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1

atmosphere boundary layer: Topics by E-print Network  

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

Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

2

atmospheric boundary layer: Topics by E-print Network  

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

Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

3

atmospheric boundary layers: Topics by E-print Network  

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

Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

4

ARM - Field Campaign - Lower Atmospheric Boundary Layer Experiment  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience4AJ01)3,CloudgovCampaignsIR CloudgovCampaignsLower Atmospheric

5

Wave-driven wind jets in the marine atmospheric boundary layer  

E-Print Network [OSTI]

Wave-driven wind jets in the marine atmospheric boundary layer Kirsty E. Hanley Stephen E. Belcher;Abstract The interaction between ocean surface waves and the overlying wind leads to a transfer of momentum can also be transferred upwards when long wavelength waves, characteristic of re- motely generated

Reading, University of

6

Atmospheric Environment 34 (2000) 2851}2863 Resolution of pollutant concentrations in the boundary layer  

E-Print Network [OSTI]

Atmospheric Environment 34 (2000) 2851}2863 Resolution of pollutant concentrations in the boundary 1999 Abstract This paper investigates the solution of a 3D atmospheric dispersion problem using a time to solve the atmospheric di!usion equation. Preliminary studies of dispersion from a single source

Utah, University of

7

Stability and Turbulence in the Atmospheric Boundary Layer: A Comparison of Remote Sensing and Tower Observations  

SciTech Connect (OSTI)

When monitoring winds and atmospheric stability for wind energy applications, remote sensing instruments present some advantages to in-situ instrumentation such as larger vertical extent, in some cases easy installation and maintenance, measurements of vertical humidity profiles throughout the boundary layer, and no restrictions on prevailing wind directions. In this study, we compare remote sensing devices, Windcube lidar and microwave radiometer, to meteorological in-situ tower measurements to demonstrate the accuracy of these measurements and to assess the utility of the remote sensing instruments in overcoming tower limitations. We compare temperature and wind observations, as well as calculations of Brunt-Vaisala frequency and Richardson numbers for the instrument deployment period in May-June 2011 at the U.S. Department of Energy National Renewable Energy Laboratory's National Wind Technology Center near Boulder, Colorado. The study reveals that a lidar and radiometer measure wind and temperature with the same accuracy as tower instruments, while also providing advantages for monitoring stability and turbulence. We demonstrate that the atmospheric stability is determined more accurately when the liquid-water mixing ratio derived from the vertical humidity profile is considered under moist-adiabatic conditions.

Friedrich, K.; Lundquist, J. K.; Aitken, M.; Kalina, E. A.; Marshall, R. F.

2012-01-01T23:59:59.000Z

8

antarctic boundary layer: Topics by E-print Network  

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

Geosciences Websites Summary: Boundary Layer Meteorology (METR 5103) Spring 2014 Syllabus General information Fundamentals of the atmospheric boundary layer dynamics and...

9

atmosperic boundary layer: Topics by E-print Network  

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

Geosciences Websites Summary: Boundary Layer Meteorology (METR 5103) Spring 2014 Syllabus General information Fundamentals of the atmospheric boundary layer dynamics and...

10

Experimental development of the predictive relations for the eddy exchange coefficients for momentum and heat in the atmospheric boundary layer  

E-Print Network [OSTI]

, increase in w by removing the dummy -1 bases was 4. 2 cm/sec , and u for these runs was 330 cm/sec -I ?? Using sin [w/u] as a measure of the tilt of the wind field gave an inclination of . 72', in fair agreement with KAIMAL's relation. Therefore.... '?'illlam H. Clayton Direct measurements of the eddy fluxes of mo. . . entum and heat were. made in the atmospheric boundary layer simultaneously with measurements of the profiles of average wind velocity and tempera- ture to evaluate the capability...

Jensen, Paul Alfred

2012-06-07T23:59:59.000Z

11

Wake Turbulence of Two NREL 5-MW Wind Turbines Immersed in a Neutral Atmospheric Boundary-Layer Flow  

E-Print Network [OSTI]

The fluid dynamics video considers an array of two NREL 5-MW turbines separated by seven rotor diameters in a neutral atmospheric boundary layer (ABL). The neutral atmospheric boundary-layer flow data were obtained from a precursor ABL simulation using a Large-Eddy Simulation (LES) framework within OpenFOAM. The mean wind speed at hub height is 8m/s, and the surface roughness is 0.2m. The actuator line method (ALM) is used to model the wind turbine blades by means of body forces added to the momentum equation. The fluid dynamics video shows the root and tip vortices emanating from the blades from various viewpoints. The vortices become unstable and break down into large-scale turbulent structures. As the wakes of the wind turbines advect further downstream, smaller-scale turbulence is generated. It is apparent that vortices generated by the blades of the downstream wind turbine break down faster due to increased turbulence levels generated by the wake of the upstream wind turbine.

Bashioum, Jessica L; Schmitz, Sven; Duque, Earl P N

2013-01-01T23:59:59.000Z

12

Acidbase chemical reaction model for nucleation rates in the polluted atmospheric boundary layer  

E-Print Network [OSTI]

Atmospheric Sciences Division, Brookhaven National Laboratory, Upton, NY 11973; f Sustainable Energy Systems Group, Environmental Energy Technologies Division, E. O. Lawrence Berkeley National Laboratory, Berkeley agreement with measurements from Mexico City and Atlanta. amines | atmospheric aerosol | climate forcing

13

Ice at the Interface: Atmosphere-Ice-Ocean Boundary Layer Processes and Their Role in Polar Change---Workshop Report  

SciTech Connect (OSTI)

The atmosphere-ocean boundary layer in which sea ice resides includes many complex processes that require a more realistic treatment in GCMs, particularly as models move toward full earth system descriptions. The primary purpose of the workshop was to define and discuss such coupled processes from observational and modeling points of view, including insight from both the Arctic and Antarctic systems. The workshop met each of its overarching goals, including fostering collaboration among experimentalists, theorists and modelers, proposing modeling strategies, and ascertaining data availability and needs. Several scientific themes emerged from the workshop, such as the importance of episodic or extreme events, precipitation, stratification above and below the ice, and the marginal ice zone, whose seasonal Arctic migrations now traverse more territory than in the past.

Hunke, Elizabeth C. [Los Alamos National Laboratory

2012-07-23T23:59:59.000Z

14

investigating the source, transport, and isotope fractionation of water vapor in the atmospheric boundary layer  

E-Print Network [OSTI]

investigating the source, transport, and isotope fractionation of water vapor in the atmospheric-portable mixing ratio generator and Rayleigh distillation device, Agricultural and Forest Meteorology, 150, 1607 ratio generator. Incom- ing dry air passes through a molecular sieve and then a stainless steel frit (a

Minnesota, University of

15

Boundary Layer The U.S. Department of Energy's Atmospheric Radiation  

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

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16

Wind Energy and the Turbulent Nature of the Atmospheric Boundary Layer  

E-Print Network [OSTI]

The challenge of developing a sustainable and renewable energy supply within the next decades requires collaborative efforts as well as new concepts in the fields of science and engineering. Here we give an overview on the impact of small-scale properties of atmospheric turbulence on the wind energy conversion process. Special emphasis is given to the noisy and intermittent structure of turbulence and its outcome for wind energy conversion and utilization. Experimental, theoretical, analytical, and numerical concepts and methods are presented. In particular we report on new aspects resulting from the combination of basic research, especially in the field of turbulence and complex stochastic systems, with engineering applications.

Wächter, Matthias; Hölling, Michael; Morales, Allan; Milan, Patrick; Mücke, Tanja; Peinke, Joachim; Reinke, Nico; Rinn, Philip

2012-01-01T23:59:59.000Z

17

An investigation of the diabatic wind profile in the atmospheric boundary layer  

E-Print Network [OSTI]

in the study; in particular, thanks are extended to Mr. B. Jesse Eckalkamp for his assistance, Mrs. Linda Alexander for typing the final copy, and Mrs. Maxine Pulaski for drafting the figures. The National Space and Aeronautics Administration must...; and the potential temperature at the surface, 8 . After M & 0, the scale 0 length is derived from these quantities by letting Ue be used in place of r /o and H/pc be used in the place of H. since 8 varies little 0 P in the layer concerned, it may be regarded as a...

O'Brien, James Joseph

1964-01-01T23:59:59.000Z

18

A case study of boundary layer ventilation by convection and coastal processes  

E-Print Network [OSTI]

of the pollution in the atmosphere originates from emissions in the atmospheric boundary layer, the region; published 12 September 2007. [1] It is often assumed that ventilation of the atmospheric boundary layer responsible for ventilation of the atmospheric boundary layer during a nonfrontal day that occurred on 9 May

Dacre, Helen

19

atmospheric superficial layer: Topics by E-print Network  

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

Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

20

Isolating Effects of Water Table Dynamics, Terrain, and Soil Moisture Heterogeneity on the Atmospheric Boundary Layer Using Coupled Models  

E-Print Network [OSTI]

boundary conditions of wind, potential temperature, andvariables such as winds, potential temperature, rainfall,variables such as wind speed, potential temperature, and

Rihani, Jehan

2010-01-01T23:59:59.000Z

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


21

A study of atmosphere-ocean interaction using a one-dimensional numerical air-sea boundary layer model  

E-Print Network [OSTI]

surface with no allowance for exchange induced by wave action. The model does produce reasonable solutions, in comparison with oceanic data, for the response of the lower atmosphere and the upper ocean to specific. sets of meteorological and oceanic.../2 this function is of the form f(Ri) = (1 + b Ri) , then one obtains ? 3 1/2 2 -1 K (z) = K 62 (gX ) exp(z/W) (z/I + rdI) (1 + b Ri) hw 1 (61) Although KITAIGORODSKII (1961) does not give a specific value of b, it would appear that b = 10/3 would be in line...

Hebenstreit, Gerald Thomas

1974-01-01T23:59:59.000Z

22

Cyclone separator having boundary layer turbulence control  

DOE Patents [OSTI]

A cyclone separator including boundary layer turbulence control that is operable to prevent undue build-up of particulate material at selected critical areas on the separator walls, by selectively varying the fluid pressure at those areas to maintain the momentum of the vortex, thereby preventing particulate material from inducing turbulence in the boundary layer of the vortical fluid flow through the separator.

Krishna, Coimbatore R. (Mt. Sinai, NY); Milau, Julius S. (Port Jefferson, NY)

1985-01-01T23:59:59.000Z

23

ENTROPY BOUNDARY LAYERS FRANCK SUEUR  

E-Print Network [OSTI]

on the boundary. These conditions are used in a reduction of the system. We construct BKW expansions at all order

Sueur, Franck

24

Energy transport using natural convection boundary layers  

SciTech Connect (OSTI)

Natural convection is one of the major modes of energy transport in passive solar buildings. There are two primary mechanisms for natural convection heat transport through an aperture between building zones: (1) bulk density differences created by temperature differences between zones; and (2) thermosyphon pumping created by natural convection boundary layers. The primary objective of the present study is to compare the characteristics of bulk density driven and boundary layer driven flow, and discuss some of the advantages associated with the use of natural convection boundary layers to transport energy in solar building applications.

Anderson, R.

1986-04-01T23:59:59.000Z

25

Boundary Layer Cloud Turbulence Characteristics  

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

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26

TURBULENCE IN SUPERSONIC AND HYPERSONIC BOUNDARY LAYERS  

E-Print Network [OSTI]

TURBULENCE IN SUPERSONIC AND HYPERSONIC BOUNDARY LAYERS Alexander J. Smits and M. Pino Martin in supersonic and hypersonic flow where the effects of compressibility have a direct influence on the turbulence. Experimental and DNS results are presented and compared. Key words: Turbulence, supersonic, hypersonic, shocks

MartĂ­n, Pino

27

Planetary Boundary Layer from AERI and MPL  

SciTech Connect (OSTI)

The distribution and transport of aerosol emitted to the lower troposphere is governed by the height of the planetary boundary layer (PBL), which limits the dilution of pollutants and influences boundary-layer convection. Because radiative heating and cooling of the surface strongly affect the PBL top height, it follows diurnal and seasonal cycles and may vary by hundreds of meters over a 24-hour period. The cap the PBL imposes on low-level aerosol transport makes aerosol concentration an effective proxy for PBL height: the top of the PBL is marked by a rapid transition from polluted, well-mixed boundary-layer air to the cleaner, more stratified free troposphere. Micropulse lidar (MPL) can provide much higher temporal resolution than radiosonde and better vertical resolution than infrared spectrometer (AERI), but PBL heights from all three instruments at the ARM SGP site are compared to one another for validation. If there is agreement among them, the higher-resolution remote sensing-derived PBL heights can accurately fill in the gaps left by the low frequency of radiosonde launches, and thus improve model parameterizations and our understanding of boundary-layer processes.

Sawyer, Virginia

2014-02-13T23:59:59.000Z

28

Planetary Boundary Layer from AERI and MPL  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The distribution and transport of aerosol emitted to the lower troposphere is governed by the height of the planetary boundary layer (PBL), which limits the dilution of pollutants and influences boundary-layer convection. Because radiative heating and cooling of the surface strongly affect the PBL top height, it follows diurnal and seasonal cycles and may vary by hundreds of meters over a 24-hour period. The cap the PBL imposes on low-level aerosol transport makes aerosol concentration an effective proxy for PBL height: the top of the PBL is marked by a rapid transition from polluted, well-mixed boundary-layer air to the cleaner, more stratified free troposphere. Micropulse lidar (MPL) can provide much higher temporal resolution than radiosonde and better vertical resolution than infrared spectrometer (AERI), but PBL heights from all three instruments at the ARM SGP site are compared to one another for validation. If there is agreement among them, the higher-resolution remote sensing-derived PBL heights can accurately fill in the gaps left by the low frequency of radiosonde launches, and thus improve model parameterizations and our understanding of boundary-layer processes.

Sawyer, Virginia

29

Viscous drag reduction in boundary layers  

SciTech Connect (OSTI)

The present volume discusses the development status of stability theory for laminar flow control design, applied aspects of laminar-flow technology, transition delays using compliant walls, the application of CFD to skin friction drag-reduction, active-wave control of boundary-layer transitions, and such passive turbulent-drag reduction methods as outer-layer manipulators and complex-curvature concepts. Also treated are such active turbulent drag-reduction technique applications as those pertinent to MHD flow drag reduction, as well as drag reduction in liquid boundary layers by gas injection, drag reduction by means of polymers and surfactants, drag reduction by particle addition, viscous drag reduction via surface mass injection, and interactive wall-turbulence control.

Bushnell, D.M.; Hefner, J.N.

1990-01-01T23:59:59.000Z

30

Laminar boundary layers in convective heat transport  

E-Print Network [OSTI]

We study Rayleigh-Benard convection in the high-Rayleigh-number and high-Prandtl-number regime, i.e., we consider a fluid in a container that is exposed to strong heating of the bottom and cooling of the top plate in the absence of inertia effects. While the dynamics in the bulk are characterized by a chaotic convective heat flow, the boundary layers at the horizontal container plates are essentially conducting and thus the fluid is motionless. Consequently, the average temperature exhibits a linear profile in the boundary layers. In this article, we rigorously investigate the average temperature and oscillations in the boundary layer via local bounds on the temperature field. Moreover, we deduce that the temperature profile is indeed essentially linear close to the horizontal container plates. Our results are uniform in the system parameters (e.g. the Rayleigh number) up to logarithmic correction terms. An important tool in our analysis is a new Hardy-type estimate for the convecting velocity field, which can be used to control the fluid motion in the layer. The bounds on the temperature field are derived with the help of local maximal regularity estimates for convection-diffusion equations.

Christian Seis

2012-12-12T23:59:59.000Z

31

System Identification and Active Control of a Turbulent Boundary Layer  

E-Print Network [OSTI]

An experimental investigation is made into the active control of the near-wall region of a turbulent boundary layer using a linear control scheme. System identification in the boundary layer provides optimal transfer ...

Rathnasingham, Ruben

32

Numerical Study of Freestream Waves Receptivity and Nonlinear Breakdown in Hypersonic Boundary Layer  

E-Print Network [OSTI]

Numerical Methods for Hypersonic Boundary Layer Stability.of Instability in a Hypersonic Boundary Layer. TheoreticalA. P. , Receptivity of Hypersonic Boundary Layer to Wall

Lei, Jia

2013-01-01T23:59:59.000Z

33

Boundary layer response to wind gusts  

E-Print Network [OSTI]

of the wind tunnel sir stress caused by tbe addition of the in)actors, the decision was osde to use flew visuslstion ?echniques to detsreine if it wss possible to generate s lsuinar boundary layer on the flat plate. Loup black wss suspended in light..., 8. The data reduction procedure used in this thesis follcwed pxi- maxily the procsduxes of rafax'ence 8. Velocity fluctuations were detected using the constant current technique and computed based on square wave calibration. yor the constant...

Morland, Bruce Thomas

1968-01-01T23:59:59.000Z

34

Coupled wake boundary layer model of wind-farms  

E-Print Network [OSTI]

We present and test a coupled wake boundary layer (CWBL) model that describes the distribution of the power output in a wind-farm. The model couples the traditional, industry-standard wake expansion/superposition approach with a top-down model for the overall wind-farm boundary layer structure. The wake expansion/superposition model captures the effect of turbine positioning, while the top-down portion adds the interaction between the wind-turbine wakes and the atmospheric boundary layer. Each portion of the model requires specification of a parameter that is not known a-priori. For the wake model the wake expansion coefficient is required, while the top-down model requires an effective span-wise turbine spacing within which the model's momentum balance is relevant. The wake expansion coefficient is obtained by matching the predicted mean velocity at the turbine from both approaches, while the effective span-wise turbine spacing depends on turbine positioning and thus can be determined from the wake expansion...

Stevens, Richard J A M; Meneveau, Charles

2014-01-01T23:59:59.000Z

35

Model of Trace Gas Flux in Boundary Layer  

E-Print Network [OSTI]

Mathematical model of the turbulent flux in the three-layer boundary system is presented. Turbulence is described as a presence of the nonzero vorticity. Generalized advection-diffusion-reaction equation is derived for arbitrary number components in the flux. The fluxes in the layers are objects for matching requirements on the boundaries between the layers.

I. I. Vasenev; I. S. Nurgaliev

2013-03-04T23:59:59.000Z

36

arctic boundary layer: Topics by E-print Network  

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

of many theoretical studies over the last forty years. (A Davies, Christopher 18 Tropical cyclone boundary layer shocks CERN Preprints Summary: This paper presents numerical...

37

Turbulence Structure and Wall Signature in Hypersonic Turbulent Boundary Layer  

E-Print Network [OSTI]

Turbulence Structure and Wall Signature in Hypersonic Turbulent Boundary Layer Yin-Chiu Kan , Clara and hypersonic turbulent boundary layer datasets from direct numerical simulation (DNS). Contour plots and Marusic5 and Mathis, Hutchins and Marusic16 ). In contrast to supersonic and hypersonic flow regimes

MartĂ­n, Pino

38

Trans Boundary Transport of Pollutants by Atmospheric Mineral  

E-Print Network [OSTI]

Trans Boundary Transport of Pollutants by Atmospheric Mineral Dust Y I G A L E R E L , * , U R I D, and solid constituents in the atmosphere (3-11). Uptake of pollutants by mineral dust has been shown Jerusalem, Israel The transport of anthropogenic pollution by desert dust in the Eastern Mediterranean

Einat, Aharonov

39

ARM - Field Campaign - Boundary Layer Cloud IOP  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience4AJ01)3,Cloud OD Sensor TWST Cloud OD SensorgovCampaignsBoundary

40

Lidar Investigation of Tropical Nocturnal Boundary Layer Aerosols and Cloud Macrophysics  

SciTech Connect (OSTI)

Observational evidence of two-way association between nocturnal boundary layer aerosols and cloud macrophysical properties under different meteorological conditions is reported in this paper. The study has been conducted during 2008-09 employing a high space-time resolution polarimetric micro-pulse lidar over a tropical urban station in India. Firstly, the study highlights the crucial role of boundary layer aerosols and background meteorology on the formation and structure of low-level stratiform clouds in the backdrop of different atmospheric stability conditions. Turbulent mixing induced by the wind shear at the station, which is associated with a complex terrain, is found to play a pivotal role in the formation and structural evolution of nocturnal boundary layer clouds. Secondly, it is shown that the trapping of energy in the form of outgoing terrestrial radiation by the overlying low-level clouds can enhance the aerosol mixing height associated with the nocturnal boundary layer. To substantiate this, the long-wave heating associated with cloud capping has been quantitatively estimated in an indirect way by employing an Advanced Research Weather Research and Forecasting (WRF-ARW) model version 2.2 developed by National Center for Atmospheric Research (NCAR), Colorado, USA, and supplementary data sets; and differentiated against other heating mechanisms. The present investigation as well establishes the potential of lidar remote-sensing technique in exploring some of the intriguing aspects of the cloud-environment relationship.

Manoj, M. G.; Devara, PC S.; Taraphdar, Sourav

2013-10-01T23:59:59.000Z

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


41

Distributed boundary layer suction utilizing wing tip effects  

E-Print Network [OSTI]

that this is not the case. The rotational force at the tip accounts for the suction power. Since this power is utilized to suck air from the boundary, energy is dissipated, thereby weakening the vortex strength. Providing this assumption is valid, the effect would... was done. TABLE OF CONTENTS Chapter Page INTRODUCTION OBJECTIVES AND SCOPE EXPERIMENTAL FACILITY AND PROCEDURES Wing Model . Wake Rake Boundary Layer Probe . . Multiple Tube Manometers Wind Tunnel and Related Equipment Procedures Computation...

Edwards, Jay Thomas

2012-06-07T23:59:59.000Z

42

Turbulence Structure and Wall Signature in Hypersonic Boundary Layer  

E-Print Network [OSTI]

Turbulence Structure and Wall Signature in Hypersonic Boundary Layer Yin-Chiu Kan , Beekman Izaak and low- speed features, found in subsonic experiments, are present in our supersonic and hypersonic and hypersonic regimes due to the lack of detailed flow field data, and the studies have been mostly restricted

MartĂ­n, Pino

43

OFFSHORE BOUNDARY-LAYER MODELLING H. Bergstrm1  

E-Print Network [OSTI]

OFFSHORE BOUNDARY-LAYER MODELLING H. Bergström1 and R. Barthelmie2 1) Uppsala Univ., Dept. of Earth) of the ENDOW (EfficieNt Development of Offshore Windfarms) project, where the objectives are to provide currently be incorporated into a wind farm design tool. The offshore thermal stratification climate is also

44

Turbulent heat transfer in parallel flow boundary layers with streamwise step changes in surface conditions  

SciTech Connect (OSTI)

This paper examines the convective heat/mass transfer behavior of a turbulent boundary layer with parallel streamlines. The most notable example of such flow is an atmospheric boundary layer with a steady mean wind in the absence of topography. The classic, two-dimensional problem involves the surface boundary condition of a finite-length step change in temperature/concentration in the streamwise direction of an atmospheric flow. In the literature on geophysical evapotranspiration, this problem is known as Sutton's problem (cf. Sutton, 1934, and Brutsaert, 1984). This flow situation is equally applicable to heat/mass transfer in solar ponds, ground solar collectors, and heated roadways, as examples. The present note revisits the Sutton problem, with the can Driest eddy diffusivity model, and expands the types of boundary conditions that are examined to include surface changes in temperature/concentration and fluxes. The parallel streamline condition allows for Graetz-type solutions, with boundary conditions at the surface and in the far flow field. The predicted results are presented as a series of power law correlations of the relevant nondimensional parameters.

Lindberg, W.R.; Lee, R.C.; Smathers, L.B. (Univ. of Wyoming, Laramie (United States))

1989-11-01T23:59:59.000Z

45

Energy Conservation and Second-Order Statistics in Stably Stratified Turbulent Boundary Layers  

E-Print Network [OSTI]

We address the dynamical and statistical description of stably stratified turbulent boundary layers with the important example of the atmospheric boundary layer with a stable temperature stratification in mind. Traditional approaches to this problem, based on the profiles of mean quantities, velocity second-order correlations, and dimensional estimates of the turbulent thermal flux run into a well known difficulty, predicting the suppression of turbulence at a small critical value of the Richardson number, in contradiction with observations. Phenomenological attempts to overcome this problem suffer from various theoretical inconsistencies. Here we present an approach taking into full account all the second-order statistics, which allows us to respect the conservation of total mechanical energy. The analysis culminates in an analytic solution of the profiles of all mean quantities and all second-order correlations removing the unphysical predictions of previous theories. We propose that the approach taken here is sufficient to describe the lower parts of the atmospheric boundary layer, as long as the Richardson number does not exceed an order of unity. For much higher Richardson numbers the physics may change qualitatively, requiring careful consideration of the potential Kelvin-Helmoholtz waves and their interaction with the vortical turbulence.

Victor S. L'vov; Itamar Procaccia; Oleksii Rudenko

2007-05-01T23:59:59.000Z

46

Examining A Hypersonic Turbulent Boundary Layer at Low Reynolds Number  

E-Print Network [OSTI]

z spanwise direction, m Greek Symbols boundary layer thickness, m displacement thickness, m ratio of speci c heats hotwire recovery ratio dynamic viscosity, Pa s density, kg=m3 hotwire overheat ratio, Twire=Tt momentum thickness, m... direct numerical simulation LDV laser doppler velocimetry LES large eddy simulation MTV molecular tagging velocimetry OHR overheat ratio (see ) PIV particle image velocimetry PLIF planar laser induced uorescence RANS Reynolds averaged Navier...

Semper, Michael Thomas

2013-05-15T23:59:59.000Z

47

Long-term Observations of the Convective Boundary Layer Using Insect Radar Returns at the SGP ARM Climate Research Facility  

SciTech Connect (OSTI)

A long-term study of the turbulent structure of the convective boundary layer (CBL) at the U.S. Department of Energy Atmospheric Radiation Measurement Program (ARM) Southern Great Plains (SGP) Climate Research Facility is presented. Doppler velocity measurements from insects occupying the lowest 2 km of the boundary layer during summer months are used to map the vertical velocity component in the CBL. The observations cover four summer periods (2004-08) and are classified into cloudy and clear boundary layer conditions. Profiles of vertical velocity variance, skewness, and mass flux are estimated to study the daytime evolution of the convective boundary layer during these conditions. A conditional sampling method is applied to the original Doppler velocity dataset to extract coherent vertical velocity structures and to examine plume dimension and contribution to the turbulent transport. Overall, the derived turbulent statistics are consistent with previous aircraft and lidar observations. The observations provide unique insight into the daytime evolution of the convective boundary layer and the role of increased cloudiness in the turbulent budget of the subcloud layer. Coherent structures (plumes-thermals) are found to be responsible for more than 80% of the total turbulent transport resolved by the cloud radar system. The extended dataset is suitable for evaluating boundary layer parameterizations and testing large-eddy simulations (LESs) for a variety of surface and cloud conditions.

Chandra, A S; Kollias, P; Giangrande, S E; Klein, S A

2009-08-20T23:59:59.000Z

48

Multi-dimensional Longwave Forcing of Boundary Layer Cloud Systems  

SciTech Connect (OSTI)

The importance of multi-dimensional (MD) longwave radiative effects on cloud dynamics is evaluated in a large eddy simulation (LES) framework employing multi-dimensional radiative transfer (Spherical Harmonics Discrete Ordinate Method —SHDOM). Simulations are performed for a case of unbroken, marine boundary layer stratocumulus and a broken field of trade cumulus. “Snapshot” calculations of MD and IPA (independent pixel approximation —1D) radiative transfer applied to LES cloud fields show that the total radiative forcing changes only slightly, although the MD effects significantly modify the spatial structure of the radiative forcing. Simulations of each cloud type employing MD and IPA radiative transfer, however, differ little. For the solid cloud case, relative to using IPA, the MD simulation exhibits a slight reduction in entrainment rate and boundary layer TKE relative to the IPA simulation. This reduction is consistent with both the slight decrease in net radiative forcing and a negative correlation between local vertical velocity and radiative forcing, which implies a damping of boundary layer eddies. Snapshot calculations of the broken cloud case suggest a slight increase in radiative cooling, though few systematic differences are noted in the interactive simulations. We attribute this result to the fact that radiative cooling is a relatively minor contribution to the total energetics. For the cloud systems in this study, the use of IPA longwave radiative transfer is sufficiently accurate to capture the dynamical behavior of BL clouds. Further investigations are required in order to generalize this conclusion for other cloud types and longer time integrations. 1

Mechem, David B.; Kogan, Y. L.; Ovtchinnikov, Mikhail; Davis, Anthony B; Evans, K. F.; Ellingson, Robert G.

2008-12-20T23:59:59.000Z

49

Improving Subtropical Boundary Layer Cloudiness in the 2011 NCEP GFS  

SciTech Connect (OSTI)

The current operational version of National Centers for Environmental Prediction (NCEP) Global Forecasting System (GFS) shows significant low cloud bias. These biases also appear in the Coupled Forecast System (CFS), which is developed from the GFS. These low cloud biases degrade seasonal and longer climate forecasts, particularly of short-wave cloud radiative forcing, and affect predicted sea surface temperature. Reducing this bias in the GFS will aid the development of future CFS versions and contributes to NCEP's goal of unified weather and climate modelling. Changes are made to the shallow convection and planetary boundary layer parameterisations to make them more consistent with current knowledge of these processes and to reduce the low cloud bias. These changes are tested in a single-column version of GFS and in global simulations with GFS coupled to a dynamical ocean model. In the single-column model, we focus on changing parameters that set the following: the strength of shallow cumulus lateral entrainment, the conversion of updraught liquid water to precipitation and grid-scale condensate, shallow cumulus cloud top, and the effect of shallow convection in stratocumulus environments. Results show that these changes improve the single-column simulations when compared to large eddy simulations, in particular through decreasing the precipitation efficiency of boundary layer clouds. These changes, combined with a few other model improvements, also reduce boundary layer cloud and albedo biases in global coupled simulations.

Fletcher, J. K.; Bretherton, Christopher S.; Xiao, Heng; Sun, Ruiyu N.; Han, J.

2014-09-23T23:59:59.000Z

50

Wind profile above the surface boundary layer S.-E. Gryning (1), E. Batchvarova (2) and B. Brmmer (3)  

E-Print Network [OSTI]

Wind profile above the surface boundary layer S.-E. Gryning (1), E. Batchvarova (2) and B. BrĂŒmmer in predictions of the wind profile in the lowest hundreds me- ters of the atmosphere, being connected to the general increase in height of structures such as bridges, high houses and wind turbines. The hub height

51

BOUNDARY LAYER (BL) THERMAL EDDIES OVER A PINE FOREST FROM CARES 2010  

E-Print Network [OSTI]

BOUNDARY LAYER (BL) THERMAL EDDIES OVER A PINE FOREST FROM CARES 2010 Gunnar Senum and Stephen are three thermal eddies, about 250 meters wide, in the boundary layer. These thermal eddies are formed from the solar heating of the surface and help to form the boundary layer. The eddy updrafts are transporting

52

Transition in Hypersonic Boundary Layers: Role of Dilatational Waves  

E-Print Network [OSTI]

Transition and turbulence production in a hypersonic boundary layer is investigated in a Mach 6 quiet wind tunnel using Rayleigh-scattering visualization, fast-response pressure measurements, and particle image velocimetry. It is found that the second instability acoustic mode is the key modulator of the transition process. The second mode experiences a rapid growth and a very fast annihilation due to the effect of bulk viscosity. The second mode interacts strongly with the first vorticity mode to directly promote a fast growth of the latter and leads to immediate transition to turbulence.

Zhu, Yiding; Yuan, Huijing; Wu, Jiezhi; Chen, Shiyi; Lee, Cunbiao; Gad-el-Hak, Mohamed

2015-01-01T23:59:59.000Z

53

EART 265 Lecture Notes: Boundary Layers We're interested here mainly in boundary layers relevant to planets, i.e. those of planetary atmo-  

E-Print Network [OSTI]

of the bounding surface. Note that the vertical shear caused by the surface generates turbulence, whichEART 265 Lecture Notes: Boundary Layers We're interested here mainly in boundary layers relevant and the surface, thus mediating all interactions between the two. If we look back at the Navier-Stokes equations

Nimmo, Francis

54

Laminar-turbulent separatrix in a boundary layer flow  

E-Print Network [OSTI]

The transitional boundary layer flow over a flat plate is investigated. The boundary layer flow is known to develop unstable Tollmien-Schlichting waves above a critical value of the Reynolds number. However, it is also known that this transition can be observed for sub-critical Reynolds numbers. In that case, the basin of attraction of the laminar state coexists with the sustained turbulence. In this article, the trajectory on the separatrix between these two states is simulated. The state on the separatrix is independent from the initial condition and is dynamically connected to both the laminar flow and the turbulence. Such an edge state provides information regarding the basic features of the transitional flow. The solution takes the form of a low speed streak, flanked by two quasi-streamwise sinuous vortices. The shape of the streaks is close to that simulated with the linear optimal perturbation method. This solution is compared to existing results concerning streak breakdown. The simulations are realize...

Biau, Damien

2013-01-01T23:59:59.000Z

55

Predictive Inner-Outer Model for Turbulent Boundary Layers Applied to Hypersonic DNS Data  

E-Print Network [OSTI]

Predictive Inner-Outer Model for Turbulent Boundary Layers Applied to Hypersonic DNS Data Clara numerical simulation (DNS) data of supersonic and hypersonic turbulent boundaries with Mach 3 and Mach 7, and Martin12­14 on DNS of hypersonic turbulent boundary layers demonstrates the existence of large scale

MartĂ­n, Pino

56

Friction of a slider on a granular layer: Nonmonotonic thickness dependence and effect of boundary conditions  

E-Print Network [OSTI]

Friction of a slider on a granular layer: Nonmonotonic thickness dependence and effect of boundary the effective friction encountered by a mass sliding on a granular layer as a function of bed thickness and boundary roughness conditions. The observed friction has minima for a small number of layers before

Kudrolli, Arshad

57

Further development and testing of a second-order bulk boundary layer model. Master's thesis  

SciTech Connect (OSTI)

A one-layer bulk boundary layer model is developed. The model predicts the mixed layer values of the potential temperature, mixing ratio, and u- and v-momentum. The model also predicts the depth of the boundary layer and the vertically integrated turbulence kinetic energy (TKE). The TKE is determined using a second-order closure that relates the rate of dissipation to the TKE. The fractional area covered by rising motion sigma and the entrainment rate (E) are diagnostically determined. The model is used to study the clear convective boundary layer (CBL) using data from the Wangara, Australia boundary layer experiment. The Wangara data is also used as an observation base to validate model results. A further study is accomplished by simulating the planetary boundary layer (PBL) over an ocean surface. This study is designed to find the steady-state solutions of the prognostic variable.

Krasner, R.D.

1993-05-03T23:59:59.000Z

58

Planetary boundary layer depth in Global climate models induced biases in surface climatology  

E-Print Network [OSTI]

The Earth has warmed in the last century with the most rapid warming occurring near the surface in the arctic. This enhanced surface warming in the Arctic is partly because the extra heat is trapped in a thin layer of air near the surface due to the persistent stable-stratification found in this region. The warming of the surface air due to the extra heat depends upon the amount of turbulent mixing in the atmosphere, which is described by the depth of the atmospheric boundary layer (ABL). In this way the depth of the ABL determines the effective response of the surface air temperature to perturbations in the climate forcing. The ABL depth can vary from tens of meters to a few kilometers which presents a challenge for global climate models which cannot resolve the shallower layers. Here we show that the uncertainties in the depth of the ABL can explain up to 60 percent of the difference between the simulated and observed surface air temperature trends and 50 percent of the difference in temperature variability...

Davy, Richard

2014-01-01T23:59:59.000Z

59

Simulation of Hypersonic Shock Wave/Boundary Layer Interaction Using High Order WENO Scheme  

E-Print Network [OSTI]

Simulation of Hypersonic Shock Wave/Boundary Layer Interaction Using High Order WENO Scheme Yiqing for predicting hypersonic shock wave/boundary layer interaction. The implicit time marching method number of 1.09 Ă? 105 /ft. 1 Introduction Hypersonic aerothermodynamics is one of the most challenging

Zha, Gecheng

60

Study of Emission TurbulenceRadiation Interaction in Hypersonic Boundary Layers  

E-Print Network [OSTI]

Study of Emission Turbulence­Radiation Interaction in Hypersonic Boundary Layers L. Duan and M. P of emission turbulence­radiation interaction in hypersonic turbulent boundary layers, representative interaction between turbulence and emission at the hypersonic environment under investigation. An explanation

MartĂ­n, Pino

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


61

Assessment of TurbulenceChemistry Interaction in Hypersonic Turbulent Boundary Layers  

E-Print Network [OSTI]

Assessment of Turbulence­Chemistry Interaction in Hypersonic Turbulent Boundary Layers L. Duan of the turbulence­chemistry interaction are performed in hypersonic turbulent boundary layers using direct numerical simulation flowfields under typical hypersonic conditions representative of blunt-body and slender- body

MartĂ­n, Pino

62

Study of turbulence-chemistry interaction in hypersonic turbulent boundary layers  

E-Print Network [OSTI]

Study of turbulence-chemistry interaction in hypersonic turbulent boundary layers Lian Duan and M of the turbulence-chemistry interaction (TCI) are performed in hypersonic tur- bulent boundary layers using direct numerical simulation (DNS) flow fields under typical hypersonic conditions representative of blunt

MartĂ­n, Pino

63

Intercomparison of cloud model simulations of Arctic mixed-phase boundary layer clouds observed during  

E-Print Network [OSTI]

/crystal concentration also suggests the need for improved understanding of ice nucleation and its parameterizationIntercomparison of cloud model simulations of Arctic mixed-phase boundary layer clouds observed is presented. This case study is based on observations of a persistent mixed-phase boundary layer cloud

Zuidema, Paquita

64

Direct injection of ionospheric O sup + into the dayside low latitude boundary layer  

SciTech Connect (OSTI)

Observations from the AMPTE/Charge Composition Explorer (AMPTE/CCE) indicate the presence of two distinct O{sup +} populations in the dayside subsolar low latitude boundary layer during some periods of northward Interplanetary Magnetic Field (IMF). The first population is O{sup +} convected into the boundary layer from the outer magnetosphere and has been reported previously. It is suggested here that the new, second, O{sup +} population is injected into the dayside boundary layer directly from the high latitude ionosphere. This second population can have a significant density and distinct characteristics such as field-aligned flow relative to boundary layer H{sup +} that modify both the plasma composition and dynamics in the low latitude boundary layer. {copyright} American Geophysical Union 1989

Fuselier, S.A.; Klumpar, D.M.; Peterson, W.K.; Shelley, E.G. (Lockheed Palo Alto Research Laboratory, Palo Alto, California (US))

1989-10-01T23:59:59.000Z

65

Interaction between surface and atmosphere in a convective boundary layer /  

E-Print Network [OSTI]

heat, and thermal conductivity of the ground and grid sizegrid was stretched uniformly to 0.1 m resolution. The heatheat flux) are friction velocity and convective velocity respectively. The grid

Garai, Anirban

2013-01-01T23:59:59.000Z

66

Interaction between surface and atmosphere in a convective boundary layer /  

E-Print Network [OSTI]

II.4) to measure vertical profiles of wind speed, direction,a larger vertical gradient of horizontal wind-speed in theintense vertical mixing, resulting in constant wind speed,

Garai, Anirban

2013-01-01T23:59:59.000Z

67

ARM - Field Campaign - 2013 Lower Atmospheric Boundary Layer Experiment  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience4AJ01)3, 2010September 30,JuneMay 15,October 6,2 NEAQS (New7

68

Interaction between surface and atmosphere in a convective boundary layer /  

E-Print Network [OSTI]

resulting in constant wind, and potential temperature andatmospheric wind speed, direction and potential temperatureatmospheric profiles (wind speed, potential temperature),

Garai, Anirban

2013-01-01T23:59:59.000Z

69

EXPERIMENTAL STUDY OF COMBUSTION IN A TURBULENT BOUNDARY LAYER  

E-Print Network [OSTI]

evaporation, but the thermophoretic migration of particlesboundary layer due to thermophoretic motion and evaporation

Cheng, R.K.

