K. Y.; Chou, S. M.

    1986-01-01

    Techniques are being developed to provide lower cost polysilicon material for solar cells. Existing technology which normally provides semiconductor industry polysilicon material is undergoing changes and also being used to provide polysilicon material for solar cells. Economics of new and existing technologies are presented for producing polysilicon. The economics are primarily based on the preliminary process design of a plant producing 1,000 metric tons/year of silicon. The polysilicon processes include: Siemen's process (hydrogen reduction of trichlorosilane); Union Carbide process (silane decomposition); and Hemlock Semiconductor process (hydrogen reduction of dichlorosilane). The economics include cost estimates of capital investment and product cost to produce polysilicon via the technology. Sensitivity analysis results are also presented to disclose the effect of major paramentes such as utilities, labor, raw materials and capital investment.

  13. Formed HIP Can Processing

    SciTech Connect

    Clarke, Kester Diederik

    2015-07-27

    The intent of this report is to document a procedure used at LANL for HIP bonding aluminum cladding to U-10Mo fuel foils using a formed HIP can for the Domestic Reactor Conversion program in the NNSA Office of Material, Management and Minimization, and provide some details that may not have been published elsewhere. The HIP process is based on the procedures that have been used to develop the formed HIP can process, including the baseline process developed at Idaho National Laboratory (INL). The HIP bonding cladding process development is summarized in the listed references. Further iterations with Babcock & Wilcox (B&W) to refine the process to meet production and facility requirements is expected.

  14. Spacelab Data Processing Facility

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The Spacelab Data Processing Facility (SDPF) processes, monitors, and accounts for the payload data from Spacelab and other Shuttle missions and forwards relevant data to various user facilities worldwide. The SLDPF is divided into the Spacelab Input Processing System (SIPS) and the Spacelab Output Processing System (SOPS). The SIPS division demultiplexes, synchronizes, time tags, quality checks, accounts for the data, and formats the data onto tapes. The SOPS division further edits, blocks, formats, and records the data on tape for shipment to users. User experiments must conform to the Spacelab's onboard High Rate Multiplexer (HRM) format for maximum process ability. Audio, analog, instrumentation, high density, experiment data, input/output data, quality control and accounting, and experimental channel tapes along with a variety of spacelab ancillary tapes are provided to the user by SLDPF.

  15. Materials processing in space

    NASA Technical Reports Server (NTRS)

    Waldron, R. D.; Criswell, D. R.

    1982-01-01

    Processing-refining of raw materials from extraterrestrial sources is detailed for a space materials handling facility. The discussion is constrained to those steps necessary to separate desired components from raw or altered input ores, semi-purified feedstocks, or process scrap and convert the material into elements, alloys, and consumables. The materials are regarded as originating from dead satellites and boosters, lunar materials, and asteroids. Strong attention will be given to recycling reagent substances to avoid the necessity of transporting replacements. It is assumed that since no aqueous processes exist on the moon, the distribution of minerals will be homogeneous. The processing-refining scenario will include hydrochemical, pyrochemical, electrochemical, and physical techniques selected for the output mass rate/unit plant mass ratio. Flow charts of the various materials processing operations which could be performed with lunar materials are provided, noting the necessity of delivering several alloying elements from the earth due to scarcities on the moon.

  16. Elemental sulfur recovery process

    DOEpatents

    Flytzani-Stephanopoulos, Maria; Hu, Zhicheng

    1993-01-01

    An improved catalytic reduction process for the direct recovery of elemental sulfur from various SO.sub.2 -containing industrial gas streams. The catalytic process provides combined high activity and selectivity for the reduction of SO.sub.2 to elemental sulfur product with carbon monoxide or other reducing gases. The reaction of sulfur dioxide and reducing gas takes place over certain catalyst formulations based on cerium oxide. The process is a single-stage, catalytic sulfur recovery process in conjunction with regenerators, such as those used in dry, regenerative flue gas desulfurization or other processes, involving direct reduction of the SO.sub.2 in the regenerator off gas stream to elemental sulfur in the presence of a catalyst.

  17. Elemental sulfur recovery process

    DOEpatents

    Flytzani-Stephanopoulos, M.; Zhicheng Hu.

    1993-09-07

    An improved catalytic reduction process for the direct recovery of elemental sulfur from various SO[sub 2]-containing industrial gas streams. The catalytic process provides combined high activity and selectivity for the reduction of SO[sub 2] to elemental sulfur product with carbon monoxide or other reducing gases. The reaction of sulfur dioxide and reducing gas takes place over certain catalyst formulations based on cerium oxide. The process is a single-stage, catalytic sulfur recovery process in conjunction with regenerators, such as those used in dry, regenerative flue gas desulfurization or other processes, involving direct reduction of the SO[sub 2] in the regenerator off gas stream to elemental sulfur in the presence of a catalyst. 4 figures.

  18. Optical signal processing

    NASA Technical Reports Server (NTRS)

    Casasent, D.

    1978-01-01

    The article discusses several optical configurations used for signal processing. Electronic-to-optical transducers are outlined, noting fixed window transducers and moving window acousto-optic transducers. Folded spectrum techniques are considered, with reference to wideband RF signal analysis, fetal electroencephalogram analysis, engine vibration analysis, signal buried in noise, and spatial filtering. Various methods for radar signal processing are described, such as phased-array antennas, the optical processing of phased-array data, pulsed Doppler and FM radar systems, a multichannel one-dimensional optical correlator, correlations with long coded waveforms, and Doppler signal processing. Means for noncoherent optical signal processing are noted, including an optical correlator for speech recognition and a noncoherent optical correlator.

