Sample records for latent heat flux

  1. Global patterns of landatmosphere fluxes of carbon dioxide, latent heat, and sensible heat derived from eddy covariance,

    E-Print Network [OSTI]

    Chen, Jiquan

    (NEE), latent energy (LE), and sensible heat (H) based on remote sensing indices, climateGlobal patterns of landatmosphere fluxes of carbon dioxide, latent heat, and sensible heat derived

  2. A. Gershunov R. Roca Coupling of latent heat flux and the greenhouse effect by large-scale

    E-Print Network [OSTI]

    A. Gershunov Æ R. Roca Coupling of latent heat flux and the greenhouse effect by large Abstract Coupled variability of the greenhouse effect (GH) and latent heat flux (LHF) over the tropical of convection) form regions of strong greenhouse effect in tropical convergence zones while subtropical high

  3. MARINE STRATUS CLOUD LIFECYCLE MODULATED BY LATENT HEAT FLUX IN A COASTAL OCEAN UPWELLING REGION

    E-Print Network [OSTI]

    MARINE STRATUS CLOUD LIFECYCLE MODULATED BY LATENT HEAT FLUX IN A COASTAL OCEAN UPWELLING REGION, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark

  4. Simulated and observed fluxes of sensible and latent heat and CO2 at the WLEF-TV tower using SiB2.5

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    Simulated and observed fluxes of sensible and latent heat and CO2 at the WLEF-TV tower using SiB2, Boulder, CO, USA Abstract Three years of meteorological data collected at the WLEF-TV tower were used the WLEF tower, which were not present in the SiB simulation. The model overestimated the magnitude

  5. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    designs (relatively) Photovoltaic Solar P a n e l AtmosphereCALIFORNIA, SAN DIEGO Photovoltaic Roof Heat Flux A ThesisABSTRACT OF T H E THESIS Photovoltaic Roof Heat Flux by

  6. ARM - Measurement - Latent heat flux

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow,ice particleSizegovMeasurementsIsotope

  7. Heat-transfer coefficients in agitated vessels. Latent heat models

    SciTech Connect (OSTI)

    Kumpinsky, E. [Ashland Chemical Co., Columbus, OH (United States)] [Ashland Chemical Co., Columbus, OH (United States)

    1996-03-01T23:59:59.000Z

    Latent heat models were developed to calculate heat-transfer coefficients in agitated vessels for two cases: (1) heating with a condensable fluid flowing through coils and jackets; (2) vacuum reflux cooling with an overhead condenser. In either case the mathematical treatment, based on macroscopic balances, requires no iterative schemes. In addition to providing heat-transfer coefficients, the models predict flow rates of service fluid through the coils and jackets, estimate the percentage of heat transfer due to latent heat, and compute reflux rates.

  8. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    e l Atmosphere ceiling, back panel roof, exposed roof insideSAN DIEGO Photovoltaic Roof Heat Flux A Thesis submitted i no n Convection Exposed Roof Temperature Seasonal Temperature

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

    E-Print Network [OSTI]

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

    2006-01-01T23:59:59.000Z

    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...

  10. Optical heat flux gauge

    DOE Patents [OSTI]

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

    1991-04-09T23:59:59.000Z

    A heat flux gauge is disclosed comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator, wherein each thermographic layer comprises a plurality of respective thermographic sensors in a juxtaposed relationship with respect to each other. 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 figures.

  11. Physical model for the latent heat of fusion

    E-Print Network [OSTI]

    Jozsef Garai

    2004-11-06T23:59:59.000Z

    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.

  12. High Heat Flux Components Program

    SciTech Connect (OSTI)

    Whitley, J.B.

    1983-01-01T23:59:59.000Z

    Purpose is the development of the technologies necessary to design, build and operate high heat flux components such as actively cooled limiters, divertor collector plates, R.F. antennas, mirror end cells, mirror halo collectors, direct convertor collectors, and neutral beam dumps. These components require an integrated design that considers the plasma-materials interaction (PMI) issues, heat removal problems and materials issues (including possible low Z coatings and claddings). As a general definition, high heat flux components see heat fluxes ranging from 1 to 100 MW/m/sup 2/. Suitable materials include copper and copper alloys.

  13. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    transient the heat transfer model. T h i s required the roofto develop and calibrate heat transfer models to be able toE S station, the heat transfer models described i n sections

  14. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    under the offset unit's solar panel, the hf formula (16) wasdrop below the angle unit's solar panel at night time. D u rfor both the units, the solar panel covered roof was a heat

  15. Isentropic Slopes, Downgradient Eddy Fluxes, and the Extratropical Atmospheric Circulation Response to Tropical Tropospheric Heating

    E-Print Network [OSTI]

    to Tropical Tropospheric Heating AMY H. BUTLER NOAA/NWS/NCEP/Climate Prediction Center, Camp Springs, Maryland of the midlatitude jets and their associated eddy fluxes of heat and potential vorticity (PV). Experiments run latent heating and thus locally enhanced warming in the tropical troposphere. Here the authors provide

  16. High Heat Flux Thermoelectric Module Using Standard Bulk Material...

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

    Heat Flux Thermoelectric Module Using Standard Bulk Material High Heat Flux Thermoelectric Module Using Standard Bulk Material Presents high heat flux thermoelectric module design...

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

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

    Cook, David

    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.

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

    SciTech Connect (OSTI)

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

    2014-01-02T23:59:59.000Z

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

  19. Method for charging and discharging a latent-heat storage medium and heat storage

    SciTech Connect (OSTI)

    Kreikenbohm, R.; Reusch, H.

    1982-12-28T23:59:59.000Z

    A heat storage unit is disclosed having a vertically cylindrical container accommodating a latent-heat storage medium and a conduit introducing a heat carrier liquid not miscible with the medium at the bottom of the container. The conduit has an exit nozzle which is located outside the axial center of the cylinder and nearly perpendicular to the radius of the cylinder so that the heat carrier liquid enters the cylinder at the bottom in a direction to cause the heat storage melt to be set into a rotary motion.

  20. Method for charging and discharging a latent-heat storage medium and heat storage

    SciTech Connect (OSTI)

    Kreikenbohm, R.; Reusch, H.

    1981-10-13T23:59:59.000Z

    A heat storage unit is disclosed having a vertically cylindrical container accommodating a latent-heat storage medium and a conduit introducing a heat carrier liquid not miscible with the medium at the bottom of the container. The conduit has an exit nozzle which is located outside the axial center of the cylinder and nearly perpendicular to the radius of the cylinder so that the heat carrier liquid enters the cylinder at the bottom in a direction to cause the heat storage melt to be set into a rotary motion.

  1. An investigation into the thermal properties of selected sensible and latent heat storage materials 

    E-Print Network [OSTI]

    Wood, Stanley Clayton

    1982-01-01T23:59:59.000Z

    in the latent heat of fusion. Considerable work has been done in analyzing latent heat storage systems. Telkes and Raymond [lj did early work with a sodium sulfate system using sealed drums. iVore recent experimental work was conducted with other salt...

  2. An investigation into the thermal properties of selected sensible and latent heat storage materials

    E-Print Network [OSTI]

    Wood, Stanley Clayton

    1982-01-01T23:59:59.000Z

    in the latent heat of fusion. Considerable work has been done in analyzing latent heat storage systems. Telkes and Raymond [lj did early work with a sodium sulfate system using sealed drums. iVore recent experimental work was conducted with other salt...

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

    SciTech Connect (OSTI)

    Blanchat, Thomas K.; Hanks, Charles R.

    2013-04-01T23:59:59.000Z

    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.

  4. A model for the latent heat of melting in free standing metal nanoparticles

    SciTech Connect (OSTI)

    Shin, Jeong-Heon; Deinert, Mark R., E-mail: mdeinert@mail.utexas.edu [Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78715 (United States)

    2014-04-28T23:59:59.000Z

    Nanoparticles of many metals are known to exhibit scale dependent latent heats of melting. Analytical models for this phenomenon have so far failed to completely capture the observed phenomena. Here we present a thermodynamic analysis for the melting of metal nanoparticles in terms of their internal energy and a scale dependent surface tension proposed by Tolman. The resulting model predicts the scale dependence of the latent heat of melting and is confirmed using published data for tin and aluminum.

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

    SciTech Connect (OSTI)

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

    2013-08-14T23:59:59.000Z

    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.

  6. Critical heat flux test apparatus

    DOE Patents [OSTI]

    Welsh, Robert E. (West Mifflin, PA); Doman, Marvin J. (McKeesport, PA); Wilson, Edward C. (West Mifflin, PA)

    1992-01-01T23:59:59.000Z

    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.

  7. Longitudinal variation of tides in the MLT region: 2. Relative effects of solar radiative and latent heating

    E-Print Network [OSTI]

    Forbes, Jeffrey

    of solar radiative and latent heating Xiaoli Zhang,1 Jeffrey M. Forbes,1 and Maura E. Hagan2 Received 11 study examines the relative importance of radiative heating and latent heating in accounting (GSWM) and new tidal heating rates derived from International Satellite Cloud Climatology Project (ISCCP

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

    E-Print Network [OSTI]

    Todreas, Neil E.

    1965-01-01T23:59:59.000Z

    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 ...

  9. Building wall heat flux calculations

    SciTech Connect (OSTI)

    Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.

    1987-06-01T23:59:59.000Z

    Calculations of the heat transfer through the standard stud wall structure of a residential building are described. The wall cavity contains no insulation. Four of the five test cases represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using the Implicit Compressible Eulerian (ICE) algorithm. The fluid flow calculation is coupled to the radiation-conduction model for the solid portions of the system. Conduction through sill plates is about 4% of the total heat transferred through a composite wall. All of the other model elements (conduction through wall board, sheathing, and siding; convection from siding and wallboard to ambients; and radiation across the wall cavity) are required to accurately predict the heat transfer through a wall. Addition of a foil liner on one inner surface of the wall cavity reduces the total heat transferred by almost 50%.

  10. Building wall heat flux calculations

    SciTech Connect (OSTI)

    Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.

    1987-01-01T23:59:59.000Z

    Calculations of the heat transfer through the standard stud wall structure of a residential building are described. The wall cavity contains no insulation. Four of the five test cases represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using the Implicit Compressible Eulerian (ICE) algorithm. The fluid flow calculation is coupled to the radiation-conduction model for the solid portions of the system. Conduction through sill plates is about 4% of the total heat transferred through a composite wall.

  11. ARM - Measurement - Soil heat flux

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDCnarrowbandheat flux ARM Data Discovery Browse Data Comments? We

  12. Experimental investigation of the latent heat of vaporization in aqueous nanofluids

    SciTech Connect (OSTI)

    Lee, Soochan; Phelan, Patrick E., E-mail: phelan@asu.edu; Dai, Lenore; Prasher, Ravi; Gunawan, Andrey [School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287-6106 (United States); Taylor, Robert A. [School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney 2052 (Australia)

    2014-04-14T23:59:59.000Z

    This paper reports an experimental investigation of the latent heat of vaporization (h{sub fg}) in nanofluids. Two different types of nanoparticles, graphite and silver, suspended in deionized water were exposed to a continuous laser beam (130 mW, 532?nm) to generate boiling. The latent heat of vaporization in the nanofluids was determined by the measured vapor mass generation and the heat input. To ensure that the measured h{sub fg} values are independent of heating method, the experiments were repeated with an electrically heated hot wire as a primary heat input. These experiments show considerable variation in the h{sub fg} of nanofluids. That is, graphite nanofluid exhibits an increased h{sub fg} and silver nanofluid shows a decrease in h{sub fg} compared to the value for pure water. As such, these results indicate that relatively low mass fractions of nanoparticles can apparently create large changes in h{sub fg}.

  13. Latent heat fluxes through nano-engineered porous materials

    E-Print Network [OSTI]

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

    2007-01-01T23:59:59.000Z

    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 ...

  14. Contactless heat flux control with photonic devices

    E-Print Network [OSTI]

    Ben-Abdallah, Philippe

    2015-01-01T23:59:59.000Z

    The ability to control electric currents in solids using diodes and transistors is undoubtedly at the origin of the main developments in modern electronics which have revolutionized the daily life in the second half of 20th century. Surprisingly, until the year 2000 no thermal counterpart for such a control had been proposed. Since then, based on pioneering works on the control of phononic heat currents new devices were proposed which allow for the control of heat fluxes carried by photons rather than phonons or electrons. The goal of the present paper is to summarize the main advances achieved recently in the field of thermal energy control with photons.

  15. Determination of solid fractiontemperature relation and latent heat using full scale

    E-Print Network [OSTI]

    Beckermann, Christoph

    on five such corrosion resistant alloys: superaustenitic stainless steel CN3MN, duplex stainless steels CD available. The alloys selected consist of three stainless steels (super- austenitic CN3MN and duplexes CD3MN, Latent heat, Stainless steels, Nickel based alloys Introduction Casting simulation is routinely used

  16. Assessment and Prediction of the Thermal Performance of a Centralized Latent Heat Thermal Energy Storage Utilizing Artificial Neural Network

    E-Print Network [OSTI]

    El-Sawi, A.; Haghighat, F.; Akbari, H.

    2013-01-01T23:59:59.000Z

    A simulation tool is developed to analyze the thermal performance of a centralized latent heat thermal energy storage system (LHTES) using computational fluid dynamics (CFD). The LHTES system is integrated with a mechanical ventilation system...

  17. SU(3) Latent Heat and Surface Tension from Tree Level and Tadpole Improved Actions

    E-Print Network [OSTI]

    B. Beinlich; F. Karsch; A. Peikert

    1996-08-27T23:59:59.000Z

    We analyze the latent heat and surface tension at the SU(3) deconfinement phase transition with tree level and tadpole improved Symanzik actions on lattices with temporal extent $N_\\tau = 3$ and 4 and spatial extent $N_\\sigma/ N_\\tau = 4$, 6 and 8. In comparison to the standard Wilson action we do find a drastic reduction of cut-off effects already with tree level improved actions. On lattices with temporal extent $N_\\tau=4$ results for the surface tension and latent heat obtained with a tree level improved action agree well with those obtained with a tadpole improved action. A comparison with $N_\\tau=3$ calculations, however, shows that results obtained with tadpole action remain unaffected by cut-off effects even on this coarse lattice, while the tree level action becomes sensitive to the cut-off. For the surface tension and latent heat we find $\\sigma_I/ T_c^3 = 0.0155~(16)$ and $\\Delta\\epsilon/T_c^4 = 1.40~(9)$, respectively.

  18. SU(3) Latent Heat and Surface Tension from Tree Level and Tadpole Improved Actions

    E-Print Network [OSTI]

    Beinlich, B; Peikert, A

    1996-01-01T23:59:59.000Z

    We analyze the latent heat and surface tension at the SU(3) deconfinement phase transition with tree level and tadpole improved Symanzik actions on lattices with temporal extent $N_\\tau = 3$ and 4 and spatial extent $N_\\sigma/ N_\\tau = 4$, 6 and 8. In comparison to the standard Wilson action we do find a drastic reduction of cut-off effects already with tree level improved actions. On lattices with temporal extent $N_\\tau=4$ results for the surface tension and latent heat obtained with a tree level improved action agree well with those obtained with a tadpole improved action. A comparison with $N_\\tau=3$ calculations, however, shows that results obtained with tadpole action remain unaffected by cut-off effects even on this coarse lattice, while the tree level action becomes sensitive to the cut-off. For the surface tension and latent heat we find $\\sigma_I/ T_c^3 = 0.0155~(16)$ and $\\Delta\\epsilon/T_c^4 = 1.40~(9)$, respectively.

  19. Direct numerical simulation of turbulent heat transfer in annuli: effect of heat flux ratio.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Direct numerical simulation of turbulent heat transfer in annuli: effect of heat flux ratio. M-la-Vall´ee cedex 2, France (Dated: October 23, 2008) Abstract Fully developed turbulent flow and heat transfer square (rms) of temperature fluctuations, turbulent heat fluxes, heat transfer, ...). To validate

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

    E-Print Network [OSTI]

    Renzi, Kimberly Irene

    1998-01-01T23:59:59.000Z

    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 were conducted utilizing four copper heat pipes, lined with copper mesh...

  1. NIST Measurement Services: Heat-Flux Sensor Calibration

    E-Print Network [OSTI]

    NIST Measurement Services: Heat-Flux Sensor Calibration NIST Special Publication 250-65 Benjamin K Special Publication 250-65 NIST MEASUREMENT SERVICES: Heat-Flux Sensor Calibration Benjamin K. Tsai GAITHERSBURG, MD: 2004 #12;iii PREFACE The calibration and related measurement services of the National

  2. Tracking heat flux sensors for concentrating solar applications

    DOE Patents [OSTI]

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

    2013-06-11T23:59:59.000Z

    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.

  3. High flux heat transfer in a target environment

    E-Print Network [OSTI]

    McDonald, Kirk

    High flux heat transfer in a target environment T. Davenne High Power Targets Group Rutherford Valid for: Consider turbulent heat transfer in a 1.5mm diameter pipe ­ Dittus Boelter correlation Achenbach correlation for heat transfer in a packed bed of spheres Max power density for a sphere

  4. Determination of pool boiling Critical Heat Flux enhancement in nanofluids

    E-Print Network [OSTI]

    Truong, Bao H. (Bao Hoai)

    2007-01-01T23:59:59.000Z

    Nanofluids are engineered colloids composed of nano-size particles dispersed in common fluids such as water or refrigerants. Using an electrically controlled wire heater, pool boiling Critical Heat Flux (CHF) of Alumina ...

  5. Full-scale study of a building equipped with phase change material wallboards and a multi-layer rack latent heat thermal energy store system

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -layer rack latent heat thermal energy store system Julien Borderon1 , Joseph Virgone2 , Richard Cantin1 installed as wallboard and as latent heat thermal energy storage system coupled with the ventilation system for the ventilation air is efficient. INTRODUCTION Nowadays, thermal energy storage systems are one way for reducing

  6. Divertor Heat Flux Mitigation in the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    Soukhanovskii, V A; Maingi, R; Gates, D A; Menard, J E; Paul, S F; Raman, R; Roquemore, A L; Bell, M G; Bell, R E; Boedo, J A; Bush, C E; Kaita, R; Kugel, H W; LeBlanc, B P; Mueller, D

    2008-08-04T23:59:59.000Z

    Steady-state handling of divertor heat flux is a critical issue for both ITER and spherical torus-based devices with compact high power density divertors. Significant reduction of heat flux to the divertor plate has been achieved simultaneously with favorable core and pedestal confinement and stability properties in a highly-shaped lower single null configuration in the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40, 557 2000] using high magnetic flux expansion at the divertor strike point and the radiative divertor technique. A partial detachment of the outer strike point was achieved with divertor deuterium injection leading to peak flux reduction from 4-6 MW m{sup -2} to 0.5-2 MW m{sup -2} in small-ELM 0.8-1.0 MA, 4-6 MW neutral beam injection-heated H-mode discharges. A self-consistent picture of outer strike point partial detachment was evident from divertor heat flux profiles and recombination, particle flux and neutral pressure measurements. Analytic scrape-off layer parallel transport models were used for interpretation of NSTX detachment experiments. The modeling showed that the observed peak heat flux reduction and detachment are possible with high radiated power and momentum loss fractions, achievable with divertor gas injection, and nearly impossible to achieve with main electron density, divertor neutral density or recombination increases alone.

  7. Characterization of local heat fluxes around ICRF antennas on JET

    SciTech Connect (OSTI)

    Campergue, A.-L. [Ecole Nationale des Ponts et Chaussées, F77455 Marne-la-Vallée (France); Jacquet, P.; Monakhov, I.; Arnoux, G.; Brix, M.; Sirinelli, A. [Euratom/CCFE Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Bobkov, V. [Max-Planck-Institut für Plasmaphysik, EURATOM-Assoziation, Garching (Germany); Milanesio, D. [Politecnico di Torino, Department of Electronics, Torino (Italy); Colas, L. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Collaboration: JET-EFDA Contributors

    2014-02-12T23:59:59.000Z

    When using Ion Cyclotron Range of Frequency (ICRF) heating, enhanced power deposition on Plasma-Facing Components (PFCs) close to the antennas can occur. Experiments have recently been carried out on JET with the new ITER-Like-Wall (ILW) to characterize the heat fluxes on the protection of the JET ICRF antennas, using Infra-Red (IR) thermography measurement. The measured heat flux patterns along the poloidal limiters surrounding powered antennas were compared to predictions from a simple RF sheath rectification model. The RF electric field, parallel to the static magnetic field in front of the antenna, was evaluated using the TOPICA code, integrating a 3D flattened model of the JET A2 antennas. The poloidal density variation in front of the limiters was obtained from the mapping of the Li-beam or edge reflectometry measurements using the flux surface geometry provided by EFIT equilibrium reconstruction. In many cases, this simple model can well explain the position of the maximum heat flux on the different protection limiters and the heat-flux magnitude, confirming that the parallel RF electric field and the electron plasma density in front of the antenna are the main driving parameters for ICRF-induced local heat fluxes.

  8. Systematic investigation of the effects of hydrophilic porosity on boiling heat transfer and critical heat flux

    E-Print Network [OSTI]

    Tetreault-Friend, Melanie

    2014-01-01T23:59:59.000Z

    Predicting the conditions of critical heat flux (CHF) is of considerable importance for safety and economic reasons in heat transfer units, such as in nuclear power plants. It is greatly advantageous to increase this thermal ...

  9. Nano-engineering the boiling surface for optimal heat transfer rate and critical heat flux

    E-Print Network [OSTI]

    Phillips, Bren Andrew

    2011-01-01T23:59:59.000Z

    The effects on pool boiling characteristics such as critical heat flux and the heat transfer coefficient of different surface characteristics such as surface wettability, roughness, morphology, and porosity are not well ...

  10. Thermal response of a flat heat pipe sandwich structure to a localized heat flux

    E-Print Network [OSTI]

    Wadley, Haydn

    The temperature distribution across a flat heat pipe sandwich structure, subjected to an intense localized thermal metal foam wick and distilled water as the working fluid. Heat was applied via a propane torch and radiative heat transfer. A novel method was developed to estimate experimentally, the heat flux distribution

  11. Eddy heat fluxes at Drake Passage due to mesoscale motions

    E-Print Network [OSTI]

    Rojas Recabal, Ricardo Luis

    1982-01-01T23:59:59.000Z

    EDDY HEAT FLUKES AT DRAKE PASSAGE DUE TO MESOSCALE MOTIONS A Thesis by RICARDO LUIS ROJAS RECABAL Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May... 1982 Major Subject: Oceanography EDDY HEAT FLUXES AT DRAKE PASSAGE DUE TO MESOSCALE NOTIONS A Thesis by RICARDO LUIS ROJAS RECABAL Approved as to style and content by: was )W-~ Member em er May 1982 ABSTRACT Eddy Heat Fluxes at Drake Passage...

  12. QUANTIFICATION OF HEAT FLUX FROM A REACTING THERMITE SPRAY

    SciTech Connect (OSTI)

    Eric Nixon; Michelle Pantoya

    2009-07-01T23:59:59.000Z

    Characterizing the combustion behaviors of energetic materials requires diagnostic tools that are often not readily or commercially available. For example, a jet of thermite spray provides a high temperature and pressure reaction that can also be highly corrosive and promote undesirable conditions for the survivability of any sensor. Developing a diagnostic to quantify heat flux from a thermite spray is the objective of this study. Quick response sensors such as thin film heat flux sensors can not survive the harsh conditions of the spray, but more rugged sensors lack the response time for the resolution desired. A sensor that will allow for adequate response time while surviving the entire test duration was constructed. The sensor outputs interior temperatures of the probes at known locations and utilizes an inverse heat conduction code to calculate heat flux values. The details of this device are discussed and illustrated. Temperature and heat flux measurements of various thermite spray conditions are reported. Results indicate that this newly developed energetic material heat flux sensor provides quantitative data with good repeatability.

  13. Downstream Heat Flux Profile vs. Midplane T Profile in Tokamaks

    SciTech Connect (OSTI)

    Robert J. Goldston

    2009-08-20T23:59:59.000Z

    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.

  14. Remote high-temperature insulatorless heat-flux gauge

    DOE Patents [OSTI]

    Noel, B.W.

    1993-12-28T23:59:59.000Z

    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.

  15. Remote high-temperature insulatorless heat-flux gauge

    DOE Patents [OSTI]

    Noel, Bruce W. (Espanola, NM)

    1993-01-01T23:59:59.000Z

    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.

  16. Micro and nanostructured surfaces for enhanced phase change heat transfer

    E-Print Network [OSTI]

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

    2013-01-01T23:59:59.000Z

    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, ...

  17. DIRECT MEASUREMENT OF HEAT FLUX FROM COOLING LAKE THERMAL IMAGERY

    SciTech Connect (OSTI)

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

    2007-12-19T23:59:59.000Z

    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.

  18. Sea surface exchanges of momentum, heat, and freshwater determined by satellite remote sensing

    E-Print Network [OSTI]

    Yu, Lisan

    1 Sea surface exchanges of momentum, heat, and freshwater determined by satellite remote sensing Freshwater flux Latent heat flux Longwave radiation Satellite remote sensing Sea surface flux estimation Sensible heat flux Shortwave radiation Surface wind fields 2 #12;Sea surface exchanges of momentum, heat

  19. Determining heat fluxes from temperature measurements made in massive walls

    SciTech Connect (OSTI)

    Balcomb, J.D.; Hedstrom, J.C.

    1980-01-01T23:59:59.000Z

    A technique is described for determining heat fluxes at the surfaces of masonry walls or floors using temperature data measured at two points within the wall, usually near the surfaces. The process consists of solving the heat diffusion equation in one dimension using finite difference techniques given two measured temperatures as input. The method is fast and accurate and also allows for an in-situ measurement of wall thermal diffusivity if a third temperature is measured. The method is documented in sufficient detail so that it can be readily used by the reader. Examples are given for heat flow through walls. Annual results for two cases are presented. The method has also been used to determine heat flow into floors.

  20. Method of fission heat flux determination from experimental data

    DOE Patents [OSTI]

    Paxton, Frank A. (Schenectady, NY)

    1999-01-01T23:59:59.000Z

    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.

  1. PUBLISHED VERSION Characterization of local heat fluxes around ICRF antennas on JET

    E-Print Network [OSTI]

    ) to characterize the heat fluxes on the protection of the JET ICRF antennas, using Infra-Red (IR) thermography

  2. Calculation of Heating Values for the High Flux Isotope Reactor

    SciTech Connect (OSTI)

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

    2012-01-01T23:59:59.000Z

    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.

  3. Modeling epoxy foams exposed to fire-like heat fluxes.

    SciTech Connect (OSTI)

    Hobbs, Michael L.

    2004-11-01T23:59:59.000Z

    A decomposition chemistry and heat transfer model to predict the response of removable epoxy foam (REF) exposed to fire-like heat fluxes is described. The epoxy foam was created using a perfluorohexane blowing agent with a surfactant. The model includes desorption of the blowing agent and surfactant, thermal degradation of the epoxy polymer, polymer fragment transport, and vapor-liquid equilibrium. An effective thermal conductivity model describes changes in thermal conductivity with reaction extent. Pressurization is modeled assuming: (1) no strain in the condensed-phase, (2) no resistance to gas-phase transport, (3) spatially uniform stress fields, and (4) no mass loss from the system due to venting. The model has been used to predict mass loss, pressure rise, and decomposition front locations for various small-scale and large-scale experiments performed by others. The framework of the model is suitable for polymeric foams with absorbed gases.

  4. Modeling epoxy foams exposed to fire-like heat fluxes.

    SciTech Connect (OSTI)

    Hobbs, Michael L.

    2004-10-01T23:59:59.000Z

    A decomposition chemistry and heat transfer model to predict the response of removable epoxy foam (REF) exposed to fire-like heat fluxes is described. The epoxy foam was created using a perfluorohexane blowing agent with a surfactant. The model includes desorption of the blowing agent and surfactant, thermal degradation of the epoxy polymer, polymer fragment transport, and vapor-liquid equilibrium. An effective thermal conductivity model describes changes in thermal conductivity with reaction extent. Pressurization is modeled assuming: (1) no strain in the condensed-phase, (2) no resistance to gas-phase transport, (3) spatially uniform stress fields, and (4) no mass loss from the system due to venting. The model has been used to predict mass loss, pressure rise, and decomposition front locations for various small-scale and large-scale experiments performed by others. The framework of the model is suitable for polymeric foams with absorbed gases.

  5. Structural design criteria for high heat flux components.

    SciTech Connect (OSTI)

    Majumdar, S.

    1999-07-14T23:59:59.000Z

    The high temperature design rules of the ITER Structural Design Criteria (ISDC), are applied to first wall designs with high heat flux. The maximum coolant pressure and surface heat flux capabilities are shown to be determined not only by the mechanical properties of the first wall material but also by the details of the blanket design. In a high power density self-cooled lithium blanket, the maximum primary stress in the first wall is controlled by many of the geometrical parameters of the blanket, such as, first wall span, first wall curvature, first wall thickness, side wall thickness, and second wall thickness. The creep ratcheting lifetime of the first wall is also shown to be controlled by many of the same geometrical parameters as well as the coolant temperature. According to most high temperature design codes, the time-dependent primary membrane stress allowable are based on the average temperature (ignoring thermal stress). Such a procedure may sometimes be unconservative, particularly for embrittled first walls with large temperature gradients. The effect of secondary (thermal) stresses on the accumulation of creep deformation is illustrated with a vanadium alloy flat plate first wall design.

  6. Effect of combined nanoparticle and polymeric dispersions on critical heat flux, nucleate boiling heat transfer coefficient, and coating adhesion

    E-Print Network [OSTI]

    Edwards, Bronwyn K

    2009-01-01T23:59:59.000Z

    An experimental study was performed to determine thermal performance and adhesion effects of a combined nanoparticle and polymeric dispersion coating. The critical heat flux (CHF) values and nucleate boiling heat transfer ...

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

    E-Print Network [OSTI]

    Bateni, Sayed Mohyeddin

    2011-01-01T23:59:59.000Z

    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. ...

  8. Penetrative turbulence associated with mesoscale surface heat flux variations

    E-Print Network [OSTI]

    Alam, Jahrul M

    2015-01-01T23:59:59.000Z

    This article investigates penetrative turbulence in the atmospheric boundary layer. Using a large eddy simulation approach, we study characteristics of the mixed layer with respect to surface heat flux variations in the range from 231.48 W/m$^2$ to 925.92 W/m$^2$, and observe that the surface heterogeneity on a spatial scale of $20$ km leads to downscale turbulent kinetic energy cascade. Coherent fluctuations of mesoscale horizontal wind is observed at 100m above the ground. Such a surface induced temporal oscillations in the horizontal wind suggest a rapid jump in mesocale wind forecasts, which is difficult to parameterize using traditional one-dimensional ensemble-mean models. Although the present work is idealized at a typical scale (20km) of surface heterogeneity, the results help develop effective subgrid scale parameterization schemes for classical weather forecasting mesoscale models.

  9. Quantitative method for measuring heat flux emitted from a cryogenic object

    DOE Patents [OSTI]

    Duncan, R.V.

    1993-03-16T23:59:59.000Z

    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.

  10. Quantitative method for measuring heat flux emitted from a cryogenic object

    DOE Patents [OSTI]

    Duncan, Robert V. (Tijeras, NM)

    1993-01-01T23:59:59.000Z

    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.

  11. Effects of Temperature Gradients and Heat Fluxes on High-Temperature Oxidation

    SciTech Connect (OSTI)

    Holcomb, G.R.

    2008-04-01T23:59:59.000Z

    The effects of a temperature gradient and heat flux on point defect diffusion in protective oxide scales were examined. Irreversible thermodynamics were used to expand Fick’s first law of diffusion to include a heat-flux term—a Soret effect. Oxidation kinetics were developed for the oxidation of cobalt and of nickel doped with chromium. Research is described to verify the effects of a heat flux by oxidizing pure cobalt in a temperature gradient at 900 °C, and comparing the kinetics to isothermal oxidation. No evidence of a heat flux effect was found.

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz9MorganYouofSolvingexplore2 SpaceFacilities

  13. autoinmune latente del: Topics by E-print Network

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

    We describe algorithms for estimating binary latent known, understood, and used tool, multivariate nor- mal distributions, not always applicable Kirshner, Sergey 9 Latent heat...

  14. OPTIMIZATION AND DESIGN GUIDELINES FOR HIGH FLUX MICRO-CHANNEL HEAT SINKS FOR LIQUID AND GASEOUS SINGLE-PHASE FLOW

    E-Print Network [OSTI]

    Müller, Norbert

    forced convection micro-channel heat sinks for minimum pump power at high heat fluxes. Results gained orders of magnitude, especially for high heat flux devices. Using water and air as coolants, designs for heat fluxes of >10 kW/cm2 and >100 W/cm2 respectively with pump/fan power expenses less than 1

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

    E-Print Network [OSTI]

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

    2006-01-01T23:59:59.000Z

    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...

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

    E-Print Network [OSTI]

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

    2006-01-01T23:59:59.000Z

    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...

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

    E-Print Network [OSTI]

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

    2009-01-01T23:59:59.000Z

    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 ...

  18. AEROSOL-CLOUD INTERACTIONS CONTROL OF EARTH RADIATION AND LATENT HEAT RELEASE BUDGETS

    E-Print Network [OSTI]

    Daniel, Rosenfeld

    role in energizing the climate system: they reflect much of the solar radiation back to space and so and aerosols reflect back to space 22.5% of the solar radiation (Figure 1). An additional 8.8% is reflected.1% are absorbed by the surface. Surface evaporation consumes 22.8% of the solar energy that subsequently heats

  19. E × B shear pattern formation by radial propagation of heat flux waves

    SciTech Connect (OSTI)

    Kosuga, Y., E-mail: kosuga@riam.kyushu-u.ac.jp [WCI Center for Fusion Theory, NFRI, Daejeon (Korea, Republic of); IAS and RIAM, Kyushu University, Fukuoka (Japan); Diamond, P. H. [WCI Center for Fusion Theory, NFRI, Daejeon (Korea, Republic of) [WCI Center for Fusion Theory, NFRI, Daejeon (Korea, Republic of); CASS and CMTFO, University of California, San Diego, California 92093 (United States); Dif-Pradalier, G. [CEA, IRFM, Paul-lez-Durance Cedex (France)] [CEA, IRFM, Paul-lez-Durance Cedex (France); Gürcan, Ö. D. [Laboratoire de Physique des Plasmas, Ecole Polytechnique, Palaiseau (France)] [Laboratoire de Physique des Plasmas, Ecole Polytechnique, Palaiseau (France)

    2014-05-15T23:59:59.000Z

    A novel theory to describe the formation of E×B flow patterns by radially propagating heat flux waves is presented. A model for heat avalanche dynamics is extended to include a finite delay time between the instantaneous heat flux and the mean flux, based on an analogy between heat avalanche dynamics and traffic flow dynamics. The response time introduced here is an analogue of the drivers' response time in traffic dynamics. The microscopic foundation for the time delay is the time for mixing of the phase space density. The inclusion of the finite response time changes the model equation for avalanche dynamics from Burgers equation to a nonlinear telegraph equation. Based on the telegraph equation, the formation of heat flux jams is predicted. The growth rate and typical interval of jams are calculated. The connection of the jam interval to the typical step size of the E×B staircase is discussed.