2011-01-01T23:59:59.000Z

70

E-Print Network 3.0 - atmospheric layers Sample Search Results  

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

layer model Summary: an atmosphere, using the layer model, which incorporates the greenhouse effect of the atmosphere. For now... ,atm + Idown,atm Iup, ground If radiation up and...

71

DIFFUSION OF A CHEMICAL SPECIES THROUGH A VISCOUS BOUNDARY LAYER  

E-Print Network [OSTI]

2.3 Evaluation of a Coal Gasification Atmosphere. . -iv-a highly cor- rosive coal gasification mixture. It is shown2.3 Evaluation of a Coal Gasification Atmosphere The purpose

Keller, J.

2011-01-01T23:59:59.000Z

72

Boundary-Layer Stability and Transition on a Flared Cone in a Mach 6 Quiet Wind Tunnel  

E-Print Network [OSTI]

A key remaining challenge in the design of hypersonic vehicles is the incomplete understanding of the process of boundary-layer transition. Turbulent heating rates are substantially higher than those for a laminar boundary layer, and large...

Hofferth, Jerrod William

2013-05-15T23:59:59.000Z

73

Stability Analysis for a Saline Boundary Layer Formed by Uniform Up ow Using Finite Elements  

E-Print Network [OSTI]

density in the deeper underground and high salt water density at the boundary layer), gravitation plays and Darcy's law. In this report we #12;rst give an overview of semi-analytical methods to analyse

Eindhoven, Technische Universiteit

74

Nonlinear equilibration of baroclinic eddies : the role of boundary layer processes and seasonal forcing  

E-Print Network [OSTI]

In this thesis, the influence of boundary layer processes and seasonal forcing on baroclinic eddy equilibration is studied to understand how the baroclinic adjustment is modified when taking into account these two factors. ...

Zhang, Yang, Ph. D. Massachusetts Institute of Technology

2009-01-01T23:59:59.000Z

75

Observations of Turbulence in the Ocean Surface Boundary Layer: Energetics and Transport  

E-Print Network [OSTI]

Observations of turbulent kinetic energy (TKE) dynamics in the ocean surface boundary layer are presented here and compared with results from previous observational, numerical, and analytic studies. As in previous studies, ...

Gerbi, Gregory P.

76

Advances in the visualization and analysis of boundary layer flow in swimming fish  

E-Print Network [OSTI]

In biology, the importance of fluid drag, diffusion, and heat transfer both internally and externally, suggest the boundary layer as an important subject of investigation, however, the complexities of biological systems ...

Anderson, Erik J

2005-01-01T23:59:59.000Z

77

Design of a model propulsor for a boundary layer ingesting aircraft  

E-Print Network [OSTI]

This thesis presents contributions to the analysis and design of propulsion simulators for 1:11 and 1:4 scale model wind tunnel investigations of an advanced civil transport aircraft with boundary layer ingestion (BLI). ...

Grasch, Adam D. (Adam Davis)

2013-01-01T23:59:59.000Z

78

Turbulent combined wave-current boundary layer model for application in coastal waters  

E-Print Network [OSTI]

Accurately predicting transport processes, including sediment transport, in the coastal environment is impossible without correct current velocity and shear stress information. A combined wave-current boundary layer theory ...

Humbyrd, Chelsea Joy

2012-01-01T23:59:59.000Z

79

Observations of turbulent fluxes and turbulence dynamics in the ocean surface boundary layer  

E-Print Network [OSTI]

This study presents observations of turbulence dynamics made during the low winds portion of the Coupled Boundary Layers and Air-Sea Transfer experiment (CBLAST-Low). Observations were made of turbulent fluxes, turbulent ...

Gerbi, Gregory Peter

2008-01-01T23:59:59.000Z

80

The effect of periodic-unsteady wakes, curvature, and pressure gradient on boundary-layer transition  

E-Print Network [OSTI]

Boundary-layer transition on a concave curved plate has been investigated with and without periodic-unsteady inlet flow at zero and negative pressure gradients. The periodicunsteady wakes were created using a rotating squirrel-cage type wake...

Radke, Robert Edward

1994-01-01T23:59:59.000Z

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


81

Transforming the representation of the boundary layer and low clouds for high-resolution regional climate modeling: Final report  

SciTech Connect (OSTI)

Stratocumulus and shallow cumulus clouds in subtropical oceanic regions (e.g., Southeast Pacific) cover thousands of square kilometers and play a key role in regulating global climate (e.g., Klein and Hartmann, 1993). Numerical modeling is an essential tool to study these clouds in regional and global systems, but the current generation of climate and weather models has difficulties in representing them in a realistic way (e.g., Siebesma et al., 2004; Stevens et al., 2007; Teixeira et al., 2011). While numerical models resolve the large-scale flow, subgrid-scale parameterizations are needed to estimate small-scale properties (e.g. boundary layer turbulence and convection, clouds, radiation), which have significant influence on the resolved scale due to the complex nonlinear nature of the atmosphere. To represent the contribution of these fine-scale processes to the resolved scale, climate models use various parameterizations, which are the main pieces in the model that contribute to the low clouds dynamics and therefore are the major sources of errors or approximations in their representation. In this project, we aim to 1) improve our understanding of the physical processes in thermal circulation and cloud formation, 2) examine the performance and sensitivity of various parameterizations in the regional weather model (Weather Research and Forecasting model; WRF), and 3) develop, implement, and evaluate the advanced boundary layer parameterization in the regional model to better represent stratocumulus, shallow cumulus, and their transition. Thus, this project includes three major corresponding studies. We find that the mean diurnal cycle is sensitive to model domain in ways that reveal the existence of different contributions originating from the Southeast Pacific land-masses. The experiments suggest that diurnal variations in circulations and thermal structures over this region are influenced by convection over the Peruvian sector of the Andes cordillera, while the mostly dry mountain-breeze circulations force an additional component that results in semi-diurnal variations near the coast. A series of numerical tests, however, reveal sensitivity of the simulations to the choice of vertical grid, limiting the possibility of solid quantitative statements on the amplitudes and phases of the diurnal and semidiurnal components across the domain. According to our experiments, the Mellor-Yamada-Nakanishi-Niino (MYNN) boundary layer scheme and the WSM6 microphysics scheme is the combination of schemes that performs best. For that combination, mean cloud cover, liquid water path, and cloud depth are fairly wellsimulated, while mean cloud top height remains too low in comparison to observations. Both microphysics and boundary layer schemes contribute to the spread in liquid water path and cloud depth, although the microphysics contribution is slightly more prominent. Boundary layer schemes are the primary contributors to cloud top height, degree of adiabaticity, and cloud cover. Cloud top height is closely related to surface fluxes and boundary layer structure. Thus, our study infers that an appropriate tuning of cloud top height would likely improve the low-cloud representation in the model. Finally, we show that entrainment governs the degree of adiabaticity, while boundary layer decoupling is a control on cloud cover. In the intercomparison study using WRF single-column model experiments, most parameterizations show a poor agreement of the vertical boundary layer structure when compared with large-eddy simulation models. We also implement a new Total-Energy/Mass- Flux boundary layer scheme into the WRF model and evaluate its ability to simulate both stratocumulus and shallow cumulus clouds. Result comparisons against large-eddy simulation show that this advanced parameterization based on the new Eddy-Diffusivity/Mass-Flux approach provides a better performance than other boundary layer parameterizations.

Huang, Hsin-Yuan; Hall, Alex

2013-07-24T23:59:59.000Z

82

Shipboard measurements of the cloud-capped marine boundary layer during FIRE/ASTEX  

SciTech Connect (OSTI)

Results are reported on measurements of the cloud-capped marine boundary layer during FIRE/ASTEX. A method was developed from the ASTEX dataset for measuring profiles of liquid water content, droplet size and concentration from cloud radar/microwave radiometer data in marine boundary layer clouds. Profiles were also determined from the first three moments of the Doppler spectrum measured in drizzle with the ETL cloud radar during ASTEX.

NONE

1997-09-01T23:59:59.000Z

83

Effect of a surface boundary layer on an intensifying, downward-propagating vortex  

E-Print Network [OSTI]

EFFECT OF A SURFACE BOUNDARY LAYER ON AN INTENSIFYING, DOWNWARD-PROPAGATING VORTEX A Thesis by VINCENT TUNSTALL WOOD Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1977 Major Subject: Meteorology EFFECT OF A SURFACE BOUNDARY LAYER ON AN INTENSIFYING, DOWNWARD-PROPAGATING VORTEX A Thesis by VINCENT TUNSTALL WOOD Approved as to style and content by: (Chairman of Committee) (Head of Department...

Wood, Vincent Tunstall

2012-06-07T23:59:59.000Z

84

Influence of surface heating on the boundary layer stability of flows with favorable pressure gradients  

E-Print Network [OSTI]

INFLUENCE OF SURFACE HEATING ON THE BOUNDARY LAYER STABILITY OF FLOWS WITH FAVORABI E PRESSURE GRADIENTS A Thesis by DAVID BRIAN LANDRUM Submitted to the Graduate College of Texas AAM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 1986 Major Subject: Aerospace Engineering INFLUENCE OF SURFACE HEATING ON THE BOUNDARY LAYER STABILITY OF FLOWS WITH FAVORABLE PRESSURE GRADIENTS A Thesis by DAVID BRIAN LANDRUM Approved as to style and content...

Landrum, David Brian

2012-06-07T23:59:59.000Z

85

atmospheric convective boundary: Topics by E-print Network  

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

convective conditions is found to be primarily due to variations in mixed layer wind speed. Low-level winds thus play the major role in regulating the ability of thermals to...

86

Role of Amorphous Boundary Layer in Enhancing Ionic Conductivity of Lithium–lanthanum–titanate Electrolyte  

SciTech Connect (OSTI)

The low ionic conductivity is a bottleneck of the inorganic solid state electrolyte used for lithium ion battery. In ceramic electrolytes, grain boundary usually dominates the total conductivity. In order to improve the grain boundary effect, an amorphous silica layer is introduced into grain boundary of ceramic electrolytes based on lithium-lanthanum-titanate, as evidenced by electron microscopy. The results showed that the total ionic conductivity could be to be enhanced over 1 x 10{sup -4} S/cm at room temperature. The reasons can be attributed to removing the anisotropy of outer-shell of grains, supplement of lithium ions in various sites in grain boundary and close bindings among grains by the amorphous boundary layer among grains.

Mei, A.; Wang, X.; Lana, J.-L.; Fenga, Y.-C.; Genga, H.-X.; Lina, Y.-H.; Nana, C.-W.

2010-03-01T23:59:59.000Z

87

Characterizing the Separation and Reattachment of Suction Surface Boundary Layer in Low Pressure Turbine Using Massively Parallel Large Eddy Simulations  

E-Print Network [OSTI]

cient, p p1 1 2 U21 Cax Axial chord H12 Form factor R11 Correlation coe cient Tu Turbulence intensity Ue Boundary layer edge velocity U1 Freestream velocity 1 Displacement thickness of a boundary layer 2 Momentum thickness of a boundary...

Jagannathan, Shriram

2012-02-14T23:59:59.000Z

88

Combustion-turbulence interaction in the turbulent boundary layer over a hot surface  

SciTech Connect (OSTI)

The turbulence-combustion interaction in a reacting turbulent boundary layer over a heated flat plate was studied. Ethylene/air mixture with equivalence ratio of 0.35 was used. The free stream velocity was 10.5 m/s and the wall temperature was 1250/sup 0/K. Combustion structures visualization was provided by high-speed schlieren photographs. Fluid density statistics were deduced from Rayleigh scattering intensity measurements. A single-component laser Doppler velocimetry system was used to obtain mean and root-mean-square velocity distributions, the Reynolds stress, the streamwise and the cross-stream turbulent kinetic energy diffusion, and the production of turbulent kinetic energy by Reynolds stress. The combustion process was dominated by large-scale turbulent structures of the boundary layer. Combustion causes expansion of the boundary layer. No overall self-similarity is observed in either the velocity or the density profiles. Velocity fluctuations were increased in part of the boundary layer and the Reynolds stress was reduced. The turbulent kinetic energy diffusion pattern was changed significantly and a modification of the boundary layer assumption will be needed when dealing with this problem analytically. 11 figures, 1 table.

Ng, T.T.; Cheng, R.K.; Robben, F.; Talbot, L.

1982-01-01T23:59:59.000Z

89

Vertical Velocities in Continental Boundary Layer Stratocumulus Clouds  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism inS-4500IIVasudha Patri MechanicalofVehicles -winsVenueVertical

90

Temporal variability of the trade wind inversion: Measured with a boundary layer vertical profiler. Master's thesis  

SciTech Connect (OSTI)

This study uses Hawaiian Rainband Project (HaRP) data, from the summer of 1991, to show a boundary layer wind profiler can be used to measure the trade wind inversion. An algorithm has been developed for the profiler that objectively measures the depth of the moist oceanic boundary layer. The Hilo inversion, measured by radiosonde, is highly correlated with the moist oceanic boundary layer measured by the profiler at Paradise Park. The inversion height on windward Hawaii is typically 2253 + or - 514 m. The inversion height varies not only on a daily basis, but on less than an hourly basis. It has a diurnal, as well as a three to four day cycle. There appears to be no consistent relationship between inversion height and precipitation. Currently, this profiler is capable of making high frequency (12 minute) measurements of the inversion base variation, as well as other features.

Grindinger, C.M.

1992-05-01T23:59:59.000Z

91

Effects of passive porous walls on the first Mack mode instability of hypersonic boundary layers over a sharp cone.  

E-Print Network [OSTI]

??Passive porous coatings have been proposed in literature as a means of delaying transition to turbulence in hypersonic boundary layers. The nonlinear stability of hypersonic… (more)

Michael, Vipin George

2013-01-01T23:59:59.000Z

92

Mars Exploration Rover (MER) Panoramic Camera (Pancam) Twilight Image Analysis for Determination of Planetary Boundary Layer and Dust Particle Size Parameters  

E-Print Network [OSTI]

to take surface-based measurements to offer support for dust and boundary layer measurements made from remote sensors (Lemmon et al., 2004a). Mars has different atmospheric characteristics from those on Earth. For example, the solar constant for Mars... is approximately 44% of the value for Earth (varying by approximately 20%), and the temperature ranges on Mars (- 125?C to +25?C) slightly ____________ This thesis follows the style of the Journal of Geophysical Research. 2 overlap those on Earth (- 80?C...

Grounds, Stephanie Beth

2012-02-14T23:59:59.000Z

93

Behavior of Turbulent Structures within a Mach 5 Mechanically Distorted Boundary Layer  

E-Print Network [OSTI]

field of incompressible boundary layer, taken from Adrian et al. (2000). ............................................................................... 138 Figure 6.15 Schematic of an individual hairpin vortex, describing the sweep and ejection... hairpin vortex, identifying the motions contributing to sweeps and ejections ....................................................................................... 235 Figure 7.46 Illustrations of the possible mechanisms contributing to the reduced...

Peltier, Scott Jacob

2013-08-05T23:59:59.000Z

94

Acoustic Properties of Porous Coatings for Hypersonic Boundary-Layer Control  

E-Print Network [OSTI]

Acoustic Properties of Porous Coatings for Hypersonic Boundary-Layer Control Guillaume A. BrĂšs for hypersonic laminar flow control. The reflection coefficient, characterizing the ratio of the reflected wave of incidence, for coatings of different porosities, at various acoustic Reynolds numbers relevant to hypersonic

Dabiri, John O.

95

Effect of Finite-rate Chemical Reactions on Turbulence in Hypersonic Turbulent Boundary Layers  

E-Print Network [OSTI]

Effect of Finite-rate Chemical Reactions on Turbulence in Hypersonic Turbulent Boundary Layers Lian on future air-breathing hypersonic cruise vehicles will be turbulent and chemically reacting. To aid the design of such vehicles, a greater understanding of turbulent hypersonic flows is needed. Although

MartĂ­n, Pino

96

Direct Numerical Simulation of a Hypersonic Turbulent Boundary Layer on a Large Domain  

E-Print Network [OSTI]

Direct Numerical Simulation of a Hypersonic Turbulent Boundary Layer on a Large Domain Stephan Priebe , M. Pino MartÂŽin The direct numerical simulation (DNS) of a spatially-developing hypersonic There are few studies of hypersonic flows at Mach number greater than 5 and few involve the measurement of mean

MartĂ­n, Pino

97

EUROPEAN CONFERENCE FOR AEROSPACE SCIENCES Shock Wave / Boundary Layer Interactions in Hypersonic  

E-Print Network [OSTI]

and a combina- tion of laminar and turbulent (transitional) computations as well as preliminary 3D simulations the impact on the shock / boundary layer interaction and on the size of the shock induced separation. Laminar have been conducted and show the experimental shock-tunnel results to be influenced by transition and 3

98

Flowfield and wall pressure characteristics downstream of a boundary layer suction device.  

E-Print Network [OSTI]

Flowfield and wall pressure characteristics downstream of a boundary layer suction device. Meagan A-dimensional slit can significantly reduce the fluctuating wall pressure immediately downstream of the suction slit momentum regions of the flow with the wall at the downstream edge of the suction slit. The third region

Tinney, Charles E.

99

ESTIMATING BEDROCK AND SURFACE LAYER BOUNDARIES AND CONFIDENCE INTERVALS IN ICE SHEET RADAR IMAGERY USING MCMC  

E-Print Network [OSTI]

ESTIMATING BEDROCK AND SURFACE LAYER BOUNDARIES AND CONFIDENCE INTERVALS IN ICE SHEET RADAR IMAGERY and Computing Indiana University Bloomington, Indiana USA ABSTRACT Climate models that predict polar ice sheet behavior require accurate measurements of the bedrock-ice and ice-air bound- aries in ground

Menczer, Filippo

100

Shock-like structures in the tropical cyclone boundary layer Gabriel J. Williams,1  

E-Print Network [OSTI]

the horizontal and vertical velocity data shown by the blue curves in Figure 1. The extreme horizontal wind m in the northeast sector. Since these extreme structures in the boundary layer wind field occur produces a shock-like structure in the radial wind, i.e., near the radius of maximum tangential wind

Schubert, Wayne H.

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


101

Prospects for Simulating Macromolecular Surfactant Chemistry at the Ocean-Atmosphere Boundary  

SciTech Connect (OSTI)

Biogenic lipids and polymers are surveyed for their ability to adsorb at the water-air interfaces associated with bubbles, marine microlayers and particles in the overlying boundary layer. Representative ocean biogeochemical regimes are defined in order to estimate local concentrations for the major macromolecular classes. Surfactant equilibria and maximum excess are then derived based on a network of model compounds. Relative local coverage and upward mass transport follow directly, and specific chemical structures can be placed into regional rank order. Lipids and denatured protein-like polymers dominate at the selected locations. The assigned monolayer phase states are variable, whether assessed along bubbles or at the atmospheric spray droplet perimeter. Since oceanic film compositions prove to be irregular, effects on gas and organic transfer are expected to exhibit geographic dependence as well. Moreover, the core arguments extend across the sea-air interface into aerosol-cloud systems. Fundamental nascent chemical properties including mass to carbon ratio and density depend strongly on the geochemical state of source waters. High surface pressures may suppress the Kelvin effect, and marine organic hygroscopicities are almost entirely unconstrained. While bubble adsorption provides a well-known means for transporting lipidic or proteinaceous material into sea spray, the same cannot be said of polysaccharides. Carbohydrates tend to be strongly hydrophilic so that their excess carbon mass is low despite stacked polymeric geometries. Since sugars are abundant in the marine aerosol, gel-based mechanisms may be required to achieve uplift. Uncertainties in the surfactant logic distill to a global scale dearth of information regarding two dimensional kinetics and equilibria. Nonetheless simulations are recommended, to initiate the process of systems level quantification.

Elliott, S.; Burrows, Susannah M.; Deal, C.; Liu, Xiaohong; Long, M.; Ogunro, O.; Russell, Lynn M.; Wingenter, O.

2014-06-09T23:59:59.000Z

102

Clouds, Precipitation, and Marine Boundary Layer Structure during the MAGIC Field Campaign  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

The recent ship-based MAGIC (Marine ARM GCSS Pacific Cross-Section Intercomparison (GPCI) Investigation of Clouds) field campaign with the marine-capable Second ARM Mobile Facility (AMF2) deployed on the Horizon Lines cargo container M/V Spirit provided nearly 200 days of intraseasonal high-resolution observations of clouds, precipitation, and marine boundary layer (MBL) structure on multiple legs between Los Angeles, California, and Honolulu, Hawaii. During the deployment, MBL clouds exhibited a much higher frequency of occurrence than other cloud types and occurred more often in the warm season than in the cold season. MBL clouds demonstrated a propensity to produce precipitation, which often evaporated before reaching the ocean surface. The formation of stratocumulus is strongly correlated to a shallow MBL with a strong inversion and a weak transition, while cumulus formation is associated with a much weaker inversion and stronger transition. The estimated inversion strength is shown to depend seasonally on the potential temperature at 700 hPa. The location of the commencement of systematic MBL decoupling always occurred eastward of the locations of cloud breakup, and the systematic decoupling showed a strong moisture stratification. The entrainment of the dry warm air above the inversion appears to be the dominant factor triggering the systematic decoupling, while surface latent heat flux, precipitation, and diurnal circulation did not play major roles. MBL clouds broke up over a short spatial region due to the changes in the synoptic conditions, implying that in real atmospheric conditions the MBL clouds do not have enough time to evolve as in the idealized models. (auth)

Zhou, Xiaoli [McGill Univ., Montreal, Quebec (Canada); Dept. of Atmospheric and Oceanic Sciences; Kollias, Pavlos [McGill Univ., Montreal, Quebec (Canada); Dept. of Atmospheric and Oceanic Sciences; Lewis, Ernie R. [Brookhaven National Lab., Upton, NY (United States). Biological, Environmental, and Climate Sciences Dept.

2015-03-01T23:59:59.000Z

103

Boundary-Layer Meteorol (2009) 132:129149 DOI 10.1007/s10546-009-9380-8  

E-Print Network [OSTI]

-Tunnel Investigation of Wind-Turbine Wakes: Boundary-Layer Turbulence Effects Leonardo P. Chamorro · Fernando Porté to study turbulence in the wake of a model wind turbine placed in a boundary layer developed over rough effects · Turbulence · Wake structure · Wind-tunnel experiment · Wind turbine L. P. Chamorro · F. Porté

Porté-Agel, Fernando

2009-01-01T23:59:59.000Z

104

Computation of hypersonic shock boundary layer interaction on a double wedge using a differential Reynolds Stress Model  

E-Print Network [OSTI]

Computation of hypersonic shock boundary layer interaction on a double wedge using a differential The simulation of hypersonic flows presents some difficulties due to the interaction between boundary layers on the standard test case of a subsonic flat plate and on a hypersonic configuration. The results show a good

105

Accumulation mode aerosol, pockets of open cells, and particle nucleation in the remote subtropical Pacific marine boundary layer  

E-Print Network [OSTI]

Accumulation mode aerosol, pockets of open cells, and particle nucleation in the remote subtropical in the remote subtropical Pacific marine boundary layer, J. Geophys. Res., 111, D02206, doi:10.1029/2004JD005694 the boundary layer via its action on the budgets of heat and water substance. A plausible consequence may

Russell, Lynn

106

Evaluating the Performance of Planetary Boundary Layer and Cloud Microphysical Parameterization Schemes in Convection-Permitting Ensemble Forecasts using  

E-Print Network [OSTI]

uncertainty in how to include various processes (e.g., drop breakup and ice-phase categories 1 Evaluating the Performance of Planetary Boundary Layer and Cloud Microphysical Parameterization In this study, the ability of several cloud microphysical and planetary boundary layer parameterization schemes

Xue, Ming

107

A novel Whole Air Sample Profiler (WASP) for the quantification of volatile organic compounds in the boundary layer  

SciTech Connect (OSTI)

The emission and fate of reactive VOCs is of inherent interest to those studying chemical biosphere-atmosphere interactions. In-canopy VOC observations are obtainable using tower-based samplers, but the lack of suitable sampling systems for the full boundary 5 layer has limited the data characterizing the vertical structure of such gases above the canopy height and still in the boundary layer. This is the important region where many reactive VOCs are oxidized or otherwise removed. Here we describe an airborne sampling system designed to collect a vertical profile of air into a 3/800 OD tube 150m in length. The inlet ram air pressure is used to flow sampled air through the 10 tube, which results in a varying flow rate based on aircraft speed and altitude. Since aircraft velocity decreases during ascent, it is necessary to account for the variable flow rate into the tube. This is accomplished using a reference gas that is pulsed into the air stream so that the precise altitude of the collected air can be reconstructed post-collection. The pulsed injections are also used to determine any significant effect 15 from diffusion/mixing within the sampling tube, either during collection or subsequent extraction for gas analysis. This system has been successfully deployed, and we show some measured vertical profiles of isoprene and its oxidation products methacrolein and methyl vinyl ketone from a mixed canopy near Columbia, Missouri.

Mak, J. E.; Su, L.; Guenther, Alex B.; Karl, Thomas G.

2013-10-16T23:59:59.000Z

108

Blockage of natural convection boundary layer flow in a multizone enclosure  

SciTech Connect (OSTI)

This paper reports the results of an experimental study that examines the transition between flow regimes, as a function of aperture size, in a two-zone enclosure with heated and cooled end walls. A constant heat flux boundary condition was maintained on one vertical end wall, and an isothermal cold temperature sink was maintained on the opposite vertical end wall. All of the remaining surfaces were highly insulated. The transition between the boundary layer driven regime and the bulk density driven regime was established as a function of the geometry of the aperture in the partition that separated the hot and cold zones. The results demonstrate that transition from the boundary layer driven regime to the bulk density driven regime is caused by blockage of the boundary layer flow, when the area of the flow aperture is reduced below a critical value. A simple flow model has been developed which predicts that the critical aperture area for the onset of flow blockage is directly proportional to the number of active heat transfer surfaces and inversely proportional to the Rayleigh number which characterizes the level of heating and cooling provided to the active heat transfer surfaces.

Scott, D.; Anderson, R.; Figliola, R.S.

1986-02-01T23:59:59.000Z

109

Boundary Layer  

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

Sea spray generation is determined by a source function that depends on background wind speed. Non-local mixing of the HBL caused by LE leads to the formation of a well-mixed HBL...

110

E-Print Network 3.0 - atmosphere-surface exchange processes Sample...  

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

atmospheric surface layer during CBLAST, in 16th Symposium on Boundary Layers... on heat, gas, and momentum transport, infrared remote sensing, upper-ocean processes,...

111

Using Mesoscale Weather Model Output as Boundary Conditions for Atmospheric Large-Eddy Simulations and Wind-Plant Aerodynamic Simulations (Presentation)  

SciTech Connect (OSTI)

Wind plant aerodynamics are directly affected by the microscale weather, which is directly influenced by the mesoscale weather. Microscale weather refers to processes that occur within the atmospheric boundary layer with the largest scales being a few hundred meters to a few kilometers depending on the atmospheric stability of the boundary layer. Mesoscale weather refers to large weather patterns, such as weather fronts, with the largest scales being hundreds of kilometers wide. Sometimes microscale simulations that capture mesoscale-driven variations (changes in wind speed and direction over time or across the spatial extent of a wind plant) are important in wind plant analysis. In this paper, we present our preliminary work in coupling a mesoscale weather model with a microscale atmospheric large-eddy simulation model. The coupling is one-way beginning with the weather model and ending with a computational fluid dynamics solver using the weather model in coarse large-eddy simulation mode as an intermediary. We simulate one hour of daytime moderately convective microscale development driven by the mesoscale data, which are applied as initial and boundary conditions to the microscale domain, at a site in Iowa. We analyze the time and distance necessary for the smallest resolvable microscales to develop.

Churchfield, M. J.; Michalakes, J.; Vanderwende, B.; Lee, S.; Sprague, M. A.; Lundquist, J. K.; Moriarty, P. J.

2013-10-01T23:59:59.000Z

112

Aircraft Observations of the Marine Boundary Layer Adjustment near Point Arguello, California  

E-Print Network [OSTI]

.g., Parish 2000). Several authors (e.g., Dorman 1985; Samelson 1992; Burk et al. 1999; Haack et al. 2001) represent the fluid system near the coast in terms of a two-layer shallow water model with the coastal terrain serving as a lateral boundary. The Froude... of the layer. Discontinuities such as hy- draulic jumps can result as the flow transitions from supercritical (Fr. 1) to subcritical (Fr, 1). As the flow in the MBL impinges on coastal points, significant modulation of the MBL height and wind field occurs...

Parish, Thomas R.; Rahn, David A.; Leon, David

2014-04-01T23:59:59.000Z

113

Experimental investigation of sound generation by a protuberance in a laminar boundary layer  

SciTech Connect (OSTI)

Sound radiation from a two-dimensional protuberance glued on the wall in a laminar boundary layer was investigated experimentally at low Mach numbers. When the protuberance was as high as the boundary-layer thickness, a feedback-loop mechanism set in between protuberance-generated sound and Tollmien-Schlichting (T-S) waves generated by the leading-edge receptivity to the upstream-propagating sound. Although occurrence of a separation bubble immediately upstream of the protuberance played important roles in the evolution of instability waves into vortices interacting with the protuberance, the frequency of tonal vortex sound was determined by the selective amplification of T-S waves in the linear instability stage upstream of the separation bubble and was not affected by the instability of the separation bubble.

Kobayashi, M.; Asai, M.; Inasawa, A. [Department of Aerospace Engineering, Tokyo Metropolitan University, 6-6 Asahigaoka, Hino, Tokyo 191-0065 (Japan)

2014-08-15T23:59:59.000Z

114

The effects of sound on the boundary layer of an airfoil at high angles of attack  

E-Print Network [OSTI]

* Numbers in parentheses refer to the References. introducing sound waves into the airstream by means of a variable-frequency oscillator and a loudspeaker mounted near the leading edge of a flat plate. Eventually, another method of producing... these disturbances was settled upon, but several interesting results caused by the use of sound were noted. Laminar boundary layer oscillations could be induced, depending upon the proper combination of sound frequency, speaker position, and free stream velocity...

Hutchinson, Thomas Ira

1963-01-01T23:59:59.000Z

115

34th AIAA Fluid Dynamics Conference and Exhibit, June 28July 1, 2004/Portland, OR DNS of Hypersonic Turbulent Boundary Layers  

E-Print Network [OSTI]

of Hypersonic Turbulent Boundary Layers M. Pino Martin Department of Mechanical and Aerospace Engineering and hypersonic turbu- lent boundary layers. The systematic procedure for initializing the turbulent flow fields layers is important in advancing supersonic and hypersonic flight technology. In a high-speed boundary

MartĂ­n, Pino

116

Prediction of continental shelf sediment transport using a theoretical model of the wave-current boundary layer  

E-Print Network [OSTI]

This thesis presents an application of the Grant-Madsen-Glenn bottom boundary layer model (Grant and Madsen, 1979; Glenn and Grant, 1987) to predictions of sediment transport on the continental shelf. The analysis is a ...

Goud, Margaret R

1987-01-01T23:59:59.000Z

117

Conditionally-Sampled Turbulent and Nonturbulent Measurements of Entropy Generation Rate in the Transition Region of Boundary Layers  

SciTech Connect (OSTI)

Conditionally-sampled boundary layer data for an accelerating transitional boundary layer have been analyzed to calculate the entropy generation rate in the transition region. By weighing the nondimensional dissipation coefficient for the laminar-conditioned-data and turbulent-conditioned-data with the intermittency factor the average entropy generation rate in the transition region can be determined and hence be compared to the time averaged data and correlations for steady laminar and turbulent flows. It is demonstrated that this method provides, for the first time, an accurate and detailed picture of the entropy generation rate during transition. The data used in this paper have been taken from detailed boundary layer measurements available in the literature. This paper provides, using an intermittency weighted approach, a methodology for predicting entropy generation in a transitional boundary layer.

D. M. McEligot; J. R. Wolf; K. P. Nolan; E. J. Walsh; R. J. Volino

2006-05-01T23:59:59.000Z

118

Variability of ozone in the marine boundary layer of the equatorial Pacific Ocean1 Xiao-Ming Hu1  

E-Print Network [OSTI]

marine boundary layer of the Kwajalein Atoll, Republic of the Marshall Islands (latitude 8o 43'3 N al., 2000; Horowitz et al., 2003; Yang et13 al., 2005; von Glasow, 2008). Due to logistical

Thompson, Anne

119

Numerical modeling of boundary layer flow under shoaling and breaking waves  

E-Print Network [OSTI]

is governed by the mass conservation equation 0U 0W ? + =0 0x 0" (2. 1) and the boundary layer approximation to the horizontal momentum equation DU 0U?0U 0 I 0U +U ?+ ? iv ? ?&utc& (2. 2) where D 0 0 0 ? = ? + U ? + W ?. Dt 0t 0z 0 (2. 3) In 2. 1 and 2... stresses. Following Kanetkar (1985), the governing equations 2. 11 and 2. 12 can be written to the first order of approximation as (3. 1) = cqql ? + ? cscsql ? ? ? ci? (3. 2) where the value of ci is found to be 0. 054 by setting production equal...

Pattipawaej, Olga Catherina

1998-01-01T23:59:59.000Z

120

X-ray and EUV Spectroscopy of the Boundary Layer Emission of Nonmagnetic Cataclysmic Variables  

E-Print Network [OSTI]

EUVE, ROSAT, and ASCA observations of the boundary layer emission of nonmagnetic cataclysmic variables (CVs) are reviewed. EUVE spectra reveal that the effective temperature of the soft component of high-Mdot nonmagnetic CVs is kT ~ 10-20 eV and that its luminosity is ~ 0.1-0.5 times the accretion disk luminosity. Although the EUV spectra are very complex and belie simple interpretation, the physical conditions of the boundary layer gas are constrained by emission lines of highly ionized Ne, Mg, Si, and Fe. ROSAT and ASCA spectra of the hard component of nonmagnetic CVs are satisfactorily but only phenomenologically described by multi-temperature thermal plasmas, and the constraints imposed on the physical conditions of this gas are limited by the relatively weak and blended lines. It is argued that significant progress in our understanding of the X-ray spectra of nonmagnetic CVs will come with future observations with XMM, AXAF, and Astro-E.

Christopher W. Mauche

1997-09-11T23:59:59.000Z

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


121

Pressure fluctuations beneath turbulent spots and instability wave packets in a hypersonic boundary layer.  

SciTech Connect (OSTI)

The development of turbulent spots in a hypersonic boundary layer was studied on the nozzle wall of the Boeing/AFOSR Mach-6 Quiet Tunnel. Under quiet flow conditions, the nozzle wall boundary layer remains laminar and grows very thick over the long nozzle length. This allows the development of large turbulent spots that can be readily measured with pressure transducers. Measurements of naturally occurring wave packets and developing turbulent spots were made. The peak frequencies of these natural wave packets were in agreement with second-mode computations. For a controlled study, the breakdown of disturbances created by spark and glow perturbations were studied at similar freestream conditions. The spark perturbations were the most effective at creating large wave packets that broke down into turbulent spots. The flow disturbances created by the controlled perturbations were analyzed to obtain amplitude criteria for nonlinearity and breakdown as well as the convection velocities of the turbulent spots. Disturbances first grew into linear instability waves and then quickly became nonlinear. Throughout the nonlinear growth of the wave packets, large harmonics are visible in the power spectra. As breakdown begins, the peak amplitudes of the instability waves and harmonics decrease into the rising broad-band frequencies. Instability waves are still visible on either side of the growing turbulent spots during this breakdown process.

Beresh, Steven Jay; Casper, Katya M.; Schneider, Steven P. (Purdue University, West Lafayette, IN)

2010-12-01T23:59:59.000Z

122

Transitions of cloud-topped marine boundary layers characterized by AIRS, MODIS, and a large eddy simulation model  

SciTech Connect (OSTI)

Cloud top entrainment instability (CTEI) is a hypothesized positive feedback between entrainment mixing and evaporative cooling near the cloud top. Previous theoretical and numerical modeling studies have shown that the persistence or breakup of marine boundary layer (MBL) clouds may be sensitive to the CTEI parameter. Collocated thermodynamic profile and cloud observations obtained from the Atmospheric Infrared Sounder (AIRS) and Moderate Resolution Imaging Spectroradiometer (MODIS) instruments are used to quantify the relationship between the CTEI parameter and the cloud-topped MBL transition from stratocumulus to trade cumulus in the northeastern Pacific Ocean. Results derived from AIRS and MODIS are compared with numerical results from the UCLA large eddy simulation (LES) model for both well-mixed and decoupled MBLs. The satellite and model results both demonstrate a clear correlation between the CTEI parameter and MBL cloud fraction. Despite fundamental differences between LES steady state results and the instantaneous snapshot type of observations from satellites, significant correlations for both the instantaneous pixel-scale observations and the long-term averaged spatial patterns between the CTEI parameter and MBL cloud fraction are found from the satellite observations and are consistent with LES results. This suggests the potential of using AIRS and MODIS to quantify global and temporal characteristics of the cloud-topped MBL transition.

Yue, Qing; Kahn, Brian; Xiao, Heng; Schreier, Mathias; Fetzer, E. J.; Teixeira, J.; Suselj, Kay

2013-08-16T23:59:59.000Z

123

Horizontal-Velocity and Variance Measurements in the Stable Boundary Layer Using Doppler Lidar: Sensitivity to Averaging Procedures  

SciTech Connect (OSTI)

Quantitative data on turbulence variables aloft--above the region of the atmosphere conveniently measured from towers--has been an important but difficult measurement need for advancing understanding and modeling of the stable boundary layer (SBL). Vertical profiles of streamwise velocity variances obtained from NOAA’s High Resolution Doppler Lidar (HRDL), which have been shown to be numerically equivalent to turbulence kinetic energy (TKE) for stable conditions, are a measure of the turbulence in the SBL. In the present study, the mean horizontal wind component U and variance ?u2 were computed from HRDL measurements of the line-of-sight (LOS) velocity using a technique described in Banta, et al. (2002). The technique was tested on datasets obtained during the Lamar Low-Level Jet Project (LLLJP) carried out in early September 2003, near the town of Lamar in southeastern Colorado. This paper compares U with mean wind speed obtained from sodar and sonic anemometer measurements. It then describes several series of averaging tests that produced the best correlation between TKE calculated from sonic anemometer data at several tower levels and lidar measurements of horizontal velocity variance ?u2. The results show high correlation (0.71-0.97) of the mean U and average wind speed measured by sodar and in-situ instruments, independent of sampling strategies and averaging procedures. Comparison of estimates of variance, on the other hand, proved sensitive to both the spatial and temporal averaging techniques.

Pichugina, Yelena L.; Banta, Robert M.; Kelley, Neil D.; Jonkman, Bonnie J.; Tucker, Sara C.; Newsom, Rob K.; Brewer, W. A.

2008-08-01T23:59:59.000Z

124

Pulsed Plasma with Synchronous Boundary Voltage for Rapid Atomic Layer Etching  

SciTech Connect (OSTI)

Atomic Layer ETching (ALET) of a solid with monolayer precision is a critical requirement for advancing nanoscience and nanotechnology. Current plasma etching techniques do not have the level of control or damage-free nature that is needed for patterning delicate sub-20 nm structures. In addition, conventional ALET, based on pulsed gases with long reactant adsorption and purging steps, is very slow. In this work, novel pulsed plasma methods with synchronous substrate and/or “boundary electrode” bias were developed for highly selective, rapid ALET. Pulsed plasma and tailored bias voltage waveforms provided controlled ion energy and narrow energy spread, which are critical for highly selective and damage-free etching. The broad goal of the project was to investigate the plasma science and engineering that will lead to rapid ALET with monolayer precision. A combined experimental-simulation study was employed to achieve this goal.

Economou, Demetre J.; Donnelly, Vincent M.