  19. Business Process Management

    NASA Astrophysics Data System (ADS)

    Mendling, Jan

    The recent progress of Business Process Management (BPM) is reflected by the figures of the related industry. Wintergreen Research estimates that the international market for BPM-related software and services accounted for more than USD 1 billion in 2005 with a tendency towards rapid growth in the subsequent couple of years [457]. The relevance of business process modeling to general management initiatives has been previously studied in the 1990s [28]. Today, Gartner finds that organizations that had the best results in implementing business process management spent more than 40 percent of the total project time on discovery and construction of their initial process model [265]. As a consequence, Gartner considers Business Process Modeling to be among the Top 10 Strategic Technologies for 2008.

  20. EDITORIAL: Industrial Process Tomography

    NASA Astrophysics Data System (ADS)

    Anton Johansen, Geir; Wang, Mi

    2008-09-01

    There has been tremendous development within measurement science and technology over the past couple of decades. New sensor technologies and compact versatile signal recovery electronics are continuously expanding the limits of what can be measured and the accuracy with which this can be done. Miniaturization of sensors and the use of nanotechnology push these limits further. Also, thanks to powerful and cost-effective computer systems, sophisticated measurement and reconstruction algorithms previously only accessible in advanced laboratories are now available for in situ online measurement systems. The process industries increasingly require more process-related information, motivated by key issues such as improved process control, process utilization and process yields, ultimately driven by cost-effectiveness, quality assurance, environmental and safety demands. Industrial process tomography methods have taken advantage of the general progress in measurement science, and aim at providing more information, both quantitatively and qualitatively, on multiphase systems and their dynamics. The typical approach for such systems has been to carry out one local or bulk measurement and assume that this is representative of the whole system. In some cases, this is sufficient. However, there are many complex systems where the component distribution varies continuously and often unpredictably in space and time. The foundation of industrial tomography is to conduct several measurements around the periphery of a multiphase process, and use these measurements to unravel the cross-sectional distribution of the process components in time and space. This information is used in the design and optimization of industrial processes and process equipment, and also to improve the accuracy of multiphase system measurements in general. In this issue we are proud to present a selection of the 145 papers presented at the 5th World Congress on Industrial Process Tomography in Bergen

  1. Radiology interpretation process modeling.

    PubMed

    Noumeir, Rita

    2006-04-01

    Information and communication technology in healthcare promises optimized patient care while ensuring efficiency and cost-effectiveness. However, the promised results are not yet achieved; the healthcare process requires analysis and radical redesign to achieve improvements in care quality and productivity. Healthcare process reengineering is thus necessary and involves modeling its workflow. Even though the healthcare process is very large and not very well modeled yet, its sub-processes can be modeled individually, providing fundamental pieces of the whole model. In this paper, we are interested in modeling the radiology interpretation process that results in generating a diagnostic radiology report. This radiology report is an important clinical element of the patient healthcare record and assists in healthcare decisions. We present the radiology interpretation process by identifying its boundaries and by positioning it on the large healthcare process map. Moreover, we discuss an information data model and identify roles, tasks and several information flows. Furthermore, we describe standard frameworks to enable radiology interpretation workflow implementations between heterogeneous systems.

  2. Process measurement assurance program

    SciTech Connect

    Pettit, R.B.

    1996-05-01

    This paper describes a new method for determining, improving, and controlling the measurement process errors (or measurement uncertainty) of a measurement system used to monitor product as it is manufactured. The method is called the Process Measurement Assurance Program (PMAP). It integrates metrology early into the product realization process and is a step beyond statistical process control (SPC), which monitors only the product. In this method, a control standard is used to continuously monitor the status of the measurement system. Analysis of the control standard data allow the determination of the measurement error inherent in the product data and allow one to separate the variability in the manufacturing process from variability in the measurement process. These errors can be then associated with either the measurement equipment, variability of the measurement process, operator bias, or local environmental effects. Another goal of PMAP is to determine appropriate re-calibration intervals for the measurement system, which may be significantly longer or shorter than the interval typically assigned by the calibration organization.

  3. CCD gate definition process

    NASA Astrophysics Data System (ADS)

    Bluzer

    1986-02-01

    The present invention utilizes a double masking step in a CCD gate definition process to eliminate the re-entrant oxide by using a thin film layer other than photoresist to define the polysilicon gates used by defining the thin film layer with a double masking process before any of the polysilicon gate layer is etched. It is one object of the present invention, therefore, to provide an improved process for CCD gate definition. It is another object of the invention to provide an improved CCD gate definition process wherein a profiled oxide layer is produced over a polysilicon layer without re-entrant oxide regions. It is another object of the invention to provide an improved CCD gate definition process wherein a thin film layer is utilized to define the polysilicon gate layers. It is another object of the invention to provide an improved CCD gate definition process wherein the thin film layer is defined by a double masking process before any polysilicon layer is etched.