  20. High Heat Flux Exposure Tests on 10mm Beryllium Tiles Brazed on Actively Cooled Vapotron made from CUCRZR

    E-Print Network [OSTI]

    High Heat Flux Exposure Tests on 10mm Beryllium Tiles Brazed on Actively Cooled Vapotron made from CUCRZR

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

    SciTech Connect (OSTI)

    Schneider, A.R.

    1980-01-01T23:59:59.000Z

    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.

  2. The effects of orientation angle, subcooling, heat flux, mass flux, and pressure on bubble growth and detachment in subcooled flow boiling

    E-Print Network [OSTI]

    Sugrue, Rosemary M

    2012-01-01T23:59:59.000Z

    The effects of orientation angle, subcooling, heat flux, mass flux, and pressure on bubble growth and detachment in subcooled flow boiling were studied using a high-speed video camera in conjunction with a two-phase flow ...

  3. Separate effects of surface roughness, wettability, and porosity on the boiling critical heat flux

    E-Print Network [OSTI]

    O'Hanley, Harry

    The separate effects of surface wettability, porosity, and roughness on the critical heat flux (CHF) of water were examined using engineered surfaces. Values explored were 0, 5, 10, and 15??m for Rz (roughness), <5°, ?75°, ...

  4. An experimental investigation of critical heat flux in subcooled internal flow

    E-Print Network [OSTI]

    Shatto, Donald Patrick

    1997-01-01T23:59:59.000Z

    diameters, tube lengths, and mass flow rates. Methods of developing predictive correlations for subcooled critical heat flux based on dimensional analysis, and the sublayer dryout model, are described and applied to the data from these experiments. When...

  5. The role of the geothermal heat flux in driving the abyssal ocean circulation

    E-Print Network [OSTI]

    Mashayek, A.

    The results presented in this paper demonstrate that the geothermal heat flux (GHF) from the solid Earth into the ocean plays a non-negligible role in determining both abyssal stratification and circulation strength. Based ...

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

    E-Print Network [OSTI]

    Truong, Bao H.

    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 ...

  7. Spatial variability in soil heat flux at three Inner Mongolia steppe ecosystems

    E-Print Network [OSTI]

    Chen, Jiquan

    Spatial variability in soil heat flux at three Inner Mongolia steppe ecosystems Changliang Shao a-covariance Grassland Inner Mongolia a b s t r a c t Closing the energy budget at flux measurement sites is problematic system within the footprints of three Eddy-covariance towers located in the steppe of Inner Mongolia

  8. Radiative Heating and the Buoyant Rise of Magnetic Flux Tubes in the Solar Interior

    E-Print Network [OSTI]

    California at Berkeley, University of

    Radiative Heating and the Buoyant Rise of Magnetic Flux Tubes in the Solar Interior Y. Fan National the e ect of radiative heating on the evolution of thin magnetic ux tubes in the solar interior Solar Observatoryy, 950 N. Cherry Ave., Tucson, AZ 85719. G. H. Fisher Space Sciences Laboratory, Univ

  9. High Heat Flux Interactions and Tritium Removal from Plasma Facing Components by a Scanning Laser'

    E-Print Network [OSTI]

    Harilal, S. S.

    its promise as an attractive, environmentally acceptable energy source[2]. Carbon based materials have-mechanical response o f graphite and carbon fiber composite (CFC) to very high heat flux includes sublimation, heating of carbon tiles. These tiles were previously used in the TFTR inner limiter and have a surface layer

  10. Identification of boundary heat fluxes in a falling film experiment using

    E-Print Network [OSTI]

    , regularization, conjugate gradient method, falling film, heat flux estimation, anisotropic finite elements, model problems must be solved. We apply a one step -method and piecewise linear finite elements on a tetrahedral of Process Systems Engineering, RWTH Aachen University c Chair of Heat Transfer and Air Conditioning, RWTH

  11. Inferring surface heat flux distributions guided by a global seismic model: particular application to Antarctica

    E-Print Network [OSTI]

    Shapiro, Nikolai

    -flow measurements are rare or entirely absent. This will result in a smooth global heat-flow map that may proveInferring surface heat flux distributions guided by a global seismic model: particular application to Antarctica Nikolai M. Shapiro*, Michael H. Ritzwoller Department of Physics, Center for Imaging the Earth

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

    E-Print Network [OSTI]

    Paik, Sokwon

    2006-08-16T23:59:59.000Z

    flux datum per one droplet. No spatial or temporal heat flux information was given. Klassen et al. [12] and di Marzo et al. [13] were the first to use an infrared thermography technique to attempt to measure the spatially and temporally resolved... infrared thermography. Because of the aforementioned limitation of the IR thermography, measurements were only possible outside of the droplets. Michiyoshi and Makino [15] used a dual beam synchroscope to measure the variation of the heater supply...

  13. Divertor heat and particle flux due to ELMs in DIII-D and ASDEX-Upgrade

    SciTech Connect (OSTI)

    Leonard, A.W.; Osborne, T.H. [General Atomics, San Diego, CA (United States); Suttrop, W. [Max Planck Inst. for Plasma Physics, Garching (Germany)] [and others

    1996-10-01T23:59:59.000Z

    The authors characterize the divertor target plate heat and particle fluxes that occur due to Edge-Localized-Modes (ELMs) during H-mode in DIII-D and ASDEX-Upgrade. During steady-state ELMing H-mode the fraction of main plasma stored energy lost with each ELM varies from 6% to 2% as input power increases above the H-mode power threshold. The ELM energy is deposited near the strikepoints on the divertor target plates in a fast time scale of {le} 1 ms. The spatial profile of the ELM heat pulse is flatter and broader, up to about a factor of 2, than that of the heat flux between ELMs. On ASDEX-Upgrade the inboard strike-point receives the greatest fraction, {ge} 75%, of ELM divertor heat flux, while on DIII-D the in/out split is nearly equal. The toroidal asymmetry of the heat pulse has produced a peaking factor on DIII-D of no more than 1.5. The particle flux, as measured by Langmuir probes, has also been found to be localized near the divertor strike-points. The increased particle flux during ELMs is a significant fraction of the total time-integrated divertor plate particle flux.

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

    SciTech Connect (OSTI)

    Nakos, James Thomas

    2005-12-01T23:59:59.000Z

    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.

  15. A multi-site analysis of random error in tower-based measurements of carbon and energy fluxes

    E-Print Network [OSTI]

    A multi-site analysis of random error in tower-based measurements of carbon and energy fluxes 2006 Abstract Measured surface-atmosphere fluxes of energy (sensible heat, H, and latent heat, LE of which include ``tall tower'' instrumentation), one grassland site, and one agricultural site, to conduct

  16. Flow instability and critical heat flux in a ribbed annulus

    SciTech Connect (OSTI)

    Yang, B.W.; Dougherty, T.; Fighetti, C.; Kokolis, S.; Reddy, G.D. [Columbia Univ., New York, NY (United States); McAssey, E.V. Jr. [Villanova Univ., PA (United States); Coutts, A. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1993-11-01T23:59:59.000Z

    An experimental program has been conducted to determine the onset of flow instability point in a heated annulus which is divided into four sub channels by non-conducting ribs. The onset of flow instability is identified by the minimum point in the pressure drop-velocity curve. Comparison with a ribless annulus show that the presence of ribs increases the minimum point velocity. In addition, data are presented which show that under certain conditions premature CHF can be induced by the ribs.

  17. 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]

    O'Hanley, Harrison Fagan

    2012-01-01T23:59:59.000Z

    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 ...

  18. Nanoscale modification of key surface parameters to augment pool boiling heat transfer and critical heat flux in water and dielectric fluids

    E-Print Network [OSTI]

    Forrest, Eric Christopher

    2009-01-01T23:59:59.000Z

    Surface effects on pool boiling heat transfer and the critical heat flux are well documented but poorly understood. This study investigates the pool boiling characteristics of various fluids, and demonstrates that surface ...

  19. Method and apparatus for determining vertical heat flux of geothermal field

    DOE Patents [OSTI]

    Poppendiek, Heinz F. (LaJolla, CA)

    1982-01-01T23:59:59.000Z

    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.

  20. New charged shear-free relativistic models with heat flux

    E-Print Network [OSTI]

    Y. Nyonyi; S. D. Maharaj; K. S. Govinder

    2014-12-21T23:59:59.000Z

    We study shear-free spherically symmetric relativistic gravitating fluids with heat flow and electric charge. The solution to the Einstein-Maxwell system is governed by the generalised pressure isotropy condition which contains a contribution from the electric field. This condition is a highly nonlinear partial differential equation. We analyse this master equation using Lie's group theoretic approach. The Lie symmetry generators that leave the equation invariant are found. The first generator is independent of the electromagnetic field. The second generator depends critically on the form of the charge, which is determined explicitly in general. We provide exact solutions to the gravitational potentials using the symmetries admitted by the equation. Our new exact solutions contain earlier results without charge. We show that other charged solutions, related to the Lie symmetries, may be generated using the algorithm of Deng. This leads to new classes of charged Deng models which are generalisations of conformally flat metrics.

  1. Divertor Heat Flux Amelioration in Highly-Shaped Plasma in NSTX

    SciTech Connect (OSTI)

    Soukhanovskii, V; Maingi, R; Gates, D; Menard, J; Raman, R; Bell, R; Bush, C; Kaita, R; Kugel, H; LeBlanc, B; Paul, S; Roquemore, A

    2007-07-02T23:59:59.000Z

    Steady-state handling of divertor heat flux is a critical issue for both the International Thermonuclear Experimental Reactor and spherical torus (ST) based devices with compact high power density divertors. The ST compact divertor with a small plasma volume, a small plasma-wetted area, and a short parallel connection length can reduce the operating space of heat flux dissipation techniques based on induced edge and/or scrape-off layer (SOL) power and momentum loss, such as the radiative and dissipative divertors and radiative mantles. Access to these regimes is studied in the National Spherical Torus Experiment (NSTX) with an open geometry horizontal carbon plate divertor in 2-6 MW NBI-heated H-mode plasmas in a lower single null (LSN) configuration in a range of elongations {kappa} = 1.8-2.4 and triangularities {delta}= 0.40-0.75. Experiments conducted in a lower end {kappa}{approx}1.8-2.0 and {delta}{approx} 0.4-0.5 LSN shape using deuterium injection in the divertor region have achieved the outer strike point (OSP) peak heat flux reduction from 4-6 MW/m2 to a manageable level of 1-2 MW/m2. However, only the high-recycling radiative divertor (RD) regime was found to be compatible with good performance and H-mode confinement. A partially detached divertor (PDD) could only be obtained at a high D2 injection rate that led to an X-point MARFE formation and confinement degradation. Also in the low {kappa}{approx} 2,{delta}{approx} 0.45 shape, peak heat flux q{sub pk} and heat flux width {lambda}{sub q} scaling studies have been conducted. Similar to tokamak divertor studies, q{sub pk} was found to be a strong function of input power PNBI and plasma current Ip, and the heat flux midplane scale length {lambda}{sub q} was found to be large as compared with simple SOL models. In this paper, we report on the first experiments to assess steady-state divertor heat flux amelioration in highly shaped plasmas in NSTX.

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

    E-Print Network [OSTI]

    Shiralkar, B. S.

    1968-01-01T23:59:59.000Z

    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 ...

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

    E-Print Network [OSTI]

    Kendall, Gail E.

    1978-01-01T23:59:59.000Z

    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 ...

  4. Eddy Correlation Flux Measurement System (ECOR) Handbook

    SciTech Connect (OSTI)

    Cook, DR

    2011-01-31T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Sprintall, Janet

    Near-Surface Eddy Heat and Momentum Fluxes in the Antarctic Circumpolar Current in Drake Passage Antarctic Circumpolar Current (ACC) momentum balance. The observations span 7 yr and are compared to eddy Current (ACC) pathway is marked by exceptionally high mesoscale eddy activity (e.g., Stammer 1998; Hughes

  6. Eddy Heat Flux in the Southern Ocean: Response to Variable Wind Forcing ANDREW MCC. HOGG

    E-Print Network [OSTI]

    Miami, University of

    Eddy Heat Flux in the Southern Ocean: Response to Variable Wind Forcing ANDREW MCC. HOGG Australian processes. The authors also test the model response to long-term changes in wind forcing, including steadily1925.1 © 2008 American Meteorological Society #12;Given the dominant role of wind forcing in the South

  7. High Heat Flux Erosion of Carbon Fibre Composite Materials in the TEXTOR Tokamak*

    E-Print Network [OSTI]

    Harilal, S. S.

    ,. 1. * . High Heat Flux Erosion of Carbon Fibre Composite Materials in the TEXTOR Tokamak Erosion of Carbon Fibre composite Materials in the TEXTOR Tokamak H. Bolt, T. Scholz, J. Boedo*, KH. The materials tested were carbon fibre reinforced materials w"th and without Si-addition. The probe w

  8. Heat Flux Manipulation with Engineered Thermal Materials Supradeep Narayana and Yuki Sato

    E-Print Network [OSTI]

    Sato, Yuki

    Heat Flux Manipulation with Engineered Thermal Materials Supradeep Narayana and Yuki Sato and constructed a new class of artificial materials for thermal conduction. We show that an engineered material materials. We demonstrate this concept by engineer- ing a new class of artificial material for thermal

  9. On the heat flux and entropy produced by thermal fluctuations S. Ciliberto1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    by an elastic force. Our results set strong constrains on the energy exchanged between coupled nano-systems held kept at different temperatures and coupled by an elastic force [13, 19]. Thus it gives more insight into the properties of the heat flux produced by mechanical coupling, in the famous Feymann ratchet [22­24] widely

  10. Multiphase Science and Technology, Vol. 13, No. 3, pp. 207-232, 2001 CRITICAL HEAT FLUX IN SUBCOOLED FLOW

    E-Print Network [OSTI]

    Kandlikar, Satish

    Multiphase Science and Technology, Vol. 13, No. 3, pp. 207-232, 2001 CRITICAL HEAT FLUX. Kandlikar Mechanical Engineering Department, Rochester Institute of Technology, Rochester, NY 14623, USA Abstract. Critical Heat Flux, or CHF, is an important condition that defines the upper limit of safe

  11. An analysis of pavement heat flux to optimize the1 water efficiency of a pavement-watering method2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    An analysis of pavement heat flux to optimize the1 water efficiency of a pavement-watering method2.hendel@paris.fr)8 9 Preprint version. Uploaded on May 12th , 2014.10 Abstract: Pavement-watering as a technique rarely been conducted. We propose an15 analysis of pavement heat flux at a depth of 5 cm and solar

  12. Effect of ocean surface currents on wind stress, heat flux, and wind power input to the ocean

    E-Print Network [OSTI]

    Thompson, LuAnne

    Effect of ocean surface currents on wind stress, heat flux, and wind power input to the ocean, J. T., and L. Thompson (2006), Effect of ocean surface currents on wind stress, heat flux, and wind power input to the ocean, Geophys. Res. Lett., 33, L09604, doi:10.1029/2006GL025784. 1. Introduction [2

  13. Inverse three-dimensional method for fast evaluation of temperature and heat flux fields during rolling process

    E-Print Network [OSTI]

    Boyer, Edmond

    is therefore needed. Therefore highly heterogeneous temperature fields and heat fluxes can be evaluating. Asymptotic developments enable to take into account variations of thermal properties depending on temperatureInverse three-dimensional method for fast evaluation of temperature and heat flux fields during

  14. Experimental investigation of nucleate boiling heat transfer mechanisms for cylinders in water and FC-72

    SciTech Connect (OSTI)

    Ammerman, C.N.; You, S.M.; Hong, Y.S. [Univ. of Texas, Arlington, TX (United States). Dept. of Mechanical and Aerospace Engineering

    1995-12-31T23:59:59.000Z

    A recently developed photographic method is used to quantify vapor volumetric flow rate above a boiling wire. The volumetric flow rate is combined with additional analyses to determine the overall contributions to the total heat flux from four nucleate boiling heat transfer mechanisms (latent heat, natural convection, Marangoni flow, and micro-convection). This technique is used to quantify the boiling heat transfer mechanisms versus heat flux for a 510-{micro}m wire immersed in saturated water and in water with a small amount of liquid soap added. These data are compared with similar data taken for a 75-{micro}m wire boiling in saturated FC-72. For all cases, latent heat is the dominant heat transfer mechanism in the fully developed nucleate boiling regime. In addition, the latent heat component is significantly increased by the addition of small amounts of soap (surfactant).

  15. Ultrahigh heat flux plasma-facing components for magnetic fusion energy

    SciTech Connect (OSTI)

    Youchison, D. L.

    2012-03-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2009-07-15T23:59:59.000Z

    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.

  17. Striation pattern of target particle and heat fluxes in three dimensional simulations for DIII-D

    SciTech Connect (OSTI)

    Frerichs, H.; Schmitz, O.; Reiter, D. [Institute of Energy and Climate Research—Plasma Physics, Forschungszentrum Jülich GmbH, Association EURATOM-FZJ, Partner in the Trilateral Euregio Cluster, Jülich (Germany)] [Institute of Energy and Climate Research—Plasma Physics, Forschungszentrum Jülich GmbH, Association EURATOM-FZJ, Partner in the Trilateral Euregio Cluster, Jülich (Germany); Evans, T. E. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)] [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Feng, Y. [Max-Planck Institute for Plasma Physics, Greifswald (Germany)] [Max-Planck Institute for Plasma Physics, Greifswald (Germany)

    2014-02-15T23:59:59.000Z

    The application of resonant magnetic perturbations results in a non-axisymmetric striation pattern of magnetic field lines from the plasma interior which intersect the divertor targets. The impact on related particle and heat fluxes is investigated by three dimensional computer simulations for two different recycling conditions (controlled via neutral gas pumping). It is demonstrated that a mismatch between the particle and heat flux striation pattern (splitting vs. no splitting), as is repeatedly observed in ITER similar shape H-mode plasmas at DIII-D, can be reproduced by the simulations for high recycling conditions at the onset of partial detachment. These results indicate that a detailed knowledge of the particle and energy balance is at least as important for realistic simulations as the consideration of a change in the magnetic field structure by plasma response effects.

  18. Parallel heat flux and flow acceleration in open field line plasmas with magnetic trapping

    SciTech Connect (OSTI)

    Guo, Zehua; Tang, Xian-Zhu; McDevitt, Chris [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-10-15T23:59:59.000Z

    The magnetic field strength modulation in a tokamak scrape-off layer (SOL) provides both flux expansion next to the divertor plates and magnetic trapping in a large portion of the SOL. Previously, we have focused on a flux expander with long mean-free-path, motivated by the high temperature and low density edge anticipated for an absorbing boundary enabled by liquid lithium surfaces. Here, the effects of magnetic trapping and a marginal collisionality on parallel heat flux and parallel flow acceleration are examined. The various transport mechanisms are captured by kinetic simulations in a simple but representative mirror-expander geometry. The observed parallel flow acceleration is interpreted and elucidated with a modified Chew-Goldberger-Low model that retains temperature anisotropy and finite collisionality.

  19. Uncertainty in calculated surface temperature and surface heat flux of THTF heater rods

    SciTech Connect (OSTI)

    Childs, K.W.

    1980-12-01T23:59:59.000Z

    This report presents a procedure for determining the uncertainty in the output of a complex computer code resulting from uncertainties in its input variables. This method is applied to ORINC (Oak Ridge Inverse Code) to estimate the uncertainty in the calculated surface temperature and surface heat flux of a THTF heater during a blowdown transient. The significant input variables are identified and 95% confidence bands are calculated for the code outputs based on the uncertainty in these input variables. 21 refs., 43 figs.

  20. Uncertainty in calculated surface temperature and surface heat flux of THTF heater rods

    SciTech Connect (OSTI)

    Childs, K.W.

    1980-12-01T23:59:59.000Z

    The report presents a procedure for determining the uncertainty in the output of a complex computer code resulting from uncertainties in its input variables. This method is applied to ORINC (Oak Ridge Inverse Code) to estimate the uncertainty in the calculated surface temperature and surface heat flux of a THTF heater during a blowdown transient. The significant input variables are identified and 95% confidence bands are calculated for the code outputs based on the uncertainty in these input variables.

  1. Evaluation of heat flux through blast furnace shell with attached sensors

    SciTech Connect (OSTI)

    Han, J.W. [Kyonggi Univ., Suwon, Kyonggi (Korea, Republic of). Dept. of Materials Engineering; Lee, J.H.; Suh, Y.K. [POSCO, Kwangyang, Cheonnam (Korea, Republic of). Technical Research Labs.

    1996-12-31T23:59:59.000Z

    Plant trials to evaluate heat fluxes through a lining/cooling system of a blast furnace were conducted in order to realize the cooling efficiency of the blast furnace under operation. For this purpose, several experiments to measure the in-furnace gas temperatures were cautiously made, and numerical simulations for the temperature distributions over the blast furnace shell and cooling/lining systems were also carried out.

  2. Development of probes for assessment of ion heat transport and sheath heat flux in the boundary of the Alcator C-Mod Tokamak

    E-Print Network [OSTI]

    Brunner, Daniel Frederic

    2013-01-01T23:59:59.000Z

    Progress towards a viable fusion reactor will require comprehensive understanding of boundary plasma physics. Knowledge in this area has been growing, yet there are critical gaps. Measurements of the sheath heat flux ...

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

    E-Print Network [OSTI]

    DeWitt, Gregory L

    2011-01-01T23:59:59.000Z

    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 ...

  4. Subsurface Temperature, Moisture, Thermal Conductivity and Heat Flux, Barrow, Area A, B, C, D

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

    Cable, William; Romanovsky, Vladimir

    Subsurface temperature data are being collected along a transect from the center of the polygon through the trough (and to the center of the adjacent polygon for Area D). Each transect has five 1.5m vertical array thermistor probes with 16 thermistors each. This dataset also includes soil pits that have been instrumented for temperature, water content, thermal conductivity, and heat flux at the permafrost table. Area C has a shallow borehole of 2.5 meters depth is instrumented in the center of the polygon.

  5. Analysis of Piston Heat Flux for Highly Complex Piston Shapes | Department

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1Albuquerque, NMPerformanceof Energy Piston Heat Flux for Highly

  6. Poloidal Inhomogeneity of the Particle Fluctuation Induced Fluxes near of the LCFS at Lower Hybrid Heating and Improved Confinement

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Hybrid Heating (LHH), when external (ETB) transport barrier followed by Internal (ITB) transport barrierPoloidal Inhomogeneity of the Particle Fluctuation Induced Fluxes near of the LCFS at Lower Hybrid Heating and Improved Confinement Transition at the FT - 2 Tokamak. S.I. Lashkul, S.V.Shatalin* , A

  7. The 2007 Bering Strait oceanic heat flux and anomalous Arctic sea-ice Rebecca A. Woodgate,1

    E-Print Network [OSTI]

    Lindsay, Ron

    flowing PW weakens the ice-pack thereby promoting more sea-ice motion in response to wind, which in turnThe 2007 Bering Strait oceanic heat flux and anomalous Arctic sea-ice retreat Rebecca A. Woodgate,1 sea-ice retreat, we use observational data to estimate Bering Strait volume and heat transports from

  8. The 2007 Bering Strait Oceanic Heat Flux and anomalous Arctic Sea-ice Retreat Rebecca A. Woodgate*, Tom Weingartner

    E-Print Network [OSTI]

    where heat carried by northward flowing PW weakens the ice-pack thereby promoting more sea-ice motionThe 2007 Bering Strait Oceanic Heat Flux and anomalous Arctic Sea-ice Retreat Rebecca A. Woodgate Abstract: To illuminate the role of Pacific Waters in the 2007 Arctic sea-ice retreat, we use observational

  9. Relativistic heat flux for a single component charged fluid in the presence of an electromagnetic field

    E-Print Network [OSTI]

    Garcia-Perciante, A L; Brun-Battistini, D

    2015-01-01T23:59:59.000Z

    Transport properties in gases are significantly affected by temperature. In previous works it has been shown that when the thermal agitation in a gas is high enough, such that relativistic effects become relevant, heat dissipation is driven not solely by a temperature gradient but also by other vector forces. In the case of relativistic charged fluids, a heat flux is driven by an electrostatic field even in the single species case. The present work generalizes such result by considering also a magnetic field in an arbitrary inertial reference frame. The corresponding constitutive equation is explicitly obtained showing that both electric and magnetic forces contribute to thermal dissipation. This result may lead to relevant effects in plasma dynamics.

  10. High-heat-flux removal by phase-change fluid and particulate flow

    SciTech Connect (OSTI)

    Gorbis, Z.R.; Raffray, A.R.; Abdou, M.A. (Univ. of California, Los Angeles (United States))

    1993-07-01T23:59:59.000Z

    A new concept based on particulate flow in which either or both the particulates and the fluid could undergo phase changes is proposed. The presence of particulates provides not only a mechanism for additional heat removal through phase change but also the potential for increasing the rate of heat transfer by enhancing convection through surface region/bulk [open quotes]mixing[close quotes], by enhancing radiation, particularly for high-temperature cases; and for the case of multiphase fluid, by enhancing the boiling process. One particularly interesting coolant system based on this concept is [open quotes]subcooled boiling water-ice particulate[close quotes] flow. A preliminary analysis of this coolant system is presented, the results of which indicate that such a coolant system is better applied for cooling of relatively small surface areas with high local heat fluxes, where a conventional cooling system would come short of providing the required heat removal at acceptable coolant pressure levels. 14 refs., 8 figs.

  11. Reduced model simulations of the scrape-off-layer heat-flux width and comparison with experiment

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

    Myra, J. R. [Lodestar Research Corporation, Boulder, CO (United States); Russell, D. A. [Lodestar Research Corporation, Boulder, CO (United States); D'Ippolito, D. A. [Lodestar Research Corporation, Boulder, CO (United States); Ahn, J- W [Oak Ridge National Lab., TN (United States); Maingi, R. [Oak Ridge National Lab., TN (United States); Maqueda, R. J. [Princeton Plasma Physics Lab., NJ (United States); Lundberg, D. P. [Princeton Plasma Physics Lab., NJ (United States); Stotler, D. P. [Princeton Plasma Physics Lab., NJ (United States); Zweben, S. J. [Princeton Plasma Physics Lab., NJ (United States); Boedo, J. [Univ. of California at San Diego, CA (United States); Umansky, M. [Lawrence Livermore National Lab., Livermore, CA (United States)

    2011-01-10T23:59:59.000Z

    Reduced model simulations of turbulence in the edge and scrape-off-layer (SOL) region of a spherical torus or tokamak plasma are employed to address the physics of the scrape-off-layer heat flux width. The simulation model is an electrostatic two-dimensional fluid turbulence model, applied in the plane perpendicular to the magnetic field at the outboard midplane of the torus. The model contains curvature-driven-interchange modes, sheath losses, and both perpendicular turbulent diffusive and convective (blob) transport. These transport processes compete with classical parallel transport to set the SOL width. Midplane SOL profiles of density, temperature and parallel heat flux are obtained from the simulation and compared with experimental results from the National Spherical Torus Experiment (NSTX) [S. M. Kaye, et al., Phys. Plasmas 8, 1977 (2001)] to study the scaling of the heat flux width with power and plasma current. It is concluded that midplane turbulence is the main contributor to the SOL heat flux width for the low power H-mode discharges studied, while additional physics is required to explain the plasma current scaling of the SOL heat flux width observed experimentally in higher power discharges. Intermittent separatrix spanning convective cells are found to be the main mechanism that sets the near-SOL width in the simulations. The roles of sheared flows and blob trapping vs. emission are discussed.

  12. Reduced model simulations of the scrape-off-layer heat-flux width and comparison with experiment

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

    Myra, J. R.; Russell, D. A.; D’Ippolito, D. A.; Ahn, J.-W.; Maingi, R.; Maqueda, R. J.; Lundberg, D. P.; Stotler, D. P.; Zweben, S. J.; Boedo, J.; et al

    2011-01-01T23:59:59.000Z

    Reduced model simulations of turbulence in the edge and scrape-off-layer (SOL) region of a spherical torus or tokamak plasma are employed to address the physics of the scrape-off-layer heat flux width. The simulation model is an electrostatic two-dimensional fluid turbulence model, applied in the plane perpendicular to the magnetic field at the outboard midplane of the torus. The model contains curvature-driven-interchange modes, sheath losses, and both perpendicular turbulent diffusive and convective (blob) transport. These transport processes compete with classical parallel transport to set the SOL width. Midplane SOL profiles of density, temperature and parallel heat flux are obtained from themore »simulation and compared with experimental results from the National Spherical Torus Experiment (NSTX) to study the scaling of the heat flux width with power and plasma current. It is concluded that midplane turbulence is the main contributor to the SOL heat flux width for the low power H-mode discharges studied, while additional physics is required to explain the plasma current scaling of the SOL heat flux width observed experimentally in higher power discharges. Intermittent separatrix spanning convective cells are found to be the main mechanism that sets the near-SOL width in the simulations. The roles of sheared flows and blob trapping vs. emission are discussed.« less

  13. International Lige Colloquium on Ocean Dynamics, GAS TRANSFER AT WATER SURFACES, May 2 -6 2005 Estimation of air-sea gas and heat fluxes from infrared imagery and

    E-Print Network [OSTI]

    Jaehne, Bernd

    2005 Estimation of air-sea gas and heat fluxes from infrared imagery and surface wave measurements and much higher heat fluxes. In addition, the infrared imagery analysis reveals potentially significant the infrared images. It is also shown that the difference in the surface boundary conditions for heat and gas

  14. The following are typical equations and conversions for calculating flux densities of sensible, latent and carbon dioxide from eddy covariances presented by Kevin Tu, St. Louis (10/97). The

    E-Print Network [OSTI]

    Tu, Kevin

    , latent and carbon dioxide from eddy covariances presented by Kevin Tu, St. Louis (10/97). The properties

  15. Secondary electron emission and the bifurcation of the heat flux to the targets in fusion plasmas

    SciTech Connect (OSTI)

    Lee, Wonjae; Krasheninnikov, Sergei I. [University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093 (United States)] [University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093 (United States)

    2013-12-15T23:59:59.000Z

    The presence of secondary electron emission (SEE) from plasma facing components in fusion devices can result in a strong localization of the heat flux from plasma to the wall and subsequent wall erosion. Usually, the impact of the SEE is considered assuming the Maxwellian distribution of the electrons coming to the surface. As a result, the SEE coefficient only depends on the temperature of primary electrons. However, the tail of primary electron distribution function in the scrape off layer (SOL) of fusion devices can be far from Maxwellian due to preferential loss of fast electrons. Consequently, it is shown that the SEE coefficient will depend on the wall potential and multiple solutions can be possible corresponding to different regimes of plasma flow to the wall: with and without SEE effects. This effect can cause two-slope electron temperature profiles in the SOL, which are often seen in experiments.

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

    E-Print Network [OSTI]

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

    2013-01-01T23:59:59.000Z

    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.

  17. Divertor Heat Flux Mitigation in High-Performance H-mode Plasmas in the National Spherical Torus Experiment.

    SciTech Connect (OSTI)

    Soukhanovskii, V A; Maingi, R; Gates, D; Menard, J; Paul, S F; Raman, R; Roquemore, A L; Bell, R E; Bush, C; Kaita, R

    2008-09-22T23:59:59.000Z

    Experiments conducted in high-performance 1.0-1.2 MA 6 MW NBI-heated H-mode plasmas with a high flux expansion radiative divertor in NSTX demonstrate that significant divertor peak heat flux reduction and access to detachment may be facilitated naturally in a highly-shaped spherical torus (ST) configuration. Improved plasma performance with high {beta}{sub p} = 15-25%, a high bootstrap current fraction f{sub BS} = 45-50%, longer plasma pulses, and an H-mode regime with smaller ELMs has been achieved in the lower single null configuration with higher-end elongation 2.2-2.4 and triangularity 0.6-0.8. Divertor peak heat fluxes were reduced from 6-12 MW/m{sup 2} to 0.5-2 MW/m{sup 2} in ELMy H-mode discharges using high magnetic flux expansion and partial detachment of the outer strike point at several D{sub 2} injection rates, while good core confinement and pedestal characteristics were maintained. The partially detached divertor regime was characterized by a 30-60% increase in divertor plasma radiation, a peak heat flux reduction by up to 70%, measured in a 10 cm radial zone, a five-fold increase in divertor neutral pressure, and a significant volume recombination rate increase.

  18. Columbia University flow instability experimental program: Volume 7. Single tube tests, critical heat flux test program

    SciTech Connect (OSTI)

    Dougherty, T.; Maciuca, C.; McAssey, E.V. Jr.; Reddy, D.G.; Yang, B.W.

    1992-09-01T23:59:59.000Z

    This report deals with critical heat flux (CHF) measurements in vertical down flow of water at low pressures in a round Inconel tube, 96 inches long and 0.62 inch inside diameter. A total of 28 CHF points were obtained. These data were found to correlate linearly with the single variable q, defined as the heat flux required to raise the enthalpy from the inlet value to the saturation value. These results were compared to the published results of Swedish investigators for vertical upflow of water at low pressures in round tubes of similar diameters and various lengths. The parameter q depends on the inlet enthalpy and is a nonlocal variable, thus this correlation is nonlocal unless the coefficients depend upon tube length in a particular prescribed manner. For the low pressure Swedish data, the coefficients are practically independent of length and hence the correlation is nonlocal. In the present investigation only one length was employed, so it is not possible to determine whether the correlation for these data is local or nonlocal, although there is reason to believe that it is local. The same correlation was applied to a large data base (thousands of CHF points) compiled from the published data of a number of groups and found to apply, with reasonable accuracy over a wide range of conditions, yielding sometimes local and sometimes nonlocal correlations. The basic philosophy of data analysis here was not to generate a single correlation which would reproduce all data, but to search for correlations which apply adequately over some range and which might have some mechanistic significance. The tentative conclusion is that at least two mechanisms appear operative, leading to two types of correlations, one local, the other nonlocal.

  19. Thermal Transistor: Heat Flux Switching and Modulating Wei Chung LO1;4

    E-Print Network [OSTI]

    Li, Baowen

    is an efficient heat control device which can act as a heat switch as well as a heat modulator. In this paper, we

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

    E-Print Network [OSTI]

    Danforth, Chris

    . 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

  1. US-Japan workshop Q-181 on high heat flux components and plasma-surface interactions for next devices: Proceedings

    SciTech Connect (OSTI)

    McGrath, R.T. [ed.] [Sandia National Labs., Albuquerque, NM (United States)] [ed.; Sandia National Labs., Albuquerque, NM (United States); Yamashina, T. [ed.] [Hokkadio Univ. (Japan)] [ed.; Hokkadio Univ. (Japan)

    1994-04-01T23:59:59.000Z

    This report contain viewgraphs of papers from the following sessions: plasma facing components issues for future machines; recent PMI results from several tokamaks; high heat flux technology; plasma facing components design and applications; plasma facing component materials and irradiation damage; boundary layer plasma; plasma disruptions; conditioning and tritium; and erosion/redeposition.

