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


1

ARM - Measurement - Latent heat flux  

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

govMeasurementsLatent heat flux govMeasurementsLatent heat flux ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Latent heat flux The time rate of flow for the specific enthalpy difference between two phases of a substance at the same temperature, typically water. Categories Surface Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments CO2FLX : Carbon Dioxide Flux Measurement Systems ECOR : Eddy Correlation Flux Measurement System EBBR : Energy Balance Bowen Ratio Station

2

Intercomparison of Various Surface Latent Heat Flux Fields  

Science Conference Proceedings (OSTI)

The Japanese Ocean Flux Data Sets with use of Remote Sensing Observations (J-OFURO) latent heat flux field is compared with the Hamburg Ocean–Atmosphere Parameters and Fluxes from Satellite Data (HOAPS), the Goddard Satellite-Based Surface ...

Masahisa Kubota; Atsuko Kano; Hidenori Muramatsu; Hiroyuki Tomita

2003-02-01T23:59:59.000Z

3

Sensible and Latent Heat Flux Measurements over the Ocean  

Science Conference Proceedings (OSTI)

This papar presents an extensive act of sensible heat (Reynolds flux and dissipation methods) and latent heat (dissipation method) flux measurements from a stable deep water tower and from ships on the deep sea. Operational difficulties ...

W. G. Large; S. Pond

1982-05-01T23:59:59.000Z

4

Intraseasonal Latent Heat Flux Based on Satellite Observations  

Science Conference Proceedings (OSTI)

Weekly average satellite-based estimates of latent heat flux (LHTFL) are used to characterize spatial patterns and temporal variability in the intraseasonal band (periods shorter than 3 months). As expected, the major portion of intraseasonal ...

Semyon A. Grodsky; Abderrahim Bentamy; James A. Carton; Rachel T. Pinker

2009-09-01T23:59:59.000Z

5

A Comparison of Latent Heat Fluxes over Global Oceans for Four Flux Products  

Science Conference Proceedings (OSTI)

The ocean surface latent heat flux (LHF) plays an essential role in global energy and water cycle variability. In this study, monthly LHF over global oceans during 1992–93 are compared among Goddard Satellite-Based Surface Turbulent Fluxes, ...

Shu-Hsien Chou; Eric Nelkin; Joe Ardizzone; Robert M. Atlas

2004-10-01T23:59:59.000Z

6

The Relationship between Sea Surface Temperature and Latent Heat Flux in the Equatorial Pacific  

Science Conference Proceedings (OSTI)

Moored buoy data from the equatorial Pacific are analyzed to investigate the relationship between sea surface temperature (SST) and latent heat flux from the ocean. It is found that at low SST the latent heat flux increases with SST; at high SST ...

Guang Jun Zhang; Michael J. Mcphaden

1995-03-01T23:59:59.000Z

7

Latent and Sensible Heat Flux Anomalies over the Northern Oceans: The Connection to Monthly Atmospheric Circulation  

Science Conference Proceedings (OSTI)

The influence of the atmospheric circulation on monthly anomalies of ocean surface latent and sensible heat fluxes is explored. The fluxes are estimated using bulk formulas applied to a set of about four decades of marine observations over 1946–...

Daniel R. Cayan

1992-04-01T23:59:59.000Z

8

Rectified Wind Forcing and Latent Heat Flux Produced by the Madden–Julian Oscillation  

Science Conference Proceedings (OSTI)

Rectification of (Madden–Julian oscillation) MJO-induced wind speed and latent heat flux variations across the tropical Indian and western Pacific Oceans is estimated using 51 yr of NCEP–NCAR reanalysis. The rectified wind speed anomaly is ...

Toshiaki Shinoda; Harry H. Hendon

2002-12-01T23:59:59.000Z

9

Mixtures of Gaussians for Uncertainty Description in Bivariate Latent Heat Flux Proxies  

Science Conference Proceedings (OSTI)

This paper proposes a new probabilistic approach for describing uncertainty in the ensembles of latent heat flux proxies. The proxies are obtained from hourly Bowen ratio and satellite-derived measurements, respectively, at several locations in ...

R. Wójcik; Peter A. Troch; H. Stricker; P. Torfs; E. Wood; H. Su; Z. Su

2006-06-01T23:59:59.000Z

10

Evaluation of Latent Heat Flux Fields from Satellites and Models during SEMAPHORE  

Science Conference Proceedings (OSTI)

Latent heat fluxes were derived from satellite observations in the region of Structure des Echanges Mer–Atmosphère, Propriétés des Hétérogénéités Océaniques: Recherche Expérimentale (SEMAPHORE), which was conducted near the Azores islands in the ...

Denis Bourras; W. Timothy Liu; Laurence Eymard; Wenqing Tang

2003-02-01T23:59:59.000Z

11

A Comparison of Sensible and Latent Heat Flux Calculations Using the Bowen Ratio and Aerodynamic Methods  

Science Conference Proceedings (OSTI)

An analysis technique is outlined that calculates the sensible and latent heat fluxes by the Bowen ratio and aerodynamic methods, using profile measurements at any number of heights. Field measurements at two sites near Churchill, Manitoba, ...

David H. Halliwell; Wayne R. Rouse

1989-08-01T23:59:59.000Z

12

Satellite-derived Surface Latent Heat Fluxes in a Rapidly Intensifying Marine Cyclone  

Science Conference Proceedings (OSTI)

The aim of this article is to estimate surface latent heat fluxes in the vicinity of a rapidly deepening cyclone before and during its period of most rapid intensification. This is done with a bulk parameterization scheme and remotely sensed ...

Douglas K. Miller; Kristina B. Katsaros

1992-07-01T23:59:59.000Z

13

Latent Heat Flux Profiles from Collocated Airborne Water Vapor and Wind Lidars during IHOP_2002  

Science Conference Proceedings (OSTI)

Latent heat flux profiles in the convective boundary layer (CBL) are obtained for the first time with the combination of the Deutsches Zentrum für Luft- und Raumfahrt (DLR) water vapor differential absorption lidar (DIAL) and the NOAA high ...

C. Kiemle; G. Ehret; A. Fix; M. Wirth; G. Poberaj; W. A. Brewer; R. M. Hardesty; C. Senff; M. A. LeMone

2007-04-01T23:59:59.000Z

14

Spatially Distributed CO2, Sensible, and Latent Heat Fluxes Over the  

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

Spatially Distributed CO2, Sensible, and Latent Heat Fluxes Over the Spatially Distributed CO2, Sensible, and Latent Heat Fluxes Over the Southern Great Plains Berry, Joseph Carnegie Inst.of Washington Riley, William Lawrence Berkeley National Laboratory Biraud, Sebastien Lawrence Berkeley National Laboratory Torn, Margaret Lawrence Berkeley National Laboratory Fischer, Marc Lawrence Berkeley National Laboratory Category: Atmospheric State and Surface Vegetation strongly influences the spatial distribution of surface sensible and latent heat fluxes, and also impacts the ecosystem to atmosphere CO2 exchanges. We describe here a methodology to estimate surface energy fluxes and Net Ecosystem Exchange (NEE) of CO2 continuously over the Southern Great Plains, using (1) data from the Atmospheric Radiation Measurement (ARM) program in Oklahoma and Kansas; (2) meteorological forcing data from

15

Estimates of Surface Humidity and Latent Heat Fluxes over Oceans from SSM/I Data  

Science Conference Proceedings (OSTI)

Monthly averages of daily latent heat fluxes over the oceans for February and August 1988 are estimated using a stability-dependent bulk scheme. Daily fluxes are computed from daily SSM/I (Special Sensor Microwave/Imager) wind speeds and EOF-...

Shu-Hsien Chou; Robert M. Atlas; Chung-Lin Shie; Joe Ardizzone

1995-08-01T23:59:59.000Z

16

Averaging-Related Biases in Monthly Latent Heat Fluxes  

Science Conference Proceedings (OSTI)

Seasonal-to-multidecadal applications that require ocean surface energy fluxes often require accuracies of surface turbulent fluxes to be 5 W m?2 or better. While there is little doubt that uncertainties in the flux algorithms and input data can ...

Paul J. Hughes; Mark A. Bourassa; Jeremy J. Rolph; Shawn R. Smith

2012-07-01T23:59:59.000Z

17

Snow Temperature Changes within a Seasonal Snowpack and their Relationship to Turbulent Fluxes of Sensible and Latent Heat  

Science Conference Proceedings (OSTI)

Snowpack temperatures from a subalpine forest below Niwot Ridge, Colorado are examined with respect to atmospheric conditions and the 30-min above-canopy and subcanopy eddy covariance fluxes of sensible Qh and latent Qe heat. In the lower snowpack,...

Sean P. Burns; Noah P. Molotch; Mark W. Williams; John F. Knowles; Brian Seok; Russell K. Monson; Andrew A. Turnipseed; Peter D. Blanken

18

The Sensitivity of Latent Heat Flux to Changes in the Radiative Forcing: A Framework for Comparing Models and Observations  

Science Conference Proceedings (OSTI)

A climate model must include an accurate surface physics scheme in order to examine the interactions between the land and atmosphere. Given an increase in the surface radiative forcing, the sensitivity of latent heat flux to available energy ...

Jonathan M. Winter; Elfatih A. B. Eltahir

2010-05-01T23:59:59.000Z

19

Variations of Sensible and Latent Heat Fluxes from a Great Lakes Buoy and Associated Synoptic Weather Patterns  

Science Conference Proceedings (OSTI)

An investigation of sensible and latent heat fluxes and their relation to synoptic weather events was performed using hourly meteorological measurements from National Data Buoy Center buoy 45003, located in northern Lake Huron, during April–...

Neil F. Laird; David A. R. Kristovich

2002-02-01T23:59:59.000Z

20

Comparison between Global Latent Heat Flux Computed from Multisensor (SSM/I and AVHRR) and from In Situ Data  

Science Conference Proceedings (OSTI)

The accurate estimate of the latent heat flux (LHF) is important to understand better the coupling between the atmosphere and the ocean and their respective circulation. In the near future, the availability of satellite-derived datasets over long ...

Didier Jourdan; Catherine Gautier

1995-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

The Sensitivity of Latent Heat Flux to Changes in the Radiative Forcing: A Framework for Comparing Models and Observations  

E-Print Network (OSTI)

A climate model must include an accurate surface physics scheme in order to examine the interactions between the land and atmosphere. Given an increase in the surface radiative forcing, the sensitivity of latent heat flux ...

Winter, Jonathan (Jonathan Mark)

22

Mean and Variability of the WHOI Daily Latent and Sensible Heat Fluxes at In Situ Flux Measurement Sites in the Atlantic Ocean  

Science Conference Proceedings (OSTI)

Daily latent and sensible heat fluxes for the Atlantic Ocean from 1988 to 1999 with 1° × 1° resolution have been recently developed at Woods Hole Oceanographic Institution (WHOI) by using a variational object analysis approach. The present study ...

Lisan Yu; Robert A. Weller; Bomin Sun

2004-06-01T23:59:59.000Z

23

Underestimation of Latent and Sensible Heat Fluxes above the Agulhas Current in NCEP and ECMWF Analyses  

Science Conference Proceedings (OSTI)

The Agulhas Current is the major western boundary current of the Southern Hemisphere. South of Africa it retroflects back into the southwest Indian Ocean, transporting relatively warm water into the midlatitudes. Large sensible and latent heat ...

M. Rouault; C. J. C. Reason; J. R. E. Lutjeharms; A. C. M. Beljaars

2003-02-01T23:59:59.000Z

24

Turbulent Fluxes in the Hurricane Boundary Layer. Part II: Latent Heat Flux  

Science Conference Proceedings (OSTI)

As part of the recent ONR-sponsored Coupled Boundary Layer Air–Sea Transfer (CBLAST) Departmental Research Initiative, an aircraft was instrumented to carry out direct turbulent flux measurements in the high wind boundary layer of a hurricane. ...

William M. Drennan; Jun A. Zhang; Jeffrey R. French; Cyril McCormick; Peter G. Black

2007-04-01T23:59:59.000Z

25

Comparisons of sensible and latent heat fluxes using surface and aircraft data over adjacent wet and dry surfaces  

SciTech Connect

In June 1991, a field study of surface fluxes of latent and sensible heat over heterogeneous surfaces was carried out near Boardman, Oregon (Doran et al., 1992). The object of the study was to develop improved methods of extrapolating from local measurements of fluxes to area-averaged values suitable for use in general circulation models (GCMs) applied to climate studies. A grid element in a GCM is likely to encompass regions whose fluxes vary significantly from one surface type to another. The problem of integrating these fluxes into a single, representative value for the whole element is not simple, and describing such a flux in terms of flux-gradient relationships, as is often done, presents additional difficulties.

Doran, J.C.; Hubbe, J.M.; Shaw, W.J. (Pacific Northwest Lab., Richland, WA (United States)); Baldocchi, D.D.; Crawford, T.L.; Dobosy, R.J.; Meyers, T.J. (National Oceanic and Atmospheric Administration, Oak Ridge, TN (United States). Air Resources Lab. Atmospheric Turbulence and Diffusion Div.)

1992-01-01T23:59:59.000Z

26

Characterization of Turbulent Latent and Sensible Heat Flux Exchange between the Atmosphere and Ocean in MERRA  

Science Conference Proceedings (OSTI)

Turbulent fluxes of heat and moisture across the atmosphere–ocean interface are fundamental components of the earth’s energy and water balance. Characterizing both the spatiotemporal variability and the fidelity of these exchanges of heat and ...

J. Brent Roberts; Franklin R. Robertson; Carol A. Clayson; Michael G. Bosilovich

2012-02-01T23:59:59.000Z

27

An Error Analysis of the Thornthwaite-Holzman Equations for Estimating Sensible and Latent Heat Fluxes over Crop and Forest Canopies  

Science Conference Proceedings (OSTI)

Computations of sensible and latent heat fluxes over forest and crop canopies using the Thornthwaite-Holzman equations require an a priori knowledge of roughness and data displacement heights. If the values of these parameters are not ...

O. E. Thompson; R. T. Pinker

1981-03-01T23:59:59.000Z

28

Latent Heat Flux and Canopy Conductance Based on Penman–Monteith, Priestley–Taylor Equation, and Bouchet’s Complementary Hypothesis  

Science Conference Proceedings (OSTI)

A novel method is presented to analytically resolve the terrestrial latent heat flux (?E) and conductances (boundary layer gB and surface gS) using net radiation (RN), ground heat flux (G), air temperature (Ta), and relative humidity (RH). This ...

Kaniska Mallick; Andrew Jarvis; Joshua B. Fisher; Kevin P. Tu; Eva Boegh; Dev Niyogi

2013-04-01T23:59:59.000Z

29

Validation of Satellite-Derived Daily Latent-Heat Flux over the South China Sea, Compared with Observations and Five Products  

Science Conference Proceedings (OSTI)

We have developed the South China Sea (SCS) daily satellite-derived latent-heat flux (SCSSLH) for the period of 1998 to 2011 at 0.25°×0.25° resolution using data mainly from the Tropical Rain Measuring Mission (TRMM) Microwave Imager (TMI). Flux-...

Dongxiao Wang; Lili Zeng; Xixi Li; Ping Shi

30

Improving Latent and Sensible Heat Flux Estimates for the Atlantic Ocean (1988–99) by a Synthesis Approach  

Science Conference Proceedings (OSTI)

A new daily latent and sensible flux product developed at the Woods Hole Oceanographic Institution (WHOI) with 1° × 1° resolution for the Atlantic Ocean (65°S–65°N) for the period from 1988 to 1999 was presented. The flux product was developed by ...

Lisan Yu; Robert A. Weller; Bomin Sun

2004-01-01T23:59:59.000Z

31

Latent heat accumulating greenhouse  

Science Conference Proceedings (OSTI)

This invention relates to a latent heat accumulating greenhouse utilizing solar heat. The object of the invention is to provide a greenhouse which is simple in construction, of high efficiency for heat absorbing and capable of much absorbing and accumulating of heat. A heat accumulating chamber partitioned by transparent sheets is provided between the attic and a floor surface facing north in the greenhouse. A blower fan is disposed to confront an opening provided at the lower portion in said heat accumulating chamber. Also, in the heat accumulating chamber, a heat accumulating unit having a large number of light transmitting windows and enclosing a phase transformation heat accumulating material such as CaC1/sub 2/.6H/sub 2/O, Na/sub 2/SO/sub 4/.10H/sub 2/O therein is detachably suspended in a position close to windowpanes at the north side.

Yano, N.; Ito, H.; Makido, I.

1985-04-16T23:59:59.000Z

32

The Role of Low-Level Moisture Convergence and Ocean Latent Heat Fluxes in the Madden and Julian Oscillation: An Observational Analysis Using ISCCP Data and ECMWF Analyses  

Science Conference Proceedings (OSTI)

This paper examines whether or not low-level moisture convergence and surface latent heat flux act as forcing mechanisms of the Madden and Julian oscillation (MJO), as it is proposed by the theories of wave-CISK (conditional instability of the ...

Charles Jones; Bryan C. Weare

1996-12-01T23:59:59.000Z

33

Satellite Estimates of Wind Speed and Latent Heat Flux over the Global Oceans  

Science Conference Proceedings (OSTI)

Surface fluxes of momentum, freshwater, and energy across the air–sea interface determine oceanic circulation and its variability at all timescales. The goal of this paper is to estimate and examine some ocean surface flux variables using ...

Abderrahim Bentamy; Kristina B. Katsaros; Alberto M. Mestas-Nuñez; William M. Drennan; Evan B. Forde; Hervé Roquet

2003-02-01T23:59:59.000Z

34

High-Resolution Satellite Surface Latent Heat Fluxes in North Atlantic Hurricanes  

Science Conference Proceedings (OSTI)

This study presents a new high-resolution satellite-derived ocean surface flux product, XSeaFlux, which is evaluated for its potential use in hurricane studies. The XSeaFlux employs new satellite datasets using improved retrieval methods, and uses ...

Jiping Liu; Judith A. Curry; Carol Anne Clayson; Mark A. Bourassa

2011-09-01T23:59:59.000Z

35

An Empirical Latent Heat Flux Parameterization for the Noah Land Surface Model  

Science Conference Proceedings (OSTI)

Proper partitioning of the surface energy fluxes that drive the evolution of the planetary boundary layer in numerical weather prediction models requires an accurate representation of initial land surface conditions. Unfortunately, soil ...

Christopher M. Godfrey; David J. Stensrud

2010-08-01T23:59:59.000Z

36

Estimation of Sensible and Latent Heat Fluxes from Soil Surface Temperature Using a Linear Air-Land Heat Transfer Model  

Science Conference Proceedings (OSTI)

The authors present a linearized model of the heat transfer between the soil layer and the atmosphere. Using this model, the moisture availability at the surface can be estimated from the diurnal variations of the soil surface temperature and ...

Fujio Kimura; Yugo Shimizu

1994-04-01T23:59:59.000Z

37

Retrieval of Latent Heating from TRMM Measurements  

Science Conference Proceedings (OSTI)

Rainfall is a fundamental process within the Earth's hydrological cycle because it represents a principal forcing term in surface water budgets, while its energetics corollary, latent heating, is the principal source of atmospheric diabatic ...

W-K. Tao; E. A. Smith; R. F. Adler; A. Y. Hou; R. Meneghini; J. Simpson; Z. S. Haddad; T. Iguchi; S. Satoh; R. Kakar; T. N. Krishnamurti; C. D. Kummerow; S. Lang; K. Nakamura; T. Nakazawa; K. Okamoto; S. Shige; W. S. Olson; Y. Takayabu; G. J. Tripoli; S. Yang

2006-11-01T23:59:59.000Z

38

Latent Heat Induced Energy Transformations during Cyclogenesis  

Science Conference Proceedings (OSTI)

Using real-data numerical simulation experiments, latent heat induced energy transformations during the development of the wave cyclone of 20 May 1977 are investigated. During a 24 h period over 5 cm of precipitation fell despite baroclinically ...

C. B. Chang; D. J. Pepkey; C. W. Kreitzberg

1984-02-01T23:59:59.000Z

39

Photovoltaic roof heat flux  

E-Print Network (OSTI)

of ~24°C, indicating that heat conduction was small. T h i sday, indicating large heat conduction a n d storage. Control2.1.3 showed that conduction heat flux through the roof was

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

40

Oceanic Heat Flux Calculation  

Science Conference Proceedings (OSTI)

The authors review the procedure for the direct calculation of oceanic heat flux from hydrographic measurements and set out the full “recipe” that is required.

Sheldon Bacon; Nick Fofonoff

1996-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Comparing Aircraft-Based Remotely Sensed Energy Balance Fluxes with Eddy Covariance Tower Data Using Heat Flux Source Area Functions  

Science Conference Proceedings (OSTI)

In an effort to better evaluate distributed airborne remotely sensed sensible and latent heat flux estimates, two heat flux source area (footprint) models were applied to the imagery, and their pixel weighting/integrating functionality was ...

JoséL. Chávez; Christopher M. U. Neale; Lawrence E. Hipps; John H. Prueger; William P. Kustas

2005-12-01T23:59:59.000Z

42

Diurnal Covariation in Soil Heat Flux and Net Radiation  

Science Conference Proceedings (OSTI)

Diurnal variation in soil heat flux is a key constraint on the amount of energy available for sensible and latent heating of the lower troposphere. Many studies have demonstrated that soil heat flux G is strongly correlated with net radiation Rn. ...

Joseph A. Santanello Jr.; Mark A. Friedl

2003-06-01T23:59:59.000Z

43

Intercomparisons of Air–Sea Heat Fluxes over the Southern Ocean  

Science Conference Proceedings (OSTI)

Consistency and discrepancy of air–sea latent and sensible heat fluxes (LHF and SHF, respectively) in the Southern Ocean for current-day flux products are analyzed from climatology and interannual-to-decadal variability perspectives. Five flux ...

Jiping Liu; Tingyin Xiao; Liqi Chen

2011-02-01T23:59:59.000Z

44

Probability Distribution Characteristics for Surface Air–Sea Turbulent Heat Fluxes over the Global Ocean  

Science Conference Proceedings (OSTI)

To analyze the probability density distributions of surface turbulent heat fluxes, the authors apply the two-parametric modified Fisher–Tippett (MFT) distribution to the sensible and latent turbulent heat fluxes recomputed from 6-hourly NCEP–NCAR ...

Sergey K. Gulev; Konstantin Belyaev

2012-01-01T23:59:59.000Z

45

Optical heat flux gauge  

DOE Patents (OSTI)

A heat flux gauge comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable. 9 figs.

Noel, B.W.; Borella, H.M.; Cates, M.R.; Turley, W.D.; MacArthur, C.D.; Cala, G.C.

1989-06-07T23:59:59.000Z

46

Mapping Heat Flux  

Science Conference Proceedings (OSTI)

An infrared camera technique designed for remote sensing of air–water heat flux has been developed. The technique uses the differential absorption of water between 3.817 and 4.514 microns. This difference causes each channel’s radiance to ...

Walt McKeown; Richard Leighton

1999-01-01T23:59:59.000Z

47

Shallow and Deep Latent Heating Modes over Tropical Oceans Observed with TRMM PR Spectral Latent Heating Data  

Science Conference Proceedings (OSTI)

Three-dimensional distributions of the apparent heat source (Q1) ? radiative heating (QR) estimated from Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) utilizing the spectral latent heating (SLH) algorithm are analyzed. Mass-...

Yukari N. Takayabu; Shoichi Shige; Wei-Kuo Tao; Nagio Hirota

2010-04-01T23:59:59.000Z

48

Influence of Land Cover and Soil Moisture on the Horizontal Distribution of Sensible and Latent Heat Fluxes in Southeast Kansas during IHOP_2002 and CASES-97  

Science Conference Proceedings (OSTI)

Analyses of daytime fair-weather aircraft and surface-flux tower data from the May–June 2002 International H2O Project (IHOP_2002) and the April–May 1997 Cooperative Atmosphere Surface Exchange Study (CASES-97) are used to document the role of ...

Margaret A. LeMone; Fei Chen; Joseph G. Alfieri; Mukul Tewari; Bart Geerts; Qun Miao; Robert L. Grossman; Richard L. Coulter

2007-02-01T23:59:59.000Z

49

An Air–Soil Layer Coupled Scheme for Computing Surface Heat Fluxes  

Science Conference Proceedings (OSTI)

An air–soil layer coupled scheme is developed to compute surface fluxes of sensible heat and latent heat from data collected at the Oklahoma Atmospheric Radiation Measurement–Cloud and Radiation Testbed (ARM–CART) stations. This new scheme ...

Qin Xu; Binbin Zhou; Stephen D. Burk; Edward H. Barker

1999-02-01T23:59:59.000Z

50

Latent Heat Thermal Energy Storage with Embedded Heat Pipes for Concentrating Solar Power Applications.  

E-Print Network (OSTI)

?? An innovative, novel concept of combining heat pipes with latent heat thermal energy storage (LHTES) for concentrating solar power (CSP) applications is explored. The… (more)

Robak, Christopher

2012-01-01T23:59:59.000Z

51

Physical model for the latent heat of fusion  

E-Print Network (OSTI)

The atomic movement induced on melting has to overcome a viscous drag resistance. It is suggested that the latent heat of fusion supplies the required energy for this physical process. The viscosity model introduced here allows computation of the latent heat from viscosity, molar volume, melting temperature, and atomic mass and diameter. The correlation between these parameters and the latent heat of 14 elements with body and face centered cubic structures was exceptional, with the correlation coefficients of 0.97 and 0.95 respectively.

Jozsef Garai

2004-07-15T23:59:59.000Z

52

Photovoltaic roof heat flux  

E-Print Network (OSTI)

and could the heat transfer processes be modeled to estimateindicating that the heat transfer processes were modeled w i

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

53

ARM - Measurement - Sensible heat flux  

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

govMeasurementsSensible heat flux govMeasurementsSensible heat flux ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Sensible heat flux The time rate of flow for the energy transferred from a warm or hot surface to whatever is touching it, typically air. Categories Surface Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments CO2FLX : Carbon Dioxide Flux Measurement Systems ECOR : Eddy Correlation Flux Measurement System EBBR : Energy Balance Bowen Ratio Station

54

ARM - Measurement - Soil heat flux  

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

heat flux heat flux ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Soil heat flux A quantity measured according to the formula B = {lambda}(dT/dz), where {lambda} is the conductivity of the soil that the heat is moving through. Categories Surface Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments CO2FLX : Carbon Dioxide Flux Measurement Systems EBBR : Energy Balance Bowen Ratio Station SEBS : Surface Energy Balance System External Instruments

55

Estimation of Surface Heat Flux  

Science Conference Proceedings (OSTI)

The authors reconsider the problem of estimating the sensible heat transfer at the earth's surface from direct measurements of turbulent fluxes in the atmospheric boundary layer. For simplicity, only horizontally homogeneous conditions are ...

Jielun Sun; Steven K. Esbensen; L. Mahrt

1995-09-01T23:59:59.000Z

56

Observational Evidence for the Influence of Surface Heat Fluxes on Rapid Maritime Cyclogenesis  

Science Conference Proceedings (OSTI)

We present an observational study of the possible effects of sea surface fluxes of latent and sensible heat on rapidly deepening cyclones over the western Atlantic Ocean. Based on the recognition that conventional operational models (specifically ...

Christopher A. Davis; Kerry A. Emanuel

1988-12-01T23:59:59.000Z

57

A Variational Method for Computing Surface Heat Fluxes from ARM Surface Energy and Radiation Balance Systems  

Science Conference Proceedings (OSTI)

A variational method is developed to compute surface fluxes of sensible and latent heat from observed wind, temperature, humidity, and surface energy and radiation budget by the surface energy and radiation balance systems (SERBS). In comparison ...

Qin Xu; Chong-Jian Qiu

1997-01-01T23:59:59.000Z

58

Technical Sessions Measurements of Surface Heat Flux Over Contrasting Surfaces  

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

Measurements of Surface Heat Flux Measurements of Surface Heat Flux Over Contrasting Surfaces R. L. Coulter J. D. Shannon T. J. Martin Argonne National Laboratory Argonne, IL 60439 In a multilaboratory field study held near Boardman in northeastern Oregon in June 1991 and described in greater detail elsewhere (Doran et al. 1991), various properties of the surface and lower atmospheric boundary layer over heavily irrigated cropland and adjacent desert steppe were investigated. The locale was selected because its disparate characteristics over various spatial scales stress the ability of general circulation models (GCMs) to describe lower boundary conditions, particularly across the discontinuity between desert (in which turbulent flux of heat must be primarily as sensible heat) and large irrigated tracts (in which turbulent flux of latent heat should be the larger term).

59

Design and simulation of latent heat storage units  

DOE Green Energy (OSTI)

This report presents the results of two years of research and development on passive latent heat storage systems. Analytical models have been developed and extended, and a computer code for simulating the performance of a latent heat storage has been developed. The code is intended to be merged into a larger solar energy system simulation code and used for making realistic system studies. Simulation studies using a code which has a flexible and accurate routine for handling the storage subsystem should lead to the development of better systems than those in which storage is added on after the rest of the system has already been selected and optimized.

Shamsundar, N.; Stein, E.; Rooz, E.; Bascaran, E.; Lee, T.C. (Houston Univ., TX (United States))

1992-04-01T23:59:59.000Z

60

Design and simulation of latent heat storage units. Final report  

DOE Green Energy (OSTI)

This report presents the results of two years of research and development on passive latent heat storage systems. Analytical models have been developed and extended, and a computer code for simulating the performance of a latent heat storage has been developed. The code is intended to be merged into a larger solar energy system simulation code and used for making realistic system studies. Simulation studies using a code which has a flexible and accurate routine for handling the storage subsystem should lead to the development of better systems than those in which storage is added on after the rest of the system has already been selected and optimized.

Shamsundar, N.; Stein, E.; Rooz, E.; Bascaran, E.; Lee, T.C. [Houston Univ., TX (United States)

1992-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Bulk Formulation of the Heat and Water Vapor Fluxes at the Air–Sea Interface, Including Nonmolecular Contributions  

Science Conference Proceedings (OSTI)

Accurate prediction of the air–sea sensible and latent heat fluxes is vital for nearly all applications of atmosphere and ocean models. Existing theories of heat transfer over rough surfaces provide a starting point, but they seem incomplete ...

James A. Mueller; Fabrice Veron

2010-01-01T23:59:59.000Z

62

Experimental Research on Solar Assisted Heat Pump Heating System with Latent Heat Storage  

E-Print Network (OSTI)

Based on the status quo that conventional energy sources are more and more reduced and environmental pollution is increasingly serious, this paper presents a new model system of conserving energy and environmental protection, namely, a Solar Assisted Heat Pump Heating System with Latent Heat Storage. In this system, solar energy is the major heat source for a heat pump, and the supplementary heat source is soil. The disagreement in time between the space heat load and heat collected by solar heat collector is solved by latent heat storage. In order to obtain such system running conditions and effects in different heating periods, an experiment has been carried out during the whole heating period in Harbin, China. The experimental results show that this system is much better for heating in initial and late periods than that in middle periods. The average heating coefficient is 6.13 for heating in initial and late periods and 2.94 for heating in middle periods. At the same time, this paper also predicts system running properties in other regions.

Han, Z.; Zheng, M.; Liu, W.; Wang, F.

2006-01-01T23:59:59.000Z

63

Sensible Heat Flux Estimated from Routine Meteorological Data by the Resistance Method  

Science Conference Proceedings (OSTI)

A method is described for evaluation of hourly values of the sensible heat flux from routine meteorological data. Use is made of the energy balance at the surface and of the Monteith-Penman formula for estimation of the latent heat flux. The soil ...

R. Berkowicz; L. P. Prahm

1982-12-01T23:59:59.000Z

64

Heat flux solarimeter  

SciTech Connect

The solarimeter presented in this work is easy to assemble. It is calibrated and its performance is validated by means of Hottel's method. Finally, the curves obtained with this solarimeter are compared to the ones obtained with a commercial solarimeter. This device is based on the evaluation of the heat flow in a metal rod. In consequence, measurements are not affected by ambient temperature variations. On the other hand, there is a linear relationship between the temperatures measured at the rod ends and the incident radiation, as can be concluded both from the theory of its operation and the calibration lines obtained. The results obtained from the global irradiance measurements in the area of Los Polvorines (Buenos Aires Province), together with a preliminary evaluation of the solarimeter's response time, are presented in this work. (author)

Sartarelli, A.; Vera, S.; Cyrulies, E. [Instituto de Desarrollo Humano, Univ. Nac. de Gral. Sarmiento (IDH, UNGS), Los Polvorines (Argentina); Echarri, R. [Instituto de Desarrollo Humano, Univ. Nac. de Gral. Sarmiento (IDH, UNGS), Los Polvorines (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Samson, I. [INTEC (Instituto Tecnologico Santo Domingo), Santo Domingo (Dominican Republic)

2010-12-15T23:59:59.000Z

65

Atmospheric Latent Heating Distributions in the Tropics Derived from Satellite Passive Microwave Radiometer Measurements  

Science Conference Proceedings (OSTI)

A method for the remote sensing of three-dimensional latent heating distributions in precipitating tropical weather systems from satellite passive microwave observations is presented. In this method, cloud model simulated hydrometeor/latent ...

William S. Olson; Christian D. Kummerow; Ye Hong; Wei-Kuo Tao

1999-06-01T23:59:59.000Z

66

Estimating Regional Surface Heat and Moisture Fluxes above Prairie Cropland from Surface and Upper-Air Measurements  

Science Conference Proceedings (OSTI)

Upper-air budget methods can be used to estimate the surface sensible and latent heat flux densities on a regional scale. This study assesses the application of radiosonde-based budget methods above homogeneous cropland. Serial daytime soundings ...

Alan G. Barr; G. S. Strong

1996-10-01T23:59:59.000Z

67

Objectively Analyzed Air–Sea Heat Fluxes for the Global Ice-Free Oceans (1981–2005)  

Science Conference Proceedings (OSTI)

A 25-yr (1981–2005) time series of daily latent and sensible heat fluxes over the global ice-free oceans has been produced by synthesizing surface meteorology obtained from satellite remote sensing and atmospheric model reanalyses outputs. The ...

Lisan Yu; Robert A. Weller

2007-04-01T23:59:59.000Z

68

U.S. West Coast Surface Heat Fluxes, Wind Stress, and Wind Stress Curl from a Mesoscale Model  

Science Conference Proceedings (OSTI)

Monthly averages of numerical model fields are beneficial for depicting patterns in surface forcing such as sensible and latent heat fluxes, wind stress, and wind stress curl over data-sparse ocean regions. Grid resolutions less than 10 km ...

T. Haack; S. D. Burk; R. M. Hodur

2005-11-01T23:59:59.000Z

69

ARM Energy Balance Bowen Ratio (EBBR) station: surf. heat flux and related data, 30-min  

DOE Data Explorer (OSTI)

The Energy Balance Bowen Ratio (EBBR) system produces 30-min estimates of the vertical fluxes of sensible and latent heat at the local surface. Flux estimates are calculated from observations of net radiation, soil surface heat flux, and the vertical gradients of temperature and relative humidity. Meteorological data collected by the EBBR are used to calculate bulk aerodynamic fluxes, which are used in the Bulk Aerodynamic Technique (BA) EBBR value-added product (VAP) to replace sunrise and sunset spikes in the flux data. A unique aspect of the system is the automatic exchange mechanism (AEM), which helps to reduce errors from instrument offset drift.

Cook, David

70

ARM Energy Balance Bowen Ratio (EBBR) station: surf. heat flux and related data, 30-min  

SciTech Connect

The Energy Balance Bowen Ratio (EBBR) system produces 30-min estimates of the vertical fluxes of sensible and latent heat at the local surface. Flux estimates are calculated from observations of net radiation, soil surface heat flux, and the vertical gradients of temperature and relative humidity. Meteorological data collected by the EBBR are used to calculate bulk aerodynamic fluxes, which are used in the Bulk Aerodynamic Technique (BA) EBBR value-added product (VAP) to replace sunrise and sunset spikes in the flux data. A unique aspect of the system is the automatic exchange mechanism (AEM), which helps to reduce errors from instrument offset drift.

Cook, David

1993-07-04T23:59:59.000Z

71

Spectral Retrieval of Latent Heating Profiles from TRMM PR Data. Part I: Development of a Model-Based Algorithm  

Science Conference Proceedings (OSTI)

An algorithm, the spectral latent heating (SLH) algorithm, has been developed to estimate latent heating profiles for the Tropical Rainfall Measuring Mission precipitation radar with a cloud-resolving model (CRM). Heating-profile lookup tables ...

Shoichi Shige; Yukari N. Takayabu; Wei-Kuo Tao; Daniel E. Johnson

2004-08-01T23:59:59.000Z

72

Boundary layer structure over areas of heterogeneous heat fluxes  

SciTech Connect

In general circulation models (GCMs), some properties of a grid element are necessarily considered homogeneous. That is, for each grid volume there is associated a particular combination of boundary layer depth, vertical profiles of wind and temperature, surface fluxes of sensible and latent heat, etc. In reality, all of these quantities may exhibit significant spatial variations within the grid area, and the larger the area the greater the likely variations. In balancing the benefits of higher resolution against increased computational time and expense, it is useful to consider what the consequences of such subgrid-scale variability may be. Moveover, in interpreting the results of a simulation, one must be able to define an appropriate average value over a grid. There are two aspects of this latter problem: (1) in observations, how does one take a set of discrete or volume-averaged measurements and relate these to properties of the entire domain, and (2) in computations, how can subgrid-scale features be accounted for in the model parameterizations To address these and related issues, two field campaigns were carried out near Boardman, Oregon, in June 1991 and 1992. These campaigns were designed to measure the surface fluxes of latent and sensible heat over adjacent areas with strongly contrasting surface types and to measure the response of the boundary layer to those fluxes. This paper discuses some initial findings from those campaigns.

Doran, J.C. (Pacific Northwest Lab., Richland, WA (United States)); Barnes, F.J. (Los Alamos National Lab., NM (United States)); Coulter, R.L. (Argonne National Lab., IL (United States)); Crawford, T.L. (National Oceanic and Atmospheric Administration, Oak Ridge, TN (United States). Air Resources Lab. Atmospheric Turbulence and Diffusion Div.)

1993-01-01T23:59:59.000Z

73

Boundary layer structure over areas of heterogeneous heat fluxes  

SciTech Connect

In general circulation models (GCMs), some properties of a grid element are necessarily considered homogeneous. That is, for each grid volume there is associated a particular combination of boundary layer depth, vertical profiles of wind and temperature, surface fluxes of sensible and latent heat, etc. In reality, all of these quantities may exhibit significant spatial variations the grid area, and the larger the area the greater the likely variations. In balancing the benefits of higher resolution against increased computational time and expense, it is useful to consider what the consequences of such subgrid-scale variability may be. Moreover, in interpreting the results of a simulation, one must be able to define an appropriate average value over a grid. There are two aspects of this latter problem: (1) in observations, how does one take a set of discrete or volume-averaged measurements and relate these to properties of the entire domain, and (2) in computations, how can subgrid-scale features be accounted for in the model parameterizations? To address these and related issues, two field campaigns were carried out near Boardman, Oregon, in June 1991 and 1992. These campaigns were designed to measure the surface fluxes of latent and sensible heat over adjacent areas with strongly contrasting surface types and to measure the response of the boundary layer to those fluxes. This paper discusses some initial findings from those campaigns.

Doran, J.C. [Pacific Northwest Lab., Richland, WA (United States); Barnes, F.J. [Los Alamos National Lab., NM (United States); Coulter, R.L. [Argonne National Lab., IL (United States); Crawford, T.L. [National Oceanic and Atmospheric Administration, Oak Ridge, TN (United States). Air Resources Lab. Atmospheric Turbulence and Diffusion Div.