  4. Processes in Lingua Cosmica

    NASA Astrophysics Data System (ADS)

    Ollongren, Alexander

    2012-02-01

    In a sequence of papers on the topic of message construction for interstellar communication by means of a cosmic language, representations of various kinds of concepts of reality in a Lingua Cosmica system [1]. Those studied were logic relations of a static character. The present contribution contains an important, fundamental extension: groundwork is done for the purpose of interpreting (dynamic) proc esses of various sorts in the linguistic system. Individual processes are abstracted in a logic sense and provided with basic properties as termination and communication functions. They can be combined into kinds of processes: sequential and parallel ones represented by only one inductive definition in logic. Based on concepts from the so-called process algebra, processes are provided with channel s mapping them to their states. State vectors are introduced to represent states of conglomerates of processes. Communication between processes (locally or globally) is effectuated by means of state transitions. Together with a programmed arb itration function, state vectors play a crucial role in representing communication. With these ingredients possibilities for general interpretations of a wide range of processes in the Lingua Cosmica system come in view.

  5. Advanced Hydrogen Liquefaction Process

    SciTech Connect

    Schwartz, Joseph; Kromer, Brian; Neu, Ben; Jankowiak, Jerome; Barrett, Philip; Drnevich, Raymond

    2011-09-28

    The project identified and quantified ways to reduce the cost of hydrogen liquefaction, and reduce the cost of hydrogen distribution. The goal was to reduce the power consumption by 20% and then to reduce the capital cost. Optimizing the process, improving process equipment, and improving ortho-para conversion significantly reduced the power consumption of liquefaction, but by less than 20%. Because the efficiency improvement was less than the target, the program was stopped before the capital cost was addressed. These efficiency improvements could provide a benefit to the public to improve the design of future hydrogen liquefiers. The project increased the understanding of hydrogen liquefaction by modeling different processes and thoroughly examining ortho-para separation and conversion. The process modeling provided a benefit to the public because the project incorporated para hydrogen into the process modeling software, so liquefaction processes can be modeled more accurately than using only normal hydrogen. Adding catalyst to the first heat exchanger, a simple method to reduce liquefaction power, was identified, analyzed, and quantified. The demonstrated performance of ortho-para separation is sufficient for at least one identified process concept to show reduced power cost when compared to hydrogen liquefaction processes using conventional ortho-para conversion. The impact of improved ortho-para conversion can be significant because ortho para conversion uses about 20-25% of the total liquefaction power, but performance improvement is necessary to realize a substantial benefit. Most of the energy used in liquefaction is for gas compression. Improvements in hydrogen compression will have a significant impact on overall liquefier efficiency. Improvements to turbines, heat exchangers, and other process equipment will have less impact.

  6. The VISAR Process

    NASA Technical Reports Server (NTRS)

    Hathaway, David; Meyer, Paul; Templeton, Gary F.

    2003-01-01

    The Video Image Stabilization And Registration (VISAR) process is an award winning video image processing software developed at NASA's Marshall Space Flight Center. VISAR has a wide variety of application areas where the refinement of digital video is needed. It is used to correct jitter, rotation, and zoom effects by registering and processing on individual image captures that are a part of normal video capturing. Its most prominent uses were the 1996 Olympic Bombing case and in identifying Saddam Hussein during the Iraq war. Based on first-hand knowledge, this paper describes the VISAR process, which consists of several steps designed to refine digital video using VISAR software. The process determines the differences between two video images so that one, or both, of the images can be changed in ways that make them match as well as possible. Corrections include changes in position (horizontal and vertical image shifts), changes in orientation (image rotation), and changes in magnification (image zoom). While much of the VISAR process is automated, in its current embodiment it requires the user to initially identify the area of interest and to reset a threshold parameter if the default gives unacceptable results. The basic process that is used is an old tried and true method that determines how well the two images match. This process is called cross-correlation. It gives a single number, the correlation coefficient, that is equal to 1.0 if the images are perfectly matched, is equal to 0.0 if the images have nothing in common, and is equal to -1.0 if one image is the negative of the other. This basic process is used by many image stabilization methods. With VISAR we use it in a manner that provides statistical information needed to best determine orientation and magnification.

  7. The VISAR Process

    NASA Technical Reports Server (NTRS)

    Hathaway, David; Meyer, Paul; Templeton, Gary F.

    2003-01-01

    The Video Image Stabilization And Registration (VISAR) process is an award winning video image processing software developed at NASA's Marshall Space Flight Center. VISAR has a wide variety of application areas where the refinement of digital video is needed. It is used to correct jitter, rotation, and zoom effects by registering and processing on individual image captures that are a part of normal video capturing. Its most prominent uses were the 1996 Olympic Bombing case and in identifying Saddam Hussein during the Iraq war. Based on first-hand knowledge, this paper describes the VISAR process, which consists of several steps designed to refine digital video using VISAR software. The process determines the differences between two video images so that one, or both, of the images can be changed in ways that make them match as well as possible. Corrections include changes in position (horizontal and vertical image shifts), changes in orientation (image rotation), and changes in magnification (image zoom). While much of the VISAR process is automated, in its current embodiment it requires the user to initially identify the area of interest and to reset a threshold parameter if the default gives unacceptable results. The basic process that is used is an old tried and true method that determines how well the two images match. This process is called cross-correlation. It gives a single number, the correlation coefficient, that is equal to 1.0 if the images are perfectly matched, is equal to 0.0 if the images have nothing in common, and is equal to -1.0 if one image is the negative of the other. This basic process is used by many image stabilization methods. With VISAR we use it in a manner that provides statistical information needed to best determine orientation and magnification.