  2. Surface energy budget over the South Pole and turbulent heat fluxes as a function of an empirical bulk Richardson number

    E-Print Network [OSTI]

    Walden, Von P.

    as a residual of the energy budget, temperature inversion strength, and wind shear as a function of the bulkSurface energy budget over the South Pole and turbulent heat fluxes as a function of an empirical 2009; accepted 12 August 2009; published 26 November 2009. [1] Routine radiation and meteorological

  3. Pressure tensor and heat flux vector for inhomogeneous nonequilibrium fluids under the influence of three-body forces

    E-Print Network [OSTI]

    coupled with the Axilrod-Teller three-body force. Our method of planes calculations agree perfectlyPressure tensor and heat flux vector for inhomogeneous nonequilibrium fluids under the influence of three-body forces Junfang Zhang and B. D. Todd* Centre for Molecular Simulation, Swinburne University

  4. Low heat flux and large variations of lithospheric thickness in the Canadian Shield

    E-Print Network [OSTI]

    Long, Bernard

    and require variations of heat supply to the lithosphere and/or radiogenic heat production in the lithospheric

  5. Decadal variations of global energy and ocean heat budget and meridional energy transports inferred from recent global data sets

    E-Print Network [OSTI]

    . Introduction [2] The total energy exchanges within the Earth climate system and their progressive or sometimes to accumulated ocean heat content do not show such good agreement, the former generally indicating a cooling over suggests that the latent heat flux anomalies are also too large (causing an overall cooling

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

    SciTech Connect (OSTI)

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

    1996-12-01T23:59:59.000Z

    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.

  7. Study on premixed combustion in cylindrical micro combustors: Transient flame behavior and wall heat flux

    SciTech Connect (OSTI)

    Li, J.; Chou, S.K.; Huang, G.; Yang, W.M. [Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576 (Singapore); Li, Z.W. [SSLS, National University of Singapore, 5 Research Link, Singapore 117603 (Singapore)

    2009-04-15T23:59:59.000Z

    The micro combustor is a key component of the micro thermophotovoltaic (TPV) system. Improving the wall temperature of the micro combustor is an effective way to elevate the system efficiency. An experimental study on the wall temperature and radiation heat flux of a series of cylindrical micro combustors (with a backward-facing step) was carried out. For the micro combustors with d = 2 mm, the regime of successful ignition (under the cold wall condition) was identified for different combustor lengths. Acoustic emission was detected for some cases and the emitted sound was recorded and analyzed. Under the steady-state condition, the effects of the combustor diameter (d), combustor length (L), flow velocity (u{sub 0}) and fuel-air equivalence ratio ({phi}) on the wall temperature distribution were investigated by measuring the detailed wall temperature profiles. In the case that the micro combustor is working as an emitter, the optimum efficiency was found at {phi} {approx} 0.8, independent of the combustor dimensions (d and L) and the flow velocity. Under the experimental conditions employed in the present study, the positions of the peak wall temperature were found to be about 8-11 mm and 4-6 mm from the step for the d = 3 mm and d = 2 mm micro combustors, respectively, which are 8-11 and 8-12 times of their respective step heights. This result suggests that the backward-facing step employed in the combustor design is effective in stabilizing the flame position. (author)

  8. Determination of the magnetocaloric entropy change by field sweep using a heat flux setup

    SciTech Connect (OSTI)

    Monteiro, J. C. B., E-mail: jolmiui@gmail.com; Reis, R. D. dos; Mansanares, A. M.; Gandra, F. G. [Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin, Campinas, SP 13083-859 (Brazil)

    2014-08-18T23:59:59.000Z

    We report on a simple setup using a heat flux sensor adapted to a Quantum Design Physical Property Measurement System to determine the magnetocaloric entropy change (?S). The major differences for the existing setups are the simplicity of this assembly and the ease to obtain the isothermal entropy change either by a field sweep or a temperature sweep process. We discuss the use of these two processes applied to Gd and Gd{sub 5}Ge{sub 2}Si{sub 2} samples. The results are compared to the temperature sweep measurements and they show the advantages of this setup and of the field sweep procedure. We found a significant reduction of ?S and on the refrigerating cooling power (RCP) at low field changes in a field sweep process when the sample is not driven to the same initial state for each temperature. We show that the field sweep process without any measuring protocol is the only correct way to experimentally determine ?S and RCP for a practical regenerative refrigerator.

  9. High-resolution quantification of groundwater flux using a heat tracer: laboratory sandbox tests

    E-Print Network [OSTI]

    Konetchy, Brant Evan

    2014-12-31T23:59:59.000Z

    Groundwater flux is the most critical factor controlling contaminant transport in aquifers. High-resolution information about groundwater flux and its variability is essential to properly assessing and remediating contamination sites. Recently, we...

  10. Testing above-and below-canopy representations of turbulent fluxes in an energy balance snowmelt model

    E-Print Network [OSTI]

    Tarboton, David

    Testing above- and below-canopy representations of turbulent fluxes in an energy balance snowmelt and latent heat are important processes in the surface energy balance that drives snowmelt. Modeling in an energy balance snowmelt model, Water Resour. Res., 49, doi:10.1002/wrcr.20073. 1. Introduction [2

  11. Flexible Macroscopic Models for Dense-Fluid Shockwaves: Partitioning Heat and Work; Delaying Stress and Heat Flux; Two-Temperature Thermal Relaxation

    E-Print Network [OSTI]

    Wm. G. Hoover; Carol G. Hoover; Francisco J. Uribe

    2010-05-10T23:59:59.000Z

    Macroscopic models which distinguish the longitudinal and transverse temperatures can provide improved descriptions of the microscopic shock structures as revealed by molecular dynamics simulations. Additionally, we can include three relaxation times in the models, two based on Maxwell's viscoelasticity and its Cattaneo-equation analog for heat flow, and a third thermal, based on the Krook-Boltzmann equation. This approach can replicate the observed lags of stress (which lags behind the strain rate) and heat flux (which lags behind the temperature gradient), as well as the eventual equilibration of the two temperatures. For profile stability the time lags cannot be too large. By partitioning the longitudinal and transverse contributions of work and heat and including a tensor heat conductivity and bulk viscosity, all the qualitative microscopic features of strong simple-fluid shockwave structures can be reproduced.

  12. Identification of pool boiling heat transfer mechanisms in FC-72 using a single-photo method

    SciTech Connect (OSTI)

    Ammerman, C.N.; You, S.M.; Hong, Y.S. [Univ. of Texas, Arlington, TX (United States). Dept. of Mechanical and Aerospace Engineering

    1995-10-01T23:59:59.000Z

    A unique method to determine the vapor flow rate above a boiling cylinder utilizing a single photograph is developed and discussed. This method is applied to a 75-{micro}m wire immersed in a saturated, highly wetting liquid (FC-72) to determine bubble departure diameter, frequency, and nucleation site density. Using the experimental results, an analysis is performed to evaluate individual heat flux contributions of the four pool boiling mechanisms: latent heat, natural convection, Marangoni flow, and micro-convection. Latent heat is identified as the dominant mechanism throughout most of the nucleate boiling regime.

  13. 316 J. RULLA AND R.E. SHOWALTER constant on each of u 0. Thus, the heat flux in the fissures is given by Fourier's

    E-Print Network [OSTI]

    ~ eand ~ is a measure of the degree of fissuring. Conservation of heat energy computed respectively with the volume exchange rate. In (Lb) occurs the dual situation in which the storage of heat in the fissure#12;316 J. RULLA AND R.E. SHOWALTER constant on each of u 0. Thus, the heat flux

  14. About the conditions of suppression of turbulence effects on the poloidal fluxes in thoroidal plasmas in the presence of RF heating

    E-Print Network [OSTI]

    plasmas in the presence of RF heating N. Pometescu University of Craiova, Association EURATOM of the poloidal particle and heat fluxes in the thoroidal plasmas due to electrostatic turbulence in the presence of external Radio Frequency heating. The effects of the electrostatic turbulence contain two terms. One

  15. 598 IEEE TRANSACTIONS ON COMPONENTS AND PACKAGING TECHNOLOGIES, VOL. 26, NO. 3, SEPTEMBER 2003 Thermal Design Methodology for High-Heat-Flux

    E-Print Network [OSTI]

    Qu, Weilin

    598 IEEE TRANSACTIONS ON COMPONENTS AND PACKAGING TECHNOLOGIES, VOL. 26, NO. 3, SEPTEMBER 2003 Thermal Design Methodology for High-Heat-Flux Single-Phase and Two-Phase Micro-Channel Heat Sinks Weilin of single-phase and two-phase micro-channel heat sinks. The first part of the paper concerns single

  16. Divertor Heat Flux Mitigation in High-Performance H-mode Discharges in the National Spherical Torus Experiment.

    SciTech Connect (OSTI)

    Soukhanovskii, V A; Maingi, R; Gates, D; Menard, J

    2008-12-31T23:59:59.000Z

    Experiments conducted in high-performance 1.0 MA and 1.2 MA 6 MW NBI-heated H-mode discharges with a high magnetic flux expansion radiative divertor in NSTX demonstrate that significant divertor peak heat flux reduction and access to detachment may be facilitated naturally in a highly-shaped spherical torus (ST) configuration. Improved plasma performance with high {beta}{sub t} = 15-25%, a high bootstrap current fraction f{sub BS} = 45-50%, longer plasma pulses, and an H-mode regime with smaller ELMs has been achieved in the strongly-shaped lower single null configuration with elongation {kappa} = 2.2-2.4 and triangularity {delta} = 0.6-0.8. Divertor peak heat fluxes were reduced from 6-12 MW/m{sup 2} to 0.5-2 MW/m{sup 2} in ELMy H-mode discharges using the inherently high magnetic flux expansion f{sub m} = 16-25 and the partial detachment of the outer strike point at several D{sub 2} injection rates. A good core confinement and pedestal characteristics were maintained, while the core carbon concentration and the associated Z{sub eff} were reduced. The partially detached divertor regime was characterized by an increase in divertor radiated power, a reduction of ion flux to the plate, and a large neutral compression ratio. Spectroscopic measurements indicated a formation of a high-density, low temperature region adjacent to the outer strike point, where substantial increases in the volume recombination rate and CII, CIII emission rates was measured.

  17. Simulation of Strongly Heated Internal Gas Flows Using a Near-Wall Two-Equation Heat Flux Model

    SciTech Connect (OSTI)

    Richards, Adam H.; Spall, Robert E. [Utah State University, 1400 Old Main Hill Logan, Utah 84322-1400 (United States)

    2006-07-01T23:59:59.000Z

    A two-equation k-{omega} model is used to model a strongly heated, low-Mach number gas flowing upward in a vertical tube. Heating causes significant property variation and thickening of the viscous sublayer, consequently a fully developed flow does not evolve. Two-equation turbulence models generally perform poorly under such conditions. Consequently, in the present work, a near-wall two-equation heat transfer model is utilized in conjunction with the k-{omega} model to improve heat transfer predictions. (authors)

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

    E-Print Network [OSTI]

    Rohsenow, Warren M.

    1951-01-01T23:59:59.000Z

    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 ...

  19. Division of Development and Technology Plasma/Materials Interaction and High Heat Flux Materials and Components Task Groups: Report on the joint meeting, July 9, 1986

    SciTech Connect (OSTI)

    Watson, R.D. (ed.)

    1986-09-01T23:59:59.000Z

    This paper contains a collection of viewgraphs from a joint meeting of the Division of Development and Technology Plasma/Materials Interaction and High Heat Flux Materials and Components Task Groups. A list of contributing topics is: PPPL update, ATF update, Los Alamos RFP program update, status of DIII-D, PMI graphite studies at ORNL, PMI studies for low atomic number materials, high heat flux materials issues, high heat flux testing program, particle confinement in tokamaks, helium self pumping, self-regenerating coatings technical planning activity and international collaboration update. (LSP)

  20. Report on the joint meeting of the Division of Development and Technology Plasma/Wall Interaction and High Heat Flux Materials and Components Task Groups

    SciTech Connect (OSTI)

    Wilson, K.L. (ed.)

    1985-10-01T23:59:59.000Z

    This report of the Joint Meeting of the Division of Development and Technology Plasma/Wall Interaction and High Heat Flux Materials and Components Task Groups contains contributing papers in the following areas: Plasma/Materials Interaction Program and Technical Assessment, High Heat Flux Materials and Components Program and Technical Assessment, Pumped Limiters, Ignition Devices, Program Planning Activities, Compact High Power Density Reactor Requirements, Steady State Tokamaks, and Tritium Plasma Experiments. All these areas involve the consideration of High Heat Flux on Materials and the Interaction of the Plasma with the First Wall. Many of the Test Facilities are described as well. (LSP)

  1. Natural convection in high heat flux tanks at the Hanford Waste Site / [by] Mark van der Helm and Mujid S. Kazimi

    E-Print Network [OSTI]

    Van der Helm, Mark Johan, 1972-

    1996-01-01T23:59:59.000Z

    A study was carried out on the potential for natural convection and the effect of natural convection in a High Heat Flux Tank, Tank 241-C-106, at the Hanford Reservation. To determine the existence of natural convection, ...

  2. EXPERIMENTAL STUDY OF CRITICAL HEAT FLUX WITH ALUMINA-WATER NANOFLUIDS IN DOWNWARD-FACING CHANNELS FOR IN-VESSEL RETENTION APPLICATIONS

    E-Print Network [OSTI]

    Park, R.J.

    The Critical Heat Flux (CHF) of water with dispersed alumina nanoparticles was measured for the geometry and flow conditions relevant to the In-Vessel Retention (IVR) situation which can occur during core melting sequences ...

  3. Constant-flux discrete heating in a unit aspect-ratio annulus This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Lopez, John M.

    Constant-flux discrete heating in a unit aspect-ratio annulus This article has been downloaded from to the journal homepage for more Home Search Collections Journals About Contact us My IOPscience #12;IOP.1088/0169-5983/44/6/065507 Constant-flux discrete heating in a unit aspect-ratio annulus J M Lopez1,2 , M Sankar3 and Younghae Do2 1

  4. Elastic thickness and heat flux estimates for the uranian satellite Ariel

    E-Print Network [OSTI]

    Peterson, G.; Nimmo, F.; Schenk, P.

    2015-01-01T23:59:59.000Z

    rotation, orbital states, energy sources, and heat transfera being the activation energy for ice creep, A the material5. Discussion The source of energy needed to produce our

  5. A comparison of the heat transfer capabilities of two manufacturing methods for high heat flux water-cooled devices

    SciTech Connect (OSTI)

    McKoon, R.H.

    1986-10-01T23:59:59.000Z

    An experimental program was undertaken to compare the heat transfer characteristics of water-cooled copper devices manufactured via conventional drilled passage construction and via a technique whereby molten copper is cast over a network of preformed cooling tubes. Two similar test blocks were constructed; one using the drilled passage technique, the other via casting copper over Monel pipe. Each test block was mounted in a vacuum system and heated uniformly on the top surface using a swept electron beam. From the measured absorbed powers and resultant temperatures, an overall heat transfer coefficient was calculated. The maximum heat transfer coefficient calculated for the case of the drilled passage test block was 2534 Btu/hr/ft/sup 2///sup 0/F. This corresponded to an absorbed power density of 320 w/cm/sup 2/ and resulted in a maximum recorded copper temperature of 346/sup 0/C. Corresponding figures for the cast test block were 363 Btu/hr/ft/sup 2///sup 0/F, 91 w/cm/sup 2/, and 453/sup 0/C.

  6. GEOPHYSICAL RESEARCH LETTERS, VOL. 40, 16, doi:10.1002/grl.50640, 2013 The role of the geothermal heat flux in driving the abyssal

    E-Print Network [OSTI]

    Ferrari, Raffaele

    . Peltier1 Received 24 April 2013; revised 4 June 2013; accepted 5 June 2013. [1] The results presented-induced circulation and the Antarctic bottom water cell. The enhanced circulation ven- tilates the GHF derived heating. R. Peltier (2013), The role of the geothermal heat flux in driving the abyssal ocean circulation

  7. Deep-Sea Research I 52 (2005) 519542 Davis Strait volume, freshwater and heat fluxes

    E-Print Network [OSTI]

    2005-01-01T23:59:59.000Z

    cycle is a complex combination of land runoff, precipitation, ice freezing­melting and input of salty that the freshwater flux coming out of Baffin Bay asso- ciated with the sea ice melting in that area repre- sents 70 to the melting of ice drifting with the shelf Labrador Current (Khatiwala et al., 2002). Hud- son Bay runoff

  8. Calculation of heat flux through a wall containing a cavity: comparison of several models

    SciTech Connect (OSTI)

    Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.

    1986-02-01T23:59:59.000Z

    This paper describes the calculation of the heat transfer through the standard stud wall structure of a residential building. The wall cavity contains no insulation. Results from five test cases are presented. The first four represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using an improvement to the Implicit-Compressible Eulerian (ICE) algorithm of Harlow and Amsden. An algorithm is described to efficiently couple the fluid flow calculations to the radiation-conduction model for the solid portions of the system. Results indicate that conduction through still plates contributes less than 2% of the total heat transferred through a composite wall. All of the other elements (conduction through wall board, sheathing, and siding; convection from siding and wallboard to ambients; and radiation across the wall cavity) are required to accurately predict the heat transfer through a wall. Addition of a foil liner on one inner surface of the wall cavity reduces the total heat transferred by almost 50%.

  9. Collapse of a relativistic self-gravitating star with radial heat flux: Impact of anisotropic stresses

    E-Print Network [OSTI]

    Sharma, Ranjan

    2013-01-01T23:59:59.000Z

    We develop a simple model for a self-gravitating spherically symmetric relativistic star which begins to collapse from an initially static configuration by dissipating energy in the form of radial heat flow. We utilize the model to show how local anisotropy effects the collapse rate and thermal behaviour of gravitationally evolving systems.

  10. Collapse of a relativistic self-gravitating star with radial heat flux: Impact of anisotropic stresses

    E-Print Network [OSTI]

    Ranjan Sharma; Shyam Das

    2013-04-28T23:59:59.000Z

    We develop a simple model for a self-gravitating spherically symmetric relativistic star which begins to collapse from an initially static configuration by dissipating energy in the form of radial heat flow. We utilize the model to show how local anisotropy effects the collapse rate and thermal behaviour of gravitationally evolving systems.

  11. On the heat flux and entropy produced by thermal fluctuations S. Ciliberto1

    E-Print Network [OSTI]

    by an elastic force. Our results set strong constrains on the energy exchanged between coupled nano-systems kept on systems in contact with a single heat bath and driven out-of-equilibrium by external forces or fields [3 Brownian particles kept at different temperatures and coupled by an elastic force [11, 12]. Thus it gives

  12. Multi-scale Control and Enhancement of Reactor Boiling Heat Flux by Reagents and Nanoparticles

    SciTech Connect (OSTI)

    Manglik, R M; Athavale, A; Kalaikadal, D S; Deodhar, A; Verma, U

    2011-09-02T23:59:59.000Z

    The phenomenological characterization of the use of non-invasive and passive techniques to enhance the boiling heat transfer in water has been carried out in this extended study. It provides fundamental enhanced heat transfer data for nucleate boiling and discusses the associated physics with the aim of addressing future and next-generation reactor thermal-hydraulic management. It essentially addresses the hypothesis that in phase-change processes during boiling, the primary mechanisms can be related to the liquid-vapor interfacial tension and surface wetting at the solidliquid interface. These interfacial characteristics can be significantly altered and decoupled by introducing small quantities of additives in water, such as surface-active polymers, surfactants, and nanoparticles. The changes are fundamentally caused at a molecular-scale by the relative bulk molecular dynamics and adsorption-desorption of the additive at the liquid-vapor interface, and its physisorption and electrokinetics at the liquid-solid interface. At the micro-scale, the transient transport mechanisms at the solid-liquid-vapor interface during nucleation and bubblegrowth can be attributed to thin-film spreading, surface-micro-cavity activation, and micro-layer evaporation. Furthermore at the macro-scale, the heat transport is in turn governed by the bubble growth and distribution, macro-layer heat transfer, bubble dynamics (bubble coalescence, collapse, break-up, and translation), and liquid rheology. Some of these behaviors and processes are measured and characterized in this study, the outcomes of which advance the concomitant fundamental physics, as well as provide insights for developing control strategies for the molecular-scale manipulation of interfacial tension and surface wetting in boiling by means of polymeric reagents, surfactants, and other soluble surface-active additives.

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

    SciTech Connect (OSTI)

    Lowe, K.T.

    2005-10-07T23:59:59.000Z

    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.

  14. High heat flux testing of a two-tube copper panel specimen for LLNL at ASURF

    SciTech Connect (OSTI)

    Easoz, J.R.; Sink, D.A.

    1984-12-01T23:59:59.000Z

    This letter documents the results of the test program conducted for Lawrence Livermore National Laboratory (LLNL) by Westinghouse Advanced Energy Systems Division (AESD) in fulfillment of the Third Amendment to Subcontract 9125401. The original test matrix of 20,000 heating cycles on two test articles called for in the contract was not technically feasible due to the inability of the test articles supplied by LLNL to perform successfully at the required test conditions. Burnout occurred in one of the tubes of a two-tube target during the first series of tests. As a result, the work scope was changed by LLNL such that the tests on the milled copper plate panel specimen were replaced by a second set of heating tests on the second tube of the two-tube copper panel specimen to confirm the conditions for burnout failure. The testing requirements were completed following failure of the second tube at nominally identical conditions under which the first tube failed, and verification of these conditions. This letter completes all contractual obligations by serving as the final report on the test program.

  15. Plasma-Materials Interactions (PMI) and High-Heat-Flux (HHF) component research and development in the US Fusion Program

    SciTech Connect (OSTI)

    Conn, R.W.

    1986-10-01T23:59:59.000Z

    Plasma particle and high heat fluxes to in-vessel components such as divertors, limiters, RF launchers, halo plasma scrapers, direct converters, and wall armor, and to the vacuum chamber itself, represent central technical issues for fusion experiments and reactors. This is well recognized and accepted. It is also well recognized that the conditions at the plasma boundary can directly influence core plasma confinement. This has been seen most dramatically, on the positive side, in the discovery of the H-mode using divertors in tokamaks. It is also reflected in the attention devoted worldwide to the problems of impurity control. Nowadays, impurities are controlled by wall conditioning, special discharge cleaning techniques, special coatings such as carbonization, the use of low-Z materials for limiters and armor, a careful tailoring of heat loads, and in some machines, through the use of divertors. All programs, all experiments, and all designers are now keenly aware that PMI and HHF issues are key to the successful performance of their machines. In this brief report we present general issues in Section 2, critical issues in Section 3, existing US PMI/HHF experiments and facilities in Section 4, US International Cooperative PMI/HHF activities in Section 5, and conclude with a discussion on major tasks in PMI/HHF in Section 6.

  16. The Surface Energy Balance System (SEBS) for estimation of turbulent heat fluxes Hydrology and Earth System Sciences, 6(1), 8599 (2002) EGS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    The Surface Energy Balance System (SEBS) for estimation of turbulent heat fluxes 85 Hydrology and Earth System Sciences, 6(1), 85­99 (2002) © EGS The Surface Energy Balance System (SEBS) for estimation, The Netherlands Email: B.su@Alterra.wag-ur.nl Abstract A Surface Energy Balance System (SEBS) is proposed

  17. Please cite this article in press as: I. Mazul, et al., Russian development of enhanced heat flux technologies for ITER first wall, Fusion Eng. Des. (2012), doi:10.1016/j.fusengdes.2011.12.005

    E-Print Network [OSTI]

    Raffray, A. René

    2012-01-01T23:59:59.000Z

    .elsevier.com/locate/fusengdes Russian development of enhanced heat flux technologies for ITER first wall I. Mazula, , A. Alekseeva , VPlease cite this article in press as: I. Mazul, et al., Russian development of enhanced heat flux technologies for ITER first wall, Fusion Eng. Des. (2012), doi:10.1016/j.fusengdes.2011.12.005 ARTICLE IN PRESS

  18. Subantarctic Mode Water formation : air-sea fluxes and cross-frontal exchange

    E-Print Network [OSTI]

    Holte, James

    2010-01-01T23:59:59.000Z

    remote sensing data. The Kelly latent and sensible heatRemote Sensing Obser- vations (J-OFURO), Kelly, OAFlux, and the Southern Ocean State Estimate (SOSE). The heat

  19. Validation/Uncertainty Quantification for Large Eddy Simulations of the heat flux in the Tangentially Fired Oxy-Coal Alstom Boiler Simulation Facility

    SciTech Connect (OSTI)

    Smith, P.J.; Eddings, E.G.; Ring, T.; Thornock, J.; Draper, T.; Isaac, B.; Rezeai, D.; Toth, P.; Wu, Y.; Kelly, K.

    2014-08-01T23:59:59.000Z

    The objective of this task is to produce predictive capability with quantified uncertainty bounds for the heat flux in commercial-scale, tangentially fired, oxy-coal boilers. Validation data came from the Alstom Boiler Simulation Facility (BSF) for tangentially fired, oxy-coal operation. This task brings together experimental data collected under Alstom’s DOE project for measuring oxy-firing performance parameters in the BSF with this University of Utah project for large eddy simulation (LES) and validation/uncertainty quantification (V/UQ). The Utah work includes V/UQ with measurements in the single-burner facility where advanced strategies for O2 injection can be more easily controlled and data more easily obtained. Highlights of the work include: • Simulations of Alstom’s 15 megawatt (MW) BSF, exploring the uncertainty in thermal boundary conditions. A V/UQ analysis showed consistency between experimental results and simulation results, identifying uncertainty bounds on the quantities of interest for this system (Subtask 9.1) • A simulation study of the University of Utah’s oxy-fuel combustor (OFC) focused on heat flux (Subtask 9.2). A V/UQ analysis was used to show consistency between experimental and simulation results. • Measurement of heat flux and temperature with new optical diagnostic techniques and comparison with conventional measurements (Subtask 9.3). Various optical diagnostics systems were created to provide experimental data to the simulation team. The final configuration utilized a mid-wave infrared (MWIR) camera to measure heat flux and temperature, which was synchronized with a high-speed, visible camera to utilize two-color pyrometry to measure temperature and soot concentration. • Collection of heat flux and temperature measurements in the University of Utah’s OFC for use is subtasks 9.2 and 9.3 (Subtask 9.4). Several replicates were carried to better assess the experimental error. Experiments were specifically designed for the generation of high-fidelity data from a turbulent oxy-coal flame for the validation of oxy-coal simulation models. Experiments were also conducted on the OFC to determine heat flux profiles using advanced strategies for O2 injection. This is important when considering retrofit of advanced O2 injection in retrofit configurations.

  20. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    temperature between the solar panel and the roof would havedirectly underneath the solar panel, and the temperatures ofsensor between the solar panel and the roof for the flush

  1. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01T23:59:59.000Z

    d b y t h e a n g l e d solar panel F i g u r e 62: C a l cK l e i s s l , C h a i r Solar panels were mounted w i t hthe optimal angles for solar panels [9], i n this study both

  2. 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 (OSTI)

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

    2011-01-19T23:59:59.000Z

    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.

  3. A TWO-PHASE HEAT SPREADER FOR COOLING HIGH HEAT FLUX SOURCES Mitsuo Hashimoto, Hiroto Kasai, Yuichi Ishida, Hiroyuki Ryoson, a

    E-Print Network [OSTI]

    -power lasers, high-intensity light-emitting diodes (LEDs), and semiconductor power devices. The heat spreader

  4. Distributed Generation with Heat Recovery and Storage

    E-Print Network [OSTI]

    Siddiqui, Afzal S.; Marnay, Chris; Firestone, Ryan M.; Zhou, Nan

    2008-01-01T23:59:59.000Z

    tiles for thermal energy storage,” working paper, Colorado1991). Wallboard with latent heat storage for passive solarR. (2000). Thermal energy storage for space cooling, Pacific

  5. The Conserved Penrose-Fife Phase Field Model with Special Heat Flux Laws and Memory E ects.

    E-Print Network [OSTI]

    Rocca, Elisabetta

    of one of the phases). The data g and h stand for the heat supply and the outer temperature; the function

  6. Definition of Total Energy budget equation in terms of moist-air Enthalpy surface flux

    E-Print Network [OSTI]

    Marquet, Pascal

    2015-01-01T23:59:59.000Z

    Uncertainty exists concerning the proper formulation of surface heat fluxes, namely the sum of "sensible" and "latent" heat fluxes, and in fact concerning these two fluxes if they are considered as separate fluxes. In fact, eddy flux of moist-air energy must be defined as the eddy transfer of moist-air specific enthalpy ($\\overline{w' h'}$), where the specific enthalpy ($h$) is equal to the internal energy of moist air plus the pressure divided by the density (namely $h = e_{\\rm int} + p/\\rho$). The fundamental issue is to compute this local (specific) moist-air enthalpy ($h$), and in particular to determine absolute reference value of enthalpies for dry air and water vapour $(h_d)_{\\rm ref}$ and $(h_v)_{\\rm ref}$. New results shown in Marquet (QJRMS 2015, arXiv:1401.3125) are based on the Third-law of Thermodynamics and can allow these computations. In this note, this approach is taken to show that Third-law based values of moist-air enthalpy fluxes is the sum of two terms. These two terms are similar to wha...

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

    SciTech Connect (OSTI)

    Jernigan, Dann A.; Blanchat, Thomas K.

    2010-09-01T23:59:59.000Z

    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.

  8. Project Profile: Heat Transfer and Latent Heat Storage in Inorganic...

    Energy Savers [EERE]

    Terrafore, under the Thermal Storage FOA, is developing an economically feasible thermal energy storage (TES) system based on phase change materials (PCMs), for CSP plants....

  9. Heat transfer in porous media with fluid phase changes

    SciTech Connect (OSTI)

    Su, H.J.

    1981-06-01T23:59:59.000Z

    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.

  10. Industrial Heat Pump Case Study

    E-Print Network [OSTI]

    Wagner, J. R.; Brush, F. C.

    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...

  11. Proceedings of 1999 U.S./Japan Workshop (99FT-05) On High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices

    SciTech Connect (OSTI)

    NYGREN,RICHARD E.; STAVROS,DIANA T.

    2000-06-01T23:59:59.000Z

    The 1999 US-Japan Workshop on High Heat Flux Components and Plasma Surface Interactions in Next Step Fusion Devices was held at the St. Francis Hotel in Santa Fe, New Mexico, on November 1-4, 1999. There were 42 presentations as well as discussion on technical issues and planning for future collaborations. The participants included 22 researchers from Japan and the United States as well as seven researchers from Europe and Russia. There have been important changes in the programs in both the US and Japan in the areas of plasma surface interactions and plasma facing components. The US has moved away from a strong focus on the ITER Project and has introduced new programs on use of liquid surfaces for plasma facing components, and operation of NSTX has begun. In Japan, the Large Helical Device began operation. This is the first large world-class confinement device operating in a magnetic configuration different than a tokamak. In selecting the presentations for this workshop, the organizers sought a balance between research in laboratory facilities or confinement devices related to plasma surface interactions and experimental research in the development of plasma facing components. In discussions about the workshop itself, the participants affirmed their preference for a setting where ''work-in-progress'' could be informally presented and discussed.

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

    SciTech Connect (OSTI)

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

    2012-08-10T23:59:59.000Z

    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.

  13. Intercomparison of Sensible Heat Flux from Large Aperture Scintillometer and Eddy Covariance Methods: Field Experiment over a Homogeneous Semi-arid Region

    E-Print Network [OSTI]

    Zeweldi, Dawit A.; Gebremichael, Mekonnen; Wang, Junming; Sammis, Theodore; Kleissl, Jan; Miller, David

    2010-01-01T23:59:59.000Z

    of satellite remote sensing sensible heat-?ux estimates dueremote sensing algorithms. A typical approach identi?es spectral bands particularly sensitive to surface heat ?

  14. ARM - Measurement - Sensible heat flux

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDCnarrowband upwellingpolarization ARM DatagovMeasurementsSensible

  15. A Latent Time-Budget Model

    E-Print Network [OSTI]

    Jan de Leeuw; Peter G.M. van der Heijden; Peter Verboon

    2011-01-01T23:59:59.000Z

    DE L E E U W (1989), Latent budget analysis, in: A. DECARLI,DER H E U D E N (1988), The analysis of time- budgets with alatent-time-budget model, in E. Diday et al. (eds. ), Data

  16. 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]

    Hall, Sharon J.

    in the modeling domain was calculated as part of the energy balance equation according to: E = a C CuM[qs(Tg) -qs MM5. The single urban category in the existing 25-category United States Geological Survey (USGS surface energy fluxes and ground temperature. Planetary boundary layer processes were included via the MRF

  17. Finite element analysis of conjugate heat transfer in axisymmetric pipe flows 

    E-Print Network [OSTI]

    Fithen, Robert Miller

    1987-01-01T23:59:59.000Z

    with no axial fluid conduction, such as liquid water at a moderate to high Reynolds number. Detailed fluid ? solid interface heat flux, Nusselt number, wall, and bulk temperatures for each case are presented. The results indicate axial wall conduction is very... model for a circular tube Comparison for constant heat flux case Comparison for constant temperature case Heat flux for Pe=5, constant heat flux case Heat flux for Pe=50, constant heat flux case Heat flux for Pe=200, constant heat flux case Heat...

  18. Development of an air-cooled, loop-type heat pipe with multiple condensers

    E-Print Network [OSTI]

    Kariya, H. Arthur (Harumichi Arthur)

    2012-01-01T23:59:59.000Z

    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 ...

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

    E-Print Network [OSTI]

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

    2006-01-01T23:59:59.000Z

    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...

  20. Coronal mass ejections and magnetic flux buildup in the heliosphere

    E-Print Network [OSTI]

    California at Berkeley, University of

    electron heat flux. The first panel shows the preeruption heliospheric flux, which consists of the an open the observed doubling in the magnetic field intensity at 1 AU over the solar cycle. Such timescales signatures; no flux buildup results. The dynamic simulation yields a solar cycle flux variation with high

  1. Solar heating system

    DOE Patents [OSTI]

    Schreyer, James M. (Oak Ridge, TN); Dorsey, George F. (Concord, TN)

    1982-01-01T23:59:59.000Z

    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.

  2. Improved solar heating systems

    DOE Patents [OSTI]

    Schreyer, J.M.; Dorsey, G.F.

    1980-05-16T23:59:59.000Z

    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.

  3. apple latent spherical: Topics by E-print Network

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

    Regarding Jones, Peter JS 102 Brain morphometry by probabilistic Latent Semantic Analysis Computer Technologies and Information Sciences Websites Summary: Brain morphometry by...