1993-01-01T23:59:59.000Z

74

Boundary layer structure over areas of heterogeneous heat fluxes  

SciTech Connect

In general circulation models (GCMs), some properties of a grid element are necessarily considered homogeneous. That is, for each grid volume there is associated a particular combination of boundary layer depth, vertical profiles of wind and temperature, surface fluxes of sensible and latent heat, etc. In reality, all of these quantities may exhibit significant spatial variations within the grid area, and the larger the area the greater the likely variations. In balancing the benefits of higher resolution against increased computational time and expense, it is useful to consider what the consequences of such subgrid-scale variability may be. Moveover, in interpreting the results of a simulation, one must be able to define an appropriate average value over a grid. There are two aspects of this latter problem: (1) in observations, how does one take a set of discrete or volume-averaged measurements and relate these to properties of the entire domain, and (2) in computations, how can subgrid-scale features be accounted for in the model parameterizations? To address these and related issues, two field campaigns were carried out near Boardman, Oregon, in June 1991 and 1992. These campaigns were designed to measure the surface fluxes of latent and sensible heat over adjacent areas with strongly contrasting surface types and to measure the response of the boundary layer to those fluxes. This paper discuses some initial findings from those campaigns.

Doran, J.C. [Pacific Northwest Lab., Richland, WA (United States); Barnes, F.J. [Los Alamos National Lab., NM (United States); Coulter, R.L. [Argonne National Lab., IL (United States); Crawford, T.L. [National Oceanic and Atmospheric Administration, Oak Ridge, TN (United States). Air Resources Lab. Atmospheric Turbulence and Diffusion Div.

1993-04-01T23:59:59.000Z

75

Boundary layer structure over areas of heterogeneous heat fluxes  

SciTech Connect

In general circulation models (GCMs), some properties of a grid element are necessarily considered homogeneous. That is, for each grid volume there is associated a particular combination of boundary layer depth, vertical profiles of wind and temperature, surface fluxes of sensible and latent heat, etc. In reality, all of these quantities may exhibit significant spatial variations the grid area, and the larger the area the greater the likely variations. In balancing the benefits of higher resolution against increased computational time and expense, it is useful to consider what the consequences of such subgrid-scale variability may be. Moreover, in interpreting the results of a simulation, one must be able to define an appropriate average value over a grid. There are two aspects of this latter problem: (1) in observations, how does one take a set of discrete or volume-averaged measurements and relate these to properties of the entire domain, and (2) in computations, how can subgrid-scale features be accounted for in the model parameterizations To address these and related issues, two field campaigns were carried out near Boardman, Oregon, in June 1991 and 1992. These campaigns were designed to measure the surface fluxes of latent and sensible heat over adjacent areas with strongly contrasting surface types and to measure the response of the boundary layer to those fluxes. This paper discusses some initial findings from those campaigns.

Doran, J.C. (Pacific Northwest Lab., Richland, WA (United States)); Barnes, F.J. (Los Alamos National Lab., NM (United States)); Coulter, R.L. (Argonne National Lab., IL (United States)); Crawford, T.L. (National Oceanic and Atmospheric Administration, Oak Ridge, TN (United States). Air Resources Lab. Atmospheric Turbulence and Diffusion Div.)

1993-01-01T23:59:59.000Z

76

The Effect of Latent Heat Release on the Evolution of a Warm Occluded Thermal Structure  

Science Conference Proceedings (OSTI)

The effect of latent heat release on the development of the occluded thermal structure in a major winter storm is examined through comparison of full physics (FP) and no-latent-heat-release (NLHR) simulations of the event performed using the ...

Derek J. Posselt; Jonathan E. Martin

2004-02-01T23:59:59.000Z

77

The Importance of Resolving Mesoscale Latent Heating in the North Atlantic Storm Track  

Science Conference Proceedings (OSTI)

Theoretical, observational, and modeling studies have established an important role for latent heating in midlatitude cyclone development. Models simulate some contribution from condensational heating to cyclogenesis, even with relatively coarse ...

Jeff Willison; Walter A. Robinson; Gary M. Lackmann

2013-07-01T23:59:59.000Z

78

Equatorial Waves in the Upper Troposphere and Lower Stratosphere Forced by Latent Heating Estimated from TRMM Rain Rates  

Science Conference Proceedings (OSTI)

Equatorial atmospheric waves in the upper troposphere and lower stratosphere (UTLS), excited by latent heating, are investigated by using a global spectral model. The latent heating profiles are derived from the 3-hourly Tropical Rainfall ...

Jung-Hee Ryu; M. Joan Alexander; David A. Ortland

2011-10-01T23:59:59.000Z

79

Comparison of the high temperature heat flux sensor to traditional heat flux gages under high heat flux conditions.  

SciTech Connect

Four types of heat flux gages (Gardon, Schmidt-Boelter, Directional Flame Temperature, and High Temperature Heat Flux Sensor) were assessed and compared under flux conditions ranging between 100-1000 kW/m2, such as those seen in hydrocarbon fire or propellant fire conditions. Short duration step and pulse boundary conditions were imposed using a six-panel cylindrical array of high-temperature tungsten lamps. Overall, agreement between all gages was acceptable for the pulse tests and also for the step tests. However, repeated tests with the HTHFS with relatively long durations at temperatures approaching 1000%C2%B0C showed a substantial decrease (10-25%) in heat flux subsequent to the initial test, likely due to the mounting technique. New HTHFS gages have been ordered to allow additional tests to determine the cause of the flux reduction.

Blanchat, Thomas K.; Hanks, Charles R.

2013-04-01T23:59:59.000Z

80

Critical heat flux test apparatus  

DOE Patents (OSTI)

An apparatus for testing, in situ, highly irradiated specimens at high temperature transients is provided. A specimen, which has a thermocouple device attached thereto, is manipulated into test position in a sealed quartz heating tube by a robot. An induction coil around a heating portion of the tube is powered by a radio frequency generator to heat the specimen. Sensors are connected to monitor the temperatures of the specimen and the induction coil. A quench chamber is located below the heating portion to permit rapid cooling of the specimen which is moved into this quench chamber once it is heated to a critical temperature. A vacuum pump is connected to the apparatus to collect any released fission gases which are analyzed at a remote location.

Welsh, R.E.; Doman, M.J.; Wilson, E.C.

1990-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Critical heat flux test apparatus  

DOE Patents (OSTI)

An apparatus for testing, in situ, highly irradiated specimens at high temperature transients is provided. A specimen, which has a thermocouple device attached thereto, is manipulated into test position in a sealed quartz heating tube by a robot. An induction coil around a heating portion of the tube is powered by a radio frequency generator to heat the specimen. Sensors are connected to monitor the temperatures of the specimen and the induction coil. A quench chamber is located below the heating portion to permit rapid cooling of the specimen which is moved into this quench chamber once it is heated to a critical temperature. A vacuum pump is connected to the apparatus to collect any released fission gases which are analyzed at a remote location.

Welsh, R.E.; Doman, M.J.; Wilson, E.C.

1990-12-31T23:59:59.000Z

82

Estimation of Global Ground Heat Flux  

Science Conference Proceedings (OSTI)

This study investigates the use of a previously published algorithm for estimating ground heat flux (GHF) at the global scale. The method is based on an analytical solution of the diffusion equation for heat transfer in a soil layer and has been ...

William B. Bennett; Jingfeng Wang; Rafael L. Bras

2008-08-01T23:59:59.000Z

83

The effect of nonuniform axial heat flux distribution on the critical heat flux  

E-Print Network (OSTI)

A systematic experimental and analytic investigation of the effect of nonuniform axial heat flux distribution on critical heat rilux was performed with water in the quality condition. Utilizing a model which ascribes the ...

Todreas, Neil E.

1965-01-01T23:59:59.000Z

84

Spatial and temporal distribution of latent heating in the South Asian monsoon region.  

E-Print Network (OSTI)

??Information from the TRMM-CSH and TRMM-2A12 datasets is used to examine the four-dimensional latent heating (LH) structures over the Asian monsoon region between 1998 and… (more)

Zuluaga-Arias, Manuel D.

2009-01-01T23:59:59.000Z

85

Latent Heat Release in an Extratropical Cyclone that Developed Explosively over the Southeastern United States  

Science Conference Proceedings (OSTI)

Using the Goddard Laboratory for Atmospheres FGGE Level III-b analyses, the latent heat release (LHR) associated with an extratropical cyclone that deepened explosively over the southeastern United States is investigated. Parameterized LUR was ...

Earl K. Fosdick; Phillip J. Smith

1991-01-01T23:59:59.000Z

86

Precipitation and Latent Heating Characteristics of the Major Tropical Western Pacific Cloud Regimes  

Science Conference Proceedings (OSTI)

An objective tropical cloud regime classification based on daytime averaged cloud-top pressure and optical thickness information from the International Satellite Cloud Climatology Project (ISCCP) is combined with precipitation and latent heating ...

Christian Jakob; Courtney Schumacher

2008-09-01T23:59:59.000Z

87

Four-Dimensional Structure of Monthly Latent Heating Derived from SSM/ISatellite Measurements  

Science Conference Proceedings (OSTI)

Time–space distributions of mean monthly latent heating estimated from Special Sensor Microwave/Imager (SSM/I) passive microwave satellite measurements using the Florida State University precipitation profile retrieval algorithm over ocean ...

Song Yang; Eric A. Smith

1999-04-01T23:59:59.000Z

88

Latent Heating and Mixing Due to Entrainment in Tropical Deep Convection  

Science Conference Proceedings (OSTI)

Recent studies have noted the role of latent heating above the freezing level in reconciling Riehl and Malkus’ Hot Tower Hypothesis (HTH) with evidence of diluted tropical deep convective cores. This study evaluates recent modifications to the HTH ...

Clayton J. McGee; Susan C. van den Heever

89

Non-Quasi-Geostrophic Effects in Baroclinic Waves with Latent Heat Release  

Science Conference Proceedings (OSTI)

A second-order theory of baroclinic waves is developed to investigate non-quasi-geostrophic behavior in disturbances in which latent heat release associated with condensation is permitted to occur in an atmosphere saturated with water vapor. A ...

Chung-Muh Tang; George H. Fichtl

1984-05-01T23:59:59.000Z

90

Direct and Indirect Effects of Latent Heat Release on a Synoptic-Scale Wave System  

Science Conference Proceedings (OSTI)

The primary goal of this paper is to diagnose, the “direct” and “indirect” effects of latent heat release on a synoptic-scale wave system containing an extratropical cyclone that developed over the eastern United States. To achieve this goal, ...

Patricia M. Pauley; Phillip J. Smith

1988-05-01T23:59:59.000Z

91

Latent Heat Release as a Possible Forcing Mechanism for Atmospheric Tides  

Science Conference Proceedings (OSTI)

The consequences of the hypothesis of Lindzen (1978) that latent heat release may be a significant excitation mechanism for the semidiurnal atmospheric tide are examined in some detail. Harmonic analysis of hourly rainfall data from 79 tropical ...

Kevin Hamilton

1981-01-01T23:59:59.000Z

92

The Role of Latent Heat Release in Baroclinic Waves-Without ?-Effect  

Science Conference Proceedings (OSTI)

In this paper we develop the analytical theory of two-level quasi-geostrophic baroclinic waves without ?-effect aimed at understanding the role of latent heat release on the development of baroclinic waves.

Chung-Muh Tang; George H. Fichtl

1983-01-01T23:59:59.000Z

93

Indirectly heated fluidized bed biomass gasification using a latent heat ballast  

DOE Green Energy (OSTI)

The objective of this study is to improve the heating value of gas produced during gasification of biomass fuels using an indirectly heated gasifier based on latent heat ballasting. The latent heat ballast consists of lithium fluoride salt encased in tubes suspended in the reactor. The lithium fluoride has a melting point that is near the desired gasification temperature. With the ballast a single reactor operating in a cyclic mode stores energy during a combustion phase and releases it during a pyrolysis phase. Tests were carried out in a fluidized bed reactor to evaluate the concept. The time to cool the reactor during the pyrolysis phase from 1,172 K (1,650 F) to 922 K (1,200 F) increased 102% by use of the ballast system. This extended pyrolysis time allowed 33% more biomass to be gasified during a cycle. Additionally, the total fuel fraction pyrolyzed to produce useful gas increased from 74--80%. Higher heating values of 14.2 to 16.6 MJ/Nm{sup 3} (382--445 Btu/scf) on a dry basis were obtained from the ballasted gasifier.

Pletka, R.; Brown, R.; Smeenk, J. [Iowa State Univ., Ames, IA (United States). Center for Coal and the Environment

1998-12-31T23:59:59.000Z

94

Heat Transfer and Latent Heat Storage in Inorganic Molten Salts for Concentrating Solar Power Plants  

Science Conference Proceedings (OSTI)

A key technological issue facing the success of future Concentrating Solar Thermal Power (CSP) plants is creating an economical Thermal Energy Storage (TES) system. Current TES systems use either sensible heat in fluids such as oil, or molten salts, or use thermal stratification in a dual-media consisting of a solid and a heat-transfer fluid. However, utilizing the heat of fusion in inorganic molten salt mixtures in addition to sensible heat , as in a Phase change material (PCM)-based TES, can significantly increase the energy density of storage requiring less salt and smaller containers. A major issue that is preventing the commercial use of PCM-based TES is that it is difficult to discharge the latent heat stored in the PCM melt. This is because when heat is extracted, the melt solidifies onto the heat exchanger surface decreasing the heat transfer. Even a few millimeters of thickness of solid material on heat transfer surface results in a large drop in heat transfer due to the low thermal conductivity of solid PCM. Thus, to maintain the desired heat rate, the heat exchange area must be large which increases cost. This project demonstrated that the heat transfer coefficient can be increase ten-fold by using forced convection by pumping a hyper-eutectic salt mixture over specially coated heat exchanger tubes. However,only 15% of the latent heat is used against a goal of 40% resulting in a projected cost savings of only 17% against a goal of 30%. Based on the failure mode effect analysis and experience with pumping salt at near freezing point significant care must be used during operation which can increase the operating costs. Therefore, we conclude the savings are marginal to justify using this concept for PCM-TES over a two-tank TES. The report documents the specialty coatings, the composition and morphology of hypereutectic salt mixtures and the results from the experiment conducted with the active heat exchanger along with the lessons learnt during experimentation.

Mathur, Anoop [Terrafore Inc.] [Terrafore Inc.

2013-08-14T23:59:59.000Z

95

Effects of urban land cover modifications in a mesoscale meteorological model on surface temperature and heat fluxes in the Phoenix metropolitan area.  

E-Print Network (OSTI)

and latent heat fluxes and therefore the ground temperature, Tg. Evaporation, E, for each grid cell temperature and heat fluxes in the Phoenix metropolitan area. S. Grossman-Clarke1, J.A. Zehnder2, and W) satellite images [2]. The data were upscaled to a 30-second grid and used to augment and correct

Hall, Sharon J.

96

Latent heat fluxes through nano-engineered porous materials  

E-Print Network (OSTI)

Micro- and nano-scale truss architectures provide mechanical strength, light weight, and breatheability in polymer barriers. Liquid evaporation and transport of resulting vapor through truss voids (pores) cools surfaces ...

Traum, Matthew J. (Matthew Jason), 1977-

2007-01-01T23:59:59.000Z

97

Radar-Derived Estimates of Latent Heating in the Subtropics  

Science Conference Proceedings (OSTI)

Atmospheric warming from cloud heating has a major affect on worldwide atmospheric circulations and climate. Studies have shown that the dominant source for cloud heating is the phase change of water. The location and magnitude of cloud heating ...

Tina J. Cartwright; Peter S. Ray

1999-05-01T23:59:59.000Z

98

On the Use of Lower Saturation Criteria for Release of Latent Heat in NWP Models  

Science Conference Proceedings (OSTI)

In several numerical models the large-scale release of latent heat is evaluated when the mixing ratio q exceeds a certain fraction (SATRH < 1) of its saturation value qs. The predicted mixing ratio at the end of a time step in the above case is ...

Mukut B. Mathur

1983-09-01T23:59:59.000Z

99

The Role of Latent Heat Release in the Evolution of a Weak Extratropical Cyclone  

Science Conference Proceedings (OSTI)

A study of the sensitivity of a weak winter extratropical cyclone to latent heat release (LHR) is presented using 48-h simulations of the cyclone's evolution derived from three versions of the LFM model: a MOIST simulation in which full model ...

John E. Zimmerman; Phillip J. Smith; David R. Smith

1989-05-01T23:59:59.000Z

100

Environmental Forcing of Supertyphoon Paka’s (1997) Latent Heat Structure  

Science Conference Proceedings (OSTI)

The distribution and intensity of total (i.e., combined stratified and convective processes) rain rate/latent heat release (LHR) were derived for Tropical Cyclone Paka during the period 9–21 December 1997 from the F-10, F-11, F-13, and F-14 ...

Edward Rodgers; William Olson; Jeff Halverson; Joanne Simpson; Harold Pierce

2000-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

A Latent-and Sensible-Heat Polynya Model for the North Water, Northern Baffin Bay  

Science Conference Proceedings (OSTI)

The Pease latent-heat polynya model is coupled to a reduced-gravity, coastal upwelling model in order to simulate the formation and maintenance of the North Water (NOW), the Arctic's largest polynya, located in northern Beffin Bay. In this region,...

Lawrence A. Mysak; Fengting Huang

1992-06-01T23:59:59.000Z

102

Latent Heating and Cooling Rates in Developing and Nondeveloping Tropical Disturbances during TCS-08: Radar-Equivalent Retrievals from Mesoscale Numerical Models and ELDORA  

Science Conference Proceedings (OSTI)

Latent heating and cooling rates have a critical role in predicting tropical cyclone formation and intensification. In a prior study, Park and Elsberry estimated the latent heating and cooling rates from aircraft Doppler radar [Electra Doppler ...

Myung-Sook Park; Andrew B. Penny; Russell L. Elsberry; Brian J. Billings; James D. Doyle

2013-01-01T23:59:59.000Z

103

Spectral Retrieval of Latent Heating Profiles from TRMM PR Data. Part IV: Comparisons of Lookup Tables from Two- and Three-Dimensional Cloud-Resolving Model Simulations  

Science Conference Proceedings (OSTI)

The spectral latent heating (SLH) algorithm was developed to estimate latent heating profiles for the Tropical Rainfall Measuring Mission Precipitation Radar (TRMM PR). The method uses TRMM PR information (precipitation-top height, precipitation ...

Shoichi Shige; Yukari N. Takayabu; Satoshi Kida; Wei-Kuo Tao; Xiping Zeng; Chie Yokoyama; Tristan L’Ecuyer

2009-10-01T23:59:59.000Z

104

Spatial Variation in Turbulent Heat Fluxes in Drake Passage  

Science Conference Proceedings (OSTI)

High-resolution underway shipboard atmospheric and oceanic observations collected in Drake Passage from 2000 to 2009 are used to examine the spatial scales of turbulent heat fluxes and flux-related state variables. The magnitude of the seasonal ...

ChuanLi Jiang; Sarah T. Gille; Janet Sprintall; Kei Yoshimura; Masao Kanamitsu

2012-03-01T23:59:59.000Z

105

High heat flux engineering in solar energy applications  

DOE Green Energy (OSTI)

Solar thermal energy systems can produce heat fluxes in excess of 10,000 kW/m{sup 2}. This paper provides an introduction to the solar concentrators that produce high heat flux, the receivers that convert the flux into usable thermal energy, and the instrumentation systems used to measure flux in the solar environment. References are incorporated to direct the reader to detailed technical information.

Cameron, C.P.

1993-07-01T23:59:59.000Z

106

Stability-Dependent Exchange Coefficients for Air–Sea Fluxes  

Science Conference Proceedings (OSTI)

This study introduces exchange coefficients for wind stress (CD), latent heat flux (CL), and sensible heat flux (CS) over the global ocean. They are obtained from the state-of-the-art Coupled Ocean–Atmosphere Response Experiment (COARE) bulk ...

A. Birol Kara; Harley E. Hurlburt; Alan J. Wallcraft

2005-07-01T23:59:59.000Z

107

Designing, testing, and analyzing coupled, flux transformer heat.  

E-Print Network (OSTI)

??The proposed research involves designing, testing, and ics. analyzing a coupled, flux transformer heat pipe system following the patent of Oktay and Peterson (1997). Experiments… (more)

Renzi, Kimberly Irene

2012-01-01T23:59:59.000Z

108

On Heat Flux Boundary Conditions for Ocean Models  

Science Conference Proceedings (OSTI)

Recent modeling studies of thermohaline variability have imposed rapid damping of modeled sea surface temperature (SST) anomalies equivalent to assuming the atmosphere has an infinite heat capacity. Such surface heat flux parameterizations ...

Richard Seager; Yochanan Kushnir; Mark A. Cane

1995-12-01T23:59:59.000Z

109

Estimation of Latent Heating of Rainfall during the Onset of the Indian Monsoon Using TRMM PR and Radiosonde Data  

Science Conference Proceedings (OSTI)

The objective of this study is to estimate the vertical structure of the latent heating of precipitation in the vicinity of the Himalayas. Based on a cloud physics parameterization and the thermodynamic equilibrium equation, a simple algorithm is ...

Ramata Magagi; Ana P. Barros

2004-02-01T23:59:59.000Z

110

Entropy Budget of an Atmosphere in Radiative–Convective Equilibrium. Part II: Latent Heat Transport and Moist Processes  

Science Conference Proceedings (OSTI)

In moist convection, atmospheric motions transport water vapor from the earth's surface to the regions where condensation occurs. This transport is associated with three other aspects of convection: the latent heat transport, the expansion work ...

Olivier Pauluis; Isaac M. Held

2002-01-01T23:59:59.000Z

111

Latent Heating and Cooling Rates in Developing and Nondeveloping Tropical Disturbances during TCS-08: TRMM PR versus ELDORA Retrievals  

Science Conference Proceedings (OSTI)

Unique sets of Electra Doppler Radar (ELDORA) observations in both developing and nondeveloping tropical disturbances in the western North Pacific are used to retrieve latent heating and cooling rates. During the reintensification of Sinlaku, ...

Myung-Sook Park; Russell L. Elsberry

2013-01-01T23:59:59.000Z

112

Assessment of Latent Heat Reservoirs for Thermal Management of QCW Laser Diodes  

SciTech Connect

There is great interest in improving the thermal management of laser diodes intended for use as pumps in inertial confinement fusion systems. Laser diode power is currently constrained by heat dissipation in the diodes. Diodes typically dissipate a quantity of heat that is comparable to their optical power output. This heating of the diode junction causes a thermal rollover that prevents the output power from scaling linearly with current drive, and also results in reliability limits due to catastrophic failure at diode mirror facets. For the pulsed, quasi-continuous wave (QCW) operating mode employed for LIFE and certain DOD applications, {approx}5 kW/cm{sup 2} of heat must be removed on timescales of {approx}100{micro}s, which is determined by thermal paths located within {approx}200 {micro}m of the laser junction. For these reasons, QCW thermal management is extremely challenging. Reducing the diode junction temperature enables more efficient operation, reduced thermal chirp, and operation at higher output power without compromised reliability - which improves the diode costs as measured in $/W. We have proposed the use of latent heat reservoirs to improve thermal management of diodes used in pulsed, quasi-continuous wave (QCW) operation. Our basic concept involves placement of a reservoir of low-melting-point metal within a few hundred microns of the laser junction, as in Fig. 1-1. This metal's latent heat of fusion maintains a nearly constant temperature (like a cold plate) in the very near vicinity of the diode junction. This cold reservoir creates large thermal gradients, which in turn are anticipated to drive a large heat flow from the diode. In contrast, conventional QCW devices rely on thermal diffusion into a large solid mass which cannot be held at a fixed temperature, which significantly limits the thermal extraction. Our operational concept involves phase changes within the reservoir during every QCW pulse. During the early portion of the pulse, heating of the diode and its surrounding material initiates melting within the latent heat reservoir. This phase change results in a near-constant reservoir temperature that facilitates heat transfer. During the long ({approx}100 ms) time between QCW pulses, the reservoir metal resolidifies. A simple back-of-the-envelope calculation based on Gallium metal shows that a 50 {micro}m thick Gallium reservoir is sufficient to absorb all heat generated by a 350 {micro}s pulse at 5 kW/cm{sup 2}. While this calculation shows that a latent heat reservoir can provide sufficient capacity to handle the magnitude of heat generated, it does not address the transient change in the diode junction temperature, which depends on details the heat flow into and through the reservoir. For this reason, we undertook a set of numerical experiments to quantitatively assess the impact of latent heat reservoirs on junction temperature. This report documents the results of these simulations.

Deri, B; Kotovsky, J; Spadaccini, C

2010-03-15T23:59:59.000Z

113

Tracking heat flux sensors for concentrating solar applications  

DOE Patents (OSTI)

Innovative tracking heat flux sensors located at or near the solar collector's focus for centering the concentrated image on a receiver assembly. With flux sensors mounted near a receiver's aperture, the flux gradient near the focus of a dish or trough collector can be used to precisely position the focused solar flux on the receiver. The heat flux sensors comprise two closely-coupled thermocouple junctions with opposing electrical polarity that are separated by a thermal resistor. This arrangement creates an electrical signal proportional to heat flux intensity, and largely independent of temperature. The sensors are thermally grounded to allow a temperature difference to develop across the thermal resistor, and are cooled by a heat sink to maintain an acceptable operating temperature.

Andraka, Charles E; Diver, Jr., Richard B

2013-06-11T23:59:59.000Z

114

Feedbacks between Eddy Heat Fluxes and Radiative Heating in an Energy-Balance Model  

Science Conference Proceedings (OSTI)

The response of midlatitude temperature structure to changes in radiative forcing is examined in an analytical energy-balance model that includes parameterized eddy heat fluxes and linear radiative heating. The characteristics of heat-...

Lee E. Branscome; Enda O'Brien

1988-02-01T23:59:59.000Z

115

Spectral Retrieval of Latent Heating Profiles from TRMM PR Data. Part II: Algorithm Improvement and Heating Estimates over Tropical Ocean Regions  

Science Conference Proceedings (OSTI)

The spectral latent heating (SLH) algorithm was developed for the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) in Part I of this study. The method uses PR information [precipitation-top height (PTH), precipitation rates at ...

Shoichi Shige; Yukari N. Takayabu; Wei-Kuo Tao; Chung-Lin Shie

2007-07-01T23:59:59.000Z

116

Transient heat flux shielding using thermal metamaterials  

E-Print Network (OSTI)

We have developed a heat shield based on a metamaterial engineering approach to shield a region from transient diffusive heat flow. The shield is designed with a multilayered structure to prescribe the appropriate spatial profile for heat capacity, density, and thermal conductivity of the effective medium. The heat shield was experimentally compared to other isotropic materials.

Narayana, Supradeep; Sato, Yuki

2013-01-01T23:59:59.000Z

117

Influences of biomass heat and biochemical energy storages on the land surface fluxes and radiative temperature  

SciTech Connect

We conducted observations and modeling at a forest site to assess importance of biomass heat and biochemical energy storages for land-atmosphere interactions. We used the terrestrial ecosystem Fluxes And Pools Integrated Simulator (FAPIS). We first examined FAPIS performance by testing its predictions with and without biomass energy storages against measurements of surface energy and CO2 fluxes. We then evaluated the magnitudes and temporal patterns of the calculated biomass energy storages. Effects of energy storages on flux exchanges and variations of radiative temperature were investigated by contrasting FAPIS simulations with and without the storages. We found that with the storages, FAPIS predictions agreed with measurements well; without them, FAPIS performance deteriorated for all surface energy fluxes. The biomass heat storage and biochemical energy storage had clear diurnal patterns with typical ranges from -50 to 50 and -3 to 20 Wm-2, respectively; these typical ranges were exceeded substantially when there were sudden changes in atmospheric conditions. Without-storage simulations produced larger sensible and latent heat fluxes during the day but smaller fluxes (more negative values) at night as compared with with-storage simulations. Similarly, without-storage simulations had higher surface radiative temperature during the day but lower radiative temperature at night, indicating that the biomass energy storages act to dampen diurnal temperature range. Therefore, biomass heat and biochemical energy storages are an integral and substantial part of the surface energy budget and play a role in modulating land surface temperatures and must be considered in studies of land - atmosphere interactions and climate modeling.

Gu, Lianhong [ORNL; Meyers, T. P. [NOAA ATDD; Pallardy, Stephen G. [University of Missouri; Hanson, Paul J [ORNL; Yang, Bai [ORNL; Heuer, Mark [ATDD, NOAA; Hosman, K. P. [University of Missouri; Liu, Qing [ORNL; Riggs, Jeffery S [ORNL; Sluss, Daniel Wayne [ORNL; Wullschleger, Stan D [ORNL

2007-01-01T23:59:59.000Z

118

The Skin-Layer Ocean Heat Flux Instrument (SOHFI). Part I: Design and Laboratory Characterization  

Science Conference Proceedings (OSTI)

An untended instrument to measure ocean surface heat flux has been developed for use in support of field experiments and the investigation of heat flux parameterization techniques. The sensing component of the Skin-Layer Ocean Heat Flux ...

L. A. Sromovsky; J. R. Anderson; F. A. Best; J. P. Boyle; C. A. Sisko; V. E. Suomi

1999-09-01T23:59:59.000Z

119

Estimation of Surface Radiation and Energy Flux Densities from Single-Level Weather Data  

Science Conference Proceedings (OSTI)

A scheme is proposed that relates surface flux densities of sensible heat, latent heat, and momentum to routine weather data. The scheme contains parameterizations concerning the radiation components and the surface energy flux densities. The ...

Wim C. de Rooy; A. A. M. Holtslag

1999-05-01T23:59:59.000Z

120

Convective Boundary Layers Driven by Nonstationary Surface Heat Fluxes  

Science Conference Proceedings (OSTI)

In this study the response of dry convective boundary layers to nonstationary surface heat fluxes is systematically investigated. This is relevant not only during sunset and sunrise but also, for example, when clouds modulate incoming solar ...

Robert van Driel; Harm J. J. Jonker

2011-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Eddy Heat Flux in the Subtropical North Pacific  

Science Conference Proceedings (OSTI)

Meridional eddy heat flux in the subtropical North Pacific is estimated from TRANSPAC ship-of-opportunity data collected during 1976–80. Two methods are used. The first fits simple functional forms to be temporal anomalies of the temperature ...

Andrew F. Bennett; Warren B. White

1986-04-01T23:59:59.000Z

122

Direct Estimation of Heat Flux in a Seasonal Thermocline  

Science Conference Proceedings (OSTI)

This paper reports on a direct measurement of the turbulent heat flux. The sampling was from a submarine that used a conventional airfoil probe to measure the vertical component of turbulent velocity and a thermistor probe to measure the ...

Hidekatsu Yamazaki; Thomas Osborn

1993-03-01T23:59:59.000Z

123

Direct Heat Flux Estimates Using a Towed Vehicle  

Science Conference Proceedings (OSTI)

Direct estimates of vertical heat flux were computed using data collected with a towed vehicle that carried collocated velocity and temperature sensors. Horizontal wavenumbers from about 1 to 40 cpm were resolved, which excludes some potentially ...

M. Fleury; R. G. Lueck

1994-04-01T23:59:59.000Z

124

Estimating Sensible Heat Flux from the Oklahoma Mesonet  

Science Conference Proceedings (OSTI)

The challenges of using the Oklahoma Mesonet for calculations of sensible heat flux are discussed. The mesonet is an integrated network of 115 remote and automated meteorological stations across Oklahoma that provides the spatial density to ...

Jerald A. Brotzge; Kenneth C. Crawford

2000-01-01T23:59:59.000Z

125

Surface Heat Flux Variations across the Kuroshio Extension as Observed by Surface Flux Buoys  

Science Conference Proceedings (OSTI)

Wintertime sea surface heat flux variability across the Kuroshio Extension (KE) front is analyzed using data from the Kuroshio Extension Observatory (KEO) buoy in the Kuroshio recirculation gyre south of the KE front and from the Japan Agency for ...

Masanori Konda; Hiroshi Ichikawa; Hiroyuki Tomita; Meghan F. Cronin

2010-10-01T23:59:59.000Z

126

Considerations and measurements of latent-heat-storage salts for secondary thermal battery applications  

Science Conference Proceedings (OSTI)

Given its potential benefits, the practicality of using a latent heat-storage material as the basis for a passive thermal management system is being assessed by Chloride Silent Power Ltd. (CSPL) with technical assistance from Beta Power, Inc. and Sandia National Laboratories (SNL). Based on the experience gained in large-scale solar energy storage programs, fused salts were selected as the primary candidates for the heat-storage material. The initial phase of this assessment was directed to an EV battery being designed at CSPL for the ETX-II program. Specific tasks included the identification and characterization of potential fused salts, a determination of placement options for the salts within the battery, and an assessment of the ultimate benefit to the battery system. The results obtained to date for each of these tasks are presented in this paper.

Koenig, A.A.; Braithwaite, J.W.; Armijo, J.R.

1988-05-16T23:59:59.000Z

127

The Skin-Layer Ocean Heat Flux Instrument (SOHFI). Part II: Field Measurements of Surface Heat Flux and Solar Irradiance  

Science Conference Proceedings (OSTI)

The Skin-Layer Ocean Heat Flux Instrument (SOHFI) described by Sromovsky et al. (Part I, this issue) was field-tested in a combination of freshwater and ocean deployments. Solar irradiance monitoring and field calibration techniques were ...

L. A. Sromovsky; J. R. Anderson; F. A. Best; J. P. Boyle; C. A. Sisko; V. E. Suomi

1999-09-01T23:59:59.000Z

128

Evaluation of HOAPS-3 Ocean Surface Freshwater Flux Components  

Science Conference Proceedings (OSTI)

Today, latent heat flux and precipitation over the global ocean surface can be determined from microwave satellite data as a basis for estimating the related fields of the ocean surface freshwater flux. The Hamburg Ocean Atmosphere Parameters and ...

Axel Andersson; Christian Klepp; Karsten Fennig; Stephan Bakan; Hartmut Grassl; Jörg Schulz

2011-02-01T23:59:59.000Z

129

Numerical Simulation of a Latent Heat Storage System of a Solar-Aided Ground Source Heat Pump  

E-Print Network (OSTI)

In this study, the rectangular phase change storage tank (PCST) linked to a solar-aided ground source heat pump (SAGSHP) system is investigated experimentally and theoretically. The container of the phase change material (PCM) is the controlling unit of the phase change heat transfer model. It was solved numerically by an enthalpy-based finite difference method and was validated by experimental data. CaCl2•6H2O was used as the PCM in the latent heat storage system of SAGSHP system. In the tank, the PCMs are encapsulated in plastic kegs that are setting on the serpentine coil. The experiments were performed from March 12 to April 10, 2004 in the heating season of the transition period. In order to reflect the effects of the system, two days were chosen to compare the numerical results with experimental data. The inlet and outlet temperature of the water in the PCST, temperature of PCM and storage and emission heat of PCST were measured. The trends of the variation of numerical results and experimental data were in close agreement. Numerical results can reflect the operation mode of the system very well.

Wang, F.; Zheng, M.; Li, Z.; Lei, B.

2006-01-01T23:59:59.000Z

130

Downstream Heat Flux Profile vs. Midplane T Profile in Tokamaks  

SciTech Connect

The relationship between the midplane scrape-off-layer electron temperature profile and the parallel heat flux profile at the divertor in tokamaks is investigated. A model is applied which takes into account anisotropic thermal diffusion, in a rectilinear geometry with constant density. Eigenmode analysis is applied to the simplified problem with constant thermal diffusivities. A self-similar nonlinear solution is found for the more realistic problem with anisotropically temperature-dependent thermal diffusivities. Numerical solutions are developed for both cases, with spatially dependent heat flux emerging from the plasma. For both constant and temperature-dependent thermal diffusivities it is found that, below about one-half of its peak, the heat flux profile shape at the divertor, compared with the midplane temperature profile shape, is robustly described by the simplest two-point model. However the physical processes are not those assumed in the simplest two-point model, nor is the numerical coefficient relating q||div to Tmp ?||mp/L|| as predicted. For realistic parameters the peak in the heat flux, moreover, can be reduced by a factor of two or more from the two-point model scaling which fits the remaining profile. For temperature profiles in the SOL region above the x-point set by marginal stability, the heat flux profile to the divertor can be largely decoupled from the prediction of the two-point model. These results suggest caveats for data interpretation, and possibly favorable outcomes for divertor configurations with extended field lines.

Robert J. Goldston

2009-08-20T23:59:59.000Z

131

Deriving the Surface Soil Heat Flux from Observed Soil Temperature and Soil Heat Flux Profiles Using a Variational Data Assimilation Approach  

Science Conference Proceedings (OSTI)

A novel approach to infer surface soil heat fluxes from measured profiles of soil temperature, soil heat flux, and observations of the vegetation canopy temperature and the incoming shortwave radiation is evaluated for the Cabauw measurement ...

R. J. Ronda; F. C. Bosveld

2009-03-01T23:59:59.000Z

132

Carbon, water, and heat flux responses to experimental burning and drought  

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

Carbon, water, and heat flux responses to experimental burning and drought Carbon, water, and heat flux responses to experimental burning and drought in a tallgrass prairie Title Carbon, water, and heat flux responses to experimental burning and drought in a tallgrass prairie Publication Type Journal Article Year of Publication 2012 Authors Fischer, Marc L., Margaret S. Torn, David P. Billesbach, Geoffrey Doyle, Brian Northup, and Sebastien C. Biraud Journal Agricultural and Forest Meteorology Volume 166-167 Pagination 169-174 Keywords Carbon exchange, eddy covariance, Fire, Grassland, Prairie, Water stress Abstract Drought and fire are common disturbances to grassland ecosystems. We report two years of eddy covariance ecosystem-atmosphere fluxes and biometric variables measured in nearby burned and unburned pastures in the US Southern Great Plains. Over the course of the experiment, annual precipitation (∼600 mm yr-1) was lower than the long term mean (∼860 mm yr-1). Soil moisture decreased from productive conditions in March 2005 dry, unproductive conditions during the growing season starting in March 2006. Just prior to the burn in early March 2005, burned and unburned pastures contained 520 ± 60 and 360 ± 40 g C m-2 of total above ground biomass (AGB) and litter, respectively. The fire removed approximately 200 g C m-2 of litter and biomass. In the 2005 growing season following the burn, maximum green AGB was 450 ± 60 and 270 ± 40 g C m-2, with corresponding cumulative annual net ecosystem carbon exchange (NEE) of -330 and -150 g C m-2 for the burned and unburned pastures, respectively. In contrast to NEE, cumulative mean sensible heat and water fluxes were approximately equal in both pastures during the growing season, suggesting either an increase in water use efficiency or a decrease in evaporation in the burned relative to the unburned pasture. In the 2006 growing season, dry conditions decreased carbon uptake and latent heat, and increased sensible heat fluxes. Peak AGB was reduced to 210 ± 30 g C m-2 and 140 ± 30 g C m-2 in the burned and unburned pastures, respectively, while NEE was near zero. These results suggest that the lack of precipitation was responsible for most of the interannual variation in carbon exchange for these un-irrigated prairie pastures.

133

Effects of Cloud Seeding, Latent Heat of Fusion, and Condensate Loading on Cloud Dynamics and Precipitation Evolution: A Numerical Study  

Science Conference Proceedings (OSTI)

This study attempts to isolate the dynamic and microphysical effects of seeding. A two-dimensional, time-dependent cloud model has been used to simulate silver iodide (AgI) seeding of convective clouds. Two major dynamic effects (latent heat of ...