  8. Membrane separation processes

    SciTech Connect

    Rautenbach, R.; Albrecht, R.

    1989-01-01

    The success of two membrane processes, reverse osmosis and ultrafiltration, has helped make membrane processes a central technique in solving separation problems for fluid systems. This book discusses the various applications and developments in membrane technology and shows how accurate membrane processes can be designed. Starting with the local transport phenomena, the behavior of individual elements such as tube or plate membrane and the behavior of the technical unit - the module - are discussed in detail. The book goes on to demonstrate the most effective ways of arranging modules for forming an optimal plant.

  9. Information processing during phagocytosis

    PubMed Central

    Underhill, David M.; Goodridge, Helen S.

    2017-01-01

    Phagocytosis, the process by which macrophages, dendritic cells and other myeloid phagocytes internalize diverse particulate targets, is a key mechanism of innate immunity. The molecular and cellular events underlying the binding and engulfment of targets in phagosomes have been extensively studied. More recent data suggest that the process of phagocytosis itself provides information to myeloid phagocytes about the nature of the targets they are eating and that this helps tailor inflammatory responses. In this Review, we discuss how such information is acquired during phagocytosis, and how it is processed to coordinate an immune response. PMID:22699831

  10. Neural Analog Information Processing

    NASA Astrophysics Data System (ADS)

    Hecht-Nielsen, Robert

    1982-07-01

    Neural Analog Information Processing (NAIP) is an effort to develop general purpose pattern classification architectures based upon biological information processing principles. This paper gives an overview of NAIP and its relationship to the previous work in neural modeling from which its fundamental principles are derived. It also presents a theorem concerning the stability of response of a slab (a two dimensional array of identical simple processing units) to time-invariant (spatial) patterns. An experiment (via computer emulation) demonstrating classification of a spatial pattern by a simple, but complete NAIP architecture is described. A concept for hardware implementation of NAIP architectures is briefly discussed.

  11. Mechanical processes in biochemistry.

    PubMed

    Bustamante, Carlos; Chemla, Yann R; Forde, Nancy R; Izhaky, David

    2004-01-01

    Mechanical processes are involved in nearly every facet of the cell cycle. Mechanical forces are generated in the cell during processes as diverse as chromosomal segregation, replication, transcription, translation, translocation of proteins across membranes, cell locomotion, and catalyzed protein and nucleic acid folding and unfolding, among others. Because force is a product of all these reactions, biochemists are beginning to directly apply external forces to these processes to alter the extent or even the fate of these reactions hoping to reveal their underlying molecular mechanisms. This review provides the conceptual framework to understand the role of mechanical force in biochemistry.

  12. Coal liquefaction quenching process

    DOEpatents

    Thorogood, Robert M.; Yeh, Chung-Liang; Donath, Ernest E.

    1983-01-01

    There is described an improved coal liquefaction quenching process which prevents the formation of coke with a minimum reduction of thermal efficiency of the coal liquefaction process. In the process, the rapid cooling of the liquid/solid products of the coal liquefaction reaction is performed without the cooling of the associated vapor stream to thereby prevent formation of coke and the occurrence of retrograde reactions. The rapid cooling is achieved by recycling a subcooled portion of the liquid/solid mixture to the lower section of a phase separator that separates the vapor from the liquid/solid products leaving the coal reactor.

  13. Chemical Processing Manual

    NASA Technical Reports Server (NTRS)

    Beyerle, F. J.

    1972-01-01

    Chemical processes presented in this document include cleaning, pickling, surface finishes, chemical milling, plating, dry film lubricants, and polishing. All types of chemical processes applicable to aluminum, for example, are to be found in the aluminum alloy section. There is a separate section for each category of metallic alloy plus a section for non-metals, such as plastics. The refractories, super-alloys and titanium, are prime candidates for the space shuttle, therefore, the chemical processes applicable to these alloys are contained in individual sections of this manual.

  14. Troubleshooting refinery processes

    SciTech Connect

    Lieberman, N.P.

    1981-01-01

    A reference guide that is designed to help petroleum refinery process engineers to locate and solve refinery problems is presented. At the end of each chapter a troubleshooting guide is presented, outlining possible causes of the problem and solutions. The contents include: crude unit; delayed coking cycles; delayed coking process; amine regeneration and scrubbing; sulfur recovery; alkylation; saving energy at reduced feed rates; refrigeration systems; centrifugal pumps; distillation towers; vacuum towers; treating liquid hydrocarbons; process heaters; water coolers; alarms and trips; unstable gas plant operations; fouled trays; dehydrating light ends towers; vapor-liquid separation; refinery metallurgy; unusual noises and vibrations; planning performance tests; and control board instruments. (JMT)

  15. Carbon wastewater treatment process

    NASA Technical Reports Server (NTRS)

    Humphrey, M. F.; Simmons, G. M.; Dowler, W. L.

    1974-01-01

    A new powdered-carbon treatment process is being developed for the elimination of the present problems, associated with the disposal of biologically active sewage waste solids, and with water reuse. This counter-current flow process produces an activated carbon, which is obtained from the pyrolysis of the sewage solids, and utilizes this material to remove the adulterating materials from the water. Additional advantages of the process are the elimination of odors, the removal of heavy metals, and the potential for energy conservation.

  16. Municipal waste processing apparatus

    DOEpatents

    Mayberry, J.L.