  4. Please cite this article in press as: S. Banetta, et al., Manufacturing of small-scale mock-ups and of a semi-prototype of the ITER Normal Heat Flux First Wall, Fusion Eng. Des. (2014), http://dx.doi.org/10.1016/j.fusengdes.2014.04.020

    E-Print Network [OSTI]

    Raffray, A. René

    2014-01-01T23:59:59.000Z

    Please cite this article in press as: S. Banetta, et al., Manufacturing of small-scale mock-ups homepage: www.elsevier.com/locate/fusengdes Manufacturing of small-scale mock-ups and of a semi the manufacturing development and fabrication of reduced scale ITER First Wall (FW) mock-ups of the Normal Heat Flux

  5. antineutrino flux measurements: Topics by E-print Network

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

    with Terrestrial Antineutrino Flux Measurements CERN Preprints Summary: Uranium and thorium are the main heat producing elements in the earth. Their quantities and...

  6. Segmentation and Enhancement of Latent Fingerprints: A Coarse to Fine Ridge

    E-Print Network [OSTI]

    a latent fingerprint image, a total variation (TV) decomposition model with L1 fidelity regularization INTRODUCTION LATENT fingerprints (or simply latents or finger marks) refer to fingerprints lifted from the sur

  7. Adding Domain Knowledge to Latent Topic Models Xiaojin Zhu

    E-Print Network [OSTI]

    Zhu, Xiaojin "Jerry"

    (Wisconsin) Knowledge LDA 5 / 42 #12;Some Topics by Latent Dirichlet Allocation (LDA) [Blei et al., JMLR by Latent Dirichlet Allocation (LDA) [Blei et al., JMLR 2003] p(word | topic) "troops" "election" "love influence [Gerrish & Blei, 2009] Matching papers to reviewers [Mimno & McCallum, 2007] Zhu (Wisconsin

  8. PUBLISHED ONLINE: 17 JULY 2011 | DOI: 10.1038/NGEO1205 Partial radiogenic heat model for Earth revealed

    E-Print Network [OSTI]

    Piepke, Andreas G.

    half of Earth's total heat flux. We therefore conclude that Earth's primordial heat supply has not yet

  9. Using Cool Roofs to Reduce Energy Use, Greenhouse Gas Emissions, and Urban Heat-island Effects: Findings from an India Experiment

    E-Print Network [OSTI]

    Akbari, Hashem

    2011-01-01T23:59:59.000Z

    49 Figure 26. Comparison of roof heat flux for East and West49 Figure 27. Roof heat flux vs. outside air temperature for8-19. 50 Figure 28. Roof heat flux vs. outside air

  10. Temperature profile of the infrared image Heat exchange between

    E-Print Network [OSTI]

    Jaehne, Bernd

    T Temperature profile of the infrared image Heat exchange between atmosphere and ocean References coefficient of heat in water determine the heat transfer velocity: *t Infrared images of the water surface: a-Karls-Universität Heidelberg www.uni-heidelberg.de Active controlled flux technique (ACFT) Continuous heat flux Periodic heat

  11. 3, 681705, 2006 Measurement and

    E-Print Network [OSTI]

    Boyer, Edmond

    and latent heat flux over the heterogeneous surface. Since 1970s, remote sensing technology has brought superiority to estimate areal sensible and latent heat flux over heterogenrous surface. For remote sensing temperature retrieved from remote sensing data and air temperature. Then latent heat flux can be calculated

  12. Disaggregating Cooling Energy Use of Commercial Buildings Into Sensible and Latent Fractions From Whole-Building Monitored Data: Methodology and Advantages

    E-Print Network [OSTI]

    Katipamula, S.; Reddy, T. A.; Claridge, D. E.

    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...

  13. Using Cool Roofs to Reduce Energy Use, Greenhouse Gas Emissions, and Urban Heat-island Effects: Findings from an India Experiment

    E-Print Network [OSTI]

    Akbari, Hashem

    2011-01-01T23:59:59.000Z

    heat fluxes, solar radiation, and electric power consumed byheat fluxes, solar radiation, and electric power consumed byheat fluxes, solar radiation, and electric power consumed by

  14. Transient-heat-transfer and stress analysis of a thermal-storage solar cooker module

    E-Print Network [OSTI]

    Zengeni, Hazel C

    2014-01-01T23:59:59.000Z

    This paper details the analysis carried out in Solidworks to determine the best material and configuration of a thermal-storage solar cooker module.The thermal-storage solar cooker utilizes the high-latent-heat lithium ...

  15. Optimization of the configuration and working fluid for a micro heat pipe thermal control device

    E-Print Network [OSTI]

    Coughlin, Scott Joseph

    2006-04-12T23:59:59.000Z

    Heat Pipe System : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 24 8 Illustration of Embedded Micro Heat Pipe Placement and Orientation 24 9 Thermal Circuit Model Taken from Original Design Illustration : : : 31 10 Thermal Circuit Model... latent heat (kJ=kg) ? length (m) ? viscosity (Ns=m2) ? ratio of speci?c heat ? Boltzmann constant (1:38 ? 10?23 m2kg=s2 ? K) ? density (kg=m3) ? latent heat (kJ=kg) ? kinematic viscosity (m2=s) ? surface tension (N=m) Subscripts a adiabatic b boiling c...

  16. ELM heat flux in the ITER divertor

    SciTech Connect (OSTI)

    Leonard, A.W.; Osborne, T.H. [General Atomics, San Diego, CA (United States); Hermann, A.; Suttrop, W. [Max Planck Inst. fuer Plasmaphysics (Germany); Itami, K. [Japan Atomic Energy Research Inst. (Japan); Lingertat, J. [JET Joint Undertaking, Abingdon (United Kingdom); Loarte, A. [Next European Torus, Garching (Germany)

    1998-07-01T23:59:59.000Z

    Edge-Localized-Modes (ELMs) have the potential to produce unacceptable levels of erosion of the ITER divertor. Ablation of the carbon divertor target will occur if the surface temperature rises above about 2,500 C. Because a large number of ELMs, {ge}1000, are expected in each discharge it is important that the surface temperature rise due to an individual ELM remain below this threshold. Calculations that have been carried out for the ITER carbon divertor target indicate ablation will occur for ELM energy {ge}0.5MJ/m{sup 2} if it is deposited in 0.1 ms, or 1.2 MJ/m{sup 2} if the deposition time is 1.0 ms. Since {Delta}T{proportional_to}Q{Delta}t{sup {minus}1/2}, an ablation threshold can be estimated at Q{Delta}t{sup {minus}1/2}{approx}45 MJm{sup {minus}2} s{sup {minus}1/2} where Q is the divertor ELM energy density in J-m{sup {minus}2} and {Delta}t is the time in seconds for that deposition. If a significant fraction of ELMs exceed this threshold then an unacceptable level of erosion may take place. The ablation parameter in ITER can be determined by scaling four factors from present experiments: the ELM energy loss from the core plasma, the fraction of ELM energy deposited on the divertor target, the area of the ELM profile onto the target, and the time for the ELM deposition. ELM data from JET, ASDEX-Upgrade, JT-60U, DIII-D and Compass-D have been assembled by the ITER Divertor Modeling and Database expert group into a database for the purpose of predicting these factors for ELMs in the ITER divertor.

  17. Energy Fluxes optimization for PV integrated Rim.Missaoui, Ghaith.Warkozek, Seddik. Bacha, Stphane.Ploix.

    E-Print Network [OSTI]

    Boyer, Edmond

    -time simulation I. NOMENCLATURE t Sampling step time, [hour]. Sampling time of the anticipatory layer. i, Ksun, : Constants. heater Heat flux given by the radiator. sun Heat flux of sunlight through the window

  18. Multi-Label Informed Latent Semantic Indexing , Shipeng Yu

    E-Print Network [OSTI]

    Tresp, Volker

    Multi-Label Informed Latent Semantic Indexing Kai Yu , Shipeng Yu , Volker Tresp Siemens AG, University of Munich, Germany kai.yu@siemens.com, volker.tresp@siemens.com, spyu

  19. A new correlation of the convective heat transfer coefficient between an air flow and a phase change material plate

    E-Print Network [OSTI]

    of phase change material (PCM). This correlation was built for the simulation of heat storage units: Convective heat transfer coefficient, correlation, phase change material, heat storage system, transient is the use of phase change materials (PCM). The latent heat which is needed for the material melting

  20. The latent effect of cogency in the minority influence process

    E-Print Network [OSTI]

    Ouellette, Judith A

    1993-01-01T23:59:59.000Z

    THE LATENT EFFECT OF COGENCY IN THE MINORITY INFLUENCE PROCESS A Thesis by JUDITH ANN OUELLETTE Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE May 1993 Major subject: Psychology THE LATENT EFFECT OF COGENCY IN THE MINORITY INFLUENCE PROCESS A Thesis by JUDITH ANN OUELLETTE Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment...

  1. Project Profile: Heat Transfer and Latent Heat Storage in Inorganic Molten

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOn April 23, 2014, an OHASeptember 2010 | DepartmentEnergy MITis PVSalts for CSP Plants

  2. Fast flux locked loop

    DOE Patents [OSTI]

    Ganther, Jr., Kenneth R. (Olathe, KS); Snapp, Lowell D. (Independence, MO)

    2002-09-10T23:59:59.000Z

    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.

  3. Proceedings of HT'03 2003 Summer Heat Transfer Conference

    E-Print Network [OSTI]

    Walker, D. Greg

    Proceedings of HT'03 2003 Summer Heat Transfer Conference July 21­23, 2003, Las Vegas, Nevada, USA HT2003-47016 A NEW TECHNIQUE FOR HEAT FLUX DETERMINATION D.G. Walker Department of Mechanical@vt.edu ABSTRACT A new method for estimating heat fluxes from heating rate measurements and an approach to measure

  4. Heat Transfer Derivation of differential equations for heat transfer conduction

    E-Print Network [OSTI]

    Veress, Alexander

    ) or kW *h or Btu. U is the change in stored energy, in units of kW *h (kWh) or Btu. qx is the heat conducted (heat flux) into the control volume at surface edge x, in units of kW/m2 or Btu/(h-ft2). qx volume is positive), in kW/m3 or Btu/(h-ft3) (a heat sink, heat drawn out of the volume, is negative

  5. A critical evaluation of the upper ocean heat budget in the Climate Forecast System Reanalysis data for the south central equatorial Pacific

    SciTech Connect (OSTI)

    Liu H.; Lin W.; Liu, X.; Zhang, M.

    2011-08-26T23:59:59.000Z

    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.

  6. World IMACS / MODSIM Congress, Cairns, Australia 13-17 July 2009 http://mssanz.org.au/modsim09

    E-Print Network [OSTI]

    Evans, Jason

    . Keywords: Land surface models, evapotranspiration, latent heat flux, satellite remote sensing Comparison of latent heat flux estimates over Australia Matthew F. McCabe1 , Yi Y. Liu1 , Raghuveer Vinukollu from such data do not contribute to model assessment and calibration. This study compares latent heat

  7. arabian sea due: Topics by E-print Network

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

    coupled feedback makes a non-trivial contribution substantially reduce the latent heat loss. The long-term latent heat flux change due to eddies in the model Jochum, Markus...

  8. Gas heat transfer in a heated vertical channel under deteriorated turbulent heat transfer regime

    E-Print Network [OSTI]

    Lee, Jeongik

    2007-01-01T23:59:59.000Z

    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 ...

  9. Gas Heat Transfer in a Heated Vertical Channel under Deteriorated Turbulent Heat Transfer Regime

    E-Print Network [OSTI]

    Lee, Jeongik

    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 ...

  10. Six-Week Time Series Of Eddy Covariance Co2 Flux At Mammoth Mountain...

    Open Energy Info (EERE)

    Flux At Mammoth Mountain, California- Performance Evaluation And Role Of Meteorological Forcing Abstract CO2 and heat fluxes were measured over a six-week period (09082006 to 10...

  11. Biogeosciences, 5, 421431, 2008 www.biogeosciences.net/5/421/2008/

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , into the fluxes of sensible and latent heat and heat storage con- trols the degree of coupling between the land covariance flux measurements of sensible and latent heat, soil heat flux, net radiation, above-ground phytomass and meteorological driv- ing forces energy partitioning was investigated at a temperate mountain

  12. Botryosphaeriaceae as endophytes and latent pathogens of woody plants: diversity, ecology and impact

    E-Print Network [OSTI]

    Review Botryosphaeriaceae as endophytes and latent pathogens of woody plants: diversity, ecology Keywords: Botryosphaeria Botryosphaeriaceae Emerging tree diseases Endophyte Latent pathogen Quarantine to general patterns observed for the collective of endophytes of woody plants. These include high levels

  13. Quantification of latent travel demand on new urban facilities in the state of Texas

    E-Print Network [OSTI]

    Henk, Russell H

    1989-01-01T23:59:59.000Z

    transportation facility was opened for use. The comparison of the photographs allowed for any changes in land use to be easily recognized. 15 Preliminar Anal sis of Variables Identification of Latent Travel Oemand The first step in this analysis of latent... facilities (3). Therefore, this highway characteristic was also included as a possible latent demand indicator. Detailed Anal sis of Variables In order to examine their relationships with latent travel demand on new urban transportation facilities...

  14. affecting carbon fluxes: Topics by E-print Network

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

    (IFN) (2 Paris-Sud XI, Universit de 43 High Heat Flux Erosion of Carbon Fibre Composite Materials in the TEXTOR Tokamak* Plasma Physics and Fusion Websites Summary: ,. 1. *...

  15. Latent-Descriptor Clustering for Unsupervised POS Induction Michael Lamar

    E-Print Network [OSTI]

    Bienenstock, Elie

    Latent-Descriptor Clustering for Unsupervised POS Induction Michael Lamar Department of Mathematics; Lamar et al., 2010; Reichart et al., 2010; Berg-Kirkpatrick et al., 2010). Some of these methods use papers advocate non- disambiguating models (Abend et al., 2010; Lamar et al., 2010): these assign

  16. Complexity of Inference in Latent Dirichlet David Sontag

    E-Print Network [OSTI]

    , document summarization, and classification [Blei and McAuliffe, 2008; Lacoste-Julien et al., 2009 of the simplest and most popular models, Latent Dirichlet Allocation (LDA) [Blei et al., 2003]. The LDA model on approximate inference algorithms for topic mod- els, such Gibbs sampling and variational inference [Blei et al

  17. Latent extinction risk and the future battlegrounds of mammal conservation

    E-Print Network [OSTI]

    Wilmers, Chris

    or where many species are thought to be at imminent risk of extinction. However, these strategies may identify such areas for the world's mammals using latent extinction risk, the discrepancy between a species' current extinction risk and that predicted from models on the basis of biological traits. Species

  18. Relationship between gradient and EM steps in latent variable models.

    E-Print Network [OSTI]

    Roweis, Sam

    includes random search, standard gradient­based algorithms, line search methods such as conjugate gradient to to first order method operat­ ing on the gradient of a locally reshaped likelihood function. DirectRelationship between gradient and EM steps in latent variable models. Ruslan Salakhutdinov Sam

  19. Relationship between gradient and EM steps in latent variable models.

    E-Print Network [OSTI]

    Roweis, Sam

    includes random search, standard gradient-based algorithms, line search methods such as conjugate gradient to to first order method operat- ing on the gradient of a locally reshaped likelihood function. DirectRelationship between gradient and EM steps in latent variable models. Ruslan Salakhutdinov Sam

  20. PUBLISHED VERSION ICRF heating in JET during initial operations with the ITER-like wall

    E-Print Network [OSTI]

    . Heat-fluxes on the protecting limiters close the antennas quantified using Infra-Red (IR) thermography

  1. Greening the terrestrial biosphere: simulated feedbacks on atmospheric heat and energy circulation

    E-Print Network [OSTI]

    Cowling, Sharon A.

    Greening the terrestrial biosphere: simulated feedbacks on atmospheric heat and energy circulation on atmospheric exchange of heat and moisture. Our CONTROL simulation had a mean global net primary production (NPP) of 56.3 GtCyr-1 which is half that of our scenario value of 115.1 GtCyr-1 . LAI and latent energy

  2. Enhanced heat transfer for thermionic power modules

    SciTech Connect (OSTI)

    Johnson, D.C.

    1981-07-01T23:59:59.000Z

    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.

  3. FLUX MEASUREMENTS FROM A TALL TOWER IN A COMPLEX LANDSCAPE

    SciTech Connect (OSTI)

    Kurzeja, R.; Weber, A.; Chiswell, S.; Parker, M.

    2010-07-22T23:59:59.000Z

    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.

  4. Varying trends in surface energy fluxes and associated climatebetween 1960-2002 based on transient climate simulations

    SciTech Connect (OSTI)

    Nazarenko, Larissa; Menon, Surabi

    2005-07-20T23:59:59.000Z

    The observed reduction in land surface radiation over the last several decades (1960-1990)---the so-called ''dimming effect''--- and the more recent evidence of a reversal in ''dimming'' over some locations beyond 1990 suggest several consequences on climate, notably on the hydrological cycle. Such a reduction in radiation should imply reduced surface temperature (Ts) and precipitation, which have not occurred. We have investigated the possible causes for the above climate features using a climate model coupled to a dynamic ocean model under natural and anthropogenic conditions. To isolate the aerosol influence on surface radiation trends, we have analyzed transient climate simulations from1960 to 2002 with and without anthropogenic aerosols. Based on a linear trend with aerosol effects included, the global mean change in the surface solar radiation absorbed over land is -0.021+-0.0033 Wm-2yr-1. Although the overall trend is negative, we do note a reversal in dimming after 1990, consistent with observations. Without aerosol effects, the surface solar radiation absorbed over land increases throughout 1960 to 2002, mainly due to the decrease in cloud cover associated with increased greenhouse warming. In spite of a simulated increase in Ts of 0.012 Kyr-1 for 1960 to 2002, the global mean latent heat flux and associated intensity of the hydrological cycle decrease overall, however with increases over some land locations due mainly to moisture advection. Simulated changes correspond more closely to observed changes when accounting for aerosol effects on climate.

  5. Heat Content Changes in the Pacific Ocean

    E-Print Network [OSTI]

    Frandsen, Jannette B.

    Heat Content Changes in the Pacific Ocean The Acoustic Thermometry of Ocean Cli- mate (ATOC assimilating ocean observations and changes expected from surface heat fluxes as measured by the daily National are a result of advection of heat by ocean currents. We calculate that the most likely cause of the discrepancy

  6. SchoolFEFLOW Exercise Heat extraction

    E-Print Network [OSTI]

    Kornhuber, Ralf

    the flux: q = 0.15 m/d Pumping (heat extraction) from aquifer and re-injection (of cooled water-injected water: 20°C · T = 20°C Model Extension #12;Summer SchoolHeat extraction from sloped aquifer 22Summer SchoolFEFLOW® Exercise Heat extraction from a sloped sandstone aquifer Vertical cross

  7. Spheromak reactor with poloidal flux-amplifying transformer

    DOE Patents [OSTI]

    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

    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.

  8. Atmospheric Neutrino Fluxes

    E-Print Network [OSTI]

    Thomas K. Gaisser

    2005-02-18T23:59:59.000Z

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

  9. Plasma momentum meter for momentum flux measurements

    DOE Patents [OSTI]

    Zonca, Fulvio (Rome, IT); Cohen, Samuel A. (Hopewell, NJ); Bennett, Timothy (Princeton, NJ); Timberlake, John R. (Allentown, NJ)

    1993-01-01T23:59:59.000Z

    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.

  10. Independent Control of Sensible and Latent Cooling in Small Buildings

    E-Print Network [OSTI]

    Andrews, J.; Lamontagne, J.; Piraino, M.

    1989-01-01T23:59:59.000Z

    ABSTRACT INDEPENDENT CONTROL OF SENSIBLE AND LATENT COOLING IN SMALL BUILDINGS~ J. ANDREWS, J. LAMONTAGNE, and M. PIRAINO Brookhaven National Laboratory Upton, New York This paper presents salient results of a utility-sponsored research project... characteristics used in the study are those found in a study of an energy- efficient Danish house which was constructed and monitored at Brookhaven National Laboratory (7). This house was found to have a natural air change rate of 0.1 air changes per hour...

  11. Heat Transfer Study of Polymer Solutions with Different Rigidities 

    E-Print Network [OSTI]

    Huang, Yao

    2014-05-08T23:59:59.000Z

    The heat transfer behaviors of non-Newtonian fluids under laminar flow conditions in circular tubes are presented in this study. The constant wall heat flux is considered as a boundary condition for dilute polymer solutions with different polymer...

  12. Transition boiling heat transfer from a horizontal surface

    E-Print Network [OSTI]

    Berenson Paul Jerome

    1960-01-01T23:59:59.000Z

    An experiment, utilising a condensing fluid as the heat source, was performed to determine the heat flux vs. temperature difference curve for transition pool boiling from a horisontal surface. The boiling cure was determined ...

  13. The porous media model for the hydraulic system of a conifer tree: linking sap flux data to1 transpiration rate2

    E-Print Network [OSTI]

    Soatto, Stefano

    hydraulic system but also11 requires a direct estimation of its properties. Our proposed PM model play a dominant role in controlling CO2 uptake and4 partitioning of net radiation between latent-atmosphere flux measurement networks6 and free air CO2 enrichment (FACE) experiments require a quantitative

  14. An evaluation of the thermal characteristics of a flat plate heat pipe spreader

    E-Print Network [OSTI]

    Chesser, Jason Blake

    2000-01-01T23:59:59.000Z

    An evaluation of the thermal characteristics of a flat plate heat pipe spreader was performed through an analytical, numerical, and experimental analysis. The physical system considered was comprised of a high heat flux heat source attached...

  15. Resonant absorption in dissipative flux tubes

    E-Print Network [OSTI]

    Safari, H; Karami, K; Sobouti, Y

    2005-01-01T23:59:59.000Z

    Oscillations of coronal loops are believed to be the primary cause of the solar corona heating. We study the resonant absorbtion of MHD waves in magnetized flux tubes with graded densities across the cross section of the tube. Within the approximation that resistive and viscous processes are operative in thin layers surrounding the singularities of the MHD equations, we give the full spectrum of the eigenfrequencies, damping rates, as well as, the eigenfields of the normal MHD modes of the tube. Both surface and body modes are analyzed and the contribution of each class to heating of the corona is commented on.

  16. Atmospheric State, Cloud Microphysics and Radiative Flux

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

    Mace, Gerald

    Atmospheric thermodynamics, cloud properties, radiative fluxes and radiative heating rates for the ARM Southern Great Plains (SGP) site. The data represent a characterization of the physical state of the atmospheric column compiled on a five-minute temporal and 90m vertical grid. Sources for this information include raw measurements, cloud property and radiative retrievals, retrievals and derived variables from other third-party sources, and radiative calculations using the derived quantities.

  17. Physics of Intrinsic Rotation in Flux-Driven ITG Turbulence

    SciTech Connect (OSTI)

    Ku, S; Dimond, P H; Dif-Pradalier, G; Kwon, J M; Sarazin, Y; Hahm, T S; Garbet, X; Chang, C S; Latu, G; Yoon, E S; Ghendrih, Ph; Yi, S; Strugarek, A; Solomon, W

    2012-02-23T23:59:59.000Z

    Global, heat flux-driven ITG gyrokinetic simulations which manifest the formation of macroscopic, mean toroidal flow profiles with peak thermal Mach number 0.05, are reported. Both a particle-in-cell (XGC1p) and a semi-Lagrangian (GYSELA) approach are utilized without a priori assumptions of scale-separation between turbulence and mean fields. Flux-driven ITG simulations with different edge flow boundary conditions show in both approaches the development of net unidirectional intrinsic rotation in the co-current direction. Intrinsic torque is shown to scale approximately linearly with the inverse scale length of the ion temperature gradient. External momentum input is shown to effectively cancel the intrinsic rotation profile, thus confirming the existence of a local residual stress and intrinsic torque. Fluctuation intensity, intrinsic torque and mean flow are demonstrated to develop inwards from the boundary. The measured correlations between residual stress and two fluctuation spectrum symmetry breakers, namely E x B shear and intensity gradient, are similar. Avalanches of (positive) heat flux, which propagate either outwards or inwards, are correlated with avalanches of (negative) parallel momentum flux, so that outward transport of heat and inward transport of parallel momentum are correlated and mediated by avalanches. The probability distribution functions of the outward heat flux and the inward momentum flux show strong structural similarity

  18. Breast cancer screening disparities among ethnically diverse women in California : a latent profile analysis

    E-Print Network [OSTI]

    Gerry, Arianna Aldridge

    2011-01-01T23:59:59.000Z

    minority adolescents: A latent profile analysis. Journal ofKeane, S. P. (2006). Profiles of externalizing behaviorMarch). Developing coping profiles of minority adolescents:

  19. Industrial Heat Recovery - 1982

    E-Print Network [OSTI]

    Csathy, D.

    1982-01-01T23:59:59.000Z

    like: "Vertical, natural circulation boilers are intrinsically mbre reliable than horizontal, forced circula tion boilers.",4 and " it will be seen that horizontal tubes have much lower heat fluxes at burnout than do vertical ones, though...-steam density difference dia gram (Figure 1) has been presented repeat edly in order to indicate a significant density difference between the two phases (even close to the critical pressure) which induces natural circulation. However, this diagra...

  20. Pool boiling heat transfer characteristics of nanofluids

    E-Print Network [OSTI]

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

    2007-01-01T23:59:59.000Z

    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 ...

  1. Determining Reactor Neutrino Flux

    E-Print Network [OSTI]

    Jun Cao

    2012-03-08T23:59:59.000Z

    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.

  2. adult beech trees: Topics by E-print Network

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

    The impact on recharge to the Chalk on shallow soils over chalk in Hampshire. Latent heat flux (evaporation) was calculated as the residual from Boyer, Edmond 159 Review...

  3. NOVEMBER 1997 2847L O F G R E N Simulated Effects of Idealized Laurentian Great Lakes on

    E-Print Network [OSTI]

    cycle of latent and sensible heat flux. Very high upward sensible heat flux occurs over these idealized noted remote effects of the Great Lakes in the form of different precipitation patterns over

  4. Bayesian latent variable modelling in studies of air pollution and health

    E-Print Network [OSTI]

    Burton, Geoffrey R.

    Bayesian latent variable modelling in studies of air pollution and health Duncan Lee, Gavin://www.bath.ac.uk/math-sci/BICS #12;Bayesian latent variable modelling in studies of air pollution and health. Duncan Lee (1), Gavin to air pollution on respiratory mortality in the elderly (aged 65 and above) in London, England, between

  5. A Framework for Incorporating General Domain Knowledge into Latent Dirichlet Allocation using First-Order Logic

    E-Print Network [OSTI]

    Zhu, Xiaojin "Jerry"

    of Latent Dirichlet Allocation (LDA) [Blei et al., 2003], a large number of latent-topic- model variants- rating external knowledge specific to the target domain, see e.g., [Wang et al., 2009; Gerrish and Blei research, too. 2 The Fold·all Framework We now briefly review the standard LDA model [Blei et al., 2003

  6. Clustering Educational Digital Library Usage Data: A Comparison of Latent Class Analysis and

    E-Print Network [OSTI]

    Qi, Xiaojun

    Clustering Educational Digital Library Usage Data: A Comparison of Latent Class Analysis and K-Means Analysis is superior to K-means on all three comparisons. In particular, LCA is more immune to the variance, the widely used K-means and the model-based Latent Class Analysis, are compared, using usage data from

  7. An Investigation of the Latent Semantic Analysis Technique for Document Retrieval

    E-Print Network [OSTI]

    An Investigation of the Latent Semantic Analysis Technique for Document Retrieval STUDENT PROJECT;_________________________________________________________________________ An Investigation of the Latent Semantic Analysis Technique for Document Retrieval. Report by: David Mugo Page 2. These term-matching techniques have always relied on matching query terms with document terms to retrieve

  8. Latent Learning in Deep Neural Nets Steven Gutstein, Olac Fuentes and Eric Freudenthal

    E-Print Network [OSTI]

    Fuentes, Olac

    Latent Learning in Deep Neural Nets Steven Gutstein, Olac Fuentes and Eric Freudenthal Abstract of transfer learning. We utilize latent learning to enable a deep neural net to dis- tinguish among a set-mean' classification technique, which is explained later in this paper. The deep neural net architecture used was a Le

  9. Forced convective heat transfer in channels with internal longitudinal fins

    E-Print Network [OSTI]

    Ong, Liang Eng

    1987-01-01T23:59:59.000Z

    and f in surface temperatures (g ? $b), and the local surface heat flux (q"/Q"). The relative amounts of heat transfer from the exposed channel wall, the surface of the fin along the fin axis, and the fin tip are also calculated individually... heat flux on the tip of the fin. 18 4. RESULTS AND DISCUSSION The results of the computational investigation are presented in this section. They consist of the d istr ibut ions of the d imens ionless temperature (4w ? gb), and the heat flux (q"/Q...

  10. Analysis of radial fin assembly heat transfer with dehumidification

    SciTech Connect (OSTI)

    Rosario, L.; Rahman, M.M. [Univ. of South Florida, Tampa, FL (United States). Dept. of Mechanical Engineering

    1996-12-31T23:59:59.000Z

    The aim of this paper is the analysis of heat transfer in a radial fin assembly during the process of dehumidification. An individual finned tube geometry is a reasonable representation of heat exchangers used in air conditioning. The condensation process involves both heat and mass transfer and the cooling takes place by the removal of sensible as well as latent heat. The ratio of sensible to total heat is an important quantity that defines the heat transfer process during a dehumidifier operation. A one-dimensional model for heat transfer in the fin and the heat exchanger block is developed to study the effects of condensation on the fin surface. The combined heat and mass transfer process is modeled by incorporating the ratio of sensible to total heat in the formulation. The augmentation of heat transfer due to fin was established by comparing heat transfer rate with and without fins under the same operating conditions. Numerical calculations were carried out to study the effects of relative humidity and dry bulb temperature of the incoming air, and cold fluid temperature inside the coil on the performance of the heat exchanger. Results were compared to those published for rectangular fin under humid condition showed excellent agreement when the present model was used to compute that limiting condition. It was found that the heat transfer rate increased with increment in both dry bulb temperature and relative humidity of the air. The augmentation factor, however, decreased with increment in relative humidity and the dry bulb temperature.

  11. Heat transfer in katabatic flow Measurements on the Morteratsch glacier, Switzerland

    E-Print Network [OSTI]

    Graaf, Martin de

    Heat transfer in katabatic flow Measurements on the Morteratsch glacier, Switzerland M. de Graaf #12;Heat transfer in katabatic flow Measurements on the Morteratsch glacier, Switzerland Martin de is used to calculate surface heat fluxes over glaciers. As determination of surface fluxes still

  12. Radiative Flux Analysis

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

    Long, Chuck [NOAA

    The Radiative Flux Analysis is a technique for using surface broadband radiation measurements for detecting periods of clear (i.e. cloudless) skies, and using the detected clear-sky data to fit functions which are then used to produce continuous clear-sky estimates. The clear-sky estimates and measurements are then used in various ways to infer cloud macrophysical properties.

  13. Urban Energy Fluxes in Built-Up Downtown Areas and Variations across the Urban Area, for Use in Dispersion Models

    E-Print Network [OSTI]

    Hanna, Steven

    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 ...

  14. On the Effect of Porous Layers on Melting Heat Transfer in an Enclosure

    E-Print Network [OSTI]

    Beckermann, Christoph

    : melting, porous media, thermal energy storage, natural convection INTRODUCTION Latent heat thermal energy-change materials used in such thermal energy storage devices have a relatively low thermal conductivity, means investigated in detail. The presence of the porous medium can considerably reduce the thermal energy storage

  15. Formation of nanometer-size wires using infiltration into latent nuclear tracks

    DOE Patents [OSTI]

    Musket, Ronald G. (Danville, CA); Felter, Thomas E. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    Nanometer-size wires having a cross-sectional dimension of less than 8 nm with controllable lengths and diameters are produced by infiltrating latent nuclear or ion tracks formed in trackable materials with atomic species. The trackable materials and atomic species are essentially insoluble in each other, thus the wires are formed by thermally driven, self-assembly of the atomic species during annealing, or re-crystallization, of the damage in the latent tracks. Unlike conventional ion track lithography, the inventive method does not require etching of the latent tracks.

  16. Susanville District Heating District Heating Low Temperature...

    Open Energy Info (EERE)

    Susanville District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Susanville District Heating District Heating Low Temperature...

  17. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 1,602 1,397...

  18. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Energy Consumption Survey: Energy End-Use Consumption Tables Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All...

  19. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 1,870 1,276...

  20. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings ... 2,037...

  1. Mixed Layer Lateral Eddy Fluxes Mediated by Air-Sea Interaction

    E-Print Network [OSTI]

    Shuckburgh, Emily

    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 ...

  2. Stabilization of moduli by fluxes

    SciTech Connect (OSTI)

    Behrndt, Klaus [Albert-Einstein-Institute, Am Muehlenberg 1, 14476 Golm (Germany)

    2004-12-10T23:59:59.000Z

    In order to fix the moduli, non-trivial fluxes might the essential input. We summarize different aspects of compactifications in the presence of fluxes, as there is the relation to generalized Scherk-Schwarz reductions and gauged supergravity but also the description of flux-deformed geometries in terms of G-structures and intrinsic torsion.

  3. Polarity Inducing Latent Semantic Analysis Wen-tau Yih Geoffrey Zweig John C. Platt

    E-Print Network [OSTI]

    Hunt, Galen

    Polarity Inducing Latent Semantic Analysis Wen-tau Yih Geoffrey Zweig John C. Platt Microsoft) and cross-lingual docu- ment retrieval (Platt et al., 2010). At the word level, vector representations have

  4. A Latent Mixed Membership Model for Relational Data Edoardo Airoldi, David Blei, Eric Xing

    E-Print Network [OSTI]

    Murphy, Robert F.

    A Latent Mixed Membership Model for Relational Data Edoardo Airoldi, David Blei, Eric Xing School of Computer Science Carnegie Mellon University {eairoldi,blei,xing}@cs.cmu.edu Stephen Fienberg Department

  5. A study of the minimum meniscus radius as a function of vapor temperature using heat pipes

    E-Print Network [OSTI]

    Sonnier, Ronald James

    1973-01-01T23:59:59.000Z

    /sec 2 latent heat of vaporization, BTU/lb m wick permeability, ft 2 length, ft molecular weight, ibm water parameter, hf pfof/uf fgff f pressure, lbf/ft 2 desorption pressure, lbf/ft 2 saturation pressure, lbf/ft 2 heat transfer rate, BTU... into Cosgrove's equation, assuming the temperature is uni- form inside the heat pipe, replacing the sum of the section lengths by the total length of the heat pipe, and combining the fluid prop- erties into one var1able there is obtained N = hf pfof/uf...

  6. Heating system

    SciTech Connect (OSTI)

    Nishman, P.J.