Harold D. Orville; Jeng-Ming Chen

1982-12-01T23:59:59.000Z

134

Sensitivity of Radiative Fluxes and Heating Rates to Cloud Microphysics  

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

Sensitivity of Radiative Fluxes and Heating Sensitivity of Radiative Fluxes and Heating Rates to Cloud Microphysics S. F. Iacobellis and R. C. J. Somerville Scripps Institution of Oceanography University of California, San Diego La Jolla, California G. M. McFarquhar University of Illinois at Urbana-Champaign Urbana, Illinois D. L. Mitchell Desert Research Institute Reno, Nevada Introduction A single-column model (SCM) is used to examine the sensitivity of basic quantities such as atmospheric radiative heating rates and surface and top of atmosphere (TOA) radiative fluxes to various parameter- izations of clouds and cloud microphysics. The SCM was run at the Atmospheric Radiation Measurement (ARM) Program's Southern Great Plains (SGP), Tropical Western Pacific (TWP), and North Slope of Alaska (NSA) sites using forcing data derived from forecast products. The forecast

135

Remote high-temperature insulatorless heat-flux gauge  

DOE Patents (OSTI)

A remote optical heat-flux gauge for use in extremely high temperature environments is described. This application is possible because of the use of thermographic phosphors as the sensing media, and the omission of the need for an intervening layer of insulator between phosphor layers. The gauge has no electrical leads, but is interrogated with ultraviolet or laser light. The luminescence emitted by the two phosphor layers, which is indicative of the temperature of the layers, is collected and analyzed in order to determine the heat flux incident on the surface being investigated. The two layers of thermographic phosphor must be of different materials to assure that the spectral lines collected will be distinguishable. Spatial heat-flux measurements can be made by scanning the light across the surface of the gauge.

Noel, Bruce W. (Espanola, NM)

1993-01-01T23:59:59.000Z

136

Remote high-temperature insulatorless heat-flux gauge  

DOE Patents (OSTI)

A remote optical heat-flux gauge for use in extremely high temperature environments is described. This application is possible because of the use of thermographic phosphors as the sensing media, and the omission of the need for an intervening layer of insulator between phosphor layers. The gauge has no electrical leads, but is interrogated with ultraviolet or laser light. The luminescence emitted by the two phosphor layers, which is indicative of the temperature of the layers, is collected and analyzed in order to determine the heat flux incident on the surface being investigated. The two layers of thermographic phosphor must be of different materials to assure that the spectral lines collected will be distinguishable. Spatial heat-flux measurements can be made by scanning the light across the surface of the gauge. 3 figures.

Noel, B.W.

1993-12-28T23:59:59.000Z

137

Remote high temperature insulatorless heat-flux gauge  

DOE Patents (OSTI)

A remote optical heat-flux gauge for use in high temperature environments. This application is possible because of the use of thermographic phosphors as the sensing media, and the omission of the need for an intervening layer of insulator between phosphor layers. The gauge has no electrical leads, but is interrogated with ultraviolet light. The luminescence emitted by the two thermographic-phosphor layers, which is indicative of the temperature of the layers, is collected and analyzed in order to determine the heat flux incident on the surface being investigated. The two layers of thermographic phosphor must be of different materials to assure that the spectral lines collected will be distinguishable. Spatial heat flux measurements can be made by scanning the light across the surface of the gauge.

Noel, B.W.

1992-12-31T23:59:59.000Z

138

Interpretation of Flux-Profile Observations at ITCE (1976)  

Science Conference Proceedings (OSTI)

At an International Turbulence Comparison Experiment (ITCE) in Australia (1976), wind, temperature and humidity profiles, plus vertical fluxes of momentum, sensible heat and latent heat were measured for a limited range of unstable conditions, ...

R. J. Francey; J. R. Garratt

1981-06-01T23:59:59.000Z

139

Spatially averaged heat flux and convergence measurements at the ARM regional flux experiment  

SciTech Connect

Cloud formation and its relation to climate change is the greatest weakness in current numerical climate models. Surface heat flux in some cases causes clouds to form and in other to dissipate and the differences between these cases are subtle enough to make parameterization difficult in a numerical model. One of the goals of the DOE Atmospheric Radiation Measurement program is to make long term measurements at representative sites to improve radiation and cloud formation parameterization. This paper compares spatially averaged optical measurements of heat flux and convergence with a goal of determining how point measurements of heat fluxes scale up to the larger scale used for climate modeling. It was found that the various optical techniques used in this paper compared well with each other and with independent measurements. These results add confidence that spatially averaging optical techniques can be applied to transform point measurements to the larger scales needed for mesoscale and climate modeling. 10 refs., 6 figs. (MHB)

Porch, W.; Barnes, F.; Buchwald, M.; Clements, W.; Cooper, D.; Hoard, D. (Los Alamos National Lab., NM (United States)); Doran, C.; Hubbe, J.; Shaw, W. (Pacific Northwest Lab., Richland, WA (United States)); Coulter, R.; Martin, T. (Argonne National Lab., IL (United States)); Kunkel, K. (Illinois State Water Survey, Champaign, IL (United States))

1991-01-01T23:59:59.000Z

140

DIRECT MEASUREMENT OF HEAT FLUX FROM COOLING LAKE THERMAL IMAGERY  

SciTech Connect

Laboratory experiments show a linear relationship between the total heat flux from a water surface to air and the standard deviation of the surface temperature field, {sigma}, derived from thermal images of the water surface over a range of heat fluxes from 400 to 1800 Wm{sup -2}. Thermal imagery and surface data were collected at two power plant cooling lakes to determine if the laboratory relationship between heat flux and {sigma} exists in large heated bodies of water. The heat fluxes computed from the cooling lake data range from 200 to 1400 Wm{sup -2}. The linear relationship between {sigma} and Q is evident in the cooling lake data, but it is necessary to apply band pass filtering to the thermal imagery to remove camera artifacts and non-convective thermal gradients. The correlation between {sigma} and Q is improved if a correction to the measured {sigma} is made that accounts for wind speed effects on the thermal convection. Based on more than a thousand cooling lake images, the correlation coefficients between {sigma} and Q ranged from about 0.8 to 0.9.

Garrett, A; Eliel Villa-Aleman, E; Robert Kurzeja, R; Malcolm Pendergast, M; Timothy Brown, T; Saleem Salaymeh, S

2007-12-19T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Heat Transfer and Latent Heat Storage in Inorganic Molten Salts for Concentrating Solar Power Plants  

DOE Green Energy (OSTI)

The report documents the specialty coatings, the composition and morphology of hypereutectic salt mixtures and the results from the experiment conducted with the active heat exchanger along with the lessons learnt during experimentation.

Mathur, Anoop [Terrafore Inc.

2013-08-14T23:59:59.000Z

142

Computing Surface Fluxes from Mesonet Data  

Science Conference Proceedings (OSTI)

By using air–vegetation–soil layer coupled model equations as weak constraints, a variational method is developed to compute sensible and latent heat fluxes from conventional observations obtained at meteorological surface stations. This method ...

Binbin Zhou; Qin Xu

1999-09-01T23:59:59.000Z

143

Direct evaluation of transient surface temperatures and heat fluxes  

SciTech Connect

Evaluations of transient surface temperatures resulting from the absorption of radiation are required in laser fusion reactor systems studies. A general method for the direct evaluation of transient surface temperatures and heat fluxes on the boundaries of bounded media is developed by constructing fundamental solutions of the scalar Helmholtz equation and performing certain elementary integrations. (auth)

Axford, R.A.

1975-08-01T23:59:59.000Z

144

Ocean Heat Flux in the Central Weddell Sea during Winter  

Science Conference Proceedings (OSTI)

Seasonal sea ice, which plays a pivotal role in air–sea interaction in the Weddell Sea (a region of large deep-water formation with potential impact on climate), depends critically on heat flux from the deep ocean. During the austral winter of ...

Miles G. McPhee; Christoph Kottmeier; James H. Morison

1999-06-01T23:59:59.000Z

145

Estimation of Heat and Mass Fluxes Over Arctic Leads  

Science Conference Proceedings (OSTI)

Recent work on the turbulent transfer of scalar quantities following a step increase in the surface value of the scalar is directly applicable to the problem of estimating heat and mass transfer from Arctic leads in winter. If the turbulent flux ...

Edgar L. Andreas

1980-12-01T23:59:59.000Z

146

The Sensitivity of Surface Fluxes to Soil Water Content in Three Land Surface Schemes  

Science Conference Proceedings (OSTI)

Evaporative fraction (EF; the ratio of latent heat flux to the sum of the latent plus sensible heat fluxes) can be measured in the field to an accuracy of about 10%. In this modeling study, the authors try to determine to what accuracy soil ...

Paul A. Dirmeyer; Fanrong J. Zeng; Agnès Ducharne; Jean C. Morrill; Randal D. Koster

2000-04-01T23:59:59.000Z

147

Analysis of selected surface characteristics and latent heat storage for passive solar space heating  

DOE Green Energy (OSTI)

Results are presented of an analysis of the value of various technical improvements in the solar collector and thermal storage subsystems of passive solar residential, agricultural, and industrial systems for two regions of the country. The evaluated improvements are: decreased emissivity and increased absorptivity of absorbing surfaces, decreased reflectivity, and decreased emissivity of glazing surface, and the substitution of sensible heat storage media with phase change materials. The value of each improvement is estimated by the additional energy savings resulting from the improvement.

Fthenakis, V.; Leigh, R.

1981-12-01T23:59:59.000Z

148

Micro and nanostructured surfaces for enhanced phase change heat transfer  

E-Print Network (OSTI)

Two-phase microchannel heat sinks are of significant interest for thermal management applications, where the latent heat of vaporization offers an efficient method to dissipate large heat fluxes in a compact device. However, ...

Chu, Kuang-Han, Ph. D. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

149

Method of fission heat flux determination from experimental data  

DOE Patents (OSTI)

A method is provided for determining the fission heat flux of a prime specimen inserted into a specimen of a test reactor. A pair of thermocouple test specimens are positioned at the same level in the holder and a determination is made of various experimental data including the temperature of the thermocouple test specimens, the temperature of bulk water channels located in the test holder, the gamma scan count ratios for the thermocouple test specimens and the prime specimen, and the thicknesses of the outer clads, the fuel fillers, and the backclad of the thermocouple test specimen. Using this experimental data, the absolute value of the fission heat flux for the thermocouple test specimens and prime specimen can be calculated.

Paxton, Frank A. (Schenectady, NY)

1999-01-01T23:59:59.000Z

150

Modeling Surface Sensible Heat Flux Using Surface Radiative Temperatures in a Simple Urban Area  

Science Conference Proceedings (OSTI)

Sensible heat fluxes over a light industrial area in Vancouver, British Columbia, Canada, are analyzed from observed tower fluxes and modeled using a bulk heat transfer approach. The bulk transfer models are initialized using remotely sensed ...

J. A. Voogt; C. S. B. Grimmond

2000-10-01T23:59:59.000Z

151

Sensible Heat Flux-Radiometric Surface Temperature Relationship for Eight Semiarid Areas  

Science Conference Proceedings (OSTI)

Measurements of sensible heat flux, radiometric surface temperature, air temperature, and wind speed made at eight semiarid rangeland sites were used to investigate the sensible heat flux-aerodynamic resistance relationship. The individual sites ...

J. B. Stewart; W. P. Kustas; K. S. Humes; W. D. Nichols; M. S. Moran; H. A. R. de Bruin

1994-09-01T23:59:59.000Z

152

Annual, Seasonal, and Interannual Variability of Air–Sea Heat Fluxes in the Indian Ocean  

Science Conference Proceedings (OSTI)

This study investigated the accuracy and physical representation of air–sea surface heat flux estimates for the Indian Ocean on annual, seasonal, and interannual time scales. Six heat flux products were analyzed, including the newly developed ...

Lisan Yu; Xiangze Jin; Robert A. Weller

2007-07-01T23:59:59.000Z

153

Moisture Budget Analysis of TOGA COARE Area Using SSM/I-Retrieved Latent Heating and Large-Scale Q2 Estimates  

Science Conference Proceedings (OSTI)

This study addresses the retrieval of tropical open-ocean latent heating using Special Sensor Microwave Imager (SSM/I) satellite measurements. The analysis is carried out for the Tropical Ocean and Global Atmosphere Coupled Ocean–Atmosphere ...

Song Yang; Eric A. Smith

1999-06-01T23:59:59.000Z

154

A Latent Heat Retrieval and Its Effects on the Intensity and Structure Change of Hurricane Guillermo (1997). Part I: The Algorithm and Observations  

Science Conference Proceedings (OSTI)

Despite the fact that latent heating in cloud systems drives many atmospheric circulations, including tropical cyclones, little is known of its magnitude and structure, largely because of inadequate observations. In this work, a reasonably high-...

Stephen R. Guimond; Mark A. Bourassa; Paul D. Reasor

2011-08-01T23:59:59.000Z

155

A Latent Heat Retrieval and Its Effects on the Intensity and Structure Change of Hurricane Guillermo (1997). Part II: Numerical Simulations  

Science Conference Proceedings (OSTI)

In Part I of this study, a new algorithm for retrieving the latent heat field in tropical cyclones from airborne Doppler radar was presented and fields from rapidly intensifying Hurricane Guillermo (1997) were shown. In Part II, the usefulness and ...

Stephen R. Guimond; Jon M. Reisner

2012-11-01T23:59:59.000Z

156

Spray cooling heat-transfer with subcooled trichlorotrifluoroethane (Freon-113) for vertical constant heat flux surfaces  

SciTech Connect

Experiments were done using subcooled Freon-113 sprayed vertically downward. Local and average heat transfers were investigated fro Freon-113 sprays with 40 C subcooling, droplet sizes 200-1250{mu}m, and droplet breakup velocities 5-29 m/s. Full-cone type nozzles were used to generate the spray. Test assemblies consisted of 1 to 6 7.62 cm vertical constant heat flux surfaces parallel with each other and aligned horizontally. Distance between heated surfaces was varied from 6.35 to 76.2 mm. Steady state heat fluxes as high as 13 W/cm{sup 2} were achieved. Dependence on the surface distance from axial centerline of the spray was found. For surfaces sufficiently removed from centerline, local and average heat transfers were identical and correlated by a power relation of the form seen for normal-impact sprays which involves the Weber number, a nondimensionalized temperature difference, and a mass flux parameter. For surfaces closer to centerline, the local heat transfer depended on vertical location on the surface while the average heat transfer was described by a semi-log correlation involving the same parameters. The heat transfer was independent of the distance (gap) between the heated surfaces for the gaps investigated.

Kendall, C.M. [Lawrence Livermore National Lab., CA (United States); Holman, J.P. [Southern Methodist Univ., Dallas, TX (United States). Dept. of Mechanical Engineering

1996-06-06T23:59:59.000Z

157

The Tropical Dynamical Response to Latent Heating Estimates Derived from the TRMM Precipitation Radar  

Science Conference Proceedings (OSTI)

A 3-yr (1998–2000) climatology of near-surface rainfall and stratiform rain fraction observed by the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) was used to calculate the four-dimensional distribution of tropical latent ...

Courtney Schumacher; Robert A. Houze Jr.; Ian Kraucunas

2004-06-01T23:59:59.000Z

158

Mean and Variability of Air-Sea Heat Fluxes in the Indian Ocean  

E-Print Network (OSTI)

-sea heat Fluxes) Project: blended product planned activity: daily, 1º-grid, mid 1950's ­ present currently available: daily, 1º-grid, 1988-2003 #12;OAFlux (Objectively Analyzed Air-sea Heat Fluxes) For the GlobalMean and Variability of Air-Sea Heat Fluxes in the Indian Ocean Lisan Yu Woods Hole Oceanographic

Yu, Lisan

159

Estimation of the Surface Heat Flux Response to Sea Surface Temperature Anomalies over the Global Oceans  

Science Conference Proceedings (OSTI)

The surface heat flux response to underlying sea surface temperature (SST) anomalies (the surface heat flux feedback) is estimated using 42 yr (1956–97) of ship-derived monthly turbulent heat fluxes and 17 yr (1984–2000) of satellite-derived ...

Sungsu Park; Clara Deser; Michael A. Alexander

2005-11-01T23:59:59.000Z

160

AutoFlux -what ARE we doing? An air-sea interaction experiment  

E-Print Network (OSTI)

the "sensible heat flux" and the evaporation exchange is called the "latent heat flux". North Atlantic part the air above it and so heat is transferred from the surface water to the atmosphere, just as a cooker heats a saucepan from beneath. A dramatic example of how the ocean heats the atmosphere is the Gulf

National Oceanography Centre Southampton

Note: This page contains sample records for the topic "flux latent heat" 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

The Distribution of Surface Fluxes and Boundary Layer Divergence in Midlatitude Ocean Storms  

Science Conference Proceedings (OSTI)

Surface meteorological observations have been used to calculate the distributions of surface fluxes of momentum, sensible heat, and latent heat and the distributions of surface divergence and curl of surface stress which are characteristic of ...

Robert G. Fleagle; Wendell A. Nuss

1985-04-01T23:59:59.000Z

162

Evaluation of Surface Flux Parameterizations with Long-Term ARM Observations  

Science Conference Proceedings (OSTI)

Surface momentum, sensible heat, and latent heat fluxes are critical for atmospheric processes such as clouds and precipitation, and are parameterized in a variety of models ranging from cloud-resolving models to large-scale weather and climate ...

Gang Liu; Yangang Liu; Satoshi Endo

2013-02-01T23:59:59.000Z

163

Development and Testing of Instrumentation for UAV-Based Flux Measurements within Terrestrial and Marine Atmospheric Boundary Layers  

Science Conference Proceedings (OSTI)

Instrumentation packages have been developed for small (18–28 kg) unmanned aerial vehicles (UAVs) to measure momentum fluxes as well as latent, sensible, and radiative heat fluxes in the atmospheric boundary layer (ABL) and the topography below. ...

Benjamin D. Reineman; Luc Lenain; Nicholas M. Statom; W. Kendall Melville

2013-07-01T23:59:59.000Z

164

Calculation of heating values for the high flux isotope reactor  

Science Conference Proceedings (OSTI)

Calculating the amount of energy released by a fission reaction (fission Q value) and the heating rate distribution in a nuclear reactor is an important part of the safety analysis. However, these calculations can become very complex. One of the codes that can be used for this type of analyses is the Monte Carlo transport code MCNP5. Currently it is impossible to calculate the Q value and heating rate disposition for delayed beta and delayed gamma particles directly from MCNP5. The purpose of this paper is to outline a rigorous method for indirectly calculating the Q values and heating rates in the High Flux Isotope Reactor (HFIR), based on previous similar studies carried out for very high-temperature reactor configurations. This method has been applied in this study to calculate heating rates for the beginning of cycle (BOC) and end-of-cycle (EOC) states of HFIR. In addition, the BOC results obtained for HFIR are compared with corresponding results for the Advanced Test Reactor. The fission Q value for HFIR was calculated as 200.2 MeV for the BOC and 201.3 MeV for the EOC. It was also determined that 95.1% and 95.4% of the heat was deposited within the HFIR fuel plates for the BOC and EOC models, respectively. This methodology can also be used for heating rate calculations for HFIR experiments. (authors)

Peterson, J.; Ilas, G. [Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6172 (United States)

2012-07-01T23:59:59.000Z

165

Calculation of Heating Values for the High Flux Isotope Reactor  

SciTech Connect

Calculating the amount of energy released by a fission reaction (fission Q value) and the heating rate distribution in a nuclear reactor is an important part of the safety analysis. However, these calculations can become very complex. One of the codes that can be used for this type of analyses is the Monte Carlo transport code MCNP5. Currently it is impossible to calculate the Q value and heating rate disposition for delayed beta and delayed gamma particles directly from MCNP5. The purpose of this paper is to outline a rigorous method for indirectly calculating the Q values and heating rates in the High Flux Isotope Reactor (HFIR), based on previous similar studies carried out for very high-temperature reactor configurations. This method has been applied in this study to calculate heating rates for the beginning of cycle (BOC) and end-of-cycle (EOC) states of HFIR. In addition, the BOC results obtained for HFIR are compared with corresponding results for the Advanced Test Reactor. The fission Q value for HFIR was calculated as 200.2 MeV for the BOC and 201.3 MeV for the EOC. It was also determined that 95.1% and 95.4% of the heat was deposited within the HFIR fuel plates for the BOC and EOC models, respectively. This methodology can also be used for heating rate calculations for HFIR experiments.

Peterson, Joshua L [ORNL; Ilas, Germina [ORNL

2012-01-01T23:59:59.000Z

166

The Sensitivity of the Simulated Normal and Enhanced C02 Climates to Different Heat Transport Parameterizations in a Two-Dimensional Multilevel Energy Balance Model  

Science Conference Proceedings (OSTI)

Atmospheric sensible and latent heat fluxes constitute an important component of the total poleward energy transport in the climate system. The authors investigate the relative role of these heat fluxes in normal and enhanced C02 warming ...

Douglas Chan; Kaz Higuchi; Charles A. Lin

1995-04-01T23:59:59.000Z

167

Boundary Layer Characteristics over Areas of Inhomogeneous Surface Fluxes  

Science Conference Proceedings (OSTI)

This paper describes results from a June 1992 field program to study the response of the boundary layer over a site with well-defined extreme differences in sensible and latent heat fluxes over clearly separated areas, each with characteristic ...

J. C. Doran; W. J. Shaw; J. M. Hubbe

1995-02-01T23:59:59.000Z

168

Estimation of turbulent surface heat fluxes using sequences of remotely sensed land surface temperature  

E-Print Network (OSTI)

Fluxes of heat and moisture at the land-surface play a significant role in the climate system. These fluxes interact with the overlying atmosphere and influence the characteristics of the planetary boundary layer (e.g. ...

Bateni, Sayed Mohyeddin

2011-01-01T23:59:59.000Z

169

Measurements of Turbulent Fluxes of Momentum and Sensible Heat over the Labrador Sea  

Science Conference Proceedings (OSTI)

Turbulent fluxes of momentum and sensible heat were estimated from sonic anemometer measurements gathered over the Labrador Sea during a winter cruise of the R/V Knorr. The inertial dissipation method was used to calculate turbulent fluxes of ...

Karl Bumke; U. Karger; K. Uhlig

2002-02-01T23:59:59.000Z

170

Atmospheric Forcing of the Winter Air–Sea Heat Fluxes over the Northern Red Sea  

Science Conference Proceedings (OSTI)

The influence of the atmospheric circulation on the winter air–sea heat fluxes over the northern Red Sea is investigated during the period 1985–2011. The analysis based on daily heat flux values reveals that most of the net surface heat exchange ...

Vassilis P. Papadopoulos; Yasser Abualnaja; Simon A. Josey; Amy Bower; Dionysios E. Raitsos; Harilaos Kontoyiannis; Ibrahim Hoteit

2013-03-01T23:59:59.000Z

171

Radial heat flux limits in potassium heat pipes: An experimental and analytical investigation  

SciTech Connect

A radial flux limit of 147 W/cm{sup 2} at the wetted inner tube wall has been demonstrated with a Nb-1%Zr/K heat pipe, a flux 5 times greater than the previously accepted safe design level of 25-30 W/cm{sup 2}. The wick structure was an annular gap type fabricated from 100 {times} 100 mesh Nb-1%Zr screen. Rigorous fabrication and cleaning procedures are believed to be critical to good wetting, resulting in significantly reduced active nucleation site size and a higher boiling limit. The procedure used to clean this heat pipe included acid wash, Freon-TF degrease, ethanol wash, high-vacuum firing, and operation as a lithium heat pipe. A heat pipe boiling limit model, based on the active nucleation site radius, is described. An active nucleation site radius of 6 {times} 10{sup -6} m (2.4 {times} 10{sup -4} in) correlates the radial flux boiling limit measured in these tests. 4 refs., 2 figs.

Woloshun, K.A.; Sena, J.T.; Keddy, E.S.; Merrigan, M.A.

1989-01-01T23:59:59.000Z

172

The boardman regional flux experiment  

SciTech Connect

A field campaign was carried out near Boardman, Oregon, to study the effects of subgrid-scale variability of sensible- and latent-heat fluxes on surface boundary-layer properties. The experiment involved three U.S. Department of Energy laboratories, one National Oceanic and Atmospheric Administration laboratory, and several universities. The experiment was conducted in a region of severe contrasts in adjacent surface types that accentuated the response of the atmosphere to variable surface forcing. Large values of sensible-heat flux and low values of latent-heat flux characterized a sagebrush steppe area; significantly smaller sensible-heat fluxes and much larger latent-heat fluxes were associated with extensive tracts of irrigated farmland to the north, east, and west of the steppe. Data were obtained from an array of surface flux stations, remote-sensing devices, an instrumented aircraft, and soil and vegetation measurements. The data will be used to address the problem of extrapolating from a limited number of local measurements to area-averaged values of fluxes suitable for use in global climate models. 16 refs., 13 figs.

Doran, J.C.; Hubbe, J.M.; Kirkham, R.R.; Shaw, W.J.; Whiteman, C.D. (Pacific Northwest Lab., Richland, WA (United States)); Barnes, F.J.; Cooper, D.; Porch, W. (Los Alamos National Lab., NM (United States)); Coulter, R.L.; Cook, D.R.

1992-11-01T23:59:59.000Z

173

Description of heat flux measurement methods used in hydrocarbon and propellant fuel fires at Sandia.  

DOE Green Energy (OSTI)

The purpose of this report is to describe the methods commonly used to measure heat flux in fire applications at Sandia National Laboratories in both hydrocarbon (JP-8 jet fuel, diesel fuel, etc.) and propellant fires. Because these environments are very severe, many commercially available heat flux gauges do not survive the test, so alternative methods had to be developed. Specially built sensors include 'calorimeters' that use a temperature measurement to infer heat flux by use of a model (heat balance on the sensing surface) or by using an inverse heat conduction method. These specialty-built sensors are made rugged so they will survive the environment, so are not optimally designed for ease of use or accuracy. Other methods include radiometers, co-axial thermocouples, directional flame thermometers (DFTs), Sandia 'heat flux gauges', transpiration radiometers, and transverse Seebeck coefficient heat flux gauges. Typical applications are described and pros and cons of each method are listed.

Nakos, James Thomas

2010-12-01T23:59:59.000Z

174

Temperature, thermal-conductivity, and heat-flux data,Raft River...  

Open Energy Info (EERE)

Temperature, thermal-conductivity, and heat-flux data,Raft River area, Cassia County, Idaho (1974-1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report:...

175

Quantitative method for measuring heat flux emitted from a cryogenic object  

DOE Patents (OSTI)

The present invention is a quantitative method for measuring the total heat flux, and of deriving the total power dissipation, of a heat-fluxing object which includes the steps of placing an electrical noise-emitting heat-fluxing object in a liquid helium bath and measuring the superfluid transition temperature of the bath. The temperature of the liquid helium bath is thereafter reduced until some measurable parameter, such as the electrical noise, exhibited by the heat-fluxing object or a temperature-dependent resistive thin film in intimate contact with the heat-fluxing object, becomes greatly reduced. The temperature of the liquid helum bath is measured at this point. The difference between the superfluid transition temperature of the liquid helium bath surrounding the heat-fluxing object, and the temperature of the liquid helium bath when the electrical noise emitted by the heat-fluxing object becomes greatly reduced, is determined. The total heat flux from the heat-fluxing object is determined as a function of this difference between these temperatures. In certain applications, the technique can be used to optimize thermal design parameters of cryogenic electronics, for example, Josephson junction and infrared sensing devices.

Duncan, R.V.

1993-03-16T23:59:59.000Z

176

Quantitative method for measuring heat flux emitted from a cryogenic object  

DOE Patents (OSTI)

The present invention is a quantitative method for measuring the total heat flux, and of deriving the total power dissipation, of a heat-fluxing object which includes the steps of placing an electrical noise-emitting heat-fluxing object in a liquid helium bath and measuring the superfluid transition temperature of the bath. The temperature of the liquid helium bath is thereafter reduced until some measurable parameter, such as the electrical noise, exhibited by the heat-fluxing object or a temperature-dependent resistive thin film in intimate contact with the heat-fluxing object, becomes greatly reduced. The temperature of the liquid helum bath is measured at this point. The difference between the superfluid transition temperature of the liquid helium bath surrounding the heat-fluxing object, and the temperature of the liquid helium bath when the electrical noise emitted by the heat-fluxing object becomes greatly reduced, is determined. The total heat flux from the heat-fluxing object is determined as a function of this difference between these temperatures. In certain applications, the technique can be used to optimize thermal design parameters of cryogenic electronics, for example, Josephson junction and infra-red sensing devices.

Duncan, Robert V. (Tijeras, NM)

1993-01-01T23:59:59.000Z

177

Estimation of the Latent Heat Flux over Full Canopy Covers from the Radiative Temperature  

Science Conference Proceedings (OSTI)

This paper examines the bulk aerodynamic method and proposes an alternative algorithm for estimating evapotranspiration from radiative temperature over unstressed full-canopy cover crops. Both approaches are studied using calibration and ...

M. Ibáñez; P. J. Pérez; J. I. Rosell; F. Castellví

1999-04-01T23:59:59.000Z

178

A Parameterization of Transient Eddy Heat Flux on a Beta-Plane  

Science Conference Proceedings (OSTI)

A parameterization of transient eddy heat flux is developed which incorporates baroclinic wave behavior in a continuously stratified fluid on a ?-plane. The meridional and vertical heat transports are more sensitive to forced changes in the mean ...

Lee E. Branscome

1983-10-01T23:59:59.000Z

179

An Investigation of the Influence of Latent Heat Release on Cold-Frontal Motion  

Science Conference Proceedings (OSTI)

The effects of condensational heating on cold-frontal translation speed are explored through the use of potential vorticity (PV) diagnostics and model sensitivity experiments. It is hypothesized that condensational heating can lead to faster ...

Heather Dawn Reeves; Gary M. Lackmann

2004-12-01T23:59:59.000Z

180

Candidate chemical systems for air cooled, solar powered, absorption air conditioner design. Part II. Solid absorbents, high latent heat refrigerants  

DOE Green Energy (OSTI)

Work done in attempting to qualify absorption refrigeration systems based on refrigerants with intermediate latent heats of vaporization is summarized. In practice, these comprise methanol, ammonia, and methylamine. A wide variety of organic substances, salts, and mixtures were evaluated in as systematic a manner as possible. Several systems of interest are described. The system, LiClO/sub 3/--LiBr--H/sub 2/O, is a good back up system to our first choice of an antifreeze additive system, and thermodynamically promising but subject to some inconvenient materials limitations. The system, LiBr/ZnBr/sub 2/--methanol, is thermodynamically promising but requires additional kinetic qualification. Chemical stability of the system, LiCNS--ammonia/methylamine with various other third components, does not appear to be adequate for a long-lived system.

Biermann, W. J.

1978-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Factors Regulating the Air–Sea Heat Fluxes Regime over the Aegean Sea  

Science Conference Proceedings (OSTI)

The authors examine the impact of low-frequency atmospheric forcings on the air–sea heat fluxes over the Aegean Sea. The correlation between the air–sea heat flux components and three established [North Atlantic Oscillation (NAO), east Atlantic–...

Vassilis P. Papadopoulos; Aristides Bartzokas; Themistoklis Chronis; Dimitris Georgopoulos; George Ferentinos

2012-01-01T23:59:59.000Z

182

Can Shipboard Measurements Reveal Secular Changes in Tropical Air–Sea Heat Flux?  

Science Conference Proceedings (OSTI)

A new Comprehensive Ocean-Atmosphere Data Set for the period 1854–1979 will soon become available for studies of secular climate changes in ocean surface heat flux. Of the observed variables from which heat flux is calculated, wind speed and sea ...

C. S. Ramage

1984-02-01T23:59:59.000Z

183

A Model for the Influence of Wind and Oceanic Currents on the Size of a Steady-State Latent Heat Coastal Polynya  

Science Conference Proceedings (OSTI)

This paper presents a model for determining the size and shape of a steady-state latent heat coastal polynya in terms of the following free parameters: 1) the frazil ice production rate (F); 2) the wind stress (?); 3) the surface ocean velocity ...

A. J. Willmott; M. A. Morales Maqueda; M. S. Darby

1997-10-01T23:59:59.000Z

184

The Boardman Regional Flux Experiment  

Science Conference Proceedings (OSTI)

A field campaign was carried out near Boardman, Oregon, to study the effects of subgrid-scale variability of sensible-and latent-heat fluxes on surface boundary-layer properties. The experiment involved three U.S. Department of Energy ...

J. C. Doran; J. M. Hubbe; R. R. Kirkham; W. J. Shaw; C. D. Whiteman; F. J. Barnes; D. Cooper; W. Porch; R. L. Coutler; D. R. Cook; R. L. Hart; W. Gao; T. J. Martin; J. D. Shannon; T. L. Crawford; D. D. Baldocchi; R. J. Dobosy; T. P. Meyers; L. Balick; W. A. Dugas; R. Hicks; L. Fritschen; L. Hipps; E. Swiatek; K. E. Kunkel

1992-11-01T23:59:59.000Z

185

The Effect of Soil Thermal Conductivity Parameterization on Surface Energy Fluxes and Temperatures  

Science Conference Proceedings (OSTI)

The sensitivity of sensible and latent heat fluxes and surface temperatures to the parameterization of the soil thermal conductivity is demonstrated using a soil vegetation atmosphere transfer scheme (SVATS) applied to intensive field campaigns (...

C. D. Peters-Lidard; E. Blackburn; X. Liang; E. F. Wood

1998-04-01T23:59:59.000Z

186

Measured and Parameterized Energy Fluxes for Atlantic Transects of R/V Polarstern  

Science Conference Proceedings (OSTI)

Sensible and latent heat fluxes were estimated from turbulence measurements gathered during several Atlantic transects of the R/V Polarstern. The inertial dissipation method was used to analyze the data. Resulting bulk transfer coefficients were ...

Karl Bumke; Michael Schlundt; John Kalisch; Andreas Macke; Henry Kleta

187

A variational method for estimating surface fluxes with mass conservation constraint  

Science Conference Proceedings (OSTI)

Based on the similarity theory of the atmospheric surface layer and the mass conservation principle, a new scheme using a variational method is developed to estimate the surface momentum and sensible and latent heat fluxes. In this scheme, the ...

Sen Li; Zhong Zhong; Weidong Guo; Wei Lu

188

Subcooled flow boiling heat transfer and critical heat flux in water-based nanofluids at low pressure  

E-Print Network (OSTI)

A nanofluid is a colloidal suspension of nano-scale particles in water, or other base fluids. Previous pool boiling studies have shown that nanofluids can improve the critical heat flux (CHF) by as much as 200%. In this ...

Kim, Sung Joong, Ph. D. Massachusetts Institute of Technology

2009-01-01T23:59:59.000Z

189

Temperature, thermal-conductivity, and heat-flux data,Raft River area,  

Open Energy Info (EERE)

Temperature, thermal-conductivity, and heat-flux data,Raft River area, Temperature, thermal-conductivity, and heat-flux data,Raft River area, Cassia County, Idaho (1974-1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Temperature, thermal-conductivity, and heat-flux data,Raft River area, Cassia County, Idaho (1974-1976) Details Activities (1) Areas (1) Regions (0) Abstract: Basin and Range Province; Cassia County Idaho; economic geology; exploration; geophysical surveys; geothermal energy; heat flow; heat flux; Idaho; North America; Raft River basin; south-central Idaho; surveys; temperature; thermal conductivity; United States; USGS Author(s): Urban, T.C.; Diment, W.H.; Nathenson, M.; Smith, E.P.; Ziagos, J.P.; Shaeffer, M.H. Published: Open-File Report - U. S. Geological Survey, 1/1/1986 Document Number: Unavailable

190

Atmospheric Heat Engines on Earth and Mars  

Science Conference Proceedings (OSTI)

The character of the Earth's atmospheric heat engine depends, inter alia, on the relatively tight linkage between surface fluxes of energy and of H20. On Mars, on the other hand, H2O-based latent heat fluxes are only a trivial fraction of total ...

J. R. Philip

1987-06-01T23:59:59.000Z

191

Nonclassical Mesoscale Circulations Caused by Surface Sensible Heat-Flux Gradients  

Science Conference Proceedings (OSTI)

Significant spatial heterogeneities of daytime surface sensible heat flux are common over land within mesoscale domains. Thermally induced circulations, similar to the sea/lake breeze [termed nonclassical mesoscale circulations (NCMSs)], are ...

M. Segal; R. W. Arritt

1992-10-01T23:59:59.000Z

192

Diffusivity, Kinetic Energy Dissipation, and Closure Theories for the Poleward Eddy Heat Flux  

Science Conference Proceedings (OSTI)

Diffusive eddy closure theory for estimating the poleward heat flux is reexamined and tested in the context of a two-layer homogeneous model. Consideration of the inverse energy cascade induced by baroclinic turbulence on the ? plane leads to an ...

G. Lapeyre; I. M. Held

2003-12-01T23:59:59.000Z

193

Modeling the Surface Heat Flux Response to Long-Lived SST Anomalies in the North Atlantic  

Science Conference Proceedings (OSTI)

An atmospheric general circulation model (AGCM), a simplified atmospheric model (SAM) of surface heat flux, and various idealized analytic models have been used to investigate the atmospheric response over the North Atlantic to SST anomalies ...

S. B. Power; R. Kleeman; R. A. Colman; B. J. McAvaney

1995-09-01T23:59:59.000Z

194

Empirical Models of the Eddy Heat Flux and Vertical Shear on Short Time Scales  

Science Conference Proceedings (OSTI)

The relationship between the eddy heat flux and vertical shear in the extratropical atmosphere is studied by developing various linear stochastic models fitted to the observed January and July Northern Hemispheric data. Models are univariate or ...

Steven J. Ghan

1984-02-01T23:59:59.000Z

195

Comparison of the Global Meridional Ekman Heat Flux Estimated from Four Wind Sources  

Science Conference Proceedings (OSTI)

The variability in the meridional Ekman heat flux estimated using wind data from four different sources is examined. The wind vectors are obtained from the European Remote Sensing (ERS), Quick Scatterometer (Quikscat), and Special Sensor ...

Olga T. Sato; Paulo S. Polito

2005-01-01T23:59:59.000Z

196

Two Experiments on Using a Scintillometer to Infer the Surface Fluxes of Momentum and Sensible Heat  

Science Conference Proceedings (OSTI)

A traditional use of scintillometry is to infer path-averaged values of the turbulent surface fluxes of sensible heat Hs and momentum ? (, where ? is air density and u* is the friction velocity). Many scintillometer setups, however, measure only ...

Edgar L Andreas

2012-09-01T23:59:59.000Z

197

Parameterization of Surface Heat Fluxes above Forest with Satellite Thermal Sensing and Boundary-Layer Soundings  

Science Conference Proceedings (OSTI)

Satellite-derived surface temperature measurements can be used in conjunction with temperature and wind soundings in the boundary layer to determine the surface sensible heat flux from forests at the regional scale. The underlying formulation is ...

Wilfried Brutsaert; A. Y. Hsu; Thomas J. Schmugge

1993-05-01T23:59:59.000Z

198

Inverse Analysis Adjustment of the SOC Air–Sea Flux Climatology Using Ocean Heat Transport Constraints  

Science Conference Proceedings (OSTI)

Results are presented from a linear inverse analysis of the Southampton Oceanography Centre (SOC) air–sea flux climatology using 10 hydrographic ocean heat transport constraints distributed throughout the Atlantic and North Pacific Oceans. A ...