    1988-04-13

    This invention relates to apparatus for processing municipal waste, and more particularly to vibrating mesh screen conveyor systems for removing grit, glass, and other noncombustible materials from dry municipal waste. Municipal waste must be properly processed and disposed of so that it does not create health risks to the community. Generally, municipal waste, which may be collected in garbage trucks, dumpsters, or the like, is deposited in processing areas such as landfills. Land and environmental controls imposed on landfill operators by governmental bodies have increased in recent years, however, making landfill disposal of solid waste materials more expensive. 6 figs.

  17. Advances in metals processing

    NASA Technical Reports Server (NTRS)

    Bales, T. T.; Royster, D. M.

    1982-01-01

    Research on metals processing being conducted to develop improved forming and joining methods with the potential of reducing the weight and cost of future aerospace structures is discussed. The approach followed is to assess the state of the art for fabricating a given structural system, define candidate methods for improving processing, evaluate the merits of each, fabricate and test subelement components, and then scale up the process to demonstrate validity. The development and the state of the art of weldbrazing, superplastic forming (SPF), superplastic forming and codiffusion bonding and superplastic forming and weldbrazing for titanium and the SPF of aluminum is discussed.

  18. Robot welding process control

    NASA Technical Reports Server (NTRS)

    Romine, Peter L.

    1991-01-01

    This final report documents the development and installation of software and hardware for Robotic Welding Process Control. Primary emphasis is on serial communications between the CYRO 750 robotic welder, Heurikon minicomputer running Hunter & Ready VRTX, and an IBM PC/AT, for offline programming and control and closed-loop welding control. The requirements for completion of the implementation of the Rocketdyne weld tracking control are discussed. The procedure for downloading programs from the Intergraph, over the network, is discussed. Conclusions are made on the results of this task, and recommendations are made for efficient implementation of communications, weld process control development, and advanced process control procedures using the Heurikon.

  19. Precision Heating Process

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A heat sealing process was developed by SEBRA based on technology that originated in work with NASA's Jet Propulsion Laboratory. The project involved connecting and transferring blood and fluids between sterile plastic containers while maintaining a closed system. SEBRA markets the PIRF Process to manufacturers of medical catheters. It is a precisely controlled method of heating thermoplastic materials in a mold to form or weld catheters and other products. The process offers advantages in fast, precise welding or shape forming of catheters as well as applications in a variety of other industries.

  20. Carbon wastewater treatment process

    NASA Technical Reports Server (NTRS)

    Humphrey, M. F.; Simmons, G. M.; Dowler, W. L.

    1974-01-01

    A new powdered-carbon treatment process is being developed for the elimination of the present problems, associated with the disposal of biologically active sewage waste solids, and with water reuse. This counter-current flow process produces an activated carbon, which is obtained from the pyrolysis of the sewage solids, and utilizes this material to remove the adulterating materials from the water. Additional advantages of the process are the elimination of odors, the removal of heavy metals, and the potential for energy conservation.

  1. Lubricant Coating Process

    NASA Technical Reports Server (NTRS)

    1989-01-01

    "Peen Plating," a NASA developed process for applying molybdenum disulfide, is the key element of Techniblast Co.'s SURFGUARD process for applying high strength solid lubricants. The process requires two machines -- one for cleaning and one for coating. The cleaning step allows the coating to be bonded directly to the substrate to provide a better "anchor." The coating machine applies a half a micron thick coating. Then, a blast gun, using various pressures to vary peening intensities for different applications, fires high velocity "media" -- peening hammers -- ranging from plastic pellets to steel shot. Techniblast was assisted by Rural Enterprises, Inc. Coating service can be performed at either Techniblast's or a customer's facility.

  2. Ultrasonic Processing of Materials

    SciTech Connect

    Meek, Thomas T.; Han, Qingyou; Jian, Xiaogang; Xu, Hanbing

    2005-06-30

    The purpose of this project was to determine the impact of a new breakthrough technology, ultrasonic processing, on various industries, including steel, aluminum, metal casting, and forging. The specific goals of the project were to evaluate core principles and establish quantitative bases for the ultrasonc processing of materials, and to demonstrate key applications in the areas of grain refinement of alloys during solidification and degassing of alloy melts. This study focussed on two classes of materials - aluminum alloys and steels - and demonstrated the application of ultrasonic processing during ingot casting.

  3. Metal finishing and processing

    SciTech Connect

    Enzminger, J.D. )

    1990-06-01

    This article reviews the finishing and processing of metal wastes for land disposal. Topics of discussion include regulatory aspects, heavy metal treatment, cyanide treatment, waste minimization programs and techniques, and sludge treatment.

  4. Log processing systems

    SciTech Connect

    Bowlin, W.P.; Kneer, M.P.; Ballance, J.D.

    1989-11-07

    This patent describes an improvement in a computer controlled processing system for lumber production. It comprises: a computer, a sequence of processing stations for processing a log segment including; an excess material removing station for generating opposed flat side surfaces on the log segment. The flat side surfaces determined by the computer to become sides of boards to be severed from the log segments; a profiling station for forming profiled edges above and below the flat side surfaces to become the side edges of the boards to be severed from the log segment, and a severing station for severing the boards from the log segments, a conveyance means establishing a path of conveyance and having continuous control of the log segment on conveying the log segment along the path and through the above defined sequence of processing stations.