    1983-03-08T23:59:59.000Z

    A heating system utilizing solar panels and buried ground conduits to collect and store heat which is delivered to a heatpump heat exchanger. A heat-distribution fluid continuously circulates through a ground circuit to transfer heat from the ground to the heat exchanger. The ground circuit includes a length of buried ground conduit, a pump, a check valve and the heat exchanger. A solar circuit, including a solar panel and a second pump, is connected in parallel with the check valve so that the distribution fluid transfers solar heat to the heat exchanger for utilization and to the ground conduit for storage when the second pump is energized. A thermostatically instrumented control system energizes the second pump only when the temperature differential between the solar panel inlet and outlet temperatures exceeds a predetermined value and the ground temperature is less than a predetermined value. Consequently, the distribution fluid flows through the solar panel only when the panel is capable of supplying significant heat to the remainder of the system without causing excessive drying of the ground.

  7. Traveling-wave device with mass flux suppression

    DOE Patents [OSTI]

    Swift, Gregory W. (Santa Fe, NM); Backhaus, Scott N. (Los Alamos, NM); Gardner, David L. (White Rock, NM)

    2000-01-01T23:59:59.000Z

    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.

  8. Enhancing multilingual latent semantic analysis with term alignment information.

    SciTech Connect (OSTI)

    Chew, Peter A.; Bader, Brett William

    2008-08-01T23:59:59.000Z

    Latent Semantic Analysis (LSA) is based on the Singular Value Decomposition (SVD) of a term-by-document matrix for identifying relationships among terms and documents from co-occurrence patterns. Among the multiple ways of computing the SVD of a rectangular matrix X, one approach is to compute the eigenvalue decomposition (EVD) of a square 2 x 2 composite matrix consisting of four blocks with X and XT in the off-diagonal blocks and zero matrices in the diagonal blocks. We point out that significant value can be added to LSA by filling in some of the values in the diagonal blocks (corresponding to explicit term-to-term or document-to-document associations) and computing a term-by-concept matrix from the EVD. For the case of multilingual LSA, we incorporate information on cross-language term alignments of the same sort used in Statistical Machine Translation (SMT). Since all elements of the proposed EVD-based approach can rely entirely on lexical statistics, hardly any price is paid for the improved empirical results. In particular, the approach, like LSA or SMT, can still be generalized to virtually any language(s); computation of the EVD takes similar resources to that of the SVD since all the blocks are sparse; and the results of EVD are just as economical as those of SVD.

  9. Micro- and Nanoscale Measurement Methods for Phase Change Heat Transfer on Planar and Structured Surfaces

    E-Print Network [OSTI]

    Buongiorno, Jacopo

    In this opinion piece, we discuss recent advances in experimental methods for characterizing phase change heat transfer. We begin with a survey of techniques for high-resolution measurements of temperature and heat flux ...

  10. Heat Transfer -1 A satellite in space orbits the sun. The satellite can be approximated as a flat plate with

    E-Print Network [OSTI]

    Virginia Tech

    Heat Transfer - 1 A satellite in space orbits the sun. The satellite can be approximated as a flat plate with dimensions and properties given below. (a) Calculate the solar heat flux (W/m2 is at a distance where the solar heat flux (as defined above) is 500 W/m2 , and the flat plate is oriented

  11. Sandia National Laboratories: Beryllium High Heat Flux Testing...

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

    system, controls, and blast gun) is now used for electron beam test system vacuum vessel beryllium decontamination and has shortened the beryllium clean-up procedure from...

  12. Systematic errors in ground heat flux estimation and their correction

    E-Print Network [OSTI]

    Gentine, P.

    Incoming radiation forcing at the land surface is partitioned among the components of the surface energy balance in varying proportions depending on the time scale of the forcing. Based on a land-atmosphere analytic continuum ...

  13. Lyapunov Modes for a Nonequilibrium System with a Heat Flux

    E-Print Network [OSTI]

    Tooru Taniguchi; Gary P. Morriss

    2006-11-23T23:59:59.000Z

    We present the first numerical observation of Lyapunov modes (mode structure of Lyapunov vectors) in a system maintained in a nonequilibrium steady state. The modes show some similarities and some differences when compared with the results for equilibrium systems. The breaking of energy conservation removes a zero exponent and introduces a new mode. The transverse modes are only weakly altered but there are systematic changes to the longitudinal and momentum dependent modes.

  14. Technical Sessions Measurements of Surface Heat Flux Over Contrasting Surfaces

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructureProposedPAGESafety Tag:8,, 20153 To.T. J. Kulp

  15. High Heat Flux Thermoelectric Module Using Standard Bulk Material |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(Fact Sheet), GeothermalGridHYDROGEN TOTechnologyHigh Efficiency LowDepartment of

  16. Sensitivity of Radiative Fluxes and Heating Rates to Cloud Microphysics

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz is TakingDepartmentSensitivities of SCMs

  17. Effect on Non-Uniform Heat Generation on Thermionic Reactions

    SciTech Connect (OSTI)

    Schock, Alfred

    2012-01-19T23:59:59.000Z

    The penalty resulting from non-uniform heat generation in a thermionic reactor is examined. Operation at sub-optimum cesium pressure is shown to reduce this penalty, but at the risk of a condition analogous to burnout. For high pressure diodes, a simple empirical correlation between current, voltage and heat flux is developed and used to analyze the performance penalty associated with two different heat flux profiles, for series-and parallel-connected converters. The results demonstrate that series-connected converters require much finer power flattening than parallel converters. For example, a ±10% variation in heat generation across a series array can result in a 25 to 50% power penalty.

  18. NUMERICAL SIMULATION OF POOL BOILING FOR STEADY STATE AND TRANSIENT HEATING

    E-Print Network [OSTI]

    Maruyama, Shigeo

    1 NUMERICAL SIMULATION OF POOL BOILING FOR STEADY STATE AND TRANSIENT HEATING Ying He, Masahiro role in nucleate and transition boiling heat transfer at high heat flux. Many experiments have been in the numerical simulation of boiling heat transfer. In this study, based on the macrolayer evaporation model

  19. Inverse estimation of surface heating condition in a three-dimensional object using conjugate gradient method

    E-Print Network [OSTI]

    Zhang, Yuwen

    heat conduction Laser Gaussian profile Conjugate gradient method a b s t r a c t Temperature and heat gradient method Jianhua Zhou, Yuwen Zhang *, J.K. Chen, Z.C. Feng Department of Mechanical and Aerospace gradient method (CGM) with temperature and heat flux measured on back surface (opposite to the heated

  20. Heat Transfer to the Structure during the Fire 

    E-Print Network [OSTI]

    Jowsey, Allan; Torero, Jose L; Lane, Barbara

    2007-11-14T23:59:59.000Z

    The post-flashover Fire Test One of a furnished room in Dalmarnock provides a wealth of information including measurements in both the gas phase and on compartment boundaries (Chapter 3). Total heat fluxes at a number ...

  1. Influence of Infrared Radiation on Attic Heat Transfer 

    E-Print Network [OSTI]

    Katipamula, S.; Turner, W. D.; Murphy, W. E.; O'Neal, D. L.

    1985-01-01T23:59:59.000Z

    roof temperatures. It was found that a radiant barrier such as aluminum foil can reduce the heat flux significantly. Experimental results were compared to a Three-Region approximate solution developed at Oak Ridge National Laboratories (ORNL). The model...

  2. Physics of String Flux Compactifications

    E-Print Network [OSTI]

    Frederik Denef; Michael R. Douglas; Shamit Kachru

    2007-01-06T23:59:59.000Z

    We provide a qualitative review of flux compactifications of string theory, focusing on broad physical implications and statistical methods of analysis.

  3. Fluxes, Gaugings and Gaugino Condensates

    E-Print Network [OSTI]

    J. -P. Derendinger; C. Kounnas; P. M. Petropoulos

    2006-02-10T23:59:59.000Z

    Based on the correspondence between the N = 1 superstring compactifications with fluxes and the N = 4 gauged supergravities, we study effective N = 1 four-dimensional supergravity potentials arising from fluxes and gaugino condensates in the framework of orbifold limits of (generalized) Calabi-Yau compactifications. We give examples in heterotic and type II orientifolds in which combined fluxes and condensates lead to vacua with small supersymmetry breaking scale. We clarify the respective roles of fluxes and condensates in supersymmetry breaking, and analyze the scaling properties of the gravitino mass.

  4. Materials Compatibility and Aging for Flux and Cleaner Combinations.

    SciTech Connect (OSTI)

    Archuleta, Kim; Piatt, Rochelle

    2015-01-01T23:59:59.000Z

    A materials study of high reliability electronics cleaning is presented here. In Phase 1, mixed type substrates underwent a condensed contaminants application to view a worst- case scenario for unremoved flux with cleaning agent residue for parts in a silicone oil filled environment. In Phase 2, fluxes applied to copper coupons and to printed wiring boards underwent gentle cleaning then accelerated aging in air at 65% humidity and 30 O C. Both sets were aged for 4 weeks. Contaminants were no-clean (ORL0), water soluble (ORH1 liquid and ORH0 paste), and rosin (RMA; ROL0) fluxes. Defluxing agents were water, solvents, and engineered aqueous defluxers. In the first phase, coupons had flux applied and heated, then were placed in vials of oil with a small amount of cleaning agent and additional coupons. In the second phase, pairs of copper coupons and PWB were hand soldered by application of each flux, using tin-lead solder in a strip across the coupon or a set of test components on the PWB. One of each pair was cleaned in each cleaning agent, the first with a typical clean, and the second with a brief clean. Ionic contamination residue was measured before accelerated aging. After aging, substrates were removed and a visual record of coupon damage made, from which a subjective rank was applied for comparison between the various flux and defluxer combinations; more corrosion equated to higher rank. The ORH1 water soluble flux resulted in the highest ranking in both phases, the RMA flux the least. For the first phase, in which flux and defluxer remained on coupons, the aqueous defluxers led to worse corrosion. The vapor phase cleaning agents resulted in the highest ranking in the second phase, in which there was no physical cleaning. Further study of cleaning and rinsing parameters will be required.

  5. Effects of Radiative Diffusion on Thin Flux Tubes in Turbulent Solar-like Convection

    E-Print Network [OSTI]

    Weber, Maria A

    2015-01-01T23:59:59.000Z

    We study the combined effects of convection and radiative diffusion on the evolution of thin magnetic flux tubes in the solar interior. Radiative diffusion is the primary supplier of heat to convective motions in the lower convection zone, and it results in a heat input per unit volume of magnetic flux tubes that has been ignored by many previous thin flux tube studies. We use a thin flux tube model subject to convection taken from a rotating spherical shell of turbulent, solar-like convection as described by Weber, Fan, and Miesch (2011, Astrophys. J., 741, 11; 2013, Solar Phys., 287, 239), now taking into account the influence of radiative heating on flux tubes of large-scale active regions. Our simulations show that flux tubes of less than or equal to 60 kG subject to solar-like convective flows do not anchor in the overshoot region, but rather drift upward due to the increased buoyancy of the flux tube earlier in its evolution as a result of the inclusion of radiative diffusion. Flux tubes of magnetic fie...

  6. Corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, Scott L. (Annandale, VA)

    1989-01-01T23:59:59.000Z

    A corrosive and errosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is conveyed through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium.

  7. 1194 VOLUME 10J O U R N A L O F C L I M A T E 1997 American Meteorological Society

    E-Print Network [OSTI]

    Xue, Yongkang

    fluxes, and also comparing them with latent heat fluxes derived from a surface energy balance. Tuning and Applications Incorporated, New York City, New York f Mesoscale Dynamics and Precipitation Branch, NASA

  8. Heat collector

    DOE Patents [OSTI]

    Merrigan, Michael A. (Santa Cruz, NM)

    1984-01-01T23:59:59.000Z

    A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

  9. Heat collector

    DOE Patents [OSTI]

    Merrigan, M.A.

    1981-06-29T23:59:59.000Z

    A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

  10. Eddy fluxes in baroclinic turbulence

    E-Print Network [OSTI]

    Thompson, Andrew F.

    2006-01-01T23:59:59.000Z

    Gill 1982), which transport warm (cold) ?uid poleward (heat transport. Panel (a) shows how warm and cold patches

  11. Development of an Air-Source Heat Pump Integrated with a Water Heating / Dehumidification Module

    SciTech Connect (OSTI)

    Rice, C Keith [ORNL] [ORNL; Uselton, Robert B. [Lennox Industries, Inc] [Lennox Industries, Inc; Shen, Bo [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Shrestha, Som S [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    A residential-sized dual air-source integrated heat pump (AS-IHP) concept is under development in partnership between ORNL and a manufacturer. The concept design consists of a two-stage air-source heat pump (ASHP) coupled on the air distribution side with a separate novel water heating/dehumidification (WH/DH) module. The motivation for this unusual equipment combination is the forecast trend for home sensible loads to be reduced more than latent loads. Integration of water heating with a space dehumidification cycle addresses humidity control while performing double-duty. This approach can be applied to retrofit/upgrade applications as well as new construction. A WH/DH module capable of ~1.47 L/h water removal and ~2 kW water heating capacity was assembled by the manufacturer. A heat pump system model was used to guide the controls design; lab testing was conducted and used to calibrate the models. Performance maps were generated and used in a TRNSYS sub-hourly simulation to predict annual performance in a well-insulated house. Annual HVAC/WH energy savings of ~35% are predicted in cold and hot-humid U.S. climates compared to a minimum efficiency baseline.

  12. Analytical modeling for the heat transfer in sheared flows of nanofluids

    E-Print Network [OSTI]

    Ferrari, Claudio; L'vov, Victor S; Procaccia, Itamar; Rudenko, Oleksii; Boonkkamp, J H M ten Thije; Toschi, Federico

    2012-01-01T23:59:59.000Z

    We developed a model for the enhancement of the heat flux by spherical and elongated nano- particles in sheared laminar flows of nano-fluids. Besides the heat flux carried by the nanoparticles the model accounts for the contribution of their rotation to the heat flux inside and outside the particles. The rotation of the nanoparticles has a twofold effect, it induces a fluid advection around the particle and it strongly influences the statistical distribution of particle orientations. These dynamical effects, which were not included in existing thermal models, are responsible for changing the thermal properties of flowing fluids as compared to quiescent fluids. The proposed model is strongly supported by extensive numerical simulations, demonstrating a potential increase of the heat flux far beyond the Maxwell-Garnet limit for the spherical nanoparticles. The road ahead which should lead towards robust predictive models of heat flux enhancement is discussed.

  13. Analytical modeling for the heat transfer in sheared flows of nanofluids

    E-Print Network [OSTI]

    Claudio Ferrari; Badr Kaoui; Victor S. L'vov; Itamar Procaccia; Oleksii Rudenko; J. H. M. ten Thije Boonkkamp; Federico Toschi

    2012-04-12T23:59:59.000Z

    We developed a model for the enhancement of the heat flux by spherical and elongated nano- particles in sheared laminar flows of nano-fluids. Besides the heat flux carried by the nanoparticles the model accounts for the contribution of their rotation to the heat flux inside and outside the particles. The rotation of the nanoparticles has a twofold effect, it induces a fluid advection around the particle and it strongly influences the statistical distribution of particle orientations. These dynamical effects, which were not included in existing thermal models, are responsible for changing the thermal properties of flowing fluids as compared to quiescent fluids. The proposed model is strongly supported by extensive numerical simulations, demonstrating a potential increase of the heat flux far beyond the Maxwell-Garnet limit for the spherical nanoparticles. The road ahead which should lead towards robust predictive models of heat flux enhancement is discussed.

  14. Acoustically Enhanced Boiling Heat Transfer

    E-Print Network [OSTI]

    Z. W. Douglas; M. K. Smith; A. Glezer

    2008-01-07T23:59:59.000Z

    An acoustic field is used to increase the critical heat flux (CHF) of a flat-boiling-heat-transfer surface. The increase is a result of the acoustic effects on the vapor bubbles. Experiments are performed to explore the effects of an acoustic field on vapor bubbles in the vicinity of a rigid-heated wall. Work includes the construction of a novel heater used to produce a single vapor bubble of a prescribed size and at a prescribed location on a flatboiling surface for better study of an individual vapor bubble's reaction to the acoustic field. Work also includes application of the results from the single-bubble heater to a calibrated-copper heater used for quantifying the improvements in CHF.

  15. Heating 7. 2 user's manual

    SciTech Connect (OSTI)

    Childs, K.W.

    1993-02-01T23:59:59.000Z

    HEATING is a general-purpose conduction heat transfer program written in Fortran 77. HEATING can solve steady-state and/or transient heat conduction problems in one-, two-, or three-dimensional Cartesian, cylindrical, or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time- and temperature-dependent. The thermal conductivity may also be anisotropic. Materials may undergo change of phase. Thermal properties of materials may be input or may be extracted from a material properties library. Heat-generation rates may be dependent on time, temperature, and position, and boundary temperatures may be time- and position-dependent. The boundary conditions, which may be surface-to-environment or surface-to-surface, may be specified temperatures or any combination of prescribed heat flux, forced convection, natural convection, and radiation. The boundary condition parameters may be time- and/or temperature-dependent. General gray-body radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING uses a runtime memory allocation scheme to avoid having to recompile to match memory requirements for each specific problem. HEATING utilizes free-form input. Three steady-state solution techniques are available: point-successive-overrelaxation iterative method with extrapolation, direct-solution, and conjugate gradient. Transient problems may be solved using any one of several finite-difference schemes: Crank-Nicolson implicit, Classical Implicit Procedure (CIP), Classical Explicit Procedure (CEP), or Levy explicit method. The solution of the system of equations arising from the implicit techniques is accomplished by point-successive-overrelaxation iteration and includes procedures to estimate the optimum acceleration parameter.

  16. AOSC 621AOSC 621 Radiative Heating/CoolingRadiative Heating/Cooling

    E-Print Network [OSTI]

    Li, Zhanqing

    ? Why drop off near sfc? 4 #12;Net flux Net flux: F = F+ - F- 1 2 F-(1) F+(1) F-(2) F+(2) Net energy at the top of the atmosphere is zero. Then we can write 1' ' )',( )'()0,()( 0 * dz dz zzdT zBzTBzF z z F F · The heating rate at z is defined as follows: )( )( d zdF zH net four termsofconsistwilland dz A

  17. Heating System Specification Specification of Heating System

    E-Print Network [OSTI]

    Day, Nancy

    Appendix A Heating System Specification /* Specification of Heating System (loosely based */ requestHeat : Room ­? bool; 306 #12; APPENDIX A. HEATING SYSTEM SPECIFICATION 307 /* user inputs */ livingPattern : Room ­? behaviour; setTemp : Room ­? num; heatSwitchOn, heatSwitchOff, userReset : simple

  18. Comments on article 'symmetric heat and mass transfer in a rotating spherical layer,' JETP 94 (3), 459 (2002)

    SciTech Connect (OSTI)

    Alexandrov, D. V., E-mail: Dmitri.Alexandrov@usu.ru; Malygin, A. P. [Ural Federal University (Russian Federation)

    2012-02-15T23:59:59.000Z

    Analytic solutions to the heat and mass transfer equations, which were obtained in [1], are corrected. It is shown that the dependence of the growth rate of the Earth's inner core on heat flux changes in this case.

  19. PMEL Ocean Climate Station Program Meghan Cronin, Chris Sabine, Chris Meinig

    E-Print Network [OSTI]

    . Papa HOT MBARI Cold dry air blowing over warm Kuroshio Extension causes large sensible and latent heat for climate reference) Net Surface Heat Flux = TurbPMEL Ocean Climate Station Program Meghan Cronin, Chris Sabine, Chris Meinig NOAA Pacific Marine

  20. Heat Exchanger Fouling- Prediction, Measurement and Mitigation

    E-Print Network [OSTI]

    Peterson, G. R.

    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...

  1. Microwave Tokamak Experiment (MTX) ohmic heating system

    SciTech Connect (OSTI)

    Jackson, M.C. (Lawrence Livermore National Lab., CA (USA))

    1989-09-13T23:59:59.000Z

    The ohmic heating system for the Microwave Tokamak Experiment (MTX) at Lawrence Livermore National Laboratory (LLNL) provides both the voltage for the initial breakdown phase and the energy to drive the plasma current to a value of 400 kA or greater. Providing this voltage and flux swing requires a one-turn loop voltage of about 25 volts (11 kV across the coil) and a magnetic flux swing of 2 volt- seconds. This voltage and flux swing are accomplished by charging the ohmic heating coils to 20 kA, at which point the current is commutated off into a resistor generating the 11 kV across the coil. When the current passes through zero, another power supply drives the current in the opposite polarity to 20 kA, thus completing the full 2 volt-second flux swing. This paper describes the design features and performance of the ohmic heating circuit, with emphasis on the commutation circuit. In addition, the paper describes the use of the ohmic heating system for discharge cleaning and the changeover procedure. 3 refs., 4 figs., 1 tab.

  2. Radiative component and combined heat transfer in the thermal calculation of finned tube banks

    SciTech Connect (OSTI)

    Stehlik, P. [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering] [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering

    1999-01-01T23:59:59.000Z

    For more exact calculation of combined heat transfer in the case of finned tube banks (e.g., in the convective section of a furnace), the radiative heat transfer cannot be neglected. A new method for relatively simple calculation of total heat flux (convection + radiation + conduction in fins) is fully compatible with that for bare tube banks/bundles developed earlier. It is based on the method of radiative coefficients. However, the resulting value of heat flux must be corrected due to fin thickness and especially due to the fin radiative influence. For this purpose the so-called multiplicator of heat flux was introduced. The applicability of this methods has been demonstrated on a tubular fired heater convective section. A developed computer program based on the method has also been used for an analysis of the influence of selected parameters to show the share of radiation on the total heat flux.

  3. The budgets of heat and salinity in NEMO M. Hieronymus

    E-Print Network [OSTI]

    Nycander, Jonas

    of the ocean is seen to be dominated by penetrative shortwave radiation, which is so influ- ential that we Keywords: Heat budget Salinity budget NEMO Isoneutral diffusion Shortwave penetration a b s t r a c in the Nucleus for European Modelling of the Ocean (NEMO) model. It is seen that the heat fluxes in NEMO

  4. The Solar Wind Energy Flux

    E-Print Network [OSTI]

    Chat, G Le; Meyer-Vernet, N

    2012-01-01T23:59:59.000Z

    The solar-wind energy flux measured near the ecliptic is known to be independent of the solar-wind speed. Using plasma data from Helios, Ulysses, and Wind covering a large range of latitudes and time, we show that the solar-wind energy flux is independent of the solar-wind speed and latitude within 10%, and that this quantity varies weakly over the solar cycle. In other words the energy flux appears as a global solar constant. We also show that the very high speed solar-wind (VSW > 700 km/s) has the same mean energy flux as the slower wind (VSW < 700 km/s), but with a different histogram. We use this result to deduce a relation between the solar-wind speed and density, which formalizes the anti-correlation between these quantities.

  5. Triaxial thermopile array geo-heat-flow sensor

    DOE Patents [OSTI]

    Carrigan, C.R.; Hardee, H.C.; Reynolds, G.D.; Steinfort, T.D.

    1990-01-01T23:59:59.000Z

    A triaxial thermopile array geothermal heat flow sensor is designed to measure heat flow in three dimensions in a reconstituted or unperturbed subsurface regime. Heat flow can be measured in conductive or permeable convective media. The sensor may be encased in protective pvc tubing and includes a plurality of thermistors and an array of heat flow transducers produce voltage proportional to heat flux along the subsurface regime and permit direct measurement of heat flow in the subsurface regime. The presence of the thermistor array permits a comparison to be made between the heat flow estimates obtained from the transducers and heat flow calculated using temperature differences and Fourier's Law. The device is extremely sensitive with an accuracy of less than 0.1 Heat Flow Units (HFU) and may be used for long term readings. 6 figs.

  6. Triaxial thermopile array geo-heat-flow sensor

    DOE Patents [OSTI]

    Carrigan, Charles R. (Tracy, CA); Hardee, Harry C. (Albuquerque, NM); Reynolds, Gerald D. (Tijeras, NM); Steinfort, Terry D. (Tijeras, NM)

    1992-01-01T23:59:59.000Z

    A triaxial thermopile array geothermal heat flow sensor is designed to measure heat flow in three dimensions in a reconstituted or unperturbed subsurface regime. Heat flow can be measured in conductive or permeable convective media. The sensor may be encased in protective pvc tubing and includes a plurality of thermistors and an array of heat flow transducers arranged in a vertical string. The transducers produce voltage proportional to heat flux along the subsurface regime and permit direct measurement of heat flow in the subsurface regime. The presence of the thermistor array permits a comparison to be made between the heat flow estimates obtained from the transducers and heat flow calculated using temperature differences and Fourier's Law. The device is extremely sensitive with an accuracy of less than 0.1 Heat Flow Units (HFU) and may be used for long term readings.

  7. Rapid Communication Herpes simplex virus 1 microRNAs expressed abundantly during latent infection are

    E-Print Network [OSTI]

    Knipe, David M.

    Rapid Communication Herpes simplex virus 1 microRNAs expressed abundantly during latent infection Available online 23 July 2011 Keywords: Herpes simplex virus MicroRNAs Latency Gene regulation Several herpes simplex virus 1 microRNAs are encoded within or near the latency associated transcript (LAT) locus

  8. Condensation Risk in a Room with High Latent Load and Chilled Ceiling

    E-Print Network [OSTI]

    Chen, Qingyan "Yan"

    proposed a new ventilation system with radiant cooling panel and air supplied from a liquid desiccant dehumidification system, which provided very dry supply air and chilled water for radiant cooling. This study usedCondensation Risk in a Room with High Latent Load and Chilled Ceiling Panel and with Air Supplied

  9. Latent Gaussian Models for Topic Modeling Changwei Hu Eunsu Ryu David Carlson Yingjian Wang Lawrence Carin

    E-Print Network [OSTI]

    Kaski, Samuel

    of legislation (Gerrish & Blei, 2011; Zhang & Carin, 2012), where the text of the legislation is in terms of p1. Typically it is assumed that Xij 0 for all (i, j). In latent Dirichlet allocation (LDA) (Blei et al., 2003 developed topic models, like the nested Chinese restaurant process (nCRP)(Blei et al., 2010; Wang & Blei

  10. Paternal age related schizophrenia (PARS): latent subgroups detected by k-means clustering analysis

    E-Print Network [OSTI]

    Ahn, Hongshik

    1 Paternal age related schizophrenia (PARS): latent subgroups detected by k-means clustering of schizophrenia with distinct etiology, pathophysiology and symptoms. This study uses a k-means clustering-R) and olfaction (University of Pennsylvania Smell Identification Test; UPSIT). We conducted a series of k-means

  11. Efficient Energy Management and Data Recovery in Sensor Networks using Latent Variables Based Tensor

    E-Print Network [OSTI]

    Simunic, Tajana

    Efficient Energy Management and Data Recovery in Sensor Networks using Latent Variables Based factor in a successful sensor network deployment is finding a good balance between maximizing the number of measurements taken (to maintain a good sampling rate) and minimizing the overall energy consumption (to extend

  12. Segmentation and Enhancement of Latent Fingerprints: A Coarse to Fine Ridge

    E-Print Network [OSTI]

    ., "Image Quality Assessment: From Error Visibility to Structural Similarity", IEEE Transaction on ImageSegmentation and Enhancement of Latent Fingerprints: A Coarse to Fine Ridge Structure Dictionary ridge Pores · Include all dimensional attributes of the ridge such as pores, edge contour, incipient

  13. Tuberculosis and Latent TB Treatment Approved by the UHS Patient Education Committee

    E-Print Network [OSTI]

    Yener, Aylin

    health care Who abuse drugs and/or alcohol Who work or are residents of long-term care facilities return to the health care worker who will check to see if there is a reaction to the test. A positive tell the health care worker prior to having the test repeated. #12;Tuberculosis and Latent TB Treatment

  14. Latent Friend Mining from Blog Data , Jian-Tao Sun2

    E-Print Network [OSTI]

    Yang, Qiang

    , it is not easy to obtain and maintain the profiles manually. Therefore, the automatic approaches in mining usersLatent Friend Mining from Blog Data Dou Shen1 , Jian-Tao Sun2 , Qiang Yang1 , Zheng Chen2 1 in recent years with benefits for different types of users. For individuals, the Web community helps

  15. Simplified Numerical Description of Latent Storage Characteristics for Phase Change Wallboard

    E-Print Network [OSTI]

    Fuestel, H.E.

    2011-01-01T23:59:59.000Z

    of Phase Change Technology for Heating and Cooling oftechnology integrated into the building structure as thermal storage for heating and

  16. Berry-Phase-Induced Heat Pumping and Its Impact on the Fluctuation Theorem Jie Ren (),1,2,* Peter Hanggi,2,3,

    E-Print Network [OSTI]

    Li, Baowen

    Berry-Phase-Induced Heat Pumping and Its Impact on the Fluctuation Theorem Jie Ren (),1,2,* Peter heat baths. We demonstrate that the pumped heat typically exhibits a Berry-phase effect in providing-dependent manipulations various molecular heat pumps have been proposed to efficiently control heat flux against thermal

  17. A climatic heat budget study of the Gulf of Mexico

    E-Print Network [OSTI]

    Etter, Paul Courtney

    1975-01-01T23:59:59.000Z

    of heat storage (G ) is calo~ lated apparently for the first time directly by use of available bathythermograph (BT) data. Heat flux di rergence due to currents (0 ), calculated as a residual in the heat budget equation, is small. The monthly mean... surface ( CA) . . 16 C. The rate of heat storage (Q ) 32 0. Solution of the oceanic heat budget 39 Comparison with Earlier Studies Summary 56 References Appendix A App ndix 3 Vita 61 79 vi LIST OF TA. '3LES Table Page Number of observations...

  18. Computation of radiative heat transport across a nanoscale vacuum gap

    SciTech Connect (OSTI)

    Budaev, Bair V., E-mail: bair@berkeley.edu; Bogy, David B., E-mail: dbogy@berkeley.edu [University of California, Etcheverry Hall, MC 1740, Berkeley, California 94720-1740 (United States)

    2014-02-10T23:59:59.000Z

    Radiation heat transport across a vacuum gap between two half-spaces is studied. By consistently applying only the fundamental laws of physics, we obtain an algebraic equation that connects the temperatures of the half-spaces and the heat flux between them. The heat transport coefficient generated by this equation for such structures matches available experimental data for nanoscale and larger gaps without appealing to any additional specific mechanisms of energy transfer.

  19. Finite ballooning angle effects on ion temperature gradient driven mode in gyrokinetic flux tube simulations

    SciTech Connect (OSTI)

    Singh, Rameswar, E-mail: rameswar.singh@lpp.polytechnique.fr [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India) [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India); Laboratoire de Physique des Plasmas, Ecole Polytechnique, Route de Saclay, 91128 Palaiseau Cedex (France); Brunner, S. [CRPP, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland)] [CRPP, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland); Ganesh, R. [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India)] [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India); Jenko, F. [Max-Planck-Institut fur Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)] [Max-Planck-Institut fur Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)

    2014-03-15T23:59:59.000Z

    This paper presents effects of finite ballooning angles on linear ion temperature gradient (ITG) driven mode and associated heat and momentum flux in Gyrokinetic flux tube simulation GENE. It is found that zero ballooning angle is not always the one at which the linear growth rate is maximum. The ITG mode acquires a short wavelength (SW) branch (k{sub ?}?{sub i}?>?1) when growth rates maximized over all ballooning angles are considered. However, the SW branch disappears on reducing temperature gradient showing characteristics of zero ballooning angle SWITG in case of extremely high temperature gradient. Associated heat flux is even with respect to ballooning angle and maximizes at nonzero ballooning angle while the parallel momentum flux is odd with respect to the ballooning angle.

  20. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F. (Cleveland, OH); Moore, Paul B. (Fedhaurn, FL)

    1982-01-01T23:59:59.000Z

    An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchanges and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

  1. Thermality of the Hawking flux

    E-Print Network [OSTI]

    Matt Visser

    2015-02-09T23:59:59.000Z

    Is the Hawking flux "thermal"? Unfortunately, the answer to this seemingly innocent question depends on a number of often unstated, but quite crucial, technical assumptions built into modern (mis-)interpretations of the word "thermal". The original 1850's notions of thermality --- based on classical thermodynamic reasoning applied to idealized "black bodies" or "lamp black surfaces" --- when supplemented by specific basic quantum ideas from the early 1900's, immediately led to the notion of the black-body spectrum, (the Planck-shaped spectrum), but "without" any specific assumptions or conclusions regarding correlations between the quanta. Many (not all) modern authors (often implicitly and unintentionally) add an extra, and quite unnecessary, assumption that there are no correlations in the black-body radiation; but such usage is profoundly ahistorical and dangerously misleading. Specifically, the Hawking flux from an evaporating black hole, (just like the radiation flux from a leaky furnace or a burning lump of coal), is only "approximately" Planck-shaped over a bounded frequency range. Standard physics (phase space and adiabaticity effects) explicitly bound the frequency range over which the Hawking flux is "approximately" Planck-shaped from both above and below --- the Hawking flux is certainly not exactly Planckian, and there is no compelling physics reason to assume the Hawking photons are uncorrelated.

  2. Geothermal heating

    SciTech Connect (OSTI)

    Aureille, M.

    1982-01-01T23:59:59.000Z

    The aim of the study is to demonstrate the viability of geothermal heating projects in energy and economic terms and to provide nomograms from which an initial estimate may be made without having to use data-processing facilities. The effect of flow rate and temperature of the geothermal water on drilling and on the network, and the effect of climate on the type of housing are considered.

  3. The deterioration in heat transfer to fluids at super-critical pressure and high heat fluxes

    E-Print Network [OSTI]

    Shiralkar, B. S.

    1968-01-01T23:59:59.000Z

    Introduction: Several supercritical steam generators in the American Electric Power system have shown evidence of tube overheat in the lower furnance at the point where the water bulk temperature is about 670 0 F. The ...

  4. Water and Space Heating Heat Pumps 

    E-Print Network [OSTI]

    Kessler, A. F.

    1985-01-01T23:59:59.000Z

    This paper discusses the design and operation of the Trane Weathertron III Heat Pump Water Heating System and includes a comparison of features and performance to other domestic water heating systems. Domestic water is generally provided through...

  5. Water and Space Heating Heat Pumps

    E-Print Network [OSTI]

    Kessler, A. F.

    1985-01-01T23:59:59.000Z

    This paper discusses the design and operation of the Trane Weathertron III Heat Pump Water Heating System and includes a comparison of features and performance to other domestic water heating systems. Domestic water is generally provided through...

  6. Industrial Waste Heat Recovery Using Heat Pipes 

    E-Print Network [OSTI]

    Ruch, M. A.

    1981-01-01T23:59:59.000Z

    For almost a decade now, heat pipes with secondary finned surfaces have been utilized in counter flow heat exchangers to recover sensible energy from industrial exhaust gases. Over 3,000 such heat exchangers are now in service, recovering...