Jeremy P. Grist; Simon A. Josey

2003-10-01T23:59:59.000Z

199

Estimates of Surface Heat Flux from Sodar and Laser Scintillation Measurements in the Unstable Boundary Layer  

Science Conference Proceedings (OSTI)

Measurements of acoustic backscatter in the lower planetary boundary layer and optical line-of-sight scintillation in the surface layer are each used to compute sensible heat fluxes in the unstable surface layer. Comparisons with simultaneous low-...

R. L. Coulter; M. L. Wesely

1980-10-01T23:59:59.000Z

200

Heat and Momentum Fluxes Induced by Thermal Inhomogeneities with and without Large-Scale Flow  

Science Conference Proceedings (OSTI)

The authors Present an analytical evaluation of the vertical heat and momentum fluxes associated with mesoscale flow generated by periodic and isolated thermal inhomogeneities within the convective boundary layer (CBL). The influence of larger-...

G. A. Dalu; R. A. Pielke; M. Baldi; X. Zeng

1996-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

A Theory for the Statistical Equilibrium Energy Spectrum and Heat Flux Produced by Transient Baroclinic Waves  

Science Conference Proceedings (OSTI)

Obtaining a physically based understanding of the variations with spatial scale of the amplitude and dispersive properties of midlatitude transient baroclinic waves and the heat flux associated with these waves is a central goal of dynamic ...

Brian F. Farrell; Petros J. Ioannou

1994-10-01T23:59:59.000Z

202

The Annual Cycle of Meridional Heat Flux in the Atlantic Ocean at 26.5°N  

Science Conference Proceedings (OSTI)

Total meridional heat flux through a zonal oceanic section at 26.5°N in the Atlantic Ocean is computed from hydrographic, direct current and surface wind observations. The oceanic current and temperature fields are decomposed into depth-averaged ...

Robert L. Molinari; Elizabeth Johns; John F. Festa

1990-03-01T23:59:59.000Z

203

Estimation of Meridional Heat Flux in the North Atlantic by Inverse Methods  

Science Conference Proceedings (OSTI)

Hydrographic sections spanning the Atlantic Ocean at 24, 36 and 48°N are used to make an estimate of meridional heat flux in the ocean. An inverse method provides reference level velocities for geostrophic calculations, consistent with ...

Dean Roemmich

1980-12-01T23:59:59.000Z

204

Estimated Decadal Changes in the North Atlantic Meridional Overturning Circulation and Heat Flux 1993–2004  

Science Conference Proceedings (OSTI)

Results from a global 1° model constrained by least squares to a multiplicity of datasets over the interval 1992–2004 are used to describe apparent changes in the North Atlantic Ocean meridional overturning circulation and associated heat fluxes ...

Carl Wunsch; Patrick Heimbach

2006-11-01T23:59:59.000Z

205

Recent Variability of the North Atlantic Thermohaline Circulation Inferred from Surface Heat and Freshwater Fluxes  

Science Conference Proceedings (OSTI)

An annual-mean surface-forced component of the North Atlantic thermohaline circulation (THC) in density space, ?surf(?,?), is diagnosed from observed surface heat and freshwater fluxes. The climatological mean of ?surf over 1980–97 indicates ...

Robert Marsh

2000-09-01T23:59:59.000Z

206

Uncertainties in Global Ocean Surface Heat Flux Climatologies Derived from Ship Observations  

Science Conference Proceedings (OSTI)

A methodology to define uncertainties associated with ocean surface heat flux calculations has been developed and applied to a global climatology that utilizes a summary of the Comprehensive Ocean–Atmosphere Data Set surface observations. ...

Peter J. Gleckler; Bryan C. Weare

1997-11-01T23:59:59.000Z

207

Sensible Heat Flux in Near-Neutral Conditions over the Sea  

Science Conference Proceedings (OSTI)

The variation of the sea surface sensible heat flux is investigated using data from the Gulf of Tehuantepec Experiment (GOTEX) and from eight additional aircraft datasets representing a variety of surface conditions. This analysis focuses on near-...

L. Mahrt; Dean Vickers; Edgar L Andreas; Djamal Khelif

2012-07-01T23:59:59.000Z

208

Parameterizations of Sea-Spray Impact on the Air–Sea Momentum and Heat Fluxes  

Science Conference Proceedings (OSTI)

This paper focuses on parameterizing the effect of sea spray at hurricane-strength winds on the momentum and heat fluxes in weather prediction models using the Monin–Obukhov similarity theory (a common framework for the parameterizations of air–...

J.-W. Bao; C. W. Fairall; S. A. Michelson; L. Bianco

2011-12-01T23:59:59.000Z

209

Near-Surface Eddy Heat and Momentum Fluxes in the Antarctic Circumpolar Current in Drake Passage  

Science Conference Proceedings (OSTI)

The authors present new estimates of the eddy momentum and heat fluxes from repeated high-resolution upper-ocean velocity and temperature observations in Drake Passage and interpret their role in the regional Antarctic Circumpolar Current (ACC) ...

Yueng-Djern Lenn; Teresa K. Chereskin; Janet Sprintall; Julie L. McClean

2011-07-01T23:59:59.000Z

210

Two-Layer Baroclinic Eddy Heat Fluxes: Zonal Flows and Energy Balance  

Science Conference Proceedings (OSTI)

The eddy heat flux generated by statistically equilibrated baroclinic turbulence supported on a uniform, horizontal temperature gradient is examined using a two-layer ?-plane quasigeostrophic model. The dependence of the eddy diffusivity of ...

Andrew F. Thompson; William R. Young

2007-09-01T23:59:59.000Z

211

Sensible Heat Flux Estimation over the FIFE Site by Neural Networks  

Science Conference Proceedings (OSTI)

Observations from the First ISLSCP (International Satellite Land Surface Climatology Project) Field Experiment (FIFE) showed that it is difficult to estimate the sensible heat flux from routinely observed environmental parameters. This study, ...

Behzad Abareshi; Peter H. Schuepp

1998-04-01T23:59:59.000Z

212

Measurements of Turbulent Heat and Momentum Fluxes In a Mountain Valley  

Science Conference Proceedings (OSTI)

Measurements of heat and momentum fluxes along the valley floor of Brush Creek in Colorado are described. The measurements were taken in the fall of 1984 as part of the Department of Energy's Atmospheric Studies in Complex Terrain field program. ...

J. C. Doran; M. L. Wesely; R. T. McMillen; W. D. Neff

1989-06-01T23:59:59.000Z

213

Calculating Monthly Radiative Fluxes and Heating Rates fromMonthly Cloud Observations  

Science Conference Proceedings (OSTI)

The radiative transfer model from NCAR’s general circulation model CCM3 is modified to calculate monthly radiative fluxes and heating rates from monthly observations of cloud properties from the International Satellite Cloud Climatology Project ...

John W. Bergman; Harry H. Hendon

1998-12-01T23:59:59.000Z

214

Alumina Nanoparticle Pre-coated Tubing Ehancing Subcooled Flow Boiling Cricital Heat Flux  

E-Print Network (OSTI)

Nanofluids are engineered colloidal dispersions of nano-sized particle in common base fluids. Previous pool boiling studies have shown that nanofluids can improve critical heat flux (CHF) up to 200% for pool boiling and ...

Truong, Bao H.

215

Scintillometer-Based Estimates of Sensible Heat Flux Using Lidar-Derived Surface Roughness  

Science Conference Proceedings (OSTI)

The estimation of sensible heat flux, H, using large aperture scintillometer (LAS) under varying surface heterogeneity conditions was investigated. Surface roughness features characterized by variable topography and vegetation height were ...

Hatim M. E. Geli; Christopher M. U. Neale; Doyle Watts; John Osterberg; Henk A. R. De Bruin; Wim Kohsiek; Robert T. Pack; Lawrence E. Hipps

2012-08-01T23:59:59.000Z

216

Critical heat flux and boiling heat transfer to water in a 3-mm-diameter horizontal tube.  

DOE Green Energy (OSTI)

Boiling of the coolant in an engine, by design or by circumstance, is limited by the critical heat flux phenomenon. As a first step in providing relevant engine design information, this study experimentally addressed both rate of boiling heat transfer and conditions at the critical point of water in a horizontal tube of 2.98 mm inside diameter and 0.9144 m heated length. Experiments were performed at system pressure of 203 kPa, mass fluxes in range of 50 to 200 kg/m{sup z}s, and inlet temperatures in range of ambient to 80 C. Experimental results and comparisons with predictive correlations are presented.

Yu, W.; Wambsganss, M. W.; Hull, J. R.; France, D. M.

2000-12-04T23:59:59.000Z

217

Air–Sea Heat Flux Measurements from Nearly Neutrally Buoyant Floats  

Science Conference Proceedings (OSTI)

The ability of neutrally buoyant, high-drag floats to measure the air–sea heat flux from within the turbulent oceanic boundary layer is investigated using float data from four different winter and fall float deployments. Two flux estimates can be ...

Eric A. D'Asaro

2004-07-01T23:59:59.000Z

218

Influences of biomass heat and biochemical energy storages on the land surface fluxes and radiative temperature  

E-Print Network (OSTI)

Influences of biomass heat and biochemical energy storages on the land surface fluxes and radiative energy storages for land-atmosphere interactions, an issue that has been largely neglected so far. We the representation of biomass energy storages against measurements of surface energy and CO2 fluxes. We

219

Seasonal and Diurnal Fluxes of Radiation, Heat, Water Vapor, and Carbon Dioxide over a Suburban Area  

Science Conference Proceedings (OSTI)

Based on 1 yr of field measurements, the diurnal, seasonal, and annual fluxes of energy and carbon dioxide (CO2) at a residential area of Tokyo, Japan, are described. The major findings are as follows. 1) The storage heat flux G in the daytime ...

R. Moriwaki; M. Kanda

2004-11-01T23:59:59.000Z

220

Cloudiness and Marine Boundary Layer Dynamics in the ASTEX Lagrangian Experiments. Part II: Cloudiness, Drizzle, Surface Fluxes, and Entrainment  

Science Conference Proceedings (OSTI)

The Analysis of the Atlantic Stratocumulus Transition Experiment (ASTEX) Lagrangians started in Part I is continued, presenting measurements of sea surface temperature, surface latent and sensible heat fluxes from bulk aerodynamic formulas, cloud ...

Christopher S. Bretherton; Philip Austin; Steven T. Siems

1995-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Relationships among Remotely Sensed Data, Surface Energy Balance, and Area-Averaged Fluxes over Partially Vegetated Land Surfaces  

Science Conference Proceedings (OSTI)

Numerous recent field experiments have examined the use of remote sensing to estimate land surface fluxes of latent and sensible heat using combinations of thermal, visible, and near-infrared data. While substantial progress has been made, ...

M. A. Friedl

1996-11-01T23:59:59.000Z

222

Spatially resolved temperature and heat flux measurements for slow evaporating droplets heated by a microfabricated heater array  

E-Print Network (OSTI)

The evaporation phenomenon of a liquid droplet was investigated by using microfabricated heaters. All 32 microheaters were designed to have the same resistance. Gold microheaters worked both as temperature indicators and as heaters. The first experiment was performed under a constant voltage mode to investigate the temperature and heat flux variation of the heated surface by the evaporating droplet. The second experiment was performed under constant temperature mode to investigate the spatial and temporal heat flux variation of the constant temperature heater surface by the evaporating droplet heater. Droplet evaporation was recorded with a CCD camera. Experimental data showed temperature and heat flux variations inside and outside of the droplet with respect to time and radial position from the center of the droplet by tomographic deconvolution.

Paik, Sokwon

223

Solar passive ceiling system. Final report. [Passive solar heating system with venetian blind reflectors and latent heat storage in ceiling  

DOE Green Energy (OSTI)

The construction of a 1200 square foot building, with full basement, built to be used as a branch library in a rural area is described. The primary heating source is a passive solar system consisting of a south facing window system. The system consists of: a set of windows located in the south facing wall only, composed of double glazed units; a set of reflectors mounted in each window which reflects sunlight up to the ceiling (the reflectors are similar to venetian blinds); a storage area in the ceiling which absorbs the heat from the reflected sunlight and stores it in foil salt pouches laid in the ceiling; and an automated curtain which automatically covers and uncovers the south facing window system. The system is totally passive and uses no blowers, pumps or other active types of heat distribution equipment. The building contains a basement which is normally not heated, and the north facing wall is bermed four feet high around the north side.

Schneider, A.R.

1980-01-01T23:59:59.000Z

224

Thermal evaluation of uranium silicide miniplates irradiated at high heat flux  

Science Conference Proceedings (OSTI)

The Gas Test Loop (GTL)-1 irradiation experiment was conducted in the Advanced Test Reactor (ATR) to assess corrosion performance of proposed booster fuel at heat flux levels ~30% above the design operating condition. Sixteen miniplates fabricated from 25% enriched, high-density (4.8 g U/cm3) U3Si2/Al dispersion fuel with 6061 aluminum cladding were subjected to peak beginning of cycle (BOC) heat fluxes ranging from 411 to 593 W/cm2. No adverse impacts to the miniplates were observed at these high heat flux levels. A detailed finite element model was constructed to calculate temperatures and heat flux for an as-run cycle average effective ATR south lobe power of 25.4 MW(t). Miniplate heat flux levels and fuel, cladding, hydroxide, and coolant–hydroxide interface temperatures were calculated using the average hydroxide thickness on each miniplate measured during post-irradiation examination. The purpose of this study was to obtain a best estimate of the as-run experiment temperatures to aid in establishing acceptable heat flux levels and designing fuel qualification experiments for this fuel type.

Donna P. Guillen

2012-09-01T23:59:59.000Z

225

Calibration of High Heat Flux Sensors at NIST  

Science Conference Proceedings (OSTI)

... sides and uniform distri- bution of flow across the tube cross section, the ... is beneficial in minimizing the stagnation point flow heat transfer effects on ...

2012-10-18T23:59:59.000Z

226

Mass, Heat and Freshwater Fluxes in the South Indian Ocean  

Science Conference Proceedings (OSTI)

Six hydrographic sections were used to examine the circulation and property fluxes in the South Indian Ocean from 10° to 32°S. The calculations were made by applying an inverse method to the data. In the interior of the South Indian Ocean, the ...

Lee-Lueng Fu

1986-10-01T23:59:59.000Z

227

Uncertainty analysis of steady state incident heat flux measurements in hydrocarbon fuel fires.  

SciTech Connect

The objective of this report is to develop uncertainty estimates for three heat flux measurement techniques used for the measurement of incident heat flux in a combined radiative and convective environment. This is related to the measurement of heat flux to objects placed inside hydrocarbon fuel (diesel, JP-8 jet fuel) fires, which is very difficult to make accurately (e.g., less than 10%). Three methods will be discussed: a Schmidt-Boelter heat flux gage; a calorimeter and inverse heat conduction method; and a thin plate and energy balance method. Steady state uncertainties were estimated for two types of fires (i.e., calm wind and high winds) at three times (early in the fire, late in the fire, and at an intermediate time). Results showed a large uncertainty for all three methods. Typical uncertainties for a Schmidt-Boelter gage ranged from {+-}23% for high wind fires to {+-}39% for low wind fires. For the calorimeter/inverse method the uncertainties were {+-}25% to {+-}40%. The thin plate/energy balance method the uncertainties ranged from {+-}21% to {+-}42%. The 23-39% uncertainties for the Schmidt-Boelter gage are much larger than the quoted uncertainty for a radiative only environment (i.e ., {+-}3%). This large difference is due to the convective contribution and because the gage sensitivities to radiative and convective environments are not equal. All these values are larger than desired, which suggests the need for improvements in heat flux measurements in fires.

Nakos, James Thomas

2005-12-01T23:59:59.000Z

228

The sea spray contribution to sensible heat flux  

Science Conference Proceedings (OSTI)

Direct numerical simulations (DNS) of turbulent Couette flow are combined with Lagrangian point-particle tracking to investigate the effects of a dispersed phase on bulk passive heat transport when the two phases can exchange both momentum and ...

David H. Richter; Peter P. Sullivan

229

Remote Measurement of Heat Flux from Power Plant Cooling Lakes  

Science Conference Proceedings (OSTI)

Laboratory experiments have demonstrated a correlation between the rate of heat loss q? from an experimental fluid to the air above and the standard deviation ? of the thermal variability in images of the fluid surface. These experimental results ...

Alfred J. Garrett; Robert J. Kurzeja; Eliel Villa-Aleman; James S. Bollinger; Malcolm M. Pendergast

2013-06-01T23:59:59.000Z

230

Heat and Freshwater Fluxes through the Nordic Seas  

Science Conference Proceedings (OSTI)

The major exchanges of volume, heat, and freshwater between the Arctic Ocean and the World Ocean occur through the Nordic seas. Here is presented the northernmost estimate for the oceanic transport of these properties that is derived from a set ...

Kevin I. C. Oliver; Karen J. Heywood

2003-05-01T23:59:59.000Z

231

Saturated critical heat flux in a multi-microchannel heat sink fed by a split flow system  

SciTech Connect

An extensive experimental campaign has been carried out for the measurement of saturated critical heat flux in a multi-microchannel copper heat sink. The heat sink was formed by 29 parallel channels that were 199 {mu}m wide and 756 {mu}m deep. In order to increase the critical heat flux and reduce the two-phase pressure drop, a split flow system was implemented with one central inlet at the middle of the channels and two outlets at either end. The base critical heat flux was measured using three HFC Refrigerants (R134a, R236fa and R245fa) for mass fluxes ranging from 250 to 1500 kg/m{sup 2} s, inlet subcoolings from -25 to -5 K and saturation temperatures from 20 to 50 C. The parametric effects of mass velocity, saturation temperature and inlet subcooling were investigated. The analysis showed that significantly higher CHF was obtainable with the split flow system (one inlet-two outlets) compared to the single inlet-single outlet system, providing also a much lower pressure drop. Notably several existing predictive methods matched the experimental data quite well and quantitatively predicted the benefit of higher CHF of the split flow. (author)

Mauro, A.W.; Toto, D. [Department of Energetics, Applied Thermofluidynamics and Air Conditioning Systems, FEDERICO II University, p.le Tecchio 80, 80125 Napoli (Italy); Thome, J.R. [Laboratory of Heat and Mass Transfer (LTCM), Faculty of Engineering (STI), Ecole Polytechnique Federale de Lausanne (EPFL), Station 9, Lausanne CH-1015 (Switzerland); Vanoli, G.P. [Engineering Department, Sannio University, Corso Garibaldi 107, Palazzo dell'Aquila Bosco Lucarelli, 82100 Benevento (Italy)

2010-01-15T23:59:59.000Z

232

Simulation of tokamak SOL and divertor region including heat flux mitigation by gas puffing  

Science Conference Proceedings (OSTI)

Two-dimensional (2D), scrape-off layer (SOL)-divertor transport simulations are performed using the integrated plasma-neutral-impurity code KTRAN developed at Seoul National University. Firstly, the code is applied to reproduce a National Spherical Torus eXperiment (NSTX) discharge by using the prescribed transport coefficients and the boundary conditions obtained from the experiment. The plasma density, the heat flux on the divertor plate, and the D (alpha) emission rate profiles from the numerical simulation are found to follow experimental trends qualitatively. Secondly, predictive simulations are carried out for the baseline operation mode in Korea Superconducting Tokamak Advanced Research (KSTAR) to predict the heat flux on the divertor target plates. The stationary peak heat flux in the KSTAR baseline operation mode is expected to be 6.5 MW/m(2) in the case of an orthogonal divertor. To study the mitigation of the heat flux, we investigated the puffing effects of deuterium and argon gases. The puffing position is assumed to be in front of the strike point at the outer lower divertor plate. In the simulations, mitigation of the peak heat flux at the divertor target plates is found to occur when the gas puffing rate exceeds certain values, similar to 1.0 x 10(20) /s and similar to 5.0 x 10(18) /s for deuterium and argon, respectively. Multi-charged impurity transport is also investigated for both NSTX and KSTAR SOL and divertor regions.

Park, Jin Woo [Seoul National University, Seoul, S. Korea; Na, Y. S. [Seoul National University, Seoul, S. Korea; Hong, S. H. [National Fusion Research Institute, Daejon, South Korea; Ahn, J.W. [Oak Ridge National Laboratory (ORNL); Kim, D. K. [Agency Def Dev, Taejon, South Korea; Han, Hyunsun [National Fusion Research Institute, Taejon, South Korea; Shim, Seong Bo [Pusan National University, Busan, Korea; Lee, Hae June [Pusan National University, Busan, Korea

2012-01-01T23:59:59.000Z

233

Contributions from California Coastal-Zone Surface Fluxes to Heavy Coastal Precipitation: A CALJET Case Study during the Strong El Niño of 1998  

Science Conference Proceedings (OSTI)

Analysis of the case of 3 February 1998, using an extensive observational system in the California Bight during an El Niño winter, has revealed that surface sensible and latent heat fluxes within 150 km of the shore contributed substantially to ...

P. Ola G. Persson; P. J. Neiman; B. Walter; J-W. Bao; F. M. Ralph

2005-05-01T23:59:59.000Z

234

Evaluation of the Noah Land Surface Model Using Data from a Fair-Weather IHOP_2002 Day with Heterogeneous Surface Fluxes  

Science Conference Proceedings (OSTI)

Sources of differences between observations and simulations for a case study using the Noah land surface model–based High-Resolution Land Data Assimilation System (HRLDAS) are examined for sensible and latent heat fluxes H and LE, respectively; ...

Margaret A. LeMone; Mukul Tewari; Fei Chen; Joseph G. Alfieri; Dev Niyogi

2008-12-01T23:59:59.000Z

235

Role of Net Surface Heat Flux in Seasonal Variations of Sea Surface Temperature in the Tropical Atlantic Ocean  

Science Conference Proceedings (OSTI)

The present study used a new net surface heat flux (Qnet) product obtained from the Objective Analyzed Air–Sea Fluxes (OAFlux) project and the International Satellite Cloud Climatology Project (ISCCP) to examine two specific issues—one is to ...

Lisan Yu; Xiangze Jin; Robert A. Weller

2006-12-01T23:59:59.000Z

236

Heat Flux Electrochemical Studies of Underdeposit Boiler Tube Corrosion  

Science Conference Proceedings (OSTI)

Boiler water-side corrosion in fossil plants represents a key cause of availability loss and performance degradation, with underdeposit corrosion (UDC) being a major damage mechanism. UDC results from concentration of impurities and contaminants within the structure of the deposit residing on the heated internal surfaces of boiler waterwall tubing. The EPRI cycle chemistry guidelines provide control curves based on ...

2013-09-10T23:59:59.000Z

237

Recent High Heat Flux Tests on W-Rod-Armored Mockups  

Science Conference Proceedings (OSTI)

In the authors initial high heat flux tests on small mockups armored with W rods, done in the small electron beam facility (EBTS) at Sandia National Laboratories, the mockups exhibited excellent thermal performance. However, to reach high heat fluxes, they reduced the heated area to only a portion ({approximately}25%) of the sample. They have now begun tests in their larger electron beam facility, EB 1200, where the available power (1.2 MW) is more than enough to heat the entire surface area of the small mockups. The initial results indicate that, at a given power, the surface temperatures of rods in the EB 1200 tests is somewhat higher than was observed in the EBTS tests. Also, it appears that one mockup (PW-10) has higher surface temperatures than other mockups with similar height (10mm) W rods, and that the previously reported values of absorbed heat flux on this mockup were too high. In the tests in EB 1200 of a second mockup, PW-4, absorbed heat fluxes of {approximately}22MW/m{sup 2} were reached but the corresponding surface temperatures were somewhat higher than in EBTS. A further conclusion is that the simple 1-D model initially used in evaluating some of the results from the EBTS testing was not adequate, and 3-D thermal modeling will be needed to interpret the results.

NYGREN,RICHARD E.; YOUCHISON,DENNIS L.; MCDONALD,JIMMIE M.; LUTZ,THOMAS J.; MISZKIEL,MARK E.

2000-07-18T23:59:59.000Z

238

Correcting eddy-covariance flux underestimates over a grassland.  

Science Conference Proceedings (OSTI)

Independent measurements of the major energy balance flux components are not often consistent with the principle of conservation of energy. This is referred to as a lack of closure of the surface energy balance. Most results in the literature have shown the sum of sensible and latent heat fluxes measured by eddy covariance to be less than the difference between net radiation and soil heat fluxes. This under-measurement of sensible and latent heat fluxes by eddy-covariance instruments has occurred in numerous field experiments and among many different manufacturers of instruments. Four eddy-covariance systems consisting of the same models of instruments were set up side-by-side during the Southern Great Plains 1997 Hydrology Experiment and all systems under-measured fluxes by similar amounts. One of these eddy-covariance systems was collocated with three other types of eddy-covariance systems at different sites; all of these systems under-measured the sensible and latent-heat fluxes. The net radiometers and soil heat flux plates used in conjunction with the eddy-covariance systems were calibrated independently and measurements of net radiation and soil heat flux showed little scatter for various sites. The 10% absolute uncertainty in available energy measurements was considerably smaller than the systematic closure problem in the surface energy budget, which varied from 10 to 30%. When available-energy measurement errors are known and modest, eddy-covariance measurements of sensible and latent heat fluxes should be adjusted for closure. Although the preferred method of energy balance closure is to maintain the Bowen-ratio, the method for obtaining closure appears to be less important than assuring that eddy-covariance measurements are consistent with conservation of energy. Based on numerous measurements over a sorghum canopy, carbon dioxide fluxes, which are measured by eddy covariance, are underestimated by the same factor as eddy covariance evaporation measurements when energy balance closure is not achieved.

Twine, T. E.; Kustas, W. P.; Norman, J. M.; Cook, D. R.; Houser, P. R.; Meyers, T. P.; Prueger, J. H.; Starks, P. J.; Wesely, M. L.; Environmental Research; Univ. of Wisconsin at Madison; DOE; National Aeronautics and Space Administration; National Oceanic and Atmospheric Administrationoratory

2000-06-08T23:59:59.000Z

239

Using remotely sensed planetary boundary layer variables as estimates of areally averaged heat flux  

SciTech Connect

Homogeneity across the Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site is an issue of importance to all facets of the Atmospheric Radiation Measurements (ARM) program. The degree to which measurements at the central facility can be used to verify, improve, or develop relationships in radiative flux models that are subsequently used in Global Circulation Models (GCMs), for example, is tied directly to the representativeness of the local measurements at the central facility for the site as a whole. The relative variation of surface energy budget terms over a 350- km X 400km domain such as the SGP CART site can be extremely large. The Planetary Boundary Layer (PBL) develops as a result of energy inputs from widely varying surfaces. The lower atmosphere effectively integrates the local inputs; measurements of PBL structure can potentially be used for estimates of surface heat flux over scales on the order of tens of kilometers. This project is focusing on two PBL quantities that are intimately tied to the surface heat flux: (1) the height of the mixed layer, z, that grows during daytime due to sensible heat flux input from the surface; and (2) the convective velocity scale, normally a scaling parameter defined by the product of the sensible heat flux and z, but in this case defined by coherent structures that connect the surface layer and the capping inversion that defines z.

Coulter, R.L.; Martin, T.J.; Holdridge, D.J.

1995-06-01T23:59:59.000Z

240

Method and apparatus for determining vertical heat flux of geothermal field  

DOE Patents (OSTI)

A method and apparatus for determining vertical heat flux of a geothermal field, and mapping the entire field, is based upon an elongated heat-flux transducer (10) comprised of a length of tubing (12) of relatively low thermal conductivity with a thermopile (20) inside for measuring the thermal gradient between the ends of the transducer after it has been positioned in a borehole for a period sufficient for the tube to reach thermal equilibrium. The transducer is thermally coupled to the surrounding earth by a fluid annulus, preferably water or mud. A second transducer comprised of a length of tubing of relatively high thermal conductivity is used for a second thermal gradient measurement. The ratio of the first measurement to the second is then used to determine the earth's thermal conductivity, k.sub..infin., from a precalculated graph, and using the value of thermal conductivity thus determined, then determining the vertical earth temperature gradient, b, from predetermined steady state heat balance equations which relate the undisturbed vertical earth temperature distributions at some distance from the borehole and earth thermal conductivity to the temperature gradients in the transducers and their thermal conductivity. The product of the earth's thermal conductivity, k.sub..infin., and the earth's undisturbed vertical temperature gradient, b, then determines the earth's vertical heat flux. The process can be repeated many times for boreholes of a geothermal field to map vertical heat flux.

Poppendiek, Heinz F. (LaJolla, CA)

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Separate effects of surface roughness, wettability and porosity on boiling heat transfer and critical heat flux and optimization of boiling surfaces  

E-Print Network (OSTI)

The separate effects of surface wettability, porosity, and roughness on critical heat flux (CHF) and heat transfer coefficient (HTC) were examined using carefully-engineered surfaces. All test surfaces were prepared on ...

O'Hanley, Harrison Fagan

2012-01-01T23:59:59.000Z

242

Review of current status of high flux heat transfer techniques. Volume I. Text + Appendix A  

SciTech Connect

The scope of this work comprised two tasks. The first was to review high heat flux technology with consideration given to heat transfer panel configuration, diagnostics techniques and coolant supply. The second task was to prepare a report describing the findings of the review, to recommend the technology offering the least uncertainty for scale-up for the MFTF-B requirement and to recommend any new or perceived requirements for R and D effort.

Bauer, W.H.; Gordon, H.S.; Lackner, H.; Mettling, J.R.; Miller, J.E.

1980-09-01T23:59:59.000Z

243

Eddy Correlation Flux Measurement System (ECOR) Handbook  

SciTech Connect

The eddy correlation (ECOR) flux measurement system provides in situ, half-hour measurements of the surface turbulent fluxes of momentum, sensible heat, latent heat, and carbon dioxide (CO2) (and methane at one Southern Great Plains extended facility (SGP EF) and the North Slope of Alaska Central Facility (NSA CF). The fluxes are obtained with the eddy covariance technique, which involves correlation of the vertical wind component with the horizontal wind component, the air temperature, the water vapor density, and the CO2 concentration.

Cook, DR

2011-01-31T23:59:59.000Z

244

Onset of dry-wall heat transfer in low-mass-flux spray cooling  

SciTech Connect

This paper reports on an experimental investigation that was performed to study a low-mass-flux, spray nucleate boiling phenomenon termed dry wall during which all the impinging liquid is immediately vaporized upon contact with the heated surface. Measurements of wall heat flux and spray coolant mass flux were performed together with a characterization of spray parameters (such as local droplet size and velocity), using a laser-based diagnostic technique. Two different atomizing nozzles were used, and the effect of liquid subcooling on the transition was also studied. The transition to the dry-wall heat transfer regime was found to correlate well with the average global concentration of the spray obtained by the ratio of the spray mass flux to the average global concentration of the spray obtained by the ratio of the spray mass flux to the average spray velocity. The experimental results showed that above a concentration of approximately 0.20 kg/m{sup 3}, no evidence was seen of transition to dry wall. This concentration corresponding to transition was found to be independent of the two different nozzle types used in this study.

Webb, B.W.; Queiroz, M.; Oliphant, K.N.; Bonin, M.P. (Brigham Young Univ., Provo, UT (US))

1992-01-01T23:59:59.000Z

245

Continuous Time Series of Catchment-Averaged Sensible Heat Flux from a Large Aperture Scintillometer: Efficient Estimation of Stability Conditions and Importance of Fluxes under Stable Conditions  

Science Conference Proceedings (OSTI)

A large aperture scintillometer (LAS) observes the intensity of the atmospheric turbulence across large distances, which is related to the path-averaged sensible heat flux H. In this paper, two problems in the derivation of continuous series of H ...

Bruno Samain; Willem Defloor; Valentijn R. N. Pauwels

2012-04-01T23:59:59.000Z

246

A Variational Method for Computation of Sensible Heat Flux over the Arctic Sea Ice  

Science Conference Proceedings (OSTI)

In this study, a variational approach was employed to compute surface sensible heat flux over the Arctic sea ice. Because the variational approach is able to take into account information from the Monin–Obukhov similarity theory (MOST) as well as ...

Zuohao Cao; Jianmin Ma

2009-04-01T23:59:59.000Z

247

Precipitation Sensitivity to Surface Heat Fluxes over North America in Reanalysis and Model Data  

Science Conference Proceedings (OSTI)

A new methodology for assessing the impact of surface heat fluxes on precipitation is applied to data from the North American Regional Reanalysis (NARR) and to output from the Geophysical Fluid Dynamics Laboratory’s Atmospheric Model 2.1 (AM2.1). ...

Alexis Berg; Kirsten Findell; Benjamin R. Lintner; Pierre Gentine; Christopher Kerr

2013-06-01T23:59:59.000Z

248

Influence of leaf area index prescriptions on simulations of heat, moisture, and carbon fluxes  

Science Conference Proceedings (OSTI)

Leaf-area index (LAI), the total one-sided surface area of leaf per ground surface area, is a key component of land surface models. We investigate the influence of differing, plausible LAI prescriptions on heat, moisture, and carbon fluxes ...

Jatin Kala; Mark Decker; Jean-François Exbrayat; Andy J. Pitman; Claire Carouge; Jason P. Evans; Gab Abramowitz; David Mocko

249

The Simulation of Surface Heat Fluxes in a Land Surface?Atmosphere Model  

Science Conference Proceedings (OSTI)

A modified soil-canopy-boundary layer model based on Ek and Mahrt is presented to simulate surface heat fluxes on a daily basis. The model is validated against independent published bare soil data from Agassiz, Canada, and observations taken over ...

Huang Xinmei; T. J. Lyons

1995-05-01T23:59:59.000Z

250

Surface Heat Flux in the East China Sea and the Yellow Sea  

Science Conference Proceedings (OSTI)

Climatological monthly mean variations of the surface heat fluxes over the East China Sea and the Yellow Sea are calculated by both a data analysis and a numerical simulation. The result of the data analysis based on the empirical/bulk method ...

Naoki Hirose; Hyun-Chul Lee; Jong-Hwan Yoon

1999-03-01T23:59:59.000Z

251

Volume, Freshwater, and Heat Fluxes through Davis Strait, 2004–05  

Science Conference Proceedings (OSTI)

Davis Strait volume [?2.3 ± 0.7 Sv (1 Sv ? 106 m3 s?1); negative sign indicates southward transport], freshwater (?116 ± 41 mSv), and heat (20 ± 9 TW) fluxes estimated from objectively mapped 2004–05 moored array data do not differ significantly ...

B. Curry; C. M. Lee; B. Petrie

2011-03-01T23:59:59.000Z

252

A Simple Atmospheric Model of Surface Heat Flux for Use in Ocean Modeling Studies  

Science Conference Proceedings (OSTI)

A simple model of the lower atmospheric layers and land/sea ice surface is described and analyzed. The model is able to depict with reasonable accuracy the global ocean heat fluxes. Due to the model's simplicity, insight into the mechanisms ...

Richard Kleeman; Scott B. Power

1995-01-01T23:59:59.000Z

253

Computation of Ground Surface Conduction Heat Flux by Fourier Analysis of Surface Temperature  

Science Conference Proceedings (OSTI)

A method for computing the ground surface heat flux density is tested at two places in West Africa during the rainy season and during the dry season. This method is based upon the Fourier analysis of the experimental ground surface temperature. ...

Guy Cautenet; Michel Legrand; Yaya Coulibaly; Christian Boutin

1986-03-01T23:59:59.000Z

254

Wind Stress and Heat Flux over the Ocean in Gale Force Winds  

Science Conference Proceedings (OSTI)

An offshore stable platform has been instrumented with wind turbulence, temperature and wave height sensors. Data from this platform have been analyzed by the eddy correlation method to obtain wind stress and heat flux at wind speeds from 6 to 22 ...

Stuart D. Smith

1980-05-01T23:59:59.000Z

255

The deterioration in heat transfer to fluids at supercritical pressure and high heat fluxes  

E-Print Network (OSTI)

At slightly supercritical pressure and in the neighborhood of the pseudo-critical temperature (defined as the temperature corresponding to the peak in specific heat at the operating pressure), the heat transfer coefficient ...

Shiralkar, B. S.

1968-01-01T23:59:59.000Z

256

Heat transfer to impacting drops and post critical heat flux dispersed flow  

E-Print Network (OSTI)

Heat transfer to drops impacting on a hot surface is examined in context of dispersions of flowing, boiling fluids. The liquid contribution to heat transfer from a hot tube to a two-phase dispersion is formulated in terms ...

Kendall, Gail E.

1978-01-01T23:59:59.000Z

257

Estimates of Evapotranspiration with a One- and Two-Layer Model of Heat Transfer over Partial Canopy Cover  

Science Conference Proceedings (OSTI)

One of the applications of remotely sensed surface temperature is to determine the latent heat flux (LE) or evapotranspiration (ET) from held to regional scales. A common approach has been to use surface-air temperature differences in a bulk ...

William P. Kustas

1990-08-01T23:59:59.000Z

258

A Bulk Turbulent Air–Sea Flux Algorithm for High-Wind, Spray Conditions  

Science Conference Proceedings (OSTI)

Sensible and latent heat can cross the air–sea interface by two routes: as interfacial fluxes controlled by molecular processes right at the interface, and as spray fluxes from the surface of sea spray droplets. Once the 10-m wind speed over the ...

Edgar L. Andreas; P. Ola G. Persson; Jeffrey E. Hare

2008-07-01T23:59:59.000Z

259

Heat Capacity and Latent Heat The objective of this laboratory is for you to explore the heat capacity of materials due to atomic  

E-Print Network (OSTI)

, dataacquisition software, plotting and analysis software Introduction Knowledge of the heat capacity of graphite, SIC, paraffin, Bi, stearic acid, MgCl26H2O · DSC Al cans and press for loading · Computer rate change the results? Do some materials or loading methods give more accurate results than

Braun, Paul

260

Interactions Between the Daytime Mixed Layer and the Surface: Oklahoma Mesonet and EBBR Heat Fluxes  

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

Interactions Between the Daytime Mixed Layer Interactions Between the Daytime Mixed Layer and the Surface: Oklahoma Mesonet and EBBR Heat Fluxes R. L. Coulter Argonne National Laboratory Argonne, Illinois Introduction Surface layer estimates of surface sensible heat flux have been made at 10 - 14 locations within the Central Facility (CF) of the Southern Great Plains (SGP) Atmospheric Radiation Measurement (ARM) Program site by using energy balance Bowen ratio (EBBR) stations located mostly in uncultivated areas. The advent of the Oklahoma Mesonet (OKM) with approximately 50 stations within the boundaries of the Cloud and Radiation Testbed (CART) site that measure a variety of meteorological parameters leads to the possibility of using the OKM to provide additional estimates of surface energy budget to augment

Note: This page contains sample records for the topic "flux latent heat" 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

Solar-receiver heat-flux capability and structural integrity. Final report  

DOE Green Energy (OSTI)

An experimental program was conducted to determine the operating characteristics of full length (65 feet) single and multi-tube once-through steam generator test sections subjected to radiant heat flux levels commensurate with commercial solar tower receiver application. Absorbed heat flux levels ranging from 0.15 to 0.71 Btu/in./sup 2/-sec (0.25 to 1.16 MW/m/sup 2/) were achieved in a horizontal facility utilizing graphite radiant heater arrays. Steam exit temperatures ranged from 625 F (two-phase) to 1380 F at pressures of 1000 to 2300 psia. Wall temperature profiles and fluid pressure losses were obtained and compared with an existing computer model.

Tobin, R.D.