  5. Petroleum Processing Wastes.

    ERIC Educational Resources Information Center

    Baker, D. A.

    1978-01-01

    Presents a literature review of the petroleum processing wastes, covering publications of 1977. This review covers studies such as the use of activated carbon in petroleum and petrochemical waste treatment. A list of 15 references is also presented. (HM)

  6. Quantum Stochastic Processes

    SciTech Connect

    Spring, William Joseph

    2009-04-13

    We consider quantum analogues of n-parameter stochastic processes, associated integrals and martingale properties extending classical results obtained in [1, 2, 3], and quantum results in [4, 5, 6, 7, 8, 9, 10].

  7. [The irradiation process].

    PubMed

    Barillot, I; Chauvet, B; Hannoun Lévi, J M; Lisbona, A; Leroy, T; Mahé, M A

    2016-09-01

    The purpose of this article is to describe the regulatory framework of the radiotherapy practice in France, the external irradiation and brachytherapy process and the guidelines for patient follow-up.

  8. Processing composite materials

    NASA Technical Reports Server (NTRS)

    Baucom, R. M.

    1982-01-01

    The fabrication of several composite structural articles including DC-10 upper aft rudders, L-1011 vertical fins and composite biomedical appliances are discussed. Innovative composite processing methods are included.

  9. George: Gaussian Process regression

    NASA Astrophysics Data System (ADS)

    Foreman-Mackey, Daniel

    2015-11-01

    George is a fast and flexible library, implemented in C++ with Python bindings, for Gaussian Process regression useful for accounting for correlated noise in astronomical datasets, including those for transiting exoplanet discovery and characterization and stellar population modeling.

  10. Ultrasonic Processing of Materials

    NASA Astrophysics Data System (ADS)

    Han, Qingyou

    2015-08-01

    Irradiation of high-energy ultrasonic vibration in metals and alloys generates oscillating strain and stress fields in solids, and introduces nonlinear effects such as cavitation, acoustic streaming, and radiation pressure in molten materials. These nonlinear effects can be utilized to assist conventional material processing processes. This article describes recent research at Oak Ridge National Labs and Purdue University on using high-intensity ultrasonic vibrations for degassing molten aluminum, processing particulate-reinforced metal matrix composites, refining metals and alloys during solidification process and welding, and producing bulk nanostructures in solid metals and alloys. Research results suggest that high-intensity ultrasonic vibration is capable of degassing and dispersing small particles in molten alloys, reducing grain size during alloy solidification, and inducing nanostructures in solid metals.

  11. Cooperative processing data bases

    NASA Technical Reports Server (NTRS)

    Hasta, Juzar

    1991-01-01

    Cooperative processing for the 1990's using client-server technology is addressed. The main theme is concepts of downsizing from mainframes and minicomputers to workstations on a local area network (LAN). This document is presented in view graph form.

  12. Phenol removal pretreatment process

    DOEpatents

    Hames, Bonnie R.

    2004-04-13

    A process for removing phenols from an aqueous solution is provided, which comprises the steps of contacting a mixture comprising the solution and a metal oxide, forming a phenol metal oxide complex, and removing the complex from the mixture.

  13. Plants: Novel Developmental Processes.

    ERIC Educational Resources Information Center

    Goldberg, Robert B.

    1988-01-01

    Describes the diversity of plants. Outlines novel developmental and complex genetic processes that are specific to plants. Identifies approaches that can be used to solve problems in plant biology. Cites the advantages of using higher plants for experimental systems. (RT)

  14. Associative list processing unit

    SciTech Connect

    Hemmert, Karl Scott; Underwood, Keith D

    2014-04-01

    An associative list processing unit and method comprising employing a plurality of prioritized cell blocks and permitting inserts to occur in a single clock cycle if all of the cell blocks are not full.

  15. Microwave processing of ceramics

    SciTech Connect

    Katz, J.D.

    1989-01-01

    This paper discusses the following topics on microwave processing of ceramics: Microwave-material interactions; anticipated advantage of microwave sintering; ceramic sintering; and ceramic joining. 24 refs., 4 figs. (LSP)

  16. Space processing economics

    NASA Technical Reports Server (NTRS)

    Bredt, J. H.

    1974-01-01

    Two types of space processing operations may be considered economically justified; they are manufacturing operations that make profits and experiment operations that provide needed applied research results at lower costs than those of alternative methods. Some examples from the Skylab experiments suggest that applied research should become cost effective soon after the space shuttle and Spacelab become operational. In space manufacturing, the total cost of space operations required to process materials must be repaid by the value added to the materials by the processing. Accurate estimates of profitability are not yet possible because shuttle operational costs are not firmly established and the markets for future products are difficult to estimate. However, approximate calculations show that semiconductor products and biological preparations may be processed on a scale consistent with market requirements and at costs that are at least compatible with profitability using the Shuttle/Spacelab system.

  17. Superfund Site Assessment Process

    EPA Pesticide Factsheets

    Learn about the site assessment process used by the federal Superfund program to evaluate releases of hazardous substances that may pose a threat to human health or the environment and select an appropriate program for sites needing cleanup.