  7. Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow

    E-Print Network [OSTI]

    Boyer, Edmond

    Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S in a rotor-stator cavity subjected to a superimposed throughflow with heat transfer. Nu- merical predictions field from the heat transfer process. The turbulent flux is approximated by a gradient hypothesis

  8. Sensitivity of the South Asian monsoon to elevated and non-elevated heating

    E-Print Network [OSTI]

    Kuang, Zhiming

    for the South Asian monsoon via a ``sensible-heat-driven air-pump''. In their proposed mech- anism, sensible from cold and dry extratropical air or by providing a source of elevated heating. Here we show heat fluxes from mountain slopes produce rising motion that draws surrounding air toward the mountains

  9. Heating systems for heating subsurface formations

    DOE Patents [OSTI]

    Nguyen, Scott Vinh (Houston, TX); Vinegar, Harold J. (Bellaire, TX)

    2011-04-26T23:59:59.000Z

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  10. High flux solar energy transformation

    DOE Patents [OSTI]

    Winston, Roland (Chicago, IL); Gleckman, Philip L. (Chicago, IL); O'Gallagher, Joseph J. (Flossmoor, IL)

    1991-04-09T23:59:59.000Z

    Disclosed are multi-stage systems for high flux transformation of solar energy allowing for uniform solar intensification by a factor of 60,000 suns or more. Preferred systems employ a focusing mirror as a primary concentrative device and a non-imaging concentrator as a secondary concentrative device with concentrative capacities of primary and secondary stages selected to provide for net solar flux intensification of greater than 2000 over 95 percent of the concentration area. Systems of the invention are readily applied as energy sources for laser pumping and in other photothermal energy utilization processes.

  11. High flux solar energy transformation

    DOE Patents [OSTI]

    Winston, R.; Gleckman, P.L.; O'Gallagher, J.J.

    1991-04-09T23:59:59.000Z

    Disclosed are multi-stage systems for high flux transformation of solar energy allowing for uniform solar intensification by a factor of 60,000 suns or more. Preferred systems employ a focusing mirror as a primary concentrative device and a non-imaging concentrator as a secondary concentrative device with concentrative capacities of primary and secondary stages selected to provide for net solar flux intensification of greater than 2000 over 95 percent of the concentration area. Systems of the invention are readily applied as energy sources for laser pumping and in other photothermal energy utilization processes. 7 figures.

  12. Beta ray flux measuring device

    DOE Patents [OSTI]

    Impink, Jr., Albert J. (Murrysville, PA); Goldstein, Norman P. (Murrysville, PA)

    1990-01-01T23:59:59.000Z

    A beta ray flux measuring device in an activated member in-core instrumentation system for pressurized water reactors. The device includes collector rings positioned about an axis in the reactor's pressure boundary. Activated members such as hydroballs are positioned within respective ones of the collector rings. A response characteristic such as the current from or charge on a collector ring indicates the beta ray flux from the corresponding hydroball and is therefore a measure of the relative nuclear power level in the region of the reactor core corresponding to the specific exposed hydroball within the collector ring.

  13. Determining Reactor Flux from Xenon-136 and Cesium-135 in Spent Fuel

    E-Print Network [OSTI]

    A. C. Hayes; Gerard Jungman

    2012-05-30T23:59:59.000Z

    The ability to infer the reactor flux from spent fuel or seized fissile material would enhance the tools of nuclear forensics and nuclear nonproliferation significantly. We show that reactor flux can be inferred from the ratios of xenon-136 to xenon-134 and cesium-135 to cesium-137. If the average flux of a reactor is known, the flux inferred from measurements of spent fuel could help determine whether that spent fuel was loaded as a blanket or close to the mid-plane of the reactor. The cesium ratio also provides information on reactor shutdowns during the irradiation of fuel, which could prove valuable for identifying the reactor in question through comparisons with satellite reactor heat monitoring data. We derive analytic expressions for these correlations and compare them to experimental data and to detailed reactor burn simulations. The enrichment of the original uranium fuel affects the correlations by up to 3 percent, but only at high flux.

  14. Operation of the ORNL High Particle Flux Helicon Plasma Source

    SciTech Connect (OSTI)

    Goulding, Richard Howell [ORNL; Biewer, Theodore M [ORNL; Caughman, John B [ORNL; Chen, Guangye [ORNL; Owen, Larry W [ORNL; Sparks, Dennis O [ORNL

    2011-01-01T23:59:59.000Z

    A high power, high particle flux rf-based helicon plasma source has been constructed at ORNL and operated at power levels up to 30 kW. High-density hydrogen and helium plasmas have been produced. The source has been designed as the basis for a linear plasma materials interaction (PMI) test facility that will generate particle fluxes Gamma(p) > 10(23) M-3 s(-1), and utilize additional ion and electron cyclotron heating to produce high parallel (to the magnetic field) heat fluxes of similar to 10 MW/m(2). An rf-based source for PMI research is of interest because high plasma densities are generated with no internal electrodes, allowing true steady state operation with minimal impurity generation. The ORNL helicon source has a diameter of 15 cm and to-date has operated at a frequency f = 13.56 MHz, with magnetic field strength vertical bar B vertical bar in the antenna region up to similar to 0.15 T. Maximum densities of 3 x 10(19) M-3 in He and 2.5 x 10(19) m(-3) in H have been achieved. Radial density profiles have been seen to be dependent on the axial vertical bar B vertical bar profile.

  15. Operation of the ORNL High Particle Flux Helicon Plasma Source

    SciTech Connect (OSTI)

    Goulding, R. H.; Biewer, T. M.; Caughman, J. B. O.; Chen, G. C.; Owen, L. W.; Sparks, D. O. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6169 (United States)

    2011-12-23T23:59:59.000Z

    A high power, high particle flux rf-based helicon plasma source has been constructed at ORNL and operated at power levels up to 30 kW. High-density hydrogen and helium plasmas have been produced. The source has been designed as the basis for a linear plasma materials interaction (PMI) test facility that will generate particle fluxes {Gamma}{sub p}10{sup 23} m{sup -3} s{sup -1}, and utilize additional ion and electron cyclotron heating to produce high parallel (to the magnetic field) heat fluxes of {approx}10 MW/m{sup 2}. An rf-based source for PMI research is of interest because high plasma densities are generated with no internal electrodes, allowing true steady state operation with minimal impurity generation. The ORNL helicon source has a diameter of 15 cm and to-date has operated at a frequency f = 13.56 MHz, with magnetic field strength |B| in the antenna region up to {approx}0.15 T. Maximum densities of 3x10{sup 19} m{sup -3} in He and 2.5x10{sup 19} m{sup -3} in H have been achieved. Radial density profiles have been seen to be dependent on the axial |B| profile.

  16. Exploring potential R&D collaboration partners through patent analysis based on bibliographic coupling and latent semantic analysis

    E-Print Network [OSTI]

    Park, I.; Jeong, Y.; Yoon, B.; Mortara, L.

    2014-10-22T23:59:59.000Z

    on the citation relationship using patent bibliographic information. Second, latent semantic analysis is utilized based on semantic similarity using patent textual information. The fuel cell membrane electrode assembly (MEA) technology field is selected...

  17. Uncertainty of calorimeter measurements at NREL's high flux solar furnace

    SciTech Connect (OSTI)

    Bingham, C.E.

    1991-12-01T23:59:59.000Z

    The uncertainties of the calorimeter and concentration measurements at the High Flux Solar Furnace (HFSF) at the National Renewable Energy Laboratory (NREL) are discussed. Two calorimeter types have been used to date. One is an array of seven commercially available circular foil calorimeters (gardon or heat flux gages) for primary concentrator peak flux (up to 250 W/cm{sup 2}). The second is a cold-water calorimeter designed and built by the University of Chicago to measure the average exit power of the reflective compound parabolic secondary concentrator used at the HFSF (over 3.3 kW across a 1.6cm{sup {minus}2} exit aperture, corresponding to a flux of about 2 kW/cm{sup 2}). This paper discussed the uncertainties of the calorimeter and pyrheliometer measurements and resulting concentration calculations. The measurement uncertainty analysis is performed according to the ASME/ANSI standard PTC 19.1 (1985). Random and bias errors for each portion of the measurement are analyzed. The results show that as either the power or the flux is reduced, the uncertainties increase. Another calorimeter is being designed for a new, refractive secondary which will use a refractive material to produce a higher average flux (5 kW/cm{sup 2}) than the reflective secondary. The new calorimeter will use a time derivative of the fluid temperature as a key measurement of the average power out of the secondary. A description of this calorimeter and test procedure is also presented, along with a pre-test estimate of major sources of uncertainty. 8 refs., 4 figs., 3 tabs.

  18. Dead heat

    SciTech Connect (OSTI)

    Oppenheimer, M.; Boyle, R.H.

    1990-01-01T23:59:59.000Z

    This paper reports on the prospect of global warming. This paper proposes a workable solution, and a road map for getting there. The author explains how we became addicted to fossil fuels and evokes a bleak picture should this dependence continue. But the book also explores how industry can become a vehicle for solving, instead of precipitating, the global environmental crisis. The decoupling of energy from pollution can be accomplished without sacrificing prosperity by powering the economy with solar energy. Dead Heat takes us step by step to a greenhouse-friendly world fueled only by the sun.

  19. Enhancement of pool boiling heat transfer with electrohydrodynamics and its fundamental study

    E-Print Network [OSTI]

    Raghupathi, Sri Laxmi Priya

    1998-01-01T23:59:59.000Z

    , and 10kV. To conduct this study, an existing low pressure pool boiling apparatus was modified and another high pressure apparatus was designed and built. The fluids were tested on the smooth tube at operating temperatures of 4'C and 20'C, and 19 fins... TWl Tvvo Heat flux of EHD enhancement of boiling (W/m ) Total heat flux with EHD at 10kV (W/m ) Total heat flux with no EHD (W/m ) Minimum cavity mouth radius (m) Rayleigh number Fluid temperature ('C) Pool Saturation temperature ('C) Tube...

  20. Superconducting flux flow digital circuits

    DOE Patents [OSTI]

    Hietala, V.M.; Martens, J.S.; Zipperian, T.E.

    1995-02-14T23:59:59.000Z

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs) are disclosed. Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics. 8 figs.

  1. Dual source heat pump

    DOE Patents [OSTI]

    Ecker, Amir L. (Dallas, TX); Pietsch, Joseph A. (Dallas, TX)

    1982-01-01T23:59:59.000Z

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid provides energy for defrosting the second heat exchanger when operating in the air source mode and also provides a alternate source of heat.

  2. Segmented heat exchanger

    DOE Patents [OSTI]

    Baldwin, Darryl Dean (Lafayette, IN); Willi, Martin Leo (Dunlap, IL); Fiveland, Scott Byron (Metamara, IL); Timmons, Kristine Ann (Chillicothe, IL)

    2010-12-14T23:59:59.000Z

    A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

  3. Quantum Fusion of Domain Walls with Fluxes

    E-Print Network [OSTI]

    S. Bolognesi; M. Shifman; M. B. Voloshin

    2009-07-20T23:59:59.000Z

    We study how fluxes on the domain wall world volume modify quantum fusion of two distant parallel domain walls into a composite wall. The elementary wall fluxes can be separated into parallel and antiparallel components. The parallel component affects neither the binding energy nor the process of quantum merger. The antiparallel fluxes, instead, increase the binding energy and, against naive expectations, suppress quantum fusion. In the small flux limit we explicitly find the bounce solution and the fusion rate as a function of the flux. We argue that at large (antiparallel) fluxes there exists a critical value of the flux (versus the difference in the wall tensions), which switches off quantum fusion altogether. This phenomenon of flux-related wall stabilization is rather peculiar: it is unrelated to any conserved quantity. Our consideration of the flux-related all stabilization is based on substantiated arguments that fall short of complete proof.

  4. HEATING AND COOLING PROTOSTELLAR DISKS

    SciTech Connect (OSTI)

    Hirose, S. [Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showamachi, Kanazawa-ku, Yokohama, Kanagawa 236-0001 (Japan); Turner, N. J., E-mail: shirose@jamstec.go.jp, E-mail: neal.turner@jpl.nasa.gov [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2011-05-10T23:59:59.000Z

    We examine heating and cooling in protostellar disks using three-dimensional radiation-MHD calculations of a patch of the Solar nebula at 1 AU, employing the shearing-box and flux-limited radiation diffusion approximations. The disk atmosphere is ionized by stellar X-rays, well coupled to magnetic fields, and sustains a turbulent accretion flow driven by magnetorotational instability, while the interior is resistive and magnetically dead. The turbulent layers are heated by absorbing the light from the central star and by dissipating the magnetic fields. They are optically thin to their own radiation and cool inefficiently. The optically thick interior in contrast is heated only weakly, by re-emission from the atmosphere. The interior is colder than a classical viscous model and isothermal. The magnetic fields support an extended atmosphere that absorbs the starlight 1.5 times higher than the hydrostatic viscous model. The disk thickness thus measures not the internal temperature, but the magnetic field strength. Fluctuations in the fields move the starlight-absorbing surface up and down. The height ranges between 13% and 24% of the radius over timescales of several orbits, with implications for infrared variability. The fields are buoyant, so the accretion heating occurs higher in the atmosphere than the stresses. The heating is localized around current sheets, caused by magnetorotational instability at lower elevations and by Parker instability at higher elevations. Gas in the sheets is heated above the stellar irradiation temperature, even though accretion is much less than irradiation power when volume averaged. The hot optically thin current sheets might be detectable through their line emission.

  5. HEATING 7. 1 user's manual

    SciTech Connect (OSTI)

    Childs, K.W.

    1991-07-01T23:59:59.000Z

    HEATING is a FORTRAN program designed to solve steady-state and/or transient heat conduction problems in one-, two-, or three- dimensional Cartesian, cylindrical, or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time- and temperature-dependent. The thermal conductivity may be anisotropic. Materials may undergo change of phase. Thermal properties of materials may be input or may be extracted from a material properties library. Heating generation rates may be dependent on time, temperature, and position, and boundary temperatures may be time- and position-dependent. The boundary conditions, which may be surface-to-boundary or surface-to-surface, may be specified temperatures or any combination of prescribed heat flux, forced convection, natural convection, and radiation. The boundary condition parameters may be time- and/or temperature-dependent. General graybody radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING is variably dimensioned and utilizes free-form input. Three steady-state solution techniques are available: point-successive-overrelaxation iterative method with extrapolation, direct-solution (for one-dimensional or two-dimensional problems), and conjugate gradient. Transient problems may be solved using one of several finite-difference schemes: Crank-Nicolson implicit, Classical Implicit Procedure (CIP), Classical Explicit Procedure (CEP), or Levy explicit method (which for some circumstances allows a time step greater than the CEP stability criterion). The solution of the system of equations arising from the implicit techniques is accomplished by point-successive-overrelaxation iteration and includes procedures to estimate the optimum acceleration parameter.

  6. Geophysical and geochemical constraints on geoneutrino fluxes from Earth's mantle

    E-Print Network [OSTI]

    Ond?ej Šrámek; William F. McDonough; Edwin S. Kite; Vedran Leki?; Steve Dye; Shijie Zhong

    2012-10-18T23:59:59.000Z

    Knowledge of the amount and distribution of radiogenic heating in the mantle is crucial for understanding the dynamics of the Earth, including its thermal evolution, the style and planform of mantle convection, and the energetics of the core. Although the flux of heat from the surface of the planet is robustly estimated, the contributions of radiogenic heating and secular cooling remain poorly defined. Constraining the amount of heat-producing elements in the Earth will provide clues to understanding nebula condensation and planetary formation processes in early Solar System. Mantle radioactivity supplies power for mantle convection and plate tectonics, but estimates of mantle radiogenic heat production vary by a factor of more than 20. Recent experimental results demonstrate the potential for direct assessment of mantle radioactivity through observations of geoneutrinos, which are emitted by naturally occurring radionuclides. Predictions of the geoneutrino signal from the mantle exist for several established estimates of mantle composition. Here we present novel analyses, illustrating surface variations of the mantle geoneutrino signal for models of the deep mantle structure, including those based on seismic tomography. These variations have measurable differences for some models, allowing new and meaningful constraints on the dynamics of the planet. An ocean based geoneutrino detector deployed at several strategic locations will be able to discriminate between competing compositional models of the bulk silicate Earth.

  7. Geothermal heat pumps for heating and cooling

    SciTech Connect (OSTI)

    Garg, S.C.

    1994-03-01T23:59:59.000Z

    Naval Facilities Engineering Service Center (NFESC) has been tasked by Naval Shore Facilities Energy Office to evaluate the NAS Patuxent River ground-source heat pump (GHP) installation. A large part of a building`s energy consumption consists of heating and air conditioning for occupant comfort. The space heating requirements are normally met by fossil-fuel-fired equipment or electric resistance heating. Cooling is provided by either air conditioners or heat pumps, both using electricity as an energy source.

  8. New near-wall two-equation model for turbulent heat transport

    SciTech Connect (OSTI)

    Torii, Shuichi [Kagoshima Univ. (Japan). Dept. of Mechanical Engineering; Yang, W.J. [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Mechanical Engineering and Applied Mechanics

    1996-03-01T23:59:59.000Z

    An anisotropic two-equation model is proposed to determine turbulent heat flux in a channel flow up to the wall. The turbulent heat fluxes are given in the form of an anisotropic eddy diffusivity representation in which both the isotropic and anisotropic eddy diffusivities of heat are expressed using the temperature variance {ovr t{sup 2}}, the dissipation rate of temperature fluctuations {var_epsilon}{sub t}, and the velocity gradient. The proposed model is tested through application to an incompressible, two-dimensional, turbulent channel flow with the neglect of buoyant heat transfer. Calculated results are compared with the direct numerical simulation data. It is disclosed from the study that the proposed anisotropic {ovr t{sup 2}}-{var_epsilon}{sub t} heat transfer model predicts reasonably well the distributions of the time-averaged temperature, normal and streamwise turbulent heat fluxes, temperature variance, dissipation rates, and these near-wall budgets.

  9. Enhanced shell-and-tube heat eschangers for the power and process industries. Final report

    SciTech Connect (OSTI)

    Bergles, A.E.; Jensen, M.K.; Somerscales, E.F.; Curcio, L.A. Jr.; Trewin, R.R.

    1994-08-01T23:59:59.000Z

    Single-tube pool boiling tests were performed with saturated pure refrigerants and binary mixtures of refrigerants. Generally, with pure refrigerants, the High Flux surface performed better at the higher heat fluxes compared to the Turbo-B tube, and both enhanced surfaces performed significantly better than smooth surface. In tests of R-11/R-113 mixtures, the enhanced surfaces had much less degradation in heat transfer coefficient due to mixture effects compared to smooth tubes; the largest degradation occurred at a mixture of 25% R-11/75% R-113. Under boiling in saturated aqueous solution of calcium sulfate, with a single tube, effects of fouling were more pronounced at the higher heat fluxes for all surfaces. Two staggered tube bundles were tested with tube pitch-diameter ratios of 1.17 and 1.50. For the pure refrigerant, tests on the smooth-tube bundle indicated that the effects on the heat transfer coefficient of varying mass flux, quality, and tube-bundle geometry were small, except at low heat fluxes. Neither enhanced surface showed any effect with changing mass flux or quality. The binary mixture bundle-boiling tests had results that were very similar to those obtained with the pure refrigerants. When boiling a refrigerant-oil mixture, all three surfaces (smooth, High Flux, and Turbo-B) experienced a degradation in its heat transfer coefficient; no surface studied was found to be immune or vulnerable to the presence of oil than another surface.

  10. An Analysis of Fluxes by Duality

    E-Print Network [OSTI]

    Paul S. Aspinwall

    2005-04-05T23:59:59.000Z

    M-theory on K3xK3 with non-supersymmetry-breaking G-flux is dual to M-theory on a Calabi-Yau threefold times a 2-torus without flux. This allows for a thorough analysis of the effects of flux without relying on supergravity approximations. We discuss several dual pairs showing that the usual rules of G-flux compactifications work well in detail. We discuss how a transition can convert M2-branes into G-flux. We see how new effects can arise at short distances allowing fluxes to obstruct more moduli than one expects from the supergravity analysis.

  11. Mass and heat transfer model of Tubular Solar Still

    SciTech Connect (OSTI)

    Ahsan, Amimul [University Putra Malaysia, Dept. Civil Engineering, Faculty of Engineering, 43400 UPM Serdang, Selangor (Malaysia); Fukuhara, Teruyuki [University of Fukui, Graduate School of Engineering, 3-9-1 Bunkyo, Fukui 910-8507 (Japan)

    2010-07-15T23:59:59.000Z

    In this paper, a new mass and heat transfer model of a Tubular Solar Still (TSS) was proposed incorporating various mass and heat transfer coefficients taking account of the humid air properties inside the still. The heat balance of the humid air and the mass balance of the water vapor in the humid air were formulized for the first time. As a result, the proposed model enabled to calculate the diurnal variations of the temperature, water vapor density and relative humidity of the humid air, and to predict the hourly condensation flux besides the temperatures of the water, cover and trough, and the hourly evaporation flux. The validity of the proposed model was verified using the field experimental results carried out in Fukui, Japan and Muscat, Oman in 2008. The diurnal variations of the calculated temperatures and water vapor densities had a good agreement with the observed ones. Furthermore, the proposed model can predict the daily and hourly production flux precisely. (author)

  12. Heisenberg groups and noncommutative fluxes

    SciTech Connect (OSTI)

    Freed, Daniel S. [Department of Mathematics, University of Texas at Austin, TX 78712 (United States)]. E-mail: dafr@math.utexas.edu; Moore, Gregory W. [Department of Physics, Rutgers University, Piscataway, NJ 08854-8019 (United States); Segal, Graeme [All Souls College, Oxford (United Kingdom)

    2007-01-15T23:59:59.000Z

    We develop a group-theoretical approach to the formulation of generalized abelian gauge theories, such as those appearing in string theory and M-theory. We explore several applications of this approach. First, we show that there is an uncertainty relation which obstructs simultaneous measurement of electric and magnetic flux when torsion fluxes are included. Next, we show how to define the Hilbert space of a self-dual field. The Hilbert space is Z{sub 2}-graded and we show that, in general, self-dual theories (including the RR fields of string theory) have fermionic sectors. We indicate how rational conformal field theories associated to the two-dimensional Gaussian model generalize to (4k+2)-dimensional conformal field theories. When our ideas are applied to the RR fields of string theory we learn that it is impossible to measure the K-theory class of a RR field. Only the reduction modulo torsion can be measured.

  13. ARM - Measurement - Soil moisture flux

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDCnarrowbandheat flux ARM Data Discovery Browse Data

  14. Tropical Cloud Properties and Radiative Heating Profiles

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

    Mather, James

    We have generated a suite of products that includes merged soundings, cloud microphysics, and radiative fluxes and heating profiles. The cloud microphysics is strongly based on the ARM Microbase value added product (Miller et al., 2003). We have made a few changes to the microbase parameterizations to address issues we observed in our initial analysis of the tropical data. The merged sounding product is not directly related to the product developed by ARM but is similar in that it uses the microwave radiometer to scale the radiosonde column water vapor. The radiative fluxes also differ from the ARM BBHRP (Broadband Heating Rate Profile) product in terms of the radiative transfer model and the sampling interval.

  15. Heat-Of-Reaction Chemical Heat Pumps--Possible Configurations 

    E-Print Network [OSTI]

    Kirol, L. D.

    1986-01-01T23:59:59.000Z

    Chemical heat pumps utilize working fluids which undergo reversible chemical changes. Mechanically driven reactive heat pump cycles or, alternatively, heat driven heat pumps in which either heat engine or heat pump working fluid is reactive...

  16. Center vortices as composites of monopole fluxes

    E-Print Network [OSTI]

    Deldar, Sedigheh

    2015-01-01T23:59:59.000Z

    We study the relation between the flux of a center vortex obtained from the center vortex model and the flux formed between monopoles obtained from the Abelian gauge fixing method. Motivated by the Monte Carlo simulations which have shown that almost all monopoles are sitting on the top of vortices, we construct the fluxes of center vortices for $SU(2)$ and $SU(3)$ gauge groups using fractional fluxes of monopoles. Then, we compute the potentials in the fundamental representation induced by center vortices and fractional fluxes of monopoles. We show that by combining the fractional fluxes of monopoles one can produce the center vortex fluxes for $SU(3)$ gauge group in a "center vortex model". Comparing the potentials, we conclude that the fractional fluxes of monopoles attract each other.

  17. HEATING7.3. 1,2, or 3-d Heat Conduction Program

    SciTech Connect (OSTI)

    Childs, K.W. [Oak Ridge National Lab, TN (United States)

    1998-05-01T23:59:59.000Z

    HEATING7.2I and 7.3 is the most recent developmant in a series of heat-transfer codes and obsoletes all previous versions. HEATING can solve steady-state and/or transient heat conduction problems in one, two, or three-dimensional Cartesian, cylindrical coordinates or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time and temperature dependent. The thermal conductivity can be anisotropic. Materials may undergo a change of phase. Thermal properties of materials may be input or may be extracted from a material properties library. Heat-generation rates may be dependent on time, temperature, and position, and boundary temperatures may be time and position dependent. The boundary conditions, which may be surface to environment or surface to surface, may be specified temperatures or any combination of prescribed heat flux, forced convection, natural convection, and radiation. The boundary condition parameters may be time-and/or temperature dependent. General graybody radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING uses a run time memory allocation scheme to avoid having to recompile to match memory requirements for each specific problem. HEATING utilizes free-form input.

  18. Multiple source heat pump

    DOE Patents [OSTI]

    Ecker, Amir L. (Duncanville, TX)

    1983-01-01T23:59:59.000Z

    A heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating a fluid in heat exchange relationship with a refrigerant fluid, at least three refrigerant heat exchangers, one for effecting heat exchange with the fluid, a second for effecting heat exchange with a heat exchange fluid, and a third for effecting heat exchange with ambient air; a compressor for compressing the refrigerant; at least one throttling valve connected at the inlet side of a heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circuit and pump for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and directional flow of refrigerant therethrough for selecting a particular mode of operation. Also disclosed are a variety of embodiments, modes of operation, and schematics therefor.

  19. Parametric modelling of a bellows heat pipe for electronic component cooling

    E-Print Network [OSTI]

    Patnaik, Preetam

    1987-01-01T23:59:59.000Z

    of the fluid. Conduction of heat is governed by Eourier's lcm which is given mathematically as qs = -5. 7'T where q" = heat flux (W/ms) K = conductivity of the material {W/m C) 9 = the three - dimensional del operator T = scalar temperature field. Thus.... Convection is governed by Newton'a Low of Cooling which is given mathemat- ically as lI" = /i(T ? T ) where q" = heat flux (W/m'C) h = heat transfer coefficient (W/ms C) T~ = temperature of body (sC) T~ = temperature of ambient surroundings ( C...

  20. An experimental and theoretical study of radiative and conductive heat transfer in nongray semitransparent media

    E-Print Network [OSTI]

    Eryou, N. Dennis

    1969-01-01T23:59:59.000Z

    One dimensional temperature profiles and heat fluxes within a slab of molten glass were measured experimentally. The glass slab was contained in a platinum foil lined ceramic tray inside a high temperature furnace. An ...

  1. THERMAL PERFORMANCE OF A DUAL-CHANNEL, HELIUM-COOLED, TUNGSTEN HEAT EXCHANGER

    E-Print Network [OSTI]

    California at Los Angeles, University of

    high heat fluxes. The high temperature helium can then be used to power a gas turbine for high the high efficiency power conversion available from new generation gas turbines. It is envisioned

  2. San Bernardino District Heating District Heating Low Temperature...

    Open Energy Info (EERE)

    San Bernardino District Heating District Heating Low Temperature Geothermal Facility Facility San Bernardino District Heating Sector Geothermal energy Type District Heating...

  3. Philip District Heating District Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Philip District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Philip District Heating District Heating Low Temperature Geothermal...

  4. Boise City Geothermal District Heating District Heating Low Temperatur...

    Open Energy Info (EERE)

    Boise City Geothermal District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Boise City Geothermal District Heating District Heating...

  5. Pagosa Springs District Heating District Heating Low Temperature...

    Open Energy Info (EERE)

    Pagosa Springs District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Pagosa Springs District Heating District Heating Low...

  6. Midland District Heating District Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Midland District Heating District Heating Low Temperature Geothermal Facility Facility Midland District Heating Sector Geothermal energy Type District Heating Location Midland,...

  7. Kethcum District Heating District Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Kethcum District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Kethcum District Heating District Heating Low Temperature Geothermal...

  8. Northeast Home Heating Oil Reserve System Heating Oil, PIA Office...

    Energy Savers [EERE]

    Northeast Home Heating Oil Reserve System Heating Oil, PIA Office of Fossil Energy Headquaters Northeast Home Heating Oil Reserve System Heating Oil, PIA Office of Fossil Energy...

  9. RADIATIVE HEATING OF THE SOLAR CORONA

    SciTech Connect (OSTI)

    Moran, Thomas G., E-mail: moran@grace.nascom.nasa.gov [Physics Department, Catholic University of America, 200 Hannan Hall, Washington, DC 20064 (United States) and NASA/GSFC, Code 671, Greenbelt, MD 20771 (United States)

    2011-10-20T23:59:59.000Z

    We investigate the effect of solar visible and infrared radiation on electrons in the Sun's atmosphere using a Monte Carlo simulation of the wave-particle interaction and conclude that sunlight provides at least 40% and possibly all of the power required to heat the corona, with the exception of dense magnetic flux loops. The simulation uses a radiation waveform comprising 100 frequency components spanning the solar blackbody spectrum. Coronal electrons are heated in a stochastic manner by low coherence solar electromagnetic radiation. The wave 'coherence time' and 'coherence volume' for each component is determined from optical theory. The low coherence of solar radiation allows moving electrons to gain energy from the chaotic wave field which imparts multiple random velocity 'kicks' to these particles causing their velocity distribution to broaden or heat. Monte Carlo simulations of broadband solar radiative heating on ensembles of 1000 electrons show heating at per particle levels of 4.0 x 10{sup -21} to 4.0 x 10{sup -20} W, as compared with non-loop radiative loss rates of {approx}1 x 10{sup -20} W per electron. Since radiative losses comprise nearly all of the power losses in the corona, sunlight alone can explain the elevated temperatures in this region. The volume electron heating rate is proportional to density, and protons are assumed to be heated either by plasma waves or through collisions with electrons.

  10. Heat Pump for High School Heat Recovery 

    E-Print Network [OSTI]

    Huang, K.; Wang, H.; Zhou, X.

    2006-01-01T23:59:59.000Z

    The heat pump system used for recycling and reusing waste heat in s high school bathroom was minutely analyzed in its coefficient of performance, onetime utilization ratio of energy, economic property and so on. The results showed that this system...

  11. Industrial Waste Heat Recovery Using Heat Pipes

    E-Print Network [OSTI]

    Ruch, M. A.

    1981-01-01T23:59:59.000Z

    -expanding variety of industrial processes. One notable application in recent years has been for combustion airs preheat of fired heaters in petroleum refineries and petrochemical plants. Another recent development has been a waste heat recovery boiler using heat...

  12. Method and apparatus for enhanced heat recovery from steam generators and water heaters

    DOE Patents [OSTI]

    Knight, Richard A.; Rabovitser, Iosif K.; Wang, Dexin

    2006-06-27T23:59:59.000Z

    A heating system having a steam generator or water heater, at least one economizer, at least one condenser and at least one oxidant heater arranged in a manner so as to reduce the temperature and humidity of the exhaust gas (flue gas) stream and recover a major portion of the associated sensible and latent heat. The recovered heat is returned to the steam generator or water heater so as to increase the quantity of steam generated or water heated per quantity of fuel consumed. In addition, a portion of the water vapor produced by combustion of fuel is reclaimed for use as feed water, thereby reducing the make-up water requirement for the system.

  13. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  14. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, G.

    1982-06-16T23:59:59.000Z

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  15. Locating Heat Recovery Opportunities 

    E-Print Network [OSTI]

    Waterland, A. F.

    1981-01-01T23:59:59.000Z

    Basic concepts of heat recovery are defined as they apply to the industrial community. Methods for locating, ranking, and developing heat recovery opportunities are presented and explained. The needs for useful heat 'sinks' are emphasized as equal...

  16. Locating Heat Recovery Opportunities

    E-Print Network [OSTI]

    Waterland, A. F.

    1981-01-01T23:59:59.000Z

    Basic concepts of heat recovery are defined as they apply to the industrial community. Methods for locating, ranking, and developing heat recovery opportunities are presented and explained. The needs for useful heat 'sinks' are emphasized as equal...

  17. Estimation of advective fluxes from CO2 flux profile observations at the Cabauw Tower

    E-Print Network [OSTI]

    Stoffelen, Ad

    Estimation of advective fluxes from CO2 flux profile observations at the Cabauw Tower Kasper O profile observations at the Cabauw Tower Version 1.0 Date April 2012 Status Final #12;#12;Estimation of Advective Fluxes from CO2 Flux Profile Observations at the Cabauw Tower Master of Science Thesis Kasper O

  18. Effect of turbulent heat transfer on continuous ingot solidification

    SciTech Connect (OSTI)

    Shyy, W.; Chen, M.H. (Univ. of Florida, Gainesville, FL (United States). Dept. of Aerospace Engineering); Pang, Y.; Wei, D.Y. (GE Aircraft Engines, Engineering Materials Technology Labs., Lynn, MA (United States)); Hunter, G.B. (GE Aircraft Engines, Engineering Materials Technology Labs., Cincinnati, OH (United States))

    1993-01-01T23:59:59.000Z

    For many continuous ingot casting processes, turbulent heat transfer in the molten pool plays a critical role which, along with buoyancy and surface tension, is responsible for the quality of the end products. Based on a modified low Reynolds number K-[epsilon] two-equation closure, accounting for the phase change and mushy zone formation, the effect of turbulent heat transfer on the solidification characteristics during titanium alloy ingot casting in an electron beam melting process is investigated. The overall heat transfer rate is enhanced by turbulent transport via two sources, one through the correlated velocity and temperature fluctuations present for both single- and multi-phase flows, and the other through the correlated velocity and release of latent heat fluctuations which are unique to the flows with phase change. The roles played by both mechanisms are identified and assessed. The present turbulence model predicts that although the mushy zone defined by the mean temperature field is generally of substantial thickness as a result of the convection effect, the actual instantaneous zone thickness varies substantially due to turbulence effect. This finding is in contrast to the traditionally held viewpoint, based on the conduction analysis, of a generally thin mushy zone. The impact of turbulent heat transfer on local dendrite formation and remelting is illustrated and the issues involved in model development highlighted.

  19. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, R.R.