1976-05-01T23:59:59.000Z

262

Simplified model for determining local heat flux boundary conditions for slagging wall  

SciTech Connect

In this work, two models for calculating heat transfer through a cooled vertical wall covered with a running slag layer are investigated. The first one relies on a discretization of the velocity equation, and the second one relies on an analytical solution. The aim is to find a model that can be used for calculating local heat flux boundary conditions in computational fluid dynamics (CFD) analysis of such processes. Two different cases where molten deposits exist are investigated: the black liquor recovery boiler and the coal gasifier. The results show that a model relying on discretization of the velocity equation is more flexible in handling different temperature-viscosity relations. Nevertheless, a model relying on an analytical solution is the one fast enough for a potential use as a CFD submodel. Furthermore, the influence of simplifications to the heat balance in the model is investigated. It is found that simplification of the heat balance can be applied when the radiation heat flux is dominant in the balance. 9 refs., 7 figs., 10 tabs.

Bingzhi Li; Anders Brink; Mikko Hupa [Aabo Akademi University, Turku (Finland). Process Chemistry Centre

2009-07-15T23:59:59.000Z

263

Ultrahigh heat flux plasma-facing components for magnetic fusion energy  

Science Conference Proceedings (OSTI)

Sandia and Ultramet partnered to design and test refractory metal plasma-facing components and heat exchangers for advanced, high-temperature power conversion systems. These devices consisted of high-temperature helium-to-helium and lithium-to-helium heat exchangers that operate with high efficiency due to the porous foam inserts used in the gas stream, which promote turbulence and provide extended surface area for enhanced convection. Single- and multi-channel helium panels and the Li-He heat exchanger were fabricated from either pure molybdenum, TZM, or tungsten. The design was carried out through an Ultramet subcontractor. The flow path was carefully tailored to minimize the pressure drop while maximizing the heat transfer. The single- and multi-channel helium panels were tested at Sandia's PMTF using an electron beam system and the closed helium flow loop. In 2006, a single-channel tungsten tube was successfully tested to an average heat flux of 14 MW/m{sup 2} with a localized peak of 22 MW/m{sup 2} along the axial centerline at the outer radius. Under this CRADA, multiple square-channel molybdenum components were successfully tested to heat flux levels approaching 8.5 MW/m{sup 2}. The three multi-channel prototypes experienced mechanical failure due to issues related to the design of the large unsupported span of the heated faceplates in combination with prototype material and braze selection. The Li-He heat exchanger was both designed and partially tested at the PMTF for helium and lithium flow.

Youchison, D. L.

2012-03-01T23:59:59.000Z

264

Towards CFD Modelling of Critical Heat Flux in Fuel Rod Bundles  

SciTech Connect

The paper describes actual CFD approaches to subcooled boiling and investigates their capability to contribute to fuel assembly design. In a prototype version of the CFD code CFX a wall boiling model is implemented based on a wall heat flux partition algorithm. It can be shown, that the wall boiling model is able, to calculate the cross sectional averaged vapour volume fraction with good agreement to published measurements. The most sensitive parameters of the model are identified. Needs for more detailed experiments are established which are necessary to support further model development. Nevertheless in the paper the model is applied for the investigation of the phenomena inside a hot channel in a fuel assembly. Here the essential parameter is the critical heat flux. Although subcooled boiling represents only a preliminary state toward critical heat flux essential parameters like the swirl, the cross flow between adjacent channels and concentration regions of bubbles can be determined. By calculating the temperature at the rod surface the critical regions can be identified which might later on lead to departure from nucleate boiling and possible damage of the fuel pin. The application of up-to-date CFD with a subcooled boiling model for the simulation of a hot channel enables the comparison and the evaluation of different geometrical designs of the spacer grids of a fuel rod bundle. (authors)

Krepper, Eckhard [Forschungszentrum Rossendorf e.V., Institute of Safety Research, D-01314 Dresden, POB 510119 (Germany); Egorov, Yury [ANSYS Germany GmbH Staudenfeldweg 12, D-83624 Otterfing (Germany); Koncar, Bostjan ['Jozef Stefan' Institute Jamova 39, 1000 Ljubljana (Slovenia)

2006-07-01T23:59:59.000Z

265

Estimating Air–Sea Heat Fluxes in Semienclosed Basins: The Case of the Gulf of Elat (Aqaba)  

Science Conference Proceedings (OSTI)

Meteorological and oceanographic data collected at the head of the Gulf of Elat were used to compute the air–sea heat flux components and the heat storage in the water column, which are in turn used to estimate the heat balance of this ...

Moshe Ben-Sasson; Steve Brenner; Nathan Paldor

2009-01-01T23:59:59.000Z

266

Comparison between Nimbus-7 SMMR and ECMWF Model Analyses: The Problem of the Surface Latent Heat Flux  

Science Conference Proceedings (OSTI)

Nimbus-7 SMMR data of sea surface temperature, surface wind and precipitable water are compared to the ECMWF model daily analyzes for the first Special Observing Period of the FGGE Period (January-February 1979). The comparison of these fields ...

L. Eymard; C. Klapisz; R. Bernard

1989-12-01T23:59:59.000Z

267

Regional CO2 and latent heat surface fluxes in the Southern Great Plains: Measurements, modeling, and scaling  

E-Print Network (OSTI)

a mixed forest from tall tower mixing ratio measurements,vapor measurements from a tall tower, Journal of Geophysical

Riley, W. J.

2010-01-01T23:59:59.000Z

268

Sensitivity of Latent Heat Flux from PILPS Land-Surface Schemes to Perturbations of Surface Air Temperature  

Science Conference Proceedings (OSTI)

In the PILPS Phase 2a experiment, 23 land-surface schemes were compared in an off-line control experiment using observed meteorological data from Cabauw, the Netherlands. Two simple sensitivity experiments were also undertaken in which the ...

Weiqing Qu; A. Henderson-Sellers; A. J. Pitman; T. H. Chen; F. Abramopoulos; A. Boone; S. Chang; F. Chen; Y. Dai; R. E. Dickinson; L. Dümenil; M. Ek; N. Gedney; Y. M. Gusev; J. Kim; R. Koster; E. A. Kowalczyk; J. Lean; D. Lettenmaier; X. Liang; J.-F. Mahfouf; H.-T. Mengelkamp; K. Mitchell; O. N. Nasonova; J. Noilhan; A. Robock; C. Rosenzweig; J. Schaake; C. A. Schlosser; J.-P. Schulz; A. B. Shmakin; D. L. Verseghy; P. Wetzel; E. F. Wood; Z.-L. Yang; Q. Zeng

1998-06-01T23:59:59.000Z

269

Trend Singular Value Decomposition Analysis and Its Application to the Global Ocean Surface Latent Heat Flux and SST Anomalies  

Science Conference Proceedings (OSTI)

Given the complexity of trends in the actual climate system, distinguishing between different trends and different trend modes is important for climate research. This study introduces a new method called “trend singular value decomposition (TSVD) ...

Gen Li; Baohua Ren; Jianqiu Zheng; Chengyun Yang

2011-06-01T23:59:59.000Z

270

Elementary Heating Events - Magnetic Interactions Between Two Flux Sources. III Energy Considerations  

E-Print Network (OSTI)

The magnetic field plays a crucial role in heating the solar corona, but the exact energy release mechanism(s) is(are) still unknown. Here, we investigate in detail, the process of magnetic energy release in a situation where two initially independent flux systems are forced into each other. Work done by the foot point motions goes in to building a current sheet in which magnetic reconnection takes place. The scaling relations of the energy input and output are determined as functions of the driving velocity and the strength of fluxes in the independent flux systems. In particular, it is found that the energy injected into the system is proportional to the distance travelled not the rate of travel. Similarly, the rate of Joule dissipation is related to the distance travelled. Hence, rapidly driven foot points lead to bright, intense, but short-lived events, whilst slowly driven foot points produce weaker, but longer-lived brightenings. Integrated over the lifetime of the events both would produce the same heating if all other factors were the same. A strong overlying field has the affect of creating compact flux lobes from the sources. These appear to lead to a more rapid injection of energy, as well as a more rapid release of energy. Thus, the stronger the overlying field the more compact and more intense the heating. This means observers must know the rate of movement of the magnetic fragments involved in an events, as well as determine the strength and orientation of the surrounding field to be able to predict anything about the energy dissipated.

K. Galsgaard; C. E. Parnell

2005-01-27T23:59:59.000Z

271

New Insights into the Ocean Heat Budget Closure Problem from Analysis of the SOC Air–Sea Flux Climatology  

Science Conference Proceedings (OSTI)

Results from an analysis of the Southampton Oceanography Centre (SOC) global air–sea heat flux climatology, which has been calculated using in situ weather reports from voluntary observing ships covering the period 1980–93, are presented. ...

Simon A. Josey; Elizabeth C. Kent; Peter K. Taylor

1999-09-01T23:59:59.000Z

272

Turbulent Heat Fluxes in Urban Areas: Observations and a Local-Scale Urban Meteorological Parameterization Scheme (LUMPS)  

Science Conference Proceedings (OSTI)

A linked set of simple equations specifically designed to calculate heat fluxes for the urban environment is presented. This local-scale urban meteorological parameterization scheme (LUMPS), which has similarities to the hybrid plume dispersion ...

C. S. B. Grimmond; T. R. Oke

2002-07-01T23:59:59.000Z

273

Commissioning of the Korean High Heat Flux Test Facility by Using Electron Beam System for Plasma Facing Components  

Science Conference Proceedings (OSTI)

Divertor and High-Heat-Flux Components / Proceedings of the Twentieth Topical Meeting on the Technology of Fusion Energy (TOFE-2012) (Part 1), Nashville, Tennessee, August 27-31, 2012

Suk-Kwon Kim; Eo Hwak Lee; Jae-Sung Yoon; Dong Won Lee; Duck-Hoi Kim; Seungyon Cho

274

Seasonal and Low-Frequency Variability of the Meridional Heat Flux at 36°N in the North Atlantic  

Science Conference Proceedings (OSTI)

Historical hydrographic sections are used to investigate the seasonal and interannual variability in the meridional heat flux at 36°N in the North Atlantic. The data consist of ten transatlantic sections and sections from four sectors, which ...

Olga T. Sato; T. Rossby

2000-03-01T23:59:59.000Z

275

Northern Hemisphere Winter Atmospheric Transient Eddy Heat Fluxes and the Gulf Stream and Kuroshio-Oyashio Extension Variability  

Science Conference Proceedings (OSTI)

Spatial and temporal co-variability between the atmospheric transient eddy heat fluxes (i.e. and ) in the Northern Hemisphere winter (January-March) and the paths of the Gulf Stream (GS), Kuroshio Extension (KE), and Oyashio Extension ...

Young-Oh Kwon; Terrence M. Joyce

276

Divergent Eddy Heat Fluxes in the Kuroshio Extension at 144°–148°E. Part II: Spatiotemporal Variability  

Science Conference Proceedings (OSTI)

The Kuroshio Extension System Study (KESS) provided 16 months of observations to quantify divergent eddy heat flux (DEHF) from a mesoscale-resolving array of current- and pressure-equipped inverted echo sounders. KESS observations captured a ...

Stuart P. Bishop

2013-11-01T23:59:59.000Z

277

Divergent Eddy Heat Fluxes in the Kuroshio Extension at 144°–148°E. Part I: Mean Structure  

Science Conference Proceedings (OSTI)

The Kuroshio Extension System Study (KESS) provided 16 months of observations to quantify eddy heat flux (EHF) from a mesoscale-resolving array of current- and pressure-equipped inverted echo sounders (CPIES). The mapped EHF estimates agreed well ...

Stuart P. Bishop; D. Randolph Watts; Kathleen A. Donohue

2013-08-01T23:59:59.000Z

278

Eddy Heat Flux Convergence in the Troposphere and Its Effect on the Meridional Circulation and Ozone Distribution  

Science Conference Proceedings (OSTI)

In this study the vertical convergence of the eddy heat flux, found as a forcing term in the thermodynamic energy equation of the transformed Eulerian mean formulation, is estimated in the troposphere and in the lower stratosphere from ...

Wookap Choi; Douglas A. Rotman; Donald J. Wuebbles

1995-12-01T23:59:59.000Z

279

Investigation of downward facing critical heat flux with water-based nanofluids for In-Vessel Retention applications  

E-Print Network (OSTI)

In-Vessel Retention ("IVR") is a severe accident management strategy that is power limiting to the Westinghouse AP1000 due to critical heat flux ("CHF") at the outer surface of the reactor vessel. Increasing the CHF level ...

DeWitt, Gregory L

2011-01-01T23:59:59.000Z

280

Northern Hemisphere Winter Atmospheric Transient Eddy Heat Fluxes and the Gulf Stream and Kuroshio–Oyashio Extension Variability  

Science Conference Proceedings (OSTI)

Spatial and temporal covariability between the atmospheric transient eddy heat fluxes (i.e., ??T? and ??q?) in the Northern Hemisphere winter (January–March) and the paths of the Gulf Stream (GS), Kuroshio Extension (KE), and Oyashio Extension ...

Young-Oh Kwon; Terrence M. Joyce

2013-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Variational Data Assimilation for Determining the Seasonal Net Surface Heat Flux Using a Tropical Pacific Ocean Model  

Science Conference Proceedings (OSTI)

The authors present a study for determining the seasonal net surface heat flux over the tropical Pacific Ocean using an adjoint technique. A simple tropical ocean model with thermodynamics is chosen and the seasonal sea surface temperature (SST) ...

Lisan Yu; James J. O'Brien

1995-10-01T23:59:59.000Z

282

Impact of Isopycnal Diffusion on Heat Fluxes and the Transient Response of a Two-Dimensional Ocean Model  

Science Conference Proceedings (OSTI)

A two-dimensional (latitude–depth) ocean–climate model is used to assess the impact of calculating diffusive heat and salinity fluxes along and across isopycnal surfaces rather than in a vertical–horizontal coordinate system. Differences between ...

L. D. Danny Harvey

1995-09-01T23:59:59.000Z

283

Fine Adjustment of Large Scale Air-Sea Energy Flux Parameterizations by Direct Estimates of Ocean Heat Transport  

Science Conference Proceedings (OSTI)

An inverse technique is used to adjust uncertain coefficients and parameters in the bulk formulae of climatological air-sea energy fluxes in order to obtain an agreement of indirect estimates of meridional heat transport with direct estimates in ...

Hans-Jörg Isemer; Jürgen Willebrand; Lutz Hasse

1989-10-01T23:59:59.000Z

284

Investigation of downward facing critical heat flux with water-based nanofluids for In-Vessel Retention applications.  

E-Print Network (OSTI)

??In-Vessel Retention ("IVR") is a severe accident management strategy that is power limiting to the Westinghouse AP1000 due to critical heat flux ("CHF") at the… (more)

DeWitt, Gregory L

2011-01-01T23:59:59.000Z

285

Using Similarity Theory to Parameterize Mesoscale Heat Fluxes Generated by Subgrid-Scale Landscape Discontinuities in GCMs  

Science Conference Proceedings (OSTI)

Similarity theory was used to develop a parameterization of mesoscale heat fluxes induced by landscape discontinuities for large-scale atmospheric models (e.g., general circulation models). For this purpose, Buckingham Pi theory, a systematic ...

Barry H. Lynn; Frank Abramopoulos; Roni Avissar

1995-04-01T23:59:59.000Z

286

Sensitivity of shortwave radiative flux density, forcing, and heating rates to the aerosol vertical profile  

SciTech Connect

The effect of the aerosol vertical distribution on the solar radiation profiles, for idealized and measured profiles of optical properties (extinction and single-scattering albedo (SSA)) during the May 2003 Atmospheric Radiation Measurement (ARM) Aerosol Intensive Observation Period (AIOP), has been investigated using the Rapid Radiative Transfer Model Shortwave (RRTM_SW) code. Calculated profiles of down-welling and up-welling solar fluxes during the AIOP have been compared with the data measured by up- and down-looking solar broadband radiometers aboard a profiling research aircraft. The measured profiles of aerosol extinction, SSA, and water vapor obtained from the same aircraft that carried the radiometers served as the inputs for the model calculations. It is noteworthy that for this study, the uplooking radiometers were mounted on a stabilized platform that kept the radiometers parallel with respect to the earth’s horizontal plane. The results indicate that the shape of the aerosol extinction profiles has very little impact on direct radiative forcings at the top of atmosphere and surface in a cloud-free sky. However, as long as the aerosol is not purely scattering, the shape of the extinction profiles is important for forcing profiles. Identical extinction profiles with different absorption profiles drastically influence the forcing and heating rate profiles. Using aircraft data from 19 AIOP profiles over the Southern Great Plains (SGP), we are able to achieve broadband down-welling solar flux closure within 0.8% (bias difference) or 1.8% (rms difference), well within the expected measurement uncertainty of 1 to 3%. The poorer agreement in up-welling flux (bias -3.7%, rms 10%) is attributed to the use of inaccurate surface albedo data. The sensitivity tests reveal the important role accurate, vertically resolved aerosol extinction data plays in tightening flux closure. This study also suggests that in the presence of a strongly absorbing substance, aircraft flux measurements from a stabilized platform have the potential to determine heating rate profiles. These measurement-based heating rate profiles provide useful data for heating rate closure studies and indirect estimates of single scattering albedo assumed in radiative transfer calculations.

Guan, Hong; Schmid, Beat; Bucholtz, Anthony; Bergstrom, Robert

2010-03-31T23:59:59.000Z

287

Stability of the Atlantic Overturning Circulation: Competition between Bering Strait Freshwater Flux and Agulhas Heat and Salt Sources  

Science Conference Proceedings (OSTI)

The role played by interocean fluxes of buoyancy in stabilizing the present-day overturning circulation of the Atlantic Ocean is examined. A 2D model of the Atlantic overturning circulation is used, in which the interocean fluxes of heat and salt ...

Wilbert Weijer; Wilhelmus P. M. De Ruijter; Henk A. Dijkstra

2001-08-01T23:59:59.000Z

288

Cooling by Heat Conduction Inside Magnetic Flux Loops and the Moderate Cluster Cooling Flow Model  

E-Print Network (OSTI)

I study non-radiative cooling of X-ray emitting gas via heat conduction along magnetic field lines inside magnetic flux loops in cooling flow clusters of galaxies. I find that such heat conduction can reduce the fraction of energy radiated in the X-ray band by a factor of 1.5-2. This non-radiative cooling joins two other proposed non-radiative cooling processes, which can be more efficient. These are mixing of cold and hot gas, and heat conduction initiated by magnetic fields reconnection between hot and cold gas. These processes when incorporated into the moderate cooling flow model lead to a general cooling flow model with the following ingredients. (1) Cooling flow does occur, but with a mass cooling rate about 10 times lower than in old versions of the cooling flow model. Namely, heating occurs such that the effective age of the cooling flow is much below the cluster age, but the heating can't prevent cooling altogether. (2) The cooling flow region is in a non-steady state evolution. (3) Non-radiative cooling of X-ray emitting gas can bring the model to a much better agreement with observations. (4) The general behavior of the cooling flow gas, and in particular the role played by magnetic fields, make the intracluster medium in cooling flow clusters similar in some aspects to the active solar corona.

Noam Soker

2003-11-02T23:59:59.000Z

289

Flux  

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

5000 5000 6000 7000 8000 Wavelength (Angstroms) Flux (in arbitrary units) SN 1990N SN 1989B SN 1993O SN 1981B SN 1994D SN 1997ap Iron Peak Blends Ca II Si II & Co II Fe II & III Day -7 Day -5 Day -4 Day -2 ± 2 Day 0 Day +2 * -50 0 50 100 150 Observed days from peak Observed I magnitude 27 26 25 24 23 Observed R magnitude 27 26 25 24 Observed I magnitude 27 26 25 24 23 R band Ground-based I band HST I band (b) (c) (a) Pre-SN observation 3.5 4.0 4.5 5.0 5.5 log(cz) 14 16 18 20 22 24 26 effective m B 0.02 0.05 0.1 0.2 0.5 1.0 redshift z Hamuy et al (A.J. 1996) Supernova Cosmology Project 6 8 % 9 0 % 0.5 1.0 1.5 2.0 2.5 3.0 ! M Age < 9.6 Gyr (H = 50 km s -1 Mpc -1 ) No Big Bang 0.0 0.5 1.0 1.5 2.0 2.5 3.0 -3 -2 -1 0 1 2 3 -3 -2 -1 0 1 2 3 ! " z ~ 0 . 4 z = 0 . 8 3 6 8 % 9 0 % 0.5 1.0 1.5 2.0 2.5 3.0 ! M Age < 9.6 Gyr (H=50 km/s/Mpc)

290

The Psychrometric Constant Is Not Constant: A Novel Approach to Enhance the Accuracy and Precision of Latent Energy Fluxes through Automated Water Vapor Calibrations  

Science Conference Proceedings (OSTI)

Numerous agencies, programs, and national networks are focused on improving understanding of water and energy fluxes across temporal and spatial scales and on enhancing confidence to synthesize data across multiple sites. Enhancing the accuracy ...

H. W. Loescher; C. V. Hanson; T. W. Ocheltree

2009-10-01T23:59:59.000Z

291

Creation of a Heat and Salt Flux Dataset Associated with Sea Ice Production and Melting in the Sea of Okhotsk  

Science Conference Proceedings (OSTI)

Sea ice formation, its transport, and its melting cause the redistribution of heat and salt, which plays an important role in the climate and biogeochemical systems. In the Sea of Okhotsk, a heat and salt flux dataset is created in which such sea ...

Sohey Nihashi; Kay I. Ohshima; Noriaki Kimura

2012-04-01T23:59:59.000Z

292

The Seasonal Cycle of Atmospheric Heating and Temperature  

Science Conference Proceedings (OSTI)

The seasonal cycle of the heating of the atmosphere is divided into a component due to direct solar absorption in the atmosphere and a component due to the flux of energy from the surface to the atmosphere via latent, sensible, and radiative heat ...

Aaron Donohoe; David S. Battisti

2013-07-01T23:59:59.000Z

293

Elementary Heating Events - Magnetic Interactions Between Two Flux Sources. III Energy Considerations  

E-Print Network (OSTI)

The magnetic field plays a crucial role in heating the solar corona, but the exact energy release mechanism(s) is(are) still unknown. Here, we investigate in detail, the process of magnetic energy release in a situation where two initially independent flux systems are forced into each other. Work done by the foot point motions goes in to building a current sheet in which magnetic reconnection takes place. The scaling relations of the energy input and output are determined as functions of the driving velocity and the strength of fluxes in the independent flux systems. In particular, it is found that the energy injected into the system is proportional to the distance travelled not the rate of travel. Similarly, the rate of Joule dissipation is related to the distance travelled. Hence, rapidly driven foot points lead to bright, intense, but short-lived events, whilst slowly driven foot points produce weaker, but longer-lived brightenings. Integrated over the lifetime of the events both would produce the same hea...

Galsgaard, K

2005-01-01T23:59:59.000Z

294

Transient thermal analysis of three fast-charging latent heat storage configurations for a space-based power system  

DOE Green Energy (OSTI)

A space-based thermal storage application must accept large quantities of heat in a short period of time at an elevated temperature. A model of a lithium hydride phase change energy storage system was used to estimate reasonable physical dimensions for this application which included the use of a liquid metal heat transfer fluid. A finite difference computer code was developed and used to evaluate three methods of enhancing heat transfer in the PCM energy storage system. None of these three methods, inserting thin fins, reticulated nickel, or liquid lithium, significantly improved the system performance. The use of a 95% void fraction reticulated nickel insert was found to increase the storage capacity (total energy stored) of the system slightly with only a small decrease in the system energy density (energy storage/system mass). The addition of 10% liquid lithium was found to cause minor increases in both storage density and storage capacity with the added benefit of reducing the hydrogen pressure of the lithium hydride. 9 refs., 7 figs., 2 tabs.

Stovall, T.K.; Arimilli, R.V.

1988-01-01T23:59:59.000Z

295

Parallel transport of long mean-free-path plasma along open magnetic field lines: Parallel heat flux  

SciTech Connect

In a long mean-free-path plasma where temperature anisotropy can be sustained, the parallel heat flux has two components with one associated with the parallel thermal energy and the other the perpendicular thermal energy. Due to the large deviation of the distribution function from local Maxwellian in an open field line plasma with low collisionality, the conventional perturbative calculation of the parallel heat flux closure in its local or non-local form is no longer applicable. Here, a non-perturbative calculation is presented for a collisionless plasma in a two-dimensional flux expander bounded by absorbing walls. Specifically, closures of previously unfamiliar form are obtained for ions and electrons, which relate two distinct components of the species parallel heat flux to the lower order fluid moments such as density, parallel flow, parallel and perpendicular temperatures, and the field quantities such as the magnetic field strength and the electrostatic potential. The plasma source and boundary condition at the absorbing wall enter explicitly in the closure calculation. Although the closure calculation does not take into account wave-particle interactions, the results based on passing orbits from steady-state collisionless drift-kinetic equation show remarkable agreement with fully kinetic-Maxwell simulations. As an example of the physical implications of the theory, the parallel heat flux closures are found to predict a surprising observation in the kinetic-Maxwell simulation of the 2D magnetic flux expander problem, where the parallel heat flux of the parallel thermal energy flows from low to high parallel temperature region.

Guo Zehua; Tang Xianzhu [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2012-06-15T23:59:59.000Z

296

Critical heat-flux experiments under low-flow conditions in a vertical annulus. [PWR; BWR; LMFBR  

Science Conference Proceedings (OSTI)

An experimental study was performed on critical heat flux (CHF) at low flow conditions for low pressure steam-water upward flow in an annulus. The test section was transparent, therefore, visual observations of dryout as well as various instrumentations were made. The data indicated that a premature CHF occurred due to flow regime transition from churn-turbulent to annular flow. It is shown that the critical heat flux observed in the experiment is essentially similar to a flooding-limited burnout and the critical heat flux can be well reproduced by a nondimensional correlation derived from the previously obtained criterion for flow regime transition. The observed CHF values are much smaller than the standard high quality CHF criteria at low flow, corresponding to the annular flow film dryout. This result is very significant, because the coolability of a heater surface at low flow rates can be drastically reduced by the occurrence of this mode of CHF.

Mishima, K.; Ishii, M.

1982-03-01T23:59:59.000Z

297

Investigating the use of nanofluids to improve high heat flux cooling systems  

E-Print Network (OSTI)

The thermal performance of high heat flux components in a fusion reactor could be enhanced significantly by the use of nanofluid coolants, suspensions of a liquid with low concentrations of solid nanoparticles. However, before they are considered viable for fusion, the long-term behaviour of nanofluids must be investigated. This paper reports an experiment which is being prepared to provide data on nanofluid stability, settling and erosion in a HyperVapotron device. Procedures are demonstrated for nanofluid synthesis and quality assessment, and the fluid sample analysis methods are described. The end results from this long-running experiment are expected to allow an initial assessment of the suitability of nanofluids as coolants in a fusion reactor.

Barrett, T R; Flinders, K; Sergis, A; Hardalupas, Y

2013-01-01T23:59:59.000Z

298

ROLE OF MAGNETIC FIELD STRENGTH AND NUMERICAL RESOLUTION IN SIMULATIONS OF THE HEAT-FLUX-DRIVEN BUOYANCY INSTABILITY  

SciTech Connect

The role played by magnetic fields in the intracluster medium (ICM) of galaxy clusters is complex. The weakly collisional nature of the ICM leads to thermal conduction that is channeled along field lines. This anisotropic heat conduction profoundly changes the instabilities of the ICM atmosphere, with convective stabilities being driven by temperature gradients of either sign. Here, we employ the Athena magnetohydrodynamic code to investigate the local non-linear behavior of the heat-flux-driven buoyancy instability (HBI) relevant in the cores of cooling-core clusters where the temperature increases with radius. We study a grid of two-dimensional simulations that span a large range of initial magnetic field strengths and numerical resolutions. For very weak initial fields, we recover the previously known result that the HBI wraps the field in the horizontal direction, thereby shutting off the heat flux. However, we find that simulations that begin with intermediate initial field strengths have a qualitatively different behavior, forming HBI-stable filaments that resist field-line wrapping and enable sustained vertical conductive heat flux at a level of 10%-25% of the Spitzer value. While astrophysical conclusions regarding the role of conduction in cooling cores require detailed global models, our local study proves that systems dominated by the HBI do not necessarily quench the conductive heat flux.

Avara, Mark J.; Reynolds, Christopher S. [Department of Astronomy, University of Maryland, College Park, MD 20740 (United States); Bogdanovic, Tamara, E-mail: mavara@astro.umd.edu, E-mail: chris@astro.umd.edu, E-mail: tamarab@gatech.edu [Center for Relativistic Astrophysics, School of Physics, Georgia Tech, Atlanta, GA 30332 (United States)

2013-08-20T23:59:59.000Z

299

On the hot-spot-controlled critical heat flux mechanism in pool boiling of saturated fluids  

SciTech Connect

In this paper, we further investigate the hypothesis that the critical heat flux (CHF) occurs when some point on the heated surface reaches a high enough temperature that liquid can no longer contact that point, resulting in a gradual but continuous increase in the overall surface temperature. This hypothesis unifies the occurrence of the CHF and the quenching of hot surfaces by relating both to the same concept, i.e., the ability of a liquid to contact a hot surface. We use a two-dimensional transient conduction model to study the boiling phenomenon in the second transition region of saturated pool nucleate boiling on a horizontal surface. The heater surface is assumed to consist of two regions: a dry patch region formed as a result of complete evaporation of the thinner liquid macrolayers and a two-phase macrolayer region formed by numerous vapor stems penetrating relatively thick liquid macrolayers. The constitutive relations used to determine the stem-macrolayer configuration in the two-phase macrolayer region of the boiling surface were reevaluated for Gaertner's clean water and water-nickel/salt solution. 29 refs.

Unal, C.; Sadasivan, P.; Nelson, R.A.

1992-01-01T23:59:59.000Z

300

On the hot-spot-controlled critical heat flux mechanism in pool boiling of saturated fluids  

SciTech Connect

In this paper, we further investigate the hypothesis that the critical heat flux (CHF) occurs when some point on the heated surface reaches a high enough temperature that liquid can no longer contact that point, resulting in a gradual but continuous increase in the overall surface temperature. This hypothesis unifies the occurrence of the CHF and the quenching of hot surfaces by relating both to the same concept, i.e., the ability of a liquid to contact a hot surface. We use a two-dimensional transient conduction model to study the boiling phenomenon in the second transition region of saturated pool nucleate boiling on a horizontal surface. The heater surface is assumed to consist of two regions: a dry patch region formed as a result of complete evaporation of the thinner liquid macrolayers and a two-phase macrolayer region formed by numerous vapor stems penetrating relatively thick liquid macrolayers. The constitutive relations used to determine the stem-macrolayer configuration in the two-phase macrolayer region of the boiling surface were reevaluated for Gaertner`s clean water and water-nickel/salt solution. 29 refs.

Unal, C.; Sadasivan, P.; Nelson, R.A.

1992-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Chaotic flow in a 2D natural convection loop with heat flux boundaries William F. Louisos a,b,  

E-Print Network (OSTI)

. Examples of natural convection cells occurring in engineering devices include solar water heaters, nu into the system while the upper half is cooled by an equal-but- opposite heat flux out of the system. Water between landmass and an adjacent body of water; mantle convection of the Earth's asthenosphere which

Danforth, Chris

302

An Assessment of the Surface Turbulent Heat Fluxes from the NCEP–NCAR Reanalysis over the Western Boundary Currents  

Science Conference Proceedings (OSTI)

With the completion of the NCEP–NCAR and ECMWF reanalyses there are now global representations of air–sea surface heat fluxes with sufficient spatial and temporal resolution to be useful in characterizing the air–sea interaction associated with ...

G. W. K. Moore; I. A. Renfrew

2002-08-01T23:59:59.000Z

303

Spatial Variability of Net Radiation and Soil Heat Flux Density on Two Logged Sites at Montmorency, Quebec  

Science Conference Proceedings (OSTI)

Net radiation data from 32 sample points and soil heat flux density values from six sample points on two logged sites at Montmorency in 1979 are presented. The two sites were of different ages; one had been clearcut in 1975 and the other in 1978. ...

J. H. McCaughey

1982-06-01T23:59:59.000Z

304

The Nature of the Poleward Heat Flux Due to Low-Frequency Current Fluctuations in Drake Passage  

Science Conference Proceedings (OSTI)

Values of poleward heat flux due to low-frequency current fluctuations in Drake Passage are presented for 19 long-term current meter records obtained during 1975, 1976 and 1977. Most of the measurements (10) are in the center of the passage near ...

Frank Sciremammano Jr.

1980-06-01T23:59:59.000Z

305

NACP Site-Model and Aggregated Flux Data Published  

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

Site-Model and Aggregated Flux Data Published Site-Model and Aggregated Flux Data Published The ORNL DAAC is pleased to announce the release of a data set from the North American Carbon Program (NACP): NACP Site: Terrestrial Biosphere Model and Aggregated Flux Data in Standard Format . Data set prepared by D.M. Ricciuto, K. Schaefer, P.E. Thornton, K. Davis, R.B. Cook, Shishi Liu, R. Anderson, M.A. Arain, I. Baker, J.M. Chen, M. Dietze, R. Grant, C. Izaurralde, A.K. Jain, A.W. King, C. Kucharik, Shuguang Liu, E. Lokupitiya, Y. Luo, C. Peng, B. Poulter, D. Price, W. Riley, A. Sahoo, H. Tian, C. Tonitto, and H. Verbeeck. This data set provides standardized output variables for gross primary productivity (GPP), net ecosystem exchange (NEE), leaf area index (LAI), ecosystem respiration (Re), latent heat flux (LE), and sensible heat flux (H) from 24

306

Proceedings of US/Japan workshop, Q219 on high heat flux components and plasma surface interactions for next fusion devices  

Science Conference Proceedings (OSTI)

This report contains the viewgraphs from the proceedings of US/Japan Workshop on High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices. Some of the general topics covered by this report are: PFC/PSI in tokamak and helical devices; development of high heat flux components; PSIS and plasma facing materials;tritium; and material damage.

Ulrickson, M.A.; Stevens, P.L.; Hino, T.; Hirohata, Y. [eds.] [eds.

1996-12-01T23:59:59.000Z

307

Design of Phosphor Thermometry System for Transient High Heat Flux Surface Thermometry  

SciTech Connect

Abstract: A transformative calibration methodology is presented for predicting transient surface temperatures in a thermally conducting medium from in-depth, time-varying temperature measurements. The surface temperature is resolved using two experimental runs and a newly devised first-kind Volterra integral equation. The first experimental run involves calibration with known surface temperature while the second run involves resolving the surface temperature of interest through the ill-posed integral equation. This paper presents the concept genesis and numerically demonstrates the concept for feasibility, robustness, stability and accuracy. From this demonstration, we propose to implement surface placed thermographic phosphors in the calibration stage of the inverse method for estimating the required surface temperature. As a preliminary study, we consider transient, constant property, onedimensional heat conduction in a semi-infinite medium. It is mathematically demonstrated that a Volterra integral equation of the first kind is developed for estimating the surface temperature using a calibrated system (host material and sensor). Sensor characterization, explicit sensor positioning and thermophysical properties are implicitly contained in the new calibration integral equation. The calibration integral equation displays only four terms; namely, the measured front surface temperature and corresponding measured in-depth temperature response associated with the calibration run; and, the unknown surface temperature and its measured in-depth temperature response associated with the second run. Preliminary numerical results indicate the merit of the concept. This paper suggests using thermographic phosphors for estimating the surface temperature in the calibration portion of the process owing to their rapid thermal response, good surface thermal contact characteristics and lack of capacitance for assuring minimal delay. Though the present paper describes the theoretical basis for resolving such problems, it is intended for near-term application using the UTK s high-heat flux laser facility which is presently under development

Allison, Stephen W [ORNL; Frankel, Jay I [ORNL; Beshears, David L [EMCO

2012-01-01T23:59:59.000Z

308

Time-Mean Flow as the Prevailing Contribution to the Poleward Heat Flux across the Southern Flank of the Antarctic Circumpolar Current: A Case Study in the Fawn Trough, Kerguelen Plateau  

Science Conference Proceedings (OSTI)

The major mechanisms of the oceanic poleward heat flux in the Southern Ocean are still in debate. The long-standing belief stipulates that the poleward heat flux across the Antarctic Circumpolar Current (ACC) is mainly due to mesoscale transient ...

H. Sekma; Y.-H. Park; F. Vivier

2013-03-01T23:59:59.000Z

309

Latent Matcher Fusion  

Science Conference Proceedings (OSTI)

Page 1. Latent Matcher Fusion -- Lessons Learned IAI ... 14 Page 15. The Fusion was in Two Steps • Step 1 – a reduced working candidate list was ...

2012-08-07T23:59:59.000Z

310

Experimental Investigation of Bendable Heat Pipes.  

E-Print Network (OSTI)

??Heat pipes are highly conductive heat transfer devices. They use the latent heat of the working fluid for efficient heat transfer over a very small… (more)

ODHEKAR, DHANANJAY

2005-01-01T23:59:59.000Z

311

Heat transfer and pressure drop data for high heat flux densities to water at high subcritical pressures  

E-Print Network (OSTI)

Local surface ooeffioients of heat t-ansfer, overall pressure drop data and mean friction factor are presented for heat flamms up to 3.52106 BtuAr ft2 for water flowing in a nickel tabe isder the following conditions: mass ...

Rohsenow, Warren M.

1951-01-01T23:59:59.000Z

312

Comparison of Heat Fluxes from Summertime Observations in the Suburbs of Four North American Cities  

Science Conference Proceedings (OSTI)

Previous measurements of urban energy balances have been restricted to a small number of cities. This paper presents directly measured energy balance fluxes for suburban areas in four cities within the United States: Tucson, Sacramento, Chicago, ...

C. S. B. Grimmond; T. R. Oke

1995-04-01T23:59:59.000Z

313

Mass, Heat, Salt and Nutrient Fluxes in the South Pacific Ocean  

Science Conference Proceedings (OSTI)

An inverse method has been applied to the Scorpio sections spanning the subtropical gyre of the South Pacific. In addition to constraints upon geostrophic fluxes of mass and salt, constraints were written for silica, oxygen and “PO”, and the ...

Carl Wunsch; Dunxin Hu; Barbara Grant

1983-05-01T23:59:59.000Z

314

Retrieval of Surface Heat and Moisture Fluxes from Slow-launched Radiosondes  

Science Conference Proceedings (OSTI)

Recently, there has been growing emphasis on improving surface flux inputs to mesoscale models and general circulation models. Since there is presently no operational network providing this information, we have conducted a feasibility experiment ...

Eric A. Smith; Harry J. Cooper; William L. Crosson; Donald D. Delorey

1991-12-01T23:59:59.000Z

315

Determining Turbulent Vertical Velocity, and Fluxes of Heat and Salt with an Autonomous Underwater Vehicle  

Science Conference Proceedings (OSTI)

The authors show that vertical turbulent fluxes in the upper ocean can be measured directly with an autonomous underwater vehicle (AUV). A horizontal profile of vertical water velocity is obtained by applying a Kalman smoother to AUV motion data. ...

Daniel R. Hayes; James H. Morison

2002-05-01T23:59:59.000Z

316

Using Transformation and Formation Maps to Study the Role of Air–Sea Heat Fluxes in North Atlantic Eighteen Degree Water Formation  

Science Conference Proceedings (OSTI)

The Walin water mass framework quantifies the rate at which water is transformed from one temperature class to another by air–sea heat fluxes (transformation). The divergence of the transformation rate yields the rate at which a given temperature ...