  18. Advances in Process Control.

    ERIC Educational Resources Information Center

    Morrison, David L.; And Others

    1982-01-01

    Advances in electronics and computer science have enabled industries (pulp/paper, iron/steel, petroleum/chemical) to attain better control of their processes with resulting increases in quality, productivity, profitability, and compliance with government regulations. (JN)

  19. CAPSULE REPORT: EVAPORATION PROCESS

    EPA Science Inventory

    Evaporation has been an established technology in the metal finishing industry for many years. In this process, wastewaters containing reusable materials, such as copper, nickel, or chromium compounds are heated, producing a water vapor that is continuously removed and condensed....

  20. Coal Liquefaction Processes.

    ERIC Educational Resources Information Center

    Yen, T. F.

    1979-01-01

    Described is a graduate level engineering course offered at the University of Southern California on coal liquefaction processes. Lecture topics and course requirements are discussed. A 64-item bibliography of papers used in place of a textbook is included. (BT)

  1. Direct coal liquefaction process

    DOEpatents

    Rindt, J.R.; Hetland, M.D.

    1993-10-26

    An improved multistep liquefaction process for organic carbonaceous mater which produces a virtually completely solvent-soluble carbonaceous liquid product. The solubilized product may be more amenable to further processing than liquid products produced by current methods. In the initial processing step, the finely divided organic carbonaceous material is treated with a hydrocarbonaceous pasting solvent containing from 10% and 100% by weight process-derived phenolic species at a temperature within the range of 300 C to 400 C for typically from 2 minutes to 120 minutes in the presence of a carbon monoxide reductant and an optional hydrogen sulfide reaction promoter in an amount ranging from 0 to 10% by weight of the moisture- and ash-free organic carbonaceous material fed to the system. As a result, hydrogen is generated via the water/gas shift reaction at a rate necessary to prevent condensation reactions. In a second step, the reaction product of the first step is hydrogenated.

  2. Coal Liquefaction Processes.

    ERIC Educational Resources Information Center

    Yen, T. F.

    1979-01-01

    Described is a graduate level engineering course offered at the University of Southern California on coal liquefaction processes. Lecture topics and course requirements are discussed. A 64-item bibliography of papers used in place of a textbook is included. (BT)

  3. Direct coal liquefaction process

    DOEpatents

    Rindt, John R.; Hetland, Melanie D.

    1993-01-01

    An improved multistep liquefaction process for organic carbonaceous mater which produces a virtually completely solvent-soluble carbonaceous liquid product. The solubilized product may be more amenable to further processing than liquid products produced by current methods. In the initial processing step, the finely divided organic carbonaceous material is treated with a hydrocarbonaceous pasting solvent containing from 10% and 100% by weight process-derived phenolic species at a temperature within the range of 300.degree. C. to 400.degree. C. for typically from 2 minutes to 120 minutes in the presence of a carbon monoxide reductant and an optional hydrogen sulfide reaction promoter in an amount ranging from 0 to 10% by weight of the moisture- and ash-free organic carbonaceous material fed to the system. As a result, hydrogen is generated via the water/gas shift reaction at a rate necessary to prevent condensation reactions. In a second step, the reaction product of the first step is hydrogenated.

  4. CAPSULE REPORT: EVAPORATION PROCESS

    EPA Science Inventory

    Evaporation has been an established technology in the metal finishing industry for many years. In this process, wastewaters containing reusable materials, such as copper, nickel, or chromium compounds are heated, producing a water vapor that is continuously removed and condensed....

  5. Petroleum Processing Wastes.

    ERIC Educational Resources Information Center

    Baker, D. A.

    1978-01-01

    Presents a literature review of the petroleum processing wastes, covering publications of 1977. This review covers studies such as the use of activated carbon in petroleum and petrochemical waste treatment. A list of 15 references is also presented. (HM)

  6. Shaping process makes fuels

    SciTech Connect

    Tabak, S.A.; Krambeck, F.J.

    1985-09-01

    The Mobil Olefin to Gasoline and Distillate (MOGD) process is described in which light olefinic compunds can be converted to high quality gasoline and distillate. This process, now ready for commercialization is based on a unique synthetic zeolite catalyst, the shape of which selectively oligomerizes light olefins to higher molecular weight iso-olefins. The highly flexible process can be designed to produce distillate/gasoline ratios of 0/100 to 90/10 for a commercial plant, depending on market requirements. MOGD is applicable to a wide range of feed streams ranging from ethylene to 400 degrees F end point olefinic naphtha. The process has been tested using commercially produced catalyst in refinery-scale equipment.

  7. Process for preparing hydrocarbons

    SciTech Connect

    Breuker, J.H.; De H.H.; Kwant, P.B.

    1980-01-15

    A process for preparing light distillate fractions and medicinal oil from heavy hydrocarbon oils comprises two-stage hydrocracking, fractionation distillation and catalytic hydrotreatment of at least part of the fractionation residue.

  8. Lesson 6: Submission Process

    EPA Pesticide Factsheets

    Checklist items 8 through 12 are grouped under the Submission Process, and represent the CROMERR requirements that must be satisfied as the report or document is transferred to the system during a formal submission.

  9. Plants: Novel Developmental Processes.

    ERIC Educational Resources Information Center

    Goldberg, Robert B.