2014-05-13T23:59:59.000Z

125

Electron distributions observed with Langmuir waves in the plasma sheet boundary layer  

SciTech Connect (OSTI)

The present paper investigates the Langmuir turbulence driven by counter-streaming electron beams and its plausible association with observed features in the Earth's plasma sheet boundary layer region. A one-dimensional electrostatic particle-in-cell simulation code is employed in order to simulate broadband electrostatic waves with characteristic frequency in the vicinity of the electron plasma frequency ?/?{sub pe}?1.0. The present simulation confirms that the broadband electrostatic waves may indeed be generated by the counter-streaming electron beams. It is also found that the observed feature associated with low energy electrons, namely quasi-symmetric velocity space plateaus, are replicated according to the present simulation. However, the present investigation only partially succeeds in generating the suprathermal tails such that the origin of observed quasi power-law energetic population formation remains outstanding.

Hwang, Junga [Solar and Space Weather Research Group, Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of); Department of Astronomy and Space Science, University of Science and Technology, Daejeon (Korea, Republic of); Rha, Kicheol [Department of Physics, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Seough, Jungjoon [Solar and Space Weather Research Group, Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of); Yoon, Peter H. [School of Space Research, Kyung Hee University, Yongin-Si, Gyeonggi-Do 446-701 (Korea, Republic of); Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742 (United States)

2014-09-15T23:59:59.000Z

126

Photophoretic contribution to the transport of absorbing particles across combustion gas boundary layers  

SciTech Connect (OSTI)

Since radiation energy fluxes can be comparable to convective (Fourier) fluxes in large fossil-fuel-fired power stations and furnaces, the authors have examined particle drift (phoresis) induced by nonuniform photon-particle heating in a host gas. The authors analysis of the photophoretic velocity includes the important slipflow regime, and the numerical results show that photophoresis is a significant transport mechanism for micron-sized absorbing particles in high radiative transfer combustion environments, with equivalent photophoretic diffusivities (dimensionless photophoretic velocities) being as large as 10% of the better-known thermophoretic diffusivity (Rosner, 1980, 1985). Since previous experimental results (Rosner and Kim, 1984) demonstrated that thermophoresis causes over a 3-decade increase in particle deposition rates by convective diffusion, clearly, for small, absorbing particles, photophoresis will also be an important contributor to observed deposition rates. Accordingly, they present mass transfer coefficients for particle transport across laminar gaseous boundary layers, including both particle thermophoresis and photophoresis.

Castillo, J.L. (U.N.E.D., Madrid (Spain)); Mackowski, D.W.; Rosner, D.E. (Yale Univ., New Haven, CT (USA))

1989-01-01T23:59:59.000Z

127

'Maximum' entropy production in self-organized plasma boundary layer: A thermodynamic discussion about turbulent heat transport  

SciTech Connect (OSTI)

A thermodynamic model of a plasma boundary layer, characterized by enhanced temperature contrasts and ''maximum entropy production,'' is proposed. The system shows bifurcation if the heat flux entering through the inner boundary exceeds a critical value. The state with a larger temperature contrast (larger entropy production) sustains a self-organized flow. An inverse cascade of energy is proposed as the underlying physical mechanism for the realization of such a heat engine.

Yoshida, Z. [Graduate School of Frontier Sciences, University of Tokyo, Chiba 277-8561 (Japan); Mahajan, S. M. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)

2008-03-15T23:59:59.000Z

128

Boundary-Layer Meteorol (2010) 134:157180 DOI 10.1007/s10546-009-9433-z  

E-Print Network [OSTI]

of potential temperature w (Kms-1) Ks Soil thermal diffusivity (nominal value is 2.5 � 10-7 m2 s-1) k VonBoundary-Layer Meteorol (2010) 134:157­180 DOI 10.1007/s10546-009-9433-z ARTICLE Spectral Behaviour

Gentine, Pierre

129

IMPACT OF BOUNDARY-LAYER CUTTING AND FLOW CONDITIONING ON FREE-SURFACE BEHAVIOR IN TURBULENT LIQUID SHEETS  

E-Print Network [OSTI]

IMPACT OF BOUNDARY-LAYER CUTTING AND FLOW CONDITIONING ON FREE-SURFACE BEHAVIOR IN TURBULENT LIQUID dimension) = 1 cm into ambient air are compared with empirical correlations at a nearly prototypical term, for a well- conditioned jet but is not a substitute for well-designed flow conditioning. I

California at San Diego, University of

130

Boundary-Layer Meteorol (2008) 127:7395 DOI 10.1007/s10546-007-9255-9  

E-Print Network [OSTI]

-scale (SFS) models to reproduce the statistical proper- ties of SFS stresses and energy transfers over boundary layer. In this study, several SFS models are evaluated a priori using experimental data acquired down- wind of a rough-to-smooth transition in a wind tunnel. The SFS models studied include the eddy

Porté-Agel, Fernando

131

On the Interaction between Marine Boundary Layer Cellular Cloudiness and Surface Heat Fluxes  

SciTech Connect (OSTI)

The interaction between marine boundary layer cellular cloudiness and surface uxes of sensible and latent heat is investigated. The investigation focuses on the non-precipitating closed-cell state and the precipitating open-cell state at low geostrophic wind speed. The Advanced Research WRF model is used to conduct cloud-system-resolving simulations with interactive surface fluxes of sensible heat, latent heat, and of sea salt aerosol, and with a detailed representation of the interaction between aerosol particles and clouds. The mechanisms responsible for the temporal evolution and spatial distribution of the surface heat fluxes in the closed- and open-cell state are investigated and explained. It is found that the horizontal spatial structure of the closed-cell state determines, by entrainment of dry free tropospheric air, the spatial distribution of surface air temperature and water vapor, and, to a lesser degree, of the surface sensible and latent heat flux. The synchronized dynamics of the the open-cell state drives oscillations in surface air temperature, water vapor, and in the surface fluxes of sensible and latent heat, and of sea salt aerosol. Open-cell cloud formation, cloud optical depth and liquid water path, and cloud and rain water path are identified as good predictors of the spatial distribution of surface air temperature and sensible heat flux, but not of surface water vapor and latent heat flux. It is shown that by enhancing the surface sensible heat flux, the open-cell state creates conditions by which it is maintained. While the open-cell state under consideration is not depleted in aerosol, and is insensitive to variations in sea-salt fluxes, it also enhances the sea-salt flux relative to the closed-cell state. In aerosol-depleted conditions, this enhancement may replenish the aerosol needed for cloud formation, and hence contribute to the perpetuation of the open-cell state as well. Spatial homogenization of the surface fluxes is found to have only a small effect on cloud properties in the investigated cases. This indicates that sub-grid scale spatial variability in the surface flux of sensible and latent heat and of sea salt aerosol may not be required in large scale and global models to describe marine boundary layer cellular cloudiness.

Kazil, J.; Feingold, G.; Wang, Hailong; Yamaguchi, T.

2014-01-02T23:59:59.000Z

132

Open-loop control of noise amplification in a separated boundary layer flow  

SciTech Connect (OSTI)

Linear optimal gains are computed for the subcritical two-dimensional separated boundary-layer flow past a bump. Very large optimal gain values are found, making it possible for small-amplitude noise to be strongly amplified and to destabilize the flow. The optimal forcing is located close to the summit of the bump, while the optimal response is the largest in the shear layer. The largest amplification occurs at frequencies corresponding to eigenvalues which first become unstable at higher Reynolds number. Nonlinear direct numerical simulations show that a low level of noise is indeed sufficient to trigger random flow unsteadiness, characterized here by large-scale vortex shedding. Next, a variational technique is used to compute efficiently the sensitivity of optimal gains to steady control (through source of momentum in the flow, or blowing/suction at the wall). A systematic analysis at several frequencies identifies the bump summit as the most sensitive region for control with wall actuation. Based on these results, a simple open-loop control strategy is designed, with steady wall suction at the bump summit. Linear calculations on controlled base flows confirm that optimal gains can be drastically reduced at all frequencies. Nonlinear direct numerical simulations also show that this control allows the flow to withstand a higher level of stochastic noise without becoming nonlinearly unstable, thereby postponing bypass transition. In the supercritical regime, sensitivity analysis of eigenvalues supports the choice of this control design. Full restabilization of the flow is obtained, as evidenced by direct numerical simulations and linear stability analysis.

Boujo, E., E-mail: edouard.boujo@epfl.ch; Gallaire, F., E-mail: francois.gallaire@epfl.ch [Laboratory of Fluid Mechanics and Instabilities, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Ehrenstein, U., E-mail: ehrenstein@irphe.univ-mrs.fr [Aix Marseille Université, CNRS, Centrale Marseille, IRPHE UMR 7342, F-13384 Marseille (France)

2013-12-15T23:59:59.000Z

133

A method for the direct numerical simulation of hypersonic boundary-layer instability with finite-rate chemistry  

SciTech Connect (OSTI)

A new numerical method is presented here that allows to consider chemically reacting gases during the direct numerical simulation of a hypersonic fluid flow. The method comprises the direct coupling of a solver for the fluid mechanical model and a library providing the physio-chemical model. The numerical method for the fluid mechanical model integrates the compressible Navier–Stokes equations using an explicit time advancement scheme and high-order finite differences. This Navier–Stokes code can be applied to the investigation of laminar-turbulent transition and boundary-layer instability. The numerical method for the physio-chemical model provides thermodynamic and transport properties for different gases as well as chemical production rates, while here we exclusively consider a five species air mixture. The new method is verified for a number of test cases at Mach 10, including the one-dimensional high-temperature flow downstream of a normal shock, a hypersonic chemical reacting boundary layer in local thermodynamic equilibrium and a hypersonic reacting boundary layer with finite-rate chemistry. We are able to confirm that the diffusion flux plays an important role for a high-temperature boundary layer in local thermodynamic equilibrium. Moreover, we demonstrate that the flow for a case previously considered as a benchmark for the investigation of non-equilibrium chemistry can be regarded as frozen. Finally, the new method is applied to investigate the effect of finite-rate chemistry on boundary layer instability by considering the downstream evolution of a small-amplitude wave and comparing results with those obtained for a frozen gas as well as a gas in local thermodynamic equilibrium.

Marxen, Olaf, E-mail: olaf.marxen@vki.ac.be [Center for Turbulence Research, Building 500, Stanford University, Stanford, CA 94305-3035 (United States) [Center for Turbulence Research, Building 500, Stanford University, Stanford, CA 94305-3035 (United States); Aeronautics and Aerospace Department, von Karman Institute for Fluid Dynamics, Chaussée de Waterloo, 72, 1640 Rhode-St-Genèse (Belgium); Magin, Thierry E. [Aeronautics and Aerospace Department, von Karman Institute for Fluid Dynamics, Chaussée de Waterloo, 72, 1640 Rhode-St-Genèse (Belgium)] [Aeronautics and Aerospace Department, von Karman Institute for Fluid Dynamics, Chaussée de Waterloo, 72, 1640 Rhode-St-Genèse (Belgium); Shaqfeh, Eric S.G.; Iaccarino, Gianluca [Center for Turbulence Research, Building 500, Stanford University, Stanford, CA 94305-3035 (United States)] [Center for Turbulence Research, Building 500, Stanford University, Stanford, CA 94305-3035 (United States)

2013-12-15T23:59:59.000Z

134

A one-dimensional sectional model to simulate multicomponent aerosol dynamics in the marine boundary layer 1. Model description  

SciTech Connect (OSTI)

A one-dimensional, multicomponent sectional model has been developed to simulate the temporal and vertical variations of the aerosol size distribution and composition in the marine boundary layer (MBL). An important aspect of the model is its ability to handle the transport of aerosols in an atmosphere with humidity gradients with no numerical diffusion caused by the swelling and shrinking of the particles as they move through the humidity gradients. This is achieved by rewriting the aerosol general dynamical equation (GDE) in terms of dry radius thus transferring all variations in radius caused by temporal and spatial humidity variations to the rate coefficients appearing in the equations. The model then solves the new GDE in fixed dry size sections, with the humidity dependence of the processes now included in variable coefficients. This procedure also results in correct gradient transport. A limiting assumption is that the particles equilibrate instantaneously with the ambient water vapor. This assumption limits the maximum particle size which can be treated in the model to ambient (wet) radii less than about 30 {mu}m. All processes currently believed to be important in shaping the MBL size distribution are included in the current version of the model. These include generation of sea-salt aerosol at the ocean surface, nucleation of new particles, coagulation, growth due to condensation of gas-phase reaction products, growth due to sulfate formation during cloud processing, precipitation scavenging, surface deposition, turbulent mixing, gravitational settling, and exchange with the free troposphere. Simple gas-phase chemistry which includes the oxidation of dimethylsulfide and SO{sub 2} to sulfate is incorporated in the current version of the model. {copyright} 1998 American Geophysical Union

Fitzgerald, J.W.; Hoppel, W.A. [Remote Sensing Division, Naval Research Laboratory, Washington, District of Columbia (United States)] [Remote Sensing Division, Naval Research Laboratory, Washington, District of Columbia (United States); Gelbard, F. [Modeling and Analysis Department, Sandia National Laboratories, Albuquerque, New Mexico (United States)] [Modeling and Analysis Department, Sandia National Laboratories, Albuquerque, New Mexico (United States)

1998-07-01T23:59:59.000Z

135

ANGULAR MOMENTUM TRANSPORT BY ACOUSTIC MODES GENERATED IN THE BOUNDARY LAYER. II. MAGNETOHYDRODYNAMIC SIMULATIONS  

SciTech Connect (OSTI)

We perform global unstratified three-dimensional magnetohydrodynamic simulations of an astrophysical boundary layer (BL)-an interface region between an accretion disk and a weakly magnetized accreting object such as a white dwarf-with the goal of understanding the effects of magnetic field on the BL. We use cylindrical coordinates with an isothermal equation of state and investigate a number of initial field geometries including toroidal, vertical, and vertical with zero net flux. Our initial setup consists of a Keplerian disk attached to a non-rotating star. In a previous work, we found that in hydrodynamical simulations, sound waves excited by shear in the BL were able to efficiently transport angular momentum and drive mass accretion onto the star. Here we confirm that in MHD simulations, waves serve as an efficient means of angular momentum transport in the vicinity of the BL, despite the magnetorotational instability (MRI) operating in the disk. In particular, the angular momentum current due to waves is at times larger than the angular momentum current due to MRI. Our results suggest that angular momentum transport in the BL and its vicinity is a global phenomenon occurring through dissipation of waves and shocks. This point of view is quite different from the standard picture of transport by a local anomalous turbulent viscosity. In addition to angular momentum transport, we also study magnetic field amplification within the BL. We find that the field is indeed amplified in the BL, but only by a factor of a few, and remains subthermal.

Belyaev, Mikhail A.; Rafikov, Roman R.; Stone, James M., E-mail: rrr@astro.princeton.edu [Department of Astrophysical Sciences, Princeton University, Ivy Lane, Princeton, NJ 08540 (United States)

2013-06-10T23:59:59.000Z

136

Atmospheric Sciences Program Department of Marine, Earth and Atmospheric Sciences (MEAS)  

E-Print Network [OSTI]

atmospheric chemistry/air quality, boundary layer and air pollution meteorology, regional/global climatology MODELING OF MULTIPLE AIR POLLUTANTS AT URBAN AND REGIONAL SCALES Our atmosphere is a complex systemAtmospheric Sciences Program Department of Marine, Earth and Atmospheric Sciences (MEAS) (http

Parker, Matthew D. Brown

137

Atmospheric pressure spatial atomic layer deposition web coating with in situ monitoring of film thickness  

SciTech Connect (OSTI)

Spectral reflectometry was implemented as a method for in situ thickness monitoring in a spatial atomic layer deposition (ALD) system. Al{sub 2}O{sub 3} films were grown on a moving polymer web substrate at 100?°C using an atmospheric pressure ALD web coating system, with film growth of 0.11–0.13?nm/cycle. The modular coating head design and the in situ monitoring allowed for the characterization and optimization of the trimethylaluminum and water precursor exposures, purge flows, and web speed. A thickness uniformity of ±2% was achieved across the web. ALD cycle times as low as 76?ms were demonstrated with a web speed of 1?m/s and a vertical gap height of 0.5?mm. This atmospheric pressure ALD system with in situ process control demonstrates the feasibility of low-cost, high throughput roll-to-roll ALD.

Yersak, Alexander S.; Lee, Yung C. [Department of Mechanical Engineering, University of Colorado at Boulder, 1045 Regent Drive, 422 UCB, Boulder, Colorado 80309-0422 (United States); Spencer, Joseph A.; Groner, Markus D., E-mail: mgroner@aldnanosolutions.com [ALD NanoSolutions, Inc., 580 Burbank Street, Unit 100, Broomfield, Colorado 80020 (United States)

2014-01-15T23:59:59.000Z

138

Application of Atmospheric Plasma-Sprayed Ferrite Layers for Particle Accelerators  

E-Print Network [OSTI]

A common problem in all kinds of cavity-like structures in particle accelerators is the occurrence of RF-resonances. Typically, ferrite plates attached to the walls of such structures as diagnostic devices, kickers or collimators, are used to dampen those undesired modes. However, the heat transfer rate from these plates to the walls is rather limited. Brazing ferrite plates to the walls is not possible in most cases due to the different thermal expansion coefficients. To overcome those limitations, atmospheric plasma spraying techniques have been investigated. Ferrite layers with a thickness from 50 ?m to about 300 ?m can be deposited on metallic surfaces like stainless steel exhibiting good thermal contact and still reasonable absorption properties. In this paper the technological aspects of plasma deposition are discussed and results of specifically developed RF loss measurement procedures for such thin magnetically lossy layers on metal are presented.

Caspers, F; Federmann, S; Taborelli, M; Schulz, C; Bobzin, K; Wu, J

2013-01-01T23:59:59.000Z

139

On the relationship between temperature and wind speed in the atmospheric surface layer  

E-Print Network [OSTI]

LIBRAR& A AN m os??E " "" ON THE RELATIONSHIP BETWEEN T" MP. "RATURE AND WIND SPEED IN THE ATMOSPHERIC SURFACE LAYER A Thesis John Me Pierrard Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial... logarithmically with height+ Also, the choice of a method of determination of the roughness length must be governed by an awareness of possible errors in the wind speed meas- urementso The system used to collect the data employed in this study is susceptible...

Pierrard, John Martin

2012-06-07T23:59:59.000Z

140

Nitric oxide emissions from the high-temperature viscous boundary layers of hypersonic aircraft within the stratosphere  

SciTech Connect (OSTI)

The authors study the nitric oxide emission characteristics of supersonic aircraft resulting from heating of viscous boundary layers along the skin of the aircraft. Previous study has concentrated on nitric oxide emissions coming from combustion products from the scramjet engines. This work shows that above mach 8, emissions from viscous heating become a significant factor in total emission of nitric oxide. Above mach 16 it becomes the dominant source of emission.

Brooks, S.B.; Lewis, M.J.; Dickerson, R.R. [Univ. of Maryland, College Park, MD (United States)

1993-09-20T23:59:59.000Z

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


141

Nitrogen Oxides in the Nocturnal Boundary Layer: Chemistry of Nitrous Acid (HONO) and the Nitrate Radical (N03)  

SciTech Connect (OSTI)

Summary Chemical processes occurring at night in the lowest part of the urban atmosphere, the so called nocturnal boundary layer (NBL), can influence the composition of the atmosphere during the night as well as the following day. They may impact the budgets of some of the most important pollutants, such as ozone and nitrogen oxides, as well as influence size and composition of particular matter. Few studies have thus far concentrated on the nocturnal chemistry of the urban NBL, most likely due to the strong influence of vertical transport and mixing, which requires the measurement of trace gas profiles instead of simple point observations. Motivated by our lack of observations and understanding of nocturnal chemistry, the focus of this project was the study of the vertical distribution of trace gases and the altitude dependence of nocturnal chemistry under polluted conditions through field observations and modeling studies. The analysis of three field experiments (TEXAQS, Houston, 2000; Phoenix Sunrise Ozone Experiment, 2001; NAPOX, Boston, 2002), two of which were performed in this project, showed that ozone concentrations typically increase with height in the lowest 150m, while NO2 typically decreases. NO3, the dominant nocturnal radical species, showed much higher concentrations in the upper part of the NBL, and was often not present at the ground. With the help of a one-dimensional chemical transport model, developed in this project, we found that the interaction of ground emissions of NOx and hydrocarbons, together with their vertical transport, is responsible for the vertical profiles. The dominant chemical reactions influencing ozone, NO2 and NO3 are the reaction of ozone and NO3 with freshly emitted NO. Sensitivity studies with our model showed that the magnitude of the trace gas gradients depend both on the emission rates and the vertical stability of the NBL. Observations and model analysis clearly show that nocturnal chemistry in urban areas is altitude dependent. Measurements at one altitude, for example at the ground, where most air quality monitoring stations are located, are not representative for the rest of the NBL. Our model also revealed that radical chemistry is, in general, altitude dependent at night. We distinguish three regions: an unreactive, NO rich, ground layer; an upper, O3 and NO3 dominated layer, and a reactive mixing layer, where RO2 radicals are mixed from aloft with NO from the ground. In this reactive layer an active radical chemistry and elevated OH radical levels can be found. The downward transport of N2O5 and HO2NO2, followed by their thermal decay, was also identified as a radical source in this layer. Our observations also gave insight into the formation of HONO in the NBL. Based on our field experiments we were able to show that the NO2 to HONO conversion was relative humidity dependent. While this fact was well known, we found that it is most likely the uptake of HONO onto surfaces which is R.H. dependent, rather than the NO2 to HONO conversion. This finding led to the proposal of a new NO2 to HONO conversion mechanism, which is based on solid physical chemical principles. Noteworthy is also the observation of enhanced NO2 to HONO conversion during a dust storm event in Phoenix. The final activity in our project investigated the influence of the urban canopy, i.e. building walls and surfaces, on nocturnal chemistry. For the first time the surface area of a city was determined based on a Geographical Information System database of the city of Santa Monica. The surface to volume areas found in this study showed that, in the 2 lower part of the NBL, buildings provide a much larger surface area than the aerosol. In addition, buildings take up a considerable amount of the volume near the ground. The expansion of our model and sensitivity studies based on the Santa Monica data revealed that the surface area of buildings considerably influences HONO levels in urban areas. The volume reduction leads to a decrease of O3 and an increase of NO2 near the ground due to the stronger impact o

Jochen Stutz

2005-05-24T23:59:59.000Z

142

Immersed Boundary Methods for High-Resolution Simulation of Atmospheric Boundary-Layer Flow Over Complex Terrain  

E-Print Network [OSTI]

in today’s numerical weather prediction models is stillability of a numerical weather prediction model to predictthe context of numerical weather prediction models. The two-

Lundquist, Katherine Ann

2010-01-01T23:59:59.000Z

143

Immersed Boundary Methods for High-Resolution Simulation of Atmospheric Boundary-Layer Flow Over Complex Terrain  

E-Print Network [OSTI]

Wind Energy Association Windpower 2008 Conference, AmericanWind Energy Association Windpower 2006 Conference, American

Lundquist, Katherine Ann

2010-01-01T23:59:59.000Z

144

Collaborative Research: ARM observations for the development and evaluation of models and parameterizations of cloudy boundary layers  

SciTech Connect (OSTI)

This is a collaborative project with Dr. Ping Zhu at Florida International University. It was designed to address key issues regarding the treatment of boundary layer cloud processes in climate models with UM’s research focusing on the analyses of ARM cloud radar observations from MMCR and WACR and FIU’s research focusing on numerical simulations of boundary layer clouds. This project capitalized on recent advancements in the ARM Millimeter Cloud Radar (MMCR) processing and the development of the WACR (at the SGP) to provide high temporal and spatial resolution Doppler cloud radar measurements for characterizing in-cloud turbulence, large-eddy circulations, and high resolution cloud structures of direct relevance to high resolution numerical modeling studies. The principal focus of the observational component of this collaborative study during this funding period was on stratocumulus clouds over the SGP site and fair-weather cumuli over the Nauru site. The statistical descriptions of the vertical velocity structures in continental stratocumulus clouds and in the Nauru shallow cumuli that are part of this study represents the most comprehensive observations of the vertical velocities in boundary layer clouds to date and were done in collaboration with Drs. Virendra Ghate and Pavlos Kollias.

Albrecht, Bruce,

2013-07-12T23:59:59.000Z

145

MEMS Pressure Sensor Array for Aeroacoustic Analysis of the Turbulent Boundary Layer  

E-Print Network [OSTI]

holes Density of air c Speed of sound ” Viscosity of air 1 Density of diaphragm (Polysilicon) E1 Modulus of elasticity of diaphragm 1 Poisson's ratio of diaphragm t2 Thickness of Parylene-C layer 2 Density of Parylene-C layer E2 Modulus of elasticity of Parylene-C layer Research Assistant, Department

White, Robert D.

146

Large-eddy Simulation of the Nighttime Stable Atmospheric Boundary Layer  

E-Print Network [OSTI]

eddy Simulation of Wind-turbine Wakes: Evaluation of Turbineperformed LES of wind-turbine wakes in neutrally stratified

Zhou, Bowen

2012-01-01T23:59:59.000Z

147

Atmospheric Boundary Layer Studies with Unified RANS-LES and Dynamic LES Methods  

E-Print Network [OSTI]

of existing wind farms is their relatively low efficiency. Due to the wind turbine wakes, the efficiency of wind farms is reduced by 20 to 50 percent compared to turbines in isolation. Therefore, there is a significant need for research related to the interaction of wind turbines with the surrounding air flow

Heinz, Stefan

148

Large-eddy Simulation of the Nighttime Stable Atmospheric Boundary Layer  

E-Print Network [OSTI]

by providing accurate vertical wind speed profiles. TurbineC-1 Schematic of vertical wind speed and density profiles in50,000 s) vertical profiles of wind speed for the moderately

Zhou, Bowen

2012-01-01T23:59:59.000Z

149

An investigation of the air flow structure over a rooftop in the turbulent atmospheric boundary layer  

E-Print Network [OSTI]

wind speed, the mean vertical wind speed, and the verticalA variation in the mean vertical wind speed was observed forpredominantly positive vertical wind speed, whereas the

Hayes, William Joseph

2010-01-01T23:59:59.000Z

150

DOE/SC-ARM-14-034 Lower Atmospheric Boundary Layer Experiment  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct: CrudeOffice ofINL is a U.S. Department of42 The350 ARM1234

151

Large-eddy Simulation of the Nighttime Stable Atmospheric Boundary Layer  

E-Print Network [OSTI]

coordinate and (b) wind and potential temperature at the up-coordinate and (b) wind and potential temperature at the up-Mean profiles of wind and potential temperature, turbulent

Zhou, Bowen

2012-01-01T23:59:59.000Z

152

Friction of a slider on a granular layer: Non-monotonic thickness dependence and effect of boundary conditions  

E-Print Network [OSTI]

We investigate the effective friction encountered by a mass sliding on a granular layer as a function of bed thickness and boundary roughness conditions. The observed friction has minima for a small number of layers before it increases and saturates to a value which depends on the roughness of the sliding surface. We use an index-matched interstitial liquid to probe the internal motion of the grains with fluorescence imaging in a regime where the liquid has no significant effect on the measured friction. The shear profiles obtained as a function of depth show decrease in slip near the sliding surface as the layer thickness is increased. We propose that the friction depends on the degree of grain confinement relative to the sliding surfaces.

Saloome Siavoshi; Ashish V. Orpe; Arshad Kudrolli

2005-12-22T23:59:59.000Z

153

Horizontal Velocity and Variance Measurements in the Stable Boundary Layer Using Doppler Lidar: Sensitivity to Averaging Procedures  

SciTech Connect (OSTI)

Quantitative data on turbulence variables aloft--above the region of the atmosphere conveniently measured from towers--have been an important but difficult measurement need for advancing understanding and modeling of the stable boundary layer (SBL). Vertical profiles of streamwise velocity variances obtained from NOAA's high-resolution Doppler lidar (HRDL), which have been shown to be approximately equal to turbulence kinetic energy (TKE) for stable conditions, are a measure of the turbulence in the SBL. In the present study, the mean horizontal wind component U and variance {sigma}2u were computed from HRDL measurements of the line-of-sight (LOS) velocity using a method described by Banta et al., which uses an elevation (vertical slice) scanning technique. The method was tested on datasets obtained during the Lamar Low-Level Jet Project (LLLJP) carried out in early September 2003, near the town of Lamar in southeastern Colorado. This paper compares U with mean wind speed obtained from sodar and sonic anemometer measurements. The results for the mean U and mean wind speed measured by sodar and in situ instruments for all nights of LLLJP show high correlation (0.71-0.97), independent of sampling strategies and averaging procedures, and correlation coefficients consistently >0.9 for four high-wind nights, when the low-level jet speeds exceeded 15 m s{sup -1} at some time during the night. Comparison of estimates of variance, on the other hand, proved sensitive to both the spatial and temporal averaging parameters. Several series of averaging tests are described, to find the best correlation between TKE calculated from sonic anemometer data at several tower levels and lidar measurements of horizontal-velocity variance {sigma}{sup 2}{sub u}. Because of the nonstationarity of the SBL data, the best results were obtained when the velocity data were first averaged over intervals of 1 min, and then further averaged over 3-15 consecutive 1-min intervals, with best results for the 10- and 15-min averaging periods. For these cases, correlation coefficients exceeded 0.9. As a part of the analysis, Eulerian integral time scales ({tau}) were estimated for the four high-wind nights. Time series of {tau} through each night indicated erratic behavior consistent with the nonstationarity. Histograms of {tau} showed a mode at 4-5 s, but frequent occurrences of larger {tau} values, mostly between 10 and 100 s.

Pichugina, Y. L.; Banta, R. M.; Kelley, N. D.; Jonkman, B. J.; Tucker, S. C.; Newsom, R. K.; Brewer, W. A.

2008-08-01T23:59:59.000Z

154

The Effects of Step Excrescences on Swept-Wing Boundary-Layer Transition  

E-Print Network [OSTI]

flutter and handling-quality clearance flight proved the new test article is safe for the flight-testing experiments. Pressure measurements are compared with computational results, infrared thermography is used to globally detect boundary...

Duncan, Jr., Glen T.

2014-08-12T23:59:59.000Z

155

Seismic and gravitational studies of melting in the mantle's thermal boundary layers  

E-Print Network [OSTI]

This thesis presents three studies which apply geophysical tools to the task of better understanding mantle melting phenomena at the upper and lower boundaries of the mantle. The first study uses seafloor bathymetry and ...

Van Ark, Emily M

2007-01-01T23:59:59.000Z

156

The effect of tangential mass addition on the boundary layer velocity distribution of a flat plate at zero angle of attack  

E-Print Network [OSTI]

. V . RESULTS AND DISCUSSION 16 18 20 21 24 Boundary Layer Conditions Downstream of Blowing Slot . Boundary Layer Conditions Upstream of Slot Accuracy of Data 24 40 47 VI. CONCLUSIONS AND RECOMMENDATIONS ~ 51 LITERATURE CITED 54 APPENDIX... 55 Estimation of Error Caused by Leaks in the Pressure Measuring System 56 LIST OF FIGURES Figure Page 3" x 48" Smoke Tunnel 2. Flat Plate Model 3. Schematic of Pressure System 4. Volume Flow Rates of Working Pipe Tap Orifice 14 Variation...

Miller, Edward Peter

2012-06-07T23:59:59.000Z

157

MEMS Pressure Sensor Array for Aeroacoustic Analysis of the Turbulent Boundary Layer  

E-Print Network [OSTI]

vent holes Cc Center­to­center spacing of vent holes Density of air c Speed of sound ” Viscosity of air 1 Density of diaphragm (Polysilicon) E1 Modulus of elasticity of diaphragm 1 Poisson's ratio Density of Parylene-C layer E2 Modulus of elasticity of Parylene-C layer 2 Poisson's ratio of Parylene

White, Robert D.

158

Harmonic propagation of variability in surface energy balance within a coupled soil-vegetation-atmosphere system  

E-Print Network [OSTI]

[1] The response of a soil-vegetation-atmosphere continuum model to incoming radiation forcing is investigated in order to gain insights into the coupling of soil and atmospheric boundary layer (ABL) states and fluxes. The ...

Gentine, P.

159

Velocity and temperature distribution of air in the boundary layer of a vertical plate for free-convective heat transfer  

E-Print Network [OSTI]

against the nozzle and clamped to. a stand in such a way that its vertical position could be, set. as desired. Hot-Wire Anemometer A Plow Corporation Model HWB2 hot wire anemometer was used in connection with a single, filament, probe to measure...VELOCITY AND TEMPERATURE DISTRIBUTION OF AIR IN THE BOUNDARY LAYER OF A VERTICAL PLATE FOR FREE-CONVECTIVE HEAT TRANSFER A Thesis By JEAN MAXIME JOSE JULLIENNE Submitted to . the . Graduate School of the Agricultural. and Mechanical. College...

Jullienne, Jean Maxime Jose

2012-06-07T23:59:59.000Z

160

Alternate Designs of Ultrasonic Absorptive Coatings for Hypersonic Boundary Layer Control  

E-Print Network [OSTI]

-wall boundary condition. A particular case with a relatively shallow cavities and very high porosity showed number, wawb/”w Re Reynolds number, eUe/”e s Cavity spacing T Temperature t Time U Freestream streamwise of thermal protection systems (TPS).2,3 State-of- the-art active and reactive lam- inar flow control (LFC

Dabiri, John O.

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


161

Microstructure of Josephson junctions: Effect on supercurrent transport in YBCO grain boundary and barrier layer junctions  

SciTech Connect (OSTI)

The electric transport of high-temperature superconductors, such as YBa{sub 2}Cu{sub 3}O{sub 7{minus}x} (YBCO), can be strongly restricted by the presence of high-angle grain boundaries (GB). This weak-link behavior is governed by the macroscopic GB geometry and the microscopic grain boundary structure and composition at the atomic level. Whereas grain boundaries present a considerable impediment to high current applications of high T{sub c} materials, there is considerable commercial interest in exploiting the weak-link-nature of grain boundaries for the design of microelectronic devices, such as superconducting quantum interference devices (SQUIDs). The Josephson junctions which form the basis of this technology can also be formed by introducing artificial barriers into the superconductor. The authors have examined both types of Josephson junctions by EM techniques in an effort to understand the connection between microstructure/chemistry and electrical transport properties. This knowledge is a valuable resource for the design and production of improved devices.

Merkle, K.L.; Huang, Y.

1998-01-01T23:59:59.000Z

162

Characterization of Radar Boundary Layer Data Collected During the 2001 Multi-Frequency Radar IOP  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation SitesStandingtheir Atmospheric Impacts. | EMSL Organic Coatings

163

Use of shear-stress-sensitive, temperature-insensitive liquid crystals for hypersonic boundary-layer transition detection  

SciTech Connect (OSTI)

The use of shear-stress-sensitive, temperature-insensitive (SSS/TI) liquid crystals (LCs) has been evaluated as a boundary-layer transition detection technique for hypersonic flows. Experiments were conducted at Mach 8 in the Sandia National Laboratories Hypersonic Wind Tunnel using a flat plate model at near zero-degree angle of attack over the freestream unit Reynolds number range 1.2-5.8x10{sup 6}/ft. Standard 35mm color photography and Super VHS color video were used to record LC color changes due to varying surface shear stress during the transition process for a range of commercial SSS liquid crystals. Visual transition data were compared to an established method using calorimetric surface heat-transfer measurements to evaluate the LC technique. It is concluded that the use of SSS/TI LCs can be an inexpensive, safe, and easy to use boundary-layer transition detection method for hypersonic flows. However, a valid interpretation of the visual records requires careful attention to illumination intensity levels and uniformity, lighting and viewing angles, some prior understanding of the general character of the flow, and the selection of the appropriate liquid crystal for the particular flow conditions.

Aeschliman, D.P.; Croll, R.H.; Kuntz, D.W.

1997-04-01T23:59:59.000Z

164

American Institute of Aeronautics and Astronautics The Influence of Stable Boundary Layer Flows  

E-Print Network [OSTI]

the Great Plains' wind resources favorable for wind energy production. At the same time, the presence, University of Texas, Austin, TX 78712, USA Sukanta Basu2 Dept. of Geosciences, Texas Tech University, Lubbock, University of Texas, Austin, TX 78712, USA Near-neutral atmospheric stability conditions form the basis

Manuel, Lance

165

Hygroscopic growth of submicron and supermicron aerosols in the marine boundary layer  

E-Print Network [OSTI]

balance and climate directly through absorption and scattering of the incoming solar radiation and indirectly through modification of cloud properties [Intergovernmental Panel on Climate Change, 2007 behaviors of the dynamic and complex atmospheric aerosol consisting of particles with a wide range of sizes

166

Squeezout phenomena and boundary layer formation of a model ionic liquid under confinement and charging  

E-Print Network [OSTI]

Electrical charging of parallel plates confining a model ionic liquid down to nanoscale distances yields a variety of charge-induced changes in the structural features of the confined film. That includes even-odd switching of the structural layering and charging-induced solidification and melting, with important changes of local ordering between and within layers, and of squeezout behavior. By means of molecular dynamics simulations, we explore this variety of phenomena in the simplest charged Lennard-Jones coarse-grained model including or excluding the effect a neutral tail giving an anisotropic shape to one of the model ions. Using these models and open conditions permitting the flow of ions in and out of the interplate gap, we simulate the liquid squeezout to obtain the distance dependent structure and forces between the plates during their adiabatic appraoch under load. Simulations at fixed applied force illustrate an effective electrical pumping of the ionic liquid, from a thick nearly solid film that withstands the interplate pressure for high plate charge to complete squeezout following melting near zero charge. Effective enthalpy curves obtained by integration of interplate forces versus distance show the local minima that correspond to layering, and predict the switching between one minimum and another under squeezing and charging.

R. Capozza; A. Vanossi; A. Benassi; E. Tosatti

2014-12-22T23:59:59.000Z

167

Posters Triggering of Boundary Layer Cumulus Clouds Over a Heterogeneous Surface  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006PhotovoltaicSeptember 22, 2014SocietyJ. Dudhia515 Posters Triggering

168

Four-Dimensional Data Assimilation Boundary-Layer Observations Over the Southern  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsing ZirconiaPolicyFeasibilityFieldMinds" Give Forms (AllKurt's ColumnThe

169

Regional Scale Surface CO2 Exchange Estimates Using a Boundary Layer Budget  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared at 278, 298,NIST3 AÇORIANONews Media » 2014 RegionalMethod over

170

Local Correlations and Multi-Fractal Behaviour in Marine Boundary Layer Cloud Dynamics  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6,Local Correlations and Multi-Fractal Behaviour in

171

Sensitivity of Boundary-layer and Deep Convective Cloud Simulations to  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systemsBi (2) SrEvaluating theDepartment ofscreen-printedVertical

172

Simulation of Post-Frontal Boundary Layers Observed During the ARM 2000 Cloud IOP  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systemsBi (2)Sharing Smart GridShiftMethod forAThiols on

173

Stress concentration near stiff inclusions: validation of rigid inclusion model and boundary layers by means of photoelasticity  

E-Print Network [OSTI]

Photoelasticity is employed to investigate the stress state near stiff rectangular and rhombohedral inclusions embedded in a 'soft' elastic plate. Results show that the singular stress field predicted by the linear elastic solution for the rigid inclusion model can be generated in reality, with great accuracy, within a material. In particular, experiments: (i.) agree with the fact that the singularity is lower for obtuse than for acute inclusion angles; (ii.) show that the singularity is stronger in Mode II than in Mode I (differently from a notch); (iii.) validate the model of rigid quadrilateral inclusion; (iv.) for thin inclusions, show the presence of boundary layers deeply influencing the stress field, so that the limit case of rigid line inclusion is obtained in strong dependence on the inclusion's shape. The introduced experimental methodology opens the possibility of enhancing the design of thin reinforcements and of analyzing complex situations involving interaction between inclusions and defects.

Diego Misseroni; Francesco Dal Corso; Summer Shahzad; Davide Bigoni

2014-04-03T23:59:59.000Z

174

Behavior of buoyant moist plumes in turbulent atmospheres  

E-Print Network [OSTI]

A widely applicable computational model of buoyant moist plumes in turbulent atmospheres has been constructed. To achieve this a one dimensional Planetary Boundary Layer (P.B.L.) model has been developed to account for ...

Hamza, Redouane

1981-01-01T23:59:59.000Z

175

E-Print Network 3.0 - atmospheric surface layer Sample Search...  