    1984-07-16T23:59:59.000Z

    This invention relates to a heat exchanger for waste heat recovery from high temperature industrial exhaust streams. In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  20. Theoretical Design of Thermosyphon for Process Heat Transfer from NGNP to Hydrogen Plant

    SciTech Connect (OSTI)

    Piyush Sabharwall; Mike Patterson; Fred Gunnerson

    2008-09-01T23:59:59.000Z

    The Next Generation Nuclear Plant (NGNP) will most likely produce electricity and process heat, with both being considered for hydrogen production. To capture nuclear process heat, and transport it to a distant industrial facility requires a high temperature system of heat exchangers, pumps and/or compressors. The heat transfer system is particularly challenging not only due to the elevated temperatures (up to ~ 1300K) and industrial scale power transport (=50 MW), but also due to a potentially large separation distance between the nuclear and industrial plants (100+m) dictated by safety and licensing mandates. The work reported here is the preliminary analysis of two-phase thermosyphon heat transfer performance with alkali metals. A thermosyphon is a device for transporting heat from one point to another with quite extraordinary properties. In contrast to single-phased forced convective heat transfer via ‘pumping a fluid’, a thermosyphon (also called a wickless heat pipe) transfers heat through the vaporization / condensing process. The condensate is further returned to the hot source by gravity, i.e. without any requirement of pumps or compressors. With this mode of heat transfer, the thermosyphon has the capability to transport heat at high rates over appreciable distances, virtually isothermally and without any requirement for external pumping devices. Two-phase heat transfer by a thermosyphon has the advantage of high enthalpy transport that includes the sensible heat of the liquid, the latent heat of vaporization, and vapor superheat. In contrast, single-phase forced convection transports only the sensible heat of the fluid. Additionally, vapor-phase velocities within a thermosyphon are much greater than single-phase liquid velocities within a forced convective loop. Thermosyphon performance can be limited by the sonic limit (choking) or vapor flow and/or by condensate entrainment. Proper thermosyphon requires analysis of both.

  1. Total Space Heat-

    Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

    Commercial Buildings Energy Consumption Survey: Energy End-Use Consumption Tables Total Space Heat- ing Cool- ing Venti- lation Water Heat- ing Light- ing Cook- ing Refrig- eration...

  2. Total Space Heat-

    Gasoline and Diesel Fuel Update (EIA)

    Revised: December, 2008 Total Space Heat- ing Cool- ing Venti- lation Water Heat- ing Light- ing Cook- ing Refrig- eration Office Equip- ment Com- puters Other All Buildings...

  3. As-Run Thermal Analysis of the GTL-1 Experiment Irradiated in the ATR South Flux Trap

    SciTech Connect (OSTI)

    Donna P. Guillen

    2011-05-01T23:59:59.000Z

    The GTL-1 experiment was conducted to assess corrosion the performance of the proposed Boosted Fast Flux Loop booster fuel at heat flux levels {approx}30% above the design operating condition. Sixteen miniplates fabricated from 25% enriched, high-density U3Si2/Al dispersion fuel with 6061 aluminum cladding were subjected to peak beginning of cycle (BOC) heat fluxes ranging from 411 W/cm2 to 593 W/cm2. Miniplates fabricated with three different fuel variations (without fines, annealed, and with standard powder) performed equally well, with negligible irradiation-induced swelling and a normal fission density gradient. Both the standard and the modified prefilm procedures produced hydroxide films that adequately protected the miniplates from failure. A detailed finite element model was constructed to calculate temperatures and heat flux for an as-run cycle average effective south lobe power of 25.4 MW(t). Results of the thermal analysis are given at four times during the cycle: BOC at 0 effective full power days (EFPD), middle of cycle (MOC) at 18 EFPD, MOC at 36 EFPD, and end of cycle at 48.9 EFPD. The highest temperatures and heat fluxes occur at the BOC and decrease in a linear manner throughout the cycle. Miniplate heat flux levels and fuel, cladding, hydroxide, and coolant-hydroxide interface temperatures were calculated using the average measured hydroxide thickness on each miniplate. The hydroxide layers are the largest on miniplates nearest to the core midplane, where heat flux and temperature are highest. The hydroxide layer thickness averages 20.4 {mu}m on the six hottest miniplates (B3, B4, C1, C2, C3, and C4). This tends to exacerbate the heating of these miniplates, since a thicker hydroxide layer reduces the heat transfer from the fuel to the coolant. These six hottest miniplates have the following thermal characteristics at BOC: (1) Peak fuel centerline temperature >300 C; (2) Peak cladding temperature >200 C; (3) Peak hydroxide temperature >190 C; (4) Peak hydroxide-water interface temperature >140 C; and (5) Peak heat flux >565 W/cm2.

  4. Efficient Heat Storage Materials: Metallic Composites Phase-Change Materials for High-Temperature Thermal Energy Storage

    SciTech Connect (OSTI)

    None

    2011-11-21T23:59:59.000Z

    HEATS Project: MIT is developing efficient heat storage materials for use in solar and nuclear power plants. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at night—when the sun’s not out—to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. MIT is designing nanostructured heat storage materials that can store a large amount of heat per unit mass and volume. To do this, MIT is using phase change materials, which absorb a large amount of latent heat to melt from solid to liquid. MIT’s heat storage materials are designed to melt at high temperatures and conduct heat well—this makes them efficient at storing and releasing heat and enhances the overall efficiency of the thermal storage and energy-generation process. MIT’s low-cost heat storage materials also have a long life cycle, which further enhances their efficiency.

  5. Slipping Magnetic Reconnection Triggering a Solar Eruption of a Triangle-flag Flux Rope

    E-Print Network [OSTI]

    Li, Ting

    2014-01-01T23:59:59.000Z

    We firstly report the simultaneous activities of a slipping motion of flare loops and a slipping eruption of a flux rope in 131 {\\AA} and 94 {\\AA} channels on 2014 February 02. The east hook-like flare ribbon propagated slippingly at a speed of about 50 km s$^{-1}$, which lasted about 40 min and extended by more than 100 Mm, but the west flare ribbon moved in the opposite direction with a speed of 30 km s$^{-1}$. At the later phase of the flare activity, a "bi-fan" system of flare loops was well developed. The east footpoints of the flux rope showed an apparent slipping motion along the hook of the ribbon, simultaneously the fine structures of the flux rope rose up rapidly at a speed of 130 km s$^{-1}$, much faster the whole flux rope. We infer that the east footpoints of the flux rope are successively heated by a slipping magnetic reconnection during the flare, which results in the apparent slippage of the flux rope. The slipping motion delineates a "triangle-flag surface" of the flux rope, implying that the...

  6. Heat-pipe gas-combustion system endurance test for Stirling engine. Final report, May 1990-September 1990

    SciTech Connect (OSTI)

    Mahrle, P.

    1990-12-01T23:59:59.000Z

    Stirling Thermal Motors, Inc., (STM) has been developing a general purpose Heat Pipe Gas Combustion System (HPGC) suitable for use with the STM4-120 Stirling engine. The HPGC consists of a parallel plate recuperative preheater, a finned heat pipe evaporator and a film cooled gas combustor. A principal component of the HPGC is the heat pipe evaporator which collects and distributes the liquid sodium over the heat transfer surfaces. The liquid sodium evaporates and flows to the condensers where it delivers its latent heat. The report presents test results of endurance tests run on a Gas-Fired Stirling Engine (GFSE). Tests on a dynamometer test stand yielded 67 hours of engine operation at power levels over 10 kW (13.5 hp) with 26 hours at power levels above 15 kW (20 hp). Total testing of the engine, including both motoring tests and engine operation, yielded 245 hours of engine run time.

  7. Measured Effects of Retrofits - A Refrigerant Oil Additive and a Condenser Spray Device - On the Cooling Performance of a Heat Pump 

    E-Print Network [OSTI]

    Levins, W. P.; Sand, J. R.; Baxter, V. D.; Linkous, R. S.

    1996-01-01T23:59:59.000Z

    for their sponsorship of the tests of the condenser spray unit. We also express our thanks to Keith Rice of Oak Ridge National Laboratories for the modeling work he performed to estimate the latent capacities used in the condenser sprayer testing. Based..., "The Oak Ridge Heat Pump Models: I. A Steawtate Computer Design Model For Air-To-Air Heat Pumps'', OWCON-8OlR1, August 1 983. 5. Kays, W.M., and A.L. London, "Compact Heat Exchangers ", 3rd edition, McGraw-Hill, New York, pp. 14-16. 6. Levins, W...

  8. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, Lance D. (Shelly, ID)

    1988-01-01T23:59:59.000Z

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation.

  9. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, L.D.

    1987-02-11T23:59:59.000Z

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

  10. Mass and Heat Recovery 

    E-Print Network [OSTI]

    Hindawai, S. M.

    2010-01-01T23:59:59.000Z

    In the last few years heat recovery was under spot and in air conditioning fields usually we use heat recovery by different types of heat exchangers. The heat exchanging between the exhaust air from the building with the fresh air to the building...

  11. Anisotropic turbulent model for solar coronal heating

    E-Print Network [OSTI]

    B. Bigot; S. Galtier; H. Politano

    2008-08-26T23:59:59.000Z

    Context : We present a self-consistent model of solar coronal heating, originally developed by Heyvaert & Priest (1992), in which we include the dynamical effect of the background magnetic field along a coronal structure by using exact results from wave MHD turbulence (Galtier et al. 2000). Aims : We evaluate the heating rate and the microturbulent velocity for comparison with observations in the quiet corona, active regions and also coronal holes. Methods :The coronal structures are assumed to be in a turbulent state maintained by the slow erratic motions of the magnetic footpoints. A description for the large-scale and the unresolved small-scale dynamics are given separately. From the latter, we compute exactly (or numerically for coronal holes) turbulent viscosites that are finally used in the former to close self-consistently the system and derive the heating flux expression. Results : We show that the heating rate and the turbulent velocity compare favorably with coronal observations. Conclusions : Although the Alfven wave turbulence regime is strongly anisotropic, and could reduce a priori the heating efficiency, it provides an unexpected satisfactory model of coronal heating for both magnetic loops and open magnetic field lines.

  12. Thulium-170 heat source

    DOE Patents [OSTI]

    Walter, Carl E. (Pleasanton, CA); Van Konynenburg, Richard (Livermore, CA); VanSant, James H. (Tracy, CA)

    1992-01-01T23:59:59.000Z

    An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.

  13. Thermoelectric heat exchange element

    DOE Patents [OSTI]

    Callas, James J. (Peoria, IL); Taher, Mahmoud A. (Peoria, IL)

    2007-08-14T23:59:59.000Z

    A thermoelectric heat exchange module includes a first substrate including a heat receptive side and a heat donative side and a series of undulatory pleats. The module may also include a thermoelectric material layer having a ZT value of 1.0 or more disposed on at least one of the heat receptive side and the heat donative side, and an electrical contact may be in electrical communication with the thermoelectric material layer.

  14. Mass and Heat Recovery

    E-Print Network [OSTI]

    Hindawai, S. M.

    2010-01-01T23:59:59.000Z

    - 1 - MASS AND HEAT RECOVERY SYSTEM SALAH MAHMOUD HINDAWI DIRECTOR HINDAWI FOR ENGINEERING SERVICES & CONTRACTING NEW DAMIETTA , EGYPT ABSTRACT : In the last few years heat recovery was under spot . and in air conditioning fields... ) as a heat recovery . and I use the water as a mass recovery . The source of mass and heat recovery is the condensate water which we were dispose and connect it to the drain lines . THE BENEFIT OF THIS SYSTEM ARE : 1) Using the heat energy from...

  15. Atmospheric neutrino flux at INO site

    SciTech Connect (OSTI)

    Honda, Morihiro [Institute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8582 (Japan)

    2011-11-23T23:59:59.000Z

    To illustrate the calculation of the atmospheric neutrino flux, we briefly explain our calculation scheme and important components, such as primary cosmic ray spectra, interaction model, and geomagnetic model. Then, we calculate the atmospheric neutrino flux at INO site in our calculation scheme. We compare the calculated atmospheric neutrino fluxes predicted at INO with those at other major neutrino detector sites, especially that at SK site.

  16. Calculation of thermal fluxes of plasma torch reradiation under the action of laser radiation on a condensed target

    SciTech Connect (OSTI)

    Rudenko, V. V. [Russian Federation Ministry of Defense, 12th Central Scientific Research Institute (Russian Federation)

    2010-12-15T23:59:59.000Z

    The problem of laser deposition with allowance for thermal radiation transport inside and outside the laser torch is considered in a multigroup approximation. The energy fluxes of laser torch thermal radiation onto a target in the far and near zones are calculated as functions of time and the character of the exposure. It is shown that absorption of thermal fluxes in the substrate and target in the course of laser deposition results in their substantial heating. The possibility of diagnosing thermal radiation fluxes from the laser torch by using photodetectors is demonstrated.

  17. On solar neutrino fluxes in radiochemical experiments

    E-Print Network [OSTI]

    R. N. Ikhsanov; Yu. N. Gnedin; E. V. Miletsky

    2005-12-08T23:59:59.000Z

    We analyze fluctuations of the solar neutrino flux using data from the Homestake, GALLEX, GNO, SAGE and Super Kamiokande experiments. Spectral analysis and direct quantitative estimations show that the most stable variation of the solar neutrino flux is a quasi-five-year periodicity. The revised values of the mean solar neutrino flux are presented in Table 4. They were used to estimate the observed pp-flux of the solar electron neutrinos near the Earth. We consider two alternative explanations for the origin of a variable component of the solar neutrino deficit.

  18. Fluxing agent for metal cast joining

    DOE Patents [OSTI]

    Gunkel, Ronald W. (Lower Burrell, PA); Podey, Larry L. (Greensburg, PA); Meyer, Thomas N. (Murrysville, PA)

    2002-11-05T23:59:59.000Z

    A method of joining an aluminum cast member to an aluminum component. The method includes the steps of coating a surface of an aluminum component with flux comprising cesium fluoride, placing the flux coated component in a mold, filling the mold with molten aluminum alloy, and allowing the molten aluminum alloy to solidify thereby joining a cast member to the aluminum component. The flux preferably includes aluminum fluoride and alumina. A particularly preferred flux includes about 60 wt. % CsF, about 30 wt. % AlF.sub.3, and about 10 wt. % Al.sub.2 O.sub.3.

  19. Cloud properties and associated radiative heating rates in the tropical western Pacific

    E-Print Network [OSTI]

    Cloud properties and associated radiative heating rates in the tropical western Pacific James H set of atmospheric remote sensing instruments at sites around the world, including three radiative fluxes and heating rates. Maxima in cloud occurrence are found in the boundary layer and the upper

  20. Modeling of the recycling particle flux and electron particle transport in the DIII-D tokamak

    SciTech Connect (OSTI)

    Baker, D.R.; Jackson, G.L. [General Atomics, San Diego, CA (United States); Maingi, R. [Oak Ridge Associated Universities, Inc., TN (United States); Owen, L.W. [Oak Ridge National Lab., TN (United States); Porter, G.D. [Lawrence Livermore National Lab., CA (United States)

    1996-10-01T23:59:59.000Z

    One of the most difficult aspects of performing an equilibrium particle transport analysis in a diverted tokamak is the determination of the particle flux which enters the plasma after recycling from the divertor plasma, the divertor target plates or the vessel wall. An approach which has been utilized in the past is to model the edge, scrape-off layer (SOL), and divertor plasma to match measured plasma parameters and then use a neutral transport code to obtain an edge recycling flux while trying to match the measured divertor D(x emissivity. Previous simulations were constrained by electron density (n{sub e}) and temperature (T{sub e}), ion temperature (T{sub i}) data at the outer midplane, divertor heat flux from infrared television cameras, and n{sub e}, T{sub e} and particle flux at the target from fixed Langmuir probes, along with the divertor D{sub {alpha}} emissivity. In this paper, we present results of core fueling calculations from the 2-D modeling for ELM-free discharges, constrained by data from the new divertor diagnostics. In addition, we present a simple technique for estimating the recycling flux just after the L-H transition and demonstrate how this technique is supported by the detailed modeling. We will show the effect which inaccuracies in the recycling flux have on the calculated particle flux in the plasma core. For some specific density profiles, it is possible to separate the convective flux from the conductive flux. The diffusion coefficients obtained show a sharp decrease near a normalized radius of 0.9 indicating the presence of a transport barrier.

  1. Heat Integrate Heat Engines in Process Plants

    E-Print Network [OSTI]

    Hindmarsh, E.; Boland, D.; Townsend, D. W.

    ~C. T min Table 3. Problem Table Algorithm Applied to Petrochemicals Process Interval GJ ltiour 'Temperatures ! C! 2 ) ? ~ Cold. Hot Aecumulated Heat Heat FJ.owa Interval Streams StrePlS Deficit. Input OUtput -OUtt!utInput. 20 30 -2... of heat which can be passed on in this manner is performed in column 2 and column 3 of Table 3. It is initially assumed that the heat input from external utilities is zero. This is represented in Table 3 by a zero input to the top interval. Having...

  2. Finite element analysis of heat transport in a hydrothermal zone

    SciTech Connect (OSTI)

    Bixler, N.E.; Carrigan, C.R.

    1987-01-01T23:59:59.000Z

    Two-phase heat transport in the vicinity of a heated, subsurface zone is important for evaluation of nuclear waste repository design and estimation of geothermal energy recovery, as well as prediction of magma solidification rates. Finite element analyses of steady, two-phase, heat and mass transport have been performed to determine the relative importance of conduction and convection in a permeable medium adjacent to a hot, impermeable, vertical surface. The model includes the effects of liquid flow due to capillarity and buoyancy and vapor flow due to pressure gradients. Change of phase, with its associated latent heat effects, is also modeled. The mechanism of capillarity allows for the presence of two-phase zones, where both liquid and vapor can coexist, which has not been considered in previous investigations. The numerical method employs the standard Galerkin/finite element method, using eight-node, subparametric or isoparametric quadrilateral elements. In order to handle the extreme nonlinearities inherent in two-phase, nonisothermal, porous-flow problems, steady-state results are computed by integrating transients out to a long time (a method that is highly robust).

  3. A testing and HVAC design methodology for air-to-air heat pipe heat exchangers

    SciTech Connect (OSTI)

    Guo, P.; Ciepliski, D.L.; Besant, R.W. [Univ. of Saskatchewan, Saskatoon, Saskatchewan (Canada). Dept. of Mechanical Engineering

    1998-10-01T23:59:59.000Z

    Air-to-air heat pipe heat exchangers were tested using ASHRAE Standard 84-1991 as a guide. Some changes are introduced for the test facility and methods of calculating effectiveness. ASME PTC 19.1-1985 is used as a guide for uncertainty analysis. Tests were done for a range of mass flux [1.574 to 2.912 kg/(m{sup 2}{center_dot}s)], ratios of mass flow rates (0.6 to 1.85), supply air temperatures ({minus}10 C to 40 C), and heat exchanger tilt angles ({minus}8.9{degree} to 11.2{degree}). Because humidity changes in the exhaust and supply air streams were negligible, only the effectiveness of sensible and of total energy was considered. Measured and calculated results show significant variations in the effectiveness of sensible and of total energy, and uncertainties with each independent variable. For balanced exhaust and supply flow rates at {minus}10 C supply air temperature and 1.574 kg/(m{sup 2}{center_dot}s) mass flux, the measured effectiveness for sensible and total energy was calculated to be 0.48 and 0.44, respectively, with uncertainties of 0.057 and 0.052. These measurements decreased to 0.42 and 0.37, with uncertainties of 0.016 and 0.018 for a mass flux of 2.912 kg/(m{sup 2}{center_dot}s). Because water vapor condensation effects were small or negligible, the difference between the effectiveness for the sensible and total energy was within the overlapping uncertainty range of each. Based on counterflow heat exchanger theory and convective heat transfer equations, expressions are presented to extrapolate the effectiveness data between and beyond the measured data points. These effectiveness equations, which represent the variation in effectiveness with several independent operating variables, are used for HVAC design that is aimed at achieving minimum life-cycle costs.

  4. Task Modeling in Imitation Learning using Latent Variable Models Carl Henrik Ek, Dan Song, Kai Huebner and Danica Kragic

    E-Print Network [OSTI]

    Ek, Carl Henrik

    in the sensorimotor systems, [4] proposed a coherent control, trajectory optimization, and action planningTask Modeling in Imitation Learning using Latent Variable Models Carl Henrik Ek, Dan Song, Kai about different manipulation tasks from scene observations. In this paper we present a probabilistic

  5. Thermal analysis of an indirectly heat pulsed non-volatile phase change material microwave switch

    SciTech Connect (OSTI)

    Young, Robert M., E-mail: rm.young@ngc.com; El-Hinnawy, Nabil; Borodulin, Pavel; Wagner, Brian P.; King, Matthew R.; Jones, Evan B.; Howell, Robert S.; Lee, Michael J. [Northrop Grumman Corp., Electronic Systems, P.O. Box 1521, Baltimore, Maryland 21203 (United States)

    2014-08-07T23:59:59.000Z

    We show the finite element simulation of the melt/quench process in a phase change material (GeTe, germanium telluride) used for a radio frequency switch. The device is thermally activated by an independent NiCrSi (nickel chrome silicon) thin film heating element beneath a dielectric separating it electrically from the phase change layer. A comparison is made between the predicted and experimental minimum power to amorphize (MPA) for various thermal pulse powers and pulse time lengths. By including both the specific heat and latent heat of fusion for GeTe, we find that the MPA and the minimum power to crystallize follow the form of a hyperbola on the power time effect plot. We also find that the simulated time at which the entire center GeTe layer achieves melting accurately matches the MPA curve for pulse durations ranging from 75–1500?ns and pulse powers from 1.6–4?W.

  6. HEATING6 verification

    SciTech Connect (OSTI)

    Bryan, C.B.; Childs, K.W.; Giles, G.E.

    1986-12-01T23:59:59.000Z

    The HEATING series of general purpose, finite-difference, conduction heat transfer codes have been in use for many years. During this time the codes have been used extensively, and a general confidence has been developed in regard to their accuracy. However, there has never been a formal verification in a published, citable document. This report documents just such a verification study for the latest code in the HEATING series, HEATING6. This study confirms that HEATING6 is capable of producing accurate results for a large class of heat transfer problems. 11 refs., 170 figs., 82 tabs.

  7. Heat Pump for High School Heat Recovery

    E-Print Network [OSTI]

    Huang, K.; Wang, H.; Zhou, X.

    2006-01-01T23:59:59.000Z

    ) [3] Yayun FAN. Experimental study on a heat pump technology in solar thermal utilization[J]. Acta Energiae Solaris Sinica, Oct.,2002; Vol.23,No.5 ? 581-585.(In Chinese) [4] Nengxi JIANG. Air-conditioning Heat Pump Technology and Its Applications...

  8. Berry-Phase induced Heat Pumping and its Impact on the Fluctuation Theorem

    E-Print Network [OSTI]

    Ren, Jie; Li, Baowen

    2010-01-01T23:59:59.000Z

    Applying adiabatic, cyclic two parameter modulations we investigate quantum heat transfer across an anharmonic molecular junction contacted with two heat baths. We demonstrate that the pumped heat typically exhibits a Berry phase effect in providing an additional geometric contribution to heat flux. Remarkably, a robust fractional quantized geometric phonon response is identified as well. The presence of this geometric phase contribution in turn causes a breakdown of the fluctuation theorem of the Gallavotti-Cohen type for quantum heat transfer. This can be restored only if (i) the geometric phase contribution vanishes and if (ii) the cyclic protocol preserves the detailed balance symmetry.

  9. Data system for automatic flux mapping applications

    SciTech Connect (OSTI)

    Couch, R.D.; Kasinoff, A.M.; Neuner, J.A.; Oates, R.M.

    1980-12-16T23:59:59.000Z

    In an automatic flux mapping system utilizing a microprocessor for control and data information processing, signals from the incore detectors providing the flux mapping operation are converted to a frequency link and are made available to the microprocessor via a programmable timer thus minimizing the participation of the microprocessor so that the microprocessor can be made more available to satisfy other tasks.

  10. URANIUM MILL TAILINGS RADON FLUX CALCULATIONS

    E-Print Network [OSTI]

    URANIUM MILL TAILINGS RADON FLUX CALCULATIONS PIÃ?ON RIDGE PROJECT MONTROSE COUNTY, COLORADO Inc. (Golder) was commissioned by EFRC to evaluate the operations of the uranium mill tailings storage in this report were conducted using the WISE Uranium Mill Tailings Radon Flux Calculator, as updated on November

  11. PHELIX for flux compression studies

    SciTech Connect (OSTI)

    Turchi, Peter J [Los Alamos National Laboratory; Rousculp, Christopher L [Los Alamos National Laboratory; Reinovsky, Robert E [Los Alamos National Laboratory; Reass, William A [Los Alamos National Laboratory; Griego, Jeffrey R [Los Alamos National Laboratory; Oro, David M [Los Alamos National Laboratory; Merrill, Frank E [Los Alamos National Laboratory

    2010-06-28T23:59:59.000Z

    PHELIX (Precision High Energy-density Liner Implosion eXperiment) is a concept for studying electromagnetic implosions using proton radiography. This approach requires a portable pulsed power and liner implosion apparatus that can be operated in conjunction with an 800 MeV proton beam at the Los Alamos Neutron Science Center. The high resolution (< 100 micron) provided by proton radiography combined with similar precision of liner implosions driven electromagnetically can permit close comparisons of multi-frame experimental data and numerical simulations within a single dynamic event. To achieve a portable implosion system for use at high energy-density in a proton laboratory area requires sub-megajoule energies applied to implosions only a few cms in radial and axial dimension. The associated inductance changes are therefore relatively modest, so a current step-up transformer arrangement is employed to avoid excessive loss to parasitic inductances that are relatively large for low-energy banks comprising only several capacitors and switches. We describe the design, construction and operation of the PHELIX system and discuss application to liner-driven, magnetic flux compression experiments. For the latter, the ability of strong magnetic fields to deflect the proton beam may offer a novel technique for measurement of field distributions near perturbed surfaces.

  12. A Framework for Incorporating General Domain Knowledge into Latent Dirichlet Allocation using First-Order Logic

    SciTech Connect (OSTI)

    Andrzejewski, D; Zhu, X; Craven, M; Recht, B

    2011-01-18T23:59:59.000Z

    Topic models have been used successfully for a variety of problems, often in the form of application-specific extensions of the basic Latent Dirichlet Allocation (LDA) model. Because deriving these new models in order to encode domain knowledge can be difficult and time-consuming, we propose the Fold-all model, which allows the user to specify general domain knowledge in First-Order Logic (FOL). However, combining topic modeling with FOL can result in inference problems beyond the capabilities of existing techniques. We have therefore developed a scalable inference technique using stochastic gradient descent which may also be useful to the Markov Logic Network (MLN) research community. Experiments demonstrate the expressive power of Fold-all, as well as the scalability of our proposed inference method.

  13. Consolidated Electric Cooperative- Heat Pump and Water Heating Rebates

    Broader source: Energy.gov [DOE]

    Consolidated Electric Cooperative provides rebates to residential customers who install electric water heaters, dual-fuel heating system or geothermal heat pumps. A dual-fuel heating systems...

  14. Final Technical Report for "Radiative Heating Associated with Tropical Convective Cloud Systems: Its Importance at Meso and Global Scales"

    SciTech Connect (OSTI)

    Schumacher, Courtney

    2012-12-13T23:59:59.000Z

    Heating associated with tropical cloud systems drive the global circulation. The overall research objectives of this project were to i) further quantify and understand the importance of heating in tropical convective cloud systems with innovative observational techniques, and ii) use global models to determine the large-scale circulation response to variability in tropical heating profiles, including anvil and cirrus cloud radiative forcing. The innovative observational techniques used a diversity of radar systems to create a climatology of vertical velocities associated with the full tropical convective cloud spectrum along with a dissection of the of the total heating profile of tropical cloud systems into separate components (i.e., the latent, radiative, and eddy sensible heating). These properties were used to validate storm-scale and global climate models (GCMs) and were further used to force two different types of GCMs (one with and one without interactive physics). While radiative heating was shown to account for about 20% of the total heating and did not have a strong direct response on the global circulation, the indirect response was important via its impact on convection, esp. in how radiative heating impacts the tilt of heating associated with the Madden-Julian Oscillation (MJO), a phenomenon that accounts for most tropical intraseasonal variability. This work shows strong promise in determining the sensitivity of climate models and climate processes to heating variations associated with cloud systems.

  15. Experimental investigation of piston heat transfer under conventional diesel and reactivity-controlled compression ignition combustion regimes

    SciTech Connect (OSTI)

    Splitter, Derek A [ORNL; Hendricks, Terry Lee [Sandia National Laboratories (SNL); Ghandhi, Jaal B [University of Wisconsin

    2014-01-01T23:59:59.000Z

    The piston of a heavy-duty single-cylinder research engine was instrumented with 11 fast-response surface thermocouples, and a commercial wireless telemetry system was used to transmit the signals from the moving piston. The raw thermocouple data were processed using an inverse heat conduction method that included Tikhonov regularization to recover transient heat flux. By applying symmetry, the data were compiled to provide time-resolved spatial maps of the piston heat flux and surface temperature. A detailed comparison was made between conventional diesel combustion and reactivity-controlled compression ignition combustion operations at matched conditions of load, speed, boost pressure, and combustion phasing. The integrated piston heat transfer was found to be 24% lower, and the mean surface temperature was 25 C lower for reactivity-controlled compression ignition operation as compared to conventional diesel combustion, in spite of the higher peak heat release rate. Lower integrated piston heat transfer for reactivity-controlled compression ignition was found over all the operating conditions tested. The results showed that increasing speed decreased the integrated heat transfer for conventional diesel combustion and reactivity-controlled compression ignition. The effect of the start of injection timing was found to strongly influence conventional diesel combustion heat flux, but had a negligible effect on reactivity-controlled compression ignition heat flux, even in the limit of near top dead center high-reactivity fuel injection timings. These results suggest that the role of the high-reactivity fuel injection does not significantly affect the thermal environment even though it is important for controlling the ignition timing and heat release rate shape. The integrated heat transfer and the dynamic surface heat flux were found to be insensitive to changes in boost pressure for both conventional diesel combustion and reactivity-controlled compression ignition. However, for reactivity-controlled compression ignition, the mean surface temperature increased with changes in boost suggesting that equivalence ratio affects steady-state heat transfer.

  16. DistrictHeating Nuevasaladecalderasydistribucin

    E-Print Network [OSTI]

    Fraguela, Basilio B.

    DistrictHeating Nuevasaladecalderasydistribución decaloreneláreauniversitariade AZapateira Jesús, difusión. DISTRICT HEATING O CALEFACCIÓN DE BARRIO #12;MATERIALIZACIÓN INTEGRACIÓN VISUAL DE ELEMENTOS rendimiento global de la instalación. - Contabilización de pérdidas en tuberías de distribución. #12;DISTRICT

  17. HEAT TRANSFER FLUIDS

    E-Print Network [OSTI]

    Lenert, Andrej

    2012-01-01T23:59:59.000Z

    The choice of heat transfer fluids has significant effects on the performance, cost, and reliability of solar thermal systems. In this chapter, we evaluate existing heat transfer fluids such as oils and molten salts based ...

  18. CORQUENCH: A model for gas sparging-enhanced, melt-water, film-boiling heat transfer

    SciTech Connect (OSTI)

    Farmer, M.T.; Sienicki, J.J.; Spencer, B.W.

    1990-01-01T23:59:59.000Z

    In evaluation of severe-accident sequences for water-cooled nuclear reactors, molten core materials may be postulated to be released into the containment and accumulate on concrete. The heatup and decomposition of concrete is accompanied by the release of water vapor and carbon dioxide gases. Gases flowing through the melt upper surface can influence the rates of heat transfer to water overlying the melt. In particular, the gas flow through the interface can be envisioned to enhance the heat removal from the melt. A mechanistic model (CORQUENCH) has been developed to describe film-boiling heat transfer between a molten pool and an overlying coolant layer in the presence of sparging gas. The model favorably predicts the lead-Feron 11 data of Greene and Greene et al. for which the calculations indicate that area enhancement in the conduction heat transfer across the film is the predominant mechanism leading to augmentation in the heat flux as the gas velocity increases. Predictions for oxidic corium indicate a rapid increase in film-boiling heat flux as the gas velocity rises. The predominant mode of heat transfer for this case is radiation, and the increase in heat flux with gas velocity is primarily a result of interfacial area enhancement of the radiation component of the overall heat transfer coefficient. The CORQUENCH model has been incorporated into the MELTSPREAD-1 computer code{sup 6} for the analysis of transient spreading in containments.

  19. A statistical analysis of avalanching heat transport in stationary enhanced core confinement regimes

    SciTech Connect (OSTI)

    Tokunaga, S.; Jhang, Hogun; Kim, S. S. [WCI Center for Fusion Theory, National Fusion Research Institute, 52, Yeoeun-dong, Yusung-Gu, Daejon (Korea, Republic of); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, 52, Yeoeun-dong, Yusung-Gu, Daejon (Korea, Republic of); Center for Astrophysics and Space Sciences and Department of Physics, University of California San Diego, La Jolla, California 92093-0429 (United States)

    2012-09-15T23:59:59.000Z

    We present a statistical analysis of heat transport in stationary enhanced confinement regimes obtained from flux-driven gyrofluid simulations. The probability density functions of heat flux in improved confinement regimes, characterized by the Nusselt number, show significant deviation from Gaussian, with a markedly fat tail, implying the existence of heat avalanches. Two types of avalanching transport are found to be relevant to stationary states, depending on the degree of turbulence suppression. In the weakly suppressed regime, heat avalanches occur in the form of quasi-periodic (QP) heat pulses. Collisional relaxation of zonal flow is likely to be the origin of these QP heat pulses. This phenomenon is similar to transient limit cycle oscillations observed prior to edge pedestal formation in recent experiments. On the other hand, a spectral analysis of heat flux in the strongly suppressed regime shows the emergence of a 1/f (f is the frequency) band, suggesting the presence of self-organized criticality (SOC)-like episodic heat avalanches. This episodic 1/f heat avalanches have a long temporal correlation and constitute the dominant transport process in this regime.

  20. MA HEAT Loan Overview

    Broader source: Energy.gov [DOE]

    Presents information on the success of Massachusetts's HEAT loan offerings and how the financing tool is funded.

  1. Abrasion resistant heat pipe

    DOE Patents [OSTI]

    Ernst, Donald M. (Leola, PA)

    1984-10-23T23:59:59.000Z

    A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  2. Solar heat receiver

    DOE Patents [OSTI]

    Hunt, Arlon J. (Oakland, CA); Hansen, Leif J. (Berkeley, CA); Evans, David B. (Orinda, CA)

    1985-01-01T23:59:59.000Z

    A receiver for converting solar energy to heat a gas to temperatures from 700.degree.-900.degree. C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  3. Solar heat receiver

    DOE Patents [OSTI]

    Hunt, A.J.; Hansen, L.J.; Evans, D.B.

    1982-09-29T23:59:59.000Z

    A receiver is described for converting solar energy to heat a gas to temperatures from 700 to 900/sup 0/C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  4. Industrial Waste Heat Recovery

    E-Print Network [OSTI]

    Ward, M. E.; Solomon, N. G.; Tabb, E. S.

    1980-01-01T23:59:59.000Z

    INDUSTRIAL WASTE HEAT RECOVREY M. E. Ward and N. G. Solomon E. S. Tabb Solar Turbines International and Gas Research Institute San Diego, California Chicago, Illinois ABSTRACT i I One hundred fifty reports were reviewed along with interviews... tests, promising low temperature heat exchanger tube alloys and coated surfaces were identified. 1INTROUCTION of advanced technology heat recovery techniques 1_ Recovering waste heat from the flue gases of the pr~ary objective. Specific objectives...