    1988-01-01

    Describes the diversity of plants. Outlines novel developmental and complex genetic processes that are specific to plants. Identifies approaches that can be used to solve problems in plant biology. Cites the advantages of using higher plants for experimental systems. (RT)

  10. Advances in Process Control.

    ERIC Educational Resources Information Center

    Morrison, David L.; And Others

    1982-01-01

    Advances in electronics and computer science have enabled industries (pulp/paper, iron/steel, petroleum/chemical) to attain better control of their processes with resulting increases in quality, productivity, profitability, and compliance with government regulations. (JN)

  11. Image Processing Software

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Ames digital image velocimetry technology has been incorporated in a commercially available image processing software package that allows motion measurement of images on a PC alone. The software, manufactured by Werner Frei Associates, is IMAGELAB FFT. IMAGELAB FFT is a general purpose image processing system with a variety of other applications, among them image enhancement of fingerprints and use by banks and law enforcement agencies for analysis of videos run during robberies.

  12. Near Shore Wave Processes

    DTIC Science & Technology

    2016-06-07

    given the offshore wave conditions . OBJECTIVES We hypothesize that the wave-induced kinematic, sediment and morphologic processes are nonlinearly... WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Postgraduate School,Department of Oceanography,Monterey,CA,93943 8...basis of our process modeling and analysis work . In addition, the comprehensive Delft3D morphology model was acquired from the Dutch and is being assessed

  13. Materials Processing in Space

    NASA Technical Reports Server (NTRS)

    Naumann, R. J.

    1982-01-01

    A report describes investigations of materials processing in low-gravity environment. Ultimately, research could lead to new commercially-applicable materials and processes and to an understanding of constraints imposed by gravity. NASA-supported work is carried out in 46 academic, industrial, and Government laboratories, and covers a number of areas. An overview is given of objective and current state of development for over 100 tasks.

  14. Advanced Polymer Processing Facility

    SciTech Connect

    Muenchausen, Ross E.

    2012-07-25

    Some conclusions of this presentation are: (1) Radiation-assisted nanotechnology applications will continue to grow; (2) The APPF will provide a unique focus for radiolytic processing of nanomaterials in support of DOE-DP, other DOE and advanced manufacturing initiatives; (3) {gamma}, X-ray, e-beam and ion beam processing will increasingly be applied for 'green' manufacturing of nanomaterials and nanocomposites; and (4) Biomedical science and engineering may ultimately be the biggest application area for radiation-assisted nanotechnology development.

  15. Bank Record Processing

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Barnett Banks of Florida, Inc. operates 150 banking offices in 80 Florida cities. Banking offices have computerized systems for processing deposits or withdrawals in checking/savings accounts, and for handling commercial and installment loan transactions. In developing a network engineering design for the terminals used in record processing, an affiliate, Barnett Computing Company, used COSMIC's STATCOM program. This program provided a reliable network design tool and avoided the cost of developing new software.

  16. Research in Stochastic Processes.

    DTIC Science & Technology

    1985-09-01

    appear. G. Kallianpur, Finitely additive approach to nonlinear filtering, Proc. Bernoulli Soc. Conf. on Stochastic Processes, T. Hida , ed., Springer, to...Nov. 85, in Proc. Bernoulli Soc. Conf. on Stochastic Processes, T. Hida , ed., Springer, to appear. i. Preparation T. Hsing, Extreme value theory for...1507 Carroll, R.J., Spiegelman, C.H., Lan, K.K.G., Bailey , K.T. and Abbott, R.D., Errors in-variables for binary regression models, Aug.82. 1508

  17. Solution Processing - Rodlike Polymers

    DTIC Science & Technology

    1979-08-01

    side it necessary and identify by block number) Para-ordered Polymers High Modulus Fibers and Films Polybenzobisoxazoles Polybenzobisthiazoles 20...considerations important in solution processing are considered, with special emphasis on the dry-jet wet spinning process used to form fibers . Pertinent...Company, Summit, N.J. iii TABLE OF CONTENTS 1. INTRODUCTION ................ .......................... .. 1 2. REMARKS ON DRY-JET WET SPUN FIBER

  18. Coal liquefaction process

    DOEpatents

    Karr, Jr., Clarence

    1977-04-19

    An improved coal liquefaction process is provided which enables conversion of a coal-oil slurry to a synthetic crude refinable to produce larger yields of gasoline and diesel oil. The process is characterized by a two-step operation applied to the slurry prior to catalytic desulfurization and hydrogenation in which the slurry undergoes partial hydrogenation to crack and hydrogenate asphaltenes and the partially hydrogenated slurry is filtered to remove minerals prior to subsequent catalytic hydrogenation.

  19. Business Development Process

    DTIC Science & Technology

    2001-10-31

    entity’s real estate situation and condition for use by 17 customers including (but not limited to) the business entity. 18 Information is processed to...the score to provide a well- 3 rounded picture of a particular real estate situation. 4 Stratmann discloses a method for assisting an individual in...identify a potential 9 flaw in the opportunity analysis . These criteria include whether 10 the process is dealing with a real customer, if it is

  20. Retrofitting heavy oil processes

    SciTech Connect

    Hamilton, G.L.; Fitzgerald, M.; D'Amico, V.

    1986-01-01

    Refiners, faced with the need to process the bottom end of the heavy high sulfur crude oil barrel in today's uncertain economic environment, are reluctant to commit large amounts of money to expensive upgrading processes. In order to conserve scarce capital while improving operating margins, additional valuable products can be produced by retrofits such as conversion of an idle crude unit to visbreaking, delayed coking or deasphalting service, or conversion of hydrodesulfurizers to mild hydrocracking.