Guillaume Maze; Gael Forget; Martha Buckley; John Marshall; Ivana Cerovecki

2009-08-01T23:59:59.000Z

317

Sensible Heat Flux by Surface Layer Scintillometry and Eddy Covariance over a Mixed Grassland Community as Affected by Bowen Ratio and MOST Formulations for Unstable Conditions  

Science Conference Proceedings (OSTI)

Measurements of sensible heat flux for an extended period for unstable conditions using surface layer scintillometry (SLS) and eddy covariance (EC) and supplemented by Bowen ratio measurements for a mixed grassland community on the eastern ...

G. O. Odhiambo; M. J. Savage

2009-04-01T23:59:59.000Z

318

Field Results from a Second-Generation Ocean/Lake Surface Contact Heat Flux, Solar Irradiance, and Temperature Measurement Instrument—The Multisensor Float  

Science Conference Proceedings (OSTI)

This paper describes results from two field programs that support development of a wave-following surface contact multisensor float (MSF) designed to simultaneously measure net surface heat flux, net solar irradiance, and water temperature. The ...

J. P. Boyle

2007-05-01T23:59:59.000Z

319

A Comparison of ECMWF, NCEP–NCAR, and SOC Surface Heat Fluxes with Moored Buoy Measurements in the Subduction Region of the Northeast Atlantic  

Science Conference Proceedings (OSTI)

The accuracy of surface heat flux estimates from the NCEP–NCAR and ECMWF atmospheric model reanalyses is assessed by comparison with Woods Hole Oceanographic Institute research buoy measurements made during the Subduction Experiment in the ...

S. A. Josey

2001-04-01T23:59:59.000Z

320

Surface fluxes important to cloud development  

SciTech Connect

To address some of the issues in scaling and averaging of measurements, collaborative field campaigns were conducted in June 1991 and 1992 by the DOE laboratories funded under the ARM program. We selected a site in Boardman, OR, with two distinct regions where the sensible and latent heat fluxes would differ sharply and where each region was sufficiently extensive for full development of boundary layers and for utilizing aircraft-mounted instrument systems (Barnes et al. 1992, Doran et al. 1992). Measurements were clustered along a 16-km transect across adjoining irrigated farmland and semi-arid rangeland regions that allowed the collaborating teams to conduct a variety of studies relating to overall goals. The Los Alamos team efforts were focused on assessing the effects of different surface characteristics on fluxes of heat and water vapor.

Barnes, F.J.; Porch, W. [Los Alamos National Lab., NM (United States); Kunkel, K.E. [Illinois State Water Survey, Champaign, IL (United States)

1993-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Surface fluxes important to cloud development  

SciTech Connect

To address some of the issues in scaling and averaging of measurements, collaborative field campaigns were conducted in June 1991 and 1992 by the DOE laboratories funded under the ARM program. We selected a site in Boardman, OR, with two distinct regions where the sensible and latent heat fluxes would differ sharply and where each region was sufficiently extensive for full development of boundary layers and for utilizing aircraft-mounted instrument systems (Barnes et al. 1992, Doran et al. 1992). Measurements were clustered along a 16-km transect across adjoining irrigated farmland and semi-arid rangeland regions that allowed the collaborating teams to conduct a variety of studies relating to overall goals. The Los Alamos team efforts were focused on assessing the effects of different surface characteristics on fluxes of heat and water vapor.

Barnes, F.J.; Porch, W. (Los Alamos National Lab., NM (United States)); Kunkel, K.E. (Illinois State Water Survey, Champaign, IL (United States))

1993-01-01T23:59:59.000Z

322

Bayesian Nonparametric Latent Feature Models  

E-Print Network (OSTI)

3 Bayesian Nonparametric Latent Feature Model Inference5 Non-exchangeable Bayesian Nonparametric Inferencefor Non-exchangeable Bayesian Nonparametric Latent ture

Miller, Kurt Tadayuki

2011-01-01T23:59:59.000Z

323

Effect of TiO2 on the Conduction Heat Transfer of Mold Flux  

Science Conference Proceedings (OSTI)

Symposium, 2nd International Symposium on High-Temperature Metallurgical Processing. Presentation Title, Effect of TiO2 on the Conduction Heat Transfer of

324

Characterization of the Heat-Affected Zone in Flux-Cored Arc ...  

Science Conference Proceedings (OSTI)

Abstract Scope, To prepare for a study of the effect of heat-affect zone microstructure ... were optimized based on preliminary test trials on one inch thick pipes.

325

Double-diffusive convection for a non-Newtonian fluid flow past a permeable surface embedded in a porous medium with uniform heat and mass fluxes  

Science Conference Proceedings (OSTI)

The problem of steady, laminar, double-diffusive mixed convective flow of a non-Newtonian power-law fluid past a vertical semi-infinite permeable surface embedded in a porous medium with uniform heat and mass fluxes. A mixed convection parameter for ... Keywords: heat and mass transfer, mixed convection, non-Newtonian fluid, numerical solution, porous media, suction or injection

Ali J. Chamkha

2008-03-01T23:59:59.000Z

326

EXPERIMENTAL INVESTIGATION OF THE EFFECTS OF ULTRASONIC VIBRATION ON BURNOUT HEAT FLUX WITH BOILING WATER. Final Summary Report, October 3, 1960-July 31, 1961  

SciTech Connect

Experimental results were obtained on the effect of an ultrasonic field on the burnout heat flux for water flowing at atmospheric pressure, through an annular flow channel formed by a 1/4-in.-diameter electrically heated tube and a concentric glass tube of 3/4-in. ID. The active length of the central heating element was 5 1/2 in. The ultrasonic transducer, which was operated at 25,000 cps and a maximum electrical input of 300 watts, was located at the inlet end of the flow channel. The ultrasonic waves were propagated in the water in the direction of flow and thus parallel to the surface of the heating element. Burnout conditions covered channel inlet flows from 1.61 to 6.25 ft/sec and subcooling from 16 to 28 deg F. No effect of the ultrasonic field on the burnout heat flux or on the visible boiling phenomena at burnout conditions was detectable. During boiling at heat fluxes well below burnout, the effect of the ultrasonic field was a reduction in the diameter of the envelope of bubble activity surrounding the heating element. Visual inspectibn appeared to show that this reduction was associated with a smaller average bubble size and a greater frequency of bubble formation. However, all evidence of the presence of the ultrasonic field vanished as the flow velocity increased or as the heat flux increased to the burnout level. (auth)

Romie, F.E.; Aronson, C.A.

1961-07-31T23:59:59.000Z

327

Sea-Air Heat and Freshwater Fluxes in the Drake Passage and Western Scotia Sea  

Science Conference Proceedings (OSTI)

Hydrographic data from the vicinity of the Antarctic Polar Front in the Drake Passage and the western Scotia Sea are used to estimate the heat content and salinity differences for the upper ocean between summer and winter. Assuming that these ...

Alberto R. Piola; Daniel T. Georgi

1981-01-01T23:59:59.000Z

328

The Effects of Small-Scale Turbulence on Air–Sea Heat Flux  

Science Conference Proceedings (OSTI)

The air–sea exchange of heat is mainly controlled by the molecular diffusive layer adjacent to the surface. With an order of magnitude difference between the kinematic viscosity and thermal diffusivity of water, the thermal sublayer is embedded ...

Fabrice Veron; W. Kendall Melville; Luc Lenain

2011-01-01T23:59:59.000Z

329

Stationary temperature profiles and heat flux distribution in a plastic-encapsulated circuit package  

Science Conference Proceedings (OSTI)

Thermal characteristics that are important to structural integrity are analyzed herein for a TTL, plastic-encapsulated package. By assuming that total module heat during operation is engendered at idealized junctions between lead wires and the chip surface, ...

J. A. Paivanas

1972-05-01T23:59:59.000Z

330

A highly portable, rapidly deployable system for eddy covariance measurements of CO2 fluxes  

DOE Green Energy (OSTI)

To facilitate the study of flux heterogeneity within a region, the authors have designed, built, and field-tested a highly portable, rapidly deployable, eddy covariance CO{sub 2} flux measurement system. The system is built from off-the-shelf parts and was assembled at a minimal cost. The unique combination of features of this system allow for a very rapid deployment with a minimal number of field personnel. The system is capable of making high precision, unattended measurements of turbulent CO{sub 2} fluxes, latent heat (LE) fluxes, sensible heat fluxes (H), and momentum transfer fluxes. In addition, many of the meteorological and ecosystem variables necessary for quality control of the fluxes and for running ecosystem models are measured. A side-by-side field comparison of the system at a pair of established AmeriFlux sites has verified that, for single measurements, the system is capable of CO{sub 2} flux accuracy of about {+-} 1.2 {micro}mole/m{sup 2}/sec, LE flux accuracy of about {+-} 15 Watts/m{sup 2}, H flux accuracy of about {+-} 7 Watts/m{sup 2}, and momentum transfer flux accuracy of about {+-} 11 gm-m/sec/sec. System deployment time is between 2 and 4 hours by a single person. The system was measured to draw between 30 and 35 Watts of power and may be run from available line power, storage batteries, or solar panels.

Billesbach, David P.; Fischer, Marc L.; Torn, Margaret S.; Berry, Joe A.

2001-09-19T23:59:59.000Z

331

Areally averaged estimates of surface heat flux from ARM field studies  

SciTech Connect

The determination of areally averaged surface fluxes is a problem of fundamental interest to the Atmospheric Radiation Measurement (ARM) program. The Cloud And Radiation Testbed (CART) sites central to the ARM program will provide high-quality data for input to and verification of General Circulation Models (GCMs). The extension of several point measurements of surface fluxes within the heterogeneous CART sites to an accurate representation of the areally averaged surface fluxes is not straightforward. Two field studies designed to investigate these problems, implemented by ARM science team members, took place near Boardman, Oregon, during June of 1991 and 1992. The site was chosen to provide strong contrasts in surface moisture while minimizing the differences in topography. The region consists of a substantial dry steppe (desert) upwind of an extensive area of heavily irrigated farm land, 15 km in width and divided into 800-m-diameter circular fields in a close packed array, in which wheat, alfalfa, corn, or potatoes were grown. This region provides marked contrasts, not only on the scale of farm-desert (10--20 km) but also within the farm (0.1--1 km), because different crops transpire at different rates, and the pivoting irrigation arms provide an ever-changing pattern of heavy surface moisture throughout the farm area. This paper primarily discusses results from the 1992 field study.

Coulter, R.L.; Martin, T.J.; Cook, D.R.

1993-08-01T23:59:59.000Z

332

Comparing Simulated and Measured Sensible and Latent Heat Fluxes over Snow under a Pine Canopy to Improve an Energy Balance Snowmelt Model  

Science Conference Proceedings (OSTI)

During the second year of the NASA Cold Land Processes Experiment (CLPX), an eddy covariance (EC) system was deployed at the Local Scale Observation Site (LSOS) from mid-February to June 2003. The EC system was located beneath a uniform pine ...

D. Marks; A. Winstral; G. Flerchinger; M. Reba; J. Pomeroy; T. Link; K. Elder

2008-12-01T23:59:59.000Z

333

An experimental and numerical study of boundary layer structure over areas of inhomogeneous sensible heat fluxes  

SciTech Connect

In June of 1992 a boundary-layer experiment was carried out near Boardman, Oregon. The campaigns were part of a program of studies under the auspices of the US Department of Energy`s Atmospheric Radiation Measurement (ARM) program, whose goal is to improve the treatment of radiative transfer, particularly as affected by clouds, in general circulation models (GCMs) used for climate studies. One aspect of this program is concerned with the determination of appropriate lower boundary conditions for such models and the representation of subgrid-scale variability in regions where the surface conditions are not uniform. To study this problem, boundary-layer and surface properties were measured over a region of two sharply contrasting land types: a large, dry, sagebrush steppe area and irrigated farmland that formed the east, northeast, and western borders of the steppe. A combination of surface flux instrumentation, airsondes, sodars, and near-surface wind and temperature sensors was used. Measurements were carried out over the eastern portion of this region, which featured a well-defined boundary between the dry and irrigated areas. In this paper, the authors present some results from those observations and from a set of numerical simulations that address the effects of inhomogeneous surface fluxes on boundary-layer structure.

Zhong, S.; Doran, J.C.

1994-03-01T23:59:59.000Z

334

Air–Sea Heat Exchange along the Northern Sea Surface Temperature Front in the Eastern Tropical Pacific  

Science Conference Proceedings (OSTI)

The atmospheric response to the oceanic forcing in the eastern Pacific along the northern equatorial sea surface temperature (SST) front is investigated in terms of sensible and latent heat flux during the 6-month period from 28 July 1999 to 27 ...

Nicolai Thum; Steven K. Esbensen; Dudley B. Chelton; Michael J. McPhaden

2002-12-01T23:59:59.000Z

335

Hot-electron production and suprathermal heat flux scaling with laser intensity from the two-plasmon-decay instability  

SciTech Connect

The fully kinetic reduced-description particle-in-cell (RPIC) method has been applied to simulations of two-plasmon-decay (TPD) instability, driven by crossed laser beams, in an inhomogeneous plasma for parameters consistent with recent direct-drive experiments related to laser-driven inertial fusion. The nonlinear saturated state is characterized by very spiky electric fields, with Langmuir cavitation occurring preferentially inside density channels produced by the ponderomotive beating of the crossed laser beams and the primary TPD Langmuir waves (LWs). The heated electron distribution function is, in all cases, bi-Maxwellian, with instantaneous hot-electron temperatures in the range 60-100 keV. The net hot-electron energy flux out of the system is a small fraction ({approx}1% to 2%) of the input laser intensity in these simulations. Scalings of the hot-electron temperature and suprathermal heat flux as functions of the laser intensity are obtained numerically from RPIC simulations. These simulations lead to the preliminary conclusion that Langmuir cavitation and collapse provide dissipation by producing suprathermal electrons, which stabilize the system in saturation and drive the LW spectrum to the small dissipation scales at the Landau cutoff. The Langmuir turbulence originates at an electron density 0.241 Multiplication-Sign the laser's critical density, where the crossed laser beams excite a 'triad' mode-a common forward LW plus a pair of backward LWs. Remnants of this 'triad' evolve in k-space and dominate the time-averaged energy spectrum. At times exceeding 10 ps, the excited Langmuir turbulence spreads toward lower densities. Comparisons of RPIC simulations with the extended Zakharov model are presented in appropriate regimes, and the necessary requirements for the validity of a quasi-linear Zakharov model (where the spatially averaged electron-velocity distribution is evolved) are verified by RPIC simulation results.

Vu, H. X. [University of California, San Diego, La Jolla, California 92093 (United States); DuBois, D. F. [Lodestar Research Corporation, Boulder, Colorado 80301 (United States); Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Myatt, J. F. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Russell, D. A. [Lodestar Research Corporation, Boulder, Colorado 80301 (United States)

2012-10-15T23:59:59.000Z

336

Floating Refrigerant Loop Based on R-134a Refrigerant Cooling of High-Heat Flux Electronics  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) Power Electronics and Electric Machinery Research Center (PEEMRC) have been developing technologies to address the thermal issues associated with hybrid vehicles. Removal of the heat generated from electrical losses in traction motors and their associated power electronics is essential for the reliable operation of motors and power electronics. As part of a larger thermal control project, which includes shrinking inverter size and direct cooling of electronics, ORNL has developed U.S. Patent No. 6,772,603 B2, ''Methods and Apparatus for Thermal Management of Vehicle Systems and Components'' [1], and patent pending, ''Floating Loop System for Cooling Integrated Motors and Inverters Using Hot Liquid Refrigerant'' [2]. The floating-loop system provides a large coefficient of performance (COP) for hybrid-drive component cooling. This loop (based on R-134a) is integrated with a vehicle's existing air-conditioning (AC) condenser, which dissipates waste heat to the ambient air. Because the temperature requirements for cooling of power electronics and electric machines are not as low as that required for passenger compartment air, this adjoining loop can operate on the high-pressure side of the existing AC system. This arrangement also allows the floating loop to run without the need for the compressor and only needs a small pump to move the liquid refrigerant. For the design to be viable, the loop must not adversely affect the existing system. The loop should also provide a high COP, a flat-temperature profile, and low-pressure drop. To date, the floating-loop test prototype has successfully removed 2 kW of heat load in a 9 kW automobile passenger AC system with and without the automotive AC system running. The COP for the tested floating-loop system ranges from 40-45, as compared to a typical AC system COP of about 2-4. The estimated required waste-heat load for future hybrid applications is 5.5 kW and the existing system could be easily scaleable for this larger load.

Lowe, K.T.

2005-10-07T23:59:59.000Z

337

Floating Refrigerant Loop Based on R-134a Refrigerant Cooling of High-Heat Flux Electronics  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) Power Electronics and Electric Machinery Research Center (PEEMRC) have been developing technologies to address the thermal issues associated with hybrid vehicles. Removal of the heat generated from electrical losses in traction motors and their associated power electronics is essential for the reliable operation of motors and power electronics. As part of a larger thermal control project, which includes shrinking inverter size and direct cooling of electronics, ORNL has developed U.S. Patent No. 6,772,603 B2, ''Methods and Apparatus for Thermal Management of Vehicle Systems and Components'' [1], and patent pending, ''Floating Loop System for Cooling Integrated Motors and Inverters Using Hot Liquid Refrigerant'' [2]. The floating-loop system provides a large coefficient of performance (COP) for hybrid-drive component cooling. This loop (based on R-134a) is integrated with a vehicle's existing air-conditioning (AC) condenser, which dissipates waste heat to the ambient air. Because the temperature requirements for cooling of power electronics and electric machines are not as low as that required for passenger compartment air, this adjoining loop can operate on the high-pressure side of the existing AC system. This arrangement also allows the floating loop to run without the need for the compressor and only needs a small pump to move the liquid refrigerant. For the design to be viable, the loop must not adversely affect the existing system. The loop should also provide a high COP, a flat-temperature profile, and low-pressure drop. To date, the floating-loop test prototype has successfully removed 2 kW of heat load in a 9 kW automobile passenger AC system with and without the automotive AC system running. The COP for the tested floating-loop system ranges from 40-45, as compared to a typical AC system COP of about 2-4. The estimated required waste-heat load for future hybrid applications is 5.5 kW and the existing system could be easily scaleable for this larger load.

Lowe, K.T.

2005-10-07T23:59:59.000Z

338

968 JOURNAL OF PHYSICAL OCEANOGRAPHY VOLUME 34 A New Method for Estimation of the Sensible Heat Flux under Unstable Conditions Using Satellite Vector Winds  

E-Print Network (OSTI)

It has been difficult to estimate the sensible heat flux at the air–sea interface using satellite data because of the difficulty in remotely observing the sea level air temperature. In this study, a new method is developed for estimating the sensible heat flux using satellite observations under unstable conditions. The basic idea of the method is that the air–sea temperature difference is related to the atmospheric convergence. Employed data include the wind convergence, sea level humidity, and sea surface temperature. These parameters can be derived from the satellite wind vectors, Special Sensor Microwave Imager (SSM/I) precipitable water, and Advanced Very High Resolution Radiometer (AVHRR) observations, respectively. The authors selected a region east of Japan as the test area where the atmospheric convergence appears all year. Comparison between the heat fluxes derived from the satellite data and from the National Centers for Environmental Prediction (NCEP) data suggests that the rms difference between the two kinds of sensible heat fluxes has low values in the sea area east of Japan with a minimum of 10.0 W m ?2. The time series of the two kinds of sensible heat fluxes at 10 locations in the area are in agreement, with rms difference ranging between 10.0 and 14.1 W m ?2 and correlation coefficient being higher than 0.7. In addition, the National Aeronautics and Space Administration (NASA) Goddard Satellite-Based Surface Turbulent Flux (GSSTF) was used for a further comparison. The low-rms region with high correlation coefficient (?0.7) was also found in the region east of Japan with a minimum of 12.2 W m ?2. Considering the nonlinearity in calculation of the sensible monthly means, the authors believe that the comparison with GSSTF is consistent with that with NCEP data. 1.

Jiayi Pan; Xiao-hai Yan; Young-heon Jo; Quanan Zheng; W. Timothy Liu

2003-01-01T23:59:59.000Z

339

Numerical investigation of edge plasma phenomena in an enhanced D-alpha discharge at Alcator C-Mod: Parallel heat flux and quasi-coherent edge oscillations  

SciTech Connect

Reduced-model scrape-off layer turbulence (SOLT) simulations of an enhanced D-alpha (EDA) H-mode shot observed in the Alcator C-Mod tokamak were conducted to compare with observed variations in the scrape-off-layer (SOL) width of the parallel heat flux profile. In particular, the role of the competition between sheath- and conduction-limited parallel heat fluxes in determining that width was studied for the turbulent SOL plasma that emerged from the simulations. The SOL width decreases with increasing input power and with increasing separatrix temperature in both the experiment and the simulation, consistent with the strong temperature dependence of the parallel heat flux in balance with the perpendicular transport by turbulence and blobs. The particularly strong temperature dependence observed in the case analyzed is attributed to the fact that these simulations produce SOL plasmas which are in the conduction-limited regime for the parallel heat flux. A persistent quasi-coherent (QC) mode dominates the SOLT simulations and bears considerable resemblance to the QC mode observed in C-Mod EDA operation. The SOLT QC mode consists of nonlinearly saturated wave-fronts located just inside the separatrix that are convected poloidally by the mean flow, continuously transporting particles and energy and intermittently emitting blobs into the SOL.

Russell, D. A.; D'Ippolito, D. A.; Myra, J. R. [Lodestar Research Corporation, 2400 Central Ave., P-5, Boulder, Colorado 80301 (United States); LaBombard, B.; Terry, J. L. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 167 Albany Street, Cambridge, Massachusetts 02138 (United States); Zweben, S. J. [Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08540 (United States)

2012-08-15T23:59:59.000Z

340

Latent effects decision analysis  

DOE Patents (OSTI)

Latent effects on a system are broken down into components ranging from those far removed in time from the system under study (latent) to those which closely effect changes in the system. Each component is provided with weighted inputs either by a user or from outputs of other components. A non-linear mathematical process known as `soft aggregation` is performed on the inputs to each component to provide information relating to the component. This information is combined in decreasing order of latency to the system to provide a quantifiable measure of an attribute of a system (e.g., safety) or to test hypotheses (e.g., for forensic deduction or decisions about various system design options).

Cooper, J. Arlin (Albuquerque, NM); Werner, Paul W. (Albuquerque, NM)

2004-08-24T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Photovoltaic roof heat flux  

E-Print Network (OSTI)

and a major factor of energy usage (-37%) is the amount ofdesign approaches to reduce energy usage i n order to coollongest, a n d hence the energy usage was the largest d u r

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

342

Photovoltaic roof heat flux  

E-Print Network (OSTI)

showed that a solar panel over a rooftop w i l l lead to aalbedo (or solar reflectance) by painting the rooftops whitesolar panel offset height became a key component for rooftop

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

343

Photovoltaic roof heat flux  

E-Print Network (OSTI)

represent the total H V A C energy usage for that day. Otherrepresent the total H V A C energy usage for that day. Other

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

344

Photovoltaic roof heat flux  

E-Print Network (OSTI)

many solar installations have basic weather stations. Withthe solar panels. Figure 6: Setup #1 on RIMAC roof. Weather

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

345

Forest understory soil temperatures and heat flux calculated using a Fourier model and scaled using a digital camera  

E-Print Network (OSTI)

uneven but periodic solar heating of the soil surface due tothe uneven but periodic solar heating of the soil due to a

Graham, Eric; Lam, Yeung; Yuen, Eric

2010-01-01T23:59:59.000Z

346

Pressure drop, heat transfer, critical heat flux, and flow stability of two-phase flow boiling of water and ethylene glycol/water mixtures - final report for project "Efficent cooling in engines with nucleate boiling."  

SciTech Connect

Because of its order-of-magnitude higher heat transfer rates, there is interest in using controllable two-phase nucleate boiling instead of conventional single-phase forced convection in vehicular cooling systems to remove ever increasing heat loads and to eliminate potential hot spots in engines. However, the fundamental understanding of flow boiling mechanisms of a 50/50 ethylene glycol/water mixture under engineering application conditions is still limited. In addition, it is impractical to precisely maintain the volume concentration ratio of the ethylene glycol/water mixture coolant at 50/50. Therefore, any investigation into engine coolant characteristics should include a range of volume concentration ratios around the nominal 50/50 mark. In this study, the forced convective boiling heat transfer of distilled water and ethylene glycol/water mixtures with volume concentration ratios of 40/60, 50/50, and 60/40 in a 2.98-mm-inner-diameter circular tube has been investigated in both the horizontal flow and the vertical flow. The two-phase pressure drop, the forced convective boiling heat transfer coefficient, and the critical heat flux of the test fluids were determined experimentally over a range of the mass flux, the vapor mass quality, and the inlet subcooling through a new boiling data reduction procedure that allowed the analytical calculation of the fluid boiling temperatures along the experimental test section by applying the ideal mixture assumption and the equilibrium assumption along with Raoult's law. Based on the experimental data, predictive methods for the two-phase pressure drop, the forced convective boiling heat transfer coefficient, and the critical heat flux under engine application conditions were developed. The results summarized in this final project report provide the necessary information for designing and implementing nucleate-boiling vehicular cooling systems.

Yu, W.; France, D. M.; Routbort, J. L. (Energy Systems)

2011-01-19T23:59:59.000Z

347

Heat storage materials. Final report  

DOE Green Energy (OSTI)

The properties of various alloys, eutectics, and salts in respect to their usefulness for latent and sensible heat storage are surveyed and reported. (TFD)

Birchenall, C.E.

1977-12-01T23:59:59.000Z

348

Gravity Wave 1-leat Fluxes: A Lagrangian Approach  

Science Conference Proceedings (OSTI)

The effect of a vertically propagating, internal gravity wave on the vertical flux of potential temperature (heat) is considered by averaging the local heat flux vector over a potential temperature surface. This approach gives the wave heat flux ...

Lawrence Coy; David C. Fritts

1988-06-01T23:59:59.000Z

349

Energy Balance Models Incorporating Transport of Thermal and Latent Energy  

Science Conference Proceedings (OSTI)

Standard latitudinally resolved energy balance models describe conservation of energy on a sphere subject to solar heating, cooling by infrared radiation and diffusive redistribution of energy according to a Fourier type heat flow with flux ...

Brian P. Flannery

1984-02-01T23:59:59.000Z

350

Content Modeling Using Latent Permutations  

E-Print Network (OSTI)

We present a novel Bayesian topic model for learning discourse-level document structure. Our model leverages insights from discourse theory to constrain latent topic assignments in a way that reflects the underlying ...

Chen, Harr

351

Observations of the Effect of Rain Temperature on the Surface Heat Flux in the Intertropical Convergence Zone  

Science Conference Proceedings (OSTI)

The thermohaline response of the ocean to a short (10 h) but intense (95 mm) nighttime rainfall event was observed during a transit through the ITCZ. Two CTD profiles and shipboard measurements of air–sea fluxes were consistent with the ...

P. Flament; M. Sawyer

1995-03-01T23:59:59.000Z

352

Surface Energy Fluxes of the South Atlantic Ocean  

Science Conference Proceedings (OSTI)

Fluxes of sensible, latent and radiational energy and momentum across the surface of the South Atlantic Ocean have been calculated by substituting ship meteorological observations into bulk aerodynamic and empirical radiation equations. Upper-air ...

Andrew F. Bunker

1988-04-01T23:59:59.000Z

353

Horizontal Heat Fluxes over Complex Terrain Computed Using a Simple Mixed-Layer Model and a Numerical Model  

Science Conference Proceedings (OSTI)

The thermally induced local circulation over a periodic valley is simulated by a two-dimensional numerical model that does not include condensational processes. During the daytime of a clear, calm day, heat is transported from the mountainous ...

Fujio Kimura; Tuneo Kuwagata

1995-02-01T23:59:59.000Z

354

Temperature and heat flux datasets of a complex object in a fire plume for the validation of fire and thermal response codes.  

SciTech Connect

It is necessary to improve understanding and develop temporally- and spatially-resolved integral scale validation data of the heat flux incident to a complex object in addition to measuring the thermal response of said object located within the fire plume for the validation of the SIERRA/FUEGO/SYRINX fire and SIERRA/CALORE codes. To meet this objective, a complex calorimeter with sufficient instrumentation to allow validation of the coupling between FUEGO/SYRINX/CALORE has been designed, fabricated, and tested in the Fire Laboratory for Accreditation of Models and Experiments (FLAME) facility. Validation experiments are specifically designed for direct comparison with the computational predictions. Making meaningful comparison between the computational and experimental results requires careful characterization and control of the experimental features or parameters used as inputs into the computational model. Validation experiments must be designed to capture the essential physical phenomena, including all relevant initial and boundary conditions. This report presents the data validation steps and processes, the results of the penlight radiant heat experiments (for the purpose of validating the CALORE heat transfer modeling of the complex calorimeter), and the results of the fire tests in FLAME.

Jernigan, Dann A.; Blanchat, Thomas K.

2010-09-01T23:59:59.000Z

355

metal-mold interface heat flux during gravity die-casting of al-b4c ...  

Science Conference Proceedings (OSTI)

The interfacial air gap introduces an additional resistance along the heat flow ... Determination and optimization best condition for Bioleaching of sulfide low ... Fabrication of functionally graded materials by directional solidification process under a ... of oxide dispersion strengthened alloys sintered by spark plasma sintering.

356

Thermal-hydraulic simulation of natural convection decay heat removal in the High Flux Isotope Reactor using RELAP5 and TEMPEST: Part 1, Models and simulation results  

Science Conference Proceedings (OSTI)

A study was conducted to examine decay heat removal requirements in the High Flux Isotope Reactor (HFIR) following shutdown from 85 MW. The objective of the study was to determine when forced flow through the core could be terminated without causing the fuel to melt. This question is particularly relevant when a station blackout caused by an external event is considered. Analysis of natural circulation in the core, vessel upper plenum, and reactor pool indicates that 12 h of forced flow will permit a safe shutdown with some margin. However, uncertainties in the analysis preclude conclusive proof that 12 h is sufficient. As a result of the study, two seismically qualified diesel generators were installed in HFIR. 9 refs., 4 figs.

Morris, D.G.; Wendel, M.W.; Chen, N.C.J.; Ruggles, A.E.; Cook, D.H.

1989-01-01T23:59:59.000Z

357

Measurement of gas species, temperatures, coal burnout, and wall heat fluxes in a 200 MWe lignite-fired boiler with different overfire air damper openings  

SciTech Connect

Measurements were performed on a 200 MWe, wall-fired, lignite utility boiler. For different overfire air (OFA) damper openings, the gas temperature, gas species concentration, coal burnout, release rates of components (C, H, and N), furnace temperature, and heat flux and boiler efficiency were measured. Cold air experiments for a single burner were conducted in the laboratory. The double-swirl flow pulverized-coal burner has two ring recirculation zones starting in the secondary air region in the burner. As the secondary air flow increases, the axial velocity of air flow increases, the maxima of radial velocity, tangential velocity and turbulence intensity all increase, and the swirl intensity of air flow and the size of recirculation zones increase slightly. In the central region of the burner, as the OFA damper opening widens, the gas temperature and CO concentration increase, while the O{sub 2} concentration, NOx concentration, coal burnout, and release rates of components (C, H, and N) decrease, and coal particles ignite earlier. In the secondary air region of the burner, the O{sub 2} concentration, NOx concentration, coal burnout, and release rates of components (C, H, and N) decrease, and the gas temperature and CO concentration vary slightly. In the sidewall region, the gas temperature, O{sub 2} concentration, and NOx concentration decrease, while the CO concentration increases and the gas temperature varies slightly. The furnace temperature and heat flux in the main burning region decrease appreciably, but increase slightly in the burnout region. The NOx emission decreases from 1203.6 mg/m{sup 3} (6% O{sub 2}) for a damper opening of 0% to 511.7 mg/m{sup 3} (6% O{sub 2}) for a damper opening of 80% and the boiler efficiency decreases from 92.59 to 91.9%. 15 refs., 17 figs., 3 tabs.

Jianping Jing; Zhengqi Li; Guangkui Liu; Zhichao Chen; Chunlong Liu [Harbin Institute of Technology, Harbin (China). School of Energy Science and Engineering

2009-07-15T23:59:59.000Z

358

Heat transfer in porous media with fluid phase changes  

DOE Green Energy (OSTI)

A one-dimensional experimental apparatus was built to study the heat pipe phenomenon. Basically, it consists of a 25 cm long, 2.5 cm I.D. Lexane tube packed with Ottawa sand. The two ends of the tube were subjected to different tempratures, i.e., one above the boiling temperature and the other below. The tube was well insulated so that a uniform one-dimensional heat flux could pass through the sand pack. Presence of the heat pipe phenomenon was confirmed by the temperature and saturation profiles of the sand pack at the final steady state condition. A one-dimensional steady state theory to describe the experiment has been developed which shows the functional dependence of the heat pipe phenomenon on liquid saturation gradient, capillary pressure, permeability, fluid viscosity, latent heat, heat flux and gravity. Influence of the heat pipe phenomenon on wellbore heat losses was studied by use of a two-phase two-dimensional cylindrical coordinate computer model.

Su, H.J.

1981-06-01T23:59:59.000Z

359

Sensitivity of Surface Flux Simulations to Hydrologic Parameters Based on an Uncertainty Quantification Framework Applied to the Community Land Model  

SciTech Connect

Uncertainties in hydrologic parameters could have significant impacts on the simulated water and energy fluxes and land surface states, which will in turn affect atmospheric processes and the carbon cycle. Quantifying such uncertainties is an important step toward better understanding and quantification of uncertainty of integrated earth system models. In this paper, we introduce an uncertainty quantification (UQ) framework to analyze sensitivity of simulated surface fluxes to selected hydrologic parameters in the Community Land Model (CLM4) through forward modeling. Thirteen flux tower footprints spanning a wide range of climate and site conditions were selected to perform sensitivity analyses by perturbing the parameters identified. In the UQ framework, prior information about the parameters was used to quantify the input uncertainty using the Minimum-Relative-Entropy approach. The quasi-Monte Carlo approach was applied to generate samples of parameters on the basis of the prior pdfs. Simulations corresponding to sampled parameter sets were used to generate response curves and response surfaces and statistical tests were used to rank the significance of the parameters for output responses including latent (LH) and sensible heat (SH) fluxes. Overall, the CLM4 simulated LH and SH show the largest sensitivity to subsurface runoff generation parameters. However, study sites with deep root vegetation are also affected by surface runoff parameters, while sites with shallow root zones are also sensitive to the vadose zone soil water parameters. Generally, sites with finer soil texture and shallower rooting systems tend to have larger sensitivity of outputs to the parameters. Our results suggest the necessity of and possible ways for parameter inversion/calibration using available measurements of latent/sensible heat fluxes to obtain the optimal parameter set for CLM4. This study also provided guidance on reduction of parameter set dimensionality and parameter calibration framework design for CLM4 and other land surface models under different hydrologic and climatic regimes.

Hou, Zhangshuan; Huang, Maoyi; Leung, Lai-Yung R.; Lin, Guang; Ricciuto, Daniel M.

2012-08-10T23:59:59.000Z

360

Variability of surface fluxes over a heterogeneous semi-arid grassland  

SciTech Connect

Efforts are increasing throughout the research community to improve the predictive capabilities of general circulation models (GCMs). The US Department of Energy's Atmospheric Radiation Measurement (ARM) program has stated its goals as improving the representation and parameterization of cloud radiative forcing and feedbacks in GCMs by a combined modeling and experimental approach. Along with ambient atmospheric conditions, including advection of water vapor and cloud nuclei from other regions, cloud dynamics depend on surface fluxes of heat and water vapor. The lower boundary of the GCM modeling domain, the earth's surface, exerts a strong influence on regional dynamics of heat and water vapor, and the heterogeneity in the surface features can be responsible for generating regional mesoscale circulation patterns. Changes in the surface vegetation due to anthropogenic activity can cause substantial changes in the ratio of sensible to latent heat flux and result in climate changes that may be irreversible. A broad variety of models for representing energy fluxes are in use, from individual leaf and canopy models to mesoscale atmospheric models and GCMs. Scaling-up a model is likely to result in significant errors, since biophysical responses often have nonlinear dependence on the abiotic environment. Thus, accurate and defensible methods for selecting measurement scales and modeling strategies are needed in the effort to improve GCMs. 7 refs., 4 figs., 1 tab.

Barnes, F.J.; Porch, W.; Cooper, D. (Los Alamos National Lab., NM (United States)); Kunkel, K.E. (Illinois Univ., Urbana, IL (United States)); Hipps, L.; Swiatek, E. (Utah State Univ., Logan, UT (United States))

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Validation and Sensitivity Analysis of a New Atmosphere–Soil–Vegetation Model. Part II: Impacts on In-Canopy Latent Heat Flux over a Winter Wheat Field Determined by Detailed Calculation of Canopy Radiation Transmission and Stomatal Resistance  

Science Conference Proceedings (OSTI)

This paper describes the validation and sensitivity analysis of an atmosphere–soil–vegetation model. The model consists of one-dimensional multilayer submodels for the atmosphere, soil, and vegetation and a radiation scheme for the transmission ...

Haruyasu Nagai

2003-03-01T23:59:59.000Z

362

Investigation of Heat Transfer Conditions in a Reverberatory Melting ...  

Science Conference Proceedings (OSTI)

The model comprises different physical phenomenon as gas f low, chemical reactions, i.e. combustion, conduction, radiation and latent heat release in the metal.

363

Heat-Flux Sensor Calibration  

Science Conference Proceedings (OSTI)

... 2. TT Gentile, JM Houston, JE Hardis, CL Cromer, and AC ... points) e. Test fee f. Address to ship test item g. Return shipping instructions (prepay ...

2012-11-02T23:59:59.000Z

364

Heat and mass transfer in unsaturated porous media. Final report  

DOE Green Energy (OSTI)

A preliminary study of heat and water transport in unsaturated porous media is reported. The project provides background information regarding the feasibility of seasonal thermal energy storage in unconfined aquifers. A parametric analysis of the factors of importance, and an annotated bibliography of research findings pertinent to unconfined aquifer thermal energy storage (ATES) are presented. This analysis shows that heat and mass transfer of water vapor assume dominant importance in unsaturated porous media at elevated temperature. Although water vapor fluxes are seldom as large as saturated medium liquid water fluxes, they are important under unsaturated conditions. The major heat transport mechanism for unsaturated porous media at temperatures from 50 to 90/sup 0/C is latent heat flux. The mechanism is nonexistent under saturated conditions but may well control design of unconfined aquifer storage systems. The parametric analysis treats detailed physical phenomena which occur in the flow systems study and demonstrates the temperature and moisture dependence of the transport coefficients of importance. The question of design of an unconfined ATES site is also addressed by considering the effects of aquifer temperature, depth to water table, porous medium flow properties, and surface boundary conditions. Recommendations are made for continuation of this project in its second phase. Both scientific and engineering goals are considered and alternatives are presented.

Childs, S.W.; Malstaff, G.

1982-02-01T23:59:59.000Z

365

Heterogeneous surface fluxes and their effects on the SGP CART site  

SciTech Connect

The treatment of subgrid-scale variations of surface properties and the resultant spatial variations of sensible and latent heat fluxes has received increasing attention in recent years. Mesoscale numerical simulations of highly idealized conditions, in which strong flux contrasts exist between adjacent surfaces, have shown that under some circumstances the secondary circulations induced by land-use differences can significantly affect the properties of the planetary boundary layer (PBL) and the region of the atmosphere above the PBL. At the Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site, the fluxes from different land-surface types are not expected to differ as dramatically as those found in idealized simulations. Although the corresponding effects on the atmosphere should thus be less dramatic, they are still potentially important. From an ARM perspective, in tests of single column models (SCMs) it would be useful to understand the effects of the lower boundary conditions on model performance. We describe here our initial efforts to characterize the variable surface fluxes over the CART site and to assess their effects on the PBL that are important for the performance of SCMs.