  5. A corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, S.L.

    1987-08-10T23:59:59.000Z

    A corrosive and erosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is pumped through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium. 3 figs., 3 tabs.

  6. Acoustic Heating Peter Ulmschneider

    E-Print Network [OSTI]

    Ulmschneider, Peter

    mechanisms. 1. The acoustic heating theory Only a few years after Edlen's (1941) discovery that the solar acoustic wave radiation- · b. field acoustic wave Figure 1. Panel a: Acoustic heating in late-type stars: effective temperature TeJ f, gravity g and mixing length parameter fr. Panel b: Acoustic heating in early

  7. Heat Transfer Guest Editorial

    E-Print Network [OSTI]

    Kandlikar, Satish

    Journal of Heat Transfer Guest Editorial We are indeed delighted in bringing out this special issue was showcased in diverse areas such as traditional heat and mass transfer, lab-on-chip, sensors, biomedical applica- tions, micromixers, fuel cells, and microdevices. Selected papers in the field of heat transfer

  8. Pioneering Heat Pump Project

    Broader source: Energy.gov [DOE]

    Project objectives: To install and monitor an innovative WaterFurnace geothermal system that is technologically advanced and evolving; To generate hot water heating from a heat pump that uses non-ozone depleting refrigerant CO2. To demonstrate the energy efficiency of this system ground source heat pump system.

  9. Liquid heat capacity lasers

    DOE Patents [OSTI]

    Comaskey, Brian J. (Walnut Creek, CA); Scheibner, Karl F. (Tracy, CA); Ault, Earl R. (Livermore, CA)

    2007-05-01T23:59:59.000Z

    The heat capacity laser concept is extended to systems in which the heat capacity lasing media is a liquid. The laser active liquid is circulated from a reservoir (where the bulk of the media and hence waste heat resides) through a channel so configured for both optical pumping of the media for gain and for light amplification from the resulting gain.

  10. A surface renewal model to analyze infrared image sequences of the ocean surface for the study of air-sea heat

    E-Print Network [OSTI]

    Garbe, Christoph S.

    A surface renewal model to analyze infrared image sequences of the ocean surface for the study of air-sea heat and gas exchange C. S. Garbe Interdisciplinary Center for Scientific Computing renewal, the net heat flux, and the heat transfer velocity during nighttime. The techniques are based

  11. New configurations of a heat recovery absorption heat pump integrated with a natural gas boiler for boiler efficiency improvement

    SciTech Connect (OSTI)

    Qu, Ming [Purdue University, West Lafayette, IN; Abdelaziz, Omar [ORNL; Yin, Hongxi [Southeast University, Nanjing, China

    2014-11-01T23:59:59.000Z

    Conventional natural gas-fired boilers exhaust flue gas direct to the atmosphere at 150 200 C, which, at such temperatures, contains large amount of energy and results in relatively low thermal efficiency ranging from 70% to 80%. Although condensing boilers for recovering the heat in the flue gas have been developed over the past 40 years, their present market share is still less than 25%. The major reason for this relatively slow acceptance is the limited improvement in the thermal efficiency of condensing boilers. In the condensing boiler, the temperature of the hot water return at the range of 50 60 C, which is used to cool the flue gas, is very close to the dew point of the water vapor in the flue gas. Therefore, the latent heat, the majority of the waste heat in the flue gas, which is contained in the water vapor, cannot be recovered. This paper presents a new approach to improve boiler thermal efficiency by integrating absorption heat pumps with natural gas boilers for waste heat recovery (HRAHP). Three configurations of HRAHPs are introduced and discussed. The three configurations are modeled in detail to illustrate the significant thermal efficiency improvement they attain. Further, for conceptual proof and validation, an existing hot water-driven absorption chiller is operated as a heat pump at operating conditions similar to one of the devised configurations. An overall system performance and economic analysis are provided for decision-making and as evidence of the potential benefits. These three configurations of HRAHP provide a pathway to achieving realistic high-efficiency natural gas boilers for applications with process fluid return temperatures higher than or close to the dew point of the water vapor in the flue gas.

  12. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2750-C Segerstrom Ave., Santa Ana, CA 92704)

    1980-01-01T23:59:59.000Z

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer. The heat pump part of the system heats or cools a house or other structure through a combination of evaporation and absorption or, conversely, condensation and desorption, in a pair of containers. A set of automatic controls change the system for operation during winter and summer months and for daytime and nighttime operation to satisfactorily heat and cool a house during an entire year. The absorber chamber is subjected to solar heating during regeneration cycles and is covered by one or more layers of glass or other transparent material. Daytime home air used for heating the home is passed at appropriate flow rates between the absorber container and the first transparent cover layer in heat transfer relationship in a manner that greatly reduce eddies and resultant heat loss from the absorbant surface to ambient atmosphere.

  13. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN); Perez-Blanco, Horacio (Knoxville, TN)

    1984-01-01T23:59:59.000Z

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  14. Applied heat transfer

    SciTech Connect (OSTI)

    Ganapathy, V.

    1982-01-01T23:59:59.000Z

    Heat transfer principles are discussed with emphasis on the practical aspects of the problems. Correlations for heat transfer and pressure drop from several worldwide sources for flow inside and outside of tubes, including finned tubes are presented, along with design and performance calculations of heat exchangers economizers, air heaters, condensers, waste-heat boilers, fired heaters, superheaters, and boiler furnaces. Vibration analysis for tube bundles and heat exchangers are also discussed, as are estimating gas-mixture properties at atmospheric and elevated pressures and life-cycle costing techniques. (JMT)

  15. High-Flux Microchannel Solar Receiver

    Broader source: Energy.gov [DOE]

    This fact sheet describes a high-flux, microchannel solar receiver project awarded under the DOE's 2012 SunShot Concentrating Solar Power R&D award program. The team, led by Oregon State University, is working to demonstrate a microchannel-based solar receiver capable of absorbing high solar flux, while using a variety of liquid and gaseous working fluids. High-flux microchannel receivers have the potential to dramatically reduce the size and cost of a solar receiver by minimizing re-radiation and convective losses.

  16. Friction in Mid-latitude Bob Plant, Stephen Belcher, Bob Beare, Andy Brown

    E-Print Network [OSTI]

    Plant, Robert

    Friction in Mid-latitude Cyclones Ian Boutle Bob Plant, Stephen Belcher, Bob Beare, Andy Brown #12;Motivation · Many studies have shown the significance of friction in formation and dissipation of cyclones Dt = + × . F . Diabatic Term: · Surface heat fluxes · Latent heat fluxes Frictional Term

  17. Heat pump apparatus

    DOE Patents [OSTI]

    Nelson, Paul A. (Wheaton, IL); Horowitz, Jeffrey S. (Woodridge, IL)

    1983-01-01T23:59:59.000Z

    A heat pump apparatus including a compact arrangement of individual tubular reactors containing hydride-dehydride beds in opposite end sections, each pair of beds in each reactor being operable by sequential and coordinated treatment with a plurality of heat transfer fluids in a plurality of processing stages, and first and second valves located adjacent the reactor end sections with rotatable members having multiple ports and associated portions for separating the hydride beds at each of the end sections into groups and for simultaneously directing a plurality of heat transfer fluids to the different groups. As heat is being generated by a group of beds, others are being regenerated so that heat is continuously available for space heating. As each of the processing stages is completed for a hydride bed or group of beds, each valve member is rotated causing the heat transfer fluid for the heat processing stage to be directed to that bed or group of beds. Each of the end sections are arranged to form a closed perimeter and the valve member may be rotated repeatedly about the perimeter to provide a continuous operation. Both valves are driven by a common motor to provide a coordinated treatment of beds in the same reactors. The heat pump apparatus is particularly suitable for the utilization of thermal energy supplied by solar collectors and concentrators but may be used with any source of heat, including a source of low-grade heat.

  18. Active microchannel heat exchanger

    DOE Patents [OSTI]

    Tonkovich, Anna Lee Y. (Pasco, WA) [Pasco, WA; Roberts, Gary L. (West Richland, WA) [West Richland, WA; Call, Charles J. (Pasco, WA) [Pasco, WA; Wegeng, Robert S. (Richland, WA) [Richland, WA; Wang, Yong (Richland, WA) [Richland, WA

    2001-01-01T23:59:59.000Z

    The present invention is an active microchannel heat exchanger with an active heat source and with microchannel architecture. The microchannel heat exchanger has (a) an exothermic reaction chamber; (b) an exhaust chamber; and (c) a heat exchanger chamber in thermal contact with the exhaust chamber, wherein (d) heat from the exothermic reaction chamber is convected by an exothermic reaction exhaust through the exhaust chamber and by conduction through a containment wall to the working fluid in the heat exchanger chamber thereby raising a temperature of the working fluid. The invention is particularly useful as a liquid fuel vaporizer and/or a steam generator for fuel cell power systems, and as a heat source for sustaining endothermic chemical reactions and initiating exothermic reactions.

  19. Tetrakis-amido high flux membranes

    DOE Patents [OSTI]

    McCray, S.B.

    1989-10-24T23:59:59.000Z

    Composite RO membranes of a microporous polymeric support and a polyamide reaction product of a tetrakis-aminomethyl compound and a polyacylhalide are disclosed, said membranes exhibiting high flux and good chlorine resistance.

  20. A low cost high flux solar simulator

    E-Print Network [OSTI]

    Codd, Daniel S.

    A low cost, high flux, large area solar simulator has been designed, built and characterized for the purpose of studying optical melting and light absorption behavior of molten salts. Seven 1500 W metal halide outdoor ...

  1. Policies supporting Heat Pump Technologies

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Policies supporting Heat Pump Technologies in Canada IEA Heat Pump Workshop London, UK November 13 in the world, with an average of 16,995 kilowatt-hours per annum. #12;Canada's Context for Heat Pumps Impacts avenues: Ground source heat pumps for cold climates (heating and cooling) Reversible air source heat

  2. Radiative Heating of the ISCCP Upper Level Cloud Regimes and its Impact on the Large-scale Tropical Circulation

    SciTech Connect (OSTI)

    Li, Wei; Schumacher, Courtney; McFarlane, Sally A.

    2013-01-31T23:59:59.000Z

    Radiative heating profiles of the International Satellite Cloud Climatology Project (ISCCP) cloud regimes (or weather states) were estimated by matching ISCCP observations with radiative properties derived from cloud radar and lidar measurements from the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) sites at Manus, Papua New Guinea, and Darwin, Australia. Focus was placed on the ISCCP cloud regimes containing the majority of upper level clouds in the tropics, i.e., mesoscale convective systems (MCSs), deep cumulonimbus with cirrus, mixed shallow and deep convection, and thin cirrus. At upper levels, these regimes have average maximum cloud occurrences ranging from 30% to 55% near 12 km with variations depending on the location and cloud regime. The resulting radiative heating profiles have maxima of approximately 1 K/day near 12 km, with equal heating contributions from the longwave and shortwave components. Upper level minima occur near 15 km, with the MCS regime showing the strongest cooling of 0.2 K/day and the thin cirrus showing no cooling. The gradient of upper level heating ranges from 0.2 to 0.4 K/(day?km), with the most convectively active regimes (i.e., MCSs and deep cumulonimbus with cirrus) having the largest gradient. When the above heating profiles were applied to the 25-year ISCCP data set, the tropics-wide average profile has a radiative heating maximum of 0.45Kday-1 near 250 hPa. Column-integrated radiative heating of upper level cloud accounts for about 20% of the latent heating estimated by the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR). The ISCCP radiative heating of tropical upper level cloud only slightly modifies the response of an idealized primitive equation model forced with the tropics-wide TRMM PR latent heating, which suggests that the impact of upper level cloud is more important to large-scale tropical circulation variations because of convective feedbacks rather than direct forcing by the cloud radiative heating profiles. However, the height of the radiative heating maxima and gradient of the heating profiles are important to determine the sign and patterns of the horizontal circulation anomaly driven by radiative heating at upper levels.

  3. Optimization of Heat Exchangers

    SciTech Connect (OSTI)

    Ivan Catton

    2010-10-01T23:59:59.000Z

    The objective of this research is to develop tools to design and optimize heat exchangers (HE) and compact heat exchangers (CHE) for intermediate loop heat transport systems found in the very high temperature reator (VHTR) and other Generation IV designs by addressing heat transfer surface augmentation and conjugate modeling. To optimize heat exchanger, a fast running model must be created that will allow for multiple designs to be compared quickly. To model a heat exchanger, volume averaging theory, VAT, is used. VAT allows for the conservation of mass, momentum and energy to be solved for point by point in a 3 dimensional computer model of a heat exchanger. The end product of this project is a computer code that can predict an optimal configuration for a heat exchanger given only a few constraints (input fluids, size, cost, etc.). As VAT computer code can be used to model characteristics )pumping power, temperatures, and cost) of heat exchangers more quickly than traditional CFD or experiment, optimization of every geometric parameter simultaneously can be made. Using design of experiment, DOE and genetric algorithms, GE, to optimize the results of the computer code will improve heat exchanger disign.

  4. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F.; Moore, Paul B.

    1983-06-21T23:59:59.000Z

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  5. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F. (Shaker Heights, OH); Moore, Paul B. (Fedhaven, FL)

    1983-01-01T23:59:59.000Z

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  6. Fluidized bed heat treating system

    DOE Patents [OSTI]

    Ripley, Edward B; Pfennigwerth, Glenn L

    2014-05-06T23:59:59.000Z

    Systems for heat treating materials are presented. The systems typically involve a fluidized bed that contains granulated heat treating material. In some embodiments a fluid, such as an inert gas, is flowed through the granulated heat treating medium, which homogenizes the temperature of the heat treating medium. In some embodiments the fluid may be heated in a heating vessel and flowed into the process chamber where the fluid is then flowed through the granulated heat treating medium. In some embodiments the heat treating material may be liquid or granulated heat treating material and the heat treating material may be circulated through a heating vessel into a process chamber where the heat treating material contacts the material to be heat treated. Microwave energy may be used to provide the source of heat for heat treating systems.

  7. Summer HeatSummer Heat Heat stress solutions

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    occur (then drink a lightly salted beverage like a sports drink). The water's temperature should be cool How should gardeners avoid becoming a safety threat to themselves and others when it's hot? Start to the heat. Become a weather watcher. Set up a small weather station (with a high/low thermom eter, rain

  8. au flux diffus: Topics by E-print Network

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

    contribution of the GRB prompt and scattered emissions to the measured extragalactic gamma-ray flux. To estimate this contribution we optimistically require that the energy flux...

  9. Integration of Novel Flux Coupling Motor and Current Source Inverter...

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

    Merit Review and Peer Evaluation ape034hsu2011p.pdf More Documents & Publications Integration of Novel Flux Coupling Motor and Current Source Inverter Novel Flux Coupling...

  10. CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope...

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

    Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor Contractor ORR CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor Contractor ORR...

  11. CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope...

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

    Oak Ridge National Laboratory High Flux Isotope Reactor CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor February 2007 A section of Appendix C to DOE G...

  12. Process for heating coal-oil slurries

    DOE Patents [OSTI]

    Braunlin, W.A.; Gorski, A.; Jaehnig, L.J.; Moskal, C.J.; Naylor, J.D.; Parimi, K.; Ward, J.V.

    1984-01-03T23:59:59.000Z

    Controlling gas to slurry volume ratio to achieve a gas holdup of about 0.4 when heating a flowing coal-oil slurry and a hydrogen containing gas stream allows operation with virtually any coal to solvent ratio and permits operation with efficient heat transfer and satisfactory pressure drops. The critical minimum gas flow rate for any given coal-oil slurry will depend on numerous factors such as coal concentration, coal particle size distribution, composition of the solvent (including recycle slurries), and type of coal. Further system efficiency can be achieved by operating with multiple heating zones to provide a high heat flux when the apparent viscosity of the gas saturated slurry is highest. Operation with gas flow rates below the critical minimum results in system instability indicated by temperature excursions in the fluid and at the tube wall, by a rapid increase and then decrease in overall pressure drop with decreasing gas flow rate, and by increased temperature differences between the temperature of the bulk fluid and the tube wall. At the temperatures and pressures used in coal liquefaction preheaters the coal-oil slurry and hydrogen containing gas stream behaves essentially as a Newtonian fluid at shear rates in excess of 150 sec[sup [minus]1]. The gas to slurry volume ratio should also be controlled to assure that the flow regime does not shift from homogeneous flow to non-homogeneous flow. Stable operations have been observed with a maximum gas holdup as high as 0.72. 29 figs.

  13. Viscoelastic Models of Tidally Heated Exomoons

    E-Print Network [OSTI]

    Dobos, Vera

    2015-01-01T23:59:59.000Z

    Tidal heating of exomoons may play a key role in their habitability, since the elevated temperature can melt the ice on the body even without significant solar radiation. The possibility of life is intensely studied on Solar System moons such as Europa or Enceladus, where the surface ice layer covers tidally heated water ocean. Tidal forces may be even stronger in extrasolar systems, depending on the properties of the moon and its orbit. For studying the tidally heated surface temperature of exomoons, we used a viscoelastic model for the first time. This model is more realistic than the widely used, so-called fixed Q models, because it takes into account the temperature dependency of the tidal heat flux, and the melting of the inner material. With the use of this model we introduced the circumplanetary Tidal Temperate Zone (TTZ), that strongly depends on the orbital period of the moon, and less on its radius. We compared the results with the fixed Q model and investigated the statistical volume of the TTZ usi...

  14. Process for heating coal-oil slurries

    DOE Patents [OSTI]

    Braunlin, Walter A. (Spring, TX); Gorski, Alan (Lovington, NM); Jaehnig, Leo J. (New Orleans, LA); Moskal, Clifford J. (Oklahoma City, OK); Naylor, Joseph D. (Houston, TX); Parimi, Krishnia (Allison Park, PA); Ward, John V. (Arvada, CO)

    1984-01-03T23:59:59.000Z

    Controlling gas to slurry volume ratio to achieve a gas holdup of about 0.4 when heating a flowing coal-oil slurry and a hydrogen containing gas stream allows operation with virtually any coal to solvent ratio and permits operation with efficient heat transfer and satisfactory pressure drops. The critical minimum gas flow rate for any given coal-oil slurry will depend on numerous factors such as coal concentration, coal particle size distribution, composition of the solvent (including recycle slurries), and type of coal. Further system efficiency can be achieved by operating with multiple heating zones to provide a high heat flux when the apparent viscosity of the gas saturated slurry is highest. Operation with gas flow rates below the critical minimum results in system instability indicated by temperature excursions in the fluid and at the tube wall, by a rapid increase and then decrease in overall pressure drop with decreasing gas flow rate, and by increased temperature differences between the temperature of the bulk fluid and the tube wall. At the temperatures and pressures used in coal liquefaction preheaters the coal-oil slurry and hydrogen containing gas stream behaves essentially as a Newtonian fluid at shear rates in excess of 150 sec.sup. -1. The gas to slurry volume ratio should also be controlled to assure that the flow regime does not shift from homogeneous flow to non-homogeneous flow. Stable operations have been observed with a maximum gas holdup as high as 0.72.

  15. High-flux magnetorheology at elevated temperatures

    E-Print Network [OSTI]

    Ocalan, Murat

    Commercial applications of magnetorheological (MR) fluids often require operation at elevated temperatures as a result of surrounding environmental conditions or intense localized viscous heating. Previous experimental ...

  16. Water-heating dehumidifier

    DOE Patents [OSTI]

    Tomlinson, John J. (Knoxville, TN)

    2006-04-18T23:59:59.000Z

    A water-heating dehumidifier includes a refrigerant loop including a compressor, at least one condenser, an expansion device and an evaporator including an evaporator fan. The condenser includes a water inlet and a water outlet for flowing water therethrough or proximate thereto, or is affixed to the tank or immersed into the tank to effect water heating without flowing water. The immersed condenser design includes a self-insulated capillary tube expansion device for simplicity and high efficiency. In a water heating mode air is drawn by the evaporator fan across the evaporator to produce cooled and dehumidified air and heat taken from the air is absorbed by the refrigerant at the evaporator and is pumped to the condenser, where water is heated. When the tank of water heater is full of hot water or a humidistat set point is reached, the water-heating dehumidifier can switch to run as a dehumidifier.

  17. Heat storage duration

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1981-01-01T23:59:59.000Z

    Both the amount and duration of heat storage in massive elements of a passive building are investigated. Data taken for one full winter in the Balcomb solar home are analyzed with the aid of sub-system simulation models. Heat storage duration is tallied into one-day intervals. Heat storage location is discussed and related to overall energy flows. The results are interpreted and conclusions drawn.

  18. Simplified Numerical Description of Latent Storage Characteristics for Phase Change Wallboard

    E-Print Network [OSTI]

    Fuestel, H.E.

    2011-01-01T23:59:59.000Z

    the discharge of thermal energy storage without "dumping"thermal mass, and • utilize low-energy heating and cooling sources. Large thermal storagelow- energy cooling sources. Large thermal storage devices

  19. HEATS: Thermal Energy Storage

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    HEATS Project: The 15 projects that make up ARPA-E’s HEATS program, short for “High Energy Advanced Thermal Storage,” seek to develop revolutionary, cost-effective ways to store thermal energy. HEATS focuses on 3 specific areas: 1) developing high-temperature solar thermal energy storage capable of cost-effectively delivering electricity around the clock and thermal energy storage for nuclear power plants capable of cost-effectively meeting peak demand, 2) creating synthetic fuel efficiently from sunlight by converting sunlight into heat, and 3) using thermal energy storage to improve the driving range of electric vehicles (EVs) and also enable thermal management of internal combustion engine vehicles.

  20. Heat and mass exchanger

    DOE Patents [OSTI]

    Lowenstein, Andrew (Princeton, NJ); Sibilia, Marc J. (Princeton, NJ); Miller, Jeffrey A. (Hopewell, NJ); Tonon, Thomas (Princeton, NJ)

    2007-09-18T23:59:59.000Z

    A mass and heat exchanger includes at least one first substrate with a surface for supporting a continuous flow of a liquid thereon that either absorbs, desorbs, evaporates or condenses one or more gaseous species from or to a surrounding gas; and at least one second substrate operatively associated with the first substrate. The second substrate includes a surface for supporting the continuous flow of the liquid thereon and is adapted to carry a heat exchange fluid therethrough, wherein heat transfer occurs between the liquid and the heat exchange fluid.

  1. Heat and mass exchanger

    DOE Patents [OSTI]

    Lowenstein, Andrew (Princeton, NJ); Sibilia, Marc J. (Princeton, NJ); Miller, Jeffrey A. (Hopewell, NJ); Tonon, Thomas (Princeton, NJ)

    2011-06-28T23:59:59.000Z

    A mass and heat exchanger includes at least one first substrate with a surface for supporting a continuous flow of a liquid thereon that either absorbs, desorbs, evaporates or condenses one or more gaseous species from or to a surrounding gas; and at least one second substrate operatively associated with the first substrate. The second substrate includes a surface for supporting the continuous flow of the liquid thereon and is adapted to carry a heat exchange fluid therethrough, wherein heat transfer occurs between the liquid and the heat exchange fluid.

  2. Waste Heat Recovery

    Office of Environmental Management (EM)

    DRAFT - PRE-DECISIONAL - DRAFT 1 Waste Heat Recovery 1 Technology Assessment 2 Contents 3 1. Introduction to the TechnologySystem ......

  3. Passive solar space heating

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1980-01-01T23:59:59.000Z

    An overview of passive solar space heating is presented indicating trends in design, new developments, performance measures, analytical design aids, and monitored building results.

  4. Heat rejection system

    DOE Patents [OSTI]

    Smith, Gregory C. (Richland, WA); Tokarz, Richard D. (Richland, WA); Parry, Jr., Harvey L. (Richland, WA); Braun, Daniel J. (Richland, WA)

    1980-01-01T23:59:59.000Z

    A cooling system for rejecting waste heat consists of a cooling tower incorporating a plurality of coolant tubes provided with cooling fins and each having a plurality of cooling channels therein, means for directing a heat exchange fluid from the power plant through less than the total number of cooling channels to cool the heat exchange fluid under normal ambient temperature conditions, means for directing water through the remaining cooling channels whenever the ambient temperature rises above the temperature at which dry cooling of the heat exchange fluid is sufficient and means for cooling the water.

  5. Modeling threat assessments of water supply systems using markov latent effects methodology.

    SciTech Connect (OSTI)

    Silva, Consuelo Juanita

    2006-12-01T23:59:59.000Z

    Recent amendments to the Safe Drinking Water Act emphasize efforts toward safeguarding our nation's water supplies against attack and contamination. Specifically, the Public Health Security and Bioterrorism Preparedness and Response Act of 2002 established requirements for each community water system serving more than 3300 people to conduct an assessment of the vulnerability of its system to a terrorist attack or other intentional acts. Integral to evaluating system vulnerability is the threat assessment, which is the process by which the credibility of a threat is quantified. Unfortunately, full probabilistic assessment is generally not feasible, as there is insufficient experience and/or data to quantify the associated probabilities. For this reason, an alternative approach is proposed based on Markov Latent Effects (MLE) modeling, which provides a framework for quantifying imprecise subjective metrics through possibilistic or fuzzy mathematics. Here, an MLE model for water systems is developed and demonstrated to determine threat assessments for different scenarios identified by the assailant, asset, and means. Scenario assailants include terrorists, insiders, and vandals. Assets include a water treatment plant, water storage tank, node, pipeline, well, and a pump station. Means used in attacks include contamination (onsite chemicals, biological and chemical), explosives and vandalism. Results demonstrated highest threats are vandalism events and least likely events are those performed by a terrorist.

  6. Production flux of sea spray aerosol

    SciTech Connect (OSTI)

    de Leeuw, G.; Lewis, E.; Andreas, E. L.; Anguelova, M. D.; Fairall, C. W.; O’Dowd, C.; Schulz, M.; Schwartz, S. E.

    2011-05-07T23:59:59.000Z

    Knowledge of the size- and composition-dependent production flux of primary sea spray aerosol (SSA) particles and its dependence on environmental variables is required for modeling cloud microphysical properties and aerosol radiative influences, interpreting measurements of particulate matter in coastal areas and its relation to air quality, and evaluating rates of uptake and reactions of gases in sea spray drops. This review examines recent research pertinent to SSA production flux, which deals mainly with production of particles with r{sub 80} (equilibrium radius at 80% relative humidity) less than 1 {micro}m and as small as 0.01 {micro}m. Production of sea spray particles and its dependence on controlling factors has been investigated in laboratory studies that have examined the dependences on water temperature, salinity, and the presence of organics and in field measurements with micrometeorological techniques that use newly developed fast optical particle sizers. Extensive measurements show that water-insoluble organic matter contributes substantially to the composition of SSA particles with r{sub 80} < 0.25 {micro}m and, in locations with high biological activity, can be the dominant constituent. Order-of-magnitude variation remains in estimates of the size-dependent production flux per white area, the quantity central to formulations of the production flux based on the whitecap method. This variation indicates that the production flux may depend on quantities such as the volume flux of air bubbles to the surface that are not accounted for in current models. Variation in estimates of the whitecap fraction as a function of wind speed contributes additional, comparable uncertainty to production flux estimates.

  7. Scale/Analytical Analyses of Freezing and Convective Melting with Internal Heat Generation

    SciTech Connect (OSTI)

    Ali S. Siahpush; John Crepeau; Piyush Sabharwall

    2013-07-01T23:59:59.000Z

    Using a scale/analytical analysis approach, we model phase change (melting) for pure materials which generate constant internal heat generation for small Stefan numbers (approximately one). The analysis considers conduction in the solid phase and natural convection, driven by internal heat generation, in the liquid regime. The model is applied for a constant surface temperature boundary condition where the melting temperature is greater than the surface temperature in a cylindrical geometry. The analysis also consider constant heat flux (in a cylindrical geometry).We show the time scales in which conduction and convection heat transfer dominate.

  8. Enhanced boiling heat transfer in horizontal test bundles

    SciTech Connect (OSTI)

    Trewin, R.R.; Jensen, M.K.; Bergles, A.E.

    1994-08-01T23:59:59.000Z

    Two-phase flow boiling from bundles of horizontal tubes with smooth and enhanced surfaces has been investigated. Experiments were conducted in pure refrigerant R-113, pure R-11, and mixtures of R-11 and R-113 of approximately 25, 50, and 75% of R-113 by mass. Tests were conducted in two staggered tube bundles consisting of fifteen rows and five columns laid out in equilateral triangular arrays with pitch-to-diameter ratios of 1.17 and 1.5. The enhanced surfaces tested included a knurled surface (Wolverine`s Turbo-B) and a porous surface (Linde`s High Flux). Pool boiling tests were conducted for each surface so that reference values of the heat transfer coefficient could be obtained. Boiling heat transfer experiments in the tube bundles were conducted at pressures of 2 and 6 bar, heat flux values from 5 to 80 kW/m{sup 2}s, and qualities from 0% to 80%, Values of the heat transfer coefficients for the enhanced surfaces were significantly larger than for the smooth tubes and were comparable to the values obtained in pool boiling. It was found that the performance of the enhanced tubes could be predicted using the pool boiling results. The degradation in the smooth tube heat transfer coefficients obtained in fluid mixtures was found to depend on the difference between the molar concentration in the liquid and vapor.

  9. Economic analysis of wind-powered farmhouse and farm building heating systems. Final report

    SciTech Connect (OSTI)

    Stafford, R.W.; Greeb, F.J.; Smith, M.F.; Des Chenes, C.; Weaver, N.L.

    1981-01-01T23:59:59.000Z

    The study evaluated the break-even values of wind energy for selected farmhouses and farm buildings focusing on the effects of thermal storage on the use of WECS production and value. Farmhouse structural models include three types derived from a national survey - an older, a more modern, and a passive solar structure. The eight farm building applications that were analyzed include: poultry-layers, poultry-brooding/layers, poultry-broilers, poultry-turkeys, swine-farrowing, swine-growing/finishing, dairy, and lambing. These farm buildings represent the spectrum of animal types, heating energy use, and major contributions to national agricultural economic values. All energy analyses were based on hour-by-hour computations which allowed for growth of animals, sensible and latent heat production, and ventilation requirements. Hourly or three-hourly weather data obtained from the National Climatic Center was used for the nine chosen analysis sites, located throughout the United States and corresponding to regional agricultural production centers.

  10. IMPLEMENTING GROUND SOURCE HEAT PUMP AND GROUND LOOP HEAT EXCHANGER

    E-Print Network [OSTI]

    IMPLEMENTING GROUND SOURCE HEAT PUMP AND GROUND LOOP HEAT EXCHANGER MODELS IN THE ENERGYPLUS #12;ii IMPLEMENTING GROUND SOURCE HEAT PUMP AND GROUND LOOP HEAT EXCHANGER MODELS IN THE ENERGYPLUS............................................................... 2 1.3. Overview of the Parameter Estimation Water-to-Water Heat Pump Model ........... 5 1

  11. Heat pipes and use of heat pipes in furnace exhaust

    DOE Patents [OSTI]

    Polcyn, Adam D. (Pittsburgh, PA)

    2010-12-28T23:59:59.000Z

    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  12. First university owned district heating system using biomass heat

    E-Print Network [OSTI]

    Northern British Columbia, University of

    Highlights · First university owned district heating system using biomass heat · Capacity: 15 MMBtu Main Campus District Heating Performance · Avoided: 3500 tonnes of CO2 · Particulate: less than 10 mg District Heating Goals To displace 85% of natural gas used for core campus heating. Fuel Bunker Sawmill

  13. Comparison of ELM heat loads in snowflake and standard divertors

    SciTech Connect (OSTI)

    Rognlien, T D; Cohen, R H; Ryutov, D D; Umansky, M V

    2012-05-08T23:59:59.000Z

    An analysis is given of the impact of the tokamak divertor magnetic structure on the temporal and spatial divertor heat flux from edge localized modes (ELMs). Two configurations are studied: the standard divertor where the poloidal magnetic field (B{sub p}) varies linearly with distance (r) from the magnetic null and the snowflake where B{sub p} varies quadratrically with r. Both one and two-dimensional models are used to analyze the effect of the longer magnetic field length between the midplane and the divertor plate for the snowflake that causes a temporal dilation of the ELM divertor heat flux. A second effect discussed is the appearance of a broad region near the null point where the poloidal plasma beta can substantially exceed unity, especially for the snowflake configuration during the ELM; such a condition is likely to drive additional radial ELM transport.

  14. Microchannel heat sink assembly

    DOE Patents [OSTI]

    Bonde, W.L.; Contolini, R.J.

    1992-03-24T23:59:59.000Z

    The present invention provides a microchannel heat sink with a thermal range from cryogenic temperatures to several hundred degrees centigrade. The heat sink can be used with a variety of fluids, such as cryogenic or corrosive fluids, and can be operated at a high pressure. The heat sink comprises a microchannel layer preferably formed of silicon, and a manifold layer preferably formed of glass. The manifold layer comprises an inlet groove and outlet groove which define an inlet manifold and an outlet manifold. The inlet manifold delivers coolant to the inlet section of the microchannels, and the outlet manifold receives coolant from the outlet section of the microchannels. In one embodiment, the manifold layer comprises an inlet hole extending through the manifold layer to the inlet manifold, and an outlet hole extending through the manifold layer to the outlet manifold. Coolant is supplied to the heat sink through a conduit assembly connected to the heat sink. A resilient seal, such as a gasket or an O-ring, is disposed between the conduit and the hole in the heat sink in order to provide a watertight seal. In other embodiments, the conduit assembly may comprise a metal tube which is connected to the heat sink by a soft solder. In still other embodiments, the heat sink may comprise inlet and outlet nipples. The present invention has application in supercomputers, integrated circuits and other electronic devices, and is suitable for cooling materials to superconducting temperatures. 13 figs.

  15. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1984-01-01T23:59:59.000Z

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  16. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1984-01-01T23:59:59.000Z

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate intallation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  17. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1984-01-01T23:59:59.000Z

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to faciliate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  18. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1981-01-01T23:59:59.000Z

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  19. Couette flow regimes with heat transfer in rarefied gas

    SciTech Connect (OSTI)

    Abramov, A. A., E-mail: alabr54@mail.ru; Butkovskii, A. V., E-mail: albutkov@mail.ru [Zhukovski Central Aerohydrodynamics Institute (Russian Federation)

    2013-06-15T23:59:59.000Z

    Based on numerical solution of the Boltzmann equation by direct statistic simulation, the Couette flow with heat transfer is studied in a broad range of ratios of plate temperatures and Mach numbers of a moving plate. Flow regime classification by the form of the dependences of the energy flux and friction stress on the Knudsen number Kn is proposed. These dependences can be simultaneously monotonic and nonmonotonic and have maxima. Situations are possible in which the dependence of the energy flux transferred to a plate on Kn has a minimum, while the dependence of the friction stress is monotonic or even has a maximum. Also, regimes exist in which the dependence of the energy flux on Kn has a maximum, while the dependence of the friction stress is monotonic, and vice versa.

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

    E-Print Network [OSTI]

    Paik, Sokwon

    2006-08-16T23:59:59.000Z

    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 ...