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

determining albedo and opacity Clouds Snow and ice Aerosols Time... Horizontal transport in the atmosphere Dry and moist static energy Eddy ... Source: Sherwood, Steven -...

176

High-resolution moisture fields retrieved for the first time from both operational and research radars illustrate the low-level moisture variability associated with boundary layer  

E-Print Network [OSTI]

radars illustrate the low-level moisture variability associated with boundary layer processes-Resolution, Low-Level Moisture Fields from Operational NexRad and Research Radars by Rita D. RobeRts, FRĂ©DĂ©Ric Fab vapor measurements extracted from radar using an index of refraction (refractivity) technique developed

Reising, Steven C.

177

Clouds, Aerosol, and Precipitation in the Marine Boundary Layer: Analysis of Results from the ARM Mobile Facility Deployment to the Azores (2009/2010)  

SciTech Connect (OSTI)

The project focuses upon dataset analysis and synthesis of datasets from the AMF deployment entitled “Clouds, Aerosols, and Precipitation in the Marine Boundary Layer (CAP?MBL)” at Graciosa Island in the Azores. Wood is serving a PI for this AMF deployment.

Wood, Robert [University of Washington, Dept of Atmos Sci

2013-05-31T23:59:59.000Z

178

Boundary layer (shear-band) in frustrated viscoplastic flows T. CHEVALIER, S. RODTS, X. CHATEAU, J. BOUJLEL, M. MAILLARD, P. COUSSOT  

E-Print Network [OSTI]

(paints, mortars, concrete, drilling fluids) in food industry and cooking (purees, sauces, dough stress fluids give rise to a boundary layer, which takes the form of a liquid region of uniform stress fluids such as concentrated colloids, emul- sions, foams, are jammed systems which behave as liq

Boyer, Edmond

179

Self-Sustaining Process through Streak Generation in a Flat-Plate Boundary Layer Thomas Duriez, Jean-Luc Aider, and Jose Eduardo Wesfreid  

E-Print Network [OSTI]

Self-Sustaining Process through Streak Generation in a Flat-Plate Boundary Layer Thomas Duriez July 2009; published 28 September 2009) The existence of a self-sustaining process between streamwise-bounded turbulence. The existence of a self- sustaining process (SSP) between these two flow structures has been

Wesfreid, José Eduardo

180

Impact of the Vertical Mixing Induced by Low-level Jets on Boundary Layer Ozone4 Concentration5  

E-Print Network [OSTI]

to the ground, while the upper24 region of the daytime mixed layer becomes the residual layer (RL). Mixing40 chemical reactions and dry deposition, which resulted in lower O3 peak values on the next day.41 layer (SBL) near45 the surface that is typically quite shallow. Above the SBL is a residual layer (RL

Xue, Ming

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


181

Intercomparison of cloud model simulations of Arctic mixed-phase boundary layer clouds observed during SHEBA/FIRE-ACE  

SciTech Connect (OSTI)

An intercomparison of six cloud-resolving and large-eddy simulation models is presented. This case study is based on observations of a persistent mixed-phase boundary layer cloud gathered on 7 May, 1998 from the Surface Heat Budget of Arctic Ocean (SHEBA) and First ISCCP Regional Experiment - Arctic Cloud Experiment (FIRE-ACE). Ice nucleation is constrained in the simulations in a way that holds the ice crystal concentration approximately fixed, with two sets of sensitivity runs in addition to the baseline simulations utilizing different specified ice nucleus (IN) concentrations. All of the baseline and sensitivity simulations group into two distinct quasi-steady states associated with either persistent mixed-phase clouds or all-ice clouds after the first few hours of integration, implying the existence of multiple equilibria. These two states are associated with distinctly different microphysical, thermodynamic, and radiative characteristics. Most but not all of the models produce a persistent mixed-phase cloud qualitatively similar to observations using the baseline IN/crystal concentration, while small increases in the IN/crystal concentration generally lead to rapid glaciation and conversion to the all-ice state. Budget analysis indicates that larger ice deposition rates associated with increased IN/crystal concentrations have a limited direct impact on dissipation of liquid in these simulations. However, the impact of increased ice deposition is greatly enhanced by several interaction pathways that lead to an increased surface precipitation flux, weaker cloud top radiative cooling and cloud dynamics, and reduced vertical mixing, promoting rapid glaciation of the mixed-phase cloud for deposition rates in the cloud layer greater than about 1-2x10-5 g kg-1 s-1. These results indicate the critical importance of precipitation-radiative-dynamical interactions in simulating cloud phase, which have been neglected in previous fixed-dynamical parcel studies of the cloud phase parameter space. Large sensitivity to the IN/crystal concentration also suggests the need for improved understanding of ice nucleation and its parameterization in models.

Morrison, H.; Zuidema, Paquita; Ackerman, Andrew; Avramov, Alexander; de Boer, Gijs; Fan, Jiwen; Fridlind, Ann; Hashino, Tempei; Harrington, Jerry Y.; Luo, Yali; Ovchinnikov, Mikhail; Shipway, Ben

2011-06-16T23:59:59.000Z

182

Coupled Vadose Zone and Atmospheric Surface-Layer Transport of CO2 from Geologic Carbon Sequestration Sites  

SciTech Connect (OSTI)

Geologic carbon dioxide (CO{sub 2}) sequestration is being considered as a way to offset fossil-fuel-related CO{sub 2} emissions to reduce the rate of increase of atmospheric CO{sub 2} concentrations. The accumulation of vast quantities of injected carbon dioxide (CO{sub 2}) in geologic sequestration sites may entail health and environmental risks from potential leakage and seepage of CO{sub 2} into the near-surface environment. We are developing and applying a coupled subsurface and atmospheric surface-layer modeling capability built within the framework of the integral finite difference reservoir simulator TOUGH2. The overall purpose of modeling studies is to predict CO{sub 2} concentration distributions under a variety of seepage scenarios and geologic, hydrologic, and atmospheric conditions. These concentration distributions will provide the basis for determining above-ground and near-surface instrumentation needs for carbon sequestration monitoring and verification, as well as for assessing health, safety, and environmental risks. A key feature of CO{sub 2} is its large density ({rho} = 1.8 kg m{sup -3}) relative to air ({rho} = 1.2 kg m{sup -3}), a property that may allow small leaks to cause concentrations in air above the occupational exposure limit of 4 percent in low-lying and enclosed areas such as valleys and basements where dilution rates are low. The approach we take to coupled modeling involves development of T2CA, a TOUGH2 module for modeling the multicomponent transport of water, brine, CO{sub 2}, gas tracer, and air in the subsurface. For the atmospheric surface-layer advection and dispersion, we use a logarithmic vertical velocity profile to specify constant time-averaged ambient winds, and atmospheric dispersion approaches to model mixing due to eddies and turbulence. Initial simulations with the coupled model suggest that atmospheric dispersion quickly dilutes diffuse CO{sub 2} seepage fluxes to negligible concentrations, and that rainfall infiltration causes CO{sub 2} to return to the subsurface as a dissolved component in infiltrating rainwater.

Oldenburg, Curtis M.; Unger, Andre J.A.

2004-03-29T23:59:59.000Z

183

Soil moisture regulates the biological response of elevated atmospheric CO2 concentrations in a coupled  

E-Print Network [OSTI]

and Atmospheric Sciences, Purdue University, United States b Departments of Geography and Atmospheric and Oceanic Sciences, University of California at Los Angeles, United States Received 16 March 2005; received surface model, dynamically coupled to an atmospheric boundary layer and surface energy balance scheme

Niyogi, Dev

184

High-Resolution Large-Eddy Simulations of Scalar Transport in Atmospheric Boundary Layer Flow over Complex Terrain  

E-Print Network [OSTI]

of Electric Power Industry, Chiba, Japan FOTINI KATOPODES CHOW Department of Civil and Environmental to the choice of numerical simulation parameters than is typically needed for mean wind field predictions. Large-eddy simulation is used in a mesoscale setting, providing modeling advantages through the use of robust turbulence

Chow, Fotini Katopodes

185

A Large-Eddy Simulation Study of the Influence of Subsidence on the Stably Stratified Atmospheric Boundary Layer  

E-Print Network [OSTI]

snow/ice pack interior, which constrains surface cooling.snow/ice pack. They suggest that the strong cooling of theice pack. During clear-sky conditions, strong radiative cooling

Mirocha, Jeffrey D.; Kosovi?, Branko

2010-01-01T23:59:59.000Z

186

A Large-Eddy Simulation Study of the Influence of Subsidence on the Stably Stratified Atmospheric Boundary Layer  

E-Print Network [OSTI]

temperature, wind speed, vertical heat and momentum ?uxes,ABL is vertical wind shear, with the wind speed at the

Mirocha, Jeffrey D.; Kosovi?, Branko

2010-01-01T23:59:59.000Z

187

Isolating Effects of Water Table Dynamics, Terrain, and Soil Moisture Heterogeneity on the Atmospheric Boundary Layer Using Coupled Models  

E-Print Network [OSTI]

depth (PBLD), (b) vertical wind speed (w), (c) latent heatdepth (PBLD), (b) vertical wind speed (w), (c) latent heatdepth (PBLD) and (b) vertical wind speed (w) versus water

Rihani, Jehan

2010-01-01T23:59:59.000Z

188

A Large-Eddy Simulation Study of the Influence of Subsidence on the Stably Stratified Atmospheric Boundary Layer  

E-Print Network [OSTI]

Mean pro?les of potential temperature, wind speed, verticalsection. 4.1 Potential Temperature and Wind Speed Pro?lesequilibrium LES potential temperature and wind speed pro?les

Mirocha, Jeffrey D.; Kosovi?, Branko

2010-01-01T23:59:59.000Z

189

A Comparison of Atmospheric Reanalysis Surface Products over the Ocean and Implications for Uncertainties in Air–Sea Boundary Forcing  

E-Print Network [OSTI]

This paper investigates the uncertainties related to atmospheric fields from reanalysis products used in forcing ocean models. Four reanalysis products, namely from 1) the interim ECMWF Re-Analysis (ERA-Interim), 2) version ...

Chaudhuri, Ayan H.

190

Soil moisture in complex terrain: quantifying effects on atmospheric boundary layer flow and providing improved surface boundary conditions for mesoscale models  

E-Print Network [OSTI]

74 ii Soil Moisture Sensors: Decagon ECH2O Capacitance133 A.10 Soil types corresponding to each75 Soil Moisture and Temperature Probe

Daniels, Megan Hanako

2010-01-01T23:59:59.000Z

191

Soil moisture in complex terrain: quantifying effects on atmospheric boundary layer flow and providing improved surface boundary conditions for mesoscale models  

E-Print Network [OSTI]

red indicates “water towers” generated by kinematic wavethe kinematic wave equation will begin to collect water onred indicates “water towers” generated by kinematic wave

Daniels, Megan Hanako

2010-01-01T23:59:59.000Z

192

Soil moisture in complex terrain: quantifying effects on atmospheric boundary layer flow and providing improved surface boundary conditions for mesoscale models  

E-Print Network [OSTI]

compressible numerical weather prediction model incompressible numerical weather prediction model withcompressible numerical weather prediction model in

Daniels, Megan Hanako

2010-01-01T23:59:59.000Z

193

Soil moisture in complex terrain: quantifying effects on atmospheric boundary layer flow and providing improved surface boundary conditions for mesoscale models  

E-Print Network [OSTI]

direction, (b) wind speed, (c) potential temperature, and (Airport of potential temperature, wind speed, winderrors (bias) for potential temperature, wind speed, wind

Daniels, Megan Hanako

2010-01-01T23:59:59.000Z

194

Adding Complex Terrain and Stable Atmospheric Condition Capability to the Simulator for On/Offshore Wind Farm Applications (SOWFA) (Presentation)  

SciTech Connect (OSTI)

This presentation describes changes made to NREL's OpenFOAM-based wind plant aerodynamics solver so that it can compute the stably stratified atmospheric boundary layer and flow over terrain. Background about the flow solver, the Simulator for Off/Onshore Wind Farm Applications (SOWFA) is given, followed by details of the stable stratification/complex terrain modifications to SOWFA, along with some preliminary results calculations of a stable atmospheric boundary layer and flow over a simple set of hills.

Churchfield, M. J.

2013-06-01T23:59:59.000Z

195

On Techniques to Characterize and Correlate Grain Size, Grain Boundary Orientation and the Strength of the SiC Layer of TRISO Coated Particles: A Preliminary Study  

SciTech Connect (OSTI)

The mechanical properties of the silicon carbide (SiC) layer of the TRi-ISOtropic (TRISO) coated particle (CP) for high temperature gas reactors (HTGR) are performance parameters that have not yet been standardized by the international HTR community. Presented in this paper are the results of characterizing coated particles to reveal the effect of annealing temperature (1000 to 2100°C) on the strength and grain size of unirradiated coated particles. This work was further expanded to include possible relationships between the grain size and strength values. The comparative results of two strength measurement techniques and grain size measured by the Lineal intercept method are included. Preliminary grain boundary characterization results determined by electron backscatter diffraction (EBSD) are included. These results are also important for future fission product transport studies, as grain boundary diffusion is identified as a possible mechanism by which 110mAg, one of the fission activation products, might be released through intact SiC layers. Temperature is a parameter known to influence the grain size of SiC and therefore it is important to investigate the effect of high temperature annealing on the SiC grain size. Recommendations and future work will also be briefly discussed.

I.J.van Rooyen; J.L. Dunzik Gougar; T. Trowbridge; Philip M van Rooyen

2012-10-01T23:59:59.000Z

196

DOI 10.1007/s10546-006-9050-z Boundary-Layer Meteorology (2006) 120: 315351 Springer 2006  

E-Print Network [OSTI]

parametrization for the urban surface energy balance. A three-day period was modelled and evaluated against data THERMODYNAMIC ISLAND IN A COASTAL CITY ANALYSED FROM AN OPTIMIZED SURFACE NETWORK GR ŽEGOIRE PIGEON,1, AUDE on the study of the urban atmosphere over the coastal city of Marseille. A methodology developed to optimize

Ribes, Aurélien

2006-01-01T23:59:59.000Z

197

Vertical Velocity and Buoyancy Characteristics of Coherent Echo Plumes in the Convective Boundary Layer, Detected by a Profiling Airborne Radar  

E-Print Network [OSTI]

scatterers (mostly insects). In this study, airborne radar measurements of the CBL are combined with flight-level Layer, Detected by a Profiling Airborne Radar QUN MIAO AND BART GEERTS University of Wyoming, Laramie 20 June 2005, in final form 8 November 2005) ABSTRACT Aircraft and airborne millimeter-wave radar

Geerts, Bart

198

Water Structure at Aqueous Solution Surfaces of Atmospherically Relevant Dimethyl Sulfoxide and Methanesulfonic Acid Revealed by Phase-Sensitive Sum Frequency  

E-Print Network [OSTI]

layer (MBL), the sulfur cycle dominates in the gas-to-particle conversion process and in the growth-containing aerosols play an important role in atmospheric chemistry and climate.1-3 Especially in the marine boundary

199

Interface boundary conditions for dynamic magnetization and spin wave dynamics in a ferromagnetic layer with the interface Dzyaloshinskii-Moriya interaction  

SciTech Connect (OSTI)

In this work, we derive the interface exchange boundary conditions for the classical linear dynamics of magnetization in ferromagnetic layers with the interface Dzyaloshinskii-Moriya interaction (IDMI). We show that IDMI leads to pinning of dynamic magnetization at the interface. An unusual peculiarity of the IDMI-based pinning is that its scales as the spin-wave wave number. We incorporate these boundary conditions into an existing numerical model for the dynamics of the Damon-Eshbach spin wave in ferromagnetic films. IDMI affects the dispersion and the frequency non-reciprocity of the travelling Damon-Eshbach spin wave. For a broad range of film thicknesses L and wave numbers, the results of the numerical simulations of the spin wave dispersion are in a good agreement with a simple analytical expression, which shows that the contribution of IDMI to the dispersion scales as 1/L, similarly to the effect of other types of interfacial anisotropy. Suggestions to experimentalists how to detect the presence of IDMI in a spin wave experiment are given.

Kostylev, M. [School of Physics, M013, University of Western Australia, Crawley, Perth 6009, Western Australia (Australia)

2014-06-21T23:59:59.000Z

200

Scientific uncertainties in atmospheric mercury models III: Boundary and initial conditions, model grid resolution, and Hg(II) reduction mechanism  

SciTech Connect (OSTI)

In this study, the model response in terms of simulated mercury concentration and deposition to boundary condition (BC), initial condition (IC), model grid resolution (12 km versus 36 km), and two alternative Hg(II) reduction mechanisms, was investigated. The model response to the change of gaseous elemental mercury (GEM) concentration from 0 to 2 ngm3 in IC/BC is found to be very linear (r240.99) based on the results of sensitivity simulations in July 2001. An increase of 1 ngm3 of GEM in BC resulted in an increase of 0.81 ngm3 in the monthly average of total mercury concentration, and 1270 ngm2 in the monthly total deposition. IC has similar but weaker effects compared to those of BC. An increase of 1 ngm3 of GEM in IC resulted in an increase of 0.14 ngm3 in the monthly average of total mercury concentration, and 250 ngm2 in the monthly total deposition. Varying reactive gaseous mercury (RGM) or particulate mercury (PHg) in BC/IC has much less significant impact. Simulation results at different grid resolutions show good agreement (slope 0.950 1.026, r 0.816 0.973) in mercury concentration, dry deposition, and total deposition. The agreement in wet deposition is somewhat weaker (slope 0.770 0.794, r 0.685 0.892) due to the difference in emission dilution and simulated precipitation that subsequently change reaction rates in the aqueous phase. Replacing the aqueous Hg(II)-HO2 reduction by either RGM reduction by CO (51018cm3 molecule1 s1) or photoreduction of RGM (1105 s1) gives significantly better model agreement with the wet deposition measured by Mercury Deposition Network (MDN). Possible ranges of the reduction rates are estimated based on model sensitivity results. The kinetic estimate requires further verification by laboratory studies.

Lin, Che-Jen [ORNL; Pongprueksa, Pruek [Lamar University; Lindberg, Steven Eric [ORNL; Jang, Carey [U.S. Environmental Protection Agency, Raleigh, North Carolina; Braverman, Thomas [U.S. Environmental Protection Agency, Raleigh, North Carolina; Bullock, Russell O [NOAA; Ho, Thomas [ORNL; Chu, Hsing-Wei [Lamar University

2008-03-01T23:59:59.000Z

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


201

Johnson et al.: Europa's Sputter-induced Atmosphere 507 Composition and Detection of Europa's  

E-Print Network [OSTI]

Johnson et al.: Europa's Sputter-induced Atmosphere 507 507 Composition and Detection of Europa's Sputter-induced Atmosphere R. E. Johnson University of Virginia M. H. Burger University of Maryland, it is also called a surface boundary-layer atmos- phere (Johnson, 2002), i.e., as at Mercury, the Moon

Johnson, Robert E.

202

www.solas-int.org //00//00 surface ocean -lower atmosphere study Mid-Term Strategy theme: Air-sea gas fluxes at Eastern boundary Upwelling and Oxygen Minimum Zone (OMZ) systems  

E-Print Network [OSTI]

www.solas-int.org //00//00 surface ocean - lower atmosphere study Mid-Term Strategy theme: Air at the SOLAS workshop on "Air-sea fluxes at the Eastern Boundary Upwelling and OMZ systems" 8-10 November 2010

203

ATMOSPHERIC TURBULENCE MODELING AND IMPLICATIONS FOR WIND ENERGY  

E-Print Network [OSTI]

turbines off too early in high winds, or may risk severe damage to the rotors and blades by operating under Introduction Wind turbines sit at the very bottom of the at- mospheric boundary layer, where winds are highly turbulent, shear events are intermittent, and land- atmosphere interactions may be strong. Turbine hub

Chow, Fotini Katopodes

204

Cloud climatology at the Southern Great Plains and the layer structure, drizzle, and atmospheric modes of continental stratus  

E-Print Network [OSTI]

with other data sets, climate-scale relation- ships between cloud properties and dynamical or micro- physical of cloud layers, an issue that is important in calculating both the radiative and the hydro- logic effects

205

Atmospheric and Wake Turbulence Impacts on Wind Turbine Fatigue Loading: Preprint  

SciTech Connect (OSTI)

Large-eddy simulations of atmospheric boundary layers under various stability and surface roughness conditions are performed to investigate the turbulence impact on wind turbines. In particular, the aeroelastic responses of the turbines are studied to characterize the fatigue loading of the turbulence present in the boundary layer and in the wake of the turbines. Two utility-scale 5 MW turbines that are separated by seven rotor diameters are placed in a 3 km by 3 km by 1 km domain. They are subjected to atmospheric turbulent boundary layer flow and data is collected on the structural response of the turbine components. The surface roughness was found to increase the fatigue loads while the atmospheric instability had a small influence. Furthermore, the downstream turbines yielded higher fatigue loads indicating that the turbulent wakes generated from the upstream turbines have significant impact.

Lee, S.; Churchfield, M.; Moriarty, P.; Jonkman, J.; Michalakes, J.

2011-12-01T23:59:59.000Z

206

Global warming and its implications for conservation. 3. How does it work? Part two: atmospheric science and the layer model  

E-Print Network [OSTI]

that energy comes in from the sun and shines back out to space as IR. The main points are: 1. The outflow of IR energy from a planet must balance heating from the sun. 2. The planet accomplishes this balance warms the surface of the planet as it moves toward an equilibrium of energy fluxes in and out. The layer

Creel, Scott

207

Boundary streaming with Navier boundary condition Jin-Han Xiea)  

E-Print Network [OSTI]

is the fluid's kinematic shear viscosity and is the wave's angular frequency. In water, and for frequencies applications involving high-frequency acoustic waves over a solid boundary, the Stokes boundary-layer thickness to travelling and standing waves shows that the boundary slip respectively increases and decreases the streaming

Vanneste, Jacques

208

8, 88178846, 2008 Observed boundary-  

E-Print Network [OSTI]

ACPD 8, 8817­8846, 2008 Observed boundary- layer/mesoscale impacts on Saharan dust J. H. Marsham et and Enviroment, University of Leeds, Leeds, UK 2 Institut fšur Meteorologie und Klimaforschung, Universit@env.leeds.ac.uk) 8817 #12;ACPD 8, 8817­8846, 2008 Observed boundary- layer/mesoscale impacts on Saharan dust J. H

Paris-Sud XI, Université de

209

Correlation Between Grain and Grain-Boundary Critical Current Densities in ex situ Coated Conductors with Variable YBa2Cu3O7- ? Layer Thickness  

SciTech Connect (OSTI)

The dependence of the percolative critical current density at low magnetic fields on YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) layer thickness is studied by comparing grain, J{sub c}{sup G}, and grain-boundary, J{sub c}{sup GB}, critical current densities for a series of ex situ processed YBCO films on a RABiTS template. Both critical current densities decrease as a function of thickness and the values of J{sub c}{sup G} and J{sub c}{sup GB} show a clear correlation which suggests the existence of an interaction between Abrikosov-Josephson vortices on the grain boundaries and Abrikosov vortices in the bulk of the grains. This opens the possibility to improve J{sub c}{sup GB} by optimizing the pinning capabilities of the grains.

Palau, A. [ICMAB, Barcelona, Spain; Puig, T. [ICMAB, Barcelona, Spain; Obradors, X. [ICMAB, Barcelona, Spain; Feenstra, Roeland [ORNL; Gapud, Albert Agcaoili [ORNL

2006-01-01T23:59:59.000Z

210

Investigating the local atmospheric response to a5 realistic shift in the Oyashio sea surface6  

E-Print Network [OSTI]

, where extratropical SST forcing produces31 shallow anomalous heating balanced by strong equatorward cold the atmosphere, beyond basic thermodynamic air-sea coupling via59 turbulent boundary layer heat flux exchange, most of the SST anomaly induced diabatic heating ( ) is balanced by29 poleward transient eddy heat

Newman, Matthew

211

Atmospheric Environment 36 (2002) 51855196 FTIR measurements of functional groups and organic mass in  

E-Print Network [OSTI]

the National Center for Atmospheric Research C-130 aircraft during the passing efficiency of a low, with higher Al/Ca ratios in the boundary layer. Organic compounds were present in high and low dust conditions or may condense onto pre- existing particles. Partly as a result of this vapor-to- particle conversion

Russell, Lynn

212

Atmospheric science and power production  

SciTech Connect (OSTI)

This is the third in a series of scientific publications sponsored by the US Atomic Energy Commission and the two later organizations, the US Energy Research and Development Adminstration, and the US Department of Energy. The first book, Meteorology and Atomic Energy, was published in 1955; the second, in 1968. The present volume is designed to update and to expand upon many of the important concepts presented previously. However, the present edition draws heavily on recent contributions made by atmospheric science to the analysis of air quality and on results originating from research conducted and completed in the 1970s. Special emphasis is placed on how atmospheric science can contribute to solving problems relating to the fate of combustion products released into the atmosphere. The framework of this book is built around the concept of air-quality modeling. Fundamentals are addressed first to equip the reader with basic background information and to focus on available meteorological instrumentation and to emphasize the importance of data management procedures. Atmospheric physics and field experiments are described in detail to provide an overview of atmospheric boundary layer processes, of how air flows around obstacles, and of the mechanism of plume rise. Atmospheric chemistry and removal processes are also detailed to provide fundamental knowledge on how gases and particulate matter can be transformed while in the atmosphere and how they can be removed from the atmosphere. The book closes with a review of how air-quality models are being applied to solve a wide variety of problems. Separate analytics have been prepared for each chapter.

Randerson, D. (ed.)

1984-07-01T23:59:59.000Z

213

Diamond and Related Materials, 2 (1993) 661 666 661 Degenerate four-wave mixing diagnostics of atmospheric pressure  

E-Print Network [OSTI]

-3]. An r.f. inductively coupled plasma offers the benefits of an "electrodeless" discharge for minimum film application of this new spectroscopic technique to an atmospheric pressure plasma synthesis reactor. DFWM measurements of the CH radicals in the boundary layer of an r.f. inductively coupled plasma deposition reactor

Zare, Richard N.

214

Measurement of Boundary-Layer Temperature Profiles by a Scanning 5-MM Radiometer During the 1999 Winter NSA/AAO Radiometer Exp  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMapping the Nanoscale LandscapeImportsBG4, 2012 1:00core1

215

Clouds, Aerosols and Precipitation in the Marine Boundary Layer (CAP-MBL) AMF Deployment Graciosa Island, Azores, NE Atlantic Ocean May 2009-December 2010  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New SubstationClean Communities of WesternVailCloisteredPresence3 Cloudiness Inter-

216

Pacific Northwest Laboratory annual report for 1984 to the DOE Office of Energy Research. Part 3. Atmospheric sciences  

SciTech Connect (OSTI)

The goals of atmospheric research at Pacific Northwest Laboratory (PNL) are to assess, describe, and predict the nature and fate of atmospheric contaminants and to study the impacts of contaminants on local, regional, and global climates. The contaminants being investigated are those resulting from the development and use of conventional resources (coal, gas, oil, and nuclear power) as well as alternative energy sources. The description of the research is organized into 3 sections: (1) Atmospheric Studies in Complex Terrain (ASCOT); (2) Boundary Layer Meteorology; and (3) Dispersion, Deposition, and Resuspension of Atmospheric Contaminants. Separate analytics have been done for each of the sections and are indexed and contained in the EDB. (MDF)

Elderkin, C.E.

1985-02-01T23:59:59.000Z

217

Grain boundary defects initiation at the outer surface of dissimilar welds: Corrosion mechanism studies  

SciTech Connect (OSTI)

Dissimilar welds located on the primary coolant system of the French PWR plants exhibit grain boundary defects in the true austenitic zones of the first buttering layer. If grain boundaries reach the interface, they can extend to the martensitic band. Those defects are filled with compact oxides. In addition, the ferritic base metal presents some pits along the interface. Nowadays, three mechanisms are proposed to explain the initiation of those defects: stress corrosion cracking, intergranular corrosion and high temperature intergranular oxidation. This paper is dealing with the study of the mechanisms involved in the corrosion phenomenon. Intergranular corrosion tests performed on different materials show that only the first buttering layer, even with some {delta} ferrite, is sensitized. The results of stress corrosion cracking tests in water solutions show that intergranular cracking is possible on a bulk material representative of the first buttering layer. It is unlikely on actual dissimilar welds where the ferritic base metal protects the first austenitic layer by galvanic coupling. Therefore, the stress corrosion cracking assumption cannot explain the initiation of the defects in aqueous environment. The results of the investigations and of the corrosion studies led to the conclusion that the atmosphere could be the only possible aggressive environment. This conclusion is based on natural atmospheric exposure and accelerated corrosion tests carried out with SO{sub 2} additions in controlled atmosphere. They both induce a severe intergranular corrosion on true sensitized austenitic materials.

Bouvier, O. De; Yrieix, B. [Electricite De France, Moret Sur Loing (France). Research and Development Division

1995-12-31T23:59:59.000Z

218

Atmospheric heat redistribution and collapse on tidally locked rocky planets  

E-Print Network [OSTI]

Atmospheric collapse is likely to be of fundamental importance to tidally locked rocky exoplanets but remains understudied. Here, general results on the heat transport and stability of tidally locked terrestrial-type atmospheres are reported. First, the problem is modeled with an idealized 3D general circulation model (GCM) with gray gas radiative transfer. It is shown that over a wide range of parameters the atmospheric boundary layer, rather than the large-scale circulation, is the key to understanding the planetary energy balance. Through a scaling analysis of the interhemispheric energy transfer, theoretical expressions for the day-night temperature difference and surface wind speed are created that reproduce the GCM results without tuning. Next, the GCM is used with correlated-k radiative transfer to study heat transport for two real gases (CO2 and CO). For CO2, empirical formulae for the collapse pressure as a function of planetary mass and stellar flux are produced, and critical pressures for atmospher...

Wordsworth, Robin

2014-01-01T23:59:59.000Z

219

Stability of Small Viscosity Noncharacteristic Boundary Layers  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . 17 1.3.2 The mixed Cauchy-problem . . . . . . . . . . . . . . . 17 1.4 BKW expansions

MĂ©tivier, Guy

220

Stability of Small Viscosity Noncharacteristic Boundary Layers  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . 17 1.3.2 The mixed Cauchy­problem . . . . . . . . . . . . . . . 17 1.4 BKW expansions

MĂ©tivier, Guy

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


221

Convective Instability of a Boundary Layer with  

E-Print Network [OSTI]

proportional to the integral over the depth of the lithosphere of the 19 #12;ratio of thermal buoyancy. Such instabilities are driven by the negative thermal buoyancy of the cold lithosphere and retarded largely for driving convective downwelling. For non-Newtonian viscosity with power law exponent n and temperature

Conrad, Clint

222

Thunderstorm influence on boundary layer winds  

E-Print Network [OSTI]

of this research was to develop a conceptual model of selected pre-storm ambient conditions as a function of the strength of a thunderstorm's outflow. The time of maximum rainfall during the thunderstorm in relation to the time of maximum outflow was a... selected for study from well-defined Code 3 cells (thunderstorms). The results indicated that two conceptual models were necessary to describe the pre-storm ambient conditions that led to thunderstorm development and outflow. One model contained...

Schmidt, Jill Marie

1986-01-01T23:59:59.000Z

223

ARM - Measurement - Planetary boundary layer height  

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

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224

Boundary Layer Lubrication | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

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225

Boundary Layer Lubrication Mechanisms | Department of Energy  

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

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226

Boundary Layer Lubrication Mechanisms | Department of Energy  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up fromDepartmentTie Ltd: ScopeDepartment1, 2011DepartmentBosch PowertrainBoulder1 DOE0

227

Boundary Layer Lubrication | Department of Energy  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up fromDepartmentTie Ltd: ScopeDepartment1, 2011DepartmentBosch PowertrainBoulder12009

228

ChEAS Data: The Chequamegon Ecosystem Atmosphere Study  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The Chequamegon Ecosystem-Atmosphere Study (ChEAS) is a multi-organizational research effort studying biosphere/atmosphere interactions within a northern mixed forest in Northern Wisconsin. A primary goal is to understand the processes controlling forest-atmosphere exchange of carbon dioxide and the response of these processes to climate change. Another primary goal is to bridge the gap between canopy-scale flux measurements and the global CO2 flask sampling network. The ChEAS flux towers participate in AmeriFlux, and the region is an EOS-validation site. The WLEF tower is a NOAA-CMDL CO2 sampling site. ChEAS sites are primarily located within or near the Chequamegon-Nicolet National Forest in northern Wisconsin, with one site in the Ottawa National Forest in the upper peninsula of Michigan. Current studies observe forest/atmosphere exchange of carbon dioxide at canopy and regional scales, forest floor respiration, photosynthesis and transpiration at the leaf level and use models to scale to canopy and regional levels. EOS-validation studies quantitatively assess the land cover of the area using remote sensing and conduct extensive ground truthing of new remote sensing data (i.e. ASTER and MODIS). Atmospheric remote sensing work is aimed at understanding atmospheric boundary layer dynamics, the role of entrainment in regulating the carbon dioxide mixing ratio profiles through the lower troposphere, and feedback between boundary layer dynamics and vegetation (especially via the hydrologic cycle). Airborne studies have included include balloon, kite and aircraft observations of the CO2 profile in the troposphere.

Davis, Kenneth J.(Penn State)

229

Journal of Atmospheric and Solar-Terrestrial Physics 69 (2007) 191211 The magnetosphereionosphere system from the perspective of  

E-Print Network [OSTI]

and plasmasheet boundary layer and in downward-current ``pressure cookers.'' Observational evidence indicating

230

Atmospheric dispersion in mountain valleys and basins  

SciTech Connect (OSTI)

The primary goal of the research is to further characterize and understand dispersion in valley and basin atmospheres. A secondary, and related goal, is to identify and understand the dominant physical processes governing this dispersion. This has been accomplished through a review of the current literature, and analyses of recently collected data from two field experiments. This work should contribute to an improved understanding of material transport in the atmospheric boundary layer. It was found that dispersion in a freely draining valley (Brush Creek valley, CO) atmosphere is much greater than in an enclosed basin (Roanoke, VA) atmosphere primarily because of the greater wind speeds moving past the release point and the greater turbulence levels. The development of a cold air pool in the Roanoke basin is the dominant process governing nighttime dispersion in the basin, while the nighttime dispersion in the Brush Creek valley is dominated by turbulent diffusion and plume confinement between the valley sidewalls. The interaction between valley flows and above ridgetops flows is investigated. A ventilation rate'' of material transport between the valley and above ridgetop flows is determined. This is important in regional air pollution modeling and global climate modeling. A simple model of dispersion in valleys, applicable through a diurnal cycle, is proposed.

Allwine, K.J.

1992-01-01T23:59:59.000Z

231

Atmospheric dispersion in mountain valleys and basins  

SciTech Connect (OSTI)

The primary goal of the research is to further characterize and understand dispersion in valley and basin atmospheres. A secondary, and related goal, is to identify and understand the dominant physical processes governing this dispersion. This has been accomplished through a review of the current literature, and analyses of recently collected data from two field experiments. This work should contribute to an improved understanding of material transport in the atmospheric boundary layer. It was found that dispersion in a freely draining valley (Brush Creek valley, CO) atmosphere is much greater than in an enclosed basin (Roanoke, VA) atmosphere primarily because of the greater wind speeds moving past the release point and the greater turbulence levels. The development of a cold air pool in the Roanoke basin is the dominant process governing nighttime dispersion in the basin, while the nighttime dispersion in the Brush Creek valley is dominated by turbulent diffusion and plume confinement between the valley sidewalls. The interaction between valley flows and above ridgetops flows is investigated. A ``ventilation rate`` of material transport between the valley and above ridgetop flows is determined. This is important in regional air pollution modeling and global climate modeling. A simple model of dispersion in valleys, applicable through a diurnal cycle, is proposed.

Allwine, K.J.

1992-01-01T23:59:59.000Z

232

HYPERsensarium : an archive of atmospheric conditions  

E-Print Network [OSTI]

HYPERsensarium proposes a tangible interface of atmospheres for public experience through an archive of historical and projected weathers. While architecture's purpose has long been to act as the technical boundary between ...

Shaw, Kelly E. (Kelly Evelyn)

2013-01-01T23:59:59.000Z

233

Humidity variations in the atmospheric surface layer  

E-Print Network [OSTI]

anemometer system used in this study, computed for five different wind speeds. 15 View from micrometeorologi cal tower towards the direction from which the wind was blowing for most of the runs select- ed. The left hand side is roughly 230' and the right... ASM Department of Meteorology by the Climatro- nics Corporation. The system consists of three sets of fast response wind, temperature, and relative humidity sensors, as well as a data acquisition system and a tape drive to store the data on magnetic...

Humphrey, Scott Richard

2012-06-07T23:59:59.000Z

234

Finite element analysis of shells with layers  

E-Print Network [OSTI]

It is well established that thin shell structures frequently feature narrow bands of strain concentration and localized displacement irregularities referred to as boundary and internal layers. It is crucial to capture these ...

Hiller, Jean-François, 1974-

2002-01-01T23:59:59.000Z

235

Atmospheric Neutrinos  

E-Print Network [OSTI]

This paper is a brief overview of the theory and experimental data of atmospheric neutrino production at the fiftieth anniversary of the experimental discovery of neutrinos.

Thomas K. Gaisser

2006-12-11T23:59:59.000Z

236

Convection induced by radiative cooling of a layer of participating medium  

SciTech Connect (OSTI)

Simulations and experiments have been conducted to study the effect of radiative cooling on natural convection in a horizontal layer of a participating medium enclosed between isothermal opaque wall and radiatively transparent wall and exposed to a cold background. The study is of relevance to a nocturnal boundary layer under clear and calm conditions. The focus of the study is to capture the onset of convection caused by radiative cooling. The experiments have been designed to mimic the atmospheric radiative boundary conditions, and hence decoupling convection and radiation boundary conditions. Planck number Pl and optical thickness of the layer ?{sub H} are the two important parameters that govern the interaction between radiation and convection. The radiation-convection coupling is a strong function of length scale. Convection sets up within first few seconds for all the experiments. Strong plume like convection is observed for the experimental conditions used in the present study. Both simulations and experiments confirm that radiative cooling increases substantially with decrease in emissivity of the bottom wall. Radiative cooling is strongly influenced by the nongray nature of the participating medium, especially when strong emission from the medium escapes to space, in the window region of the atmosphere. Accurate representation of radiative properties is critical. Linear stability analysis of onset of convection indicates that radiation stabilizes convection as Pl decreases. The observations are similar to the case of Rayleigh Bénard convection in a radiating gas. However, for both experimental and numerical conditions, the observed Rayleigh numbers are much greater than the critical Rayleigh number. To conclude, the role of radiation is to drive and sustain convection in the unstable layer.

Prasanna, Swaminathan, E-mail: prasannaswam@gmail.com [Laboratoire EM2C, CNRS UPR 288 92295, Chatenay-Malabry, France and Ecole Centrale Paris, Grande Voie des Vignes 92295, Chatenay-Malabry (France)] [Laboratoire EM2C, CNRS UPR 288 92295, Chatenay-Malabry, France and Ecole Centrale Paris, Grande Voie des Vignes 92295, Chatenay-Malabry (France); Venkateshan, S. P., E-mail: spv@iitm.ac.in [HTTP Laboratory, Department of Mechanical Engineering IIT Madras, Chennai (India)

2014-05-15T23:59:59.000Z

237

Improved Meteorological Input for Atmospheric Release Decision support Systems and an Integrated LES Modeling System for Atmospheric Dispersion of Toxic Agents: Homeland Security Applications  

SciTech Connect (OSTI)

When hazardous material is accidently or intentionally released into the atmosphere, emergency response organizations look to decision support systems (DSSs) to translate contaminant information provided by atmospheric models into effective decisions to protect the public and emergency responders and to mitigate subsequent consequences. The Department of Homeland Security (DHS)-led Interagency Modeling and Atmospheric Assessment Center (IMAAC) is one of the primary DSSs utilized by emergency management organizations. IMAAC is responsible for providing 'a single piont for the coordination and dissemination of Federal dispersion modeling and hazard prediction products that represent the Federal position' during actual or potential incidents under the National Response Plan. The Department of Energy's (DOE) National Atmospheric Release Advisory Center (NARAC), locatec at the Lawrence Livermore National Laboratory (LLNL), serves as the primary operations center of the IMAAC. A key component of atmospheric release decision support systems is meteorological information - models and data of winds, turbulence, and other atmospheric boundary-layer parameters. The accuracy of contaminant predictions is strongly dependent on the quality of this information. Therefore, the effectiveness of DSSs can be enhanced by improving the meteorological options available to drive atmospheric transport and fate models. The overall goal of this project was to develop and evaluate new meteorological modeling capabilities for DSSs based on the use of NASA Earth-science data sets in order to enhance the atmospheric-hazard information provided to emergency managers and responders. The final report describes the LLNL contributions to this multi-institutional effort. LLNL developed an approach to utilize NCAR meteorological predictions using NASA MODIS data for the New York City (NYC) region and demonstrated the potential impact of the use of different data sources and data parameterizations on IMAAC/NARAC fate and transport predictions. A case study involving coastal sea breeze circulation patterns in the NYC region was used to investigate the sensitivity of atmospheric dispersion results on the source of three-dimensional wind field data.