Doran, J.C.; Hu, Q.; Hubbe, J.M.; Liljegren, J.C.; Shaw, W.J.; Zhong, S. [Pacific Northwest Lab., Richland, WA (United States); Collatz, G.J. [Goddard Space Flight Center/NASA, Greenbelt, MD (United States)

1995-03-01T23:59:59.000Z

366

Significant Decrease of Uncertainties in Sensible Heat Flux Simulation Using Temporally Variable Aerodynamic Roughness in Two Typical Forest Ecosystems of China  

Science Conference Proceedings (OSTI)

Aerodynamic roughness length zom is an important parameter for reliably simulating surface fluxes. It varies with wind speed, atmospheric stratification, terrain, and other factors. However, it is usually considered a constant. It is known that ...

Yanlian Zhou; Weimin Ju; Xiaomin Sun; Xuefa Wen; Dexin Guan

2012-06-01T23:59:59.000Z

367

Thermal-hydraulic simulation of natural convection decay heat removal in the High Flux Isotope Reactor (HFIR) using RELAP5 and TEMPEST: Part 2, Interpretation and validation of results  

SciTech Connect

The RELAP5/MOD2 code was used to predict the thermal-hydraulic behavior of the HFIR core during decay heat removal through boiling natural circulation. The low system pressure and low mass flux values associated with boiling natural circulation are far from conditions for which RELAP5 is well exercised. Therefore, some simple hand calculations are used herein to establish the physics of the results. The interpretation and validation effort is divided between the time average flow conditions and the time varying flow conditions. The time average flow conditions are evaluated using a lumped parameter model and heat balance. The Martinelli-Nelson correlations are used to model the two-phase pressure drop and void fraction vs flow quality relationship within the core region. Systems of parallel channels are susceptible to both density wave oscillations and pressure drop oscillations. Periodic variations in the mass flux and exit flow quality of individual core channels are predicted by RELAP5. These oscillations are consistent with those observed experimentally and are of the density wave type. The impact of the time varying flow properties on local wall superheat is bounded herein. The conditions necessary for Ledinegg flow excursions are identified. These conditions do not fall within the envelope of decay heat levels relevant to HFIR in boiling natural circulation. 14 refs., 5 figs., 1 tab.

Ruggles, A.E.; Morris, D.G.

1989-01-01T23:59:59.000Z

368

Waste Heat Management Options: Industrial Process Heating Systems  

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

Heat Management Options Heat Management Options Industrial Process Heating Systems By Dr. Arvind C. Thekdi E-mail: athekdi@e3minc.com E3M, Inc. August 20, 2009 2 Source of Waste Heat in Industries * Steam Generation * Fluid Heating * Calcining * Drying * Heat Treating * Metal Heating * Metal and Non-metal Melting * Smelting, agglomeration etc. * Curing and Forming * Other Heating Waste heat is everywhere! Arvind Thekdi, E3M Inc Arvind Thekdi, E3M Inc 3 Waste Heat Sources from Process Heating Equipment * Hot gases - combustion products - Temperature from 300 deg. F. to 3000 deg.F. * Radiation-Convection heat loss - From temperature source of 500 deg. F. to 2500 deg. F. * Sensible-latent heat in heated product - From temperature 400 deg. F. to 2200 deg. F. * Cooling water or other liquids - Temperature from 100 deg. F. to 180 deg. F.

369

Exploiting Latent I/O Asynchrony in Petascale Science Applications  

Science Conference Proceedings (OSTI)

We present a collection of techniques for exploiting latent I/O asynchrony which can substantially improve performance in data-intensive parallel applications. Latent asynchrony refers to an applicationâ??s tolerance for decoupling ancillary operations ...

Patrick Widener; Matthew Wolf; Hasan Abbasi; Scott Mcmanus; Mary Payne; Matthew Barrick; Jack Pulikottil; Patrick Bridges; Karsten Schwan

2011-05-01T23:59:59.000Z

370

Consistent and efficient reconstruction of latent tree models  

E-Print Network (OSTI)

We study the problem of learning a latent tree graphical model where samples are available only from a subset of variables. We propose two consistent and computationally efficient algorithms for learning minimal latent ...

Choi, Myung Jin

371

Latent Cracking of Tantalum - Titanium Welds Due to Hydrogen ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2012. Symposium, Environmentally Assisted Cracking of Materials. Presentation Title, Latent ...

372

Knowledge transfer across multilingual corpora via latent topics  

Science Conference Proceedings (OSTI)

This paper explores bridging the content of two different languages via latent topics. Specifically, we propose a unified probabilistic model to simultaneously model latent topics from bilingual corpora that discuss comparable content and use the topics ... Keywords: cross-lingual knowledge transfer, latent topic models, text categorization

Wim De Smet; Jie Tang; Marie-Francine Moens

2011-05-01T23:59:59.000Z

373

Middle Atmospheric Traveling Waves Forced by Latent and Convective Heating  

Science Conference Proceedings (OSTI)

The excitation and propagation of equatorial planetary waves and inertia-gravity waves were studied by comparing simulations from the comprehensive GFDL troposphere-stratosphere-mesosphere SKYHI general circulation model (GCM) and from a linear ...

Elisa Manzini; Kevin Hamilton

1993-07-01T23:59:59.000Z

374

Relating Convective and Stratiform Rain to Latent Heating  

Science Conference Proceedings (OSTI)

The relationship among surface rainfall, its intensity, and its associated stratiform amount is established by examining observed precipitation data from the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR). The results show ...

Wei-Kuo Tao; Stephen Lang; Xiping Zeng; Shoichi Shige; Yukari Takayabu

2010-04-01T23:59:59.000Z

375

A Climatology of Ocean–Atmosphere Heat Flux Estimates over the Great Barrier Reef and Coral Sea: Implications for Recent Mass Coral Bleaching Events  

Science Conference Proceedings (OSTI)

A regional-scale estimate of the surface heat budget of the Great Barrier Reef and Coral Sea (10°–26°S, 142°–155°E) has been developed for the period 1995–2005 in the hope of understanding the trends of sea surface temperatures and the surface ...

Evan Weller; Manuel Nunez; Gary Meyers; Itsara Masiri

2008-08-01T23:59:59.000Z

376

Rotating Convection Driven by Differential Bottom Heating  

Science Conference Proceedings (OSTI)

Convection experiments were carried out in a rectangular tank as a model of oceanic meridional overturning circulation. The objective was finding a relation between the meridional heat flux and thermal forcing. To make the meridional heat flux ...

Young-Gyu Park; J. A. Whitehead

1999-06-01T23:59:59.000Z

377

Determining the temperature field for cylinder symmetrical heat conduction problems in unsteady heat conduction in finite space  

Science Conference Proceedings (OSTI)

This paper proposes to present a new method to calculate unsteady heat conduction for cylinder symmetrical geometry. We will investigate the situation where the temperature field and heat flux created around a heat source placed in finite space are determined. ... Keywords: Garbai's integral equation, Laplace transformation, determining the temperate field, district heating pipes, geothermal producing pipe, heat flux density, heat loss, heat pump

László Garbai; Szabolcs Méhes

2007-05-01T23:59:59.000Z

378

The Antarctic Zone Flux Experiment  

Science Conference Proceedings (OSTI)

In winter the eastern Weddell Sea in the Atlantic sector of the Southern Ocean hosts some of the most dynamic air-ice-sea interactions found on earth. Sea ice in the region is kept relatively thin by heat flux from below, maintained by upper-...

M. G. McPhee; S. F. Ackley; P. Guest; T. P. Stanton; B. A. Huber; D. G. Martinson; J. H. Morison; R. D. Muench; L. Padman

1996-06-01T23:59:59.000Z

379

Development of an air-cooled, loop-type heat pipe with multiple condensers  

E-Print Network (OSTI)

Thermal management challenges are prevalent in various applications ranging from consumer electronics to high performance computing systems. Heat pipes are capillary-pumped devices that take advantage of the latent heat ...

Kariya, H. Arthur (Harumichi Arthur)

2012-01-01T23:59:59.000Z

380

Disaggregating Cooling Energy Use of Commercial Buildings Into Sensible and Latent Fractions From Whole-Building Monitored Data: Methodology and Advantages  

E-Print Network (OSTI)

In hot and humid climates, where summers are both warm and humid, the latent cooling can be a significant portion of the total cooling load (as much as 40%). Typically the monitored data only includes whole-building heating and cooling energy use and total electric consumption. A method to disaggregate the latent cooling energy use from the measured whole-building heating and cooling energy use would be of particular interest. This paper presents such a method and discusses its benefits. It is shown that the overall heat transfer coefficient including the conduction, infiltration, and ventilation effects of a building, can be evaluated. Subsequently this enables the disaggregation of the total cooling energy use into sensible and latent cooling fractions. The benefits of such a method include: (i) better understanding of the sensible and latent fractions in the total cooling energy use of a building, and (ii) better regression models for energy analysis. In addition to the whole-building cooling and heating energy use and the ambient conditions, the required system parameters include: (i) cold deck supply temperature, (ii) hot deck supply temperature, (iii) mixed air temperature or ventilation rate, (iv) internal gains, and (v) total mass flow rate of the dual duct constant volume system. If continuous measurements of the system parameters are not available, then one-time measurements may be used to disaggregate the latent cooling energy use.

Katipamula, S.; Reddy, T. A.; Claridge, D. E.

1992-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

An experimental and numerical study of the modifications of mixed-layer structure by inhomogeneous surface fluxes and secondary circulations  

SciTech Connect

The problem of scale interactions in the planetary boundary layer (PBL), i.e., how forcing mechanisms of differing spatial and temporal scales affect the properties of the PBL, has been a subject of considerable interest for some time. One aspect of this problem that has received increasing attention in recent years is the representation, in mesoscale and general circulation models. of the effects of subgrid-scale inhomogeneities in surface properties. Differences in sensible and latent heat fluxes between adjacent areas can result in secondary circulations. modifications to the boundary layer structure, and the transport of heat and moisture from one area to another. Despite their potential included on local PBL properties, such effects can not be resolved by numerical models whose scale is too coarse; thus, suitable parameterizations that account for these phenomena are needed. In this paper the authors present some results of wind and temperature measurements over an area with significant variations in surface fluxes on scales of O(10 km). They then use fine resolution numerical simulations to show how synoptic, topographical, and thermal forcing combine to affect the properties of the PBL in the region. Specifically, they consider the relative importance of topography and land-use differences on the generation of secondary circulations and on the depth of the mixed layer, and they show how these effects are modified by synoptic wind fields. Implications for coarser resolution models are also discussed.

Zhong, S.; Doran, J.C.

1994-07-01T23:59:59.000Z

382

Generic Text Summarization Using Probabilistic Latent Semantic Indexing  

E-Print Network (OSTI)

Generic Text Summarization Using Probabilistic Latent Semantic Indexing Harendra Bhandari Graduate School of Information Science Nara Institute of Science and Technology Nara 630-0192, Japan harendra

383

Fast flux locked loop  

DOE Patents (OSTI)

A flux locked loop for providing an electrical feedback signal, the flux locked loop employing radio-frequency components and technology to extend the flux modulation frequency and tracking loop bandwidth. The flux locked loop of the present invention has particularly useful application in read-out electronics for DC SQUID magnetic measurement systems, in which case the electrical signal output by the flux locked loop represents an unknown magnetic flux applied to the DC SQUID.

Ganther, Jr., Kenneth R. (Olathe, KS); Snapp, Lowell D. (Independence, MO)

2002-09-10T23:59:59.000Z

384

Solar heating system  

DOE Patents (OSTI)

An improved solar heating system in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75.degree. to 180.degree. F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing and releasing heat for distribution.

Schreyer, James M. (Oak Ridge, TN); Dorsey, George F. (Concord, TN)

1982-01-01T23:59:59.000Z

385

Improved solar heating systems  

DOE Patents (OSTI)

An improved solar heating system is described in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75 to 180/sup 0/F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing ad releasing heat for distribution.

Schreyer, J.M.; Dorsey, G.F.

1980-05-16T23:59:59.000Z

386

Sequential Inference for Latent Force Models  

E-Print Network (OSTI)

Latent force models (LFMs) are hybrid models combining mechanistic principles with non-parametric components. In this article, we shall show how LFMs can be equivalently formulated and solved using the state variable approach. We shall also show how the Gaussian process prior used in LFMs can be equivalently formulated as a linear statespace model driven by a white noise process and how inference on the resulting model can be efficiently implemented using Kalman filter and smoother. Then we shall show how the recently proposed switching LFM can be reformulated using the state variable approach, and how we can construct a probabilistic model for the switches by formulating a similar switching LFM as a switching linear dynamic system (SLDS). We illustrate the performance of the proposed methodology in simulated scenarios and apply it to inferring the switching points in GPS data collected from car movement data in urban environment.

Hartikainen, Jouni

2012-01-01T23:59:59.000Z

387

Comparison of Four Methods to Estimate Urban Heat Storage  

Science Conference Proceedings (OSTI)

The relative performance of four independent methods to estimate the magnitude and diurnal behavior of net heat storage fluxes (?QS) in a city center is assessed. This heat flux is a significant but understudied component of the urban surface ...

Sarah M. Roberts; T. R. Oke; C. S. B. Grimmond; J. A. Voogt

2006-12-01T23:59:59.000Z

388

Heat Flux Measurement - Requirements, Characterization, and Technologies  

Science Conference Proceedings (OSTI)

Furnace tube failures in utility boilers have persistently been the largest contributor to forced outages on coal-fired generation. Given their impact, the industry has spent considerable resources in understanding their failure modes and developing technology to try to eliminate or at least mitigate the problems they present. In contrast to the historically low emphasis placed on boiler cleaning, there has been substantial interest over the last decade on sootblowing equipment and strategies to mitigate...

2009-07-20T23:59:59.000Z

389

The Response Time of the Temperature of the Equatorial Troposphere to ENSO Heating  

Science Conference Proceedings (OSTI)

Air temperature anomalies, averaged over the troposphere to 200 mb and around the earth from 10°S to 10°N, lag the similarly averaged El Niño–Southern Oscillation (ENSO) atmospheric latent heating anomalies by about one month. Most of the latent ...

Allan J. Clarke; Kwang-Y. Kim

2005-12-01T23:59:59.000Z

390

Global models of document structure using latent permutations  

E-Print Network (OSTI)

We present a novel Bayesian topic model for learning discourse-level document structure. Our model leverages insights from discourse theory to constrain latent topic assignments in a way that reflects the underlying ...

Chen, Harr

391

Energy flux limitation by tame turbulence  

SciTech Connect

A quasi-linear theory of energy flux limitation by ion acoustic turbulence is presented. This distribution function is modelled by a Maxwellian plus an additional piece which carries a heat flux Q. By taking the fourth moment of the Vlasov equation one finds the anomalous thermal conductivity K approximately 3 v/sub e/ delta/sub De/ (e phi/T/sub e/)$sup -2$. Other moments treated self-consistently include anomalous ion heating, electron cooling, current generation and enhanced inverse bremsstrahlung due to the nonthermal ion fluctuations. (auth)

Manheimer, W.M.

1975-11-01T23:59:59.000Z

392

On the Significance of the Sensible Heat Supply from the Ocean in the Maintenance of the Mean Baroclinicity along Storm Tracks  

Science Conference Proceedings (OSTI)

The relative importance between the sensible heat supply from the ocean and latent heating is assessed for the maintenance of near-surface mean baroclinicity in the major storm-track regions, by analyzing steady linear responses of a planetary ...

Daisuke Hotta; Hisashi Nakamura

2011-07-01T23:59:59.000Z

393

Regional Weather Patterns during Anomalous Air–Sea Fluxes at the Kuroshio Extension Observatory (KEO)  

Science Conference Proceedings (OSTI)

The weather patterns during periods of anomalous surface fluxes in the Kuroshio recirculation gyre of the western North Pacific are documented. Separate analyses are carried out for the cold season (October– March) when the net surface heat flux ...

Nicholas A. Bond; Meghan F. Cronin

2008-04-01T23:59:59.000Z

394

Seasonal and Interannual Variability in a Model of the Mediterranean under Derived Flux Forcing  

Science Conference Proceedings (OSTI)

A 100-yr integration of a Mediterranean Sea model is performed with surface restoring to monthly varying T, S, followed by 100 years of integration with surface fluxes of heat and freshwater alone. The fluxes are diagnosed from the restoring ...

Paul G. Myers; Keith Haines

2000-05-01T23:59:59.000Z

395

Air–Sea Fluxes over the Gulf Stream Region: Atmospheric Controls and Trends  

Science Conference Proceedings (OSTI)

The intraseasonal variability of turbulent surface heat fluxes over the Gulf Stream extension and subtropical mode water regions of the North Atlantic, and long-term trends in these fluxes, are explored using NCEP–NCAR reanalysis. Wintertime ...

Jeffrey Shaman; R. M. Samelson; Eric Skyllingstad

2010-05-01T23:59:59.000Z

396

Combining Satellite Microwave Radiometer and Radar Observations to Estimate Atmospheric Heating Profiles  

Science Conference Proceedings (OSTI)

In this study, satellite passive microwave sensor observations from the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) are utilized to make estimates of latent + eddy sensible heating rates (Q1 ? QR) where Q1 is the apparent ...

Mircea Grecu; William S. Olson; Chung-Lin Shie; Tristan S. L’Ecuyer; Wei-Kuo Tao

2009-12-01T23:59:59.000Z

397

Geometrical vector flux sinks and ideal flux concentrators  

SciTech Connect

The description of ideal flux concentrators as shapes that do not disturb the geometrical vector flux field is extended to all the known types of ideal flux concentrators. This is accomplished, in part, by the introduction of vector flux sinks.

Greenman, P.

1981-06-01T23:59:59.000Z

398

A critical evaluation of the upper ocean heat budget in the Climate Forecast System Reanalysis data for the south central equatorial Pacific  

SciTech Connect

Coupled ocean-atmospheric models suffer from the common bias of a spurious rain belt south of the central equatorial Pacific throughout the year. Observational constraints on key processes responsible for this bias are scarce. The recently available reanalysis from a coupled model system for the National Centers for Environmental Prediction (NCEP) Climate Forecast System Reanalysis (CFSR) data is a potential benchmark for climate models in this region. Its suitability for model evaluation and validation, however, needs to be established. This paper examines the mixed layer heat budget and the ocean surface currents - key factors for the sea surface temperature control in the double Inter-Tropical Convergence Zone in the central Pacific - from 5{sup o}S to 10{sup o}S and 170{sup o}E to 150{sup o}W. Two independent approaches are used. The first approach is through comparison of CFSR data with collocated station observations from field experiments; the second is through the residual analysis of the heat budget of the mixed layer. We show that the CFSR overestimates the net surface flux in this region by 23 W m{sup -2}. The overestimated net surface flux is mainly due to an even larger overestimation of shortwave radiation by 44 W m{sup -2}, which is compensated by a surface latent heat flux overestimated by 14 W m{sup -2}. However, the quality of surface currents and the associated oceanic heat transport in CFSR are not compromised by the surface flux biases, and they agree with the best available estimates. The uncertainties of the observational data from field experiments are also briefly discussed in the present study.

Liu H.; Lin W.; Liu, X.; Zhang, M.

2011-08-26T23:59:59.000Z

399

Molten Mold Flux Technology for Continuous Casting of the ULC ...  

Science Conference Proceedings (OSTI)

Heat flux from the molten steel to the cupper plate of the casting mold was .... of Conventional and High Niobium API 5L X80 Line Pipe Steel Using EBSD.

400

A Nonlinear Statistical Model of Turbulent Air–Sea Fluxes  

Science Conference Proceedings (OSTI)

Most of the bulk algorithms used to calculate turbulent air–sea fluxes of momentum and heat are iterative algorithms whose convergence is slow and not always achieved. To avoid these drawbacks that are critical when large datasets must be ...

Denis Bourras; Gilles Reverdin; Guy Caniaux; Sophie Belamari

2007-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Scaling Baroclinic Eddy Fluxes: Vortices and Energy Balance  

Science Conference Proceedings (OSTI)

The eddy heat flux generated by the statistically equilibrated baroclinic instability of a uniform, horizontal temperature gradient is studied using a two-mode f-plane quasigeostrophic model. An overview of the dependence of the eddy diffusivity ...

Andrew F. Thompson; William R. Young

2006-04-01T23:59:59.000Z

402

Regional Variations of Moist Static Energy Flux into the Arctic  

Science Conference Proceedings (OSTI)

The authors investigate the climmological heating of the Arctic by the atmospheric moist static energy (MSE) flux from lower latitudes based on 25 years (November 1964–1989) of the GFDL dataset. During the five month winter period (NDJFM) the ...

James E. Overland; Philip Turet; Abraham H. Oort

1996-01-01T23:59:59.000Z

403

Structural Analysis of Airborne Flux Estimates over a Region  

Science Conference Proceedings (OSTI)

Aircraft-based observations of turbulence fields of velocity, moisture, and temperature are used to study coherent turbulent structures that dominate turbulent transfer of moisture and heat above three different eco-systems. Flux traces are ...

Paulo Caramori; Peter Schuepp; Raymond Desjardins; Ian MacPherson

1994-05-01T23:59:59.000Z

404

Spheromak reactor with poloidal flux-amplifying transformer  

DOE Patents (OSTI)

An inductive transformer in the form of a solenoidal coils aligned along the major axis of a flux core induces poloidal flux along the flux core's axis. The current in the solenoidal coil is then reversed resulting in a poloidal flux swing and the conversion of a portion of the poloidal flux to a toroidal flux in generating a spheromak plasma wherein equilibrium approaches a force-free, minimum Taylor state during plasma formation, independent of the initial conditions or details of the formation. The spheromak plasma is sustained with the Taylor state maintained by oscillating the currents in the poloidal and toroidal field coils within the plasma-forming flux core. The poloidal flux transformer may be used either as an amplifier stage in a moving plasma reactor scenario for initial production of a spheromak plasma or as a method for sustaining a stationary plasma and further heating it. The solenoidal coil embodiment of the poloidal flux transformer can alternately be used in combination with a center conductive cylinder aligned along the length and outside of the solenoidal coil. This poloidal flux-amplifying inductive transformer approach allows for a relaxation of demanding current carrying requirements on the spheromak reactor's flux core, reduces plasma contamination arising from high voltage electrode discharge, and improves the efficiency of poloidal flux injection.

Furth, Harold P. (Princeton, NJ); Janos, Alan C. (East Windsor, NJ); Uyama, Tadao (Osaka, JP); Yamada, Masaaki (Lawrenceville, NJ)

1987-01-01T23:59:59.000Z

405

FLUX MEASUREMENTS FROM A TALL TOWER IN A COMPLEX LANDSCAPE  

Science Conference Proceedings (OSTI)

The accuracy and representativeness of flux measurements from a tall tower in a complex landscape was assessed by examining the vertical and sector variability of the ratio of wind speed to momentum flux and the ratio of vertical advective to eddy flux of heat. The 30-60 m ratios were consistent with theoretical predictions which indicate well mixed flux footprints. Some variation with sector was observed that were consistent with upstream roughness. Vertical advection was negligible compared with vertical flux except for a few sectors at night. This implies minor influence from internal boundary layers. Flux accuracy is a function of sector and stability but 30-60 m fluxes were found to be generally representative of the surrounding landscape. This paper will study flux data from a 300 m tower, with 4 levels of instruments, in a complex landscape. The surrounding landscape will be characterized in terms of the variation in the ratio of mean wind speed to momentum flux as a function of height and wind direction. The importance of local advection will be assessed by comparing vertical advection with eddy fluxes for momentum and heat.

Kurzeja, R.; Weber, A.; Chiswell, S.; Parker, M.

2010-07-22T23:59:59.000Z

406

Multi-Scale Kernel Latent Variable Models for Nonlinear Time Series Pattern Matching  

Science Conference Proceedings (OSTI)

In this paper we propose a method for nonlinear time series pattern matching: "Multi-Scale Kernel Latent Variable (MSKLV) models". The pattern matching methodology includes multi-scale analysis using wavelet decomposition of time series and finding latent ...

B. Venkataramana Kini; C. Chandra Sekhar

2008-01-01T23:59:59.000Z

407

Gas heat transfer in a heated vertical channel under deteriorated turbulent heat transfer regime  

E-Print Network (OSTI)

Passive cooling via natural circulation of gas after a loss of coolant (LOCA) accident is one of the major goals of the Gas-cooled Fast Reactor (GFR). Due to its high surface heat flux and low coolant velocities under ...

Lee, Jeongik

2007-01-01T23:59:59.000Z

408

Gas Heat Transfer in a Heated Vertical Channel under Deteriorated Turbulent Heat Transfer Regime  

E-Print Network (OSTI)

Passive cooling via natural circulation of gas after a loss of coolant (LOCA) accident is one of the major goals of the Gas-cooled Fast Reactor (GFR). Due to its high surface heat flux and low coolant velocities under ...

Lee, Jeongik

409

ON THE ERUPTION OF CORONAL FLUX ROPES  

SciTech Connect

We present three-dimensional MHD simulations of the evolution of the magnetic field in the corona where the emergence of a twisted magnetic flux tube is driven at the lower boundary into a pre-existing coronal potential arcade field. Through a sequence of simulations in which we vary the amount of twisted flux transported into the corona before the emergence is stopped, we investigate the conditions that lead to a dynamic eruption of the resulting coronal flux rope. It is found that the critical condition for the onset of eruption is for the center of the flux rope to reach a critical height at which the corresponding potential field declines with height at a sufficiently steep rate, consistent with the onset of the torus instability of the flux rope. In some cases, immediately after the emergence is stopped, the coronal flux rope first settles into a quasi-static rise with an underlying sigmoid-shaped current layer developing. Preferential heating of field lines going through this current layer may give rise to the observed quiescent X-ray sigmoid loops before eruption. Reconnections in the current layer during the initial quasi-static stage is found to add detached flux to the coronal flux rope, allowing it to rise quasi-statically to the critical height and dynamic eruption of the flux rope then ensues. By identifying field lines whose tops are in the most intense part of the current layer during the eruption, we deduce the evolution and morphology of the post-flare X-ray loops and the flare ribbons at their footpoints.

Fan, Y. [High Altitude Observatory, National Center for Atmospheric Research, 3080 Center Green Drive, Boulder, CO 80301 (United States)

2010-08-10T23:59:59.000Z

410

Thermal analysis of heat storage canisters for a solar dynamic, space power system  

DOE Green Energy (OSTI)

A thermal analysis was performed of a thermal energy storage canister of a type suggested for use in a solar receiver for an orbiting Brayton cycle power system. Energy storage for the eclipse portion of the cycle is provided by the latent heat of a eutectic mixture of LiF and CaF/sub 2/ contained in the canister. The chief motivation for the study is the prediction of vapor void effects on temperature profiles and the identification of possible differences between ground test data and projected behavior in microgravity. The first phase of this study is based on a two-dimensional, cylindrical coordinates model using an interim procedure for describing void behavior in 1/minus/g and microgravity. The thermal anaylsis includes the effects of solidification front behavior, conduction in liquid/solid salt and canister materials, void growth and shrinkage, radiant heat transfer across the void, and convection in the melt due to Marangoni-induced flow and, in 1/minus/g, flow due to density gradients. A number of significant differences between 1/minus/g and 0/minus/g behavior were found. These resulted from differences in void location relative to the maximum heat flux and a significantly smaller effective conductance in 0/minus/g due to the absence of gravity-induced convection.

Wichner, R.P.; Solomon, A.D.; Drake, J.B.; Williams, P.T.

1988-04-01T23:59:59.000Z

411

Are ghost surfaces and quadratic-flux-minimizing surfaces the same?  

E-Print Network (OSTI)

12 2 2 10 || parallel diffusion dominates perpendicular diffusio solved numerically on grid 2 2 heat, 1 Nov 2009, Atlanta, GA, USA ( ) -10 || ||heat transport is anisotropic: 0 with / =10 if nested flux

Hudson, Stuart

412

Predictive discrete latent factor models for large scale dyadic data  

Science Conference Proceedings (OSTI)

We propose a novel statistical method to predict large scale dyadic response variables in the presence of covariate information. Our approach simultaneously incorporates the effect of covariates and estimates local structure that is induced by interactions ... Keywords: co-clustering, dyadic data, generalized linear regression, latent factor modeling

Deepak Agarwal; Srujana Merugu

2007-08-01T23:59:59.000Z

413

Fast structure learning in generalized stochastic processes with latent factors  

Science Conference Proceedings (OSTI)

Understanding and quantifying the impact of unobserved processes is one of the major challenges of analyzing multivariate time series data. In this paper, we analyze a flexible stochastic process model, the generalized linear auto-regressive process ... Keywords: generalized linear models, latent factors, time series analysis

Mohammad Taha Bahadori, Yan Liu, Eric P. Xing

2013-08-01T23:59:59.000Z

414

Predictive Inference Using Latent Variables with Lynne Steuerle Schofield  

E-Print Network (OSTI)

institutionally-generated PV methodology and find it applies with greater generality than shown previously. When latent proficiency is an independent variable, we show that the standard institu- tional PV methodology with high reliability and precision, due to their efficient use of assessment data. Econometricians, policy

415

Two-dimensional computational fluid dynamics and conduction simulations of heat transfer in window frames with internal cavities - Part 1: Cavities only  

E-Print Network (OSTI)

of heat fluxes from CFD and conduction simulations for theapproach to solve the conduction heat-transfer equation. TheFluid Dynamics and Conduction Simulations of Heat Transfer

Gustavsen, Arild; Kohler, Christian; Arasteh, Dariush; Curcija, Dragan

2003-01-01T23:59:59.000Z

416

Exploring the Limits of Boiling and Evaporative Heat Transfer Using Micro/Nano Structures  

E-Print Network (OSTI)

8) (2006) [9] A. Faghri, Heat pipe science and technology,investigations on micro heat pipes, Int J Energ Res, 31(6-investigation of a high flux heat pipe heat sink, J Electron

Lu, Ming-Chang

2010-01-01T23:59:59.000Z

417

Concentration with uniform flux  

SciTech Connect

A modification of a parabolic cylinder concentrator is developed to procedure uniform flux. The controlling surface equation is given. A three-dimensional ray-trace technique is used to obtain the shape of the image at the focal plane of a thin slice of the mirror. Also, the concentration distribution for uniform flux is given. 1 references, 7 figures.

Not Available

1986-01-01T23:59:59.000Z

418

The Mean Along-Isobath Heat and Salt Balances over the Middle Atlantic Bight Continental Shelf  

Science Conference Proceedings (OSTI)

The mean heat and salt balances over the Middle Atlantic Bight continental shelf are investigated by testing the hypothesis that surface fluxes of heat or freshwater are balanced by along-isobath fluxes resulting from the mean, depth-averaged, ...

Steven J. Lentz

2010-05-01T23:59:59.000Z

419

HEAT TRANSFER METHOD  

DOE Patents (OSTI)

A method is given for increasing burn-out heat fluxes under nucleate boiling conditions in heat exchanger tubes without incurring an increase in pumping power requirements. This increase is achieved by utilizing a spinning flow having a rotational velocity sufficient to produce a centrifugal acceleration of at least 10,000 g at the tube wall. At this acceleration the heat-transfer rate at burn out is nearly twice the rate which can be achieved in a similar tube utilizing axial flow at the same pumping power. At higher accelerations the improvement over axial flow is greater, and heat fluxes in excess of 50 x 10/sup 6/ Btu/hr/sq ft can be achieved.

Gambill, W.R.; Greene, N.D.

1960-08-30T23:59:59.000Z

420

Plasma momentum meter for momentum flux measurements  

DOE Patents (OSTI)

Invention comprises an instrument in which momentum flux onto a biasable target plate is transferred via a suspended quartz tube onto a sensitive force transducer--a capacitance-type pressure gauge. The transducer is protected from thermal damage, arcing and sputtering, and materials used in the target and pendulum are electrically insulating, rigid even at elevated temperatures, and have low thermal conductivity. The instrument enables measurement of small forces (10.sup.-5 to 10.sup.3 N) accompanied by high heat fluxes which are transmitted by energetic particles with 10's of eV of kinetic energy in a intense magnetic field and pulsed plasma environment.

Zonca, Fulvio (Rome, IT); Cohen, Samuel A. (Hopewell, NJ); Bennett, Timothy (Princeton, NJ); Timberlake, John R. (Allentown, NJ)

1993-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Plasma momentum meter for momentum flux measurements  

DOE Patents (OSTI)

Invention comprises an instrument in which momentum flux onto a biasable target plate is transferred via a suspended quartz tube onto a sensitive force transducer - a capacitance-type pressure gauge. The transducer is protected from thermal damage, arcing and sputtering, and materials used in the target and pendulum are electrically insulating, rigid even at elevated temperatures, and have low thermal conductivity. The instrument enables measurement of small forces (10{sup {minus}5} to 10{sup 3} N) accompanied by high heat fluxes which are transmitted by energetic particles with 10`s of eV of kinetic energy in an intense magnetic field and pulsed plasma environment.

Zonca, F.; Cohen, S.A.; Bennett, T.; Timberlake, J.R.

1991-12-31T23:59:59.000Z

422

Plasma momentum meter for momentum flux measurements  

DOE Patents (OSTI)

Invention comprises an instrument in which momentum flux onto a biasable target plate is transferred via a suspended quartz tube onto a sensitive force transducer - a capacitance-type pressure gauge. The transducer is protected from thermal damage, arcing and sputtering, and materials used in the target and pendulum are electrically insulating, rigid even at elevated temperatures, and have low thermal conductivity. The instrument enables measurement of small forces (10[sup [minus]5] to 10[sup 3] N) accompanied by high heat fluxes which are transmitted by energetic particles with 10's of eV of kinetic energy in an intense magnetic field and pulsed plasma environment.

Zonca, F.; Cohen, S.A.; Bennett, T.; Timberlake, J.R.

1991-01-01T23:59:59.000Z

423

A Potential Vorticity-Based Study of the Role of Diabatic Heating and Friction in a Numerically Simulated Baroclinic Cyclone  

Science Conference Proceedings (OSTI)

A particularly intense case of western Atlantic baroclinic cyclogenesis was investigated in this study. Specifically, the roles of latent heat of condensation and surface friction were examined from the potential vorticity or “PV thinking” ...

Mark T. Stoelinga

1996-05-01T23:59:59.000Z

424

Exploring the Limits of Boiling and Evaporative Heat Transfer Using Micro/Nano Structures.  

E-Print Network (OSTI)

??This dissertation presents a study exploring the limits of phase-change heat transfer with the aim of enhancing critical heat flux (CHF) in pool boiling and… (more)

Lu, Ming-Chang

2010-01-01T23:59:59.000Z

425

Computing Solar Absolute Fluxes  

E-Print Network (OSTI)

Computed color indices and spectral shapes for individual stars are routinely compared with observations for essentially all spectral types, but absolute fluxes are rarely tested. We can confront observed irradiances with the predictions from model atmospheres for a few stars with accurate angular diameter measurements, notably the Sun. Previous calculations have been hampered by inconsistencies and the use of outdated atomic data and abundances. I provide here a progress report on our current efforts to compute absolute fluxes for solar model photospheres. Uncertainties in the solar composition constitute a significant source of error in computing solar radiative fluxes.

Prieto, Carlos Allende

2007-01-01T23:59:59.000Z

426

Computing Solar Absolute Fluxes  

E-Print Network (OSTI)

Computed color indices and spectral shapes for individual stars are routinely compared with observations for essentially all spectral types, but absolute fluxes are rarely tested. We can confront observed irradiances with the predictions from model atmospheres for a few stars with accurate angular diameter measurements, notably the Sun. Previous calculations have been hampered by inconsistencies and the use of outdated atomic data and abundances. I provide here a progress report on our current efforts to compute absolute fluxes for solar model photospheres. Uncertainties in the solar composition constitute a significant source of error in computing solar radiative fluxes.

Carlos Allende Prieto

2007-09-14T23:59:59.000Z

427

Splitting schemes for hyperbolic heat conduction equation  

E-Print Network (OSTI)

Rapid processes of heat transfer are not described by the standard heat conduction equation. To take into account a finite velocity of heat transfer, we use the hyperbolic model of heat conduction, which is connected with the relaxation of heat fluxes. In this case, the mathematical model is based on a hyperbolic equation of second order or a system of equations for the temperature and heat fluxes. In this paper we construct for the hyperbolic heat conduction equation the additive schemes of splitting with respect to directions. Unconditional stability of locally one-dimensional splitting schemes is established. New splitting schemes are proposed and studied for a system of equations written in terms of the temperature and heat fluxes.

Vabishchevich, Petr N

2010-01-01T23:59:59.000Z

428

Determining Reactor Neutrino Flux  

E-Print Network (OSTI)

Flux is an important source of uncertainties for a reactor neutrino experiment. It is determined from thermal power measurements, reactor core simulation, and knowledge of neutrino spectra of fuel isotopes. Past reactor neutrino experiments have determined the flux to (2-3)% precision. Precision measurements of mixing angle $\\theta_{13}$ by reactor neutrino experiments in the coming years will use near-far detector configurations. Most uncertainties from reactor will be canceled out. Understanding of the correlation of uncertainties is required for $\\theta_{13}$ experiments. Precise determination of reactor neutrino flux will also improve the sensitivity of the non-proliferation monitoring and future reactor experiments. We will discuss the flux calculation and recent progresses.

Cao, Jun

2011-01-01T23:59:59.000Z

429

Determining Reactor Neutrino Flux  

E-Print Network (OSTI)

Flux is an important source of uncertainties for a reactor neutrino experiment. It is determined from thermal power measurements, reactor core simulation, and knowledge of neutrino spectra of fuel isotopes. Past reactor neutrino experiments have determined the flux to (2-3)% precision. Precision measurements of mixing angle $\\theta_{13}$ by reactor neutrino experiments in the coming years will use near-far detector configurations. Most uncertainties from reactor will be canceled out. Understanding of the correlation of uncertainties is required for $\\theta_{13}$ experiments. Precise determination of reactor neutrino flux will also improve the sensitivity of the non-proliferation monitoring and future reactor experiments. We will discuss the flux calculation and recent progresses.

Jun Cao

2011-01-12T23:59:59.000Z

430

Regional climate effects of irrigation and urbanization in the western united states: a model intercomparison  

E-Print Network (OSTI)

In the two northern grid cells, sensible heat flux decreasedthe two southern grid cells sensible heat flux increased andgrid cells that were irrigated in Figure 5. January and August latent heat

2006-01-01T23:59:59.000Z

431

Heat pipe array heat exchanger  

DOE Patents (OSTI)

A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

Reimann, Robert C. (Lafayette, NY)

1987-08-25T23:59:59.000Z

432

Airborne measurements of mass, momentum, and energy fluxes for the boardman-arm regional flux experiment-1991. Preliminary data release. Technical memo  

SciTech Connect

During 2 - 19 June 1991 the Atmospheric Turbulence and Diffusion Division of NOAA measured flux densities of mass, momentum, and energy from an airplane in support of DOE's Atmospheric Radiation Measurement (ARM) program. Over 507 horizontal flux transects were completed, along with 24 vertical atmospheric profiles, during the 93 flight hours. Flux transects passed over both irrigated farmland and steppe. The report describes the variation in wind, radiation, and surface temperature, along with exchange of mass (CO2, H2O, and O3), momentum, and energy as observed along the transects. Airborne measurements are compared with those from flux towers in wheat, corn, and steppe. In general, the measurements correspond well. The largest difference occurs at the steppe tower, with stronger heat fluxes reported by the tower. This discrepancy increases as heat flux increases. The cause may be a significant vertical flux divergence or an inconsistant specification of the mean state.