Arnold, E; Simpson, M; Larsen, S; Gash, J; Aluzzi, F; Lundquist, J; Sugiyama, G

2010-04-26T23:59:59.000Z

238

Compressed absorbing boundary conditions for the Helmholtz equation  

E-Print Network [OSTI]

Absorbing layers are sometimes required to be impractically thick in order to offer an accurate approximation of an absorbing boundary condition for the Helmholtz equation in a heterogeneous medium. It is always possible ...

Bélanger-Rioux, Rosalie

2014-01-01T23:59:59.000Z

239

Degenerate Metric Phase Boundaries  

E-Print Network [OSTI]

The structure of boundaries between degenerate and nondegenerate solutions of Ashtekar's canonical reformulation of Einstein's equations is studied. Several examples are given of such "phase boundaries" in which the metric is degenerate on one side of a null hypersurface and non-degenerate on the other side. These include portions of flat space, Schwarzschild, and plane wave solutions joined to degenerate regions. In the last case, the wave collides with a planar phase boundary and continues on with the same curvature but degenerate triad, while the phase boundary continues in the opposite direction. We conjecture that degenerate phase boundaries are always null.

Ingemar Bengtsson; Ted Jacobson

1999-01-23T23:59:59.000Z

240

Star-planet magnetic interaction and evaporation of planetary atmospheres  

E-Print Network [OSTI]

Stars interact with their close-in planets through radiation, gravitation, and magnetic fields. We investigate the energy input to a planetary atmosphere by reconnection between stellar and planetary magnetic fields and compare it to the energy input of the extreme ultraviolet (EUV) radiation field of the star. We quantify the power released by magnetic reconnection at the boundary of the planetary magnetosphere that is conveyed to the atmosphere by accelerated electrons. We introduce simple models to evaluate the energy spectrum of the accelerated electrons and the energy dissipated in the atmospheric layers in the polar regions of the planet upon which they impinge. A simple transonic isothermal wind flow along field lines is considered to estimate the increase in mass loss rate in comparison with a planet irradiated only by the EUV flux of its host star. We find that energetic electrons can reach levels down to column densities of 10^{23}-10^{25} m^{-2}, comparable with or deeper than EUV photons, and incr...

Lanza, A F

2013-01-01T23:59:59.000Z

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


241

The Method of Boundary Perturbation,  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 and NbSe2DifferentTheInforumLastProject:

242

PROPAGATION OF ALFVN WAVES AT THE PLASMA SHEET BOUNDARY Robert L. Lysak and Yan Song  

E-Print Network [OSTI]

PROPAGATION OF ALFVĂ?N WAVES AT THE PLASMA SHEET BOUNDARY LAYER Robert L. Lysak and Yan Song School conversion or by localized plasma flows in the tail. The generation and propagation of these waves is studied nonlinear MHD simulations of wave propagation at the boundary layer. INTRODUCTION Recent observations from

Lysak, Bob

243

Spectral behavior of the coupled land-atmosphere system  

E-Print Network [OSTI]

The main objective of this thesis is to understand the daily cycle of the energy coupling between the land and the atmosphere in response to a forcing of incoming radiation at their common boundary, the land surface. This ...

Gentine, Pierre

2010-01-01T23:59:59.000Z

244

Atmosphere Model  

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

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245

Boundaries and Topological Algorithms  

E-Print Network [OSTI]

This thesis develops a model for the topological structure of situations. In this model, the topological structure of space is altered by the presence or absence of boundaries, such as those at the edges of objects. ...

Fleck, Margaret Morrison

1988-09-01T23:59:59.000Z

246

Atmospheric Aerosol Systems | EMSL  

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

Science Themes Atmospheric Aerosol Systems Overview Atmospheric Aerosol Systems Biosystem Dynamics & Design Energy Materials & Processes Terrestrial & Subsurface Ecosystems...

247

The effect of tangential blowing on boundary-layer profiles  

E-Print Network [OSTI]

downstream of the slot. The width of the slot was set at 0. 013, 0. 033, and 0. 0415 inches. The blowing rates were varied to give a jet velocity of approximately 0, 163, 246, and 2 /5 feet per s cond. Results of the data are presented in graphical...; Blowing Rate Symbols B) B2 B 3 Cl C 2 C 3 D V (fps) J 163 246 2 75 163 246 275 163 Bjowing Rale (ft /sec) . 3 0. 0418 0. 0630 0. 0705 0. 1061 0. 1600 0. 1790 0. 1333 D D 3 246 275 0. 2013 0. 2250 A theory which expressed a...

Olson, Milford Eugene

1967-01-01T23:59:59.000Z

248

Computation of Hypersonic Double Wedge Shock / Boundary Layer Interaction  

E-Print Network [OSTI]

of a Scramjet Demonstrator for Future Space Transportation Systems" a combined numerical as well as experimental

249

ORIGINAL PAPER Mechanical filtering by the boundary layer and fluidstructure  

E-Print Network [OSTI]

force coefficient for fluid c speed of sound in water C integration constant Em Young's modulus of cupular matrix F stimulus frequency Fb buoyant force Fe elastic force Fm inertial force Fa acceleration

McHenry, Matt

250

Distributed Roughness Receptivity in a Flat Plate Boundary Layer  

E-Print Network [OSTI]

- Distributed Receptivity . . . . . 6 2. FACILITY DESCRIPTION - THE KLEBANOFF–SARIC WIND TUNNEL 11 2.1 Test Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.2 Fan and Motor... of this dissertation describes the Klebanoff–Saric Wind Tunnel facility, which was used for this experiment. Section 3 describes the experimental setup (roughness design and the flat plate model) and defines the metrics by which the flow field is decomposed...

Kuester, Matthew Scott

2014-04-18T23:59:59.000Z

251

Thermal boundary layer development in dispersed flow film boiling  

E-Print Network [OSTI]

Dispersed flow film boiling consists of a dispersion of droplets which are carried over a very hot surface by their vapor. This process occurs in cryogenic equipment and wet steam turbines. It is also of interest in the ...

Hull, Lawrence M.

1982-01-01T23:59:59.000Z

252

IMPACT OF BOUNDARY-LAYER CUTTING ON FREE-SURFACE  

E-Print Network [OSTI]

(FS) Open area ratio 37.1% 0.33 mm dia. wires w/open cell width of 0.51 mm (mesh size 30 � 30.7 cm ID) to rectangular cross-section 10 cm � 3 cm (y � z) · Perforated plate (PP) Open area ratio 50 area of liquid surface · Efficiency factor correlation (valid for Wed = 235­270,000) L mass flux

California at San Diego, University of

253

Control of cavity-driven separated boundary layer  

E-Print Network [OSTI]

and D. S. Henningson1 1 KTH Mechanics, S-100 44 Stockholm, Sweden 2 Laboratoire J.A. DieudonnŽe, Parc, like for instances the Tollmien-Schlichting waves on an aeroplane wing (see e.g. Hšogberg & Henningson, thanks to increasing computational power and the use of Arnoldi method (see Edwards et al. (1994

Hoepffner, JĂ©rĂŽme

254

DIRECT SIMULATION OF SPATIALLY EVOLVING COMPRESSIBLE TURBULENT BOUNDARY LAYERS  

E-Print Network [OSTI]

of the cold wall condition used in Ref. 6, and, other differences. The computational method used in this study compressible flows because of the interest in designing high speed vehicles and the associated propulsion on temperature. Under the adiabatic conditions of the experiment, the temperature increases as the wall

Erlebacher, Gordon

255

Control of the Transitional Boundary Layer Brandt A. Belson  

E-Print Network [OSTI]

in the presence of unmodeled disturbances. Next, we focus on a specific type of actuator, the single dielectric barrier discharge (SDBD) plasma actuator. An array of these plasma actuators is oriented to produce stream such that the controllers perform well when applied to the experiment. Lastly, we also simulate the plasma actuators

Rowley, Clarence W.

256

Supersonic turbulent boundary layers with periodic mechanical non-equilibrium  

E-Print Network [OSTI]

. It was documented that proper roughness selection coupled with a sufficiently strong favorable pressure gradient produced regions of ĂąÂ?Â?negativeĂąÂ? production in the transport of turbulent stress. This led to localized areas of significant turbulence stress...

Ekoto, Isaac Wesley

2007-04-25T23:59:59.000Z

257

THERMOPHORESIS OF PARTICLES IN A HEATED BOUNDARY LAYER  

E-Print Network [OSTI]

I (f) X Fig. 6 Reduced thermophoretic force as a function offrom the plate surface by thermophoretic forces. causing aseveral theories for the thermophoretic force. It was found

Talbot, L.

2012-01-01T23:59:59.000Z

258

Experimental and theoretical study of turbulent oscillatory boundary layers  

E-Print Network [OSTI]

Sediment transport is of crucial importance to engineering projects in coastal regions, so it is of primary interest in coastal engineering. The driving forces for sediment transport are mostly determined by the hydrodynamics ...

Yuan, Jing, Ph. D. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

259

absorbing boundary layers: Topics by E-print Network  

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

limits: (a) Pr>1, Pr1 and (b) Pr>>1. These two theoretical predictions are in excellent agreement with the results of our direct numerical simulations for Pr4.38 (water) and...

260

DIFFUSION OF A CHEMICAL SPECIES THROUGH A VISCOUS BOUNDARY LAYER  

E-Print Network [OSTI]

use an operating coal gasifier will be discussed. ofof the products of the gasifier with H S removed, then theconditions existing in coal gasifiers the con- centration

Keller, J.

2011-01-01T23:59:59.000Z

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


261

ARM - PI Product - Planetary Boundary Layer from AERI and MPL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc Documentation RUC : XDCResearchWarmingMethaneProductsCSSEFProductsMerged andAerosol

262

ARM - Field Campaign - Boundary Layer CO2 Using CW Lidar  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience4AJ01)3,Cloud OD Sensor TWST Cloud OD Sensor

263

A dual mass flux framework for boundary layer convection  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience hands-onASTROPHYSICSHeResearchcharm that has beenA dual mass

264

Large-Scale Streamwise Turbulent Structures in Hypersonic Boundary Layers  

E-Print Network [OSTI]

13 Before and after example of pre-processed images........................... 27 14 Average velocity and TKE comparison ............................................ 37 15 Reynolds shear stress comparison... 19 Instantaneous velocity field comparison at ? ..................... 42 20 Instantaneous velocity field comparison at ? ..................... 44 21 Instantaneous velocity field comparison at ? ..................... 45...

English, Benjamin L.

2013-04-22T23:59:59.000Z

265

Transgressing the Boundaries: An Afterword  

E-Print Network [OSTI]

the Boundaries: Toward a Transformative Hermeneutics of Quantum Gravity'', which appeared in Social Text #46

Sokal, Alan

266

3D convection simulations of the outer layers of the Sun using realistic physics  

E-Print Network [OSTI]

This paper describes a series of 3D simulations of shallow inefficient convection in the outer layers of the Sun. The computational domain is a closed box containing the convection-radiation transition layer, located at the top of the solar convection zone. The most salient features of the simulations are that: i)The position of the lower boundary can have a major effect on the characteristics of solar surface convection (thermal structure, kinetic energy and turbulent pressure). ii)The width of the box has only a minor effect on the thermal structure, but a more significant effect on the dynamics (rms velocities). iii)Between the surface and a depth of 1 Mm, even though the density and pressure increase by an order of magnitude, the vertical correlation length of vertical velocity is always close to 600 km. iv) In this region the vertical velocity cannot be scaled by the pressure or the density scale height. This casts doubt on the applicability of the mixing length theory, not only in the superadiabatic layer, but also in the adjacent underlying layers. v) The final statistically steady state is not strictly dependent on the initial atmospheric stratification.

F. J. Robinson; P. Demarque; L. H. Li; S. Sofia; Y. -C. Kim; K. L. Chan; D. B. Guenther

2002-12-12T23:59:59.000Z

267

Boundary Plasma Turbulence Simulations for Tokamaks  

SciTech Connect (OSTI)

The boundary plasma turbulence code BOUT models tokamak boundary-plasma turbulence in a realistic divertor geometry using modified Braginskii equations for plasma vorticity, density (ni), electron and ion temperature (T{sub e}; T{sub i}) and parallel momenta. The BOUT code solves for the plasma fluid equations in a three dimensional (3D) toroidal segment (or a toroidal wedge), including the region somewhat inside the separatrix and extending into the scrape-off layer; the private flux region is also included. In this paper, a description is given of the sophisticated physical models, innovative numerical algorithms, and modern software design used to simulate edge-plasmas in magnetic fusion energy devices. The BOUT code's unique capabilities and functionality are exemplified via simulations of the impact of plasma density on tokamak edge turbulence and blob dynamics.

Xu, X; Umansky, M; Dudson, B; Snyder, P

2008-05-15T23:59:59.000Z

268

Field measurement of the fate of atmospheric H? in a forest environment : from canopy to soil  

E-Print Network [OSTI]

Atmospheric hydrogen (H? ), an indirect greenhouse gas, plays a notable role in the chemistry of the atmosphere and ozone layer. Current anthropogenic emissions of H? are substantial and may increase with its widespread ...

Meredith, Laura Kelsey, 1982-

2013-01-01T23:59:59.000Z

269

Wavelet analysis study of microbubble drag reduction in a boundary channel flow  

E-Print Network [OSTI]

Particle Image Velocimetry (PIV) and pressure measurement techniques were performed to investigate the drag reduction due to microbubble injection in the boundary layer of a fully developed turbulent channel flow. Two-dimensional full-field velocity...

Zhen, Ling

2006-04-12T23:59:59.000Z

270

Boundary transfer matrices and boundary quantum KZ equations  

E-Print Network [OSTI]

A simple relation between inhomogeneous transfer matrices and boundary quantum KZ equations is exhibited for quantum integrable systems with reflecting boundary conditions, analogous to an observation by Gaudin for periodic systems. Thus the boundary quantum KZ equations receive a new motivation. We also derive the commutativity of Sklyanin's boundary transfer matrices by merely imposing appropriate reflection equations, i.e. without using the conditions of crossing symmetry and unitarity of the R-matrix.

Bart Vlaar

2014-10-31T23:59:59.000Z

271

Interface dynamics for layered structures  

E-Print Network [OSTI]

We investigate dynamics of large scale and slow deformations of layered structures. Starting from the respective model equations for a non-conserved system, a conserved system and a binary fluid, we derive the interface equations which are a coupled set of equations for deformations of the boundaries of each domain. A further reduction of the degrees of freedom is possible for a non-conserved system such that internal motion of each domain is adiabatically eliminated. The resulting equation of motion contains only the displacement of the center of gravity of domains, which is equivalent to the phase variable of a periodic structure. Thus our formulation automatically includes the phase dynamics of layered structures. In a conserved system and a binary fluid, however, the internal motion of domains turns out to be a slow variable in the long wavelength limit because of concentration conservation. Therefore a reduced description only involving the phase variable is not generally justified.

Takao Ohta; David Jasnow

1997-07-17T23:59:59.000Z

272

Boundary unitarity without firewalls  

E-Print Network [OSTI]

Both AdS/CFT duality and more general reasoning from quantum gravity point to a rich collection of boundary observables that always evolve unitarily. The physical quantum gravity states described by these observables must be solutions of the spatial diffeomorphism and Wheeler-deWitt constraints, which implies that the state space does not factorize into a tensor product of localized degrees of freedom. The "firewall" argument that unitarity of black hole S-matrix implies the presence of a highly excited quantum state near the horizon is based on such a factorization, hence is not applicable in quantum gravity. In fact, there appears to be no conflict between boundary unitarity and regularity of the event horizon.

Ted Jacobson

2014-03-23T23:59:59.000Z

273

Energy transport, overshoot, and mixing in the atmospheres of very cool stars  

E-Print Network [OSTI]

We constructed hydrodynamical model atmospheres for mid M-type main-, as well as pre-main-sequence objects. Despite the complex chemistry encountered in such cool atmospheres a reasonably accurate representation of the radiative transfer is possible. The detailed treatment of the interplay between radiation and convection in the hydrodynamical models allows to study processes usually not accessible within the framework conventional model atmospheres. In particular, we determined the efficiency of the convective energy transport, and the efficiency of mixing by convective overshoot. The convective transport efficiency expressed in terms of an equivalent mixing-length parameter amounts to values around ~2 in the optically thick, and ~2.8 in the optically thin regime. The thermal structure of the formally convectively stable layers is little affected by convective overshoot and wave heating, i.e. stays close to radiative equilibrium. Mixing by convective overshoot shows an exponential decline with geometrical distance from the Schwarzschild stability boundary. The scale height of the decline varies with gravitational acceleration roughly as g^(-1/2), with 0.5 pressure scale heights at log(g)=5.0.

H. -G. Ludwig

2002-08-30T23:59:59.000Z

274

Gas-surface interaction and boundary conditions for the Boltzmann equation  

E-Print Network [OSTI]

Gas-surface interaction and boundary conditions for the Boltzmann equation StÂŽephane Brull, Pierre Equation. The interaction between the wall atoms and the gas molecules within a thin surface layer of the gas in the bulk flow. Boundary conditions are formally derived from this model by using classical

Mieussens, Luc

275

Combined influence of atmospheric physics and soil hydrology on the simulated meteorology at the SIRTA atmospheric  

E-Print Network [OSTI]

for This paper is a contribution to the special issue on the IPSL and CNRM global climate and Earth System Models it to evaluate the standard and new parametrizations of boundary layer/convection/clouds in the Earth System Model (ESM) of Institut Pierre Simon Laplace (IPSL), which differentiate the IPSL-CM5A and IPSL- CM5B

Hourdin, Chez Frédéric

276

DOE Workshop; Pan-Gass Conference on the Representation of Atmospheric Processes in Weather and Climate Models  

SciTech Connect (OSTI)

This is the first meeting of the whole new GEWEX (Global Energy and Water Cycle Experiment) Atmospheric System Study (GASS) project that has been formed from the merger of the GEWEX Cloud System Study (GCSS) Project and the GEWEX Atmospheric Boundary Layer Studies (GABLS). As such, this meeting will play a major role in energizing GEWEX work in the area of atmospheric parameterizations of clouds, convection, stable boundary layers, and aerosol-cloud interactions for the numerical models used for weather and climate projections at both global and regional scales. The representation of these processes in models is crucial to GEWEX goals of improved prediction of the energy and water cycles at both weather and climate timescales. This proposal seeks funds to be used to cover incidental and travel expenses for U.S.-based graduate students and early career scientists (i.e., within 5 years of receiving their highest degree). We anticipate using DOE funding to support 5-10 people. We will advertise the availability of these funds by providing a box to check for interested participants on the online workshop registration form. We will also send a note to our participants' mailing lists reminding them that the funds are available and asking senior scientists to encourage their more junior colleagues to participate. All meeting participants are encouraged to submit abstracts for oral or poster presentations. The science organizing committee (see below) will base funding decisions on the relevance and quality of these abstracts, with preference given to under-represented populations (especially women and minorities) and to early career scientists being actively mentored at the meeting (e.g. students or postdocs attending the meeting with their advisor).

Morrison, PI Hugh

2012-09-21T23:59:59.000Z

277

Boundaries on Spacetimes: An Outline  

E-Print Network [OSTI]

The causal boundary construction of Geroch, Kronheimer, and Penrose has some universal properties of importance for general studies of spacetimes, particularly when equipped with a topology derived from the causal structure. Properties of the causal boundary are detailed for spacetimes with spacelike boundaries, for multi-warped spacetimes, for static spacetimes, and for spacetimes with group actions.

Steven G. Harris

2003-10-15T23:59:59.000Z

278

Topology of the Future Chronological Boundary: Universality for Spacelike Boundaries  

E-Print Network [OSTI]

A method is presented for imputing a topology for any chronological set, i.e., a set with a chronology relation, such as a spacetime or a spacetime with some sort of boundary. This topology is shown to have several good properties, such as replicating the manifold topology for a spacetime and replicating the expected topology for some simple examples of spacetime-with-boundary; it also allows for a complete categorical characterization, in topological categories, of the Future Causal Boundary construction of Geroch, Kronheimer, and Penrose, showing that construction to have a universal property for future-completing chronological sets with spacelike boundaries. Rigidity results are given for any reasonable future completion of a spacetime, in terms of the GKP boundary: In the imputed topology, any such boundary must be homeomorphic to the GKP boundary (if all points have indecomposable pasts) or to a topological quotient of a closely related boundary (if boundaries are spacelike). A large class of warped-product-type spacetimes with spacelike boundaries is examined, calculating the GKP and other possible boundaries, and showing that the imputed topology gives expected results; included among these are the Schwarzschild singularity and those Robertson-Walker singularities which are spacelike.

Steven G. Harris

1999-07-19T23:59:59.000Z

279

Turn-key Raman lidar for profiling atmospheric water vapor, clouds, and aerosols at the US Southern Great Plains Climate Study Site  

SciTech Connect (OSTI)

There are clearly identified scientific requirements for continuous profiling of atmospheric water vapor at the Department of Energy, Atmospheric Radiation Measurement program, Southern Great Plains CART (Cloud and Radiation Testbed) site in northern Oklahoma. Research conducted at several laboratories has demonstrated the suitability of Raman lidar for providing measurements that are an excellent match to those requirements. We have developed and installed a ruggedized Raman lidar system that resides permanently at the CART site, and that is computer automated to eliminate the requirements for operator interaction. In addition to the design goal of profiling water vapor through most of the troposphere during nighttime and through the boundary layer during daytime, the lidar provides quantitative characterizations of aerosols and clouds, including depolarization measurements for particle phase studies.

Goldsmith, J.E.M.; Blair, F.H.; Bisson, S.E.

1997-12-31T23:59:59.000Z

280

Building biomedical materials layer-by-layer  

E-Print Network [OSTI]

In this materials perspective, the promise of water based layer-by-layer (LbL) assembly as a means of generating drug-releasing surfaces for biomedical applications, from small molecule therapeutics to biologic drugs and ...

Hammond, Paula T.

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


281

Surface Temperature and Surface-Layer Turbulence in a Convective Boundary Layer  

E-Print Network [OSTI]

are density, specific heat of the soil, and grid size in theThe ground heat-flux G then computed from T g as grid was

Garai, Anirban; Pardyjak, Eric; Steeneveld, Gert-Jan; Kleissl, Jan

2013-01-01T23:59:59.000Z

282

Surface Temperature and Surface-Layer Turbulence in a Convective Boundary Layer  

E-Print Network [OSTI]

The vertical gradient of horizontal wind-speed was estimateda larger vertical gradient of horizontal wind-speed in thewind speed, direction, temperature, humidity up to 20 km with a vertical

Garai, Anirban; Pardyjak, Eric; Steeneveld, Gert-Jan; Kleissl, Jan

2013-01-01T23:59:59.000Z

283

ARM - SGP Boundary Facility  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc Documentation RUC :ProductsSCM Forcing Data DerivedInstrumentsPolar YearResearchBoundary

284

ECMWF workshop on Ocean-Atmosphere Interactions, 10-12 Nov 2008 A revised ocean-atmosphere  

E-Print Network [OSTI]

interface #12;1*- Sensible heat flux 6*- Evaporation + int. energy [+ Qlat] ECMWF workshop on Ocean layer) 5- Surface ocean current 7- Surface height 7 1- Continental runoff + internal Energy 8 1*- SurfECMWF workshop on Ocean-Atmosphere Interactions, 10-12 Nov 2008 A revised ocean-atmosphere physical

285

Morris Boundary Facility  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment SurfacesResource ProgramModification andinterface1 E n e r2Adsorption of

286

Purcell Boundary Facility  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedlesAdvancedJanuary 13, 2011Portal Energy For

287

Climate Sciences: Atmospheric Thermodynamics  

E-Print Network [OSTI]

1 Climate Sciences: Atmospheric Thermodynamics Instructor: Lynn Russell, NH343 http://aerosol.ucsd.edu/courses.html Text: Curry & Webster Atmospheric Thermodynamics Ch1 Composition Ch2 Laws Ch3 Transfers Ch12 Energy Climate Sciences: Atmospheric Thermodynamics Instructor: Lynn Russell, NH343 http

Russell, Lynn

288

5, 60416076, 2005 Atmospheric  

E-Print Network [OSTI]

opportunity to examine atmospheric oxidation in a megacity that has more pollution than typical USACPD 5, 6041­6076, 2005 Atmospheric oxidation in the Mexico City Metropolitan Area T. R. Shirley et.atmos-chem-phys.org/acpd/5/6041/ SRef-ID: 1680-7375/acpd/2005-5-6041 European Geosciences Union Atmospheric Chemistry

Boyer, Edmond

289

The Atmospheric Radiation Measurement Program Video  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 and NbSe2 .2004The Atmospheric Radiation Measurement

290

2. System boundaries; Balance equations  

E-Print Network [OSTI]

;5/28 Systems and boundaries /3 An isolated system is a special kind of closed system Pictures: KJ05 Q = heat W Example: an electric hot water heater in a house ­ The electric heater is a closed system ­ The water1/28 2. System boundaries; Balance equations Ron Zevenhoven �bo Akademi University Thermal and flow

Zevenhoven, Ron

291

Comparison of atmospheric hydrology over convective continental regions using water vapor isotope measurements from space  

E-Print Network [OSTI]

. Correlation analysis shows that mixing with boundary layer air, enhanced isotopic fractionation during precipitation, and subsiding air parcels contribute to intraseasonal isotopic variability. These local controls distillation in a Lagrangrian framework underestimates the observed isotopic depletion during the monsoons

292

VALDRIFT 1.0: A valley atmospheric dispersion model with deposition  

SciTech Connect (OSTI)

VALDRIFT version 1.0 is an atmospheric transport and diffusion model for use in well-defined mountain valleys. It is designed to determine the extent of ddft from aedal pesticide spraying activities, but can also be applied to estimate the transport and diffusion of various air pollutants in valleys. The model is phenomenological -- that is, the dominant meteorological processes goveming the behavior of the valley atmosphere are formulated explicitly in the model, albeit in a highly parameterized fashion. The key meteorological processes treated are: (1) nonsteady and nonhomogeneous along-valley winds and turbulent diffusivities, (2) convective boundary layer growth, (3) inversion descent, (4) noctumal temperature inversion breakup, and (5) subsidence. The model is applicable under relatively cloud-free, undisturbed synoptic conditions and is configured to operate through one diumal cycle for a single valley. The inputs required are the valley topographical characteristics, pesticide release rate as a function of time and space, along-valley wind speed as a function of time and space, temperature inversion characteristics at sunrise, and sensible heat flux as a function of time following sunrise. Default values are provided for certain inputs in the absence of detailed observations. The outputs are three-dimensional air concentration and ground-level deposition fields as a function of time.

Allwine, K.J.; Bian, X.; Whiteman, C.D.

1995-05-01T23:59:59.000Z

293

A New Ensemble of Perturbed-Input-Parameter Simulations by the Community Atmosphere Model  

SciTech Connect (OSTI)

Uncertainty quantification (UQ) is a fundamental challenge in the numerical simulation of Earth's weather and climate, and other complex systems. It entails much more than attaching defensible error bars to predictions: in particular it includes assessing low-probability but high-consequence events. To achieve these goals with models containing a large number of uncertain input parameters, structural uncertainties, etc., raw computational power is needed. An automated, self-adapting search of the possible model configurations is also useful. Our UQ initiative at the Lawrence Livermore National Laboratory has produced the most extensive set to date of simulations from the US Community Atmosphere Model. We are examining output from about 3,000 twelve-year climate simulations generated with a specialized UQ software framework, and assessing the model's accuracy as a function of 21 to 28 uncertain input parameter values. Most of the input parameters we vary are related to the boundary layer, clouds, and other sub-grid scale processes. Our simulations prescribe surface boundary conditions (sea surface temperatures and sea ice amounts) to match recent observations. Fully searching this 21+ dimensional space is impossible, but sensitivity and ranking algorithms can identify input parameters having relatively little effect on a variety of output fields, either individually or in nonlinear combination. Bayesian statistical constraints, employing a variety of climate observations as metrics, also seem promising. Observational constraints will be important in the next step of our project, which will compute sea surface temperatures and sea ice interactively, and will study climate change due to increasing atmospheric carbon dioxide.

Covey, C; Brandon, S; Bremer, P T; Domyancis, D; Garaizar, X; Johannesson, G; Klein, R; Klein, S A; Lucas, D D; Tannahill, J; Zhang, Y

2011-10-27T23:59:59.000Z

294

AtmosphericAtmospheric Composition Introduction The division investigates the atmospheric  

E-Print Network [OSTI]

development on observation side was the installation of an ozone observation station in Surinam in close co-operation with the Surinam Meteorological Service. Processes in the tropical regions are important for the global climate and the global atmospheric composition. The participation in Indoex (Indian Ocean Experiment) and this Surinam

Haak, Hein

295

Internal wave and boundary current generation by tidal flow over topography Amadeus Dettner, Harry L. Swinney, and M. S. Paoletti  

E-Print Network [OSTI]

.1063/1.4808163 Negative turbulent production during flow reversal in a stratified oscillating boundary layer on a sloping of Texas at Austin, Austin, Texas 78712, USA (Received 31 May 2013; accepted 10 October 2013; published of a uniformly stratified fluid. The radiated power PIW and kinetic energy density of the boundary currents

Texas at Austin. University of

296

Toward a Diurnal Climatology of Cold-Season Turbulence Statistics in Continental Stratocumulus as Observed by the Atmospheric Radiation Millimeter- Wavelength Cloud Radars  

SciTech Connect (OSTI)

Numerous observational studies of marine stratocumulus have demonstrated a pronounced diurnal cycle. At night, longwave flux divergence at the top of the cloud drives negatively buoyant eddies that tend to keep the boundary layer well mixed. During the day, solar absorption by the cloud tends to reduce the turbulent intensity and often decouples the planetary boundary layer (PBL) into cloud- and sub-cloud circulations. The delicate balance between turbulent intensity, entrainment, and fluxes dictates cloud geometry and persistence, which can significantly impact the shortwave radiation budget. Millimeter-wavelength cloud radars (MMCRs) have been used to study the turbulent structure of boundary layer stratocumulus (e.g. Frisch et al. 1995; Kollias and Albrecht 2000). Analysis is confined to nondrizzling or lightly drizzling cloud systems for which precipitation contamination is negligible. Under such assumptions the Doppler velocity field becomes a proxy for vertical velocity. Prior research has mainly consisted of a few case studies of specific cloud systems using radar scan strategies optimized for this particular cloud type. The MMCR operating at the Southern Great Plains Atmospheric Radiation Measurement Climate Research Facility is broadly configured to be able to detect many different cloud types over a broad range of reflectivities and altitudes, so it is not specifically optimized for PBL clouds. Being in more-or-less continuous operation since the end of 1996, it does, however, have the advantage of long data coverage, which suggests that statistically significant measures of the diurnal cycle of turbulence should be attainable. This abstract summarizes the first few steps toward this goal, using 7 months of cold season MMCR data.

Mechem, D.B.; Kogan, Y.L.; Childers, M.E.; Donner, K.M.

2005-03-18T23:59:59.000Z

297

Overturning and wind driven circulation in a low-order ocean-atmosphere model  

E-Print Network [OSTI]

july 2002 Abstract A low-order ocean-atmosphere model is presented which combines coupling through heat exchange at the interface and wind stress forcing. The coupling terms are derived from the boundary conditions and the forcing terms of the constituents. Both the ocean and the atmosphere model are based

van Veen, Lennaert

298

A perfectly matched layer formulation for the nonlinear shallow water equations models: The split  

E-Print Network [OSTI]

In a limited-area numerical weather prediction model, the lateral boundaries are not physical boundaries interest since the early days of numerical weather prediction. Several good reviews are availableA perfectly matched layer formulation for the nonlinear shallow water equations models: The split

Navon, Michael

299

Atmospheric Neutrino Fluxes  

E-Print Network [OSTI]

Starting with an historical review, I summarize the status of calculations of the flux of atmospheric neutrinos and how they compare to measurements.

Thomas K. Gaisser

2005-02-18T23:59:59.000Z

300

South Campus Boundary/Landscape  

E-Print Network [OSTI]

South Campus Boundary/Landscape April 18, 2012 #12;#12;7:00 - 7:05 Introductions and Review of the Agenda 7:05 - 7:20 Principles of the South Campus Boundary/Landscape from the Feb 21 Design Charette 7:20 - 7:30 Landscape Examples 7:30 - 7:45 Concepts and Ideas for LeMarchant St. 7:45 - 7:50 Break

Brownstone, Rob

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


301

Changing the Structure Boundary Geometry  

SciTech Connect (OSTI)

Analysis of previously obtained results shows that hexagonal crystal lattice is the dominant type of ordering, in particular, in striated glow discharges. We explore the possibility for changing the dust distribution in horizontal cross sections of relatively highly ordered structures in a glow-discharge. Presuming that boundary geometry can affect dust distribution, we used cylindrical coolers held at 0 deg. C and placed against a striation containing a structure, to change the geometry of its outer boundary. By varying the number of coolers, their positions, and their separations from the tube wall, azimuthally asymmetric thermophoretic forces can be used to form polygonal boundaries and vary the angles between their segments (in a horizontal cross section). The corner in the structure's boundary of 60 deg. stimulates formation of hexagonal cells. The structure between the supported parallel boundaries is also characterized by stable hexagonal ordering. We found that a single linear boundary segment does not give rise to any sizable domain, but generates a lattice extending from the boundary (without edge defects). A square lattice can be formed by setting the angle equal to 90 deg. . However, angles of 45 deg. and 135 deg. turned out easier to form. Square lattice was created by forming a near-135 deg. corner with four coolers. It was noted that no grain ordering is observed in the region adjacent to corners of angles smaller than 30 deg. , which do not promote ordering into cells of any shape. Thus, manipulation of a structure boundary can be used to change dust distribution, create structures free of the ubiquitous edge defects that destroy orientation order, and probably change the crystal lattice type.

Karasev, Viktor; Dzlieva, Elena; Ivanov, Artyom [St.-Petersburg State University, Physics Faculty, Ulianovskaya 1, Peterhof, St. Petersburg, 198504 (Russian Federation)

2008-09-07T23:59:59.000Z

302

ON THE ACOUSTIC SINGLE LAYER POTENTIAL: STABILIZATION AND FOURIER ANALYSIS  

E-Print Network [OSTI]

ON THE ACOUSTIC SINGLE LAYER POTENTIAL: STABILIZATION AND FOURIER ANALYSIS A. BUFFA AND S. SAUTER in the stability and convergence estimates attains its minumum. Key words. Acoustic scattering, Galerkin boundary discretizations for the Helmholtz problem suffer from the pollution effect, i.e., the constants in the Galerkin

Buffa, Annalisa

303

Synergistic Effects of Turbine Wakes and Atmospheric Stability on Power Production at an Onshore Wind Farm  

SciTech Connect (OSTI)

This report examines the complex interactions between atmospheric stability and turbine-induced wakes on downwind turbine wind speed and power production at a West Coast North American multi-MW wind farm. Wakes are generated when the upwind flow field is distorted by the mechanical movement of the wind turbine blades. This has two consequences for downwind turbines: (1) the downwind turbine encounters wind flows with reduced velocity and (2) the downwind turbine encounters increased turbulence across multiple length scales via mechanical turbulence production by the upwind turbine. This increase in turbulence on top of ambient levels may increase aerodynamic fatigue loads on the blades and reduce the lifetime of turbine component parts. Furthermore, ambient atmospheric conditions, including atmospheric stability, i.e., thermal stratification in the lower boundary layer, play an important role in wake dissipation. Higher levels of ambient turbulence (i.e., a convective or unstable boundary layer) lead to higher turbulent mixing in the wake and a faster recovery in the velocity flow field downwind of a turbine. Lower levels of ambient turbulence, as in a stable boundary layer, will lead to more persistent wakes. The wake of a wind turbine can be divided into two regions: the near wake and far wake, as illustrated in Figure 1. The near wake is formed when the turbine structure alters the shape of the flow field and usually persists one rotor diameter (D) downstream. The difference between the air inside and outside of the near wake results in a shear layer. This shear layer thickens as it moves downstream and forms turbulent eddies of multiple length scales. As the wake travels downstream, it expands depending on the level of ambient turbulence and meanders (i.e., travels in non-uniform path). Schepers estimates that the wake is fully expanded at a distance of 2.25 D and the far wake region begins at 2-5 D downstream. The actual distance traveled before the wake recovers to its inflow velocity is dependent on the amount ambient turbulence, the amount of wind shear, and topographical and structural effects. The maximum velocity deficit is estimated to occur at 1-2 D but can be longer under low levels of ambient turbulence. Our understanding of turbine wakes comes from wind tunnel experiments, field experiments, numerical simulations, and from studies utilizing both experimental and modeling methods. It is well documented that downwind turbines in multi-Megawatt wind farms often produce less power than upwind turbine rows. These wake-induced power losses have been estimated from 5% to up to 40% depending on the turbine operating settings (e.g., thrust coefficient), number of turbine rows, turbine size (e.g., rotor diameter and hub-height), wind farm terrain, and atmospheric flow conditions (e.g., ambient wind speed, turbulence, and atmospheric stability). Early work by Elliott and Cadogan suggested that power data for different turbulent conditions be segregated to distinguish the effects of turbulence on wind farm power production. This may be especially important for downwind turbines within wind farms, as chaotic and turbulent wake flows increase stress on downstream turbines. Impacts of stability on turbine wakes and power production have been examined for a flat terrain, moderate size (43 turbines) wind farm in Minnesota and for an offshore, 80 turbine wind farm off the coast of Denmark. Conzemius found it difficult to distinguish wakes (i.e., downwind velocity deficits) when the atmosphere was convective as large amounts of scatter were present in the turbine nacelle wind speed data. This suggested that high levels of turbulence broke-up the wake via large buoyancy effects, which are generally on the order of 1 km in size. On the other hand, they found pronounced wake effects when the atmosphere was very stable and turbulence was either suppressed or the length scale was reduced as turbulence in this case was mechanically produced (i.e., friction forces). This led to larger reductions at downwind turbines and maximum ve

Wharton, S; Lundquist, J K; Marjanovic, N

2012-01-25T23:59:59.000Z

304

Atmospheric Thermodynamics Composition  

E-Print Network [OSTI]

1 Atmospheric Thermodynamics Ch1 Composition Ch2 Laws Ch3 Transfers Ch12 EnergyBalance Ch4 Water Ch Sciences: Atmospheric Thermodynamics Instructor: Lynn Russell, NH343 http #12;2 Review from Ch. 1 · Thermodynamic quantities · Composition · Pressure · Density · Temperature

Russell, Lynn

305

Atmospheric Dynamics II Instructor  

E-Print Network [OSTI]

AT602 Atmospheric Dynamics II 2 credits Instructor: David W. J. Thompson davet: An Introduction to Dynamic Meteorology, 5th Edition, Academic Press (recommended) · Marshall, J., and Plumb, R. A., 2008: Atmosphere, Ocean, and Climate Dynamics: An Introductory Text, Academic Press. · Vallis, G. K

306

Electric Field in a Double Layer and the Imparted Momentum  

SciTech Connect (OSTI)

It is shown that the net momentum delivered by the large electric field inside a one-dimensional double layer is zero. This is demonstrated through an analysis of the momentum balance in the double layer at the boundary between the ionosphere and the aurora cavity. For the recently observed double layer in a current-free plasma expanding along a divergent magnetic field, an analysis of the evolution of the radially averaged variables shows that the increase of plasma thrust results from the magnetic-field pressure balancing the plasma pressure in the direction of acceleration, rather than from electrostatic pressure.

Fruchtman, A. [Holon Academic Institute of Technology, 52 Golomb Street, Holon 58102 (Israel)

2006-02-17T23:59:59.000Z

307

Layered plasma polymer composite membranes  

DOE Patents [OSTI]

Layered plasma polymer composite fluid separation membranes are disclosed, which comprise alternating selective and permeable layers for a total of at least 2n layers, where n is [>=]2 and is the number of selective layers. 2 figs.

Babcock, W.C.

1994-10-11T23:59:59.000Z

308

A bridging technique to analyze the influence of boundary conditions on instability patterns  

SciTech Connect (OSTI)

In this paper, we present a new numerical technique that permits to analyse the effect of boundary conditions on the appearance of instability patterns. Envelope equations of Landau-Ginzburg type are classically used to predict pattern formation, but it is not easy to associate boundary conditions for these macroscopic models. Indeed, envelope equations ignore boundary layers that can be important, for instance in cases where the instability starts first near the boundary. In this work, the full model is considered close to the boundary, an envelope equation in the core and they are bridged by the Arlequin method . Simulation results are presented for the problem of buckling of long beams lying on a non-linear elastic foundation.

Hu Heng, E-mail: huheng@whu.edu.c [School of Civil Engineering, Wuhan University, 8 South Road of East Lake, 430072 Wuhan (China); Damil, Noureddine, E-mail: noureddine.damil@gmail.co [Laboratoire de Calcul Scientifique en Mecanique, Faculte des Sciences Ben M'Sik, Universite Hassan II Mohammedia-Casablanca, Sidi Othman, Casablanca (Morocco); Potier-Ferry, Michel, E-mail: michel.potierferry@univ-metz.f [Laboratoire d'Etude des Microstructures et de Mecanique des Materiaux, LEM3, UMR CNRS 7239, Universite Paul Verlaine-Metz, Ile du Saulcy, 57045 Metz Cedex 01 (France)

2011-05-10T23:59:59.000Z

309

Layered Cathode Materials  

Broader source: Energy.gov (indexed) [DOE]

Layered Cathode Materials presented by Michael Thackeray Chemical Sciences and Engineering Division, Argonne Annual Merit Review DOE Vehicle Technologies Program Washington, D.C....

310

Cross-Layer Attack and Defense in Cognitive Radio Networks Wenkai Wang and Yan (Lindsay) Sun  

E-Print Network [OSTI]

Cross-Layer Attack and Defense in Cognitive Radio Networks Wenkai Wang and Yan (Lindsay) Sun ECE research on security issues in cognitive radio networks mainly focuses on attack and defense in individual network layers. However, the attackers do not necessarily restrict themselves within the boundaries

Sun, Yan Lindsay

311

Atmospheric Pollution Research 1 (2010) 220228 Atmospheric Pollution Research  

E-Print Network [OSTI]

Atmospheric Pollution Research 1 (2010) 220228 Atmospheric Pollution Research www in modeling of the associated multiphase processes. Iron redox species are important pollutants. The oxidative capacity of the atmospheric cloud water decreases when dissolution is included

Boyer, Edmond

312

Computer Modeling of Transport of Oxidizing Species in Grain Boundaries during Zirconium Corrosion  

SciTech Connect (OSTI)

Zirconium (Zr) based alloys are widely used as the cladding materials in light-water reactors. The water-side corrosion of these alloys degrades their structural integrity and poses serious safety concerns. During the Zr corrosion process, a thin Zr oxide (ZrO2) layer forms on the alloy surface and serves as a barrier layer for further corrosion. The majority of the oxide has the monoclinic phase. At the transition region between the oxide and the metal, the oxide contains a thin layer of stabilized tetragonal phase. It is found that the texture of the tetragonal layer determines the protectiveness of the oxide for corrosion. The transport of oxidizing species, such as anion defects, cation defects, and electron through the tetragonal oxide layer could be the rate limiting step of the corrosion. The defect diffusion can be affected by the growing stresses and microstructures such as grain boundaries and dislocations. In this work molecular dynamics simulations are used to investigate the anion and cation diffusion in bulk and at grain boundaries in tetragonal ZrO2. The results show that defect diffusion at grain boundaries is complex and the behavior strongly depends on the grain boundary type. For most of the grain boundaries studied the defect diffusion are much slower than in the bulk, implying that grain boundaries may not be fast defect transport paths during corrosion. The connection between the modeling results and published experimental work will also be discussed. This work is funded by the Laboratory Directed Research and Development (LDRD) program at Idaho National Laboratory.

Xian-Ming Bai; Yongfeng Zhang; Michael R. Tonks

2014-06-01T23:59:59.000Z

313

Layering as Optimization Decomposition 3-1 Layering as OptimizationLayering as Optimization  

E-Print Network [OSTI]

1 Layering as Optimization Decomposition 3-1 Layering as OptimizationLayering as Optimization DecompositionDecomposition Layering as Optimization Decomposition 3-2 CONTENTSCONTENTS Introduction (Marta;2 Layering as Optimization Decomposition 3-3 Layering as Optimization Decomposition Introduction By Marta

Fan, Xingzhe

314

Atmospheric optical calibration system  

DOE Patents [OSTI]

An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions. 7 figs.

Hulstrom, R.L.; Cannon, T.W.

1988-10-25T23:59:59.000Z

315

Multiple density layered insulator  

DOE Patents [OSTI]

A multiple density layered insulator for use with a laser is disclosed which provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation. 4 figs.

Alger, T.W.

1994-09-06T23:59:59.000Z

316

Multiple density layered insulator  

DOE Patents [OSTI]

A multiple density layered insulator for use with a laser is disclosed wh provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation.

Alger, Terry W. (Tracy, CA)

1994-01-01T23:59:59.000Z

317

A MOVING-BOUNDARY PROBLEM FOR CONCRETE CARBONATION: GLOBAL EXISTENCE AND UNIQUENESS OF  

E-Print Network [OSTI]

in a porous solid ­ concrete ­ which incorporates slow diffusive transport, interfacial exchange between wet of gaseous CO2 from the atmosphere penetrate the concrete via the unsaturated porous matrix. After enteringA MOVING-BOUNDARY PROBLEM FOR CONCRETE CARBONATION: GLOBAL EXISTENCE AND UNIQUENESS OF WEAK

Eindhoven, Technische Universiteit

318

Multiple layer insulation cover  

DOE Patents [OSTI]

A multiple layer insulation cover for preventing heat loss in, for example, a greenhouse, is disclosed. The cover is comprised of spaced layers of thin foil covered fabric separated from each other by air spaces. The spacing is accomplished by the inflation of spaced air bladders which are integrally formed in the cover and to which the layers of the cover are secured. The bladders are inflated after the cover has been deployed in its intended use to separate the layers of the foil material. The sizes of the material layers are selected to compensate for sagging across the width of the cover so that the desired spacing is uniformly maintained when the cover has been deployed. The bladders are deflated as the cover is stored thereby expediting the storage process and reducing the amount of storage space required.

Farrell, James J. (Livingston Manor, NY); Donohoe, Anthony J. (Ovid, NY)

1981-11-03T23:59:59.000Z

319

Lagrangian Variational Framework for Boundary Value Problems  

E-Print Network [OSTI]

A boundary value problem is commonly associated with constraints imposed on a system at its boundary. We advance here an alternative point of view treating the system as interacting "boundary" and "interior" subsystems. This view is implemented through a Lagrangian framework that allows to account for (i) a variety of forces including dissipative acting at the boundary; (ii) a multitude of features of interactions between the boundary and the interior fields when the boundary fields may differ from the boundary limit of the interior fields; (iii) detailed pictures of the energy distribution and its flow; (iv) linear and nonlinear effects. We provide a number of elucidating examples of the structured boundary and its interactions with the system interior. We also show that the proposed approach covers the well known boundary value problems.

Alexander Figotin; Guillermo Reyes

2014-07-29T23:59:59.000Z

320

Strategic Environmental Research and Development Program: Atmospheric Remote Sensing and Assessment Program -- Final Report. Part 1: The lower atmosphere  

SciTech Connect (OSTI)

This report documents work done between FY91 and FY95 for the lower atmospheric portion of the joint Department of Defense (DoD) and Department of Energy (DOE) Atmospheric Remote Sensing and Assessment Program (ARSAP) within the Strategic Environmental Research and Development Program (SERDP). The work focused on (1) developing new measurement capabilities and (2) measuring atmospheric heating in a well-defined layer and then relating it to cloud properties an water vapor content. Seven new instruments were develop3ed for use with Unmanned Aerospace Vehicles (UAVs) as the host platform for flux, radiance, cloud, and water vapor measurements. Four major field campaigns were undertaken to use these new as well as existing instruments to make critically needed atmospheric measurements. Scientific results include the profiling of clear sky fluxes from near surface to 14 km and the strong indication of cloudy atmosphere absorption of solar radiation considerably greater than predicted by extant models.

Tooman, T.P. [ed.] [Sandia National Labs., Livermore, CA (United States). Exploratory Systems Technology Dept.

1997-01-01T23:59:59.000Z

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


321

Energy transport, overshoot, and mixing in the atmospheres of M-type main- and pre-main-sequence objects  

E-Print Network [OSTI]

We constructed hydrodynamical model atmospheres for mid M-type main-, as well as pre-main-sequence (PMS) objects. Despite the complex chemistry encountered in these cool atmospheres a reasonably accurate representation of the radiative transfer is possible, even in the context of time-dependent and three-dimensional models. The models provide detailed information about the morphology of M-type granulation and statistical properties of the convective surface flows. In particular, we determined the efficiency of the convective energy transport, and the efficiency of mixing by convective overshoot. The convective transport efficiency was expressed in terms of an equivalent mixing-length parameter alpha in the formulation of mixing-length theory (MLT) given by Mihalas (1978). Alpha amounts to values around 2 for matching the entropy of the deep, adiabatically stratified regions of the convective envelope, and lies between 2.5 and 3.0 for matching the thermal structure of the deep photosphere. For current spectral analysis of PMS objects this implies that MLT models based on alpha=2.0 overestimate the effective temperature by 100 K and surface gravities by 0.25 dex. The average thermal structure of the formally convectively stable layers is little affected by convective overshoot and wave heating, i.e., stays close to radiative equilibrium conditions. Our models suggest that the rate of mixing by convective overshoot declines exponentially with geometrical distance to the Schwarzschild stability boundary. It increases at given effective temperature with decreasing gravitational acceleration.

H. -G. Ludwig; F. Allard; P. H. Hauschildt

2006-08-12T23:59:59.000Z

322

TRANSONIC HYDRODYNAMIC ESCAPE OF HYDROGEN FROM EXTRASOLAR PLANETARY ATMOSPHERES  

E-Print Network [OSTI]

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

De Sterck, Hans

323

Thermal convection in a spherical shell with melting/freezing at either or both of its boundaries  

E-Print Network [OSTI]

In a number of geophysical or planetological settings (Earth's inner core, a silicate mantle crystallizing from a magma ocean, or an ice shell surrounding a deep water ocean) a convecting crystalline layer is in contact with a layer of its melt. Allowing for melting/freezing at one or both of the boundaries of the solid layer is likely to affect the pattern of convection in the layer. We study here the onset of thermal convection in a viscous spherical shell with dynamically induced melting/freezing at either or both of its boundaries. It is shown that the behavior of each interface depends on the value of a dimensional number P, which is the ratio of a melting/freezing timescale over a viscous relaxation timescale. A small value of P corresponds to permeable boundary conditions, while a large value of P corresponds to impermeable boundary conditions. The linear stability analysis predicts a significant effect of semi-permeable boundaries when the number P characterizing either of the boundary is small enough...

Deguen, Renaud

2013-01-01T23:59:59.000Z

324

Irradiation Assisted Grain Boundary Segregation in Steels  

SciTech Connect (OSTI)

The understanding of radiation-induced grain boundary segregation (RIS) has considerably improved over the past decade. New models have been introduced and much effort has been devoted to obtaining comprehensive information on segregation from the literature. Analytical techniques have also improved so that chemical analysis of layers 1 nm thick is almost routine. This invited paper will review the major methods used currently for RIS prediction: namely, Rate Theory, Inverse Kirkendall, and Solute Drag approaches. A summary is made of the available data on phosphorus RIS in reactor pressure vessel (RPV) steels. This will be discussed in the light of the predictions of the various models in an effort to show which models are the most reliable and easy to use for forecasting P segregation behaviour in steels. A consequence of RIS in RPV steels is a radiation induced shift in the ductile to brittle transition temperature (DBTT). It will be shown how it is possible to relate radiation-induced P segregation levels to DBTT shift. Examples of this exercise will be given for RPV steels and for ferritic steels being considered for first wall fusion applications. Cr RIS in high alloy stainless steels and associated irradiation-assisted stress corrosion cracking (IASCC) will be briefly discussed. (authors)

Lu, Zheng; Faulkner, Roy G. [IPTME, Loughborough University, Loughborough, Leics (United Kingdom)

2008-07-01T23:59:59.000Z

325

Alternative barrier layers for surface covers in dry climates  

SciTech Connect (OSTI)

Surface covers are one of the most widespread remediation and waste management options in all climates. Barrier layers to limit percolation through cover systems are principal features of engineered, multi-component cover designs. Conventional barrier layer components developed for humid climates have limitations in dry climates. One alternative barrier layer is a capillary barrier, which consists of a fine-over-coarse soil arrangement. The capacity of capillary barrier to laterally divert downward moving water is the key to their success. Another alternative is a dry barrier, in which atmospheric air is circulated through a coarse layer within the cover to remove water vapor. Incorporating a coarse layer which stores water for subsequent removal by air flow reduces the requirements for the air flow velocity and increases the applicability of the dry barrier.

Stormont, J.C.

1994-09-01T23:59:59.000Z

326

Structured luminescence conversion layer  

DOE Patents [OSTI]

An apparatus device such as a light source is disclosed which has an OLED device and a structured luminescence conversion layer deposited on the substrate or transparent electrode of said OLED device and on the exterior of said OLED device. The structured luminescence conversion layer contains regions such as color-changing and non-color-changing regions with particular shapes arranged in a particular pattern.

Berben, Dirk; Antoniadis, Homer; Jermann, Frank; Krummacher, Benjamin Claus; Von Malm, Norwin; Zachau, Martin

2012-12-11T23:59:59.000Z

327

Layered Spinach Salad Ingredients  

E-Print Network [OSTI]

cucumbers 2 tomatoes 1/2 cup low-fat mayonnaise 1/2 cup parmesan cheese, grated 1/4 cup milk 1 1/2 teaspoons size pieces, layer on bottom of a large bowl. 2. Rinse mushrooms off under cool water and use a soft half. Layer on top of vegetables. 6. To make salad dressing, add mayonnaise, cheese, milk, dill weed

Liskiewicz, Maciej

328

Beyond the no-slip boundary condition  

E-Print Network [OSTI]

This paper offers a simple macroscopic approach to the question of the slip boundary condition to be imposed upon the tangential component of the fluid velocity at a solid boundary. Plausible reasons are advanced for ...

Brenner, Howard

329

The Atmospheric Response to Realistic Reduced Summer Arctic Sea Ice Anomalies  

E-Print Network [OSTI]

for the continued ice melt [Polyakov et al., 2005], and recent work shows that heat from the Atlantic layer can91 The Atmospheric Response to Realistic Reduced Summer Arctic Sea Ice Anomalies Uma S. Bhatt,1 and Robert A. Tomas3 The impact of reduced Arctic summer sea ice on the atmosphere is investigated by forcing

Bhatt, Uma

330

SLE($?,?$)and Boundary Coulomb Gas  

E-Print Network [OSTI]

We consider the coulomb gas model on the upper half plane with different boundary conditions, namely Drichlet, Neuman and mixed. We related this model to SLE($\\kappa,\\rho$) theories. We derive a set of conditions connecting the total charge of the coulomb gas, the boundary charges, the parameters $\\kappa$ and $\\rho$. Also we study a free fermion theory in presence of a boundary and show with the same methods that it would lead to logarithmic boundary changing operators.

S. Moghimi-Araghi; M. A. Rajabpour; S. Rouhani

2005-08-07T23:59:59.000Z

331

Sandia National Laboratories: atomic layer deposition  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1development Sandia, NREL Release Wavearc-fault circuitatomic layer deposition

332

Layered electrode for electrochemical cells  

DOE Patents [OSTI]

There is provided an electrode structure comprising a current collector sheet and first and second layers of electrode material. Together, the layers improve catalyst utilization and water management.

Swathirajan, Swathy (West Bloomfield, MI); Mikhail, Youssef M. (Sterling Heights, MI)

2001-01-01T23:59:59.000Z

333

Dynamics of Atmospheres  

E-Print Network [OSTI]

transfer ­ Solar heating of surface, and atmosphere via dust absorption ­ Infrared CO2 band cooling (especially around 667 cm-1) ­ nonLTE near-infrared heating of CO2 and nonLTE cooling effects above ~60-80 km. Baroclinic waves, scales, heat and momentum transport, seasonal occurrence. Qualitative treatment

Read, Peter L.

334

Dynamics of Planetary Atmospheres  

E-Print Network [OSTI]

pressure (bars) N2 82%; Ar 12%; CH4 6%CO2 96.5%; N2 3.5%Atmospheric composition 26177Orbital inclination (1992) orbiter ­ Winds from cloud-tracking and probe drifts ­ IR temperatures, solar-fixed tides, polar-Huygens mission (from 2005) ­ Doppler wind descent profile ­ IR temperature and composition maps ­ Visible, IR

Read, Peter L.

335

Where do fossil fuel carbon dioxide emissions from California go? An analysis based on radiocarbon observations and an atmospheric transport model  

SciTech Connect (OSTI)

Characterizing flow patterns and mixing of fossil fuel-derived CO{sub 2} is important for effectively using atmospheric measurements to constrain emissions inventories. Here we used measurements and a model of atmospheric radiocarbon ({sup 14}C) to investigate the distribution and fluxes of atmospheric fossil fuel CO{sub 2} across the state of California. We sampled {sup 14}C in annual C{sub 3} grasses at 128 sites and used these measurements to test a regional model that simulated anthropogenic and ecosystem CO{sub 2} fluxes, transport in the atmosphere, and the resulting {sup 14}C of annual grasses ({Delta}{sub g}). Average measured {Delta}{sub g} in Los Angeles, San Francisco, the Central Valley, and the North Coast were 27.7 {+-} 20.0, 44.0 {+-} 10.9, 48.7 {+-} 1.9, and 59.9 {+-} 2.5{per_thousand}, respectively, during the 2004-2005 growing season. Model predictions reproduced regional patterns reasonably well, with estimates of 27.6 {+-} 2.4, 39.4 {+-} 3.9, 46.8 {+-} 3.0, and 59.3 {+-} 0.2{per_thousand} for these same regions and corresponding to fossil fuel CO{sub 2} mixing ratios (Cf) of 13.7, 6.1, 4.8, and 0.3 ppm. {Delta}{sub g} spatial heterogeneity in Los Angeles and San Francisco was higher in the measurements than in the predictions, probably from insufficient spatial resolution in the fossil fuel inventories (e.g., freeways are not explicitly included) and transport (e.g., within valleys). We used the model to predict monthly and annual transport patterns of fossil fuel-derived CO{sub 2} within and out of California. Fossil fuel CO{sub 2} emitted in Los Angeles and San Francisco was predicted to move into the Central Valley, raising Cf above that expected from local emissions alone. Annually, about 21, 39, 35, and 5% of fossil fuel emissions leave the California airspace to the north, east, south, and west, respectively, with large seasonal variations in the proportions. Positive correlations between westward fluxes and Santa Ana wind conditions were observed. The southward fluxes over the Pacific Ocean were maintained in a relatively coherent flow within the marine boundary layer, while the eastward fluxes were more vertically dispersed. Our results indicate that state and continental scale atmospheric inversions need to consider areas where concentration measurements are sparse (e.g., over the ocean to the south and west of California), transport within and across the marine boundary layer, and terrestrial boundary layer dynamics. Measurements of {Delta}{sub g} can be very useful in constraining these estimates.

Riley, W.J.; Hsueh, D.Y.; Randerson, J.T.; Fischer, M.L.; Hatch, J.G.; Pataki, D.E.; Wang, W.; Goulden, M.L.

2008-05-01T23:59:59.000Z

336

Universality of the Future Chronological Boundary  

E-Print Network [OSTI]

The purpose of this note is to establish, in a categorical manner, the universality of the Geroch-Kronheimer-Penrose causal boundary when considering the types of causal structures that may profitably be put on any sort of boundary for a spacetime. Actually, this can only be done for the future causal boundary (or the past causal boundary) separately; furthermore, only the chronology relation, not the causality relation, is considered, and the GKP topology is eschewed. The final result is that there is a unique map, with the proper causal properties, from the future causal boundary of a spacetime onto any ``reasonable" boundary which supports some sort of chronological structure and which purports to consist of a future completion of the spacetime. Furthermore, the future causal boundary construction is categorically unique in this regard.

Steven G. Harris

1997-04-04T23:59:59.000Z

337

Geometric Boundary Data for the Gravitational Field  

E-Print Network [OSTI]

An outstanding issue in the treatment of boundaries in general relativity is the lack of a local geometric interpretation of the necessary boundary data. For the Cauchy problem, the initial data is supplied by the 3-metric and extrinsic curvature of the initial Cauchy hypersurface.. This Cauchy data determines a solution to Einstein's equations which is unique up to a diffeomorphism. Here, we show how three pieces of boundary data, which are associated locally with the geometry of the boundary, likewise determine a solution of the initial-boundary value problem which is unique up to a diffeomorphism. One piece of this data, constructed from the extrinsic curvature of the boundary, determines the dynamical evolution of the boundary. The other two pieces constitute a conformal class of rank-2, positive definite metrics, which represent the two gravitational degrees of freedom.

H-O. Kreiss; J. Winicour

2014-02-25T23:59:59.000Z

338

Impact of boundaries on velocity profiles in bubble rafts  

E-Print Network [OSTI]

Under conditions of sufficiently slow flow, foams, colloids, granular matter, and various pastes have been observed to exhibit shear localization, i.e. regions of flow coexisting with regions of solid-like behavior. The details of such shear localization can vary depending on the system being studied. A number of the systems of interest are confined so as to be quasi-two dimensional, and an important issue in these systems is the role of the confining boundaries. For foams, three basic systems have been studied with very different boundary conditions: Hele-Shaw cells (bubbles confined between two solid plates); bubble rafts (a single layer of bubbles freely floating on a surface of water); and confined bubble rafts (bubbles confined between the surface of water below and a glass plate on top). Often, it is assumed that the impact of the boundaries is not significant in the ``quasi-static limit'', i.e. when externally imposed rates of strain are sufficiently smaller than internal kinematic relaxation times. In this paper, we directly test this assumption for rates of strain ranging from $10^{-3}$ to $10^{-2} {\\rm s^{-1}}$. This corresponds to the quoted quasi-static limit in a number of previous experiments. It is found that the top plate dramatically alters both the velocity profile and the distribution of nonlinear rearrangements, even at these slow rates of strain.

Yuhong Wang; Kapilanjan Krishan; Michael Dennin

2006-01-31T23:59:59.000Z

339

Layered semiconductor neutron detectors  

DOE Patents [OSTI]

Room temperature operating solid state hand held neutron detectors integrate one or more relatively thin layers of a high neutron interaction cross-section element or materials with semiconductor detectors. The high neutron interaction cross-section element (e.g., Gd, B or Li) or materials comprising at least one high neutron interaction cross-section element can be in the form of unstructured layers or micro- or nano-structured arrays. Such architecture provides high efficiency neutron detector devices by capturing substantially more carriers produced from high energy .alpha.-particles or .gamma.-photons generated by neutron interaction.

Mao, Samuel S; Perry, Dale L

2013-12-10T23:59:59.000Z

340

Differential atmospheric tritium sampler  

DOE Patents [OSTI]

An atmospheric tritium sampler is provided which uses a carrier gas comprised of hydrogen gas and a diluting gas, mixed in a nonexplosive concentration. Sample air and carrier gas are drawn into and mixed in a manifold. A regulator meters the carrier gas flow to the manifold. The air sample/carrier gas mixture is pulled through a first moisture trap which adsorbs water from the air sample. The moisture then passes through a combustion chamber where hydrogen gas in the form of H/sub 2/ or HT is combusted into water. The manufactured water is transported by the air stream to a second moisture trap where it is adsorbed. The air is then discharged back into the atmosphere by means of a pump.

Griesbach, O.A.; Stencel, J.R.

1987-10-02T23:59:59.000Z

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


341

Differential atmospheric tritium sampler  

DOE Patents [OSTI]

An atmospheric tritium sampler is provided which uses a carrier gas comprised of hydrogen gas and a diluting gas, mixed in a nonexplosive concentration. Sample air and carrier gas are drawn into and mixed in a manifold. A regulator meters the carrier gas flow to the manifold. The air sample/carrier gas mixture is pulled through a first moisture trap which adsorbs water from the air sample. The mixture then passes through a combustion chamber where hydrogen gas in the form of H.sub.2 or HT is combusted into water. The manufactured water is transported by the air stream to a second moisture trap where it is adsorbed. The air is then discharged back into the atmosphere by means of a pump.

Griesbach, Otto A. (Langhorne, PA); Stencel, Joseph R. (Skillman, NJ)

1990-01-01T23:59:59.000Z

342

The changing atmosphere  

SciTech Connect (OSTI)

The chemistry of the atmosphere is changing, in large measure because of gases emitted by such human activities as farming, manufacturing, and the combustion of fossil fuels. The deleterious effects are increasingly evident; they may well become worse in the years ahead. This paper discusses the pollutants and the environmental perturbations with which they are associated. The authors believe the solution to the earth's environmental problems lies in a truly global effort.

Graedel, T.E.; Crutzen, P.J.

1989-09-01T23:59:59.000Z

343

Control System For Cryogenic THD Layering At The National Ignition Facility  

SciTech Connect (OSTI)

The National Ignition Facility (NIF) is the world largest and most energetic laser system for Inertial Confinement Fusion (ICF). In 2010, NIF began ignition experiments using cryogenically cooled targets containing layers of the tritium-hydrogen-deuterium (THD) fuel. The 75 {micro}m thick layer is formed inside of the 2 mm target capsule at temperatures of approximately 18 K. The ICF target designs require sub-micron smoothness of the THD ice layers. Formation of such layers is still an active research area, requiring a flexible control system capable of executing the evolving layering protocols. This task is performed by the Cryogenic Target Subsystem (CTS) of the NIF Integrated Computer Control System (ICCS). The CTS provides cryogenic temperature control with the 1 mK resolution required for beta-layering and for the thermal gradient fill of the capsule. The CTS also includes a 3-axis x-ray radiography engine for phase contrast imaging of the ice layers inside of the plastic and beryllium capsules. In addition to automatic control engines, CTS is integrated with the Matlab interactive programming environment to allow flexibility in experimental layering protocols. The CTS Layering Matlab Toolbox provides the tools for layer image analysis, system characterization and cryogenic control. The CTS Layering Report tool generates qualification metrics of the layers, such as concentricity of the layer and roughness of the growth boundary grooves. The CTS activities are automatically coordinated with other NIF controls in the carefully orchestrated NIF Shot Sequence.

Fedorov, M; Blubaugh, J; Edwards, O; Mauvais, M; Sanchez, R; Wilson, B

2011-03-18T23:59:59.000Z

344

Environmental Chemistry II (Atmospheric Chemistry)  

E-Print Network [OSTI]

Seinfeld, J. H. and Pandis, S. N. Atmospheric Chemistry and Physics: From Air Pollution to Climate ChangeSYLLABUS FOR Environmental Chemistry II (Atmospheric Chemistry) FCH 511 Fall 2013 Theodore S

Dibble, Theodore

345

Shaping Environmental Justice: Applying Science, Technology, and Society Boundary Work  

E-Print Network [OSTI]

Applying Science, Technology and Society Boundary Work Chih-the STS (Science, Technology and Society) study as boundary-

Huang, Chih-Tung

2012-01-01T23:59:59.000Z

346

Determination of HEat Capacity of Yucca Mountain Strtigraphic Layers  

SciTech Connect (OSTI)

The heat generated from the radioactive waste to be placed in the proposed geologic repository at Yucca Mountain, Nevada, will affect the thermal-hydrology of the Yucca Mountain stratigraphic layers. In order to assess the effect of the movement of repository heat into the fractured rocks accurate determination of thermodynamic and hydraulic properties is important. Heat capacity is one of the properties that are required to evaluate energy storage in the fractured rock. Rock-grain heat capacity, the subject of this study, is the heat capacity of the solid part of the rock. Yucca Mountain consists of alternating lithostratigraphic units of welded and non-welded ash-flow tuff, mainly rhyolitic in composition and displaying varying degrees of vitrification and alteration. A number of methods exist that can be used to evaluate heat capacity of the stratigraphic layers that consist of different compositions. In this study, the mineral summation method has been used to quantify the heat capacity of the stratigraphic layers based on Kopp's rule. The mineral summation method is an addition of the weighted heat capacity of each mineral found in a specific layer. For this study the weighting was done based on the mass percentage of each mineral in the layer. The method utilized a mineralogic map of the rocks at the Yucca Mountain repository site. The Calico Hills formation and adjacent bedded tuff layers display a bimodal mineral distribution of vitric and zeolitic zones with differing mineralogies. Based on this bimodal distribution in zeolite abundance, the boundary between the vitric and zeolitic zones was selected to be 15% zeolitic abundance. Thus, based on the zeolite abundance, subdivisions have been introduced to these layers into ''vitric'' and ''zeolitic'' zones. Heat capacity values have been calculated for these layers both as ''layer average'' and ''zone average''. The heat capacity determination method presented in this report did not account for spatial variability in the horizontal direction within each layer.

T. Hadgu; C. Lum; J.E. Bean

2006-06-20T23:59:59.000Z

347

Pluto's Atmosphere Does Not Collapse  

E-Print Network [OSTI]

Combining stellar occultation observations probing Pluto's atmosphere from 1988 to 2013 and models of energy balance between Pluto's surface and atmosphere, we conclude that Pluto's atmosphere does not collapse at any point in its 248-year orbit. The occultation results show an increasing atmospheric pressure with time in the current epoch, a trend present only in models with a high thermal inertia and a permanent N2 ice cap at Pluto's north rotational pole.

Olkin, C B; Borncamp, D; Pickles, A; Sicardy, B; Assafin, M; Bianco, F B; Buie, M W; de Oliveira, A Dias; Gillon, M; French, R G; Gomes, A Ramos; Jehin, E; Morales, N; Opitom, C; Ortiz, J L; Maury, A; Norbury, M; Ribas, F B; Smith, R; Wasserman, L H; Young, E F; Zacharias, M; Zacharias, N

2013-01-01T23:59:59.000Z

348

Gradient zone-boundary control in salt-gradient solar ponds  

DOE Patents [OSTI]

A method and apparatus for suppressing zone boundary migration in a salt gradient solar pond includes extending perforated membranes across the pond at the boundaries, between the convective and non-convective zones, the perforations being small enough in size to prevent individual turbulence disturbances from penetrating the hole, but being large enough to allow easy molecular diffusion of salt thereby preventing the formation of convective zones in the gradient layer. The total area of the perforations is a sizeable fraction of the membrane area to allow sufficient salt diffusion while preventing turbulent entrainment into the gradient zone.

Hull, J.R.

1982-09-29T23:59:59.000Z

349

Plasma Boundary Colloquium.key  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006Photovoltaic Theory and ModelingPinkand ResultsExcitement at the

350

pac 2003 boundary3.ppt  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched5 Industrial Carbon CaptureFY08 Joint JOULE J.nbarbeeLargeNHMFL-PFF at51( ( ( ( (5-yr

351

Observation of thermally etched grain boundaries with the FIB/TEM technique  

SciTech Connect (OSTI)

Thermal etching is a method which is able to reveal and characterize grain boundaries, twins or dislocation structures and determine parameters such as grain boundary energies, surface diffusivities or study phase transformations in steels, intermetallics or ceramic materials. This method relies on the preferential transfer of matter away from grain boundaries on a polished sample during heating at high temperatures in an inert/vacuum atmosphere. The evaporation/diffusion of atoms at high temperatures results in the formation of grooves at the intersections of the planes of grain/twin boundaries with the polished surface. This work describes how the combined use of Focussed Ion Beam and Transmission Electron Microscopy can be used to characterize not only the grooves and their profile with the surface, but also the grain boundary line below the groove, this method being complementary to the commonly used scanning probe techniques. - Highlights: • Thermally etched low-carbon steel samples have been characterized by FIB/TEM • Grain boundary (GB) lines below the groove have been characterized in this way • Absence of ghost traces and large ? angle suggests that GB are not stationary but mobile • Observations correlate well with previous works and Mullins' investigations [22].

Palizdar, Y., E-mail: y.palizdar@merc.ac.ir [Nanotechnology and advanced materials department, Materials and energy research centre (MERC), Karaj (Iran, Islamic Republic of); San Martin, D. [MATERALIA group, Department of Physical Metallurgy, (CENIM-CSIC), Centro Nacional de Investigaciones Metalúrgicas Av. Gregorio del Amo 8, 28040 Madrid (Spain); Ward, M.; Cochrane, R.C.; Brydson, R.; Scott, A.J. [Institute for Materials Research, SPEME, University of Leeds, Leeds LS2 9JT (United Kingdom)

2013-10-15T23:59:59.000Z

352

Atmospheric model intercomparison project: Monsoon simulations  

SciTech Connect (OSTI)

The simulation of monsoons, in particular the Indian summer monsoon, has proven to be a critical test of a general circulation model`s ability to simulate tropical climate and variability. The Monsoon Numerical Experimentation Group has begun to address questions regarding the predictability of monsoon extremes, in particular conditions associated with El Nino and La Nina conditions that tend to be associated with drought and flood conditions over the Indian subcontinent, through a series of seasonal integrations using analyzed initial conditions from successive days in 1987 and 1988. In this paper the authors present an analysis of simulations associated with the Atmospheric Model Intercomparison Project (AMIP), a coordinated effort to simulate the 1979--1988 decade using standardized boundary conditions with approximately 30 atmospheric general circulation models. The 13 models analyzed to date are listed. Using monthly mean data from these simulations they have calculated indices of precipitation and wind shear in an effort to access the performance of the models over the course of the AMIP decade.

Sperber, K.R. [Lawrence Livermore National Lab., CA (United States). Program for Climate Model Diagnosis and Intercomparison; Palmer, T.N. [European Centre for Medium-Range Weather Forecasts, Reading (United Kingdom)

1994-06-01T23:59:59.000Z

353

On the effects of atmospheric refraction on radar ground patterns  

E-Print Network [OSTI]

of superrefraction. A radial pattern of AP echoes occurred in a number of cases when there was a strong gradient of N in an elevated refractive layer, but this pattern was not nearly as common as others. Investigations [10, 13, 14, 15, 16] of the atmosphere... when the antenna elevation angle is less than 2 deg and when there is an elevated refracting layer between 1500 ft and 3000 ft above the radar in which the gradient of refractivity is greater than 48N/1000 ft. ACKNONLEDGMENT The author wishes...

Cobb, Lalovee Glendale

1963-01-01T23:59:59.000Z

354

Moment problems and boundaries of number triangles  

E-Print Network [OSTI]

The boundary problem for graphs like Pascal's but with general multiplicities of edges is related to a `backward' problem of moments of the Hausdorff type.

Gnedin, Alexander

2008-01-01T23:59:59.000Z

355

Performance Boundaries in Nb3Sn Superconductors  

E-Print Network [OSTI]

Boundaries in Nb 3 Sn Superconductors – Berkeley, CABoundaries in Nb 3 Sn Superconductors – Berkeley, CABoundaries in Nb 3 Sn Superconductors Arno Godeke Berkeley,

Godeke, Arno

2006-01-01T23:59:59.000Z

356

Casimir pistons with hybrid boundary conditions  

E-Print Network [OSTI]

The Casimir effect giving rise to an attractive or repulsive force between the configuration boundaries that confine the massless scalar field is reexamined for one to three-dimensional pistons in this paper. Especially, we consider Casimir pistons with hybrid boundary conditions, where the boundary condition on the piston is Neumann and those on other surfaces are Dirichlet. We show that the Casimir force on the piston is always repulsive, in contrast with the same problem where the boundary conditions are Dirichlet on all surfaces.

Xiang-hua Zhai; Xin-zhou Li

2007-04-30T23:59:59.000Z

357

Atmospheric Aerosol Systems | EMSL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation InInformationCenterResearch HighlightsTools PrintableCARIBU ProposalBeamAtmospheric

358

Atmospheric Radiation Measurement Program  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4August 1999 ARM

359

Atmospheric Radiation Measurement Program  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4August 1999

360

Atmospheric Radiation Measurement Program  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4August 1999July

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


361

Atmospheric Radiation Measurement Program  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4August

362

Atmospheric Radiation Measurement Program  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4August3 ARM 2003

363

Atmospheric Particulates | EMSL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone byDear Friend,Arthur J. Nozik -GrownAn overheadAtmospheric

364

Engineering electroresponsive layer-by-layer thin films  

E-Print Network [OSTI]

Electroresponsive layer-by-layer (LbL) polymer films and polymer nanocomposite films were investigated as model systems for electrically triggered drug delivery applications and "mechanomutable" surface coating applications. ...

Schmidt, Daniel J., Ph. D. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

365

Ion transport and structure of layer-by-layer assemblies  

E-Print Network [OSTI]

Layer-by-layer (LbL) films of various architectures were examined as potential solid state electrolytes for electrochemical systems (e.g. batteries and fuel cells). The relationship between materials properties and ion ...

Lutkenhaus, Jodie Lee

2007-01-01T23:59:59.000Z

366

Layer-by-layer assembly in confined geometries  

E-Print Network [OSTI]

The fundamental nature of layer-by-layer (LbL) assembly in confined geometries was investigated for a number of different chemical systems. The first part of this thesis concerns the modification of microfluidic and ...

DeRocher, Jonathan P

2011-01-01T23:59:59.000Z

367

Direct Simulation of Shock Layer Plasmas  

SciTech Connect (OSTI)

Approximate models of the electric field used with the DSMC method all impose quasi-neutrality everywhere in the shock layer plasma. The shortcomings of these models are examined in this study by simulating a weak shock layer plasma with a coupled DSMC-Particle-In-Cell (PIC) method. The stagnation streamline of an axisymmetric shock layer is simulated for entry velocities in air that correspond to both lunar and Mars return trajectories. The atmospheric densities, particle diameters and chemical reaction rates are varied from the actual values to make the computations tractable while retaining the mean free path of air at 85 km altitude. In contrast to DSMC flow field predictions, regions of non-neutrality are predicted by the DSMC-PIC method, and the electrons are predicted to be isothermal. Perhaps the most important result of this study is that the DSMC-PIC results at both reentry energies yield a 14% increase in heat flux to the vehicle surface relative to the DSMC results. Rather unintuitively, this is mostly due to an increase in ion flux to the surface, rather than the potential energy gained by each ion as it traverses the plasma sheath. In this study, an approximate electric field model is presented, with the goal of accounting for this heat flux augmentation without the need for a computationally expensive DSMC-PIC calculation of the entire flow-field. Convective heat flux results obtained with new electric field model are compared to results from the rigorous DSMC-PIC calculations.