Crawford, T.L.; Dobosy, R.J.; Birdwell, K.R.

1993-04-01T23:59:59.000Z

433

Fundamental heat transfer experiments of heat pipes for turbine cooling  

SciTech Connect

Fundamental heat transfer experiments were carried out for three kinds of heat pipes that may be applied to turbine cooling in future aero-engines. In the turbine cooling system with a heat pipe, heat transfer rate and start-up time of the heat pipe are the most important performance criteria to evaluate and compare with conventional cooling methods. Three heat pipes are considered, called heat pipe A, B, and C, respectively. All heat pipes have a stainless steel shell and nickel sintered powder metal wick. Sodium (Na) was the working fluid for heat pipes A and B; heat pipe C used eutectic sodium-potassium (NaK). Heat pipes B and C included noncondensible gas for rapid start-up. There were fins on the cooling section of heat pipes. In the experiments, an infrared image furnace supplied heat to the heat pipe simulating turbine blade surface conditions. In the results, heat pipe B demonstrated the highest heat flux of 17 to 20 W/cm{sup 2}. The start-up time was about 6 minutes for heat pipe B and about 6 minutes for heat pipe A. Thus, adding noncondensible gas effectively reduced start-up time. Although NaK is a liquid phase at room temperature, the start-up time of heat pipe C (about 7 to 8 minutes) was not shorter than the heat pipe B. The effect of a gravitational force on heat pipe performance was also estimated by inclining the heat pipe at an angle of 90 deg. There was no significant gravitational dependence on heat transport for heat pipes including noncondensible gas.

Yamawaki, S. [Ishikawajima-Harima Heavy Industries Co., Ltd., Tokyo (Japan); Yoshida, T.; Taki, M.; Mimura, F. [National Aerospace Lab., Tokyo (Japan)

1998-07-01T23:59:59.000Z

434

Enhanced heat transfer for thermionic power modules  

DOE Green Energy (OSTI)

The thermionic power module is capable of operating at very high heat fluxes, which in turn serve to reduce capital costs. The most efficient operation also requires uniform heat fluxes. The development of enhanced heat transfer systems is required to meet the demand for high heat fluxes (>20 w/cm/sup 2/) at high temperatures (>1500K) which advanced thermionic power modules place upon combustion systems. Energy transfer from the hot combustion gases may take place by convection, radiation, or a combination of radiation and convection. Enhanced convective heat transfer with a jet impingement system has been demonstrated in a thermionic converter. The recently-developed cellular ceramic radiative heat transfer system has also been applied to a thermionic converter. By comparing the jet impingement and cellular ceramic radiative heat transfer systems, an appropriate system may be selected for utilization in advanced thermionic power modules. Results are reported.

Johnson, D.C.

1981-07-01T23:59:59.000Z

435

Flux lattices reformulated  

E-Print Network (OSTI)

We theoretically explore the optical flux lattices produced for ultra-cold atoms subject to laser fields where both the atom-light coupling and the effective detuning are spatially periodic. We analyze the geometric vector potential and the magnetic flux it generates, as well as the accompanying geometric scalar potential. We show how to understand the gauge-dependent Aharonov-Bohm singularities in the vector potential, and calculate the continuous magnetic flux through the elementary cell in terms of these singularities. The analysis is illustrated with a square optical flux lattice. We conclude with an explicit laser configuration yielding such a lattice using a set of five properly chosen beams with two counterpropagating pairs (one along the x axes and the other y axes), together with a single beam along the z axis. We show that this lattice is not phase-stable, and identify the one phase-difference that affects the magnetic flux. Thus armed with realistic laser setup, we directly compute the Chern number...

Juzeli?nas, G

2012-01-01T23:59:59.000Z

436

Dynamic van der Waals Theory of Two-Phase Fluids in Heat Flow Akira Onuki  

E-Print Network (OSTI)

Dynamic van der Waals Theory of Two-Phase Fluids in Heat Flow Akira Onuki Department of Physics as a functional of the order parameter and the energy density. Let us consider one-component fluids, where-component fluids the effect is drastically altered due to latent heat generation or absorption at the interface [12

437

Estimating Monthly Averaged Air-Sea Transfers of Heat and Momentum Using the Bulk Aerodynamic Method  

Science Conference Proceedings (OSTI)

Air-sea transfers of sensible heat, latent heat and momentum are computed from 25 years of middle-latitude and subtropical ocean weather ship data in the North Atlantic and North Pacific using the bulk aerodynamic method. The results show that ...

Steven K. Esbensen; Richard W. Reynolds

1981-04-01T23:59:59.000Z

438

HIGH FLUX ISOTOPE REACTOR PRELIMINARY DESIGN STUDY  

SciTech Connect

A comparison of possible types of research reactors for the production of transplutonium elements and other isotopes indicates that a flux-trap reactor consisting of a beryllium-reflecteds light-water-cooled annular fuel region surrounding a light-water island provides the required thermal neutron fluxes at minimum cost. The preliminary desigu of such a reactor was carried out on the basis of a parametric study of the effect of dimensions of the island and fuel regions heat removal rates, and fuel loading on the achievable thermal neutmn fluxes in the island and reflector. The results indicate that a 12- to 14-cm- diam. island provides the maximum flux for a given power density. This is in good agreement with the US8R critical experiments. Heat removal calculations indicate that average power densities up to 3.9 Mw/liter are achievable with H/ sub 2/O-cooled, platetype fuel elements if the system is pressurized to 650 psi to prevent surface boiling. On this basis, 100 Mw of heat can be removed from a 14-cm-ID x 36-cm-OD x 30.5-cm-long fuel regions resulting in a thermal neutron flux of 3 x 10/sup 15/ in the island after insertion of 100 g of Cm/sup 244/ or equivalent. The resulting production of Cf/sup 252/ amounts to 65 mg for a 1 1/2- year irradiation. Operation of the reactor at the more conservative level of 67 Mw, providing an irradiation flux of 2 x 10/sup 15/ in the islands will result in the production of 35 mg of Cf/sup 252/ per 18 months from 100 g of Cm/sup 244/. A development program is proposed to answer the question of the feasibility of the higher power operation. In addition to the central irradiation facility for heavyelement productions the HFIR contains ten hydraulic rabbit tubes passing through the beryllium reflector for isotope production and four beam holes for basic research, Preliminary estimates indicate that the cost of the facility, designed for an operating power level of 100 Mw, will be approximately 2 million. (auth)

Lane, J.A.; Cheverton, R.D.; Claiborne, G.C.; Cole, T.E.; Gambill, W.R.; Gill, J.P.; Hilvety, N.; McWherther, J.R.; Vroom, D.W.

1959-03-20T23:59:59.000Z

439

Boosted Fast Flux Loop Alternative Cooling Assessment  

Science Conference Proceedings (OSTI)

The Gas Test Loop (GTL) Project was instituted to develop the means for conducting fast neutron irradiation tests in a domestic radiation facility. It made use of booster fuel to achieve the high neutron flux, a hafnium thermal neutron absorber to attain the high fast-to-thermal flux ratio, a mixed gas temperature control system for maintaining experiment temperatures, and a compressed gas cooling system to remove heat from the experiment capsules and the hafnium thermal neutron absorber. This GTL system was determined to provide a fast (E > 0.1 MeV) flux greater than 1.0E+15 n/cm2-s with a fast-to-thermal flux ratio in the vicinity of 40. However, the estimated system acquisition cost from earlier studies was deemed to be high. That cost was strongly influenced by the compressed gas cooling system for experiment heat removal. Designers were challenged to find a less expensive way to achieve the required cooling. This report documents the results of the investigation leading to an alternatively cooled configuration, referred to now as the Boosted Fast Flux Loop (BFFL). This configuration relies on a composite material comprised of hafnium aluminide (Al3Hf) in an aluminum matrix to transfer heat from the experiment to pressurized water cooling channels while at the same time providing absorption of thermal neutrons. Investigations into the performance this configuration might achieve showed that it should perform at least as well as its gas-cooled predecessor. Physics calculations indicated that the fast neutron flux averaged over the central 40 cm (16 inches) relative to ATR core mid-plane in irradiation spaces would be about 1.04E+15 n/cm2-s. The fast-to-thermal flux ratio would be in excess of 40. Further, the particular configuration of cooling channels was relatively unimportant compared with the total amount of water in the apparatus in determining performance. Thermal analyses conducted on a candidate configuration showed the design of the water coolant and Al-Hf alloy heat sink system is capable of maintaining all system components below their maximum temperature limits. The maximum temperature of this conduction cooling system, 224.2°C (435.6 °F) occurs in a small, localized region in the heat sink structure near the core mid-plane. The total coolant flow rate requirement for this configuration is 207 L/min (54.7 gpm). The calculated Flow Instability Ratio and Departure from Nucleate Boiling Ratio for this configuration under nominal conditions are 6.5 and 8.0, respectively, which safely exceed the minimum values of 2.0. Materials and fabrication issues inspection revealed that the neutron absorber would probably best be made from powdered Al3Hf mixed with aluminum powder and extruded or hot isostatically pressed. Although Al3Hf has not been specifically studied extensively, its mechanical and chemical properties should be very much like Al3Zr, which has been studied. Its behavior under irradiation should be very satisfactory, and resistance to corrosion will be investigated to a limited extent in planned miniplate irradiation tests in ATR. Pressurized water systems needed to effect heat removal are already available in the ATR complex, and mixed gas temperature control systems needed to trim experiment temperatures have been engineered and need only be fabricated and installed. In sum, it appears the alternately cooled configuration arrived at can be very successful. The cost estimate for this configuration indicates to

Glen R. Longhurst; Donna Post Guillen; James R. Parry; Douglas L. Porter; Bruce W. Wallace

2007-08-01T23:59:59.000Z

440

Industrial Heat Pump Case Study  

E-Print Network (OSTI)

An open-cycle heat pump was retrofitted to a single-effect, recirculating-type evaporator used for reducing the water content of whey (a liquid by-product from cheese production). The purpose of the retrofit was to reduce the energy costs associated with operating the evaporator. The open-cycle heat pump design uses an electrically driven centrifugal compressor to recover the latent heat of the water vapor generated by the evaporator. (Steam was the original heat source but is now only needed for start-up.) This concept is sometimes called mechanical vapor compression (MVC) or mechanical vapor recompression (MVR). A variety of engineering issues have to be resolved to integrate a heat pump into an evaporator system. This paper identifies key issues and describes how they were resolved for this particular process. Issues include choice of compressor, motor selection, control strategy, impact of heat pump on heat exchanger surface area requirements and related issues, and methods for protecting the compressor from surge, droplet ingestion, and other hazards.

Wagner, J. R.; Brush, F. C.

1985-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Heat or cold storage composition containing a hydrated hydraulic cement  

SciTech Connect

A polyphase composition for the storage of heat or cold is disclosed that utlizes the latent heat of fusion of a salt hydrate continuous phase intimately intermixed with a hydrated hydraulic cement continuous phase and wherein said continuous phases are optionally in contact with a discontinuous crystalline phase comprising a nucleating component and wherein the composition is enveloped, contained, or packaged within a vapor impermeable material.

Boardman, B.J.

1981-07-07T23:59:59.000Z

442

Heat pipe heat amplifier  

SciTech Connect

In a heat pipe combination consisting of a common condenser section with evaporator sections at either end, two working fluids of different vapor pressures are employed to effectively form two heat pipe sections within the same cavity to support an amplifier mode of operation.

Arcella, F.G.

1978-08-15T23:59:59.000Z

443

Meridional Heat Transport Variability at 26.5°N in the North Atlantic  

Science Conference Proceedings (OSTI)

Data from almost five years of current meter moorings located across the Bahamas Escarpment at 26.5°N are used to investigate meridional heat transport variability in the section and its impact on transatlantic heat flux. Estimates of heat ...

Eve R. Fillenbaum; Thomas N. Lee; William E. Johns; Rainer J. Zantopp

1997-01-01T23:59:59.000Z

444

Development of a fuel-rod simulator and small-diameter thermocouples for high-temperature, high-heat-flux tests in the Gas-Cooled Fast Reactor Core Flow Test Loop  

SciTech Connect

The Core Flow Test Loop was constructed to perform many of the safety, core design, and mechanical interaction tests in support of the Gas-Cooled Fast Reactor (GCFR) using electrically heated fuel rod simulators (FRSs). Operation includes many off-normal or postulated accident sequences including transient, high-power, and high-temperature operation. The FRS was developed to survive: (1) hundreds of hours of operation at 200 W/cm/sup 2/, 1000/sup 0/C cladding temperature, and (2) 40 h at 40 W/cm/sup 2/, 1200/sup 0/C cladding temperature. Six 0.5-mm type K sheathed thermocouples were placed inside the FRS cladding to measure steady-state and transient temperatures through clad melting at 1370/sup 0/C.

McCulloch, R.W.; MacPherson, R.E.

1983-03-01T23:59:59.000Z

445

Radiant Heating  

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

Radiant heating systems involve supplying heat directly to the floor or to panels in the walls or ceiling of a house. The systems depend largely on radiant heat transfer: the delivery of heat...

446

The Radiative Heating in Underexplored Bands Campaigns  

Science Conference Proceedings (OSTI)

Accurately accounting for radiative energy balance between the incoming solar and the outgoing infrared radiative fluxes is very important in modeling the Earth's climate. Water vapor absorption plays a critical role in the radiative heating rate ...

D. D. Turner; E. J. Mlawer

2010-07-01T23:59:59.000Z

447

Pool boiling heat transfer characteristics of nanofluids  

E-Print Network (OSTI)

Nanofluids are engineered colloidal suspensions of nanoparticles in water, and exhibit a very significant enhancement (up to 200%) of the boiling Critical Heat Flux (CHF) at modest nanoparticle concentrations (50.1% by ...

Kim, Sung Joong, Ph. D. Massachusetts Institute of Technology

2007-01-01T23:59:59.000Z

448

NEUTRON FLUX INTENSITY DETECTION  

DOE Patents (OSTI)

A method of measuring the instantaneous intensity of neutron flux in the core of a nuclear reactor is described. A target gas capable of being transmuted by neutron bombardment to a product having a resonance absorption line nt a particular microwave frequency is passed through the core of the reactor. Frequency-modulated microwave energy is passed through the target gas and the attenuation of the energy due to the formation of the transmuted product is measured. (AEC)

Russell, J.T.

1964-04-21T23:59:59.000Z

449

Urban Energy Fluxes in Built-Up Downtown Areas and Variations across the Urban Area, for Use in Dispersion Models  

Science Conference Proceedings (OSTI)

Surface energy fluxes, at averaging times from 10 min to 1 h, are needed as inputs to most state-of-the-art dispersion models. The sensible heat flux is a major priority, because it is combined with the momentum flux to estimate the stability, the ...

Steven Hanna; Edson Marciotto; Rex Britter

2011-06-01T23:59:59.000Z

450

Urban Energy Fluxes in Built-Up Downtown Areas and Variations across the Urban Area, for Use in Dispersion Models  

E-Print Network (OSTI)

Surface energy fluxes, at averaging times from 10 min to 1 h, are needed as inputs to most state-of-the-art dispersion models. The sensible heat flux is a major priority, because it is combined with the momentum flux to ...

Hanna, Steven

451

Heat Exchanger Fouling- Prediction, Measurement and Mitigation  

E-Print Network (OSTI)

The U. S. Department of Energy (DOE), Office of Industrial Programs (OIP) sponsors the development of innovative heat exchange systems. Fouling is a major and persistent cost associated with most industrial heat exchangers and nationally wastes an estimated 2.9 Quads per year. To predict and control fouling, three OIP projects are currently exploring heat exchanger fouling in specific industrial applications. A fouling probe has been developed to determine empirically the fouling potential of an industrial gas stream and to derive the fouling thermal resistance. The probe is a hollow metal cylinder capable of measuring the average heat flux along the length of the tube. The local heat flux is also measured by a heat flux meter embedded in the probe wall. The fouling probe has been successfully tested in the laboratory at flue gas temperatures up to 2200°F and a local heat flux up to 41,000 BTU/hr-ft2. The probe has been field tested at a coal-fired boiler plant. Future tests at a municipal waste incinerator are planned. Two other projects study enhanced heat exchanger tubes, specifically the effect of enhanced surface geometries on tube bundle performance. Both projects include fouling in a liquid heat transfer fluid. Identifying and quantifying the factors affecting fouling in these enhanced heat transfer tubes will lead to techniques to mitigate fouling.

Peterson, G. R.

1989-09-01T23:59:59.000Z

452

The Effect of Inaccuracies in Weather-Ship Data on Bulk-Derived Estimates of Flux, Stability and Sea-Surface Roughness  

Science Conference Proceedings (OSTI)

An analytical error analysis (or sensitivity study) is performed for the momentum, heat, and humidity flux estimates made from weather-ship observations by using the bulk flux method. Bulk-derived stability and roughness errors are also examined. ...

Theodore V. Blanc

1986-03-01T23:59:59.000Z

453

Numerical analysis of vapor flow in a micro heat pipe  

E-Print Network (OSTI)

The vapor flow in a flat plate micro heat pipe with both uniform and linear heat flux boundary conditions has been numerically analyzed. For both types of boundary conditions, the Navier-Stokes equations with steady incompressible two-dimensional flow were solved using the SIMPLE method. The results indicate that the pressure, shear stress, and friction factor under linear heat flux boundary conditions are considerably smoother, and hence, more closely approximate the real situation. As the heat flux increases, the pressure drop increases, but the friction factor demonstrates only a slight change for different heat flux conditions. The size and shape of the micro heat pipe vapor space was shown to have a significant influence on the vapor flow behavior for micro heat pipes. When the vapor space area decreases, the pressure drop, shear stress, and friction factor all significantly increase.

Liu, Xiaoqin

1996-01-01T23:59:59.000Z

454

NOVEMBER 1997 2847L O F G R E N Simulated Effects of Idealized Laurentian Great Lakes on  

E-Print Network (OSTI)

, in the form of four rectangular bodies of water, each occupying a single grid cell of the GCM at R30 cycle of latent and sensible heat flux. Very high upward sensible heat flux occurs over these idealized

455

Posters Comparison Between General Circulation Model Simulation...  

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

triangulation interpolation. For the GCM simulation, the monthly mean surface latent heat flux is sampled at the grid points closest to the buoy sites, then interpolated the...

456

Electroslag remelting with used fluxes  

Science Conference Proceedings (OSTI)

The Ukranian Scientific-Research Institute of Specialty Steel collaborated with plants engaged in the production of quality metals to introduce a low-waste electroslag remelting (ESR) technology employing used fluxes. It was established that the fluoride (type ANF-1) and fluoride-oxide (type ANF-6) fluxes which are widely used in ESR still have a high content of calcium fluoride and alumina and a low impurity content after 8-10 h of ESR. In the ESR of steels with used fluxes, the content of monitored components in the final slags changes negligibly, while the content of most impurities decreases. The used flux is also characterized by a low concentration of phosphorus and sulfur. It was found that flux can be used 3-5 times when it makes up 50% of the flux mixture in the charge. The savings realized from the use of spent flux in ESR amounts to 4-9 rubles/ton steel.

Yakovlev, N.F.; Sokha, Yu.S.; Oleinik, Yu.S.; Prokhorov, A.N.; Ol'shanskaya, T.V.

1988-05-01T23:59:59.000Z

457

Use of the Dryer Off-gas Latent Heat for Improved Energy Efficiency ...  

Science Conference Proceedings (OSTI)

... resulting in further reduction in energy consumption by additional 20-30 %. Energy efficiency and technology of this new innovation is discussed in the paper

458

Characteristics of Precipitation, Cloud, and Latent Heating Associated with the Madden–Julian Oscillation  

Science Conference Proceedings (OSTI)

This study investigates the evolution of cloud and rainfall structures associated with Madden–Julian oscillation (MJO) using Tropical Rainfall Measuring Mission (TRMM) data. Two complementary indices are used to define MJO phases. Joint ...

K-M. Lau; H-T. Wu

2010-02-01T23:59:59.000Z

459

The Role of Latent Heat Release in Explosive Cyclogenesis: Three Examples Based on ECMWF Operational Forecasts  

Science Conference Proceedings (OSTI)

Operational forecasts from the European Centre for Medium Range Weather Forecasts of three cases of explosive cyclogenesis of large magnitude that occurred in the North Atlantic during a 1-week period in January 1986 are presented, and results of ...

Richard J. Reed; Mark D. Albright; Adrian J. Sammons; Per Undén

1988-09-01T23:59:59.000Z

460

The Latent Heat of Single Flavor Color Superconductivity in a Magnetic Field  

E-Print Network (OSTI)

We calculate the energy release associated with first-order phase transition between different types of single flavor color superconductivity in a magnetic field.

Ping-ping Wu; Hang He; Defu Hou; Hai-cang Ren

2011-04-09T23:59:59.000Z

Note: This page contains sample records for the topic "flux latent heat" 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

Design and Analysis of a Solar Assisted Absorption Cooling System Integrated with Latent Heat Storage.  

E-Print Network (OSTI)

??Air conditioning is one of the major consumers of electrical energy in many parts of the world. The demand can be expected to increase because… (more)

Hosseini, L.

2011-01-01T23:59:59.000Z

462

High flux reactor  

DOE Patents (OSTI)

A high flux reactor is comprised of a core which is divided into two symetric segments housed in a pressure vessel. The core segments include at least one radial fuel plate. The spacing between the plates functions as a coolant flow channel. The core segments are spaced axially apart such that a coolant mixing plenum is formed between them. A channel is provided such that a portion of the coolant bypasses the first core section and goes directly into the mixing plenum. The outlet coolant from the first core segment is mixed with the bypass coolant resulting in a lower inlet temperature to the lower core segment.

Lake, James A. (Idaho Falls, ID); Heath, Russell L. (Idaho Falls, ID); Liebenthal, John L. (Idaho Falls, ID); DeBoisblanc, Deslonde R. (Summit, NJ); Leyse, Carl F. (Idaho Falls, ID); Parsons, Kent (Idaho Falls, ID); Ryskamp, John M. (Idaho Falls, ID); Wadkins, Robert P. (Idaho Falls, ID); Harker, Yale D. (Idaho Falls, ID); Fillmore, Gary N. (Idaho Falls, ID); Oh, Chang H. (Idaho Falls, ID)

1988-01-01T23:59:59.000Z

463

Changes in Vegetation Condition and Surface Fluxes during NAME 2004  

Science Conference Proceedings (OSTI)

The vegetation in the core region of the North American monsoon (NAM) system changes dramatically after the onset of the summer rains so that large changes may be expected in the surface fluxes of radiation, heat, and moisture. Most of this ...

Christopher J. Watts; Russell L. Scott; Jaime Garatuza-Payan; Julio C. Rodriguez; John H. Prueger; William P. Kustas; Michael Douglas

2007-05-01T23:59:59.000Z

464

Measuring important parameters for air-sea heat exchange Christoph S. Garbeab, Uwe Schimpfab and Bernd Jhneab  

E-Print Network (OSTI)

Measuring important parameters for air-sea heat exchange Christoph S. Garbeab, Uwe Schimpfab Exchange, Heat flux, Digital Image Processing, Surface Renewal 1. INTRODUCTION Thermographic techniques-water heat exchange. A driving force in air sea interactions is the net sea surface heat flux. It is a vital

Garbe, Christoph S.

465

The Boundary Layer of Mars: Fluxes, Stability, Turbulent Spectra, and Growth of the Mixed Layer  

Science Conference Proceedings (OSTI)

Spectra of wind from high-frequency measurements in the Martian atmospheric surface layer, along with the diurnal variation of the height of the mixed surface layer, are calculated for the first time for Mars. Heat and momentum fluxes, stability, ...

James E. Tillman; Lars Landberg; Søren E. Larsen

1994-06-01T23:59:59.000Z

466

Sensitivity of Perturbation Variance and Fluxes in Turbulent Jets to Changes in the Mean Jet  

Science Conference Proceedings (OSTI)

Synoptic-scale eddy variance and fluxes of heat and momentum in midlatitude jets are sensitive to small changes in mean jet velocity, dissipation, and static stability. In this work the change in the jet producing the greatest increase in ...

Brian F. Farrell; Petros J. Ioannou

2004-11-01T23:59:59.000Z

467

A Surface Flux Parameterization Based on the Vertically Averaged Turbulence Kinetic Energy  

Science Conference Proceedings (OSTI)

A new bulk transfer formulation for the surface turbulent fluxes of momentum, heat, and moisture has been developed by using the square root of the vertically averaged turbulent kinetic energy (TKE) in the atmospheric boundary layer as a velocity ...

Changan Zhang; David A. Randall; Chin-Hoh Moeng; Mark Branson; Kerry A. Moyer; Qing Wang

1996-11-01T23:59:59.000Z

468

Surface-Layer Fluxes Measured Using the CT2-Profile Method  

Science Conference Proceedings (OSTI)

The first experimental test of obtaining heat and momentum fluxes from measurements of the profile of the temperature structure parameter CT2 is performed. The parameter CT2 is obtained from resistance-wire thermometers as well as from optical-...

Reginald J. Hill; Gerard R. Ochs; James J. Wilson

1992-10-01T23:59:59.000Z

469

A Simple Scheme for Daytime Estimates of the Surface Fluxes from Routine Weather Data  

Science Conference Proceedings (OSTI)

In this paper a simple empirical scheme is presented, which gives hourly estimates of the surface fluxes of heat and momentum from routine weather data during daytime. The scheme is designed for grass surfaces, but it contains parameters which ...

A. A. M. Holtslag; A. P. Van Ulden

1983-04-01T23:59:59.000Z

470

Intraurban Differences of Surface Energy Fluxes in a Central European City  

Science Conference Proceedings (OSTI)

Surface properties, such as roughness and vegetation, which vary both within and between urban areas, play a dominant role in determining surface–atmosphere energy exchanges. The turbulent heat flux partitioning is examined within a single urban ...

B. Offerle; C. S. B. Grimmond; K. Fortuniak; W. Pawlak

2006-01-01T23:59:59.000Z

471

Effects of Airflow Trajectories Around Aircraft on Measurements of Scalar Fluxes  

Science Conference Proceedings (OSTI)

Potential-flow calculations of the airflow around two research aircraft are used to estimate the effect of flow distortion on measured fluxes of sensible heat and water vapor. From the calculated flow patterns, flow-distortion coefficients are ...

William A. Cooper; Diana Rogers

1991-02-01T23:59:59.000Z

472

Modification of Surface Fluxes from Component Models in Global Coupled Models  

Science Conference Proceedings (OSTI)

The present generation of global coupled ocean–atmosphere GCMs contains considerable systematic errors both in terms of net surface heat flux and simulated SSTs. Here, a global coupled GCM is used to illustrate how systematic errors in the ...

Gerald A. Meehl

1997-11-01T23:59:59.000Z

473

Accurate Radiometric Measurement of the Atmospheric Longwave Flux at theSea Surface  

Science Conference Proceedings (OSTI)

The errors in pyrgeometer measurements of the atmospheric longwave flux at the sea surface due to differential heating of the sensor dome relative to the body and to shortwave leakage through the dome are evaluated. Contrary to the findings of ...

Robin W. Pascal; Simon A. Josey

2000-09-01T23:59:59.000Z

474

Use of the Inertial Dissipation Method for Calculating Turbulent Fluxes from Low-Level Airborne Measurements  

Science Conference Proceedings (OSTI)

Airborne measurements are currently used for computing turbulence fluxes of heat and momentum. The method generally used is the eddy correlation technique, which requires sophisticated equipments to calculate the absolute velocities of the air. ...

Pierre Durand; Leonardo De Sa; Aimé Druilhet; Frédérique Said

1991-02-01T23:59:59.000Z

475

Surface Ocean Fluxes and Water-Mass Transformation Rates in the Coupled NCAR Climate System Model  

Science Conference Proceedings (OSTI)

The global distributions of the air–sea fluxes of heat and freshwater and water mass transformation rates from a control integration of the coupled National Center for Atmospheric Research (NCAR) Climate System Model (CSM) are compared with ...

Scott C. Doney; William G. Large; Frank O. Bryan

1998-06-01T23:59:59.000Z

476

The Quest for K?—Preliminary Results from Direct Measurements of Turbulent Fluxes in the Ocean  

Science Conference Proceedings (OSTI)

Simultaneous measurements of vertical velocity fluctuations, w?, and temperature fluctuations, T?, on scales of three-dimensional turbulence yield a direct measure of the turbulent heat flux, Jq. The scales contributing most significantly to Jq ...

J. N. Moum

1990-12-01T23:59:59.000Z

477

The Direct Estimation of Near-Bottom Turbulent Fluxes in the Presence of Energetic Wave Motions  

Science Conference Proceedings (OSTI)

Velocities produced by energetic waves can contaminate direct covariance estimates of near-bottom turbulent shear stress and turbulent heat flux. A new adaptive filtering technique is introduced to minimize the contribution of wave-induced ...

W. J. Shaw; J. H. Trowbridge

2001-09-01T23:59:59.000Z

478

Spatial Heterogeneity of Air–Sea Energy Fluxes over a Coral Reef—Heron Reef, Australia  

Science Conference Proceedings (OSTI)

The thermal environment of a coral reef is moderated by complex interactions of air–sea heat and moisture fluxes, local to synoptic-scale weather and reef hydrodynamics. Measurements of air–sea energy fluxes over coral reefs are essential to ...

Mellissa C. MacKellar; Hamish A. McGowan; Stuart R. Phinn

2012-07-01T23:59:59.000Z

479

Climate from borehole data: Energy fluxes and temperatures since Hugo Beltrami  

E-Print Network (OSTI)

anomaly. The vertical profile of the temperature anomaly, depends on the history of energy balance. Wang, and R. L. Bras, Energy balance at the Earth's surface: Heat flux history in eastern CanadaClimate from borehole data: Energy fluxes and temperatures since 1500 Hugo Beltrami Environmental

Beltrami, Hugo

480

Mixed Layer Lateral Eddy Fluxes Mediated by Air–Sea Interaction  

Science Conference Proceedings (OSTI)

The modulation of air–sea heat fluxes by geostrophic eddies due to the stirring of temperature at the sea surface is discussed and quantified. It is argued that the damping of eddy temperature variance by such air–sea fluxes enhances the ...

Emily Shuckburgh; Guillaume Maze; David Ferreira; John Marshall; Helen Jones; Chris Hill

2011-01-01T23:59:59.000Z

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


481

Estimates of Area-Averaged Diapycnal Fluxes from Basin-Scale Budgets  

Science Conference Proceedings (OSTI)

Estimates of area-averaged diapycnal fluxes for the southern oceans are derived from basin-scale budgets of mass, heat, and salt using a box inverse model. The diapycnal fluxes are found to be significant terms in the isopycnal budgets of mass, ...

Bernadette M. Sloyan; Stephen R. Rintoul

2000-09-01T23:59:59.000Z

482

Heating Alloys  

Science Conference Proceedings (OSTI)

...are used in many varied applications--from small household appliances to large industrial process heating systems and furnaces. In appliances or industrial process heating, the heating elements are usually either open

483

Traveling-wave device with mass flux suppression  

DOE Patents (OSTI)

A traveling-wave device is provided with the conventional moving pistons eliminated. Acoustic energy circulates in a direction through a fluid within a torus. A side branch may be connected to the torus for transferring acoustic energy into or out of the torus. A regenerator is located in the torus with a first heat exchanger located on a first side of the regenerator downstream of the regenerator relative to the direction of the circulating acoustic energy; and a second heat exchanger located on an upstream side of the regenerator. The improvement is a mass flux suppressor located in the torus to minimize time-averaged mass flux of the fluid. In one embodiment, the device further includes a thermal buffer column in the torus to thermally isolate the heat exchanger that is at the operating temperature of the device.

Swift, Gregory W. (Santa Fe, NM); Backhaus, Scott N. (Los Alamos, NM); Gardner, David L. (White Rock, NM)

2000-01-01T23:59:59.000Z

484

Six-Week Time Series Of Eddy Covariance Co2 Flux At Mammoth Mountain,  

Open Energy Info (EERE)

Six-Week Time Series Of Eddy Covariance Co2 Flux At Mammoth Mountain, Six-Week Time Series Of Eddy Covariance Co2 Flux At Mammoth Mountain, California- Performance Evaluation And Role Of Meteorological Forcing Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Six-Week Time Series Of Eddy Covariance Co2 Flux At Mammoth Mountain, California- Performance Evaluation And Role Of Meteorological Forcing Details Activities (1) Areas (1) Regions (0) Abstract: CO2 and heat fluxes were measured over a six-week period (09/08/2006 to 10/24/2006) by the eddy covariance (EC) technique at the Horseshoe Lake tree kill (HLTK), Mammoth Mountain, CA, a site with complex terrain and high, spatially heterogeneous CO2 emission rates. EC CO2 fluxes ranged from 218 to 3500 g m- 2 d- 1 (mean = 1346 g m- 2 d- 1). Using footprint modeling, EC CO2 fluxes were compared to CO2 fluxes measured by

485

Heating Systems  

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

A variety of heating technologies are available today. In addition to heat pumps, which are discussed separately, many homes and buildings use the following approaches:

486

IntroductiontoProcessEngineering(PTG) 5. Heat transfer  

E-Print Network (OSTI)

/x, T/y, T/z), Fourier's Law gives (for constant ) for the heat flux Q" = - T · The temperature field (T)dT )/(x2-x1) · For example, with (T)=0·(1+T), the heat flux Q" for T=T0 @ x=0 and T=T1 @ x be interpreted as a general physical law of the type: flow , heat, current = driving force / resistance; current

Zevenhoven, Ron

487

Modulation of near-field heat transfer between two gratings  

E-Print Network (OSTI)

We present a theoretical study of near-field heat transfer between two uniaxial anisotropic planar structures. We investigate how the distance and relative orientation (with respect to their optical axes) between the objects affect the heat flux. In particular, we show that by changing the angle between the optical axes it is possible in certain cases to modulate the net heat flux up to 90% at room temperature, and discuss possible applications of such a strong effect.

Svend-Age Biehs; Felipe S. S. Rosa; Philippe Ben-Abdallah

2011-05-18T23:59:59.000Z

488

ARM - Measurement - CO2 flux  

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

: CO2 flux The rate of flow for carbon dioxide, a heavy, colorless greenhouse gas. Categories Atmospheric Carbon, Surface Properties Instruments The above measurement is...

489

Physics of String Flux Compactifications  

E-Print Network (OSTI)

We provide a qualitative review of flux compactifications of string theory, focusing on broad physical implications and statistical methods of analysis.

Frederik Denef; Michael R. Douglas; Shamit Kachru

2007-01-06T23:59:59.000Z

490

Historical analysis of legal opinions with a sparse mixed-effects latent variable model  

Science Conference Proceedings (OSTI)

We propose a latent variable model to enhance historical analysis of large corpora. This work extends prior work in topic modelling by incorporating metadata, and the interactions between the components in metadata, in a general way. To test this, we ...

William Yang Wang; Elijah Mayfield; Suresh Naidu; Jeremiah Dittmar

2012-07-01T23:59:59.000Z

491

Solar proton fluxes since 1956  

SciTech Connect

The fluxes of protons emitted during solar flares since 1956 were evaluated. The depth-versus-activity profiles of /sup 56/Co in several lunar rocks are consistent with the solar-proton fluxes detected by experiments on several satellites. Only about 20% of the solar-proton-induced activities of /sup 22/Na and /sup 55/Fe in lunar rocks from early Apollo missions were produced by protons emitted from the sun during solar cycle 20 (1965--1975). The depth-versus-activity data for these radionuclides in several lunar rocks were used to determine the fluxes of protons during solar cycle 19 (1954--1964). The average proton fluxes for cycle 19 are about five times those for both the last million years and for cycle 20. These solar-proton flux variations correlate with changes in sunspot activity.

Reedy, R.C.

1977-04-13T23:59:59.000Z

492

Vibration Induced Droplet Generation from a Liquid Layer for Evaporative Cooling in a Heat Transfer Cell .  

E-Print Network (OSTI)

??During this investigation, vibration induced droplet generation from a liquid layer was examined as a means for achieving high heat flux evaporative cooling. Experiments were… (more)

Pyrtle, Frank, III

2005-01-01T23:59:59.000Z

493

Heat Transfer and Pressure Drop During Condensation of Refrigerants in Microchannels .  

E-Print Network (OSTI)

??Two-phase flow, boiling, and condensation in microchannels have received considerable attention in the recent past due to the growing interest in the high heat fluxes… (more)

Agarwal, Akhil

2006-01-01T23:59:59.000Z

494

Eddy Heat Fluxes and Stability of Planetary Waves. Part I  

Science Conference Proceedings (OSTI)

The stability of baroclinic Rossby waves in a zonal shear flow is examined. The model used is a linear, quasi-geostrophic, two-level, adiabatic and frictionless midlatitude ?-plane model. The perturbations consist of truncated zonal Fourier ...

Charles A. Lin

1980-11-01T23:59:59.000Z

495

Vertical Heat-Flux Measurements from a Neutrally Buoyant Float  

Science Conference Proceedings (OSTI)

A neutrally buoyant float instrumented to measure 1–5 m shear and stratification was deployed for ten days in a near-inertial critical layer at the base of a warm-core ring. Vertical velocity and temperature data, from which large-scale (>5 m) ...

Haili Sun; Eric Kunze; A. J. Williams III

1996-06-01T23:59:59.000Z

496

Heat Flux Partitioning in Open-Ocean Convection  

Science Conference Proceedings (OSTI)

Cold air blowing out over a warm ocean leads to convection over an isolated region of the ocean basin. This phenomenon, known as open-ocean convection, is often simulated by convective forcing from a circular disk much smaller than the dimension ...

David Brickman

1995-11-01T23:59:59.000Z

497

Meridional Eddy Heat Flux in the Kuroshio Extension Current  

Science Conference Proceedings (OSTI)

A set of 19 zonal vertical sections of temperature were collected in 1975 with XBT observations at 80 km spacing, made from ships-of-opportunity transiting the mid-latitude North Pacific. In the region of the Kuroshio Extension Current, around 35°...

R. L. Bernstein; W. B. White

1982-02-01T23:59:59.000Z

498

Circulation and Heat Flux in the Bermuda Triangle  

Science Conference Proceedings (OSTI)

Data from the Atlantis 215 cruise from Cape Henry to Bermuda to Fort Pierce is analyzed to determine absolute geostrophic velocities in the region. The search procedure that Fiadeiro and Veronis (1982) proposed for finding an empirical level of ...

M. E. Fiadeiro; George Veronis

1983-07-01T23:59:59.000Z

499

Study of Heat Flux in CSP Continuous Casting Mold  

Science Conference Proceedings (OSTI)

Copper-Based Multi-Component Alloys by Vacuum Distillation to Separate Copper Enriched Lead, Silver and Other Valuable Metals Research · Cost Benefits of ...

500

The Role of Windward-Side Diabatic Heating in Sierra Nevada Spillover Precipitation  

Science Conference Proceedings (OSTI)

This study focuses on the meso-?- and meso-?-scale manifestations of the latent-heat-induced reduction of windward-side blocking to two flood-producing precipitation events on the leeside of the Sierra Nevada. Two simulations were performed—one ...

Michael L. Kaplan; Ramesh K. Vellore; Phillip J. Marzette; John M. Lewis

2012-08-01T23:59:59.000Z