Farbar, E. D.; Boyd, I. D. [Dept. of Aerospace Engineering, University of Michigan, 1320 Beal Ave., Ann Arbor MI, 48109 (United States)

2011-05-20T23:59:59.000Z

368

Spatially Resolved Mapping of Electrical Conductivity around Individual Domain (Grain) Boundaries in Graphene  

SciTech Connect (OSTI)

Graphene films can now be produced on the scale of up to meters. However, all large-scale graphene films contain topological defects that can significantly affect the characteristic transport behaviors of graphene. Here, we spatially map the structures and electronic transport near specific domain and grain boundaries in graphene, and evaluate effects of different types of defect on the electronic conductivity in epitaxial graphene grown on SiC and CVD graphene on Cu subsequently transferred to a SiO2 substrate. We use a combined approach with a multi-probe scanning tunneling potentiometry to investigate both structures and transport at individual grain boundaries and domain boundaries that are defined by coalesced grains, surface steps, and changes in layer thickness. It is found that the substrate step on SiC presents a significant potential barrier for electron transport of epitaxial graphene due to the reduced charge transport from the substrate at the step edges, monolayer-bilayer boundaries exhibit a high resistivity that can change depending on directions of the current across the boundary, and the resistivity of grain boundaries changes with the transition width of the disordered region between two adjacent grains in graphene. The detailed understanding of graphene defects will provide the feedback for controlled engineering of defects in large-scale graphene films.

Li, An-Ping [ORNL; Clark, Kendal W [ORNL; Zhang, Xiaoguang [ORNL; Vlassiouk, Ivan V [ORNL; He, Guowei [Carnegie Mellon University (CMU); Feenstra, Randall [Carnegie Mellon University (CMU)

2013-01-01T23:59:59.000Z

369

Growth of Large-Area Single- and Bi-Layer Graphene by Controlled Carbon Precipitation on Polycrystalline Ni Surfaces  

E-Print Network [OSTI]

We report graphene films composed mostly of one or two layers of graphene grown by controlled carbon precipitation on the surface of polycrystalline Ni thin films during atmospheric chemical vapor deposition (CVD). Controlling ...

Reina, Alfonso

2009-01-01T23:59:59.000Z

370

Ocean Barrier Layers’ Effect on Tropical Cyclone Intensification  

SciTech Connect (OSTI)

Improving a tropical cyclone's forecast and mitigating its destructive potential requires knowledge of various environmental factors that influence the cyclone's path and intensity. Herein, using a combination of observations and model simulations, we systematically demonstrate that tropical cyclone intensification is significantly affected by salinity-induced barrier layers, which are 'quasi-permanent' features in the upper tropical oceans. When tropical cyclones pass over regions with barrier layers, the increased stratification and stability within the layer reduce storm-induced vertical mixing and sea surface temperature cooling. This causes an increase in enthalpy flux from the ocean to the atmosphere and, consequently, an intensification of tropical cyclones. On average, the tropical cyclone intensification rate is nearly 50% higher over regions with barrier layers, compared to regions without. Our finding, which underscores the importance of observing not only the upper-ocean thermal structure but also the salinity structure in deep tropical barrier layer regions, may be a key to more skillful predictions of tropical cyclone intensities through improved ocean state estimates and simulations of barrier layer processes. As the hydrological cycle responds to global warming, any associated changes in the barrier layer distribution must be considered in projecting future tropical cyclone activity.

Balaguru, Karthik; Chang, P.; Saravanan, R.; Leung, Lai-Yung R.; Xu, Zhao; Li, M.; Hsieh, J.

2012-09-04T23:59:59.000Z

371

A mathematical model of corrosion of a conducting porous layer on a rotating disk electrode  

E-Print Network [OSTI]

. This approach, however, fails to account, for many of the complexities involved in actual corrosion such as pH effects upon passivation and reverse kinetics of oxygen reduction reaction. In a later study, Alkire and Siitari (21) characterized an ideal pitting.... Description of Porous Electrode B. Governing Equations? Solution Diffusion Layer C. Governing Equations? Porous Electrode Layer D. Butler-Volmer Kinetic Rate Equation E. Boundary Conditions F. Solution Technique 12 14 17 IV RESULTS AND DISCUSSION A...

Ryan, William Edward

1986-01-01T23:59:59.000Z

372

Prediction Error and Event Boundaries 1 Running Head: PREDICTION ERROR AND EVENT BOUNDARIES  

E-Print Network [OSTI]

Prediction Error and Event Boundaries 1 Running Head: PREDICTION ERROR AND EVENT BOUNDARIES A computational model of event segmentation from perceptual prediction. Jeremy R. Reynolds, Jeffrey M. Zacks, and Todd S. Braver Washington University Manuscript #12;Prediction Error and Event Boundaries 2 People tend

Zacks, Jeffrey M.

373

The Lithium Depletion Boundary as a Clock and Thermometer  

E-Print Network [OSTI]

We take a critical look at the lithium depletion boundary (LDB) technique that has recently been used to derive the ages of open clusters. We identify the sources of experimental and systematic error and show that the probable errors are larger by approximately a factor two than presently claimed in the literature. We then use the Pleiades LDB age and photometry in combination with evolutionary models to define empirical colour-T_eff relations that can be applied to younger clusters. We find that these relationships DO NOT produce model isochrones that match the younger cluster data. We propose that this is due either to systematic problems in the evolutionary models or an age (gravity) sensitivity in the colour-T_eff relation which is not present in published atmospheric models.

R. D. Jeffries; T. Naylor

2000-09-12T23:59:59.000Z

374

Green's functions for Neumann boundary conditions  

E-Print Network [OSTI]

Green's functions for Neumann boundary conditions have been considered in Math Physics and Electromagnetism textbooks, but special constraints and other properties required for Neumann boundary conditions have generally not been noticed or treated correctly. In this paper, we derive an appropriate Neumann Green's function with these constraints and properties incorporated.

Jerrold Franklin

2012-08-27T23:59:59.000Z

375

Cherokee Clitics: The Word Boundary Problem  

E-Print Network [OSTI]

The problem of identifying Cherokee clitics is complicated by the fact that the prosodic word, marked by the presence of a tonal boundary, may not match the morphological word. Clitics may or may not respect the the word boundary as marked by tone...

Haag, Marcia

1999-01-01T23:59:59.000Z

376

New boundary conditions for granular fluids  

E-Print Network [OSTI]

We present experimental evidence, which contradicts the the standard boundary conditions used in continuum theories of non-cohesive granular flows for the velocity normal to a boundary u.n=0, where n points into the fluid. We propose and experimentally verify a new boundary condition for u.n, based on the observation that the boundary cannot exert a tension force Fb on the fluid. The new boundary condition is u.n=0 if Fb.n>=0 else n.P.n=0, where P is the pressure tensor. This is the analog of cavitation in ordinary fluids, but due the lack of attractive forces and dissipation it occurs frequently in granular flows.

Mark D. Shattuck

2007-03-22T23:59:59.000Z

377

Atmospheric propagation of THz radiation.  

SciTech Connect (OSTI)

In this investigation, we conduct a literature study of the best experimental and theoretical data available for thin and thick atmospheres on THz radiation propagation from 0.1 to 10 THz. We determined that for thick atmospheres no data exists beyond 450 GHz. For thin atmospheres data exists from 0.35 to 1.2 THz. We were successful in using FASE code with the HITRAN database to simulate the THz transmission spectrum for Mauna Kea from 0.1 to 2 THz. Lastly, we successfully measured the THz transmission spectra of laboratory atmospheres at relative humidities of 18 and 27%. In general, we found that an increase in the water content of the atmosphere led to a decrease in the THz transmission. We identified two potential windows in an Albuquerque atmosphere for THz propagation which were the regions from 1.2 to 1.4 THz and 1.4 to 1.6 THz.

Wanke, Michael Clement; Mangan, Michael A.; Foltynowicz, Robert J.

2005-11-01T23:59:59.000Z

378

Boundary Behavior of the Ginzburg-Landau Order Parameter in the Surface Superconductivity Regime  

E-Print Network [OSTI]

We study the 2D Ginzburg-Landau theory for a type-II superconductor in an applied magnetic field varying between the second and third critical value. In this regime the order parameter minimizing the GL energy is concentrated along the boundary of the sample and is well approximated to leading order by a simplified 1D profile in the direction perpendicular to the boundary. Motivated by a conjecture of Xing-Bin Pan, we address the question of whether this approximation can hold uniformly in the boundary region. We prove that this is indeed the case as a corollary of a refined, second order energy expansion including contributions due to the curvature of the sample. Local variations of the GL order parameter are controlled by the second order term of this energy expansion, which allows us to prove the desired uniformity of the surface superconductivity layer.

M. Correggi; N. Rougerie

2015-01-27T23:59:59.000Z

379

12th AIAA/CEAS Aeroacoustics Conference, May 8---10, 2006, Cambridge, Massachusetts PML absorbing boundary condition for nonlinear  

E-Print Network [OSTI]

. R. China Perfectly Matched Layer (PML) absorbing boundary condition for the compressible non­ linear shedding from a viscous flow over a circular cylinder are presented. Satisfactory results demonstrated that the absorbing zone is theoretically reflectionless for multi­dimensional linear waves of any angle and frequency

Hu, Fang Q.

380

P8.13 CONTRAIL STUDIES AND FORECASTS IN THE SUBARCTIC ATMOSPHERE ABOVE FAIRBANKS, Martin Stuefer* and Gerd Wendler  

E-Print Network [OSTI]

, the radiative characteristics of contrails are similar to those of thin layers of naturally occurring cirrus are of interest for scientists investigating atmospheric radiation transfer processes, the chemical state of temperatures in the lower atmosphere by reducing the net radiation to the surface during the day and reducing

Stuefer, Martin

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


381

Metal deposition using seed layers  

DOE Patents [OSTI]

Methods of forming a conductive metal layers on substrates are disclosed which employ a seed layer to enhance bonding, especially to smooth, low-roughness or hydrophobic substrates. In one aspect of the invention, the seed layer can be formed by applying nanoparticles onto a surface of the substrate; and the metallization is achieved by electroplating an electrically conducting metal onto the seed layer, whereby the nanoparticles serve as nucleation sites for metal deposition. In another approach, the seed layer can be formed by a self-assembling linker material, such as a sulfur-containing silane material.

Feng, Hsein-Ping; Chen, Gang; Bo, Yu; Ren, Zhifeng; Chen, Shuo; Poudel, Bed

2013-11-12T23:59:59.000Z

382

Buried oxide layer in silicon  

DOE Patents [OSTI]

A process for forming Silicon-On-Insulator is described incorporating the steps of ion implantation of oxygen into a silicon substrate at elevated temperature, ion implanting oxygen at a temperature below 200.degree. C. at a lower dose to form an amorphous silicon layer, and annealing steps to form a mixture of defective single crystal silicon and polycrystalline silicon or polycrystalline silicon alone and then silicon oxide from the amorphous silicon layer to form a continuous silicon oxide layer below the surface of the silicon substrate to provide an isolated superficial layer of silicon. The invention overcomes the problem of buried isolated islands of silicon oxide forming a discontinuous buried oxide layer.

Sadana, Devendra Kumar (Pleasantville, NY); Holland, Orin Wayne (Lenoir, TN)

2001-01-01T23:59:59.000Z

383

Regional forecasting with global atmospheric models; Final report  

SciTech Connect (OSTI)

The purpose of the project was to conduct model simulations for past and future climate change with respect to the proposed Yucca Mtn. repository. The authors report on three main topics, one of which is boundary conditions for paleo-hindcast studies. These conditions are necessary for the conduction of three to four model simulations. The boundary conditions have been prepared for future runs. The second topic is (a) comparing the atmospheric general circulation model (GCM) with observations and other GCMs; and (b) development of a better precipitation data base for the Yucca Mtn. region for comparisons with models. These tasks have been completed. The third topic is preliminary assessments of future climate change. Energy balance model (EBM) simulations suggest that the greenhouse effect will likely dominate climate change at Yucca Mtn. for the next 10,000 years. The EBM study should improve rational choice of GCM CO{sub 2} scenarios for future climate change.

Crowley, T.J.; Smith, N.R. [Applied Research Corp., College Station, TX (United States)

1994-05-01T23:59:59.000Z

384

ATMOSPHERIC ELSEVIER AtmosphericResearch 44 (1997) 231-241  

E-Print Network [OSTI]

ATMOSPHERIC RESEARCH ELSEVIER AtmosphericResearch 44 (1997) 231-241 Error analysis of backscatter;accepted 14 February 1997 Abstract Ice sphere backscatter has been calculated using both Mie theory as a reasonable approximation for rv 1997 Elsevier Science B.V. 1. Introduction Cirrus clouds play

Reading, University of

385

ELSEVIER AtmosphericResearch 38 (1995) 207-235 ATMOSPHERIC  

E-Print Network [OSTI]

ELSEVIER AtmosphericResearch 38 (1995) 207-235 ATMOSPHERIC RESEARCH On the parameterization of ice and water substance mixing ratio fields were only strongly altered by turning off the ice phase of these schemes includes ice processes. But in mid- latitudes and also in tropics the ice phase is an important

Moelders, Nicole

386

A dominant role of oxygen additive on cold atmospheric-pressure He + O{sub 2} plasmas  

SciTech Connect (OSTI)

We present in this paper how oxygen additive impacts on the cold atmospheric-pressure helium plasmas by means of a one-dimensional fluid model. For the oxygen concentration [O{sub 2}]?>??0.1%, the influence of oxygen on the electron characteristics and the power dissipation becomes important, e.g., the electron density, the electron temperature in sheath, the electron-coupling power, and the sheath width decreasing by 1.6 to 16 folds with a two-log increase in [O{sub 2}] from 0.1% to 10%. Also the discharge mode evolves from the ? mode to the ? mode. The reactive oxygen species are found to peak in the narrow range of [O{sub 2}]?=?0.4%–0.9% in the plasmas, similar to their power-coupling values. This applies to their wall fluxes except for those of O* and O{sub 2}{sup ?}. These two species have very short lifetimes, thus only when generated in boundary layers within several micrometers next to the electrode can contribute to the fluxes. The dominant reactive oxygen species and the corresponding main reactions are schematically presented, and their relations are quantified for selected applications.

Yang, Aijun; Liu, Dingxin, E-mail: liudingxin@gmail.com, E-mail: xhw@mail.xjtu.edu.cn; Rong, Mingzhe; Wang, Xiaohua, E-mail: liudingxin@gmail.com, E-mail: xhw@mail.xjtu.edu.cn [Centre for Plasma Biomedicine, State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049 (China); Kong, Michael G. [Centre for Plasma Biomedicine, State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049 (China); Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia 23508 (United States); Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia 23529 (United States)

2014-08-15T23:59:59.000Z

387

ASYMPTOTIC MODELLING OF CRYSTALLISATION IN TWO-LAYER SYSTEMS. APPLICATION TO METHANE  

E-Print Network [OSTI]

,b; Skovborg and Rasmussen, 1994 ; Herri et al.,1999). Models generally assume a two-layer configuration which'(z, t) in dissolved gas. Boundary conditions are: c'(0, t) = Cext and c'(, t) = cb(t); Cext is the gas solubility; cb(t) is the bulk concentration. - bulk zone : due to the effect of stirring, concentration

Paris-Sud XI, Université de

388

Transverse oscillations in a single-layer dusty plasma under microgravity V. E. Fortov,2  

E-Print Network [OSTI]

and A. V. Ivlev3 1 Department of Physics and Astronomy, The University of Iowa, Iowa City, Iowa 52242 microgravity conditions. This single layer is confined at a void boundary by a balance of ion drag and electric a source of energy for microparticles. Under microgravity conditions, micropar- ticles are suspended

Goree, John

389

From Neuman to Dirichlet boundary conditions  

SciTech Connect (OSTI)

The Dirichlet boundary conditions for the end-point of the open string define Dp-brane. It is parameterized by the rest of coordinates, with Neuman boundary conditions. The relations between background fields can produce the local gauge symmetries of the world-sheet action. After gauge fixing, some Neuman boundary conditions turn into the Dirichlet ones, decreasing the number of Dp-brane dimensions. The physical Dp-brane is gauge invariant part of the initial one. The gauge invariant coordinates are expressed as linear combinations of the effective coordinates and momenta. This fact explains the origin of non-commutativity and the existence of commutative Dp-brane coordinates.

Nikolic, B.; Sazdovic, B. [Institute of Physics, 11001 Belgrade, P.O.Box 57 (Serbia and Montenegro)

2007-04-23T23:59:59.000Z

390

Winter mixed-layer development in the central Irminger Sea : the effect of strong, intermittent wind events  

E-Print Network [OSTI]

The impact of the Greenland tip jet on the wintertime mixed-layer of the southwest Irminger Sea is investigated using in-situ moored profiler data and a variety of atmospheric data sets. The mixed-layer was observed to ...

Vćge, Kjetil

2006-01-01T23:59:59.000Z

391

Polyport atmospheric gas sampler  

DOE Patents [OSTI]

An atmospheric gas sampler with a multi-port valve which allows for multi, sequential sampling of air through a plurality of gas sampling tubes mounted in corresponding gas inlet ports. The gas sampler comprises a flow-through housing which defines a sampling chamber and includes a gas outlet port to accommodate a flow of gases through the housing. An apertured sample support plate defining the inlet ports extends across and encloses the sampling chamber and supports gas sampling tubes which depend into the sampling chamber and are secured across each of the inlet ports of the sample support plate in a flow-through relation to the flow of gases through the housing during sampling operations. A normally closed stopper means mounted on the sample support plate and operatively associated with each of the inlet ports blocks the flow of gases through the respective gas sampling tubes. A camming mechanism mounted on the sample support plate is adapted to rotate under and selectively lift open the stopper spring to accommodate a predetermined flow of gas through the respective gas sampling tubes when air is drawn from the housing through the outlet port.

Guggenheim, S. Frederic (Teaneck, NJ)

1995-01-01T23:59:59.000Z

392

LES of the adverse-pressure gradient turbulent boundary layer M. Inoue a,  

E-Print Network [OSTI]

at the University of Melbourne wind tunnel where a plate section with zero pressure gradient is followed by section accurate simulations, for example, of separated flow on the wings of airplanes or for flow through turbine such as the amplified wake of the mean velocity profile and the increasing turbulence intensity in the outer region

Marusic, Ivan

393

Synoptic and local influences on boundary layer processes, with an application to California wind power  

E-Print Network [OSTI]

maps showing locations of wind power conversion facilities,of US winds and wind power at 80 m derived fromEvaluation of global wind power. Journal of Geo- physical

Mansbach, David K.

2010-01-01T23:59:59.000Z

394

Study of active control of instability in a boundary layer over a flat plate flow  

E-Print Network [OSTI]

). . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 9 34 Power spectrum and time record at a freestream of 136. 8 mm/s, 2. 5 mm off the bottom wall and 25. 4 mm upstream of the actuator. . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 35 Power specnum and time record at a Ireestream... of 201. 3 mm/s, 2. 5 mm off the bottom wall and 25. 4 mm upstream of the actuator. . . . . . . . . . . . . . . . . . . . . . . . . . . 41 FIGURE Page 36 Power spectrum and time record at a &eestream of 263. 8 mm/s, 2. 5 mm off the bottom wall and 25...

Oryu, Hiroshi

2000-01-01T23:59:59.000Z

395

Numerical prediction of the boundary layers in the flow around a cylinder using a fixed  

E-Print Network [OSTI]

.1. (Webster [We2]): A generic real ellipsoid in Cn with n 3 does not admit any umbilical point. Umbilical]. A natural question arising from [We2] is then to ask whether a generic real ellipsoid in C2 shares the same

Wapperom, Peter

396

Direct Numerical Simulation of Supersonic Turbulent Boundary Layer over a Compression Ramp  

E-Print Network [OSTI]

they impinge on a surface. Yet, STBLI problems are of great importance for the efficient design of scramjet

MartĂ­n, Pino

397

American Institute of Aeronautics and Astronautics Shock/Boundary Layer Interaction Effects of Transverse  

E-Print Network [OSTI]

or regarded as incompressible, or scramjet engine applications where mixing is the primary concern. Reaction

Texas at Arlington, University of

398

American Institute of Aeronautics and Astronautics Shock/Boundary Layer Interaction Effects on Transverse  

E-Print Network [OSTI]

applications, where the freestream is either quiescent or regarded as incompressible, or scramjet engine

Texas at Arlington, University of

399

Preliminary Surface Pressure Measurements of Transitional, Hypersonic Shock Boundary Layer Interactions  

E-Print Network [OSTI]

96-4541 M P Re rms X (T Preliminary Surface Pressure Measurements of Transitional, Hypersonic Shock moves into the hypersonic realm. A critical aspect in designing an airbreathing hy- personic vehicle a number of recent investigations in un- derstanding hypersonic, laminar and turbulent, shock wave

Texas at Arlington, University of

400

Pollution-enhanced reactive chlorine chemistry in the eastern tropical Atlantic boundary layer  

E-Print Network [OSTI]

doi:10.1029/2008GL036666, 2009 Pollution-enhanced reactiveE. S. Saltzman (2009), Pollution-enhanced reactive chlorine5 L08810 LAWLER ET AL. : POLLUTION-ENHANCED CLX IN THE MBL

2009-01-01T23:59:59.000Z

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


401

Recollimation boundary layers as X-ray sources in young stellar jets  

E-Print Network [OSTI]

Young stars accrete mass from circumstellar disks and in many cases, the accretion coincides with a phase of massive outflows, which can be highly collimated. Those jets emit predominantly in the optical and IR wavelength range. However, in several cases X-ray and UV observations reveal a weak but highly energetic component in those jets. X-rays are observed both from stationary regions close to the star and from knots in the jet several hundred AU from the star. In this article we show semi-analytically that a fast stellar wind which is recollimated by the pressure from a slower, more massive disk wind can have the right properties to power stationary X-ray emission. The size of the shocked regions is compatible with observational constraints. Our calculations support a wind-wind interaction scenario for the high energy emission near the base of YSO jets. For the specific case of DG Tau, a stellar wind with a mass loss rate of $5\\cdot10^{-10}\\;M_{\\odot}\\;\\mathrm{yr}^{-1}$ and a wind speed of 800 km s$^{-1}$ ...

Günther, Hans Moritz; Schneider, P C

2014-01-01T23:59:59.000Z

402

Active Control of Instabilities in Laminar BoundaryLayer Flow--Part I: An Overview  

E-Print Network [OSTI]

of the downstream wave which counter (cancel) the evolution of the upstream generated wave. Milling (1981) to generate traveling waves 180 o out of phase, Milling (1981) showed that a wave with a 0.6­percent amplitude resembled a wave shape. By using hot strips to generate and control traveling waves, Liep­ mann

Erlebacher, Gordon

403

Analysis and identification of vortices within a turbulent channel boundary layer flow  

E-Print Network [OSTI]

understanding of the drag reduction mechanism is still lacking. Vortices play an important role in turbulence structure. Nevertheless, the identification of vortices is still unclear, not even a universal definition of a vortex is accepted. In the present study...

Maroni Veiga, Adrian Gaston

2006-08-16T23:59:59.000Z

404

Advances in Differential Equations Volume xx, Number xxx, , Pages xxxx BOUNDARY LAYER FOR A PENALIZATION METHOD  

E-Print Network [OSTI]

experiments. To obtain these results we perform an asymptotic expansion of the solution in the spirit of BKW the BKW method is that one has to obtain very regular solutions on the limit problem. 1.1. Main results

Carbou, Gilles

405

Surface heterogeneity impacts on boundary layer dynamics via energy balance partitioning  

E-Print Network [OSTI]

energy balance partitioning N. A. Brunsell1, D. B. Mechem1, and M. C. Anderson2 1Dept. of Geography, University of Kansas, Lawrence, KS, USA 2Hydrology and Remote Sensing Laboratory, USDA. Beltsville, MD, USA Received: 22 June 2010 – Published in Atmos... responsible for altering surface heat and moisture fluxes. Twelve coupled land surface – large eddy simulation scenarios with four different length scales of surface variability under three different horizontal wind speeds are used in the analysis. The base...

Brunsell, Nathaniel A.; Mechem, David B.; Anderson, M. C.

2011-04-11T23:59:59.000Z

406

Viscous boundary layers for the NavierStokes equations with the Navier slip conditions  

E-Print Network [OSTI]

, such as in aerodynamics (space shuttles covered by tiles), in weather forecast (where trees, buildings, water waves have that the Navier slip­with­friction condition was derived in the kinematic theory of gases by Maxwell. In this case

Iftimie, DragoÂș

407

Viscous boundary layers for the Navier-Stokes equations with the Navier slip conditions  

E-Print Network [OSTI]

, such as in aerodynamics (space shuttles covered by tiles), in weather forecast (where trees, buildings, water waves have that the Navier slip-with-friction condition was derived in the kinematic theory of gases by Maxwell. In this case

Sueur, Franck

408

Understanding the role of organic aerosol in the coastal and remote pacic marine boundary layer  

E-Print Network [OSTI]

2.2.2 FTIR and XRF analyses . . . . . . . . . . . . . .Ray Fluorescence (XRF) . . . . . . . . . . 4.2.3 Quadrupoleof OM (by mass), sum of XRF elements K, Ni, Ca, Fe, Sn, V,

Hawkins, Lelia Nahid

2010-01-01T23:59:59.000Z

409

Reactive Halogens in the Marine Boundary Layer (RHaMBLe): the tropical North Atlantic experiments  

E-Print Network [OSTI]

105, 24191–24204, 2000. Allan, B. J. , Plane J. M. C. , andlayer, Geophys. Res. Lett. , Allan, J. D. , Topping, D. O. ,1,2 , G. McFiggans 3 , J. D. Allan 3,4 , A. R. Baker 5 , S.

2010-01-01T23:59:59.000Z

410

Pollution-enhanced reactive chlorine chemistry in the eastern tropical Atlantic boundary layer  

E-Print Network [OSTI]

ocean surface, calculates particle growth explicitly, and accounts for inter- actions between radiation

2009-01-01T23:59:59.000Z

411

Boundary Layer Forcing of a Semidiurnal, Cross-Channel Seiche WAYNE MARTIN AND PARKER MACCREADY  

E-Print Network [OSTI]

School of Oceanography, University of Washington, Seattle, Washington RICHARD DEWEY School of Earth actual vertical advection of the water mass they are significant because of the potential impact on bio waves (Rhines 1970; Eriksen 1998), nonlinear waves and solitons (Farmer and Armi 1999; Bourgault

MacCready, Parker

412

An efficient approximation for the vibro-acoustic response of a turbulent boundary layer excited panel  

E-Print Network [OSTI]

hal-01004463,version1-11Jun2014 Author manuscript, published in "Journal of Sound and Vibration 264, 4 and the acoustic pressure radiated when a thin elastic plate is immersed in a low Mach number flow of fluid. The mechanical properties of this panel are a Young's modulus E, a Pois- son coefficient and a mass per unit

Boyer, Edmond

413

A BOUNDARY LAYER PROBLEM FOR AN ASYMPTOTIC PRESERVING SCHEME IN THE QUASI-NEUTRAL LIMIT FOR  

E-Print Network [OSTI]

, see [31]. The second application is related to electric arc phenomena on satellite solar panels, see as the asymptotic pre- serving scheme developed in [9] are unstable for general Roe type solvers when the mesh does, the quasi-neutral model is not valid in non quasi-neutral zones and, we have to use different models

Vignal, Marie-HĂ©lĂšne

414

RACORO LONG-TERM, SYSTEMATIC AIRCRAFT OBSERVATIONS OF BOUNDARY LAYER CLOUDS  

E-Print Network [OSTI]

). This type of cloud is common globally, and the Earth's radiative energy balance is particularly sensitive the manuscript for publication acknowledges that the United States Government retains a non-exclusive, paid to do so, for United States Government purposes. BNL-91362-2010-CP #12;

415

Design of an Instrumentation System for a Boundary Layer Transition Wing Glove Experiment  

E-Print Network [OSTI]

side of the glove. Infrared (IR) thermography has been selected as the primary transition detection tool. A heat transfer analysis has shown that solar radiation will warm the surface of the glove above the adiabatic wall temperature and therefore...

Williams, Thomas 1987-

2012-08-23T23:59:59.000Z

416

Synoptic and local influences on boundary layer processes, with an application to California wind power  

E-Print Network [OSTI]

Makarov, Y. , 2007: Wind Integration Issues and So- lutionsexpectations, and integration strategy for any wind powerwind climate and variability. Site design and operation, as well as market integration

Mansbach, David K.

2010-01-01T23:59:59.000Z

417

An Examination of Configurations for Using Infrared to Measure Boundary Layer Transition  

E-Print Network [OSTI]

as an external source and circulating fluid inside of the airfoil. Furthermore, ABS plastic and aluminum airfoils are tested with and without coatings such as black paint and surface wraps. The results show that thermal conduction within the model and surface...

Freels, Justin Reed

2012-10-19T23:59:59.000Z

418

Boundary-Layer Meteorol DOI 10.1007/s10546-014-9914-6  

E-Print Network [OSTI]

dispersion model that includes time variations of the turbulent kinetic energy dissipation rate is proposed is consistent with field measurements inside a pine forest and with published dissipation rate measurements Institute for Air Research (NILU), Oslo, Norway 123 #12;T. Duman et al. 1 Introduction High Reynolds

Katul, Gabriel

419

Aerosol-Cloud-Precipitation Interactions in the Trade Wind Boundary Layer.  

E-Print Network [OSTI]

??This dissertation includes an overview of aerosol, cloud, and precipitation properties associated with shallow marine cumulus clouds observed during the Barbados Aerosol Cloud Experiment (BACEX,… (more)

Jung, Eunsil

2012-01-01T23:59:59.000Z

420

Boundary-layer transition on broad cones rotating in an imposed axial flow  

E-Print Network [OSTI]

for the fuel efficiency through increased noise and energy dissipation, and for projectile applications films of optical and electrical materials on substrates in the electrochemical industry. Such reactors

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


421

CATALYZED COMBUSTION IN A FLAT PLATE BOUNDARY LAYER II. NUMERICAL CALCULATIONS  

E-Print Network [OSTI]

at Simulated Gas Turbine Combustor Operating Conditions",on the use of catalytic combustors for aircraft gas turbineof prototype catalytic combustor configurations. studies are

Schefer, R.

2010-01-01T23:59:59.000Z

422

Eos,Vol. 85, No. 23, 8 June 2004 enhanced convergence,boundary layer desta-  

E-Print Network [OSTI]

-dynamics and aerosol-micro- physics arguments. Human-related activities associated with transportation,energy of the week in NewYork City.This cycle was hypothesized to be related to increased trans- portation activity,the impact of urbanization on net primary productivity (NPP) and its consequences for carbon balance and food

Segall, Paul

423

UBL/CLU-ESCOMPTE : THE URBAN BOUNDARY LAYER FIELD EXPERIMENT OVER MARSEILLE AND THE DATA BASE  

E-Print Network [OSTI]

) thé comparison of thé Town Energy Balance model with thé data obtained over thé city center, (d) thé-comparison of energy flux instrumentations, (b) thé quality évaluation of thé measurements at thé urban stations, (c, among which two on ships, and two in trucks. Thé surface energy budget was measured at 9 sites. Thé

Boyer, Edmond

424

Improving tropical and subtropical boundary layer cloudiness in the NCEP GFS  

E-Print Network [OSTI]

, as well as in the Community Earth System Model (CESM, http://www.cesm.ucar.edu/), using the relative

Bretherton, Chris

425

Boundary-Layer Meteorol DOI 10.1007/s10546-010-9529-5  

E-Print Network [OSTI]

). A considerable amount of isotope research has focused on the condensed phase. However, the analysis of water compared using EC-TDL and traditional eddy-covariance and infrared gas analyser techniques over a soybean

Minnesota, University of

426

The aerodynamic characteristics of an airfoil utilizing boundary layer and circulation control  

E-Print Network [OSTI]

AND DISCUSSION 22 Effects on Lift Effects on Drag 33 Effects on Pitching Moment 36 Accuracy of Data 37 Flow Interference 38 111 Chapte r VI CONCLUSIONS BIB LIO GRAPHY APPENDIX . Page 41 43 44 Table l. Aerodynamic Characteristics for Varying... control. The suction slot was 0. 065 inches wide and 2. 50 inches long in the spanwise direction. In order to measure the pressure distribution on the model, static pressure orifices were installed in the model surface at the spanwise centerline...

Boothe, Edward Milton

2012-06-07T23:59:59.000Z

427

Eddy-resolving Lidar Measurements and Numerical Simulations of the Convective Internal Boundary Layer  

E-Print Network [OSTI]

in speed. The vertical gradient of wind-speed decreases offshore because of strong vertical mixing caused correlation functions and winds derived from horizontal (PPI) and vertical (RHI) scans of the VIL during Lake.4 0.5 0.6 0.7 DOWNSTREAM WIND SPEEDS FROM RHI SCANS ON 13 JANUARY 1998 SPATIALLY RESOLVED 5-m WINDS

Eloranta, Edwin W.

428

Synoptic and local influences on boundary layer processes, with an application to California wind power  

E-Print Network [OSTI]

th percentiles of daily wind speeds (vertical axis) largelyand warm SST. Mean vertical pro?les of wind speed from EPICspeed at the wind farm sites, since inversion strength is largely controlled by the vertical

Mansbach, David K.

2010-01-01T23:59:59.000Z

429

Understanding the role of organic aerosol in the coastal and remote pacic marine boundary layer  

E-Print Network [OSTI]

than 600 m). Vertical velocity and wind speed profiles are? v ), vertical velocity (w ) and horizontal wind speed (WS)? v ), vertical velocity (w ), horizontal wind speed (WS),

Hawkins, Lelia Nahid

2010-01-01T23:59:59.000Z

430

CATALYZED COMBUSTION IN A FLAT PLATE BOUNDARY LAYER I. EXPERIMENTAL MEASUREMENTS AND COMPARISON WITH NUMERICAL CALCULATIONS  

E-Print Network [OSTI]

l~ Roberts, "Catathermal Combustion: A New Process for Lm'l-significant gas phase combustion is induced by the presenceInternational) on Combustion (to be published), The

Robben, R.

2010-01-01T23:59:59.000Z

431

CATALYZED COMBUSTION IN A FLAT PLATE BOUNDARY LAYER II. NUMERICAL CALCULATIONS  

E-Print Network [OSTI]

D.G. , Fourteenth Sympo- sium (International) on Combustion,The Combustion Institute, Pittsburgh, 107 (1973). Wilson,Program for Calculation of Combustion Reaction Equilibrium

Schefer, R.

2010-01-01T23:59:59.000Z

432

The development of a low velocity wind tunnel with instrumentation for boundary layer investigations  

E-Print Network [OSTI]

W>?rH 23 pressure pickups? The Statham Laboratories built and calibrated a pressure transducer with a 0 to ~ 0 .015 psi range. Essentially, the transducer is a wheatstone bridge made from strain gages mounted in a diaphragm in such a manner...

Massey, John Robert

1958-01-01T23:59:59.000Z

433

Synoptic and local influences on boundary layer processes, with an application to California wind power  

E-Print Network [OSTI]

means fall in greater windpower classes than does Palmcontrast, would only fall in windpower classes 1, 3, 2, and

Mansbach, David K

2010-01-01T23:59:59.000Z

434

DOE/SC-ARM/TR-132 Planetary Boundary Layer (PBL) Height Value  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct: CrudeOffice ofINL is a U.S. Department of422

435

Synoptic and local influences on boundary layer processes, with an application to California wind power  

E-Print Network [OSTI]

California o?shore wind energy potential. Renewable Energy,2008: Ex- ploring wind energy potential o? the Californiafor estimates of wind power potential. Journal of Applied

Mansbach, David K.

2010-01-01T23:59:59.000Z

436

Synoptic and local influences on boundary layer processes, with an application to California wind power  

E-Print Network [OSTI]

corresponding to extreme winds for di?erent stations andin turn would lead to extreme downscaled wind speed changeextreme quintiles or more exacting classi?cations of wind

Mansbach, David K.

2010-01-01T23:59:59.000Z

437

Boundary-Layer Meteorol DOI 10.1007/s10546-011-9682-5  

E-Print Network [OSTI]

, Momentum, and Energy Exchange Rates of a Uniform Crop Situated in an Extensive Screenhouse Mario B Science+Business Media B.V. 2011 Abstract The area of crops cultivated in extensive screenhouses heat released or taken up by crops within such protected environments can substantially alter

Katul, Gabriel

438

Understanding the role of organic aerosol in the coastal and remote pacic marine boundary layer  

E-Print Network [OSTI]

sources, especially copper smelters, along the Peruvian andpossibly because the Chilean copper smelters have a stronger

Hawkins, Lelia Nahid

2010-01-01T23:59:59.000Z

439

DOE research on atmospheric aerosols  

SciTech Connect (OSTI)

Atmospheric aerosols are the subject of a significant component of research within DOE`s environmental research activities, mainly under two programs within the Department`s Environmental Sciences Division, the Atmospheric Radiation Measurement (ARM) Program and the Atmospheric Chemistry Program (ACP). Research activities conducted under these programs include laboratory experiments, field measurements, and theoretical and modeling studies. The objectives and scope of these programs are briefly summarized. The ARM Program is the Department`s major research activity focusing on atmospheric processes pertinent to understanding global climate and developing the capability of predicting global climate change in response to energy related activities. The ARM approach consists mainly of testing and improving models using long-term measurements of atmospheric radiation and controlling variables at highly instrumented sites in north central Oklahoma, in the Tropical Western Pacific, and on the North Slope of Alaska. Atmospheric chemistry research within DOE addresses primarily the issue of atmospheric response to emissions from energy-generation sources. As such this program deals with the broad topic known commonly as the atmospheric source-receptor sequence. This sequence consists of all aspects of energy-related pollutants from the time they are emitted from their sources to the time they are redeposited at the Earth`s surface.

Schwartz, S.E.

1995-11-01T23:59:59.000Z

440

Space Science : Atmosphere Greenhouse Effect  

E-Print Network [OSTI]

Space Science : Atmosphere Greenhouse Effect Part-5a Solar + Earth Spectrum IR Absorbers Grey Atmosphere Greenhouse Effect #12;Radiation: Solar and Earth Surface B"(T) Planck Ideal Emission Integrate at the carbon cycle #12;However, #12;Greenhouse Effect is Complex #12;PLANETARY ENERGY BALANCE G+W fig 3-5

Johnson, Robert E.

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


441

Containment atmosphere response (CAR) program. Second status report. [HTGR  

SciTech Connect (OSTI)

This report contains a summary of the work performed under the Containment Atmosphere Response (CAR) Program of the High-Temperature Gas-Cooled Reactor (HTGR) Safety Research Task since the publication of the previous status report (February 1978). The work concentrated on development of models describing containment phenomena during core heatup in support of probabilistic risk assessment studies. Models were completed for fission product iodine sorption on coated surfaces, diffusivity and retentivity of untreated concrete, iodine interaction with condensing steam on the containment atmosphere boundaries, and the cleanup filter system. These models were incorporated into a new computer program called CARCAS, a substantial extension of the CNTB computer program, and applied to Accident Initiation and Progression Analysis for Phase II core heatup sequences. Development was begun on models describing the postulated behavior of particulate fission products or aerosols within and leaking out of the containment.

Landoni, J.A.

1980-03-01T23:59:59.000Z

442

Topological analysis of the grain boundary space  

E-Print Network [OSTI]

Grain boundaries and their networks have a profound influence on the functional and structural properties of every class of polycrystalline materials and play a critical role in structural evolution and phase transformations. ...

Patala, Srikanth

2011-01-01T23:59:59.000Z

443

Brownian walkers within subdiffusing territorial boundaries  

E-Print Network [OSTI]

Inspired by the collective phenomenon of territorial emergence, whereby animals move and interact through the scent marks they deposit, we study the dynamics of a 1D Brownian walker in a random environment consisting of confining boundaries that are themselves diffusing anomalously. We show how to reduce, in certain parameter regimes, the non-Markovian, many-body problem of territoriality to the analytically tractable one-body problem studied here. The mean square displacement (MSD) of the 1D Brownian walker within subdiffusing boundaries is calculated exactly and generalizes well known results when the boundaries are immobile. Furthermore, under certain conditions, if the boundary dynamics are strongly subdiffusive, we show the appearance of an interesting non-monotonicity in the time dependence of the MSD, giving rise to transient negative diffusion.

Luca Giuggioli; Jonathan R. Potts; Stephen Harris

2011-02-04T23:59:59.000Z

444

Nonlinear boundary value problem of magnetic insulation  

E-Print Network [OSTI]

On the basis of generalization of upper and lower solution method to the singular two point boundary value problems, the existence theorem of solutions for the system, which models a process of magnetic insulation in plasma is proved.

A. V. Sinitsyn

2000-09-09T23:59:59.000Z

445

Oxygen-reducing catalyst layer  

DOE Patents [OSTI]

An oxygen-reducing catalyst layer, and a method of making the oxygen-reducing catalyst layer, where the oxygen-reducing catalyst layer includes a catalytic material film disposed on a substrate with the use of physical vapor deposition and thermal treatment. The catalytic material film includes a transition metal that is substantially free of platinum. At least one of the physical vapor deposition and the thermal treatment is performed in a processing environment comprising a nitrogen-containing gas.

O'Brien, Dennis P. (Maplewood, MN); Schmoeckel, Alison K. (Stillwater, MN); Vernstrom, George D. (Cottage Grove, MN); Atanasoski, Radoslav (Edina, MN); Wood, Thomas E. (Stillwater, MN); Yang, Ruizhi (Halifax, CA); Easton, E. Bradley (Halifax, CA); Dahn, Jeffrey R. (Hubley, CA); O'Neill, David G. (Lake Elmo, MN)

2011-03-22T23:59:59.000Z

446

Climatological simulations of ozone and atmospheric aerosols in the Greater Cairo region  

SciTech Connect (OSTI)

An integrated chemistry-climate model (RegCM4-CHEM) simulates present-day climate, ozone and tropospheric aerosols over Egypt with a focus on Greater Cairo (GC) region. The densley populated GC region is known for its severe air quality issues driven by high levels of anthropogenic pollution in conjuction with natural sources such as dust and agricultural burning events. We find that current global emission inventories underestimate key pollutants such as nitrogen oxides and anthropogenic aerosol species. In the GC region, average-ground-based NO2 observations of 40-60 ppb are substantially higher than modeled estimates (5-10 ppb), likely due to model grid resolution, improper boundary layer representation, and poor emissions inventories. Observed ozone concentrations range from 35 ppb (winter) to 80 ppb (summer). The model reproduces the seasonal cycle fairly well, but modeled summer ozone is understimated by approximately 15 ppb and exhibits little interannual variability. For aerosols, springtime dust events dominate the seasonal aerosol cycle. The chemistry-climate model captures the springtime peak aerosol optical depth (AOD) of 0.7-1 but is slightly greater than satellite-derived AOD. Observed AOD decreases in the summer and increases again in the fall due to agricultural burning events in the Nile Delta, yet the model underestimates this fall observed AOD peak, as standard emissions inventories underestimate this burning and the resulting aerosol emissions. Our comparison of modeled gas and particulate phase atmospheric chemistry in the GC region indicates that improved emissions inventories of mobile sources and other anthropogenic activities are needed to improve air quality simulations in this region.

Steiner, A. L.; Tawfik, A. B.; Shalaby, A.; Zakey, A. S.; Abdel Wahab, M. M.; Salah, Z.; Solmon, F.; Sillman, S.; Zaveri, Rahul A.

2014-04-16T23:59:59.000Z

447

The Deep Layers of Sunspot Umbrae  

E-Print Network [OSTI]

We model the deepest observable layers of dark sunspot umbral atmospheres in terms of an empirical model which equally describes observed near infrared continuum intensities and line profiles. We use the umbral continuum intensity at 1.67 nm and the three C I lines at 1,6888, 1,7449 and 1,7456 nm to model the deep layers near the minimum of H- absorption. We find that a radiative equilibrium stratification yields the best compromise between continuum and C I line observations. We determine the effective temperature from the umbral and photospheric flux ratio by down-scaling the monochromatic photospheric flux with the umbral contrast for each frequency. The thus obtained monochromatic umbral flux and the photospheric one are integratied over the whole frequency range, yielding the ratio of total umbral and photospheric flux, which gives 3560 K < T_eff < 3780 K. We assume for our model M3 T_eff=3750 K and fit M3 to the theoretical model by Meyer et al. (1974). Comparison of the model's 'nabla' gradient w...

Stellmacher, Goetz

2012-01-01T23:59:59.000Z

448

Effects of Transition Metals on the Grain Boundary Cohesion in...  

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

Transition Metals on the Grain Boundary Cohesion in Tungsten. Effects of Transition Metals on the Grain Boundary Cohesion in Tungsten. Abstract: We report on the effects of...

449

Friction of Steel Sliding Under Boundary Lubrication Regime in...  

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

Friction of Steel Sliding Under Boundary Lubrication Regime in Commercial Gear Oils at Elevated Temperatures Friction of Steel Sliding Under Boundary Lubrication Regime in...

450

Incorporating local boundary conditions into nonlocal theories  

E-Print Network [OSTI]

We study nonlocal equations from the area of peridynamics on bounded domains. In our companion paper, we discover that, on $\\mathbb{R}^n$, the governing operator in peridynamics, which involves a convolution, is a bounded function of the classical (local) governing operator. Building on this, we define an abstract convolution operator on bounded domains. The abstract convolution operator is a function of the classical operator, defined by a Hilbert basis available due to the purely discrete spectrum of the latter. As governing operator of the nonlocal equation we use a function of the classical operator, this allows us to incorporate local boundary conditions into nonlocal theories. For the homogeneous wave equation with the considered boundary conditions, we prove that continuity is preserved by time evolution. We give explicit solution expressions for the initial value problems with prominent boundary conditions such as periodic, antiperiodic, Neumann, and Dirichlet. In order to connect to the standard convolution, we give an integral representation of the abstract convolution operator. We present additional "simple" convolutionsbased on periodic and antiperiodic boundary conditions that lead Neumann and Dirichlet boundary conditions. We present a numerical study of the solutions of the wave equation. For discretization, we employ a weak formulation based on a Galerkin projection and use piecewise polynomials on each element which allows discontinuities of the approximate solution at the element borders. We study convergence order of solutions with respect to polynomial order and observe optimal convergence. We depict the solutions for each boundary condition.

Burak Aksoylu; Horst Reinhard Beyer; Fatih Celiker

2014-11-12T23:59:59.000Z

451

Atmospheric Dispersion at Spatial Resolutions Below Mesoscale for university of Tennessee SimCenter at Chattanooga: Final Report  

SciTech Connect (OSTI)

In Year 1 of this project, items 1.1 and 1.2 were addressed, as well as item 2.2. The baseline parallel computational simulation tool has been refined significantly over the timeline of this project for the purpose of atmospheric dispersion and transport problems; some of these refinements are documented in Chapter 3. The addition of a concentration transport capability (item 1.2) was completed, along with validation and usage in a highly complex urban environment. Multigrid capability (item 2.2) was a primary focus of Year 1 as well, regardless of the fact that it was scheduled for Year 2. It was determined by the authors that due to the very large nature of the meshes required for atmospheric simulations at mesoscale, multigrid was a key enabling technology for the rest of the project to be successful. Therefore, it was addressed early according to the schedule laid out in the original proposal. The technology behind the multigrid capability is discussed in detail in Chapter 5. Also in Year 1, the issue of ground topography specification is addressed. For simulations of pollutant transport in a given region, a key prerequisite is the specification of the detailed ground topography. The local topography must be placed into a form suitable for generating an unstructured grid both on the topography itself and the atmospheric volume above it; this effort is documented in Chapter 6. In Year 2 of this project, items 1.3 and 2.1 were addressed. Weather data in the form of wind speeds, relative humidity, and baseline pollution levels may be input into the code in order to improve the real-world fidelity of the solutions. Of course, the computational atmospheric boundary layer (ABL) boundary condition developed in Year 1 may still be used when necessary. Cloud cover may be simulated via the levels of actinic flux allowed in photochemical reactions in the atmospheric chemistry model. The primary focus of Year 2 was the formulation of a multispecies capability with included chemical reactions (item 2.1). This proved to be a very arduous task, taking the vast majority of the time and personnel allocation for Year Two. The addition of this capability and related verification is documented in Chapter 7. A discussion of available tropospheric chemistry models is located in Chapter 8; and, a technology demonstrator for the full multispecies capability is detailed in Chapter 9. Item 2.3 has been partially addressed, in that the computation of sensitivity derivatives have been incorporated in the Tenasi code [7]. However, it has not been utilized in this project in order to compute probability distribution functions for pollutant deposition. In order to completely address the integration of weather and sensor data into the code (item 1.3) and integrate with existing sensor networks (item 3.1), a customizable interface was established. Weather data is most commonly available via a real database, and as such, support for accessing these databases is present in the solver source code. For integration functionality, a method of dynamic code customization was developed in Year 3, which is documented in Chapter 11.

Dr. David Whitfield; Dr. Daniel Hyams

2009-09-14T23:59:59.000Z

452

Method of deforming a biaxially textured buffer layer on a textured metallic substrate and articles therefrom  

DOE Patents [OSTI]

The present invention provides methods and biaxially textured articles having a deformed epitaxial layer formed therefrom for use with high temperature superconductors, photovoltaic, ferroelectric, or optical devices. A buffer layer is epitaxially deposited onto biaxially-textured substrates and then mechanically deformed. The deformation process minimizes or eliminates grooves, or other irregularities, formed on the buffer layer while maintaining the biaxial texture of the buffer layer. Advantageously, the biaxial texture of the buffer layer is not altered during subsequent heat treatments of the deformed buffer. The present invention provides mechanical densification procedures which can be incorporated into the processing of superconducting films through the powder deposit or precursor approaches without incurring unfavorable high-angle grain boundaries.

Lee, Dominic F. (Knoxville, TN); Kroeger, Donald M. (Knoxville, TN); Goyal, Amit (Knoxville, TN)

2000-01-01T23:59:59.000Z

453

Response of a boundless two-layer ocean to atmospheric disturbancesResponse of a boundless two-layer ocean to atmospheric disturbances  

E-Print Network [OSTI]

- )? (8) and a y 2 Q . = 2 r - 2 - ? cur l T >? w j y ^ ^ y a t a x - - The set of equations (7)> (8) and (9) are formally the same as the equations for homogeneous water# ?10- In terms of the normal mode functions R_, . and Q. ? j ? jx... /' (*o) and for V > C , i r / / c ~ v S 3 -n 9 \\ I, U , Q , t ) = i ----- J | /------------- - - KA), (41) for t ?*> 00 1 c2 - V2 sin24 c2 - V2 1 * . V2 sin24 2 r 2 j n T c Z ?\\*J ^2 _ c2 for l^ >| | > sin C...

Kajiura, Kinjiro; Kajiura, Kinjiro

1958-01-01T23:59:59.000Z

454

Al{sub 2}O{sub 3} multi-density layer structure as a moisture permeation barrier deposited by radio frequency remote plasma atomic layer deposition  

SciTech Connect (OSTI)

Al{sub 2}O{sub 3} films deposited by remote plasma atomic layer deposition have been used for thin film encapsulation of organic light emitting diode. In this study, a multi-density layer structure consisting of two Al{sub 2}O{sub 3} layers with different densities are deposited with different deposition conditions of O{sub 2} plasma reactant time. This structure improves moisture permeation barrier characteristics, as confirmed by a water vapor transmission rate (WVTR) test. The lowest WVTR of the multi-density layer structure was 4.7 Ś 10{sup ?5} gm{sup ?2} day{sup ?1}, which is one order of magnitude less than WVTR for the reference single-density Al{sub 2}O{sub 3} layer. This improvement is attributed to the location mismatch of paths for atmospheric gases, such as O{sub 2} and H{sub 2}O, in the film due to different densities in the layers. This mechanism is analyzed by high resolution transmission electron microscopy, elastic recoil detection, and angle resolved X-ray photoelectron spectroscopy. These results confirmed that the multi-density layer structure exhibits very good characteristics as an encapsulation layer via location mismatch of paths for H{sub 2}O and O{sub 2} between the two layers.

Jung, Hyunsoo [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Samsung Display Co. Ltd., Tangjeong, Chungcheongnam-Do 336-741 (Korea, Republic of); Jeon, Heeyoung [Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Choi, Hagyoung; Ham, Giyul; Shin, Seokyoon [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Jeon, Hyeongtag, E-mail: hjeon@hanyang.ac.kr [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Department of Nano-scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

2014-02-21T23:59:59.000Z

455

Laser Atmospheric Studies with VERITAS  

E-Print Network [OSTI]

As a calibrated laser pulse propagates through the atmosphere, the amount of Rayleigh-scattered light arriving at the VERITAS telescopes can be calculated precisely. This technique was originally developed for the absolute calibration of ultra-high-energy cosmic-ray fluorescence telescopes but is also applicable to imaging atmospheric Cherenkov telescopes (IACTs). In this paper, we present two nights of laser data taken with the laser at various distances away from the VERITAS telescopes and compare it to Rayleigh scattering simulations.

C. M. Hui; for the VERITAS collaboration

2007-09-25T23:59:59.000Z

456

Might Carbon-Atmosphere White Dwarfs Harbour a New Type of Pulsating Star?  

E-Print Network [OSTI]

In the light of the recent and unexpected discovery of a brand new type of white dwarfs, those with carbon-dominated atmospheres, we examine the asteroseismological potential of such stars. The motivation behind this is based on the observation that past models of carbon-atmosphere white dwarfs have partially ionized outer layers that bear strong resemblance with those responsible for mode excitation in models of pulsating DB (helium-atmosphere) and pulsating DA (hydrogen-atmosphere) white dwarfs. Our exciting main result is that, given the right location in parameter space, some carbon-atmosphere white dwarfs are predicted to show pulsational instability against gravity modes. We are eagerly waiting the results of observational searches for luminosity variations in these stars.

G. Fontaine; P. Brassard; P. Dufour

2008-03-14T23:59:59.000Z

457

Solution to the Boltzmann equation for layered systems for current perpendicular to the planes  

SciTech Connect (OSTI)

Present theories of giant magnetoresistance (GMR) for current perpendicular to the planes (CPP) are based on an extremely restricted solution to the Boltzmann equation that assumes a single free electron band structure for all layers and all spin channels. Within this model only the scattering rate changes from one layer to the next. This model leads to the remarkable result that the resistance of a layered material is simply the sum of the resistances of each layer. We present a solution to the Boltzmann equation for CPP for the case in which the electronic structure can be different for different layers. The problem of matching boundary conditions between layers is much more complicated than in the current in the planes (CIP) geometry because it is necessary to include the scattering-in term of the Boltzmann equation even for the case of isotropic scattering. This term couples different values of the momentum parallel to the planes. When the electronic structure is different in different layers there is an interface resistance even in the absence of intermixing of the layers. The size of this interface resistance is affected by the electronic structure, scattering rates, and thicknesses of nearby layers. For Co-Cu, the calculated interface resistance and its spin asymmetry is comparable to that measured at low temperature in sputtered samples. (c) 2000 American Institute of Physics.

Butler, W. H. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Zhang, X.-G. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); MacLaren, J. M. [Tulane University, New Orleans, Louisiana 70018 (United States)] [Tulane University, New Orleans, Louisiana 70018 (United States)

2000-05-01T23:59:59.000Z

458

Metal precipitation at grain boundaries in silicon: Dependence on grain boundary character and dislocation decoration  

E-Print Network [OSTI]

are combined to determine the dependence of metal silicide precipitate formation on grain boundary character and microstructure in multicrystalline silicon mc-Si . Metal silicide precipitate decoration is observed to increase the local metal silicide precipitate concentrations at various types of grain boundaries, identifying clear

459

Surface and grain boundary scattering in nanometric Cu thin films: A quantitative analysis including twin boundaries  

SciTech Connect (OSTI)

The relative contributions of various defects to the measured resistivity in nanocrystalline Cu were investigated, including a quantitative account of twin-boundary scattering. It has been difficult to quantitatively assess the impact twin boundary scattering has on the classical size effect of electrical resistivity, due to limitations in characterizing twin boundaries in nanocrystalline Cu. In this study, crystal orientation maps of nanocrystalline Cu films were obtained via precession-assisted electron diffraction in the transmission electron microscope. These orientation images were used to characterize grain boundaries and to measure the average grain size of a microstructure, with and without considering twin boundaries. The results of these studies indicate that the contribution from grain-boundary scattering is the dominant factor (as compared to surface scattering) leading to enhanced resistivity. The resistivity data can be well-described by the combined Fuchs–Sondheimer surface scattering model and Mayadas–Shatzkes grain-boundary scattering model using Matthiessen's rule with a surface specularity coefficient of p?=?0.48 and a grain-boundary reflection coefficient of R?=?0.26.

Barmak, Katayun [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 and Department of Materials Science and Engineering and Materials Research Science and Engineering Center, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Darbal, Amith [Department of Materials Science and Engineering and Materials Research Science and Engineering Center, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Ganesh, Kameswaran J.; Ferreira, Paulo J. [Materials Science and Engineering, The University of Texas at Austin, 1 University Station, Austin, Texas 78712 (United States); Rickman, Jeffrey M. [Department of Materials Science and Engineering and Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015 (United States); Sun, Tik; Yao, Bo; Warren, Andrew P.; Coffey, Kevin R., E-mail: kb2612@columbia.edu [Department of Materials Science and Engineering, University of Central Florida, 4000 Central Florida Boulevard, Orlando, Florida 32816 (United States)

2014-11-01T23:59:59.000Z

460

Fragmentation Energetics of Clusters Relevant to Atmospheric...  

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

of Clusters Relevant to Atmospheric New Particle Formation. Fragmentation Energetics of Clusters Relevant to Atmospheric New Particle Formation. Abstract: The exact mechanisms by...

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


461

Do grain boundaries in nanophase metals slide?  

SciTech Connect (OSTI)

Nanophase metallic materials show a maximum in strength as grain size decreases to the nano scale, indicating a break down of the Hall-Petch relation. Grain boundary sliding, as a possible accommodation mechanisms, is often the picture that explain computer simulations results and real experiments. In a recent paper, Bringa et al. Science 309, 1838 (2005), we report on the observation of an ultra-hard behavior in nanophase Cu under shock loading, explained in terms of a reduction of grain boundary sliding under the influence of the shock pressure. In this work we perform a detailed study of the effects of hydrostatic pressure on nanophase Cu plasticity and find that it can be understood in terms of pressure dependent grain boundary sliding controlled by a Mohr-Coulomb law.

Bringa, E M; Leveugle, E; Caro, A

2006-10-27T23:59:59.000Z

462

Wireless boundary monitor system and method  

DOE Patents [OSTI]

A wireless boundary monitor system used to monitor the integrity of a boundary surrounding an area uses at least two housings having at least one transmitting means for emitting ultrasonic pressure waves to a medium. Each of the housings has a plurality of receiving means for sensing the pressure waves in the medium. The transmitting means and the receiving means of each housing are aimable and communicably linked. At least one of the housings is equipped with a local alarm means for emitting a first alarm indication whereby, when the pressure waves propagating from a transmitting means to a receiving means are sufficiently blocked by an object a local alarm means or a remote alarm means or a combination thereof emit respective alarm indications. The system may be reset either manually or automatically. This wireless boundary monitor system has useful applications in both indoor and outdoor environments.

Haynes, Howard D. (Knoxville, TN); Ayers, Curtis W. (Kingston, TN)

1997-01-01T23:59:59.000Z

463

Casimir Pistons with General Boundary Conditions  

E-Print Network [OSTI]

In this work we analyze the Casimir energy and force for a scalar field endowed with general self-adjoint boundary conditions propagating in a higher dimensional piston configuration. The piston is constructed as a direct product $I\\times N$, with $I=[0,L]\\subset\\mathbb{R}$ and $N$ a smooth, compact Riemannian manifold with or without boundary. The study of the Casimir energy and force for this configuration is performed by employing the spectral zeta function regularization technique. The obtained analytic results depend explicitly on the spectral zeta function associated with the manifold $N$ and the parameters describing the general boundary conditions imposed. These results are then specialized to the case in which the manifold $N$ is a $d$-dimensional sphere.

Guglielmo Fucci

2014-10-16T23:59:59.000Z

464

Wireless boundary monitor system and method  

DOE Patents [OSTI]

A wireless boundary monitor system used to monitor the integrity of a boundary surrounding an area uses at least two housings having at least one transmitting means for emitting ultrasonic pressure waves to a medium. Each of the housings has a plurality of receiving means for sensing the pressure waves in the medium. The transmitting means and the receiving means of each housing are aimable and communicably linked. At least one of the housings is equipped with a local alarm means for emitting a first alarm indication whereby, when the pressure waves propagating from a transmitting means to a receiving means are sufficiently blocked by an object a local alarm means or a remote alarm means or a combination thereof emit respective alarm indications. The system may be reset either manually or automatically. This wireless boundary monitor system has useful applications in both indoor and outdoor environments. 4 figs.

Haynes, H.D.; Ayers, C.W.

1997-12-09T23:59:59.000Z

465

Nanoengineering Catalyst Supports via Layer-by Layer Surface Functionalization  

SciTech Connect (OSTI)

Recent progress in the layer-by-layer surface modification of oxides for the preparation of highly active and stable gold nanocatalysts is briefly reviewed. Through a layer-by-layer surface modification approach, the surfaces of various catalyst supports including both porous and nonporous silica materials and TiO{sub 2} nanoparticles were modified with monolayers or multilayers of distinct metal oxide ultra-thin films. The surface-modified materials were used as supports for Au nanoparticles, resulting in highly active nanocatalysts for low-temperature CO oxidation. Good stability against sintering under high-temperature treatment was achieved for a number of the Au catalysts through surface modification of the support material. The surface modification of supports can be a viable route to control both the composition and structure of support and nanoparticle interfaces, thereby tailoring the stability and activity of the supported catalyst systems.

Yan, Wenfu [ORNL; Mahurin, Shannon Mark [ORNL; Overbury, Steven {Steve} H [ORNL; Dai, Sheng [ORNL

2006-01-01T23:59:59.000Z

466

D0 layer 0 innermost layer of silicon microstrip tracker  

SciTech Connect (OSTI)

A new inner layer silicon strip detector has been built and will be installed in the existing silicon microstrip tracker in D0. They report on the motivation, design, and performance of this new detector.

Hanagaki, K.; /Fermilab

2006-01-01T23:59:59.000Z

467

Process for forming epitaxial perovskite thin film layers using halide precursors  

DOE Patents [OSTI]

A process for forming an epitaxial perovskite-phase thin film on a substrate. This thin film can act as a buffer layer between a Ni substrate and a YBa.sub.2 Cu.sub.3 O.sub.7-x superconductor layer. The process utilizes alkali or alkaline metal acetates dissolved in halogenated organic acid along with titanium isopropoxide to dip or spin-coat the substrate which is then heated to about 700.degree. C. in an inert gas atmosphere to form the epitaxial film on the substrate. The YBCO superconductor can then be deposited on the layer formed by this invention.

Clem, Paul G. (Albuquerque, NM); Rodriguez, Mark A. (Albuquerque, NM); Voigt, James A. (Corrales, NM); Ashley, Carol S. (Albuquerque, NM)

2001-01-01T23:59:59.000Z

468

Layer-By-Layer Assembled Hybrid Film of Carbon Nanotubes/Iron...  

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

By-Layer Assembled Hybrid Film of Carbon NanotubesIron Oxide Nanocrystals for Reagentless Electrochemical Detection of Layer-By-Layer Assembled Hybrid Film of Carbon Nanotubes...

469

The ARM Atmospheric Emitted Radiance Interferometer (AERI): Status and  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 and NbSe2 .2004 North Slope ofPreliminary Assessments

470

The Fundamental Limitation of Atmospheric Remote Sensing by Dissection of  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 and NbSe2DifferentThe Five Fastest

471

1. Integrated Database 2. Boundary Analysis  

E-Print Network [OSTI]

1. Integrated Database 2. Boundary Analysis Melinda Laituri Colorado State University June 2011 #12 data Model package/ Analysis technique #12;Establishing a Database What are our scales? What are our units of analysis? What commonality do we have? What is the nature of our data? What

472

The Importance of Carbon Footprint Estimation Boundaries  

E-Print Network [OSTI]

The Importance of Carbon Footprint Estimation Boundaries H . S C O T T M A T T H E W S , C H R I and organizations are pursuing "carbon footprint" projects to estimate their own contributions to global climate change. Protocol definitions from carbon registries help organizations analyze their footprints

Kammen, Daniel M.

473

New Boundaries | Issue 16 | June 2013 Treatmentandsupport  

E-Print Network [OSTI]

industries with their development of the strongest, lightest material. Moving from the work our engineers about contemporary society, on page 22. For more research stories, visit our website www cells that form part of the human immune system) attacking a cancer cell #12;NewBoundaries|June2013

Anderson, Jim

474

Metal precipitation at grain boundaries in silicon: Dependence on grain boundary character and dislocation decoration  

SciTech Connect (OSTI)

Synchrotron-based analytical microprobe techniques, electron backscatter diffraction, and defect etching are combined to determine the dependence of metal silicide precipitate formation on grain boundary character and microstructure in multicrystalline silicon (mc-Si). Metal silicide precipitate decoration is observed to increase with decreasing atomic coincidence within the grain boundary plane (increasing {sigma} values). A few low-{sigma} boundaries contain anomalously high metal precipitate concentrations, concomitant with heavy dislocation decoration. These results provide direct experimental evidence that the degree of interaction between metals and structural defects in mc-Si can vary as a function of microstructure, with implications for mc-Si device performance and processing.

Buonassisi, T.; Istratov, A. A.; Pickett, M. D.; Marcus, M. A.; Ciszek, T. F.; Weber, E. R. [Department of Materials Science and Engineering, University of California, Berkeley, California 94720 and Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); National Renewable Energy Laboratory, Golden, Colorado 80401 (United States); Department of Materials Science and Engineering, University of California, Berkeley, California 94720 and Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

2006-07-24T23:59:59.000Z

475

General Comparison of Power Loss in Single-Layer and Multi-Layer Windings  

E-Print Network [OSTI]

General Comparison of Power Loss in Single-Layer and Multi-Layer Windings M. E. Dale C. R. Sullivan the IEEE. #12;General Comparison of Power Loss in Single-Layer and Multi-Layer Windings Magdalena E. Dale

476

E-Print Network 3.0 - automated spin-assisted layer-by-layer...  

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

A novel hydrothermal layer-by-layer... control in an aqueous system, we explored a novel hydrothermal layer-by- layer processing method11 Source: Schiff, Eric A. - Department of...

477

SIO 217a Atmospheric and Climate Sciences I: Atmospheric Thermodynamics  

E-Print Network [OSTI]

. Radiant Energy. Radiative Transfer. Transport.) 10-Oct W 3 More Transfer Processes 15-Oct M 4 4 Gas. Equation of State. Hydrostatic Equilibrium.) 3-Oct W 2 2.11 First and Second Laws and Characteristics. Precipitation Processes. Radiative Transfer in a Cloudy Atmosphere. Fogs, Stratus

Russell, Lynn

478

Linked Environments for Atmospheric Discovery Linked Environments for Atmospheric  

E-Print Network [OSTI]

Unidata Program Center #12;Linked Environments for Atmospheric Discovery The Team: 9 institutions and 105 MethodologyTraditional NWP Methodology STATIC OBSERVATIONS Radar Data Mobile Mesonets Surface Observations Satellites The Process is Entirely Prescheduled and Serial; It Does NOT Respond to the Weather! The Process

479

NETL SOFC: Atmospheric Pressure Systems  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Opticalhttp://www.fnal.gov/directorate/nalcal/nalcal02_07_05_files/nalcal.gifA Comparison95519LocalizedWaterTerryAtmospheric

480

The limited growth of vegetated shear layers  

E-Print Network [OSTI]

In contrast to free shear layers, which grow continuously downstream, shear layers generated by submerged vegetation grow only to a finite thickness. Because these shear layers are characterized by coherent vortex structures ...

Ghisalberti, M.

Note: This page contains sample records for the topic "atmospheric boundary layer" from the National Library of EnergyBeta (NLEBeta).
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481

Hybrid window layer for photovoltaic cells  

DOE Patents [OSTI]

A novel photovoltaic solar cell and method of making the same are disclosed. The solar cell includes: at least one absorber layer which could either be a lightly doped layer or an undoped layer, and at least a doped window-layers which comprise at least two sub-window-layers. The first sub-window-layer, which is next to the absorber-layer, is deposited to form desirable junction with the absorber-layer. The second sub-window-layer, which is next to the first sub-window-layer, but not in direct contact with the absorber-layer, is deposited in order to have transmission higher than the first-sub-window-layer.

Deng, Xunming (Syvania, OH); Liao, Xianbo (Toledo, OH); Du, Wenhui (Toledo, OH)

2011-10-04T23:59:59.000Z

482

Hybrid window layer for photovoltaic cells  

DOE Patents [OSTI]

A novel photovoltaic solar cell and method of making the same are disclosed. The solar cell includes: at least one absorber layer which could either be a lightly doped layer or an undoped layer, and at least a doped window-layers which comprise at least two sub-window-layers. The first sub-window-layer, which is next to the absorber-layer, is deposited to form desirable junction with the absorber-layer. The second sub-window-layer, which is next to the first sub-window-layer, but not in direct contact with the absorber-layer, is deposited in order to have transmission higher than the first-sub-window-layer.

Deng, Xunming (Syvania, OH)

2010-02-23T23:59:59.000Z

483

Hybrid window layer for photovoltaic cells  

DOE Patents [OSTI]

A novel photovoltaic solar cell and method of making the same are disclosed. The solar cell includes: at least one absorber layer which could either be a lightly doped layer or an undoped layer, and at least a doped window-layers which comprise at least two sub-window-layers. The first sub-window-layer, which is next to the absorber-layer, is deposited to form desirable junction with the absorber-layer. The second sub-window-layer, which is next to the first sub-window-layer, but not in direct contact with the absorber-layer, is deposited in order to have transmission higher than the first-sub-window-layer.

Deng, Xunming (Sylvania, OH); Liao, Xianbo (Toledo, OH); Du, Wenhui (Toledo, OH)

2011-02-01T23:59:59.000Z

484

Dynamics of multiple double layers in high pressure glow discharge in a simple torus  

SciTech Connect (OSTI)

Parametric characterization of multiple double layers is done during high pressure glow discharge in a toroidal vessel of small aspect ratio. Although glow discharge (without magnetic field) is known to be independent of device geometry, but the toroidal boundary conditions are conducive to plasma growth and eventually the plasma occupy the toroidal volume partially. At higher anode potential, the visibly glowing spots on the body of spatially extended anode transform into multiple intensely luminous spherical plasma blob structures attached to the tip of the positive electrode. Dynamics of multiple double layers are observed in argon glow discharge plasma in presence of toroidal magnetic field. The radial profiles of plasma parameters measured at various toroidal locations show signatures of double layer formation in our system. Parametric dependence of double layer dynamics in presence of toroidal magnetic field is presented here.

Kumar Paul, Manash, E-mail: manashkr@gmail.com [Department of Physics, National Institute of Technology Agartala, Tripura–799 046 (India); Sharma, P. K.; Thakur, A.; Kulkarni, S. V.; Bora, D. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat–382 428 (India)

2014-06-15T23:59:59.000Z

485

Thin-Layer Spectroelectrochemistry on an Aqueous Microdrop. | EMSL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 andThe1 MembersStability| EMSLforThin

486

Hydrogen in magnesium palladium thin layer structures.  

E-Print Network [OSTI]

??In this thesis, the study of hydrogen storage, absorption and desorption in magnesium layers is described. The magnesium layers have a thickness of 50-500 nm… (more)

Kruijtzer, G.L.

2008-01-01T23:59:59.000Z

487

Integrable Boundaries, Conformal Boundary Conditions and A-D-E Fusion Rules  

E-Print Network [OSTI]

The $sl(2)$ minimal theories are labelled by a Lie algebra pair $(A,G)$ where $G$ is of $A$-$D$-$E$ type. For these theories on a cylinder we conjecture a complete set of conformal boundary conditions labelled by the nodes of the tensor product graph $A\\otimes G$. The cylinder partition functions are given by fusion rules arising from the graph fusion algebra of $A\\otimes G$. We further conjecture that, for each conformal boundary condition, an integrable boundary condition exists as a solution of the boundary Yang-Baxter equation for the associated lattice model. The theory is illustrated using the $(A_4,D_4)$ or 3-state Potts model.

Roger E. Behrend; Paul A. Pearce; Jean-Bernard Zuber

1998-07-20T23:59:59.000Z

488

HEATING THE ATMOSPHERE ABOVE SUNSPOTS  

E-Print Network [OSTI]

become fragmented and twisted, and where they generate the necessary energy to heat the solar coronaHEATING THE ATMOSPHERE ABOVE SUNSPOTS David Alexander and Neal E. Hurlburt Lockheed Martin Solar, University of Cambridge, Cambridge, CB3 9EW, UK Abstract We present our results of a hybrid model of sunspots

Rucklidge, Alastair

489

13, 90179049, 2013 Stable atmospheric  

E-Print Network [OSTI]

ACPD 13, 9017­9049, 2013 Stable atmospheric methane in the 2000s I. Pison et al. Title Page Utrecht, Utrecht University, Utrecht, the Netherlands 3 SRON Netherlands Institute for Space Research, Utrecht, the Netherlands 4 Vrije Universiteit, Department of Systems Ecology, Amsterdam, the Netherlands 5

Paris-Sud XI, Université de

490

Space Science: Atmosphere Thermal Structure  

E-Print Network [OSTI]

Space Science: Atmosphere Part -2 Thermal Structure Review tropospheres Absorption of Radiation Adiabatic Lapse Rate ~ 9 K/km Slightly smaller than our estimate Pressure ~3000ft under ocean surface thickness (positive up) is the solar zenith angle Fs is the solar energy flux at frequency (when

Johnson, Robert E.

491

Pathintegral Monte Carlo simulation of the second layer of 4 He adsorbed on graphite Marlon Pierce and Efstratios Manousakis  

E-Print Network [OSTI]

boundaries are in agreement with heat capacity and torsional oscillator measurements, and demonstrate years. Extensive heat capacity measurements 4,5 of the first six layers have been performed of increasing density, a superfluid liquid phase, a A73A7 commensurate solid phase that is registered

Manousakis, Efstratios

492

12th AIAA/CEAS Aeroacoustics Conference, May 8--10, 2006, Cambridge, Massachusetts PML absorbing boundary condition for non-linear  

E-Print Network [OSTI]

Perfectly Matched Layer (PML) absorbing boundary condition for the compressible non- linear Navier a viscous flow over a circular cylinder are presented. Satisfactory results demonstrated that the proposed that the absorbing zone is theoretically reflectionless for multi-dimensional linear waves of any angle and frequency

Hu, Fang Q.

493

Conditions for establishing quasistable double layers in the Earth's auroral upward current region  

SciTech Connect (OSTI)

The strength and stability of simulated double layers at the ionosphere-auroral cavity boundary have been studied as a function of cold ionospheric electron temperature and density. The simulations are performed with an open boundary one-dimensional particle-in- cell (PIC) simulation and are initialized by imposing a density cavity within the simulation domain. The PIC simulation includes H{sup +} and O{sup +} ion beams, a hot H{sup +} background population, cold ionospheric electrons, and a hot electron population. It is shown that a double layer remains quasistable for a variety of initial conditions and plasma parameters. The average potential drop of the double layer is found to increase as the cold electron temperature decreases. However, in terms of cold electron density, the average potential drop of the double layer is found to increase up to some critical cold electron density and decreases above this value. Comparisons with FAST observations are made and agreement is found between simulation results and observations in the shape and width of the double layer. This study helps put a constraint on the plasma conditions in which a DL can be expected to form and remain quasistable.

Main, D. S. [Department of Physics, John Brown University, Siloam Springs, Arkansas 72761 (United States); Newman, D. L. [Center for Integrated Plasma Studies, University of Colorado, Boulder, Colorado 80309 (United States); Ergun, R. E. [Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303 (United States)

2010-12-15T23:59:59.000Z

494

Nuclear Power Plant Containment Pressure Boundary Research  

SciTech Connect (OSTI)

Research to address aging of the containment pressure boundary in light-water reactor plants is summarized. This research is aimed at understanding the significant factors relating occurrence of corrosion, efficacy of inspection, and structural capacity reduction of steel containment and liners of concrete containment. This understanding will lead to improvements in risk-informed regulatory decision making. Containment pressure boundary components are described and potential aging factors identified. Quantitative tools for condition assessments of aging structures to maintain an acceptable level of reliability over the service life of the plant are discussed. Finally, the impact of aging (i.e., loss of shell thickness due to corrosion) on steel containment fragility for a pressurized water reactor ice-condenser plant is presented.

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

1999-09-15T23:59:59.000Z

495

ARM ARM Atmospheric Radiation Measurement Atmospheric Radiation Measurement  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)Productssondeadjustsondeadjust Documentation DataProductswsicloudwsicloudsummarygifAOS Processing

496

Layered architecture for quantum computing  

E-Print Network [OSTI]

We develop a layered quantum computer architecture, which is a systematic framework for tackling the individual challenges of developing a quantum computer while constructing a cohesive device design. We discuss many of the prominent techniques for implementing circuit-model quantum computing and introduce several new methods, with an emphasis on employing surface code quantum error correction. In doing so, we propose a new quantum computer architecture based on optical control of quantum dots. The timescales of physical hardware operations and logical, error-corrected quantum gates differ by several orders of magnitude. By dividing functionality into layers, we can design and analyze subsystems independently, demonstrating the value of our layered architectural approach. Using this concrete hardware platform, we provide resource analysis for executing fault-tolerant quantum algorithms for integer factoring and quantum simulation, finding that the quantum dot architecture we study could solve such problems on the timescale of days.

N. Cody Jones; Rodney Van Meter; Austin G. Fowler; Peter L. McMahon; Jungsang Kim; Thaddeus D. Ladd; Yoshihisa Yamamoto

2012-09-27T23:59:59.000Z

497

Stick-Slip Control in Nanoscale Boundary Lubrication by Surface Wettability  

E-Print Network [OSTI]

We study the effect of atomic scale surface-lubricant interactions on nanoscale boundary-lubricated friction, by considering two example surfaces - hydrophilic mica and hydrophobic graphene - confining thin layers of water in molecular dynamics simulations. We observe stick-slip dynamics for thin water films confined by mica sheets, involving periodic breaking-reforming transitions of atomic scale capillary water bridges formed around the potassium ions of mica. However, only smooth sliding without stick-slip events is observed for water confined by graphene, as well as for thicker water layers confined by mica. Thus, our results illustrate how atomic scale details affect the wettability of the confining surfaces, and consequently control the presence or absence of stick-slip dynamics in nanoscale friction.

Wei Chen; Adam S. Foster; Mikko J. Alava; Lasse Laurson

2015-02-13T23:59:59.000Z

498

[0268] First Galley Proofs MULTIPLICITIES, BOUNDARY POINTS,  

E-Print Network [OSTI]

, multiplicity, extreme point, sharp point, boundary point. c Ð , Zagreb Paper OaM-0268 1 #12;2 W.S. CHEUNG NUMERICAL RANGES WAI-SHUN CHEUNG, XUHUA LIU AND TIN-YAU TAM (Communicated by C.-K. Li) Abstract, XUHUA LIU AND T.Y. TAM Given W(A), Embry [8] introduced M = M (A) := {x Cn : x Ax = x x}. In general

Tam, Tin-Yau

499

Technology adaptation and boundary management in bona fide virtual groups.  

E-Print Network [OSTI]

In this research project composed of multiple case studies, I focused on how bona fide virtual groups appropriated multiple media to facilitate group boundary construction and boundary management, which are preconditions of group identity formation...

Zhang, Huiyan

2006-04-12T23:59:59.000Z

500

Thermodynamic stability and implications of anisotropic boundary particles  

E-Print Network [OSTI]

(cont.) Generally, a boundary is nonplanar in the neighborhood of an attached particle--even when anisotropic interfacial free energies do not produce faceting-and maintains a icKy = 0 while the boundary particles maintain ...

Siem, Ellen J. (Ellen Jane), 1979-

2005-01-01T23:59:59.000Z